Sample records for acaricide exposed scabies

  1. [Scabies].

    PubMed

    Hafner, C

    2009-02-01

    Scabies is an infectious disease caused by Sarcoptes scabiei var. hominis. The disease is mainly transmitted by close personal contact. The primary clinical picture is characterized by burrows at typical areas as well as severe pruritus, while secondarily a rather non-specific exanthema can be observed. The detection of mites or mite products (eggs, feces) confirms the diagnosis; dermatoscopy may facilitate the diagnosis. First choice therapy for most variants of scabies is topical permethrin. Oral administration of ivermectin is recommended for some special indications. In the following article, the current knowledge about epidemiology, biology, immunology, clinical appearance, diagnostic procedures and therapy of scabies is reviewed. PMID:19189068

  2. Scabies.

    PubMed

    Hicks, Maria I; Elston, Dirk M

    2009-01-01

    Scabies is an ectoparasite caused by the mite Sarcoptes scabiei var hominis, an obligate human parasite. There are about 300 million cases of scabies in the world each year. Common predisposing factors are overcrowding, immigration, poor hygiene, poor nutritional status, homelessness, dementia, and sexual contact. Direct skin-to-skin contact between 15 and 20 minutes is needed to transfer the mites from one person to another. The diagnosis suspected with a clinical history of itch, worse at night, affecting other family members, clinical distribution, and appearance. Definite diagnosis relies on microscopic identification of the mites, eggs, or fecal pellets with 10% potassium hydroxide, ink enhancement, tetracycline fluorescence tests, or mineral oil; other methods include: epiluminescence light microscopy and S. scabiei DNA. The most commonly used treatment modalities are permethrin and ivermectin. Persistence of symptoms for 2-6 weeks after successful treatment is common. Most recurrences are because of reinfection from untreated contacts. PMID:19580575

  3. Microarray analysis of gene expression in acaricide-exposed Rhipcephalus (Boophilus) microplus larvae.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Acaricide-inducible differential gene expression was studied in larvae of Rhipicephalus (Boophilus) microplus using a microarray-based approach. The acaricides used were: coumaphos, permethrin, ivermectin, and amitraz. The microarrays contained over 13,000 probes, having been derived from a previous...

  4. Scabies Diagnosis

    MedlinePLUS

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  5. Morphological alterations of epidermis of rabbits infested by R. sanguineus ticks and exposed to Selamectin (active principle of Pfizer Revolution(®) acaricide): a confocal microscopy study.

    PubMed

    Bozzatto, Vlamir; Oliveira, Patrícia Rosa de; Bechara, Gervásio Henrique; Camargo-Mathias, Maria Izabel

    2014-04-01

    The present study analyzed, by means of confocal laser scanning microscopy, the epidermis of rabbits infested by the brown dog tick Rhipicephalus sanguineus and exposed to concentrations of 50%, 80% and 100% of a selamectin-based commercial acaricide (Pfizer's Revolution(®)). The results demonstrated that rabbits exposed to concentrations of 80% and 100% of the Revolution acaricide, which contains 12% selamectin, showed thinning of epithelial tissue of the epidermis with associated cellular disorganization. Individuals exposed to a 50% concentration showed lower epidermal tissue disorganization when compared to those exposed to the higher doses of the acaricide (80% and 100%). Whereas selamectin, when used in higher concentrations (80% and 100% Revolution(®)) can alter the morphology of the epidermis, at lower concentrations (50%), even though still able to eliminate ectoparasites, it causes less toxicity damage to the host. Selamectin can be considered a dose-dependent toxic agent, since higher concentrations increase the morphological changes in the epidermis of the host rabbits. PMID:24369880

  6. Immune-related gene expression in nurse honey bees (Apis mellifera) exposed to synthetic acaricides.

    PubMed

    Garrido, Paula Melisa; Antúnez, Karina; Martín, Mariana; Porrini, Martín Pablo; Zunino, Pablo; Eguaras, Martín Javier

    2013-01-01

    The mite Varroa destructor is an ectoparasite affecting honey bees worldwide. Synthetic acaricides have been among the principal tools available to beekeepers for its control, although several studies have shown its negative effects on honey bee physiology. Recent research suggests that those molecules strongly impact on immune signaling cascades and cellular immunity. In the present work, LC(50) in six-day-old bees were determined for the following acaricides: tau-fluvalinate, flumethrin, amitraz and coumaphos. According to this obtained value, a group of individuals was treated with each acaricide and then processed for qPCR analysis. Transcript levels for genes encoding antimicrobial peptides and immune-related proteins were assessed. Flumethrin increased the expression of hymenoptaecin when comparing treated and control bees. Significant differences were recorded between coumaphos and flumethrin treatments, while the first one reduced the expression of hymenoptaecin and abaecin, the last one up-regulated their expressions. No significant statistically changes were recorded in the expression levels of vitellogenin, lysozyme or glucose dehydrogenase among bees treated with acaricides and control bees. This work constitutes the first report, under laboratory conditions, about induction of immune related genes in response to synthetic miticides. PMID:23147024

  7. Susceptibility of Varroa destructor (Acari: Varroidae) to synthetic acaricides in Uruguay: Varroa mites’ potential to develop acaricide resistance

    Microsoft Academic Search

    Matías Daniel Maggi; Sergio Roberto Ruffinengo; Yamandú Mendoza; Pilar Ojeda; Gustavo Ramallo; Iganazio Floris; Martín Javier Eguaras

    2011-01-01

    The purpose of this study was to estimate the acaricide susceptibility of Varroa destructor populations from Uruguay, which had never been exposed to synthetic acaricides. It was also to determine whether acaricide\\u000a resistance to coumaphos occurred in apiaries in which acaricide rotation had been applied. Bioassays with acaricides against\\u000a mite populations that had never been exposed to synthetic acaricides were

  8. Scabies: Treatment

    MedlinePLUS

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  9. Cowdria Ruminantium Antibodies in Acaricide-Treated and Untreated Cattle Exposed to Amblyomma Variegatum Ticks in The Gambia

    Microsoft Academic Search

    R. C. Mattioli; M. Bah; R. Reibel; F. Jongejan

    2000-01-01

    An indirect enzyme-linked immunosorbent assay (ELISA), based on the major antigenic protein 1 fragment B (MAP1-B) of Cowdria ruminantium, was used to assess seroprevalence in cattle in The Gambia. Two groups of 20 N'Dama and 20 Gobra zebu cattle were monitored for 12 months with flumethrin treatment and for another 10 months without acaricidal treatment. Two groups of 20 N'Dama

  10. The occurrence of autophagic cell death in the tegument of rabbits pre-infested with Rhipicephalus sanguineus and exposed to selamectin (active principle of acaricide Pfizer Revolution®).

    PubMed

    Bozzatto, Vlamir; Oliveira, Patrícia Rosa De; Furquim, Karim Christina Scopinho; Camargo-Mathias, Maria Izabel

    2013-11-01

    Ticks of Rhipicephalus sanguineus species have great medical and veterinary importance for being a vector of various diseases. In an attempt to minimize their action on the host, people have resorted to chemical control by using various acaricides, such as selamectin. Although previous studies have demonstrated its toxic action in domestic animals, no studies focused on the detection of cell death when exposed to selamectin. For this reason, the technique for detecting autophagic cell death was used in order to demonstrate the responses of rabbits' skin tissues pre-infested with R. sanguineus and exposed to different concentrations of selamectin. The obtained results when exposed to 100 and 80% concentrations of selamectin showed a strong mark of acid phosphatase on the cells of the connective tissue of the dermis and hair follicles, whereas the ones exposed to the 50% concentration had a weak mark on the cells of the connective tissue of the dermis and moderate staining in hair follicles. It became clear that, when used at high concentrations (100 and 80%), selamectin is capable to induce a large scale occurrence of the autophagic cell death process. On the other hand, the concentration of 50% causes minor morphophysiological changes in the skin of rabbit hosts when evaluated the cell death process. Therefore, the data confirms that selamectin is a powerful dose-dependent toxic agent causes increased activity of the enzyme acid phosphatase. PMID:23983162

  11. Cowdria ruminantium antibodies in acaricide-treated and untreated cattle exposed to Amblyomma variegatum ticks in The Gambia.

    PubMed

    Mattioli, R C; Bah, M; Reibel, R; Jongejan, F

    2000-01-01

    An indirect enzyme-linked immunosorbent assay (ELISA), based on the major antigenic protein I fragment B (MAPI-B) of Cowdria ruminantium, was used to assess seroprevalence in cattle in The Gambia. Two groups of 20 N'Dama and 20 Gobra zebu cattle were monitored for 12 months with flumethrin treatment and for another 10 months without acaricidal treatment. Two groups of 20 N'Dama and 20 Gobra cattle served as untreated controls. During the period of acaricidal treatment, the cumulative proportions of positive serum samples were 25.6 +/- 5.6% (+/- confidence interval) and 34.7 +/- 6.8% in treated N'Dama and Gobra cattle respectively; the proportion of positive sera in untreated cattle was 52.2 +/- 6.9% in N'Damas and 61.4 +/- 7.3% in Gobras. Within breed, difference in antibody prevalence between treated and untreated cattle was significant (P < 0.001) but between breed differences were not significant. In the 10 months following suspension of acaricide application, there was an increase of proportion of positive serum samples in previously treated N'Dama and Gobra cattle. In both previously treated and untreated animals the peak of positive seroreactions occurred during and subsequent to the period of activity of Amblyomma variegatum adults. Cumulative seroprevalences in previously treated N'Dama and Gobra cattle were 32.6 +/- 6.9% and 44.7 +/- 8.5%, respectively; in untreated animals seroprevalence was 38.6 +/- 7.2% in N'Dama and 65.3 +/- 8.4% in Gobra cattle. Throughout the study period, within the N'Dama breed, the seropositive rate in previously treated cattle did not differ from that in untreated animals. Conversely, within the Gobra breed, the number of positive seroreactions was higher (P < 0.002) in untreated animals than in previously treated cattle. These results provide a support for designing A. variegatum and heartwater control strategies, if necessary, in The Gambia in relation to cattle breeds. PMID:11354623

  12. Treatment of scabies infestations.

    PubMed

    Mumcuoglu, K Y; Gilead, L

    2008-09-01

    Scabies is an intensely pruritic disorder induced by an immune allergic response to infestation of the skin by the mite Sarcoptes scabiei. The biology of the mite, the clinical aspects and diagnosis of scabies infestations as well as the treatment of choice with 5% permethrin dermal cream and the use of scabicides based on other chemical substances are reviewed. PMID:18814689

  13. Scabies: Prevention and Control

    MedlinePLUS

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  14. Scabies: Disease Symptoms

    MedlinePLUS

    ... message, please visit this page: About CDC.gov . Parasites - Scabies Parasites Home Share Compartir Disease When a person is ... reaction) to the proteins and feces of the parasite. Severe itching (pruritus), especially at night, is the ...

  15. Travelers' Health: Scabies

    MedlinePLUS

    ... gov . Home Destinations Travel Notices Find a Clinic Yellow Fever Vaccinations Clinics FAQ Disease Directory Information Centers For Travelers Common Travel Health Topics Adopting a Child from Another Country Adventure ... Contents Chapter 3 (78) Scabies more Tables ...

  16. Management of scabies.

    PubMed

    Monsel, Gentiane; Chosidow, Olivier

    2012-03-01

    Scabies is a common contagious parasitic dermatosis. Transmission of the mite Sarcoptes scabiei var hominis generally occurs by skin-to-skin contact, but with crusted scabies it may also occur through fomites, such as infected clothing or bedding. Diagnosis is usually clinical. A 2010 updated Cochrane review concluded that management of scabies is based on topical scabicides, mainly 5% permethrin. However, oral ivermectin, although not licensed in many countries, may be useful, particularly for patients who cannot tolerate or comply with topical therapy and in institutional scabies epidemics. Patients should also receive detailed information about the infestation to limit further spreading. Cases resulting from close physical or sexual contact, even without symptoms, should be systematically treated. Hygienic measures should be taken after treatment is completed. Patients should be followed to confirm cure, including resolution of itching, which may take up to 4 weeks or longer. PMID:22446818

  17. Psoriasis or crusted scabies.

    PubMed

    Goyal, N N; Wong, G A

    2008-03-01

    We describe a case of a 67-year-old woman with a 1-year history of nail thickening and a non-itchy erythematous scaly eruption on the fingertips. She was diagnosed with psoriasis and started on methotrexate after having had no response to topical calcipotriol. The diagnosis was reviewed after it was revealed by another consultant that the patient's husband had been attending dermatology clinics for several years with chronic pruritus, which had been repeatedly thought to be due to scabies. Our patient was found to have crusted scabies after a positive skin scraping showed numerous mites. She was treated with topical permethrin, keratolytics and oral ivermectin. We also review the literature on crusted scabies and its management, with recommendations. PMID:18257840

  18. [Scabies in 2012].

    PubMed

    Gaspard, Lionel; Laffitte, Emmanuel; Michaud, Mélanie; Eicher, Nicole; Lacour, Odile; Toutous-Trellu, Laurence

    2012-04-01

    Scabies is a parasitic infection known all over the world and particularly in a low socioeconomic context and in institutions. The transmission is mainly direct from skin-to-skin. An increase of cases has been observed in Geneva since October 2011. To confirm the diagnosis, a precise clinical and microbiological examination is required and highly recommended before starting a treatment. Scabies management includes treatment of the patient and his close contacts with antiparasitic drugs as well as thorough cleaning of clothes and bed linen. When available, oral ivermectine is the treatment of choice, topical permethrine is prescribed when ivermectine cannot be used or in association with it in severe presentations. In Switzerland, ivermectine is not readily available, it is expensive and not reimbursed by insurances. PMID:22545492

  19. [Scabies as an occupational disease].

    PubMed

    Lukács, J; Schliemann, S; Elsner, P

    2015-03-01

    Scabies is an infectious skin disease caused by the human itch mite (Sarcoptes scabiei var. hominis). It is mainly transmitted by direct skin-to-skin contact. The spread of scabies can cause major difficulties in healthcare institutions, particularly in residential homes for the elderly. The disease is characterized by intense nocturnal itching, erythematous papules arranged in a linear order, and scratching resulting in excoriations. The diagnosis is confirmed by identification of the mite or by finding one or more mite tunnels in the skin. An individually occurring case does not need to be reported. If two or more cases occur in the same institution, the company physician and the appropriate public health department are to be informed in Germany. In case of a suspected scabies infection in medical personnel due to exposure in their work setting, medical notification to the statutory occupational accidents' insurance (Nr. 3101) is to be issued in accordance with § 202, Volume VII of the German Social Code. First line treatment is topical therapy with 5?% permethrin. If scabies control is required in an institution, systemic treatment with ivermectin may be considered. In the case of a scabies outbreak, all patients, contact persons, and staff must be treated simultaneously. PMID:25676574

  20. Histopathology of the tegument of rabbits infested by Rhipicephalus sanguineus (ACARI: IXODIDAE) ticks and exposed to selamectin (active principle of acaricide Revolution, Pfizer).

    PubMed

    Bozzatto, Vlamir; de Oliveira, Patrícia Rosa; Camargo-Mathias, Maria Izabel

    2013-07-01

    Ticks are hematophagous ectoparasites which can transmit several diseases to the host during their feeding process. When ticks mechanically damage the tissue, they eventually induce inflammatory responses on the skin spot where they are fixed. One of the alternatives to control these ectoparasites is the use of chemical substances like selamectin-the active principle of Pfizer's antiparasitic Revolution-a macrocyclic lactone capable of doing neurotoxic damage to the tick and eventually eliminating infestation in dogs and cats. The purpose of this study was to analyze, using histological and histochemical techniques, the occurrence of morphophysiological alterations in the skin of the host rabbits exposed to selamectin and infested with Rhipicephalus sanguineus (Acari: Ixodidae). Histologically, the exposed and infested rabbits showed a partial and/or total decrease in the stratum corneum and the epithelium decreased in the number of cell layers, consequently reducing the stratification (thinning) and quite pronounced formations of sub-epidermal edemas with consequent disorganization of collagen fibers in the dermal layer's connective tissue. Histochemical tests showed strong periodic acid-Schiff-positive reaction in the hair follicle and some regions of the dermis, besides resynthesis of collagen fibers detected by Mallory's trichrome technique. The obtained results showed that selamectin acts like a toxicant agent when in contact with the skin of the rabbit infested with ticks, inducing morphophysiological alterations in the acute inflammatory process in the animal's tegument. Selamectin is a chemical substance which has a dose-dependent action since higher concentrations cause greater morphophysiological damage in the skin of rabbits. PMID:23613180

  1. Diagnosis, prevention, and treatment of scabies.

    PubMed

    Shimose, Luis; Munoz-Price, L Silvia

    2013-10-01

    Scabies remains a public health problem, especially in developing countries, with a worldwide incidence of approximately 300 million cases each year. Prolonged skin-to-skin contact is necessary to allow the transmission of the causative mite, Sarcoptes scabiei. Classic scabies presents with burrows, erythematous papules, and generalized pruritus. Clinical variants include nodular scabies and crusted scabies, also called Norwegian scabies. The diagnosis is based mainly on history and physical examination, but definitive diagnosis depends on direct visualization of the mites under microscopy. Alternative diagnostic methods include the burrow ink test, video-dermatoscopy, newly serologic tests like PCR/ELISA, and specific IgE directed toward major mite components. Treatment of scabies consists of either topical permethrin or oral ivermectin, although the optimal regimen is still unclear. PMID:23904181

  2. Ectoparasitic sexually transmitted diseases: Scabies and pediculosis

    Microsoft Academic Search

    Edith Orion; Hagit Matz; Ronni Wolf

    2004-01-01

    Scabies and pediculosis are diagnosed on an almost daily basis in many dermatology offices. Whether the patient seeks medical attention because of the often unbearable itch of scabies or because of the fear of lice infestations, the physician should be on the lookout for these ectoparasitic infestations. Secondary bacterial infection, resistance to medication, and the risk of spread of the

  3. [Bullous scabies responding to ivermectin therapy].

    PubMed

    Galvany Rossell, L; Salleras Redonnet, M; Umbert Millet, P

    2010-01-01

    Bullous scabies is a rare disease that is usually diagnosed in elderly patients. The clinical, histological, and immunological findings are identical to bullous pemphigoid. In a review of the literature, we found reports of 24 cases. We present a new case of bullous scabies in a 72-year-old man. The lesions responded to treatment with oral ivermectin. PMID:20109396

  4. Scabies and bedbugs in hospital outbreaks.

    PubMed

    Sfeir, Maroun; Munoz-Price, L Silvia

    2014-08-01

    Scabies and bedbugs are two emerging ectoparasitic infections reported in crowded areas, including hospitals. Skin involvement is the main presenting initial manifestation for both infections, and the diagnosis is yet challenging for both. Topical permethrin is considered the first-line therapy for scabies except for crusted scabies which is mainly treated with oral ivermectin. To the contrary, treatment of bedbugs is mainly symptomatic. Avoiding close contact, early diagnosis and treatment of infected persons as well as decontamination of the involved environment play an essential role in controlling outbreaks in healthcare settings. PMID:24897948

  5. Acaricidal activity of extracts from Ligularia virgaurea against the Sarcoptes scabiei mite in vitro

    PubMed Central

    LUO, BIAO; LIAO, FEI; HU, YANCHUN; LIU, XI; HE, YAJUN; WU, LEI; TAN, HUI; LUO, LIJUAN; ZHOU, YANCHENG; MO, QUAN; DENG, JUNLIANG; WEI, YAHUI

    2015-01-01

    The aim of the present study was to investigate the acaricidal activity of Ligularia virgaurea. An extract was prepared by refluxing with ethanol and steam distillation, and its toxic effect was tested in vitro against Sarcoptes scabiei. The data from the toxicity tests were analyzed using a complementary log-log (CLL) model. The ethanol extract exhibited strong acaricidal activity against these mites; at a concentration of 2 g/ml it killed all S. scabiei within 2 h and at 1 g/ml it killed all S. scabiei within 6 h. Similarly, 2, 1, 0.5 and 0.25 g/ml concentrations of the extract had strong toxicity against S. scabiei, with median lethal time (LT50) values of 0.716, 1.741, 2.968 and 4.838 h, respectively. The median lethal concentration (LC50) values were 1.388, 0.624, 0.310 and 0.213 g/ml for Scabies mite in 1, 2, 4 and 6 h, respectively. The results indicate that the L. virgaurea extract has strong acaricidal activity and may be exploited as a novel treatment for the effective control of acariasis in animals. PMID:26170943

  6. Atypical scabies presenting as annular patches.

    PubMed

    Hossain, Delwar

    2014-01-01

    Scabies is a common parasitic disease that can be recognized by the development of itchy lesions and a predilection for certain places on the body. It may infrequently present with patchy lesions. We report a patient with well-defined annular patches. Histopathology showed an egg of the scabies mite in the epidermis. Treatment with permethrin cream resulted in complete resolution of her disease. PMID:22967356

  7. Scabies

    MedlinePLUS

    ... I have a terrible, itchy rash around my anal area. ACK, help! I’m having itching and peeling around my vagina? Should I be worried? Tweets by @CYWH The Center for Young Women’s Health (CYWH) is a collaboration between the Division of Adolescent and Young Adult Medicine and the Division of ...

  8. Past, Present, and Future of Chemical Acaricides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There have been many different acaricides and acaricide formulations used throughout the history of tick control. Originally, various mixtures of crude oil, lard, sulfur, and kerosene were used for dipping livestock. This was followed by Beaumont crude oil. Arsenical dips were introduced in 1911 and...

  9. Crusted scabies and multiple dosages of ivermectin.

    PubMed

    Ortega-Loayza, Alex G; McCall, Calvin O; Nunley, Julia R

    2013-05-01

    We present the case of a bone marrow transplant patient who was diagnosed with crusted scabies but did not respond to the usual approach with topical permethrin and ivermectin. The Centers for Disease Control and Prevention were contacted and suggested a 7-dose regimen of ivermectin. The patient started to improve remarkably after the third dose, and the skin eruption was resolved after 7 doses. This case supports the use of a more prolonged course of oral ivermectin for crusted scabies in those who fail the conventional approach. PMID:23652958

  10. Itch and scratch: scabies and pediculosis

    Microsoft Academic Search

    Edith Orion; Batsheva Marcos; Batya Davidovici; Ronni Wolf

    2006-01-01

    Scabies and lice infestations are almost an everyday diagnosis in the dermatology clinics. Along with the unbearable itch, resistance to medication, secondary infection, and the high risk for spreading the parasite to their close contacts, the patients have also to battle with many myths, prejudice, and shames connected to those infestations.

  11. Scabies, pediculosis, bedbugs, and stinkbugs: uncommon presentations

    Microsoft Academic Search

    Tania Ferreira Cestari; Beatriz Farias Martignago

    2005-01-01

    Parasitic agents determine some of the most common skin disorders. Although well known, they could present different manifestations or be modified by individual or external factors that make their diagnosis or treatment difficult. This review will discuss some of the most prevalent parasitic infections, scabies, and pediculosis and also mention reactions determined by contact with certain insects that, although rarely

  12. 9 CFR 73.8 - Cattle infected or exposed during transit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... SCABIES IN CATTLE § 73.8 Cattle infected or exposed during transit. (a) Healthy cattle from unquarantined State exposed en route. Should healthy cattle in transit from a State not quarantined by the Secretary of Agriculture...

  13. Streptomyces scabies 87-22 Possesses a Functional Tomatinase

    Microsoft Academic Search

    Ryan F. Seipke; Rosemary Loria

    2008-01-01

    The actinomycete Streptomyces scabies 87-22 is the causal agent of common scab, an economically important disease of potato and taproot crops. Sequencing of the S. scabies 87-22 genome revealed the presence of a gene with high homology to the gene encoding the -tomatine-detoxifying enzyme tomatinase found in fungal tomato pathogens. The tomA gene from S. scabies 87-22 was cotranscribed with

  14. An elderly long-term care resident with crusted scabies.

    PubMed

    Sandre, Matthew; Ralevski, Filip; Rau, Neil

    2015-01-01

    Crusted scabies is a highly contagious form of scabies. Altered immune response, nutritional deficiencies and modified host response are all risk factors for crusted scabies. The authors report a case involving a patient found to have a chronic maculopapular, erythematous rash with large hyperkeratotic, white and grey plaques on the soles of both feet. An ultimate diagnosis of crusted scabies was reached after a delay in diagnosis suspected to be caused by the similarity in appearance to more common skin conditions such as psoriasis. After topical permethrin was unsuccessful, intermittent dosing of oral ivermectin resulted in a rapid reduction in cutaneous plaques. PMID:25798153

  15. An elderly long-term care resident with crusted scabies

    PubMed Central

    Sandre, Matthew; Ralevski, Filip; Rau, Neil

    2015-01-01

    Crusted scabies is a highly contagious form of scabies. Altered immune response, nutritional deficiencies and modified host response are all risk factors for crusted scabies. The authors report a case involving a patient found to have a chronic maculopapular, erythematous rash with large hyperkeratotic, white and grey plaques on the soles of both feet. An ultimate diagnosis of crusted scabies was reached after a delay in diagnosis suspected to be caused by the similarity in appearance to more common skin conditions such as psoriasis. After topical permethrin was unsuccessful, intermittent dosing of oral ivermectin resulted in a rapid reduction in cutaneous plaques. PMID:25798153

  16. Scabies: more than just an irritation

    PubMed Central

    McCarthy, J; Kemp, D; Walton, S; Currie, B

    2004-01-01

    Human scabies, caused by skin infestation with the arthropod mite, Sarcoptes scabiei, typically results in a papular, intensely pruritic eruption involving the interdigital spaces, and flexure creases. Recent research has led to a reassessment of the morbidity attributable to this parasite in endemic communities, particularly resulting from secondary skin sepsis and postinfective complications including glomerulonephritis. This has led to studies of the benefits of community based control programmes, and to concerns regarding the emergence of drug resistance when such strategies are employed. The renewed research interest into the biology of this infection has resulted in the application of molecular tools. This has established that canine and human scabies populations are genetically distinct, a finding with major implications for the formulation of public health control policies. Further research is needed to increase understanding of drug resistance, and to identify new drug targets and potential vaccine candidates. PMID:15254301

  17. Factors associated with pediculosis pubis and scabies

    Microsoft Academic Search

    G Hart

    1992-01-01

    OBJECTIVE--To ascertain factors associated with genital pediculosis and scabies infestations among attenders at an STD clinic. DESIGN--Cross sectional assessment of potential risk factors by multiple logistic regression. SETTING--A central city sexually transmitted diseases (STD) clinic in Adelaide, South Australia. SUBJECTS--All men and women patients attending from 1988 to 1991. RESULTS--Pediculosis pubis was diagnosed in 205 of 12,170 (1.7%) men and

  18. May/June 1999 Acaricide Residues Ebelift-Barrel Handler

    E-print Network

    Ferrara, Katherine W.

    Kills Imported Fire Ant Internet Apitherapy Course Acaricide Residues Beekeepers have been putting acaricides in their hives for Varroa mite control for over a decade. Researchers in Switzerland conducted that residues of acaricides used for Varroa control have been found in beeswax. For closely controlled studies

  19. 'Wake sign': an important clue for the diagnosis of scabies.

    PubMed

    Yoshizumi, J; Harada, T

    2009-08-01

    Japan is currently experiencing many outbreaks of scabies, occurring mainly in long-term care facilities. Scabies burrows, the only pathognomonic lesion for scabies, often occur on the creases of the palms, and are followed by a pattern of scale reminiscent of the 'wake' left on the surface of water by a moving bird or a ship (wake sign).(1-4) The wake sign is useful because (i) it is specific for scabies, (ii) it is sufficiently large to be found by the naked eye and (iii) it points towards the location of the mite and its products. Examination of patients' palms to look for this sign is a simple and efficient way to make a diagnosis of scabies throughout the course of an infestation. PMID:19077100

  20. Crusted scabies in remote Australia, a new way forward: lessons and outcomes from the East Arnhem Scabies Control Program.

    PubMed

    Lokuge, Buddhi; Kopczynski, Alex; Woltmann, Angela; Alvoen, Faye; Connors, Christine; Guyula, Terrence; Mulholland, Eddie; Cran, Samantha; Foster, Tim; Lokuge, Kamalini; Burke, Tanya; Prince, Sam

    2014-06-16

    Crusted scabies is a highly infectious, debilitating and disfiguring disease, and remote Aboriginal communities of northern Australia have the highest reported rates of the condition in the world. We draw on monitoring data of the East Arnhem Scabies Control Program to discuss outcomes and lessons learnt through managing the condition in remote communities. Using active case finding, we identified seven patients with crusted scabies in three communities and found most had not presented to health services despite active disease. We compared presentations and hospitalisations for a cumulative total of 99 months during a novel preventive program with 99 months immediately before the program for the seven cases and seven sentinel household contacts. Our preventive long-term case management approach was associated with a significant 44% reduction in episodes of recurrent crusted scabies (from 36 to 20; P = 0.025) in the seven cases, and a non-significant 80% reduction in days spent in hospital (from 173 to 35; P = 0.09). It was also associated with a significant 75% reduction in scabies-related presentations (from 28 to 7; P = 0.017) for the seven sentinel household contacts. We recommend active surveillance and wider adoption of this preventive case management approach, with ongoing evaluation to refine protocols and improve efficiency. Contacts of children presenting with recurrent scabies should be examined to exclude crusted scabies. In households where crusted scabies is present, a diagnosis of parental neglect due to recurrent scabies and weight loss in children should be made with extreme caution. Improved coordination of care by health services, and research and development of new therapies including immunotherapies for crusted scabies, must be a priority. PMID:24938345

  1. Intense nocturnal itching should raise suspicion of scabies.

    PubMed

    Tidman, Alice S M; Tidman, Michael J

    2013-05-01

    Scabies is caused by infestation with a parasitic mite Sarcoptes scabiei var hominis. The itch and rash appear to be largely the result of a delayed (type IV) allergic reaction to the mite, its eggs and excreta. Scabies is spread by a mite transferring to the skin surface of an unaffected person, usually by skin to skin contact with an infested person, but occasionally via contaminated bed linen, clothes or towels. In crusted scabies, mites are also dispersed within shed scales, enabling the condition to be contracted from contaminated surfaces. Patients with classical scabies usually present with an itchy non-specific rash. Often, the history alone can be 0032-6518 virtually diagnostic. An intense itch, affecting all body regions except the head, typically worse at night, appearing to be out of proportion to the physical evidence, with a close contact also itching, should prompt serious consideration of scabies. The generalised hypersensitivity rash consists of erythematous macules and papules with excoriation. Close inspection will reveal burrows usually up to 1 cm in length. The pathognomic sign of scabies is the presence of burrows. The crusted variant of scabies may not be itchy. It is characterised by areas of dry, scaly, hyperkeratotic and crusted skin, particularly on the extremities. Referral to secondary care should be considered in the following cases: diagnostic doubt; patient under two months of age; lack of response to two ourses of different insecticides; crusted scabies; or history suggests a isk of sexually transmitted infection. Outbreaks of scabies in institutions should be referred to the local health protection services. PMID:23808128

  2. Norwegian scabies in a renal transplant patient.

    PubMed

    Sampathkumar, K; Mahaldar, A R; Ramakrishnan, M; Prabahar, S

    2010-04-01

    A variety of skin infections are encountered in postrenal transplant setting. Though bacterial and fungal infections are more common, surprises are in store for us sometimes. We describe a patient who underwent renal transplant two years ago, presenting with a painless, mildly pruritic expanding skin rash over abdomen. Histological examination of the skin biopsy showed that stratum corneum had multiple burrows containing larvae and eggs of Sarcoptes scabiei. The patient was treated with ivermectin 12 mg weekly once for 2 doses along with topical 5% permethrin and permethrin soap bath. There was remarkable improvement in the skin lesions with complete resolution in two weeks. Norwegian or crusted scabies is caused by massive infestation with Sarcoptes scabiei var. hominis. It can be rarely encountered in the post-transplant setting, which underscores the importance of early diagnosis and treatment before secondary bacterial infection sets in. PMID:20835323

  3. Serial analysis of gene expression in the southern cattle tick following acaricide treament of larvae from organophosphate resistant and susceptible strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organophosphate resistant and susceptible tick larvae from laboratory strains of the southern cattle tick, Rhipicephalus (Boophilus) microplus were exposed to low doses of the organophosphate (OP) acaricide, coumaphos. Serial analysis of gene expression (SAGE) was used to analyze differential gene e...

  4. The preparation of neem oil microemulsion (Azadirachta indica) and the comparison of acaricidal time between neem oil microemulsion and other formulations in vitro.

    PubMed

    Xu, Jiao; Fan, Qiao-Jia; Yin, Zhong-Qiong; Li, Xu-Ting; Du, Yong-Hua; Jia, Ren-Yong; Wang, Kai-Yu; Lv, Cheng; Ye, Gang; Geng, Yi; Su, Gang; Zhao, Ling; Hu, Ting-Xiu; Shi, Fei; Zhang, Li; Wu, Chang-Long; Tao, Cui; Zhang, Ya-Xue; Shi, Dong-Xia

    2010-05-11

    The preparation of neem oil microemulsion and its acaricidal activity in vitro was developed in this study. In these systems, the mixture of Tween-80 and the sodium dodecyl benzene sulfonate (SDBS) (4:1, by weight) was used as compound surfactant; the mixture of compound surfactant and hexyl alcohol (4:1, by weight) was used as emulsifier system; the mixture of neem oil, emulsifier system and water (1:3.5:5.5, by weight) was used as neem oil microemulsion. All the mixtures were stired in 800 rpm for 15 min at 40 degrees C. The acaricidal activity was measured by the speed of kill. The whole lethal time value of 10% neem oil microemulsion was 192.50 min against Sarcoptes scabiei var. cuniculi larvae in vitro. The median lethal time value was 81.7463 min with the toxicity regression equations of Y=-6.0269+3.1514X. These results demonstrated that neem oil microemulsion was effective against Sarcoptes scabie var. cuniculi larvae in vitro. PMID:20304561

  5. [Involvement of fingernails in scabies in an infant].

    PubMed

    Sokolova, T V; Sizov, I E

    1989-01-01

    An infant of 10 months, suffering from scabies, has developed multiple involvements of the nail plates on the hands and feet, with detachment of some of them. A diagnostic error has promoted the dissemination of the process. The patient has been etiologically cured by a 10% water/soap suspension of benzyl-benzoate. PMID:2728613

  6. The epidemiology of head lice and scabies in the UK.

    PubMed Central

    Downs, A. M.; Harvey, I.; Kennedy, C. T.

    1999-01-01

    Anecdotal evidence suggests that the prevalence of both scabies and head lice is increasing and also that both conditions are becoming refractory to pesticide treatment. Using information obtained from the Office of National Statistics, Royal College of General Practitioners Weekly Returns Service, Department of Health, local surveys of school children from Bristol and drug sales of insecticides, we have confirmed that there has been a rise in the prevalence of both conditions. We have shown that scabies is significantly more prevalent in urbanized areas (P < 0.00001), north of the country (P < 0.000001), in children and women (P < 0.000001) and commoner in the winter compared to the summer. Scabies was also shown to have a cyclical rise in incidence roughly every 20 years. Head lice were shown to be significantly more prevalent in children and mothers (P < 0.000001) though both conditions were seen in all age groups. Head lice were also less common during the summer. Host behaviour patterns, asymptomatic carriage, drug resistance and tourism from countries or districts with a higher incidence may be important factors in the currently high prevalence of both scabies and head lice. PMID:10459652

  7. Streptomyces scabies 87-22 possesses a functional tomatinase.

    PubMed

    Seipke, Ryan F; Loria, Rosemary

    2008-12-01

    The actinomycete Streptomyces scabies 87-22 is the causal agent of common scab, an economically important disease of potato and taproot crops. Sequencing of the S. scabies 87-22 genome revealed the presence of a gene with high homology to the gene encoding the alpha-tomatine-detoxifying enzyme tomatinase found in fungal tomato pathogens. The tomA gene from S. scabies 87-22 was cotranscribed with a putative family 1 glycosyl hydrolase gene, and purified TomA protein was active only on alpha-tomatine and not potato glycoalkaloids or xylans. Tomatinase-null mutants were more sensitive to alpha-tomatine than the wild-type strain in a disk diffusion assay. Interestingly, tomatine affected only aerial mycelium and not vegetative mycelium, suggesting that the target(s) of alpha-tomatine is not present during vegetative growth. Severities of disease for tomato seedlings affected by S. scabies 87-22 wild-type and DeltatomA1 strains were indistinguishable, suggesting that tomatinase is not important in pathogenicity on tomato plants. However, conservation of tomA on a pathogenicity island in S. acidiscabies and S. turgidiscabies suggests a role in plant-microbe interaction. PMID:18835993

  8. Treatment of scabies: Comparison of permethrin 5% versus ivermectin.

    PubMed

    Goldust, Mohamad; Rezaee, Elham; Hemayat, Sevil

    2012-06-01

    Scabies is an ectoparasitic, highly contagious skin disease caused by a mite called Sarcoptes scabiei. The insecticides ivermectin and permethrin are commonly used for treatment of scabies. This study aimed at comparing the efficacy of oral ivermectin with topical permethrin in treating scabies. Two hundred and forty-two patients with scabies attending the dermatology outpatient department of Sina Hospital, Tabriz University of Medical Sciences were admitted. Patients were divided into two groups randomly. The first group and their family contacts received 5% permethrin cream and the other received oral ivermectin. Treatment was evaluated at intervals of 2 and 4 weeks. A single dose of ivermectin provided a cure rate of 85.9% at a 2-week interval, which increased to 100% after crossing over to the permethrin group at a 4-week interval. Twice application of permethrin with a 1-week interval was effective in 92.5% of patients, which increased to 94.2% after crossing over to the ivermectin group at a 4-week interval. Permethrin-treated patients recovered earlier. Twice application of permethrin with a 1-week interval is superior to a single dose of ivermectin. The temporal dissociation in clinical response suggests that ivermectin may not be effective against all the stages in the life cycle of the parasite. PMID:22385121

  9. Structural Mechanisms of Inactivation in Scabies Mite Serine Protease Paralogues

    SciTech Connect

    Fischer, Katja; Langendorf, Christopher G.; Irving, James A.; Reynolds, Simone; Willis, Charlene; Beckham, Simone; Law, Ruby H.P.; Yang, Sundy; Bashtannyk-Puhalovich, Tanya A.; McGowan, Sheena; Whisstock, James C.; Pike, Robert N.; Kemp, David J.; Buckle, Ashley M.; (Monash); (Queensland Inst. of Med. Rsrch.)

    2009-08-07

    The scabies mite (Sarcoptes scabiei) is a parasite responsible for major morbidity in disadvantaged communities and immuno-compromised patients worldwide. In addition to the physical discomfort caused by the disease, scabies infestations facilitate infection by Streptococcal species via skin lesions, resulting in a high prevalence of rheumatic fever/heart disease in affected communities. The scabies mite produces 33 proteins that are closely related to those in the dust mite group 3 allergen and belong to the S1-like protease family (chymotrypsin-like). However, all but one of these molecules contain mutations in the conserved active-site catalytic triad that are predicted to render them catalytically inactive. These molecules are thus termed scabies mite inactivated protease paralogues (SMIPPs). The precise function of SMIPPs is unclear; however, it has been suggested that these proteins might function by binding and protecting target substrates from cleavage by host immune proteases, thus preventing the host from mounting an effective immune challenge. In order to begin to understand the structural basis for SMIPP function, we solved the crystal structures of SMIPP-S-I1 and SMIPP-S-D1 at 1.85 {angstrom} and 2.0 {angstrom} resolution, respectively. Both structures adopt the characteristic serine protease fold, albeit with large structural variations over much of the molecule. In both structures, mutations in the catalytic triad together with occlusion of the S1 subsite by a conserved Tyr200 residue is predicted to block substrate ingress. Accordingly, we show that both proteases lack catalytic function. Attempts to restore function (via site-directed mutagenesis of catalytic residues as well as Tyr200) were unsuccessful. Taken together, these data suggest that SMIPPs have lost the ability to bind substrates in a classical 'canonical' fashion, and instead have evolved alternative functions in the lifecycle of the scabies mite.

  10. Pheromone\\/acaricide mixtures in the control of the tick Amblyomma hebraeum : Effects of acaricides on attraction and attachment

    Microsoft Academic Search

    R. A. I. Norval; C. E. Yunker; I. M. Duncan; T. Peter

    1991-01-01

    Unfed adults and nymphs of the bont tickAmblyomma hebraeum Koch are attracted to hosts on which fed males, emitting an aggregation-attachment pheromone (AAP), are attached. Pheromone\\/acaricide mixtures have the potential to selectively attract and kill these ticks. We have investigated the effects of three acaricides, amitraz (an amidine), flumethrin (a synthetic pyrethroid) and chlorfenvinphos (an organophosphate), combined with AAP, on

  11. Eucalyptus globulus (camphor oil) against the zoonotic scabies, Sarcoptes scabiei.

    PubMed

    Morsy, Tosson A; Rahem, Mohammad A Abdel; el-Sharkawy, Eman M A; Shatat, Mostafa A

    2003-04-01

    In Egypt, Scarcoptes scabiei is the most prevalence mites of medical importance infesting man. This is true in overcrowded and poorly hygienic areas. Many effective acaridical regimens are available, but being compounds used as insecticides. With the success of camphor oil in treated human demodicidosis, it was applied for treating human scabies. Camphor oil with or without glycerol dilutions gave complete cure, with concentrations (100%, 75% and 50%) within five to ten days. PMID:12739800

  12. Elastosis Perforans Serpiginosa in Association with Scabies Mite

    PubMed Central

    Frederickson, Julie; Griffith, Jack; Shitabata, Paul; Horowitz, David

    2013-01-01

    Elastosis perforans serpiginosa is a form of perforating dermatoses, which has a characteristic clinical presentation of grouped keratotic papules coalescing into serpiginous or annular configurations. The majority of elastosis perforans serpiginosa cases are idiopathic; however, various etiologies have been postulated for the pathogenesis of this syndrome. The authors present a unique case of elastosis perforans serpiginosa that developed focally secondary to a scabies mite. PMID:24155992

  13. Skin disorders, including pyoderma, scabies, and tinea infections.

    PubMed

    Andrews, Ross M; McCarthy, James; Carapetis, Jonathan R; Currie, Bart J

    2009-12-01

    Pyoderma, scabies, and tinea are common childhood skin disorders too often considered to be merely of nuisance value. More than 111 million children are believed to have pyoderma, with many also co-infected with scabies, tinea, or both. These skin disorders cannot be differentiated by ethnicity or socioeconomic status but, in high-prevalence areas, poverty and overcrowded living conditions are important underlying social determinants. Each is transmitted primarily through direct skin-to-skin contact. For many Indigenous children, these skin conditions are part of everyday life. Although rarely directly resulting in hospitalization or death, there is a high and largely unmet demand for effective management at the primary health-care level, particularly for pyoderma and scabies. Despite particularly high prevalence in some settings, treatment is not sought for many children, and when sought, the clinical benefit from such consultations is variable. The lack of standard, evidence-based recommendations is of much concern. The current evidence base for clinical diagnosis and treatment of these common childhood skin disorders is highlighted. PMID:19962029

  14. Treatment of scabies, permethrin 5% cream vs. crotamiton 10% cream.

    PubMed

    Pourhasan, Abolfazl; Goldust, Mohamad; Rezaee, Elham

    2013-01-01

    Scabies is one of the three most common skin disorders in children, along with tinea and pyoderma. The treatment of choice is still controversial. The aim of this study is to compare the efficacy of permethrin 5% cream vs. crotamiton 10% cream in the treatment of scabies. In total, 350 patients with scabies were enrolled, and randomized into two groups. The first group received permethrin 5% cream on two occasions with a one-week interval, while the second group received topical crotamiton 10% cream and were told to apply this twice daily for five consecutive days. The treatment was evaluated at intervals of 2 and 4 weeks, and the treatment was repeated if treatment failure was found at the 2-week follow-up. Two applications of permethrin 5 % cream provided a cure rate of 70% at the 2-week follow-up, which increased to 85% at the 4-week follow-up after repeating the treatment. Treatment with single applications of crotamiton 10% cream was effective in 45% of patients at the 2-week follow-up, which increased to 65% at the 4-week follow-up after this treatment was repeated. Two applications of permethrin 5% cream was as effective as single applications of crotamiton 10% cream at the 2-week follow-up. After repeating the treatment, permethrin 5 % cream was superior to crotamiton 10% cream at the 4-week follow up. PMID:24881286

  15. BIOLOGICAL CONTROL Compatibility of Beauveria bassiana with Acaricides

    Microsoft Academic Search

    RENATO C. DE OLIVEIRA; PEDRO M. O. J. NEVES

    The in vitro compatibility of the entomopathogenic fungus Beauveria bassiana (Bals.) Vuil. with 12 acaricide formulations was evaluated. The active ingredients Clorfenapyr, Fenpyroximate, Amitraz, Acrinathrin, Hexythiazox, Abamectin, Pyridine, Dimethoate, Pyridaphethion, Fenbutatin Oxide, Azocyclotin and Cyhexatin were tested in three different concentrations (mean concentration - MC, half MC and twice the MC). The formulations tested affected conidial germination, vegetative growth and

  16. Effect of owner-controlled acaricidal treatment on tick infestation and immune response to tick-borne pathogens in naturally infested dogs from Eastern Austria

    PubMed Central

    2013-01-01

    Background Tick-borne infections resulting from regular tick infestation in dogs are a common veterinary health problem all over the world. The application of repellent and acaricidal agents to prevent transmission of pathogens is a major protection strategy and has been proven to be highly effective in several trials under laboratory and natural conditions in dogs. Despite such promising results, many dog owners still report tick infestation in their dogs although acaricidal agents are used. Information about the current infection status and changes of the infection status regarding tick-borne diseases (TBD) in dogs treated by the owner’s controlled acaricide application is lacking. Methods In this study 30 dogs were each treated with permethrin, fipronil + S-methoprene, or served as untreated controls. Application of the acaricide was performed by the owner who decided when and how often to use the spot on preparation. Over a period of 11 months, dogs were clinically examined and sampled for antibody responses against Babesia canis, Anaplasma phagocytophilum, Borrelia burgdorferi s. l., and TBE virus before the study started, 6 months later and at the end of the investigation period. Results The permethrin acaricide was applied on average 3.40 times within the examination period, whereas the fipronil + S-methoprene medication was applied 3.03 times. Approximately 2/3 of all dogs, independent of the group, had a positive immune response to one or more pathogens. Three dogs developed clinical symptoms of canine babesiosis, all other dogs remained healthy. Individual number of ticks per dog or number of infections per dog did not correlate with the application rate, and the number of ticks per dog did not influence the number of infections per dog. As owners did not apply the acaricides regularly no influence on the number of infections could be documented although the number of ticks was clearly reduced by the application of the spot-on drugs. Conclusions Clinical disease in dogs exposed to tick-borne pathogens is rare, although a humoral immune response reflecting infection is common. More educational training for dog owners is necessary to make the application of acaricides effective regarding the prevention of tick-borne diseases. PMID:23497548

  17. Dissecting the complete lipoprotein biogenesis pathway in Streptomyces scabies.

    PubMed

    Widdick, David A; Hicks, Matthew G; Thompson, Benjamin J; Tschumi, Andreas; Chandra, Govind; Sutcliffe, Iain C; Brülle, Juliane K; Sander, Peter; Palmer, Tracy; Hutchings, Matthew I

    2011-06-01

    Following translocation, bacterial lipoproteins are lipidated by lipoprotein diacylglycerol transferase (Lgt) and cleaved of their signal peptides by lipoprotein signal peptidase (Lsp). In Gram-negative bacteria and mycobacteria, lipoproteins are further lipidated by lipoprotein N-acyl transferase (Lnt), to give triacylated lipoproteins. Streptomyces are unusual amongst Gram-positive bacteria because they export large numbers of lipoproteins via the twin arginine protein transport (Tat) pathway. Furthermore, some Streptomyces species encode two Lgt homologues and all Streptomyces species encode two homologues of Lnt. Here we characterize lipoprotein biogenesis in the plant pathogen Streptomyces scabies and report that lgt and lsp mutants are defective in growth and development while only moderately affected in virulence. Lipoproteins are lost from the membrane in an S. scabies lgt mutant but restored by expression of Streptomyces coelicolor lgt1 or lgt2 confirming that both encode functional Lgt enzymes. Furthermore, lipoproteins are N-acylated in Streptomyces with efficient N-acylation dependent on Lnt1 and Lnt2. However, deletion of lnt1 and lnt2 has no effect on growth, development or virulence. We thus present a detailed study of lipoprotein biogenesis in Streptomyces, the first study of Lnt function in a monoderm bacterium and the first study of bacterial lipoproteins as virulence factors in a plant pathogen. PMID:21477129

  18. Two-spotted spider mite in Cyprus: ineffective acaricides, causes and considerations

    Microsoft Academic Search

    M. C. Stavrinides; M. Hadjistylli

    2009-01-01

    Growers of greenhouse roses in Cyprus have recently reported failures of several acaricides against two-spotted spider mite\\u000a (Tetranychus urticae Koch). To verify the cause of these failures we evaluated the effectiveness of seven acaricides against two rose and two\\u000a cucumber spider mite populations in the laboratory. The acaricides included in our study represented the most important mode\\u000a of action groups

  19. Problems in Diagnosing Scabies, a Global Disease in Human and Animal Populations

    PubMed Central

    Walton, Shelley F.; Currie, Bart J.

    2007-01-01

    Scabies is a worldwide disease and a major public health problem in many developing countries, related primarily to poverty and overcrowding. In remote Aboriginal communities in northern Australia, prevalences of up to 50% among children have been described, despite the availability of effective chemotherapy. Sarcoptic mange is also an important veterinary disease engendering significant morbidity and mortality in wild, domestic, and farmed animals. Scabies is caused by the ectoparasitic mite Sarcoptes scabiei burrowing into the host epidermis. Clinical symptoms include intensely itchy lesions that often are a precursor to secondary bacterial pyoderma, septicemia, and, in humans, poststreptococcal glomerulonephritis. Although diagnosed scabies cases can be successfully treated, the rash of the primary infestation takes 4 to 6 weeks to develop, and thus, transmission to others often occurs prior to therapy. In humans, the symptoms of scabies infestations can mimic other dermatological skin diseases, and traditional tests to diagnose scabies are less than 50% accurate. To aid early identification of disease and thus treatment, a simple, cheap, sensitive, and specific test for routine diagnosis of active scabies is essential. Recent developments leading to the expression and purification of S. scabiei recombinant antigens have identified a number of molecules with diagnostic potential, and current studies include the investigation and assessment of the accuracy of these recombinant proteins in identifying antibodies in individuals with active scabies and in differentiating those with past exposure. Early identification of disease will enable selective treatment of those affected, reduce transmission and the requirement for mass treatment, limit the potential for escalating mite resistance, and provide another means of controlling scabies in populations in areas of endemicity. PMID:17428886

  20. The efficacy of topical and oral ivermectin in the treatment of human scabies.

    PubMed

    Panahi, Yunes; Poursaleh, Zohreh; Goldust, Mohamad

    2015-01-01

    Scabies is an itchy skin condition caused by the microscopic mite Sarcoptes scabei. The itching is caused by an allergic reaction to the mites. The treatment of choice is still controversial. It is commonly treated with topical insecticides. The aim of this study was to assess the efficacy of topical and oral ivermectin in the treatment of human scabies. We searched electronic databases (Cochrane Occupational Safety and Health Review Group Specialised Register, CENTRAL (The Cochrane Library), MEDLINE (Ovid), Pubmed, EMBASE, LILACS, CINAHL, Open Grey and WHO ICTRP) up to September 2014. Randomized controlled trials (RCTs) or cluster RCTs which compared the efficacy of ivermectin with other medications in the treatment of scabies. Interventions could be compared to each other, or to placebo or to no treatment. The author intended to extract dichotomous data (developed infection or did not develop infection) for the effects of interventions. We intended to report any adverse outcomes similarly. It has been sated that ivermectin was as effective as permethrin in the treatment of scabies. In comparison to other medications such as lindane, benzyl benzoate, crotamiton and malathion, ivermectin was more effective in the treatment of scabies. Ivermectin is an effective and cost-comparable alternative to topical agents in the treatment of scabies infection. PMID:25911032

  1. Species-Specific Detoxification Metabolism of Fenpyroximate, a Potent Acaricide

    Microsoft Academic Search

    Kazuhiko Motoba; Hideo Nishizawa; Takashi Suzuki; Hiroshi Hamaguchi; Matazaemon Uchida; Shunji Funayama

    2000-01-01

    The mode of selective toxicity of fenpyroximate (tert-butyl (E)-?-(1,3-dimethyl-5-phenoxypyrazol-4-ylmethyleneamino-oxy)-p-toluate), a potent acaricide, was studied with respect to its detoxification metabolism. Among its metabolites examined, only ester hydrolyzed metabolites completely lost the inhibitory activity toward NADH–ubiquinone oxidoreductase, which suggested that ester hydrolysis was the key step in detoxification. After a single oral administration of fenpyroximate to rats, two labile intermediates (metabolites

  2. Norwegian scabies in a malnourished young adult: a case report.

    PubMed

    Subramaniam, Girija; Kaliaperumal, Karthikeyan; Duraipandian, Jeyakumari; Rengasamy, Gopal

    2010-05-01

    A 19-year-old male was admitted to the medical ward with complaints of fever and swelling of the ankle and wrist joints of about two weeks duration. The patient developed hyperkeratotic lesions of the skin over the hands, elbow and back about three weeks after admission. Antistreptolysin O, rheumatoid factor, and Widal tests as well as Chickungunya, brucella, HIV and antinuclear antibodies were negative. Culture of blood sample and pus aspirate from the ankle and chest yielded a pure growth of Staphylococcus epidermidis. Potassium hydroxide (KOH) mount of the scrapings from crusted skin lesions showed plenty of adult mites, eggs and faecal pellets of Sarcoptes scabiei. A diagnosis of crusted scabies with secondary bacterial infection was made and the patient was treated successfully with oral ivermectin, topical permethrin and vancomycin. PMID:20539068

  3. Geographic variation of susceptibility to acaricides in two spider mite species, Panonychus osmanthi and P. citri (Acari: Tetranychidae) in Japan

    Microsoft Academic Search

    Tetsuo Gotoh; Yasuki Kitashima; Ishizue Adachi

    2004-01-01

    The susceptibility of two Panonychus mite species to eight acaricides was examined. Many populations of P. osmanthi Ehara and Gotoh collected from Osmanthus plants and P. citri (McGregor) collected from either holly\\/yew or citrus were resistant to each of four acaricides registered before 1990, whereas almost all populations were susceptible to each of four new acaricides released on the market

  4. Possible risk factors on Queensland dairy farms for acaricide resistance in cattle tick ( Boophilus microplus)

    Microsoft Academic Search

    N. N. Jonsson; D. G. Mayer; P. E. Green

    2000-01-01

    A case control study was carried out within a cross-sectional survey designed to investigate the management by Queensland dairy farmers of the cattle tick Boophilus microplus. Although 199 farmers were surveyed, data on acaricide resistance were only obtained from 66 farms. Multiple models were used to predict the probability of acaricide resistance associated with 30 putative risk factors. The region

  5. Effect of acaricides on the activity of a Boophilus microplus glutathione S-transferase.

    PubMed

    da Silva Vaz, Itabajara; Torino Lermen, Tiago; Michelon, André; Sanchez Ferreira, Carlos Alexandre; Joaquim de Freitas, Daniela Reis; Termignoni, Carlos; Masuda, Aoi

    2004-01-30

    In the present study, we report the effect of several acaricides on the enzyme activity of a Boophilus microplus recombinant glutathione S-transferase (rGST). GST was expressed in Escherichia coli and was purified with glutathione (GSH) affinity column chromatography. The kinetic constants were determined by reacting GST with the substrates 1-chloro-2,4-dinitrobenzene (CDNB) and glutathione. We report the effect of several acaricides on the enzyme activity of rGST. Some acaricides (ethion, amitraz, chlorpyrifos, DDT, cypermethrin, diazinon, ivermectin, deltamethrin and flumethrin) inhibited rGST. Contrarily, coumaphos had an activating effect. Although the accurate mechanisms of the B. microplus resistance to acaricides remain elusive, this work helps in understanding how acaricides can interact with GST. PMID:14746982

  6. Acute toxic effects of fenpyroximate acaricide on Guppy (Poecilia reticulata Peters, 1859).

    PubMed

    Do?an, Nesli; Yaz?c?, Zehra; ?i?man, Turgay; A?kin, Hakan

    2013-09-01

    Fenpyroximate (FP), an acaricide, is widely used in the prevention of acarids (mites) in fruit plant gardens. In this study, the acute toxic effects of different concentrations of FP were investigated using adult guppy (Poecilia reticulata Peters, 1859). Guppy adults were exposed to a range of FP concentrations (25, 50, 75, 100, 125, and 150 µg/L) during 48 h. Static method, which is one of the acute toxicity experiments, has been used in this study. According to probit analysis, the 48-h median lethal concentration (LC50) value of FP at 26°C was found to be 72.821 µg/L. Sublethal exposures were predetermined based on 48-h LC50 value. Guppies were exposed to low concentrations (15, 25, and 50 µg/L) of FP for 48 h. Signs of paralysis and behavior deformations were monitored every 12 h in a number of live and dead adults. Low concentrations of FP were also responsible for erratic swimming, loss of equilibrium, and being lethargic. Liver histology revealed several pathological damages including congestion, picnotic nucleus, sinusoidal dilatation, increase in melanomacrophagic centers, and endothelial degeneration. Finally, the toxicity test results provided 48-h LC50 value for FP, and low concentrations of FP can be highly detrimental to guppy adults with clear evidence of behavioral and histologic effects. PMID:22508399

  7. Scabies: a review of diagnosis and management based on mite biology.

    PubMed

    Golant, Alexandra K; Levitt, Jacob O

    2012-01-01

    Scabies is a contagious parasitic dermatitis that is a significant cause of morbidity, especially outside of the United States. Scabies is diagnosed most often by correlating clinical suspicion with the identification of a burrow. Although scabies should be on the differential for any patient who presents with a pruritic dermatosis, clinicians must consider a wide range of diagnostic possibilities. This approach will help make scabies simultaneously less over- and underdiagnosed by clinicians in the community. Atypical or otherwise complex presentations may necessitate the use of more definitive diagnostic modalities, such as microscopic examination of KOH prepared skin scrapings, high-resolution digital photography, dermoscopy, or biopsy. Scabies therapy involves making the correct diagnosis, recognizing the correct clinical context to guide treatment of contacts and fomites, choosing the most effective medication, understanding how to use the agent properly, and following a rational basis for when to use and reuse that agent. Although the development of new therapeutic agents is always welcome, tried and true treatments are still effective today. Permethrin is the gold standard therapy, with malathion being an excellent topical alternative. Ivermectin is an effective oral alternative that is especially useful in crusted scabies, patients who are bed ridden, and in institutional outbreaks. Despite the availability of effective therapeutics, treatment failures still occur, mostly secondary to application error (ie, failure to treat the face and scalp or close contacts, failure to reapply medication) or failure to decontaminate fomites. Because increasing resistance to scabies treatments may be on the horizon, we propose that standard of care for scabies treatment should involve routine treatment of the scalp and face and re-treating patients at day 4 on the basis of the scabies life cycle to ensure more efficient mite eradication. Practitioners should attempt to treat all close contacts simultaneously with the source patient. To eradicate mites, all fomites should be placed in a dryer for 10 minutes on a high setting, furniture and carpets vacuumed, and nonlaunderables isolated for a minimum of 2 days, or, for those who wish to be rigorous, 3 weeks. PMID:22210934

  8. Parasitological and clinical studies on human scabies in Cairo.

    PubMed

    Sarwat, M A; el Okbi, L M; el Sayed, M M; el Okbi, S M; el Deeb, H K

    1993-12-01

    This study is a parasitological and clinical study on human scabies. This study was carried out on 100 patients attending the Dermatology Outpatient Clinic at Ain Shams University Hospitals, including 54 males and 46 females. All patients were subjected to detailed history taking, complete dermatological examination including Skin Scraping Test and Burrow Ink Test. Younger patients attended the dermatology clinic earlier than older patients, who usually delayed their visits until complications occurred. Scratching, erythematous papules and secondary infected lesions were the commonest lesions. The hands, wrist and external genitalia were the most frequently affected sites while the feet, ankles, knees and back were the least affected. Burrows could only be detected in 40% of patients. The most frequent sites were the web spaces, external genitalia, and finger sides. Burrow Ink Test was positive among 85% of patients with burrows while mites could be identified by Skin Scraping Test in 55% of patients. The most frequent clinical manifestations in the parasitologically positive patients were itching, burrows, and papules, and the most frequent sites were the web spaces, and the finger sides. Multiple sites affection was the characteristic feature among the preschool age children who represented 14% of cases. PMID:8308357

  9. Clinical and parasitological study on scabies in Sirte, Libya.

    PubMed

    Fathy, Fouad M; El-Kasah, Fathi; El-Ahwal, Abdulla M

    2010-12-01

    The present work aimed to determine the risk factors, clinical and parasitological skin lesion features and effective drug regimens. Study was carried out on 200 patients referred to dermatology outpatient clinics in Sirte-Libya. Each was subjected to detailed questionnaire, dermatological skin examination, parasitological skin scraping test (SST), burrow ink test (BIT), drug administration and follow up. Results revealed that females 59%, children 37.5% and military personnel 18% of immigrant families were particularly prone to scabies infestation. Effective risk factors included overcrowding, bed sharing, low hygienic and education levels. Commonest skin lesions included erythematous papules 93%, excoriated papules 77.5%, burrows 66%, pustulation 31%, vesicles 21.5 and nodules 3%. Predilection lesion sites were hand 86%, wrist 82%, abdomen 56%, male external genitalia 64.5% and female breast 28%. Specific SST was positive in 67.3% of cases, particularly sensitive in early cases with short itching duration. BIT was positive in 62%. Topical permethrin proved more effective than precipitated sulpher with cure rates of of 100% and 85.3% in 21% and 75% of cases, respectively. Ivermectin was 100% effective in 4% of cases. PMID:21268539

  10. Possible risk factors on Queensland dairy farms for acaricide resistance in cattle tick (Boophilus microplus).

    PubMed

    Jonsson, N N; Mayer, D G; Green, P E

    2000-02-29

    A case control study was carried out within a cross-sectional survey designed to investigate the management by Queensland dairy farmers of the cattle tick Boophilus microplus. Although 199 farmers were surveyed, data on acaricide resistance were only obtained from 66 farms. Multiple models were used to predict the probability of acaricide resistance associated with 30 putative risk factors. The region of the state in which the farm was located and the frequency of acaricide application were consistently associated with acaricide resistance. The risk of resistance to all synthetic pyrethroids (Parkhurst strain) was highest in Central Queensland and increased when more than five applications of acaricide were made in the previous year, when spray races were used and when buffalo fly treatments with a synthetic pyrethroid were applied frequently. The probability of resistance to amitraz (Ulam strain) was highest in Central Queensland, increased when more than five applications of acaricide were made in the previous year, and decreased on farms when a hand-spray apparatus was used to apply acaricides to cattle. The probability of resistance to flumethrin (Lamington strain) was highest in the Wide Bay-Burnett region. PMID:10681025

  11. Prospective Study in a Porcine Model of Sarcoptes scabiei Indicates the Association of Th2 and Th17 Pathways with the Clinical Severity of Scabies

    PubMed Central

    Mounsey, Kate E.; Murray, Hugh C.; Bielefeldt-Ohmann, Helle; Pasay, Cielo; Holt, Deborah C.; Currie, Bart J.; Walton, Shelley F.; McCarthy, James S.

    2015-01-01

    Background Understanding of scabies immunopathology has been hampered by the inability to undertake longitudinal studies in humans. Pigs are a useful animal model for scabies, and show clinical and immunologic changes similar to those in humans. Crusted scabies can be readily established in pigs by treatment with the glucocorticoid dexamethasone (Dex). Methodology/ Principal Findings Prospective study of 24 pigs in four groups: a) Scabies+/Dex+, b) Scabies+/Dex-, c) Scabies-/Dex+ and d) Scabies-/Dex-. Clinical symptoms were monitored. Histological profiling and transcriptional analysis of skin biopsies was undertaken to compare changes in cell infiltrates and representative cytokines. A range of clinical responses to Sarcoptes scabiei were observed in Dex treated and non-immunosuppressed pigs. An association was confirmed between disease severity and transcription of the Th2 cytokines IL-4 and IL-13, and up-regulation of the Th17 cytokines IL-17 and IL-23 in pigs with crusted scabies. Immunohistochemistry revealed marked infiltration of lymphocytes and mast cells, and strong staining for IL-17. Conclusions/ Significance While an allergic Th2 type response to scabies has been previously described, these results suggest that IL-17 related pathways may also contribute to immunopathology of crusted scabies. This may lead to new strategies to protect vulnerable subjects from contracting recurrent crusted scabies. PMID:25730203

  12. Dermoscopy of Norwegian scabies in a patient with acquired immunodeficiency syndrome.

    PubMed

    Towersey, Loan; Cunha, Marina X da; Feldman, Cecilia A; Castro, Carlos Gustavo C de; Berger, Timothy G

    2010-01-01

    The authors report here on the case of a female patient with Norwegian (crusted) scabies and acquired immunodeficiency syndrome whose compliance with antiretroviral therapy was poor. Definitive diagnosis was confirmed by direct microscopic examination, which revealed numerous Sarcoptes scabei. Dermoscopy showed pathognomonic scabetic burrows and brownish structures in the shape of a hand-glider with a millipede-like appearance. The latter constitutes a diagnostic feature in the pathology of Norwegian scabies that has not yet been described. The patient responded well to oral ivermectin and topical vaseline with sulphur at a proportion of 10%. There was a simultaneous improvement in dermoscopic parameters. PMID:20520938

  13. Scabies presenting as solitary mastocytoma-like eruption in an infant.

    PubMed

    Salces, Inés García; Alfaro, Jorge; Sáenz DE Santamaría, Maria Carmen; Sanchez, Milagros

    2009-01-01

    We report a case in which the initial clinical finding was a solitary cutaneous nodule on the wrist of a young infant which urticated when rubbed, and was diagnosed as a solitary mastocytoma. Two months later, she had the onset of a new vesiculo-pustular eruption on the palms and soles, consistent with scabies infestation and treatment with topical permethrin 5% cream resulted in resolution of the entire eruption, including the primary nodule. While scabies has been reported to mimick a variety of conditions including urticaria pigmentosa, to our knowledge no previous cases masquerading as solitary mastocytoma have been reported. PMID:19689539

  14. Effect of acaricides on the activity of a Boophilus microplus glutathione S-transferase

    Microsoft Academic Search

    Itabajara da Silva Vaz; Tiago Torino Lermen; André Michelon; Carlos Alexandre Sanchez Ferreira; Daniela Reis Joaquim de Freitas; Carlos Termignoni; Aoi Masuda

    2004-01-01

    In the present study, we report the effect of several acaricides on the enzyme activity of a Boophilus microplus recombinant glutathione S-transferase (rGST). GST was expressed in Escherichia coli and was purified with glutathione (GSH) affinity column chromatography. The kinetic constants were determined by reacting GST with the substrates 1-chloro-2,4-dinitrobenzene (CDNB) and glutathione. We report the effect of several acaricides

  15. Susceptibility of female populations of Panonychus ulmi (Koch) (Acari: Tetranychidae) to some acaricides in apple orchards

    Microsoft Academic Search

    Nabi Alper Kumral; Bahattin Kovanci

    2007-01-01

    The levels of susceptibility of adult female European red mite, Panonychus ulmi (Koch) populations collected from apple orchards in Bursa region of Turkey, to acaricides, dicofol, bromopropylate and fenpyroximate\\u000a belong to two different groups and an acaricide–insecticide, amitraz, were determined by a petri leaf disk-Potter spray tower\\u000a method. When compared with the susceptible population, resistance ratios, as indicated by LC50

  16. Topically applied myco-acaricides for the control of cattle ticks: overcoming the challenges

    Microsoft Academic Search

    Perry Polar; Dave Moore; Moses T. K. Kairo; Adash Ramsubhag

    2008-01-01

    In the absence of commercially viable and environmentally friendly options, the management of cattle ticks is heavily dependent\\u000a on the use of chemical acaricides. Due to recent advances in production, formulation and application technology, commercial\\u000a fungus-based biological pesticides (myco-insecticides, myco-acaricides) are becoming increasingly popular for the control\\u000a of plant pests; however, they have not been used against animal ectoparasites. The

  17. Thaxtomin A production and virulence are controlled by several bld gene global regulators in Streptomyces scabies.

    PubMed

    Bignell, Dawn R D; Francis, Isolde M; Fyans, Joanna K; Loria, Rosemary

    2014-08-01

    Streptomyces scabies is the main causative agent of common scab disease, which leads to significant annual losses to potato growers worldwide. The main virulence factor produced by S. scabies is a phytotoxic secondary metabolite called thaxtomin A, which functions as a cellulose synthesis inhibitor. Thaxtomin A production is controlled by the cluster-situated regulator TxtR, which activates expression of the thaxtomin biosynthetic genes in response to cello-oligosaccharides. Here, we demonstrate that at least five additional regulatory genes are required for wild-type levels of thaxtomin A production and plant pathogenicity in S. scabies. These regulatory genes belong to the bld gene family of global regulators that control secondary metabolism or morphological differentiation in Streptomyces spp. Quantitative reverse-transcriptase polymerase chain reaction showed that expression of the thaxtomin biosynthetic genes was significantly downregulated in all five bld mutants and, in four of these mutants, this downregulation was attributed to the reduction in expression of txtR. Furthermore, all of the mutants displayed reduced expression of other known or predicted virulence genes, suggesting that the bld genes may function as global regulators of virulence gene expression in S. scabies. PMID:24678834

  18. Acaricide resistance and strategies to mitigate economic impact of the southern cattle fever tick (Rhipicephalus microplus) on livestock production systems in the Americas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND: The southern cattle fever tick (SCFT), Rhipicephalus microplus, is considered the most economically important external parasite of livestock worldwide. SCFT populations resistant to acaricides complicate efforts to enhance the productivity of livestock. Here, acaricide resistance is summ...

  19. The economic importance of acaricides in the control of phytophagous mites and an update on recent acaricide mode of action research.

    PubMed

    Van Leeuwen, Thomas; Tirry, Luc; Yamamoto, Atsushi; Nauen, Ralf; Dermauw, Wannes

    2015-06-01

    Acaricides are one of the cornerstones of an efficient control program for phytophagous mites. An analysis of the global acaricide market reveals that spider mites such as Tetranychus urticae, Panonychus citri and Panonychus ulmi are by far the most economically important species, representing more than 80% of the market. Other relevant mite groups are false spider mites (mainly Brevipalpus), rust and gall mites and tarsonemid mites. Acaricides are most frequently used in vegetables and fruits (74% of the market), including grape vines and citrus. However, their use is increasing in major crops where spider mites are becoming more important, such as soybean, cotton and corn. As revealed by a detailed case study of the Japanese market, major shifts in acaricide use are partially driven by resistance development and the commercial availability of compounds with novel mode of action. The importance of the latter cannot be underestimated, although some compounds are successfully used for more than 30 years. A review of recent developments in mode of action research is presented, as such knowledge is important for devising resistance management programs. This includes spirocyclic keto-enols as inhibitors of acetyl-CoA carboxylase, the carbazate bifenazate as a mitochondrial complex III inhibitor, a novel class of complex II inhibitors, and the mite growth inhibitors hexythiazox, clofentezine and etoxazole that interact with chitin synthase I. PMID:26047107

  20. Amblyomma cajennense (Acari: Ixodidae) tick populations susceptible or resistant to acaricides in the Mexican Tropics.

    PubMed

    Alonso-Díaz, M A; Fernández-Salas, A; Martínez-Ibáñez, F; Osorio-Miranda, J

    2013-10-18

    The objectives of the present study were: (i) to identify the frequency of cattle farms with a cohabitation of Amblyomma cajennense and Rhipicephalus microplus, (ii) to determine the status of susceptibility or resistance to acaricides used in Veracruz, Mexico, on A. cajennense populations and (iii) to identify factors associated with A. cajennense resistant to acaricides. Fifty farms were visited to determine the presence of ticks (A. cajennense and R. microplus) and to collect engorged A. cajennense individuals. From these, 24 A. cajennense populations were evaluated in resistance bioassays using discriminating doses of acaricides. The acaricides tested were organophosphates (chlorpiriphos, coumaphos and diazinon), pyrethroids (flumethrin, deltamethrin and cypermethrin), amidines (amitraz) and fipronil (a broad spectrum N-phenylpyrazole insecticide). A. cajennense infesting bovines were identified in 86% (43/50) of the farms visited, and 100% of the farms sampled (43/43) had cohabitation between R. microplus and A. cajennense. Of the farm owners or managers surveyed, 87.5% could not distinguish the morphological difference between tick genera. Populations of A. cajennense were 100%, 91.7% and 12.5% resistant to diazinon, coumaphos and chlorpyriphos (organophosphates), respectively, and 12.5% to amitraz, as were those susceptible to flumethrin and fipronil. In conclusions, populations of A. cajennense showed a high frequency of resistance to the organophosphates tested and to amitraz. Factors associated with the resistance to acaricides in A. cajennense were not identified. PMID:23827041

  1. Comparative toxicity of acaricides to honey bee (Hymenoptera: Apidae) workers and queens.

    PubMed

    Dahlgren, Lizette; Johnson, Reed M; Siegfried, Blair D; Ellis, Marion D

    2012-12-01

    Acaricides are used to treat honey bee (Apis mellifera L.) colonies to control the varroa mite (Varroa destructor Anderson & Trueman), a worldwide threat to honey bee health. Although acaricides control a serious honey bee parasite and mitigate bee loss, they may cause harm to bees as well. We topically applied five acaricides, each with a different mode of action, to young adult queen and worker bees to generate dose-response curves and LD50. Twenty-four hours after treatment, queens were found to be three-times more tolerant of tau-fluvalinate and six-times more tolerant of thymol than workers when adjusted for body weight differences between workers (108 mg) and queens (180 mg). Queens survived the highest administered doses of fenpyroximate (1620 microg/g) and coumaphos (2700 microg/g) indicating that queens are at least 11-fold more tolerant of coumaphos and at least 54-fold more tolerant of fenpyroximate than workers. However, queens treated with as little as 54 microg/g of fenpyroximate exhibited reduced survival over 6 wk after treatment. Amitraz was the only acaricide tested for which queens were not more tolerant than workers. The striking difference in acaricide tolerance of queen and worker honey bees suggests physiological differences in how the two castes are affected by xenobiotics. PMID:23356051

  2. [Experiences with ivermectin in exotic animals: scabies in camelids (Camelus bactrianus, Lama guanicoe, L. glama) and scabies and roundworms in bears (Thalarctos maritimus and Ursus arctos)].

    PubMed

    Kuntze, A; Kuntze, O

    1991-02-01

    For the control of scabies in tylopodes (L. bactrianus, L. guanicoe, L. glama) and brown bears 0.2 mg/kg body weight (1 ml/50 kg body weight) of Ivermectin subcutaneously injected proved to be remedy of choice. In Kodiak-bears the oral application of Ivomec-solution was effective against ascariasis, not, however, in polar bears. Sufficient effect was reached only once, whereas Equalan-paste proved to be highly effective. Despite of strong hygienic measures continous follow-up treatment for the prevention of re-invasion is indispensible. PMID:2025214

  3. First report of a Rhipicephalus microplus tick population multi-resistant to acaricides and ivermectin in the Mexican tropics

    Microsoft Academic Search

    A. Fernández-Salas; R. I. Rodríguez-Vivas; M. A. Alonso-Díaz

    We document the presence of a Rhipicephalus microplus tick population resistant to acaricides (organophosphates (OP), synthetic pyrethroids (SP), amitraz) and macrocyclic lactones (ML) (ivermectin). Engorged females of R. microplus were collected from a cattle farm in Veracruz, Mexico, to evaluate acaricide and ivermectin resistance. The modified larval packet test (LPT) was used to detect OP (chlorpiriphos and diazinon) and SP

  4. Mode of inheritance of resistance to three new acaricides in the Kanzawa spider mite Tetranychus kanzawai Kishida (Acari:Tetranychidae)

    Microsoft Academic Search

    Kouichi Goka

    1998-01-01

    The genetics of resistance to three new types of acaricide tebufenpyrad, fenpyroximate and pyridaben was studied by crossing a resistant (R) with a susceptible (S) strain of Tetranychus kanzawai Kishida. The resistance ratios calculated from the LC50s of the R and S strains were 97, 1265 and 134 for tebufenpyrad, fenpyroximate and pyridaben, respectively. The responses to the three acaricides

  5. Mitigation of Resistance Through Mixtures of Traditional Pesticides, Anti-tick Vaccines, and New Acaricides Developed by the Pharmaceutical Industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the past 70 years, the southern cattle tick, Rhipicephalus (Boophilus) microplus, has developed resistance to every acaricide available for its control. Recently, populations of R. microplus have evolved simultaneous resistance to multiple classes of acaricides. These multi-resistant population...

  6. Acute morbidity associated with scabies and other ectoparasitoses rapidly improves after treatment with ivermectin.

    PubMed

    Worth, Christine; Heukelbach, Jorg; Fengler, Gernot; Walter, Birke; Liesenfeld, Oliver; Hengge, Ulrich; Feldmeier, Hermann

    2012-01-01

    In resource-poor settings, scabies is associated with considerable morbidity. Which factors determine morbidity and how rapidly it recedes after specific treatment is not known. Patients with scabies were recruited in three urban slums in Fortaleza, Northeast Brazil. Diagnosis was established according to dermatoscopy, skin scraping, or adhesive film test. Severity of scabies-associated morbidity was assessed semiquantitatively. Patients and close contacts were treated with oral ivermectin (200 ?g/kg, repeated after 7 days) and followed up for 2 weeks. Ninety-five patients were included in the study. Papules were the most common lesion type (98.9%). Excoriations due to scratching were observed in 43.2% and bacterial superinfection in 24.2%. Predilection sites were the arms (82.1%) and the abdomen (81.1%). At baseline, 36.3% of patients complained about intense or severe itching. Intense or severe itch decreased to 6.3% 2 weeks after treatment (p=0.02). Whereas 37.5% of the patients complained about intense or severe itch-related sleep disturbances at baseline, only 8.8% reported the symptom 2 weeks after treatment (p=0.35). At baseline, the degree of itching was correlated with the degree of sleep disturbance (?=0.64; p<0.001). One week after the first dose of ivermectin, the intensity of itching and of sleep disturbance decreased significantly (p<0.001). In patients living in resource-poor setting, scabies was associated with considerable morbidity. Treatment with ivermectin rapidly reconstituted health in almost all cases. PMID:22211573

  7. Acaricide-impaired functional predation response of the phytoseiid mite Neoseiulus baraki to the coconut mite Aceria guerreronis.

    PubMed

    Lima, D B; Melo, J W S; Gondim, M G C; Guedes, R N C; Oliveira, J E M; Pallini, A

    2015-07-01

    Acaricides may interfere with a myriad of interactions among arthropods, particularly predator-prey interactions. The coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae), and its phytoseiid predator, Neoseiulus baraki (Athias-Henriot) (Acari: Phytoseiidae), provide an opportunity to explore such interference because the former is a key coconut pest species that requires both predation and acaricide application for its management. The objective of the present study was to assess the effect of the acaricides abamectin, azadirachtin and fenpyroximate on the functional response of N. baraki to A. guerreronis densities. The following prey densities were tested: 5, 10, 20, 40 and 80 preys. The type of functional response and prey handling time (Th) were not altered by the acaricides. However, the attack rate (a') was modified by abamectin and fenpyroximate, and the consumption peak was reduced by abamectin. All of the acaricides allowed for the maintenance of the predator in the field, but exposure to abamectin and fenpyroximate compromised prey consumption. PMID:25847106

  8. The efficacy of permethrin 5% vs. oral ivermectin for the treatment of scabies.

    PubMed

    Ranjkesh, Mohammad Reza; Naghili, Behrouz; Goldust, Mohamad; Rezaee, Elham

    2013-01-01

    Human scabies is caused by an infestation of the skin by the human itch mite (Sarcoptes scabiei var. hominis). The aim of this study is to compare the efficacy and safety of permethrin 5% lotion with oral ivermectin for the treatment of scabies. In total, 60 patients with scabies were enrolled, and randomized into two groups: The first group and their family contacts received 5% permethrin cream twice with a one week interval, and the other received a single dose of oral ivermectin. Treatment was evaluated at intervals of 2 and 4 weeks. A single dose of ivermectin provided a cure rate of 62.4%, which increased to 92.8% with 2 doses at a 2-week interval. Treatment with two applications of permethrin with a one week interval was effective in 96.9% of patients. Permethrin-treated patients recovered earlier. Two applications of permethrin with a one week interval is more effective than a single dose of ivermectin. Two doses of ivermectin is as effective as a single application of permethrin. PMID:24791346

  9. Acaricidal activity of five essential oils of Ocimum species on Rhipicephalus (Boophilus) microplus larvae.

    PubMed

    Hüe, T; Cauquil, L; Fokou, J B Hzounda; Dongmo, P M Jazet; Bakarnga-Via, I; Menut, C

    2015-01-01

    The aim of this study was to evaluate the acaricidal activity on the cattle tick Rhipicephalus (Boophilus) microplus of essential oils from three Ocimum species. Acaricidal activity of five essential oils extracted from Ocimum gratissimum L. (three samples), O. urticaefolium Roth, and O. canum Sims was evaluated on 14- to 21-day-old Rhipicephalus microplus tick larvae using larval packet test bioassay. These essential oils were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS) showing great variations of their chemical compositions according to the botanical species and even within the O. gratissimum species; the acaricidal activity of their main compounds was also evaluated. The essential oils of O. urticaefolium and O. gratissimum collected in Cameroon were the most efficient with respective LC50 values of 0.90 and 0.98%. The two essential oils obtained from O. gratissimum collected in New Caledonia were partially active at a dilution of 5% while the essential oil of O. canum collected in Cameroon showed no acaricidal activity. The chemical analysis shows five different profiles. Whereas the essential oils of O. urticaefolium from Cameroon and O. gratissimum from New Caledonia contain high amounts of eugenol (33.0 and 22.3-61.0%, respectively), 1,8-cineole was the main component of the oil of an O. canum sample from Cameroon (70.2%); the samples of O. gratissimum oils from New Caledonia are also characterized by their high content of (Z)-?-ocimene (17.1-49.8%) while the essential oil of O. gratissimum collected in Cameroon is mainly constituted by two p-menthane derivatives: thymol (30.5%) and ?-terpinene (33.0%). Moreover, the essential oil of O. urticaefolium showed the presence of elemicin (18.1%) as original compound. The tests achieved with the main compounds confirmed the acaricidal activity of eugenol and thymol with residual activity until 0.50 and 1%, respectively, and revealed the acaricidal property of elemicin, which was the most efficient compound with 100 % of acaricidal activity at a dilution of 0.25% and could be a valuable acaricide for the control of the cattle tick R. microplus. PMID:25300420

  10. Microarray analysis of acaricide-inducible gene expression in the southern cattle tick, Rhipicephalus (Boophilus) microplus.

    PubMed

    Saldivar, L; Guerrero, F D; Miller, R J; Bendele, K G; Gondro, C; Brayton, K A

    2008-12-01

    Acaricide-inducible differential gene expression was studied in larvae of Rhipicephalus (Boophilus) microplus using a microarray-based approach. The acaricides used were: coumaphos, permethrin, ivermectin, and amitraz. The microarrays contained over 13 000 probes, having been derived from a previously described R. microplus gene index (BmiGI Version 2; Wang et al., 2007). Relative quantitative reverse transcriptase-PCR, real time PCR, and serial analysis of gene expression data was used to verify microarray data. Among the differentially expressed genes with informative annotation were legumain, glutathione S-transferase, and a putative salivary gland-associated protein. PMID:18834453

  11. Scabies outbreaks in residential care homes: factors associated with late recognition, burden and impact. A mixed methods study in England.

    PubMed

    Hewitt, K A; Nalabanda, A; Cassell, J A

    2015-05-01

    Scabies is an important public health problem in residential care homes. Delayed diagnosis contributes to outbreaks, which may be prolonged and difficult to control. We investigated factors influencing outbreak recognition, diagnosis and treatment, and staff experiences of outbreak control, identifying areas for intervention. We carried out a semi-structured survey of managers, affected residents and staff of seven care homes reporting suspected scabies outbreaks in southern England over a 6-month period. Attack rates ranged from 2% to 50%, and most cases had dementia (37/39, 95%). Cases were diagnosed clinically by GPs (59%) or home staff (41%), none by dermatologists. Most outbreaks were attributable to avoidably late diagnosis of the index case. Participants reported considerable challenges in managing scabies outbreaks, including late diagnosis and recognition of outbreaks; logistically difficult mass treatment; distressing treatment processes and high costs. This study demonstrates the need for improved support for care homes in detecting and managing these outbreaks. PMID:25195595

  12. Propolis volatiles characterisation from acaricide-treated and -untreated beehives maintained at Algarve (Portugal)

    Microsoft Academic Search

    Maria G. Miguel; Susana Nunes; Cláudia Cruz; João Duarte; Maria D. Antunes; Ana M. Cavaco; Marta D. Mendes; A. Sofia Lima; Luis G. Pedro; José G. Barroso; A. Cristina Figueiredo

    2012-01-01

    The variability of the volatile profile of 70 propolis samples from acaricide-treated and -untreated beehives maintained at Algarve (Portugal) was evaluated. Propolis samples were collected in three regions of Algarve at three different periods. Cluster analysis based on the propolis volatiles’ chemical composition defined two main clusters, not related to the time of year, collection site, altitude, temperature or humidity

  13. Effect of various acaricides on hatchability of eggs of Rhipicephalus (Boophilus) microplus.

    PubMed

    Haque, M; Jyoti; Singh, N K; Rath, S S

    2014-01-01

    The effect of commonly used acaricides (amitraz, cypermethrin, deltamethrin, fenvalerate, and flumethrin) on the eggs of Rhipicephalus (Boophilus) microplus collected from Ludhiana, Punjab, was evaluated by egg hatch assay (EHA). The regression graph of probit hatchability and per cent inhibition of hatching (IH%) of eggs was plotted against log values of concentration of various acaricides. All concentrations of flumethrin and amitraz caused complete inhibition of hatching, whereas a hatchability of 31.0 ± 6.1, 40.0 ± 5.2 and 19.3 ± 1.7% was only recorded at the highest concentration of cypermethrin, deltamethrin, and fenvalerate, respectively. An increase in the concentration of the acaricide showed a significant effect on the IH% of eggs for cypermethrin (P < 0.01) and deltamethrin (P < 0.05) but was nonsignificant for fenvalerate. The slope of the regression curve of IH% was utilized for the calculation of the dose of various acaricides causing inhibition of hatching for 95% eggs (LC95) and the discriminating dose (DD). Results indicated that maximum DD was recorded for fenvalerate (2.136%), followed by cypermethrin (0.214%) and deltamethrin (0.118%). The results of the current study will be helpful in formulating effective control strategies against ticks. PMID:25057486

  14. Acaricidal Effect of some Pesticides against the Red Spider Mite Oligonychus coffeae Nietner (Tetranychidae)

    Microsoft Academic Search

    R. L. Tripathi; Shri Ram

    1970-01-01

    Six pesticides, viz. dicofol, binapacryl, carbophenothion, lime-sulphur solution, dimethoate and phosalone, each at four different concentrations, were tested against the red spider mite Oligonychus coffeae Nietner. All except lime-sulphur were found to be effective acaricides, and all except lime-sulphur and dimethoate were also ovicidal.

  15. Combination studies of selected acaricides with zineb, mancozeb, or carbamate for mite control on citrus

    Microsoft Academic Search

    Carl C. Childers

    1990-01-01

    Field experiments were conducted between 1981 and 1988 to evaluate the potential of zineb (zinc ethylene bisdithiocarbamate), mancozeb (a coordination product of zinc ion and manganese ethylene bisdithiocarbamate) and carbamate (ferric dimethyldithiocarbamate) in combination with one or more of the following acaricides: ethion, chlorpyrifos, dicofol, chlorobenzilate, propargite or formetanate for the control of the citrus rust mite, Phyllocoptruta oleivora (Ashmead)

  16. The use of surfactants to enhance acaricide control of Phytonemus pallidus (Acari: Tarsonemidae) in strawberry

    Microsoft Academic Search

    Michelle T. Fountain; Adrian L. Harris; Jerry V. Cross

    2010-01-01

    The tarsonemid mite, Phytonemus (Tarsonemus) pallidus ssp. fragariae (Zimmerman), is a serious pest of strawberry throughout much of Europe and North America. Many of the plant protection products previously effective against the mite, which causes stunting and distorting of leaves and buds, reducing fruit yield and quality, are no longer available. Finding alternative acaricides for control is a priority. In

  17. Plant essential oils and formamidines as insecticides/ acaricides: what are the molecular targets?

    E-print Network

    Plant essential oils and formamidines as insecticides/ acaricides: what are the molecular targets to combat Varroa mites. Nowadays, mainly plant essential oils and organic acids are applied because they are safer and impose less unfavorable effects on the environment. Essential oils contain mixtures of mostly

  18. Acaricidal activity of 31 essential oils extracted from plants collected in Tunisia

    Microsoft Academic Search

    Sabrine Attia; Kaouthar L. Grissa; Zeineb G. Ghrabi; Anne C. Mailleux; Georges Lognay; Thierry Hance

    2012-01-01

    The two-spotted spider mite Tetranychus urticae Koch is a worldwide pest, feeding on a large variety of plant families. As its resistance to acaricides spreads rapidly, it is crucial to develop new biological control tactics to manage its populations. In this respect, essential oils may be a good alternative, as they are currently considered minimum-risk pesticides. In this paper, we

  19. Treatment of scabies: the topical ivermectin vs. permethrin 2.5% cream.

    PubMed

    Goldust, Mohamad; Rezaee, Elham; Raghifar, Ramin; Hemayat, Sevil

    2013-01-01

    Human scabies is caused by an infestation of the skin by the human itch mite (Sarcoptes scabiei va. hominis). It is commonly treated with topical insecticides, but the treatment of choice is still controversial. The aim of this study is to compare the efficacy of topical ivermectin vs. permethrin 2.5% cream for the treatment of scabies. In total, 380 patients with scabies were enrolled, and randomized into two groups: the first group received 1% ivermectin applied topically to the affected skin at a dose of 400 microg/kg, repeated once the following week, while the second group received permethrin 2.5% cream and were told to apply this twice at one week intervals. Treatment was evaluated at intervals of 2 and 4 weeks, and if there was treatment failure at the 2-week follow-up, treatment was repeated. Two applications of topical ivermectin provided a cure rate of 63.1% at the 2-week follow-up, which increased to 84.2% at the 4-week follow-up after repeating the treatment. Treatment with two applications of permethrin 2.5% cream with a 1-week interval between them was effective in 65.8% of patients at the 2-week follow-up, which increased to 89.5% at the 4-week follow-up after this treatment was repeated. Two application of ivermectin was as effective as two applications of permethrin 2.5% cream at the 2-week follow-up. After repeating the treatment, ivermectin was as effective as permethrin 2.5% cream at the 4-week follow up. PMID:24171301

  20. A Scabies Mite Serpin Interferes with Complement-Mediated Neutrophil Functions and Promotes Staphylococcal Growth

    PubMed Central

    Swe, Pearl M.; Fischer, Katja

    2014-01-01

    Background Scabies is a contagious skin disease caused by the parasitic mite Sarcoptes scabiei. The disease is highly prevalent worldwide and known to predispose to secondary bacterial infections, in particular by Streptococcus pyogenes and Staphylococcus aureus. Reports of scabies patients co-infected with methicillin resistant S. aureus (MRSA) pose a major concern for serious down-stream complications. We previously reported that a range of complement inhibitors secreted by the mites promoted the growth of S. pyogenes. Here, we show that a recently characterized mite serine protease inhibitor (SMSB4) inhibits the complement-mediated blood killing of S. aureus. Methodology/Principal Findings Blood killing of S. aureus was measured in whole blood bactericidal assays, counting viable bacteria recovered after treatment in fresh blood containing active complement and phagocytes, treated with recombinant SMSB4. SMSB4 inhibited the blood killing of various strains of S. aureus including methicillin-resistant and methicillin-sensitive isolates. Staphylococcal growth was promoted in a dose-dependent manner. We investigated the effect of SMSB4 on the complement-mediated neutrophil functions, namely phagocytosis, opsonization and anaphylatoxin release, by flow cytometry and in enzyme linked immuno sorbent assays (ELISA). SMSB4 reduced phagocytosis of S. aureus by neutrophils. It inhibited the deposition of C3b, C4b and properdin on the bacteria surface, but did not affect the depositions of C1q and MBL. SMSB4 also inhibited C5 cleavage as indicated by a reduced C5b-9 deposition. Conclusions/Significance We postulate that SMSB4 interferes with the activation of all three complement pathways by reducing the amount of C3 convertase formed. We conclude that SMSB4 interferes with the complement-dependent killing function of neutrophils, thereby reducing opsonization, phagocytosis and further recruitment of neutrophils to the site of infection. As a consequence secreted scabies mites complement inhibitors, such as SMSB4, provide favorable conditions for the onset of S. aureus co-infection in the scabies-infected microenvironment by suppressing the immediate host immune response. PMID:24945501

  1. Determination of Acaricide Residues in Saudi Arabian Honey and Beeswax Using Solid Phase Extraction and Gas Chromatography

    Microsoft Academic Search

    ALAA KAMEL; AHMAD AL-GHAMDI

    2006-01-01

    Determination of acaricide residues of flumethrin, tau-fluvalinate, coumaphos, and amitraz in honey and beeswax was carried out using a rapid extraction method utilizing C-18 SPE cartridges and an analytical method utilizing GC with ECD, NPD, and MSD detectors for the four acaricides. Recovery percentages from the extraction method ranged from 90–102%, while the minimum detection levels ranged from 0.01–0.05 mg\\/kg

  2. Selection and Characterization of Microorganisms Utilizing Thaxtomin A, a Phytotoxin Produced by Streptomyces scabies

    PubMed Central

    Doumbou, Cyr Lézin; Akimov, Vladimir; Beaulieu, Carole

    1998-01-01

    Thaxtomin A is the main phytotoxin produced by Streptomyces scabies, a causal agent of potato scab. Thaxtomin A is a yellow compound composed of 4-nitroindol-3-yl-containing 2,5-dioxopiperazine. A collection of nonpathogenic streptomycetes isolated from potato tubers and microorganisms recovered from a thaxtomin A solution were examined for the ability to grow in the presence of thaxtomin A as a sole carbon or nitrogen source. Three bacterial isolates and two fungal isolates grew in thaxtomin A-containing media. Growth of these organisms resulted in decreases in the optical densities at 400 nm of culture supernatants and in 10% reductions in the thaxtomin A concentration. The fungal isolates were identified as a Penicillium sp. isolate and a Trichoderma sp. isolate. One bacterial isolate was associated with the species Ralstonia pickettii, and the two other bacterial isolates were identified as Streptomyces sp. strains. The sequences of the 16S rRNA genes were determined in order to compare thaxtomin A-utilizing actinomycetes to the pathogenic organism S. scabies and other Streptomyces species. The nucleotide sequences of the ? variable regions of the 16S ribosomal DNA of both thaxtomin A-utilizing actinomycetes were identical to the sequence of Streptomyces mirabilis ATCC 27447. When inoculated onto potato tubers, the three thaxtomin A-utilizing bacteria protected growing plants against common scab, but the fungal isolates did not have any protective effect. PMID:9797282

  3. Selection and characterization of microorganisms utilizing thaxtomin A, a phytotoxin produced by streptomyces scabies

    PubMed

    Doumbou; Akimov; Beaulieu

    1998-11-01

    Thaxtomin A is the main phytotoxin produced by Streptomyces scabies, a causal agent of potato scab. Thaxtomin A is a yellow compound composed of 4-nitroindol-3-yl-containing 2,5-dioxopiperazine. A collection of nonpathogenic streptomycetes isolated from potato tubers and microorganisms recovered from a thaxtomin A solution were examined for the ability to grow in the presence of thaxtomin A as a sole carbon or nitrogen source. Three bacterial isolates and two fungal isolates grew in thaxtomin A-containing media. Growth of these organisms resulted in decreases in the optical densities at 400 nm of culture supernatants and in 10% reductions in the thaxtomin A concentration. The fungal isolates were identified as a Penicillium sp. isolate and a Trichoderma sp. isolate. One bacterial isolate was associated with the species Ralstonia pickettii, and the two other bacterial isolates were identified as Streptomyces sp. strains. The sequences of the 16S rRNA genes were determined in order to compare thaxtomin A-utilizing actinomycetes to the pathogenic organism S. scabies and other Streptomyces species. The nucleotide sequences of the gamma variable regions of the 16S ribosomal DNA of both thaxtomin A-utilizing actinomycetes were identical to the sequence of Streptomyces mirabilis ATCC 27447. When inoculated onto potato tubers, the three thaxtomin A-utilizing bacteria protected growing plants against common scab, but the fungal isolates did not have any protective effect. PMID:9797282

  4. The potential of middle eastern flora as a source of new safe bio-acaricides to control Tetranychus cinnabarinus , the carmine spider mite

    Microsoft Academic Search

    F. Mansour; H. Azaizeh; B. Saad; Y. Tadmor; F. Abo-Moch; O. Said

    2004-01-01

    Twenty-nine plant extracts of local species were evaluated for their potential as a source of bioactive ingredients with significant\\u000a acaricidal activity that could lead to the development of new and safe bio-acaricides. The crude extracts (70% ethanol) of\\u000a these plants were tested for their acaricidal activity against the carmine spider miteTetranychus cinnabarinus in a bioassay under controlled conditions. Mortality, repellency,

  5. The AraC/XylS regulator TxtR modulates Thaxtomin Biosynthesis and Virulence in Streptomyces scabies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Streptomyces scabies is the best studied of those streptomycetes that cause an economically important disease known as potato scab. The phytotoxin thaxtomin is made exclusively by these pathogens and is required for virulence. Here we describe regulation of thaxtomin biosynthesis by TxtR, a member...

  6. THE RISE AND FALL OF PSOROPTIC SCABIES IN BIGHORN SHEEP IN THE SAN ANDRES MOUNTAINS, NEW MEXICO

    Microsoft Academic Search

    Walter M. Boyce; Mara E. Weisenberger

    2005-01-01

    Between 1978 and 1997, a combination of psoroptic scabies (Psoroptes spp.), moun- tain lion (Puma concolor) predation, and periodic drought reduced a population of native desert bighorn sheep (Ovis canadensis) in the San Andres Mountains (SAM), New Mexico, from .200 individuals to a single ewe. In 1999, this ewe was captured, ensured to be Psoroptes-free, and released back into the

  7. Toxicodynamic mechanisms and monitoring of acaricide resistance in the two-spotted spider mite.

    PubMed

    Kwon, Deok Ho; Clark, J Marshall; Lee, Si Hyeock

    2015-06-01

    The two-spotted spider (Tetranychus urticae) is one of the most serious pests world-wide and has developed resistance to many types of acaricides. Various mutations on acaricide target site genes have been determined to be responsible for toxicodynamic resistance, and the genotyping and frequency prediction of these mutations can be employed as an alternative resistance monitoring strategy. A quantitative sequencing (QS) protocol was reported as a population-based genotyping technique, and applied for the determination of resistance allele frequencies in T.?urticae field populations. In addition, a modified glass vial bioassay method (residual contact vial bioassay, RCV) was implemented as a rapid on-site resistance monitoring tool. The QS protocol, together with the RCV, would greatly facilitate monitoring of T.?urticae resistance. Recent completion of T.?urticae genome analysis should facilitate the identification of additional resistance genetic markers that can be employed for molecular resistance monitoring. PMID:26047116

  8. Insecticide/acaricide resistance in fleas and ticks infesting dogs and cats

    PubMed Central

    2014-01-01

    This review defines insecticide/acaricide resistance and describes the history, evolution, types, mechanisms, and detection of resistance as it applies to chemicals currently used against fleas and ticks of dogs and cats and summarizes resistance reported to date. We introduce the concept of refugia as it applies to flea and tick resistance and discuss strategies to minimize the impact and inevitable onset of resistance to newer classes of insecticides. Our purpose is to provide the veterinary practitioner with information needed to investigate suspected lack of efficacy, respond to lack of efficacy complaints from their clients, and evaluate the relative importance of resistance as they strive to relieve their patients and satisfy their clients when faced with flea and tick infestations that are difficult to resolve. We conclude that causality of suspected lack of insecticide/acaricide efficacy is most likely treatment deficiency, not resistance. PMID:24393426

  9. Acaricidal efficacy against cattle ticks and acute oral toxicity of Lippia javanica (Burm F.) Spreng

    Microsoft Academic Search

    James Madzimure; Emmanuel T. Nyahangare; Humphrey Hamudikuwanda; Thokozani Hove; Philip C. Stevenson; Steve R. Belmain; Brighton M. Mvumi

    2011-01-01

    In search for low-cost, safe and environmentally benign plant-based alternatives to commercial pesticides, the efficacy of\\u000a Lippia javanica aqueous leaf extracts in controlling ticks on cattle, acute oral toxicity in mice and phytochemistry were evaluated. L. javanica aqueous leaf extracts at 10% and 20% w\\/v were effective at controlling cattle ticks but not as good as an amitraz-based acaricide Tickbuster®.

  10. Toxicity of some insecticides and acaricides to the predatory bug Dicyphus tamaninii (Het.: Miridae)

    Microsoft Academic Search

    C. CASTAIqI; J. Arino; J. Arno

    1996-01-01

    Several pesticides were tested in the laboratory for their side-effects upon the mirid bugDicyphus tamaninii, a polyphagous predator used for IPM programmes in some vegetable crops. Residual toxicity to 3rd -4th instar nymphs on tomato\\u000a leaflets was checked 24, 48 hours and seven days after treatment. The acaricides bromopropylate, dicofol+tetradifon and fenpyroximate\\u000a were harmless to the nymphs. The insect growth

  11. Development of acaricide resistance in Pacific spider mite ( Tetranychus pacificus ) from California vineyards

    Microsoft Academic Search

    Menelaos C. Stavrinides; Pieter Van Nieuwenhuyse; Thomas Van Leeuwen; Nicholas J. Mills

    2010-01-01

    In recent years, grape growers in California reported failures of acaricides against Tetranychus pacificus McGregor. We collected T. pacificus populations from four vineyards and tested them for resistance to bifenazate, propargite and pyridaben. In addition, we sequenced\\u000a part of the cytochrome b gene of bifenazate-resistant and -susceptible T. pacificus to test for the presence of mutations reported to confer resistance

  12. Determination of Degradation Rate of Acaricide Fenpyroximate in Apple, Citrus, and Grape by HPLC-DAD

    Microsoft Academic Search

    Sherif H. Abd Al-Rahman; M. M. Almaz; I. A. Osama

    Fenpyroximate, a widely used acaricide around the world, was recently registered for control of mites in Egypt. Hence, only\\u000a limited data are available on the dissipation rate of fenpyroximate under field conditions. In this study the dissipation\\u000a rate of fenpyroximate after one application on apple, citrus and grape was estimated. Samples were prepared by an optimized\\u000a quick, easy, cheap, effective,

  13. Acaricidal, repellent and oviposition deterrent activities of Datura stramonium L. against adult Tetranychus urticae (Koch)

    Microsoft Academic Search

    Nabi Alper Kumral; Sultan Çobano?lu; Cem Yalcin

    2010-01-01

    The ethanol extracts obtained from both leaf and seed in the Thorn apple (Datura stramonium L.) (Solanaceae) were investigated for acaricidal, repellent and oviposition deterrent properties against adult two-spotted\\u000a spider mites (Tetranychus urticae Koch) (Acari: Tetranychidae) under laboratory conditions. Leaf and seed extracts, which were applied in 167,250 and 145,750 mg\\/l\\u000a concentrations, respectively (using a Petri leaf disc-spray tower method), caused

  14. Degradation of the acaricides abamectin, flufenoxuron and amitraz on Saudi Arabian dates

    Microsoft Academic Search

    Alaa Kamel; Saleh Al-Dosary; Samy Ibrahim; Mohammed Asif Ahmed

    2007-01-01

    Degradation of the acaricides abamectin, flufenoxuron and amitraz on date palms, Phoenix dactylefera var. Nabout Seif, grown in Saudi Arabia was studied during the post-harvest interval (PHI) under the local weather and soil conditions. The initial deposit of abamectin residues on dates was 0.09mg\\/kg, which declined to 0.03 (66%) and 0.02mg\\/kg (88%) after 7 and 14 days of spraying, respectively

  15. Acaricide Residues in Laying Hens Naturally Infested by Red Mite Dermanyssus gallinae

    PubMed Central

    Marangi, Marianna; Morelli, Vincenzo; Pati, Sandra; Camarda, Antonio; Cafiero, Maria Assunta; Giangaspero, Annunziata

    2012-01-01

    In the poultry industry, control of the red mite D. gallinae primarily relies worldwide on acaricides registered for use in agriculture or for livestock, and those most widely used are carbamates, followed by amidines, pyrethroids and organophosphates. Due to the repeated use of acaricides - sometimes in high concentrations - to control infestation, red mites may become resistant, and acaricides may accumulate in chicken organs and tissues, and also in eggs. To highlight some situations of misuse/abuse of chemicals and of risk to human health, we investigated laying hens, destined to the slaughterhouse, for the presence of acaricide residues in their organs and tissues. We used 45 hens from which we collected a total of 225 samples from the following tissues and organs: skin, fat, liver, muscle, hearth, and kidney. In these samples we analyzed the residual contents of carbaryl and permethrin by LC-MS/MS. Ninety-one (40.4%) samples were positive to carbaryl and four samples (1.7%) were positive to permethrin. Concentrations of carbaryl exceeding the detection limit (0.005 ppm) were registered in the skin and fat of birds from two farms (p<0.01), although these concentrations remained below the maximum residue limit (MRLs) (0.05 ppm) (p<0.01). All organs/tissues of hens from a third farm were significantly more contaminated, with skin and muscle samples exceeding the MRL (0.05 ppm) (p<0.01) of carbaryl in force before its use was banned. Out of 45 chickens tested, 37 (82.2%) were found to be contaminated by carbaryl, and 4 (8.8%) by permethrin. The present study is the first report on the presence of pesticides banned by the EU (carbaryl) or not licensed for use (permethrin) in the organs and tissues of laying hens, which have been treated against red mites, and then slaughtered for human consumption at the end of their life cycle. PMID:22363736

  16. Toxicity and efficacy of selected pesticides and new acaricides to stored product mites (Acari: Acaridida)

    Microsoft Academic Search

    Jan Hubert; Vaclav Stejskal; Zuzana Munzbergova; Jana Hajslova; Frank H. Arthur

    2007-01-01

    Stored product mites can often infest stored products, but currently there is little information regarding the efficacy of\\u000a pesticides that can be used for control. In this study we evaluated several common pesticides formulated from single active\\u000a ingredients (a.i.) or commercially available mixtures (chlorpyrifos, deltamethrin, beta-cyfluthrin, and a combination of deltamethrin\\u000a and S-bioallethrin), plus an acaricide composed of permethrin, pyriproxyfen

  17. Acaricide residues in laying hens naturally infested by red mite Dermanyssus gallinae.

    PubMed

    Marangi, Marianna; Morelli, Vincenzo; Pati, Sandra; Camarda, Antonio; Cafiero, Maria Assunta; Giangaspero, Annunziata

    2012-01-01

    In the poultry industry, control of the red mite D. gallinae primarily relies worldwide on acaricides registered for use in agriculture or for livestock, and those most widely used are carbamates, followed by amidines, pyrethroids and organophosphates. Due to the repeated use of acaricides--sometimes in high concentrations--to control infestation, red mites may become resistant, and acaricides may accumulate in chicken organs and tissues, and also in eggs. To highlight some situations of misuse/abuse of chemicals and of risk to human health, we investigated laying hens, destined to the slaughterhouse, for the presence of acaricide residues in their organs and tissues. We used 45 hens from which we collected a total of 225 samples from the following tissues and organs: skin, fat, liver, muscle, hearth, and kidney. In these samples we analyzed the residual contents of carbaryl and permethrin by LC-MS/MS.Ninety-one (40.4%) samples were positive to carbaryl and four samples (1.7%) were positive to permethrin. Concentrations of carbaryl exceeding the detection limit (0.005 ppm) were registered in the skin and fat of birds from two farms (p<0.01), although these concentrations remained below the maximum residue limit (MRLs) (0.05 ppm) (p<0.01). All organs/tissues of hens from a third farm were significantly more contaminated, with skin and muscle samples exceeding the MRL (0.05 ppm) (p<0.01) of carbaryl in force before its use was banned. Out of 45 chickens tested, 37 (82.2%) were found to be contaminated by carbaryl, and 4 (8.8%) by permethrin. The present study is the first report on the presence of pesticides banned by the EU (carbaryl) or not licensed for use (permethrin) in the organs and tissues of laying hens, which have been treated against red mites, and then slaughtered for human consumption at the end of their life cycle. PMID:22363736

  18. Repellents and acaricides as personal protection measures in the prevention of tick-borne diseases.

    PubMed

    Cisak, Ewa; Wójcik-Fatla, Angelina; Zaj?c, Violetta; Dutkiewicz, Jacek

    2012-01-01

    A number of preventive measures for the protection of humans against tick-borne diseases were evaluated. Measures involving the avoidance of tick bites with the use of protective clothing and insect repellents are the simplest and most effective. Repellents are applied directly to the skin or clothing and other fabrics, such as bednets, tents and anti-mosquito screens. Currently, DEET (N,N-diethyl-m-toluamide) is considered the most efficient arthropod repellent reference substance. The registered and recommended active repellent ingredients for skin and/or cloths application, among others, are: DEET, 1-methyl-propyl-2- (hydroxyethyl)-1-piperidinecarboxylate (picaridin), p-menthane-3,8-diol (PMD), ethyl butylactyloaminopropionate ( IR3535), 1S,2S-2-methylpiperidinyl-3-cyclohexene-1-carboxamide (SS220), racemic 2-methylpiperidinyl-3-cyclohexene-1-carboxamide (AI3-37220) and synthethic pyrethroid - 3-phenoxybenzyl-cis-trans-3(2,2 dichlorovinyl)-2,2-dimethylcyclopropancarboxylate (permethrin) - an acaricide with repellent properties. To achieve the protection from tick bites by avoiding attachment and/or engorgement by the arthropod, acaricides with repellent properties, such as synthetic pyrethroid-permethrin are used. This pyrethroid is an acaricide of choice used for clothing impregnation, which is effective for personal protection against all three parasitic stages of western black-legged ticks. Products based on natural compounds, e.g. eugenol from Ocimum basilicum, 2-undecanone originally derived from wild tomato, geraniol - a natural product extracted from plants, and many others, represent an interesting alternative to common synthetic repellents and/or acaricides. PMID:23311778

  19. Efficacy of tags impregnated with pheromone and acaricide for control of Amblyomma variegatum.

    PubMed

    Allan, S A; Barré, N; Sonenshine, D E; Burridge, M J

    1998-04-01

    The efficacy of tags impregnated with pheromone and acaricide for control of Amblyomma variegatum on cattle in Guadeloupe was determined for a 13-week trial. Comparisons were made between untreated cattle and cattle with tags containing either pheromones alone (o-nitrophenol, methyl salicylate, 2,6-dichlorophenol and phenylacetaldehyde), pheromones plus acaricide (cyfluthrin or deltamethrin), or acaricide alone. Tags were fastened to cattle both on collars on the neck and with adhesive to tail hairs, with over 98 and 90% of tags retained, respectively, during the trial. By the end of the trial, tick infestations increased on untreated cattle (311.7%) and cattle with pheromone tags (154.8%) but decreased on cattle with pheromone/ cyfluthrin (-45.0%), cyfluthrin (-42.8%), pheromone/deltamethrin (-68.7%) and deltamethrin tags (-87.6%). Cattle with pheromone tags had greater proportions of ticks on the hind regions (81%) compared to untreated cattle (62.5%) and on the front regions (18.2%) compared to untreated cattle (8.2%) indicating that ticks aggregated in response to pheromones. Analysis of hair samples by gas chromatography indicated that, within 2 days of placement, cyfluthrin spread rapidly over the body from the tags. Both cyfluthrin and deltamethrin were present in detectable levels on all eight body regions examined throughout the trial. Analysis of the tags indicated that they all still contained pheromone components after 13 weeks under field conditions. PMID:9622367

  20. Acaricidal effect of Cassia fistula Linn. leaf ethanolic extract against Rhipicephlaus (Boophilus) annulatus.

    PubMed

    Sunil, A R; Amithamol, K K; Juliet, S; Nair, S N; Ajithkumar, K G; Soorya, V C; Divya, T M; Jyothymol, G; Ghosh, S; Ravindran, R

    2013-06-01

    The present study evaluates the acaricidal properties of crude ethanolic extract of Cassia fistula leaves for controlling Rhipicephalus (Boophilus) annulatus based on adult immersion test (AIT). The percentage of adult mortality, inhibition of fecundity and hatching of ova laid were studied at different concentrations of the extract ranging from 50 to 100 mg / ml. The results were compared using one-way ANOVA. The extract produced complete inhibition of hatching of eggs at concentrations above 80 mg / ml of the extract. Mortality of adult engorged female ticks and inhibition of fecundity were concentration dependent. The LC50 value of extract against R. (B.) annulatus was 97.1 mg / ml. PMID:23959488

  1. Acaricidal activity of cinnamaldehyde and its congeners against Tyrophagus putrescentiae (Acari: Acaridae)

    Microsoft Academic Search

    Hyun-Kyung Kim; Jun-Ran Kim; Young-Joon Ahn

    2004-01-01

    The acaricidal activity of cinnamaldehyde and its 11 congeners against adults of Tyrophagus putrescentiae was examined using direct contact application and fumigation methods and compared with that of benzyl benzoate, N,N-diethyl-m-toluamide (DEET) and dibutyl phthalate. On the basis of 24h LD50 values, the compound most toxic to T. putrescentiae was cinnamyl acetate (0.89?g\\/cm2) followed by cinnamaldehyde (1.12?g\\/cm2), benzaldehyde (1.93?g\\/cm2), 3-phenylpropionaldehyde

  2. Rhipicephalus (Boophilus) microplus resistant to acaricides and ivermectin in cattle farms of Mexico.

    PubMed

    Rodríguez-Vivas, Róger Iván; Pérez-Cogollo, Luis Carlos; Rosado-Aguilar, José Alberto; Ojeda-Chi, Melina Maribel; Trinidad-Martinez, Iris; Miller, Robert John; Li, Andrew Yongsheng; de León, Adalberto Pérez; Guerrero, Félix; Klafke, Guilherme

    2014-01-01

    Ticks and the diseases they transmit cause great economic losses to livestock in tropical countries. Non-chemical control alternatives include the use of resistant cattle breeds, biological control and vaccines. However, the most widely used method is the application of different chemical classes of acaricides and macrocyclic lactones. Populations of the cattle tick, Rhipicephalus (Boophilus) microplus, resistant to organophosphates (OP), synthetic pyrethroids (SP), amitraz and fipronil have been reported in Mexico. Macrocyclic lactones are the most sold antiparasitic drug in the Mexican veterinary market. Ivermectin-resistant populations of R. (B.) microplus have been reported in Brazil, Uruguay and especially in Mexico (Veracruz and Yucatan). Although ivermectin resistance levels in R. (B.) microplus from Mexico were generally low in most cases, some field populations of R. (B.) microplus exhibited high levels of ivermectin resistance. The CHPAT population showed a resistance ratio of 10.23 and 79.6 at lethal concentration of 50% and 99%, respectively. Many field populations of R. (B.) microplus are resistant to multiple classes of antiparasitic drugs, including organophosphates (chlorpyrifos, coumaphos and diazinon), pyrethroids (flumethrin, deltamethrin and cypermethrin), amitraz and ivermectin. This paper reports the current status of the resistance of R. (B.) microplus to acaricides, especially ivermectin, in Mexican cattle. PMID:25054487

  3. [Compatibility of Beauveria bassiana (Ascomycetes: Clavicipitaceae) with chemicals acaricides used in the control of cattle tick].

    PubMed

    Barci, Leila A G; Wenzel, Inajá M; de Almeida, José Eduardo M; de Campos Nogueira, Adriana H; do Prado, Angelo P

    2009-12-01

    The purpose of the present study was to assess compatibility between IBCB66 and IBCB21 isolates of Beauveria bassiana and acaricides: Flumethrin+Coumaphos, Deltamethrin, Dichlorvos+Cypermethrin, Dichlorvos+Chlorpyrifos, Cypermethrin High Cis, Dichlorvos+Cypermethrin High Cis, Cypermethrin and Amitraz, utilized on the control of Rhipicephalus (Boophilus) microplus in our country. The effect of commercial products on the isolates was assayed according to observation of vegetative growth, conidia production, and viability of strains of B. bassiana fungus. With concerning about IBCB66 isolate, products Deltamethrin, Cypermethrin High Cis and Amitraz were compatible, not affecting the entomopathogen development. Product Cypermethrin was toxic, and products Flumethrin+Coumaphos, Dichlorvos+Cypermethrin, Dichlorvos+Chlorpyrifos and Dichlorvos+Cypermethrin High Cis were very toxic. In regard to IBCB21 isolate, products Flumethrin+Coumaphos, Dichlorvos+Cypermethrin, Dichlorvos+Chlorpyrifos, Cypermethrin High Cis, Dichlorvos+Cypermethrin High Cis and Cypermethrin were very toxic and product Amitraz was toxic. From the acaricides evaluated, product Deltamethrin was the single agent that did not produce toxic effect on the entomopathogen. PMID:20040194

  4. Acaricidal activity of aqueous extract and synthesized silver nanoparticles from Manilkara zapota against Rhipicephalus (Boophilus) microplus.

    PubMed

    Rajakumar, G; Abdul Rahuman, A

    2012-08-01

    Traditional parasite control is primarily based on the use of chemical acaricides, which unfortunately have many negative side effects. The aim of the present study was to evaluate the effect of plant synthesized silver nanoparticles (AgNPs) using aqueous leaf extract of Manilkara zapota to control Rhipicephalus (Boophilus) microplus. The synthesized AgNPs were characterized by UV-vis spectrum, scanning electron microscopy (SEM), Fourier transform infrared and X-ray diffraction. The UV-vis spectrum of the aqueous medium containing silver nanostructures showed a peak at 421 nm corresponding to the surface plasmon resonance band of AgNPs. SEM supports the biosynthesis and characterization of AgNPs with spherical and oval in shape and size of 70-140 nm. Acaricidal activity of aqueous leaf extract of M. zapota and synthesized AgNPs were carried out against R. (B.) microplus and the results showed the LC(50) values of 16.72 and 3.44 mg/L; r(2)=0.856 and 0.783), respectively. PMID:21906765

  5. Acaricidal activity of constituents identified in Foeniculum vulgare fruit oil against Dermatophagoides spp. (Acari: Pyroglyphidae).

    PubMed

    Lee, Hoi-Seon

    2004-05-19

    Acaricidal activities of components derived from Foeniculum vulgare fruit oil against Dermatophagoides farinae and Dermatophagoides pteronyssinus were examined using direct contact application and compared with that of the commercial repellent benzyl benzoate. The major biologically active constituent of Foeniculum fruit oil was characterized as (+)-fenchone by spectroscopic analyses. On the basis of LD(50) values, the compound most toxic to D. farinae was p-anisaldehyde (11.3 mg/m(2)) followed by (+)-fenchone (38.9 mg/m(2)), (-)-fenchone (41.8 mg/m(2)), benzyl benzoate (89.2 mg/m(2)), thymol (90.3 mg/m(2)), and estragol (413.3 mg/m(2)). Against D. pteronyssinus, p-anisaldehyde (10.1 mg/m(2)) was much more effective than benzyl benzoate (67.5 mg/m(2)), thymol (68.5 mg/m(2)), and estragol (389.9 mg/m(2)). These results indicate that the acaricidal activity of F. vulgare fruit oil likely results from (+)-fenchone and p-anisaldehyde. (+)-Fenchone was 20.3 times more abundant in the oil than p-anisaldehyde. (+)-Fenchone and p-anisaldehyde merit further study as potential house dust mite control agents or as lead compounds. PMID:15137830

  6. Determination of acaricide residues in saudi arabian honey and beeswax using solid phase extraction and gas chromatography.

    PubMed

    Kamel, Alaa; Al-Ghamdi, Ahmad

    2006-01-01

    Determination of acaricide residues of flumethrin, tau-fluvalinate, coumaphos, and amitraz in honey and beeswax was carried out using a rapid extraction method utilizing C-18 SPE cartridges and an analytical method utilizing GC with ECD, NPD, and MSD detectors for the four acaricides. Recovery percentages from the extraction method ranged from 90-102%, while the minimum detection levels ranged from 0.01-0.05 mg/kg for the acaricides. Nine of the 21 analyzed samples were found to be contaminated with the acaricides tau-fluvalinate and coumaphos. Neither flumethrin nor amitraz was detected in any of the honey or wax samples. Coumaphos was found only in honey samples in which two samples exceeded the tolerance levels set by EPA and EC regulations. It has not been detected in beeswax. Five honey samples and eight beeswax samples were found to be contaminated with tau-fluvalinate. One of the wax samples was contaminated with a relatively high residue of tau-fluvalinate and contained above 10 mg/kg. PMID:16393903

  7. Susceptibility of the red spider mite, Oligonychus coffeae (Acari: Tetranychidae), to acaricides on tea plants in Japan

    Microsoft Academic Search

    T. Gotoh; Y. Kitashima; K. Goka; T. Nagata

    2001-01-01

    The red spider mite, Oligonychus coffeae (Nietner) (Tetranychidae), was recently found on mango and tea plants in the Ryukyu Islands, southern Japan. The susceptibility of adult females and eggs of a population from tea on Okinawa Island to 19 acaricides was examined, using a spray tower. The LC50 values in female adults of O. coffeae indicated high susceptibility to 15

  8. Cross-resistance, inheritance, and biochemistry of mitochondrial electron transport inhibitor-acaricide resistance in Tetranychus urticae (Acari: Tetranychidae).

    PubMed

    Stumpf, N; Nauen, R

    2001-12-01

    Resistance of the twospotted spider mite, Tetranychus urticae Koch, to acaricides acting as mitochondrial electron transport inhibitors (METIs) is an increasing problem. Because of their high levels of cross-resistance to all commercially available METI-acaricides, a Japanese strain (AKITA) and an English strain (UK-99) of T. urticae were investigated in detail. Larvae of both strains, AKITA and UK-99, showed 1,100- and 480-fold resistance against pyridaben, 870- and 45-fold resistance against fenpyroximate, and 33- and 44-fold resistance against tebufenpyrad, respectively, in a foliar spray application bioassay compared with the susceptible strain GSS. These resistance factors remained stable even when maintained in the laboratory without further selection. Furthermore, strain AKITA showed cross-resistance to dicofol. The METI resistant strains AKITA and UK-99 showed 2.4- and 1.7-fold enhanced O-ethoxycoumarin O-deethylation (cytochrome P450) activity. Increased oxidative metabolism of the METI-acaricides in the resistant strains could be partially suppressed in vivo by the monooxygenase-inhibitor piperonyl butoxide. Reciprocal crosses of homozygous, diploid females and hemizygous, haploid males of strains GSS (susceptible) and AKITA (resistant) revealed that resistance to pyridaben and fenpyroximate was inherited incompletely dominant with slight differences between maternal and paternal inheritance. This is the first attempt to mechanistically describe METI-acaricide resistance in T. urticae. The implications for resistance management strategies are discussed. PMID:11777067

  9. Laboratory evaluation of verbutin as a synergist of acaricides against larvae of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synergistic effects of verbutin, a member of aryl alkynyl derivatives, to three commonly used acaricides were evaluated with the modified Food and Agricultural Organization Larval Packet Test (FAO-LPT) against both susceptible and resistant strains of the southern cattle tick Rhipicephalus (Boophilu...

  10. Acaricidal properties of the essential oil of Melaleuca alternifolia Cheel (tea tree oil) against nymphs of Ixodes ricinus

    Microsoft Academic Search

    A. Iori; D. Grazioli; E. Gentile; G. Marano; G. Salvatore

    2005-01-01

    The aim of the study was to examine the acaricidal effect of essential oil of Melaleuca alternifolia (tea tree oil, TTO) at different doses (4, 6, 8 and 10?l) and for different exposure times (30, 60, 90 and 120min) on nymphs of Ixodes ricinus. A dose of 8?l TTO was lethal for more than 70% of ticks when inhaled and

  11. Efficacy of pheromone-acaricide-impregnated tail-tag decoys for controlling the bont tick,Amblyomma hebraeum (Acari: Ixodidae), on cattle in Zimbabwe

    Microsoft Academic Search

    R. A. I. Norval; Daniel E. Sonenshine; Sandra A. Allan; Michael J. Burridge

    1996-01-01

    A large-scale field test using pheromone-acaricide-impregnated plastic tail-tag decoys demonstrated excellent efficacy of these devices for control of the bont tick,Amblyomma hebraeum, on cattle in Zimbabwe. The tail tags were impregnated with a mixture containingo-nitrophenol, methyl salicylate, 2,6-dichlorophenol and phenylacetaldehyde and one of three different acaricides (cyfluthrin, flumethrin or alphacypermethrin).o-Nitrophenol and methyl salicylate are components of theA. hebraeum attraction-aggregation-attachment pheromone,

  12. Study of acaricide stability in honey. Characterization of amitraz degradation products in honey and beeswax.

    PubMed

    Korta, E; Bakkali, A; Berrueta, L A; Gallo, B; Vicente, F; Kilchenmann, V; Bogdanov, S

    2001-12-01

    A study on the possible degradation of amitraz, bromopropylate, coumaphos, chlordimeform, cymiazole, flumethrin, and tau-fluvalinate during the storage of honey was carried out by HPLC. Except amitraz, the other acaricides are stable in this medium for at least 9 months. Degradation studies of amitraz in honey and beeswax were carried out; the degradation products detected in both matrices were 2,4-dimethylphenylformamide (DMF) and N-(2,4-dimethylphenyl)-N'-methylformamidine (DPMF). The reaction rate constants and the half-lives of the amitraz degradation in honey and wax were calculated. Amitraz was nearly completely degraded within 1 day in beeswax and within 10 days in honey. When amitraz-spiked combs are recycled into new beeswax, DMF was found to be the principal degradation product left in pure wax. PMID:11743771

  13. Acaricidal effect of herbal extracts against cattle tick Rhipicephalus (Boophilus) microplus using in vitro studies.

    PubMed

    Shyma, K P; Gupta, J P; Ghosh, S; Patel, K K; Singh, Veer

    2014-05-01

    The crude methanolic extract of Datura stramonium, Azadirachta indica, and Calotropis procera leaves, Allium sativum (AS) cloves, and Carica papaya (CP) seeds collected from Banaskanta, Gujarat (India) was tested for its acaricidal properties against Rhipicephalus (Boophilus) microplus. The percent adult mortality within 15 days, reproductive index, percentage inhibition of oviposition, hatching of laid ova, and percentage larval mortality were studied at concentrations of 12.5, 25, 50, and 100 mg/ml. At the highest concentration (100 mg/ml), the adult tick mortality was 66.67, 73.33, 80.00, and 93.33% for C. procera, D. stramonium, A. sativum, and C. papaya extracts, respectively, and it was statistically significant (P?acaricidal properties and could be a potential component of alternative R. (B.) microplus tick control strategy. PMID:24633906

  14. Acaricidal properties of the formulations based on essential oils from Cymbopogon winterianus and Syzygium aromaticum plants.

    PubMed

    de Mello, Valéria; Prata, Márcia Cristina de Azevedo; da Silva, Márcio Roberto; Daemon, Erik; da Silva, Luciane Santos; Guimarães, Flávia del Gaudio; de Mendonça, Alessandra Esther; Folly, Evelize; Vilela, Fernanda Maria Pinto; do Amaral, Lilian Henriques; Cabral, Lucio Mendes; do Amaral, Maria da Penha Henriques

    2014-12-01

    The cattle tick, Rhipicephalus (Boophilus) microplus, has caused serious harm to livestock raising in Brazil, considering the costs of controlling it, loss of revenue due to smaller production of milk and meat, and damage to leather, in addition to transmitting diseases. The use of medicinal plants is considered an alternative to the recurring resistance to chemicals. Due to the need for efficient alternatives with less environmental impact, this study aimed to develop contact formulations with essential oils from the Java citronella (Cymbopogon winterianus) and clove (Syzygium aromaticum) plants and to assess in vitro the effects in different stages of the tick cycle. In the present study, concentrations from 0.5-15.0% of the essential oils incorporated in the formulations were used. The ticks from different geographical areas were treated with those formulations, and their effects on the production levels of eggs, on the larvae hatching, and their efficiency on ticks were assessed. The obtained results were compared with other commercial acaricidal products. After the 20th day of treatment, the formulations with citronella essential oil had 2.09-55.51% efficiency, depending on the concentration of the oil incorporated. The efficiency of the treatment with formulations containing clove essential oil was higher, from 92.47-100%. The results showed the acaricidal effects of the formulations tested when compared to commercial chemical products. In vivo studies should be performed in order to assess the efficiency of those formulations in the fields, aiming to use these products as an alternative for controlling cattle ticks. PMID:25199555

  15. Acaricidal constituents isolated from Sinapis alba L. seeds and structure-activity relationships.

    PubMed

    Lim, Jeong-Hyeon; Kim, Hyung-Wook; Jeon, Ju-Hyun; Lee, Hoi-Seon

    2008-11-12

    Allyl isothiocyanate (AITC) and phenethyl isothiocyanate (PEITC) were isolated from Sinapis alba L. seeds and their effects against Dermatophagoides farinae and D. pteronyssinus were evaluated using the impregnated fabric disk method. The LD 50 values of their compounds and derivatives were then compared with those of a commercial acaricide, benzyl benzoate. On the basis of the LD 50 values against D. farinae, PEITC (0.21 microg/cm(2)) was the most toxic, followed by benzyl isothiocyanate (0.55 microg/cm(2)), phenyl isothiocyanate (1.09 microg/cm(2)), butyl isothiocyanate (1.24 microg/cm(2)), and AITC (1.36 microg/cm(2)); acetyl isothiocyanate (195.01 microg/cm(2)) was the least toxic. In addition, the acaricidal effects of AITC and PEITC against D. farinae were 7.4- and 47.8-fold greater than those of benzyl benzoate, respectively. Against D. pteronyssinus, PEITC was the most toxic (0.19 microg/cm(2)), followed by benzyl isothiocyanate (0.77 microg/cm(2)), phenyl isothiocyanate (1.37 microg/cm(2)), butyl isothiocyanate (1.50 microg/cm(2)), and AITC (2.88 microg/cm(2)); acetyl isothiocyanate (168.82 microg/cm(2)) was the least toxic. AITC and PEITC were 3.3- and 50.4-fold more active than benzyl benzoate against D. pteronyssinus, respectively. Taken together, these findings indicate that AITC, PEITC, and partial derivatives may be useful as preventive agents against dust mites. In addition, these results indicate that structure-activity is related to the aromatic structure, the number of carbon atoms, and the compounds hydrophobicity. PMID:18844359

  16. Acaricidal activity of essential oils from five endemic conifers of New Caledonia on the cattle tick Rhipicephalus (Boophilus) microplus.

    PubMed

    Lebouvier, Nicolas; Hue, Thomas; Hnawia, Edouard; Lesaffre, Leïla; Menut, Chantal; Nour, Mohammed

    2013-04-01

    The aim of the present study was to demonstrate acaricidal activity on the cattle tick Rhipicephalus (Boophilus) microplus of essential oils from endemic conifers of New Caledonia in the context of the development of natural alternatives. Acaricidal activity of essential oils extracted from resin and heartwood of five endemic conifers of New Caledonia (Araucaria columnaris, Agathis moorei, Agathis ovata, Callitris sulcata, and Neocallitropsis pancheri) was evaluated on 14- to 21-day-old Rhipicephalus microplus tick larvae using the Larval Packal Test bioassay. A first screening with 5% dilute solution was carried out and the oils with 100% of mortality at this rate were diluted until no activity was shown. The heartwood oils of the two Cupressaceae were the most active with LC50 value of 0.65% for C. sulcata and 0.55% for N. pancheri while resin oil of A. columnaris (LC50=1.62%) was the most active of the Araucariaceae family. Negative control (ethanol) was not toxic to the larvae. The chemical composition of essential oil from resin of A. columnaris was analyzed by gas chromatography-mass spectrometry. The essential oil was characterized by high level of sesquiterpene hydrocarbons and oxygenated sesquiterpenes and was composed mainly of aromadendrene (23.1%) and bicyclogermacrene (16.0%). In order to compare different plant resources in a sustainable program of natural acaricide, an "essential oil efficiency EOE" can be measured as the ratio between the yield of extraction and LC50 value. This study shows that A. columnaris (EOE=2.36) and N. pancheri (EOE=3.51) could provide valuable and effective natural acaricides for control of the cattle tick R. microplus. PMID:23371495

  17. Acaricidal activity of fennel seed oils and their main components against Tyrophagus putrescentiae, a stored-food mite

    Microsoft Academic Search

    Chi-Hoon Lee; Bo-Kyung Sung; Hoi-Seon Lee

    2006-01-01

    The acaricidal activities of components derived from Foeniculum vulgare (fennel) seed oils against Tyrophagus putrescentiae adults were examined using direct contact application and compared with those of the compounds benzyl benzoate, dibutyl phthalate and N,N-diethyl-m-toluamide. The biologically active constituent of the F. vulgare seeds was characterized as (+)-carvone by spectroscopic analyses. On the basis of LD50 values, the compound most

  18. Acaricidal activities of paeonol and benzoic acid from Paeonia suffruticosa root bark and monoterpenoids against Tyrophagus putrescentiae (Acari: Acaridae).

    PubMed

    Tak, Jun-Hyung; Kim, Hyun-Kyung; Lee, Seung-Hwan; Ahn, Young-Joon

    2006-06-01

    The acaricidal activities of paeonol (2'-hydroxy-4'-methoxyacetophenone) and benzoic acid identified in the root bark of tree peony, Paeonia suffruticosa Andrews, against copra mite, Tyrophagus putrescentiae (Schrank), adults were examined using direct contact and vapour phase toxicity bioassays and compared with those of cinnamyl acetate, cinnamyl alcohol and 37 monoterpenoids as well as the acaricides benzyl benzoate, dibutyl phthalate and N,N-diethyl-m-toluamide (DEET). Based on LD(50) values in fabric piece contact toxicity bioassays, the acaricidal activities of benzoic acid (4.80 microg cm(-2)) and paeonol (5.29 microg cm(-2)) were comparable to that of benzyl benzoate (4.46 microg cm(-2)) but more pronounced than those of DEET (30.03 microg cm(-2)) and dibutyl phthalate (25.23 microg cm(-2)). In vapour phase toxicity bioassays, paeonol and benzoic acid were much more effective in closed containers than in open ones, indicating that the effects of these compounds were largely due to action in the vapour phase. As judged by 24 h LD(50) values, (1S)-(-)-verbenone (7.42 mg per disc) was the most toxic fumigant, followed by (1S)-(-)-camphor, (S)-(+)-carvone, (R)-(-)-linalool and (+/-)-camphor (10.45-18.18 mg). Potent fumigant toxicity was also observed with paeonol, (2S,5R)-(-)-menthone, (+/-)-citronellal, benzoic acid, (1S,4R)-(-)-alpha-thujone and (R)-(+)-pulegone (25.10-34.63 mg). Neither benzyl benzoate, DEET nor dibutyl phthalate caused fumigant toxicity. Paeonia root bark-derived materials, particularly paeonol and benzoic acid, as well as the monoterpenoids described, merit further study as potential acaricides or as leads for the control of T. putrescentiae. PMID:16602084

  19. Acaricidal activity of the essential oil from Tetradenia riparia (Lamiaceae) on the cattle tick Rhipicephalus ( Boophilus) microplus (Acari; Ixodidae)

    Microsoft Academic Search

    Zilda Cristiani Gazim; Izabel Galhardo Demarchi; Maria Valdrinez Campana Lonardoni; Ana Carolina L. Amorim; Ana Maria C. Hovell; Claudia Moraes Rezende; Gilberto Alves Ferreira; Edson Luiz de Lima; Fábio Antunes de Cosmo; Diogenes Aparício Garcia Cortez

    2011-01-01

    Tetradenia riparia (Lamiaceae) is a well-known herbal medicine with a variety of useful properties, including its acaricidal effect. This experiment was carried out to study the bioacaricidal activity of T. riparia essential oil (EO) against engorged females of Rhipicephalus (Boophilus) microplus (Acari; Ixodidae). For this purpose, nine serial concentrations (12.50%, 6.25%, 3.75%, 1.80%, 0.90%, 0.45%, 0.22%, 0.11%, and 0.056% w\\/v)

  20. Regulation of Coronafacoyl Phytotoxin Production by the PAS-LuxR Family Regulator CfaR in the Common Scab Pathogen Streptomyces scabies

    PubMed Central

    Cheng, Zhenlong; Bown, Luke; Tahlan, Kapil; Bignell, Dawn R. D.

    2015-01-01

    Potato common scab is an economically important crop disease that is characterized by the formation of superficial, raised or pitted lesions on the potato tuber surface. The most widely distributed causative agent of the disease is Streptomyces scabies, which produces the phytotoxic secondary metabolite thaxtomin A that serves as a key virulence factor for the organism. Recently, it was demonstrated that S. scabies can also produce the phytotoxic secondary metabolite coronafacoyl-L-isoleucine (CFA-L-Ile) as well as other related metabolites in minor amounts. The expression of the biosynthetic genes for CFA-L-Ile production is dependent on a PAS-LuxR family transcriptional regulator, CfaR, which is encoded within the phytotoxin biosynthetic gene cluster in S. scabies. In this study, we show that CfaR activates coronafacoyl phytotoxin production by binding to a single site located immediately upstream of the putative -35 hexanucleotide box within the promoter region for the biosynthetic genes. The binding activity of CfaR was shown to require both the LuxR and PAS domains, the latter of which is involved in protein homodimer formation. We also show that CFA-L-Ile production is greatly enhanced in S. scabies by overexpression of both cfaR and a downstream co-transcribed gene, orf1. Our results provide important insight into the regulation of coronafacoyl phytotoxin production, which is thought to contribute to the virulence phenotype of S. scabies. Furthermore, we provide evidence that CfaR is a novel member of the PAS-LuxR family of regulators, members of which are widely distributed among actinomycete bacteria. PMID:25826255

  1. First report of a Rhipicephalus microplus tick population multi-resistant to acaricides and ivermectin in the Mexican tropics.

    PubMed

    Fernández-Salas, A; Rodríguez-Vivas, R I; Alonso-Díaz, M A

    2012-02-10

    We document the presence of a Rhipicephalus microplus tick population resistant to acaricides (organophosphates (OP), synthetic pyrethroids (SP), amitraz) and macrocyclic lactones (ML) (ivermectin). Engorged females of R. microplus were collected from a cattle farm in Veracruz, Mexico, to evaluate acaricide and ivermectin resistance. The modified larval packet test (LPT) was used to detect OP (chlorpiriphos and diazinon) and SP (flumethrin, deltamethrin and cypermethrin) resistance and the larval immersion test (LIT) to detect resistance to amitraz and ivermectin. Both, LPT and LIT were performed twice at different times with different collected samples. Mortality data with ivermectin were subjected to probit analysis to obtain lethal concentrations and resistance ratios (RR) using an ivermectin-susceptible strain (Deutch) as a reference. The R. microplus population showed resistance to all acaricides tested, with different mortalities at the discriminate dose: chlorpiriphos (1%), diazinon (24.2%), flumethrin (92.8%), deltamethrin (94.2%), cypermethrin (98.0%) and amitraz (1.5%). The studied tick population also showed resistance to ivermectin with a resistance ratio at 99% of 9.58 and 6.52 in the first and second evaluation, respectively. We report for the first time a R. microplus population in Mexico with different levels of resistance to OP, SP, amidines (Am) and ivermectin. The uncontrolled use of these products in the study area may promote the complete failure of tick control within a short period of time. PMID:21824728

  2. Studies on the acaricidal mechanism of the active components from neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi.

    PubMed

    Chen, Zhen-zhen; Deng, Yun-xia; Yin, Zhong-qiong; Wei, Qin; Li, Mei; Jia, Ren-yong; Xu, Jiao; Li, Li; Song, Xu; Liang, Xiao-xia; Shu, Gang; He, Chang-liang; Gu, Xiao-bin; Lv, Cheng; Yin, Lizi

    2014-08-29

    Octadecanoic acid-3,4-tetrahydrofuran diester, isolated from neem (Azadirachta indica) oil, exhibited potent acaricidal activity against Sarcoptes scabiei var. cuniculi. In this paper, the acaricidal mechanism of octadecanoic acid-3,4-tetrahydrofuran diester against Sarcoptes scabiei var. cuniculi was evaluated based on pathologic histology and enzyme activities. The results showed that after compound treatment for 24h at a concentration of 20mg/mL, the lesions of mites were prominent under transmission electron microscopy. The lesions consisted of the lysis of dermis cell membranes and cell nuclear membranes, mitochondrial morphological abnormalities, the drop of spinal disorders, and mitochondrial vacuolization. The activity of superoxide dismutase (SOD), peroxidase (POD), glutathione-s-transferases (GSTs), and Ca(2+)-ATPase of mites significantly changed after treatment with octadecanoic acid-3,4-tetrahydrofuran diester compared with the control group. The activities of SOD, POD, and Ca(2+)-ATPase were significantly suppressed, whereas that of GSTs was activated. These results indicated that the mechanism of the acaricidal activity of octadecanoic acid-3,4-tetrahydrofuran diester was mainly achieved through interference with the energy metabolism of mites, thus resulting in insect death. PMID:24974121

  3. Production of date palm fruits free of acaricides residues by ozone technology as post-harvest treatment.

    PubMed

    Osman, Khaled A

    2015-06-01

    Distilled water and ozonated water as postharvest wash treatments for 15-60 min as dipping times were tested to remove two acaricides namely, dicofol and amitraz from different varieties of date fruits. Recovered amount of the acaricides was extracted using solid phase extraction (SPE) and then analyzed by gas chromatography-mass spectrometry (GC-MS). Dicofol removal percentages in the presence of ozone increased in the order of Nabtet Aly?>?Nabout Seif?>?Khalas?>?Sakay, while amitraz removal increased in the order of Nabtet Aly?>?Nabout Seif?>?Sakay?>?Khalas, respectively, and the percentages of residues on date fruits depended on the dipping time. Kinetic studies revealed that dicofol and amitraz were easily removable from date fruits treated with ozonated water. Ozone-treated date palm fruits were not associated with significant changes in antioxidant capacity, and phenolic and sugar contents. Due to the large amount of dates consumed by Saudi residents, a higher risk of exposure to pesticides, especially in children and other vulnerable individuals may occur and the search for safety methods to remove pesticides with negligible residual deposits has always been preferred. Therefore, the present study validated that ozone technology as wash treatments is safe and promising processes for the removal of acaricides from date fruits surface under domestic conditions to reduce the impact over consumer's health. PMID:26028713

  4. Window contamination on Expose-R

    NASA Astrophysics Data System (ADS)

    Demets, R.; Bertrand, M.; Bolkhovitinov, A.; Bryson, K.; Colas, C.; Cottin, H.; Dettmann, J.; Ehrenfreund, P.; Elsaesser, A.; Jaramillo, E.; Lebert, M.; van Papendrecht, G.; Pereira, C.; Rohr, T.; Saiagh, K.

    2015-01-01

    Expose is a multi-user instrument for astrobiological and astrochemical experiments in space. Installed at the outer surface of the International Space Station, it enables investigators to study the impact of the open space environment on biological and biochemical test samples. Two Expose missions have been completed so far, designated as Expose-E (Rabbow et al. 2012) and Expose-R (Rabbow et al. this issue). One of the space-unique environmental factors offered by Expose is full-spectrum, ultraviolet (UV)-rich electromagnetic radiation from the Sun. This paper describes and analyses how on Expose-R, access of the test samples to Solar radiation degraded during space exposure in an unpredicted way. Several windows in front of the Sun-exposed test samples acquired a brown shade, resulting in a reduced transparency in visible light, UV and vacuum UV (VUV). Post-flight investigations revealed the discolouration to be caused by a homogenous film of cross-linked organic polymers at the inside of the windows. The chemical signature varied per sample carrier. No such films were found on windows from sealed, pressurized compartments, or on windows that had been kept out of the Sun. This suggests that volatile compounds originating from the interior of the Expose facility were cross-linked and photo-fixed by Solar irradiation at the rear side of the windows. The origin of the volatiles was not fully identified; most probably there was a variety of sources involved including the biological test samples, adhesives, plastics and printed circuit boards. The outer surface of the windows (pointing into space) was chemically impacted as well, with a probable effect on the transparency in VUV. The reported analysis of the window contamination on Expose-R is expected to help the interpretation of the scientific results and offers possibilities to mitigate this problem on future missions - in particular Expose-R2, the direct successor of Expose-R.

  5. Resistance to acaricides in Italian strains of Tetranychus urticae: toxicological and enzymatic assays.

    PubMed

    Tirello, Paola; Pozzebon, Alberto; Cassanelli, Stefano; Van Leeuwen, Thomas; Duso, Carlo

    2012-05-01

    Problems with Tetranychus urticae are frequently reported in protected crops in Italy, particularly in roses where many introduced acaricides show a progressive loss of effectiveness. We have conducted bioassays to assess the response of some Italian strains of T. urticae to a number of acaricides. These include compounds that were widespread and frequently used in the past, but also some recently registered compounds. We investigated two T. urticae strains collected from rose growers where control failures were reported (SAN and PSE), together with a strain collected from unsprayed vegetables (BOSA). Adult females of the rose strains (SAN and PSE) were resistant to tebufenpyrad (Resistant Ratio-RR, RR(50) = 48.4 and 163.6) and fenpyroximate (RR(50) = 74.1 and 25.9) when compared to the susceptible BOSA strain. Lethal concentrations for these products were higher than the registered field rate. The PSE strain proved to be highly resistant to abamectin (RR(50) = 1,294.1). Variation in bifenazate susceptibility was detected amongst strains, but LC(90) values of SAN and PSE were still in the range of the registered field rate. In egg bioassays, the SAN and PSE strains exhibited high resistance levels to clofentezine (RR(50) = 66,473 and 170,714), hexythiazox (RR(50) = 70,244 and 159,493) and flufenoxuron (RR(50) = 61.9 and 117.9). But the recently introduced ovi/larvicides etoxazole and spirodiclofen exhibited high activity on all strains. The activity of detoxifying enzymes such as esterases, glutathione-S-transferases (GSTs) and cytochrome P450 monooxygenases (MFOs) was determined in these strains as a preliminary attempt to identify potential resistance mechanisms. Enzymatic assays showed that the rose strains exhibited 2.66 and 1.95-fold increased MFOs activity compared to the susceptible strain. Assays for GSTs revealed that only the SAN strain exhibited a significantly higher activity. In contrast, only the PSE strain showed a significant higher hydrolysis of 1-naphthyl acetate. PMID:22447041

  6. Gene Replacement for the Generation of Designed Novel Avermectin Derivatives with Enhanced Acaricidal and Nematicidal Activities.

    PubMed

    Huang, Jun; Chen, An-Liang; Zhang, Hui; Yu, Zhen; Li, Mei-Hong; Li, Na; Lin, Jia-Tan; Bai, Hua; Wang, Ji-Dong; Zheng, Yu-Guo

    2015-08-15

    Avermectin (AVM) and ivermectin (IVM) are potent pesticides and acaricides which have been widely used during the past 30 years. As insect resistance to AVM and IVM is greatly increasing, alternatives are urgently needed. Here, we report two novel AVM derivatives, tenvermectin A (TVM A) and TVM B, which are considered a potential new generation of agricultural and veterinary drugs. The molecules of the TVMs were designed based on structure and pharmacological property comparisons among AVM, IVM, and milbemycin (MBM). To produce TVMs, a genetically engineered strain, MHJ1011, was constructed from Streptomyces avermitilis G8-17, an AVM industrial strain. In MHJ1011, the native aveA1 gene was seamlessly replaced with milA1 from Streptomyces hygroscopicus. The total titer of the two TVMs produced by MHJ1011 reached 3,400 mg/liter. Insecticidal tests proved that TVM had enhanced activities against Tetranychus cinnabarinus and Bursaphelenchus xylophilus, as desired. This study provides a typical example of exploration for novel active compounds through a new method of polyketide synthase (PKS) reassembly for gene replacement. The results of the insecticidal tests may be of use in elucidating the structure-activity relationship of AVMs and MBMs. PMID:26025902

  7. Acaricidal activity of Cymbopogon citratus and Azadirachta indica against house dust mites

    PubMed Central

    Hanifah, Azima Laili; Awang, Siti Hazar; Ming, Ho Tze; Abidin, Suhaili Zainal; Omar, Maizatul Hashima

    2011-01-01

    Objective To examine the acaricidal effects of the essential oil of Cymbopogon citratus leaf extract (lemongrass) and ethanolic Azadirachta indica leaf extract (neem) against house dust mites Dermatophagoides farinae (D. farinae) and Dermatophagoides pteronyssinus (D. pteronyssinus). Methods Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations (50.00%, 25.00%, 12.50%, 6.25% and 3.13%) and exposure times (24hrs, 48hrs, 72hrs and 96 hrs). All treatments were replicated 7 times, and the experiment repeated once. The topical and contact activities of the two herbs were investigated. Results Mortalities from lemongrass extract were higher than neem for both topical and contact activities. At 50 % concentration, both 24 hrs topical and contact exposures to lemongrass resulted in more than 91% mortalities for both species of mites. At the same concentration and exposure time, neem resulted in topical mortalities of 40.3% and 15.7% against D. pteronyssinus and D. farinae respectively; contact mortalities were 8.0% and 8.9% against the 2 mites, respectively. There was no difference in topical mortalities of D. pteronyssinus from exposure to concentrations of lemongrass and neem up to 12.50%; lemongrass was more effective than neem at the higher concentrations. Conclusions Generally, topical mortalities of D. farinae due to lemongrass are higher than that due to neem. Contact mortalities of lemongrass are always higher that neem against both species of mites. PMID:23569794

  8. EXPOSE-R cosmic radiation time profile

    NASA Astrophysics Data System (ADS)

    Dachev, Tsvetan; Horneck, Gerda; Häder, Donat-Peter; Schuster, Martin

    2015-01-01

    The aim of the paper is to present the time profile of cosmic radiation exposure obtained by the radiation risks radiometer-dosimeter (R3DR) during the ESA exposition facility for EXPOSE-R mission (EXPOSE-R) in the EXPOSE-R facility outside the Russian Zvezda module of the International Space Station (ISS). Another aim is to make the obtained results available to other EXPOSE-R teams for use in their data analysis. R3DR is a low mass and small dimensions automated device, which measures solar radiation in four channels and in addition cosmic ionizing radiation. The main results of cosmic ionizing radiation measurements are: three different radiation sources were detected and quantified: galactic cosmic rays (GCR), energetic protons from the inner radiation belt (IRB) in the region of the South Atlantic anomaly and energetic electrons from the outer radiation belt (ORB). The highest daily averaged absorbed dose rate of 506 ?Gy day-1 came from IRB protons; GCR delivered much smaller daily absorbed dose rates of 81.4 ?Gy day-1 on average, and ORB source delivered on average a dose rate of 89 ?Gy day-1. The IRB and ORB daily averaged absorbed dose rates were higher than those observed during the ESA exposition facility for EXPOSE-E mission (EXPOSE-E), whereas the GCR rate was smaller than that measured during the EXPOSE-E mission. The reason for this difference is much less surrounding constructions shielding of the R3DR instrument in comparison with the R3DE instrument.

  9. Acaricide toxicity and resistance in larvae of different strains of Tetranychus urticae and Panonychus ulmi (Acari: Tetranychidae).

    PubMed

    Nauen, R; Stumpf, N; Elbert, A; Zebitz, C P; Kraus, W

    2001-03-01

    The toxicities of eight structurally different acaricidal compounds to six-legged larvae (first motile stage) of three laboratory strains of the two-spotted spider mite, Tetranychus uritcae, and the European red mite, Panonychus ulmi, were evaluated following spray application. The larvae of five field-derived strains of T urticae originating from France, Italy, Brazil, California and Florida were also tested for their susceptibilities to discriminating concentrations of several acaricides resulting in 95% mortality when applied to the organophosphate-resistant laboratory reference strain WI. The spray bioassay used was robust and gave repeatable results with a wide range of acaricidal compounds, irrespective of their mode of action (ovo-larvicides or primarily acting on motile life stages). Compounds tested were abamectin, azocyclotin, chlorpyrifos, clofentezine, deltamethrin, fenpyroximate, hexythiazox and pyridaben. Larvae of one of the laboratory strains of T urticae, AK, originally collected in Japan in 1996 and maintained without further selection pressure, exhibited 2000- and > 4000-fold resistance to the mitochondrial electron transport inhibitors pyridaben and fenpyroximate, respectively. Another strain of T urticae, AU, obtained from Australia and maintained in the laboratory under selection with hexythiazox and clofentezine since 1987 showed > 770- and > 1000-fold resistance to clofentezine and hexythiazox, respectively. The same resistance pattern was observed against larvae of a laboratory strain of P ulmi, CE, also selected with hexythiazox. Larvae of one of the field-derived strains of T urticae, BR, showed a lower susceptibility to a number of compounds, whilst the others were susceptible to all compounds except the organophosphates. PMID:11455655

  10. Efficiency and cost of strategic use of acaricide for tick control in N'Dama cattle in The Gambia.

    PubMed

    Mattioli, R C; Jaitner, J; Bah, M

    1999-02-01

    The efficiency of strategic and strategic/selective applications of flumethrin spray formulation for controlling ticks were assessed, respectively, in two groups of fourteen N'Dama cattle (Group S and Group S/S) by comparison of the number of feeding ticks with thirteen untreated N'Dama cattle (Group U) over a period of 11 months (June 1996 to April 1997). During the expected peak of tick abundance, acaricide was applied fortnightly on the whole body in animals in Group S and only on the most infested body areas in cattle in Group S/S. Weight changes and skin lesions, directly associated with tick attachment, were recorded in cattle in the three groups. The costs of the two tick control schemes were estimated. Maximum level of ticks, all species together, feeding on cattle was observed in the rainy season. Both in Group S/S and Group S, cattle carried a lower (P < 0.001) number of feeding ticks than animals in Group U over the whole study period. Percentage of tick control, over the entire period of tick investigation, was satisfactory in both acaricide-treated groups, reaching 61.2 and 75.2% in Groups S/S and S, respectively. However, the proportion of control varied according to tick species or genus. Significantly lower prevalence of skin lesions was observed on the ano-genital and udder region in cattle in Group S/S (P < 0.05) and Group S (P < 0.01) in comparison with cattle in Group U. Mean amount of acaricide solution used and relative estimated cost of treatment in cattle in Group S/S were, respectively, 25- and 14-fold lower than those in cattle in Group S. At the end of the study, animals in Groups S/S and S were, respectively, 7.2 and 15.9 kg heavier than animals in Group U. The difference was statistically significant (P < 0.02) only between Groups S and U. However, the efficiency, low cost and derived benefits of the strategic/selective acaricide application scheme indicated that it might be the most cost effective. PMID:10194747

  11. Footbath acaricide treatment to control cattle infestation by the tick Amblyomma variegatum.

    PubMed

    Stachurski, F; Lancelot, R

    2006-12-01

    Previous studies have shown that about 90% of adult Amblyomma variegatum Fabricius (Acari: Ixodidae) picked up daily by grazing cattle are still attached to the interdigital areas in the evening, when the animals return from pasture. It was therefore postulated that a targeted treatment, designed to kill the ticks attached to the feet, would limit infestation of the predilection sites. Footbaths filled with various pyrethroid formulations were used over 3 years, at the beginning of the rainy season (from mid-May to the end of July), to assess the efficacy of such a control method. It proved efficient in preventing the ticks from attaching to the predilection sites. Although five to 12 A. variegatum adults attached to each treated animal daily, and although the tick burden of the predilection sites of control cattle increased each day by four to 10 ticks, the average infestation of the predilection sites of treated cattle that were initially highly infested (over 100 ticks/animal) continuously decreased to reach a level of about 10-30 ticks/animal after 6-8 weeks of treatment. In herds with a lower initial tick burden (40-70 ticks/animal) this level was obtained within 2-3 weeks and the mean infestation subsequently remained consistently low. Footbath treatment carried out every other day during the adult peak infestation period should therefore greatly limit losses due to ticks. This method was appreciated by traditional livestock farmers, essentially because it is not time-consuming and because it requires only c. 200 mL aqueous formulation per animal at each passage. The cost of the acaricide needed to treat one animal during the peak infestation period was assessed at c. euro 0.20. This control method might also have an impact on some species of tsetse flies and mosquitoes, thereby contributing to trypanosomiasis and malaria control. PMID:17199752

  12. Tick control practices in Burkina Faso and acaricide resistance survey in Rhipicephalus (Boophilus) geigyi (Acari: Ixodidae).

    PubMed

    Adakal, Hassane; Stachurski, Frédéric; Chevillon, Christine

    2013-04-01

    Traditional systems account for 95 % of the livestock produced in Burkina Faso. Tick infestation hampers livestock productivity in this area. However, little information exists on tick-control practices used by livestock farmers. We interviewed 60 stockbreeders working in traditional farming systems to obtain the first data on tick-control practices. Sixteen farmers (27 %) did not use conventional practices: seven removed ticks by hand or plastered cattle with dung or engine oil; nine farmers treated cattle with crop pesticides. Forty-four farmers (73 %) used mainly synthetic pyrethroids (SP; either alphacypermethrin or deltamethrin in 20 and 18 farms, respectively) and occasionally amitraz (N = 6). Intervals between treatments varied significantly depending on the chemical used: most farmers using crop pesticides (100 %), amitraz (100 %) or alphacypermethrin (80 %) adjusted tick-control to tick-burden, whereas farmers using deltamethrin tended more to follow a tick-control schedule. Perception of tick-control effectiveness significantly varied among practices: tick-control failures were more frequently reported by farmers using alphacypermethrin (55 %) than by those using either other conventional acaricides (17 %) or crop pesticides (0 %). We investigated whether this could indicate actual development of SP-resistance in cattle ticks. First, using the larval packet test technique, we confirmed that the computation of LC50 and LC90 was repeatable and remained stable across generations of the Rhipicephalus (Boophilus) geigyi Houndé laboratory strain. We then collected from the field fully-engorged female R. geigyi to evaluate the SP-resistance relative to the Houndé reference strain. We did not detect any case of SP-resistance in the field-derived R. geigyi ticks. PMID:22968469

  13. Biofunctional constituent isolated from Citrullus colocynthis fruits and structure-activity relationships of its analogues show acaricidal and insecticidal efficacy.

    PubMed

    Jeon, Ju-Hyun; Lee, Hoi-Seon

    2014-08-27

    The acaricidal and insecticidal potential of the active constituent isolated from Citrullus colocynthis fruits and its structurally related analogues was evaluated by performing leaf disk, contact toxicity, and fumigant toxicity bioassays against Tetranychus urticae, Sitophilus oryzae, and Sitophilus zeamais adults. The active constituent of C. colocynthis fruits was isolated by chromatographic techniques and was identified as 4-methylquinoline on the basis of spectroscopic analyses. To investigate the structure-activity relationships, 4-methylquinoline and its structural analogues were tested against mites and two insect pests. On the basis of the LC50 values, 7,8-benzoquinoline was the most effective against T. urticae. Quinoline, 8-hydroxyquinoline, 2-methylquinoline, 4-methylquinoline, 6-methylquinoline, 8-methylquinoline, and 7,8-benzoquinoline showed high insecticidal activities against S. oryzae and S. zeamais regardless of the application method. These results indicate that introduction of a functional group into the quinoline skeleton and changing the position of the group have an important influence on the acaricidal and insecticidal activities. Furthermore, 4-methylquinoline isolated from C. colocynthis fruits, along with its structural analogues, could be effective natural pesticides for managing spider mites and stored grain weevils. PMID:25110971

  14. Acaricidal activity of ethanolic extract from aerial parts of Tagetes patula L. (Asteraceae) against larvae and engorged adult females of Rhipicephalus sanguineus (Latreille, 1806)

    PubMed Central

    2012-01-01

    Background The tick Rhipicephalus sanguineus is the species with the largest worldwide distribution and is proven to be involved in the transmission of pathogens such as Babesia canis, Ehrlichia canis, Coxiella burnetii, Rickettsia ricketsii, Rickettsia conorii, among others. Studies have demonstrated acquisition of resistance to some of the active principles used in commercial formulations of acaricides. Tagetes patula (Asteraceae) is a plant with highlighted economic and commercial importance due to the production of secondary metabolites with insecticide and acaricide potential, mainly flavonoids, thiophenes and terpenes. Methods The in vitro acaricide action of the ethanolic 70% extract from aerial parts of T. patula, obtained by percolation, was evaluated against larvae and engorged adult females of Rhipicephalus sanguineus by immersion test for 5?minutes. The chemical characterization of this extract was done by liquid chromatography coupled with mass spectrometry (LC-MS), using direct injection of sample. Results Despite T. patula not proving lethal to adults in any of the concentrations tested, at 50.0?mg/mL oviposition rate decreased by 21.5% and eliminated 99.78% of the larvae. Also it was determined that the best results were obtained with 5?minutes of immersion. From the chromatographic analysis twelve O-glycosylated flavonoids were identified. Conclusions This is the first report on the acaricidal activity of T. patula extract against Rh. sanguineus. If we consider the application of the product in the environment, we could completely eliminate the larval stage of development of the ixodid Rh. sanguineus. PMID:23244493

  15. Acaricidal activity of extracts of neem ( Azadirachta indica) oil against the larvae of the rabbit mite Sarcoptes scabiei var. cuniculi in vitro

    Microsoft Academic Search

    Yong-Hua Du; Ren-Yong Jia; Zhong-Qiong Yin; Zhong-Hui Pu; Jiao Chen; Fan Yang; Yu-Qun Zhang; Yang Lu

    2008-01-01

    The acaricidal activity of the petroleum ether extract, the chloroform extract and the acetic ether extract of neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi larvae was tested in vitro. A complementary log–log (CLL) model was used to analyze the data of the toxicity tests. The results showed that at all test time points, the petroleum ether extract demonstrated

  16. Acaricidal effects of herb essential oils against Dermatophagoides farinae and D. pteronyssinus (Acari: Pyroglyphidae) and qualitative analysis of a herb Mentha pulegium (pennyroyal)

    PubMed Central

    Rim, In-Sook

    2006-01-01

    This experiment was undertaken to screen the acaricidal effects of herb essential oils (pennyroyal, ylang ylang, citronella, lemon grass, tea tree, and rosemary) at different doses (0.1, 0.05, 0.025, 0.0125, and 0.00625 µl/cm2) and exposure times (5, 10, 20, 20, 30 and 60 min) on house dust mites Dermatophgoides farinae and D. pteronyssinus. The most effective acaricidal components of pennyroyal (Mentha pulegium) were analyzed using a gas chromatography-mass spectrometer (GC-MS). Of these essential oils, the most effective was pennyroyal, which is composed essentially of pulegone (> 99%), at a dose of 0.025 µl/cm2 which at an exposure time of 5 min killed more than 98% of house dust mites. In the pennyroyal fumigation test, the closed method was more effective than the open method and maximum acaricidal effect was 100% at 0.025 µl/cm2, 60 min. The results show that herb essential oils, in particular, pennyroyal was proved to have potent acaricidal activity. PMID:16809961

  17. In vitro assessment of the acaricidal activity of computer-selected analogues of carvacrol and salicylic acid on Rhipicephalus (Boophilus) microplus.

    PubMed

    Concepción, Ramírez L; Froylán, Ibarra V; Herminia I, Pérez M; Norberto, Manjarrez A; Héctor J, Salgado Z; Yeniel, González C

    2013-10-01

    Rhipicephalus (Boophilus) microplus is a tick that causes huge economic losses in cattle. The indiscriminate use of acaricides has generated resistance to most compounds present on the market. This makes further investigation on other potential acaricides necessary, the in silico assay being an alternative to the design of new compounds. In the present study a biosilico assay was performed using TOMOCOMD-CARDD (TOpological MOlecular COMputer Design-Computer-Aided Rational Drug Design) and WEKA (Waikato Environment for Knowledge Analysis) software. Two carvacrol and four salicylic acid derivatives, synthesized by conventional methods and evaluated with the larval packet test on larvae of R. (B.) microplus were selected. All evaluated compounds presented acaricidal activity; however, ethyl 2-methoxybenzoate (91.8 ± 1.7 % mortality) and ethyl 2,5-dihydroxybenzoate (89.1 ± 1.6 % mortality) showed greater activity than salicylic acid. With regard to the carvacrol analogues, carvacrol acetate (67.8 ± 2.1 % mortality) and carvacrol methyl ether (71.7 ± 1.6 % mortality) also showed greater activity than carvacrol (35.9 ± 3.2 % mortality). TOMOCOMD-CARDD and WEKA software were helpful tools in the search for alternative structures with potential acaricidal activity on R. (B.) microplus. PMID:23543288

  18. Incidence and inheritance of resistance to METI-acaricides in European strains of the two-spotted spider mite (Tetranychus urticae) (Acari: Tetranychidae).

    PubMed

    Devine, G J; Barber, M; Denholm, I

    2001-05-01

    A strain of Tetranychus urticae (Koch; Acari: Tetranychidae), collected from hops (Humulus humuli L; Cannabaceae) in England with a short history of tebufenpyrad use, exhibited resistance to four METI (mitochondrial electron transport inhibitor)-acaricides; tebufenpyrad, pyridaben, fenazaquin and fenpyroximate. Resistance factors for these compounds in a microimmersion assay were 46, 346, 168 and 77 respectively, and corresponded to those exhibited by a Japanese METI-acaricide-resistant reference strain. Levels of resistance remained stable without further selection, and selection with tebufenpyrad did not increase them. The UK strain was also resistant (c 6-fold) to bifenthrin. Crosses of homozygous, diploid females with hemizygous, haploid males showed that, in the UK strain, METI-acaricide resistance was paternally and maternally inherited, and was an incompletely dominant trait. Another tebufenpyrad-resistant strain from the UK, originating from a chrysanthemum nursery (Chrysanthemum foeniculaceum Giseke; Asteraceae) was collected eight months later at a site c 210 km distant from the first. These are the first published incidences of METI-acaricide resistance in Europe and implications for the future use of these compounds are discussed. PMID:11374162

  19. The Effect of Patch Size and Persistence of Host Plants on the Development of Acaricide Resistance in the Two-spotted Spider Mite Tetranychus Urticae (Acari: Tetranychidae)

    Microsoft Academic Search

    Kouichi Goka

    1999-01-01

    Spatial and temporal characteristics of host plants can influence the population biology of the herbivores feeding on them. In this study, I examined the effect of variation in host plant characteristics on the development of acaricide resistance in the two-spotted spider mite Tetranychus urticae, a widely distributed agricultural pest. This investigation examined the geographic variation in the degree of resistance

  20. Acaricidal Treatment of White-Tailed Deer to Control Ixodes Scapularis (Acari: Ixodidae) in a New York Lyme Disease-Endemic Community

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The 4-Poster device for the topical treatment of white-tailed deer, Odocoileus virginianus (Zimmermann) against ticks using the acaricide amitraz was evaluated in a Lyme borreliosis endemic community in Connecticut. As part of a 5-year project from 1997 to 2002, 21–24 of the 4-Posters were distribut...

  1. Topical Treatment of White-Tailed Deer with an Acaricide for the Control of Ixodes Scapularis (Acari: Ixodidae) in a Connecticut Lyme Borreliosis Hyperendemic Community

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The 4-Poster device for the topical treatment of white-tailed deer, Odocoileus virginianus (Zimmermann), against ticks using the acaricide amitraz, was evaluated in a Lyme borreliosis endemic community in Connecticut. As part of a 5-year project from 1997 to 2002, 21–24 of the 4-Posters were distrib...

  2. Assessment of fungal isolates for development of a myco-acaricide for cattle tick control.

    PubMed

    Polar, Perry; Kairo, Moses T K; Peterkin, Dorothy; Moore, Dave; Pegram, Rupert; John, Sally-Ann

    2005-01-01

    Entomopathogenic fungal isolates of Arachnid origin were assessed for their ability to produce mortality and inhibit egg hatching in Boophilus microplus with the aim of selecting an isolate for development into a myco-acaricide for control of cattle ticks. The ability of the most promising isolate to target developmental stages of more than one tick species and the optimum concentration of fungal inoculum to be used for future studies were determined. Metarhizium anisopliae was the most pathogenic of the three fungal species tested on B. microplus, producing shorter average survival times (ASTs) for engorged adults (AST = 5.2 +/- 0.1 days) and larvae (AST = 9.3 +/- 0.4 days), and a longer average hatching times (AHT; AHT = 19.8 +/- 0.5 days) in comparison to Simplicillium lamellicola and Paecilomyces farinosus. In comparative studies on two tick species with similar life cycles, M. anisopliae produced a shorter AST in engorged adult B. microplus (AST = 8.8 +/- 0.3 days) than Rhipicephalus sanguineus (AST = 10.3 +/- 0.3 days). M. anisopliae was pathogenic to larvae of B. microplus (AST = 7.7 +/- 0.4 days), however, had no effect on larvae of R. sanguineus (AST = 14.6 +/- 0.3 days) as the AST of this treatment was similar to its untreated control (AST = 14.1 +/- 0.4 days). M. anisopliae lengthened the AHTs in both B. microplus (AHT = 16.4 +/- 0.3 days) and R. sanguineus (AHT = 16.7 +/- 0.3 days) in comparison to the controls. The ASTs of engorged adult B. microplus treated with M. anisopliae shortened as the concentration was increased from 1 x 10(7) to 5 x 10(8) conidia/ mL. A further increase in concentration, 1 x 10(9) conidia/mL (AST = 10.2 +/- 0.4 days) did not shorten or lengthen the AST in comparison to 5 x 10(8) conidia/mL (AST = 9.4 +/- 0.3 days). PMID:16187897

  3. Purification and characterization of a novel extracellular esterase from pathogenic Streptomyces scabies that is inducible by zinc.

    PubMed Central

    McQueen, D A; Schottel, J L

    1987-01-01

    Native polyacrylamide gels of extracellular proteins produced by several Streptomyces isolates grown with suberin were assayed in situ for esterase activity. Two pathogenic isolates of Streptomyces scabies from different geographical regions were found to produce a similar esterase activity that was not produced by nonpathogenic strains. After treatment with EDTA, suberin no longer induced esterase production. Expression was restored when EDTA-treated suberin was supplemented with zinc. The optimal concentration of zinc required for esterase production was 2 microM. This esterase was purified from one of the pathogenic isolates and characterized. The enzyme was 38,000 daltons when determined by gel filtration on Sephadex G-100 and 36,000 daltons when determined by denaturing polyacrylamide gel electrophoresis. The esterase showed maximal activity in sodium phosphate buffer above pH 8.0, was stable to temperatures of up to 60 degrees C, and had an apparent Km of 125 microM p-nitrophenyl butyrate. Images PMID:3571156

  4. Reduced Efficacy of Commercial Acaricides Against Populations of Resistant Cattle Tick Rhipicephalus microplus from Two Municipalities of Antioquia, Colombia

    PubMed Central

    Lopez-Arias, Anderson; Villar-Argaiz, David; Chaparro-Gutierrez, Jenny J; Miller, Robert J; Perez de Leon, Adalberto A

    2014-01-01

    Two distant Antioquian cattle farms where systemic and topical acaricides had previously failed to control infestations by Rhipicephalus (Boophilus) microplus were studied. An initial in vivo study was conducted using single subcutaneous injections with a long-acting formulation of ivermectin (630 ?g/kg). Injections were made at 3-month intervals on animals at each farm to evaluate the therapeutic and persistent efficacy of ivermectin against R. microplus. Body tick counts and reproductive parameters of semi- or fully engorged females (?5 mm) were assessed at 10-day intervals, and since no negative control group could be included, values were compared against those for day 0. Although there was an overall reduction of 50%–75% in tick numbers that persisted for 30–40 days, it was not significantly different at one of the farms and not enough to afford protection from severe infestations. The engorgement weight and egg mass weight of ticks from treated animals were significantly lower throughout the 50-day posttreatment period. Egg hatch was not significantly reduced posttreatment and remained at levels of 80%–90%. A random selection of 9 out of 28 commercial formulations of ivermectin sold in Colombia were analyzed by High Performance Liquid Chromatography (HPLC). All were within the expected labeled concentration (±15% deviation) of 1% and 3.15% ivermectin except for one. A popular unregistered injectable widely used in both farms and labeled as “natural pyrethrin”, was found to contain 10.5% ivermectin. An adult immersion test was conducted to evaluate the efficacy of topical acaricides to recommended concentrations of five commercial products and/or their combinations. Efficacy was determined by comparing the reproductive index of each treated group to that of the control group. Cypermethrin (150 ppm) was completely ineffective at both farms. Amitraz (208 ppm) exhibited low and intermediate efficacies of 14% and 56%. The combination of amitraz (100 ppm) and cypermethrin (150 ppm) was less efficacious than the amitraz alone. A generic product based on amitraz + citronella (208 ppm + 10 ppm, respectively) was shown to be less efficacious than the name-brand amitraz product. Products containing the organophosphate chlorpyrifos or trichlorfon exhibited intermediate efficacies of approximately 60% at the Tarso farm. We conclude that at these two locations, there is a high degree of resistance to many of the acaricides available in Colombia and confirm suspicions that ivermectin is no longer able to eliminate tick infestations. PMID:25987840

  5. Acaricidal activity of the essential oil from Tetradenia riparia (Lamiaceae) on the cattle tick Rhipicephalus (Boophilus) microplus (Acari; Ixodidae).

    PubMed

    Gazim, Zilda Cristiani; Demarchi, Izabel Galhardo; Lonardoni, Maria Valdrinez Campana; Amorim, Ana Carolina L; Hovell, Ana Maria C; Rezende, Claudia Moraes; Ferreira, Gilberto Alves; de Lima, Edson Luiz; de Cosmo, Fábio Antunes; Cortez, Diogenes Aparício Garcia

    2011-10-01

    Tetradenia riparia (Lamiaceae) is a well-known herbal medicine with a variety of useful properties, including its acaricidal effect. This experiment was carried out to study the bioacaricidal activity of T. riparia essential oil (EO) against engorged females of Rhipicephalus (Boophilus) microplus (Acari; Ixodidae). For this purpose, nine serial concentrations (12.50%, 6.25%, 3.75%, 1.80%, 0.90%, 0.45%, 0.22%, 0.11%, and 0.056% w/v) of T. riparia were used for the adult immersion test (AIT). For the larval packet test (LPT), we used 14 serial concentrations (100.00%, 50.00%, 25.00%, 12.50%, 6.25%, 3.65%, 1.82%, 0.91%, 0.45%, 0.228%, 0.114%, 0.057%, 0.028%, and 0.014% w/v). The results for AIT showed 100.00% and 2.05% mortality, 19.00 and 90.20% for the total number of eggs, egg-laying inhibition of 0.00% and 90.20%, hatchability inhibition of 0.00% and 70.23%, and product effectiveness of 100.00% and 2.89%, respectively. The AIT indicated that the LC(50) and LC(99.9), calculated using the Probit test, were for mortality (%) 0.534g/mL (0.436-0.632) and 1.552g/mL (1.183-1.92); for total number of eggs were 0.449g/mL (0.339-0.558) and 1.76g/mL (1.27-2.248); and for hatchability inhibition were 0.114g/mL (0.0-0.31) and 2.462g/mL (1.501-3.422), respectively. Larvae between 14 and 21days old were fasted and placed in each envelope. Bioassays were performed at 27°±1°C, RH?80%. Larval mortality was observed 24h after treatment and showed 10.60-100% mortality in the LPT bioassay. The LPT showed that the LC(50) and LC(99.9) were 1.222g/mL (0.655-1.788) and 11.382g/mL (7.84-14.91), respectively. A positive correlation between T. riparia EO concentration and tick control, was observed by the strong acaricidal effects against R. (B.) microplus, and the mortality rate of ticks was dose-dependent. Our results showed that T. riparia is a promising candidate as an acaricide against resistant strains of R. (B.) microplus. PMID:21762693

  6. Sarcoptic mange in captive maras: the first known outbreak and complete recovery with colony-wide acaricide treatment

    PubMed Central

    KIM, Kyoo-Tae; LEE, Seung-Hun; KWAK, Dongmi

    2015-01-01

    Among 16 maras housed as a colony at a zoo, 2 initially showed generalized dermal lesions on the legs, head and abdomen. Approximately 1 month later, following completion of therapy with amitraz, 6 maras in the same colony, including the 2 previously diseased animals, showed dermal lesions with severe alopecia and crusting. Sarcoptic mange was diagnosed on skin scrapings on the basis of morphological criteria. The mites were highly mobile and abundant in all cases, and no other causative agents were detected. Colony-wide treatment with ivermectin and prednisolone was administered weekly for a total of 4 treatments. After therapy was completed in all cohabitants, follow-up scrapings were negative for Sarcoptes scabiei. This report describes the first known outbreak of sarcoptic mange in captive maras and successful treatment with acaricides. PMID:25648673

  7. Sarcoptic mange in captive maras: the first known outbreak and complete recovery with colony-wide acaricide treatment.

    PubMed

    Kim, Kyoo-Tae; Lee, Seung-Hun; Kwak, Dongmi

    2015-06-01

    Among 16 maras housed as a colony at a zoo, 2 initially showed generalized dermal lesions on the legs, head and abdomen. Approximately 1 month later, following completion of therapy with amitraz, 6 maras in the same colony, including the 2 previously diseased animals, showed dermal lesions with severe alopecia and crusting. Sarcoptic mange was diagnosed on skin scrapings on the basis of morphological criteria. The mites were highly mobile and abundant in all cases, and no other causative agents were detected. Colony-wide treatment with ivermectin and prednisolone was administered weekly for a total of 4 treatments. After therapy was completed in all cohabitants, follow-up scrapings were negative for Sarcoptes scabiei. This report describes the first known outbreak of sarcoptic mange in captive maras and successful treatment with acaricides. PMID:25648673

  8. Study of an accelerated solvent extraction procedure for the determination of acaricide residues in honey by high-performance liquid chromatography-diode array detector.

    PubMed

    Korta, E; Bakkali, A; Berrueta, L A; Gallo, B; Vicente, F

    2002-01-01

    An accelerated solvent extraction (ASE) procedure has been optimized for the determination of synthetic acaricides (amitraz, bromopropylate, cymiazole, coumaphos, T-fluvalinate, and flumethrin) and their residues in honey by reversed-phase high-performance liquid chromatography. The effects of experimental variables such as solvent composition, temperature, static extraction time, and solvent flush volume on the ASE efficiency have been studied. The acaricides were extracted by hexane-propanol (1/3, vol/vol) at 95 degrees C and 2.000 psi for 8 min. Recovery values of between 53 and 108% were achieved with the different substances, with coefficients of variation between 2 and 13% and limits of detection from 0.01 to 0.2 microg/g. PMID:11808788

  9. The preparation of neem oil microemulsion ( Azadirachta indica) and the comparison of acaricidal time between neem oil microemulsion and other formulations in vitro

    Microsoft Academic Search

    Jiao Xu; Qiao-Jia Fan; Zhong-Qiong Yin; Xu-Ting Li; Yong-Hua Du; Ren-Yong Jia; Kai-Yu Wang; Cheng Lv; Gang Ye; Yi Geng; Gang Su; Ling Zhao; Ting-Xiu Hu; Fei Shi; Li Zhang; Chang-Long Wu; Cui Tao; Ya-Xue Zhang; Dong-Xia Shi

    2010-01-01

    The preparation of neem oil microemulsion and its acaricidal activity in vitro was developed in this study. In these systems, the mixture of Tween-80 and the sodium dodecyl benzene sulfonate (SDBS) (4:1, by weight) was used as compound surfactant; the mixture of compound surfactant and hexyl alcohol (4:1, by weight) was used as emulsifier system; the mixture of neem oil,

  10. Acaricidal activity of the essential oils from Eucalyptus citriodora and Cymbopogon nardus on larvae of Amblyomma cajennense (Acari: Ixodidae) and Anocentor nitens (Acari: Ixodidae).

    PubMed

    Clemente, Mateus Aparecido; de Oliveira Monteiro, Caio Márcio; Scoralik, Márcio Goldner; Gomes, Fernando Teixeira; de Azevedo Prata, Márcia Cristina; Daemon, Erik

    2010-09-01

    The present study evaluated the acaricidal activity of essential oils from Eucalyptus citriodora and Cymbopogon nardus on non-engorged larvae of Amblyomma cajennense and Anocentor nitens. In order to carry out the study, six groups were formed, each concentration being a treatment (6.25%, 12.5%, 25%, and 50%, respectively) and also with the creation of a control group (distilled water) and a positive control (Deltametrine). For each treatment, approximately 100 larvae of these ticks were placed onto filter papers (2 x 2 cm) impregnated with the concentrations used to test. Next, the envelopes were closed bearing inside the filter paper with measurements of 6 x 6 cm. For each group, six repetitions were performed, and after 24 h live and dead larvae were counted. This procedure was carried out for two essential oils on the two species of ticks. For A. cajennense, the acaricide efficacy of E. citriodora oil was of 10.8%, 35.3%, 34.5%, and 53.1%, whereas the efficacy of C. nardus was of 0.0%, 0.0%, 0.0%, and 61.1% at concentrations of 6.25%, 12.5%, 25.0%, and 50.0%, respectively. In relation to A. nitens, the acaricide efficacy of E. citriodora oil was of 20.1%, 84.5%, 89.2%, and 100.0%, whereas the efficacy of C. nardus was of 0.0%, 90.8%, 100.0%, and 100.0% at concentrations of 6.25%, 12.5%, 25.0%, and 50.0%, respectively. The results indicate that the essential oils tested showed a promising acaricidal activity mainly on A. nitens larvae. PMID:20640444

  11. The development of resistance to organophosphorus compounds by Tetranychus (T.) urticae Koch and laboratory and field toxicological responses of Tetranychus (T.) Cinnabarinus (Boisduval) to some current acaricides 

    E-print Network

    Contreras Galvez, Saul Edgardo

    1971-01-01

    spider mite supple- mentatlon from local methyl parathion treated plots. Mite culture and treatment procedures were conducted as previously described in the preceding pages. A different mite transfer technique was followed in this test. Ten two... 1929 and 1946 rotenone, thiocyanates, cyclohexylamine derivatives, dinitrophenol compounds, naphthalene, and methyl bromide were the most generally used acaricides. Since 1947, organic acari cides and in- secticides have been widely used for mite...

  12. Evaluation of the acaricide effect of thymol, menthol, salicylic acid, and methyl salicylate on Boophilus microplus (Canestrini 1887) (Acari: Ixodidae) larvae

    Microsoft Academic Search

    Adriana Maria da Silveira Novelino; Erik Daemon; Geraldo Luiz Gonçalves Soares

    2007-01-01

    The tick Boophilus microplus is the principal species of ectoparasite that impairs dairy cattle productivity in Brazil. Its control is mainly by using\\u000a synthetic chemical products during its parasitic phase. The purpose of this study is to evaluate the acaricide activity of\\u000a four products of natural origin. Depending on solubility, tests were conducted with solutions in distilled water or emulsified

  13. Acaricidal activity of petroleum ether extract of neem (Azadirachta indica) oil and its four fractions separated by column chromatography against Sarcoptes scabiei var. cuniculi larvae in vitro.

    PubMed

    Deng, Yunxia; Shi, Dongxia; Yin, Zhongqiong; Guo, Jianhong; Jia, Renyong; Xu, Jiao; Song, Xu; Lv, Cheng; Fan, Qiaojia; Liang, Xiaoxia; Shi, Fei; Ye, Gang; Zhang, Wei

    2012-04-01

    The petroleum ether extract of neem oil and its four fractions separated by column chromatography was diluted at different concentrations with liquid paraffin. The acaricidal bioassay was conducted using a dipping method. The results indicated that the median lethal concentration (LC50) of the petroleum ether extract (at the concentration of 500.0ml/l) was 70.9ml/l, 24h after treatment. At concentrations of 500.0, 250.0, 125.0, 62.5 and 31.2ml/l, the median lethal times (LT50) of the petroleum ether extract were 8.7, 8.8, 10.8, 11.5 and 13.1h, respectively. Thin-layer chromatography (TLC) showed that the petroleum ether extract of neem oil separated into four fractions (F1-F4). Acaricidal activity of 68.3% and 100.0% in the F2 and F4 was confirmed. These results suggest that petroleum ether extracts of neem oil and its four fractions possess useful acaricidal activity in vitro. PMID:22349080

  14. Rhipicephalus sanguineus (Acari: Ixodidae) female ticks exposed to castor oil (Ricinus communis): an ultrastructural overview.

    PubMed

    Sampieri, B R; Furquim, K C S; Nunes, P H; Camargo-Mathias, M I

    2013-02-01

    Tick control has been accomplished through the use of synthetic acaricides, which has created resistant individuals, as well as contaminating the environment and nontarget organisms. Substances of plant origin, such as oils and extracts of eucalyptus and neem leaves, have been researched as an alternative to replace the synthetic acaricides. Ricinoleic acid esters from castor oil have recently been shown as a promising alternative in eliminating bacterial contamination during ethanol fermentation, by acting as an effective biocide. The same positive results have been observed when these esters are added to the food given to tick-infested rabbits. This study tested the effect of these substance on the reproductive system of Rhipicephalus sanguineus females, added to rabbit food, more specifically on oogenesis. For this, four groups were established: four control groups (CG1, CG2, CG3, and CG4) and four treatment groups (TG1, TG2, TG3, and TG4) with one rabbit in each (New Zealand White), used as hosts. After full 4 days feeding (semi-engorgement), the females were collected and had their ovaries extracted. In this study, it was observed that R. sanguineus females exposed to esters had their ovaries modified, which was demonstrated through transmission electron microscopy techniques. The addition of ricinoleic esters to the diet of tick-infested rabbits revealed how toxic such substances are for the cytoplasmic organelles of oocytes and pedicel cells. These compounds can change the morphophysiology of germ and somatic cells, consequently influencing their viability and, therefore, confirming that the ricinoleic acid esters from castor oil are a promising substance in the control of R. sanguineus. PMID:23086445

  15. Acaricide and ivermectin resistance in a field population of Rhipicephalus microplus (Acari: Ixodidae) collected from red deer (Cervus elaphus) in the Mexican tropics.

    PubMed

    Rodríguez-Vivas, R I; Miller, R J; Ojeda-Chi, M M; Rosado-Aguilar, J A; Trinidad-Martínez, I C; Pérez de León, A A

    2014-02-24

    In the Neotropics the control of tick infestations in red deer (Cervus elaphus) is achieved primarily through the use of acaricides and macrocyclic lactones. In Mexico, resistance to one or multiple classes of acaricides has been reported in Rhipicephalus microplus infesting cattle, but information on acaricide susceptibility in R. microplus infesting red deer is lacking. In this study we report the level of resistance to different classes of acaricides and ivermectin in R. microplus collected from red deer in the Mexican tropics. Engorged R. microplus females were collected from a red deer farm in Yucatan, Mexico. The larval packet test was used to detect resistance to the organophosphates (OPs) chlorpyrifos and coumaphos, synthetic pyrethroids (SPs) cypermethrin and permethrin, and the phenylpyrazol, fipronil. Resistance to the formamidine amitraz (Am), and ivermectin was ascertained using the larval immersion test. Data were subjected to probit analysis to determine lethal concentrations and resistance ratios to kill 50% (RR50) and 99% (RR99) of the tick population under evaluation in relation to susceptible reference strains. Additionally, allele specific polymerase chain reaction was used to detect the sodium channel F1550I mutation associated with SP resistance in R. microplus. The R. microplus population from red deer in Yucatan showed very high resistance to the two SPs evaluated (RRs>72.2 for cypermethrin; RR for permethrin resistance was so high a dose-response curve was not possible). All individual larvae tested to detect the sodium channel F1550I mutation associated with SP resistance in R. microplus were homozygous. The same tick population showed different levels of resistance to OPs (chlorpyrifos: RR50=1.55, RR99=0.63; coumaphos: RR50=6.8, RR99=5.9), fipronil (RR50=1.8, RR99=0.9), and amitraz (RR50=2.3, RR99=4.4). Resistance to ivermectin was regarded as moderate (RR50=7.1, RR99=5.0). This is the first report of R. microplus ticks collected from red deer in Mexico with different levels of resistance to four acaricide groups and ivermectin. PMID:24365245

  16. Survey of acaricides resistance status of Rhipiciphalus (Boophilus) microplus collected from selected places of Bihar, an eastern state of India.

    PubMed

    Ghosh, Srikant; Kumar, Rinesh; Nagar, Gaurav; Kumar, Sachin; Sharma, Anil Kumar; Srivastava, Aman; Kumar, Suman; Ajith Kumar, K G; Saravanan, B C

    2015-07-01

    Monitoring acaricide resistance in field ticks and use of suitable managemental practices are essential for controlling tick populations infesting animals. In the present study, the acaricide resistance status in Rhipicephalus (Boophilus) microplus ticks infesting cattle and buffaloes of five districts located in the eastern Indian state, Bihar were characterized using three data sets (AIT, Biochemical assays and gene sequences). Adult immersion test (AIT) was adopted using seven field isolates and their resistance factor (RF) was determined. Six isolates (DNP, MUZ, BEG, VSH, DRB and SUL) were found resistant to both deltamethrin and diazinon and except VSH all were resistant to cypermethrin. One isolate (PTN) was susceptible with a RF below 1.5. To understand the possible mode of resistance development, targeted enzymes and gene sequences of the para sodium channel and achetylcholinesterase 2 (AChE2) were analyzed. The esterase, monooxygenase and glutathione-S-transferase (GST) activity of reference susceptible IVRI-I line was determined as 2.47±0.007nmol/min/mg protein, 0.089±0.0016nmol/mg of protein and 0.0439±0.0003nmol/mg/min respectively, which increased significantly in the resistant field isolates. However, except esterases, the fold increase of monooxygenase (1.14-2.27 times) and GST (0.82-1.53 times) activities were not very high. A cytosine (C) to adenine (A) nucleotide substitution (CTC to ATC) at position 190 in domain II S4-5 linker region was detected only in one isolate (SUL) having RF of 34.9 and in the reference deltamethrin resistant line (IVRI-IV). However, the T2134A mutation was not detected in domain IIIS6 transmembrane segment of resistant isolates and also in reference IVRI-IV line despite of varying degree of resistance. The flumethrin specific G215T and the recently identified T170C mutations were also absent in domain II sequences under study. Four novel amino acid substitutions in AChE2 gene of field isolates and in organophosphate (OP) resistant reference IVRI-III line were identified which can possibly have a role in resistance development. PMID:26117183

  17. Determination and surveillance of nine acaricides and one metabolite in honey by liquid chromatography-tandem mass spectrometry.

    PubMed

    Nakajima, Takayuki; Tsuruoka, Yumi; Kanda, Maki; Hayashi, Hiroshi; Hashimoto, Tsuneo; Matsushima, Youko; Yoshikawa, Souichi; Nagano, Chieko; Okutomi, Yuki; Takano, Ichiro

    2015-07-01

    A simple and accurate analytical method for the determination of acaricides in honey was developed and validated in accordance with Japanese validation guidelines. Analytes - amitraz, N-2,4-dimethylphenyl-N-methylformamidine (DMPF), etoxazole, fenpyroximate, fipronil, hexythiazox, propargite, pyridaben and spirodiclofen - were extracted with ethyl acetate under basic conditions and subsequently cleaned up using an InertSep(®) MA-1 polymer-based anion-exchange column. The method was validated by fortified recovery tests at three different concentrations (1, 5 and 10 µg kg(-1)) performed with three samples daily on five different days. The method exhibited recoveries of 77-116% and precision (relative standard deviations - RSDs) of repeatability and within-laboratory reproducibility ranged from 2% to 22% and from 3% to 23%, respectively. The sample solution was successfully cleaned up to enable quantification using external solvent calibration curves. The limits of quantification (LOQs) were estimated to be 1 µg kg(-1) for all analytes. The method was applied to honey samples commercially available in Tokyo, Japan. Analysis of 250 honey samples indicated that amitraz was present in 127 samples, and that its residual concentration was less than 20 µg kg(-1). Propargite was detected in 23 samples at concentrations less than 1 µg kg(-1). PMID:25967980

  18. Acaricidal activity of essential oils from Lippia alba genotypes and its major components carvone, limonene, and citral against Rhipicephalus microplus.

    PubMed

    Peixoto, Magna Galvão; Costa-Júnior, Livio Martins; Blank, Arie Fitzgerald; Lima, Aldilene da Silva; Menezes, Thays Saynara Alves; Santos, Darlisson de Alexandria; Alves, Péricles Barreto; Cavalcanti, Sócrates Cabral de Holanda; Bacci, Leandro; Arrigoni-Blank, Maria de Fátima

    2015-05-30

    The goal of the present study was to evaluate the acaricidal potential of Lippia alba essential oil, citral chemotypes (LA-10 and LA-44 genotypes) and carvone chemotypes (LA-13 and LA-57 genotypes), as well as purified citral and enantiomers of carvone and limonene. Efficacy against Rhipicephalus microplus was assessed by the larval packet and the engorged female immersion tests. Citral chemotypes had greater larvicidal activity than carvone chemotypes, and this was further supported by larvicidal and adulticidal activity of purified citral with LC50 values of 7.0 and 29.8mg/mL, respectively. While purified enantiomers of carvone exhibited greater larvicidal activity than those of limonene, enantioselectivity of limonene was observed with R-(+) displaying significantly higher efficacy (LC50 of 31.2mg/mL) than S-(-) (LC50 of 54.5mg/mL). The essential oils and purified compounds were much less toxic toward engorged adult females, with the exception of citral, and this may be due to limited cuticular penetration. PMID:25837783

  19. The development of resistance to organophosphorus compounds by Tetranychus (T.) urticae Koch and laboratory and field toxicological responses of Tetranychus (T.) Cinnabarinus (Boisduval) to some current acaricides

    E-print Network

    Contreras Galvez, Saul Edgardo

    1971-01-01

    resistant' In view of these facts previously mentioned, research was conducted on two species of spider mites attacking cotton in the area of College Station, T, Th *p l. o d T~th )~T*t h ) tt * K ch d ~r*t h )apt chus) cinnabarinus (Boisduval). Both... of some currently available acaricides for control of thts last species. To accomplish the first objective, spider mj tes were collected by hand from cotton fields and green- houses. They were then successfully mass reared on cotton seedlings grown...

  20. Evaluation of benzaldehyde derivatives from Morinda officinalis as anti-mite agents with dual function as acaricide and mite indicator.

    PubMed

    Yang, Ji-Yeon; Kim, Min-Gi; Park, Jun-Hwan; Hong, Seong-Tshool; Lee, Hoi-Seon

    2014-01-01

    Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by SFTS virus with 12-30% fatality rate. Despite severity of the disease, any medication or treatment for SFTS has not developed yet. One approach to prevent SFTS spreading is to control the arthropod vector carrying SFTS virus. We report that 2-methylbenzaldehyde analogues from M. officinalis have a dual function as acaricide against Dermatophagoides spp. and Haemaphysalis longicornis and indicator (color change) against Dermatophagoides spp. Based on the LD50 values, 2,4,5-trimethylbenzaldehyde (0.21, 0.19, and 0.68 ?g/cm(3)) had the highest fumigant activity against D. farinae, D. pteronyssinus, and H. longicornis, followed by 2,3-dimethylbenzaldehyde (0.46, 0.44, and 0.79 ?g/cm(3)), 2,4-dimethylbenzaldehyde (0.66, 0.59, and 0.95 ?g/cm(3)), 2,5-dimethylbenzaldehyde (0.65, 0.68, and 0.88 ?g/cm(3)), 2-methylbenzaldehyde (0.95, 0.87, and 1.28 ?g/cm(3)), 3-methylbenzaldehyde (0.99, 0.93, and 1.38 ?g/cm(3)), 4-methylbenzaldehyde (1.17, 1.15, and 3.67 ?g/cm(3)), and M. officinalis oil (7.05, 7.00, and 19.70 ?g/cm(3)). Furthermore, color alteration of Dermatophagoides spp. was shown to be induced, from colorless to dark brown, by the treatment of 2,3-dihydroxybenzaldehyde. These finding indicated that 2-methylbenzaldehyde analogues could be developed as functional agent associated with the arthropod vector of SFTS virus and allergen. PMID:25434408

  1. Disease at the wildlife-livestock interface: acaricide use on domestic cattle does not prevent transmission of a tick-borne pathogen with multiple hosts.

    PubMed

    Walker, Josephine G; Klein, Eili Y; Levin, Simon A

    2014-01-31

    Several prominent and economically important diseases of livestock in East Africa are caused by multi-host pathogens that also infect wildlife species, but management strategies are generally livestock focused and models of these diseases tend to ignore the role of wildlife. We investigate the dynamics of a multi-host tick-borne disease in order to assess the efficacy of tick control from an ecological perspective. We examined the efficacy of a widespread measure of tick control and developed a model to explore how changes in the population of ticks due to control measures on cattle impact dynamics of Theileria parva infection in a system with two primary host species, cattle and Cape buffalo (Syncerus caffer). We show that the frequency of acaricide application has a significant impact on the tick population both on the host and in the environment, which can greatly reduce the pathogen load in cattle. We also demonstrate that reducing the tick population through cattle-related control measures is not sufficient to diminish disease transmission in buffalo. Our results suggest that under current control strategies, which target ticks on cattle only, T. parva is likely to remain a significant problem in East Africa, and require the continued use of acaricides, which has significant economic and ecological consequences. PMID:24315187

  2. Use of polymerase chain reaction: Restriction fragment length polymorphism to detect acaricidal resistance to synthetic pyrethroids in Boophilus microplus ticks of South India

    PubMed Central

    Cattavarayane, Mathivathani; Basith, Abdul; Latha, Bhaskaran Ravi

    2013-01-01

    Background: Boophilus microplus is an important ectoparasite of livestock. Apart from transmitting diseases, heavy tick burden can decrease production and damage hides. The synthetic pyrethroids which are advantageous over other acaricides for treatment of this infestation are now losing their efficacy due to development of resistant strains of ticks. Materials and Methods: Boophilus microplus ticks with a previous history of acaricidal treatment especially synthetic pyrethroids (SP) such as cypermethrin, deltamethrin and flumethrin were randomly collected from different pockets of four Southern States of India namely Tamil Nadu, Kerala, Karnataka, Andhra Pradesh, and Puducherry from cattle. Deoxyribonucleic acid extracted from pooled adult B. microplus tick from each State was subjected to polymerase chain reaction-restriction fragment length polymorphism to detect point mutation in carboxyl esterase gene. Results: A product size of 372 bp was obtained for cattle tick samples collected from all over Southern States of India. Conclusions: B. microplus ticks found in Southern part of India are not resistant to commonly used SP. PMID:23961446

  3. Effects of tick control by acaricide self-treatement of white-tailed deer on host-seeking tick infection prevalence and entomologic risk for Ixodes scapularis-borne pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We evaluated the effects of tick control by acaricide self-treatment of white-tailed deer on the infection prevalence and entomologic risk for three I. scapularis-borne bacteria in host-seeking ticks. Ticks were collected from vegetation in areas treated with the ‘4-Poster’ device and from control a...

  4. Strategic applications of long-acting acaricides against Rhipicephalus (Boophilus) microplus in northwestern Argentina, with an analysis of tick distribution among cattle.

    PubMed

    Nava, Santiago; Mangold, Atilio J; Canevari, José T; Guglielmone, Alberto A

    2015-03-15

    Strategic applications of long-acting acaricides for the control of Rhipicephalus (Boophilus) microplus in northwestern Argentina were evaluated for one year. In addition, tick distribution among cattle was analyzed to evaluate if partial selective treatment or culling the small proportion of most heavily infested animals were feasible options to control R. (B.) microplus. Two different treatments schemes based on two applications of fluazuron and one application of 3.15% ivermectin were performed. Treatments were made in late winter and spring so as to act on the small 1st spring generation of R. (B.) microplus, in order to preclude the rise of the larger autumn generation. The overall treatment effect was positively significant in both schemes. The number of ticks observed in the control group was significantly higher than in the treated groups on all post-treatment counts. Group 2 exhibited more than 80% of efficacy almost throughout the study period, whereas Group 1 exhibited an efficacy percentage higher than 80% in September, October, December, February, April and May, but not in November (73.4%), January (58.3%), March (45.2%) or June (53.4%). Absolute control was observed in Group 2 in the counts of September and October, and in Group 1 in the count of February. The control strategies evaluated in this work provide an acceptable control level with only three applications of acaricides; at the same time, they prevent the occurrence of the autumn peak of tick burdens, which is characteristic of R. (B.) microplus in northwestern Argentina. Tick distribution was markedly aggregated in all counts. Although ticks were not distributed evenly among calves, the individual composition of the most heavily infested group was not consistent throughout the study period. In addition, the level of aggregation varied with tick abundance. These results suggest that applying acaricides to a portion of the herd or culling the most infested individuals at a given moment of the year may not be proper methods to achieve a significant control of R. (B.) microplus in northwestern Argentina. PMID:25670006

  5. Efficacy of pheromone-acaricide-impregnated tail-tag decoys for controlling the bont tick, Amblyomma hebraeum (Acari: Ixodidae), on cattle in Zimbabwe.

    PubMed

    Norval, R A; Sonenshine, D E; Allan, S A; Burridge, M J

    1996-01-01

    A large-scale field test using pheromone-acaricide-impregnated plastic tail-tag decoys demonstrated excellent efficacy of these devices for control of the bont tick, Amblyomma hebraeum, on cattle in Zimbabwe. The tail tags were impregnated with a mixture containing o-nitrophenol, methyl salicylate, 2,6-dichlorophenol and phenylacetaldehyde and one of three different acaricides (cyfluthrin, flumethrin or alphacypermethrin). o-Nitrophenol and methyl salicylate are components of the A. hebraeum attraction-aggregation-attachment pheromone, while 2,6-dichlorophenol and phenylacetaldehyde are proven attractants for this tick. Both o-nitrophenol and methyl salicylate were lost gradually from the tags over 12 and 14 week periods, respectively. In field trials, tick counts were compared between cattle that received tail tags either impregnated with pheromone mixture alone, cyfluthrin and pheromone mixture, flumethrin and pheromone mixture, alphacypermethrin and pheromone mixture or were left untreated. During the first 3 month trial period, control of adult bont ticks was 94.9% with cyfluthrin tail tags and 87.5% with flumethrin tail tags. In general, there was no significant difference in bont tick numbers on cattle without tags and those with tail tags containing pheromone only. When the trial was repeated for another 3 month period, control of bont ticks with tail tags containing cyfluthrin and flumethrin was 99.3 and 95.1%, respectively. However, control of bont ticks using alphacypermethrin was only 79.2%. Overall, retention of tail tags was excellent although some loss was encountered during the rainy season. In addition to controlling bont ticks, the tail tags provided moderate control of other tick species (Rhipicephalus evertsi evertsi, Rhipicephalus zambeziensis and Hyalomma spp.) simultaneously infesting cattle in the trials. PMID:8746132

  6. Acaricidal activity of four fractions and octadecanoic acid-tetrahydrofuran-3,4-diyl ester isolated from chloroform extracts of neem ( Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi larvae in vitro

    Microsoft Academic Search

    Yong-Hua Du; Jin-Liang Li; Ren-Yong Jia; Zhong-Qiong Yin; Xu-Ting Li; Cheng Lv; Gang Ye; Li Zhang; Yu-Qun Zhang

    2009-01-01

    Four fractions obtained from chloroform extracts of neem (Azadirachta indica) oil by column chromatography were investigated for acaricidal activity against Sarcoptes scabiei var. cuniculi larvae in vitro. Octadecanoic acid-tetrahydrofuran-3,4-diyl ester was isolated from an active fraction of the chloroform extract and its toxicity against S. scabiei larvae was tested in vitro. A complementary log–log model was used to analyse the

  7. Isolation and characterisation of acaricidal and larvicidal novel compound (2 S ,5 R ,6 R )-2-hydroxy-3,5,6-trimethyloctan-4-one from Streptomyces sp. against blood-sucking parasites

    Microsoft Academic Search

    Thimiri Lakshmipathi Deepika; Krishnan Kannabiran; Venkatesan Gopiesh Khanna; Govindasamy Rajakumar; Chidambaram Jayaseelan; Thirunavukkarasu Santhoshkumar; Abdul Abdul Rahuman

    The aim of the present study was to assess the acaricidal and larvicidal property of marine actinobacterial compound (2S,5R,6R)-2-hydroxy-3,5,6-trimethyloctan-4-one extracted and isolated from Streptomyces sp. VITDDK3 tested against the larvae of Rhipicephalus (Boophilus) microplus Canestrini (Acari: Ixodidae), Anopheles subpictus Grassi and Culex quinquefasciatus Say (Diptera: Culicidae). The isolate was taxonomically characterised, identified and designated as Streptomyces sp. VITDDK3. The crude

  8. Reprocessing of nonoptimally exposed holograms

    Microsoft Academic Search

    G. S. Phipps; C. E. Robertson; F. M. Tamashiro

    1980-01-01

    Two reprocessing techniques have been investigated that are capable of correcting the effects of nonoptimum optical density of photographic amplitude holograms recorded on Agfa-Gevaert type 10E75 plates. In some cases a reprocessed hologram will exhibit a diffraction efficiency even higher than that obtainable from a hologram exposed and processed to the optimum density. The SNR of the reprocessed holograms is

  9. Children Exposed to Interparental Violence

    Microsoft Academic Search

    Jacqueline G. Rea; B. B. Robbie Rossman

    2005-01-01

    In this longitudinal study of children exposed to interparental aggression (IPA) and violence, we examined whether maternal parenting style contributed to children's functioning over the course of one year (data were collected over three time points). Participants were mothers and children from the community and battered women's shelters. Battered mothers endorsed higher levels of Permissive parenting than did non-battered mothers.

  10. Application of ionic-liquid-supported magnetic dispersive solid-phase microextraction for the determination of acaricides in fruit juice samples.

    PubMed

    Zhang, Jiaheng; Li, Min; Li, Yubo; Li, Zongyang; Wang, Fenfen; Li, Qiu; Zhou, Wenfeng; Lu, Runhua; Gao, Haixiang

    2013-10-01

    In this study, ionic liquid (IL) supported magnetic dispersive solid-phase microextraction was developed and a systematic investigation was conducted on imidazolium ILs for their extraction performance. This nano-based pretreatment procedure was then applied for the determination of acaricides in fruit juice samples for the first time. A feature of this technique is that the commonly laborious chemical modification of magnetic nanoparticles (MNPs) was skillfully circumvented. Because of the combination of ILs, dispersive liquid-liquid microextraction, and dispersive MNP solid-phase microextraction, the extraction efficiency can be significantly improved using commercial MNPs. Parameters of the extraction method were investigated by one-factor-at-a-time approach. The optimal experimental conditions were as follows: emulsification for 2 min by sonication with the addition of 50 ?L [C6MIM][NTf2] in the dispersive liquid-liquid microextraction step and vortexing for 90 s after adding 40 mg spherical barium ferrite nanoparticles (20 nm). The desorption time was 2 min. Good linearity (0.5-500 ng/mL) and detection limits within the range of 0.05-0.53 ng/mL were achieved. The application of the proposed method was demonstrated by the analysis of real fruit juice samples, in which recoveries between 85.1 and 99.6% were obtained. PMID:23894018

  11. Evaluation of the acaricide effect of thymol, menthol, salicylic acid, and methyl salicylate on Boophilus microplus (Canestrini 1887) (Acari: Ixodidae) larvae.

    PubMed

    da Silveira Novelino, Adriana Maria; Daemon, Erik; Soares, Geraldo Luiz Gonçalves

    2007-08-01

    The tick Boophilus microplus is the principal species of ectoparasite that impairs dairy cattle productivity in Brazil. Its control is mainly by using synthetic chemical products during its parasitic phase. The purpose of this study is to evaluate the acaricide activity of four products of natural origin. Depending on solubility, tests were conducted with solutions in distilled water or emulsified in aqueous DMSO at 1% of the following products: thymol, menthol, methyl salicylate, and salicylic acid. Each of these was tested at three concentrations (0.25, 0.5, and 1.0%) with five repetitions. The "larval packet test" was performed on approximately 100 larvae of B. microplus at around 15 days of age. After applying the test substances, the envelopes were kept at 27 degrees C and UR >80% and opened after 24 h to count the living and dead larvae. Of the four products tested, only thymol caused significant (up to 100%) mortality of B. microplus larvae. The mortality caused by the other products varied from 0.52 to 9.76%. Hence, thymol can be considered a potential agent to control bovine ticks. PMID:17487509

  12. New method using quantitative PCR to follow the tick blood meal and to assess the anti-feeding effect of topical acaricide against Rhipicephalus sanguineus on dogs.

    PubMed

    Fourie, J J; Joubert, A; Labuschagné, M; Beugnet, F

    2014-05-01

    A 28-day study was conducted to assess the dynamic of blood feeding by Rhipicephalus sanguineus ticks on dogs treated or not with a novel topical combination of fipronil, amitraz and (S)-methoprene. Dogs were infested weekly through exposure to ticks in crates for 4h. Ticks were then counted in the crates at 2h and 4h post dog exposure. Ticks were also counted and removed from the dogs at 2h, 4h, 6h, 12h and 24h post tick exposure. The inhibition of blood feeding was assessed by both tick quantification and designing and performing a quantitative PCR (qPCR) to detect the canine hydroxymethylbilane synthase (HMBS) gene in ticks. The percentage of repellency sensu lato based on the ticks collected in crates at 2h varied from 4.7% at day 28 to 48.3% at day 7. The immediate mortality rate of the ticks expelled at 2h varied from 1.5% at day 21 to 31.7% at day 7. The efficacy calculation showed that the acaricidal combination started to kill ticks in as little as 2h. The average efficacy reached 90.0% at 12h post crate challenges and 100% at 24h post exposure in crates. The inclusion of an internal amplification control was used to ensure that no significant template-derived PCR inhibition (? 6.2%) affected the overall results. The reduction of blood feeding was significant at 4h (>80.0%) and >99.0% at 24h post tick exposure in the crate. The high repellency rate and the lethal efficacy of CERTIFECT(®) resulted in significantly fewer live attached ticks, consequently reducing blood intake and fluid exchanges. PMID:24656063

  13. [Drug Exposed Infants and Their Families.

    ERIC Educational Resources Information Center

    Fenichel, Emily, Ed.

    1992-01-01

    This bulletin issue addresses the theme of drug-exposed infants and the services required by these infants and their families. "Cocaine-Exposed Infants: Myths and Misunderstandings" (Barbara J. Myers and others) comments on the negative accounts of drug-exposed babies presented by mass media and reviews the mix of positive and negative findings…

  14. Insecticidal, acaricidal and repellent effects of DEET- and IR3535-impregnated bed nets using a novel long-lasting polymer-coating technique.

    PubMed

    Faulde, Michael K; Albiez, Gunther; Nehring, Oliver

    2010-03-01

    A novel long-lasting repellent-treated net (LLRTN) has been designed by binding the skin repellents N,N-diethyl-m-toluamide (DEET), or IR3535, onto the fibres of bed net fabric using a new polymer-coating technique. The repellent toxicological effectiveness and residual activity of a factory-based repellent-impregnated fabric has been evaluated by laboratory testing against adult Aedes aegypti mosquitoes and nymphal Ixodes ricinus ticks. By using this repellent-embedding impregnation technique, concentrations exceeding 10 g/m(2) could be achieved with one single polymer layer. Both DEET- and IR3535-impregnated fabrics revealed a dose-dependent insecticidal as well as acaricidal activity. One hundred percent knockdown times of DEET-treated bed nets ranged from 187.5 +/- 31.8 to 27.5 +/- 3.5 min against A. aegypti, and between 214 +/- 47 and 22.6 +/- 5 min against nymphal I. ricinus, linked to a DEET concentration of 1.08 and 10.58 g/m(2), respectively. With IR3535, A. aegypti produced dose-dependent 100% knockdown times varying from 87.5 +/- 10.6 to 57.5 +/- 3.5 min and between 131.4 +/- 6.5 and 33.8 +/- 5 min against nymphal I. ricinus, respectively, linked to concentrations between 1.59 and 10.02 g/m(2). One hundred percent repellency measured by complete landing and biting protection of impregnated fabric by using the arm-in-cage test could be achieved at DEET concentrations exceeding 3.7 to 3.9 g/m(2), and for IR3535 concentrations over 10 g/m(2). One hundred percent landing and biting protection could be preserved with DEET-treated fabrics for 29 weeks at an initial concentration of 4.66 g/m(2), 54 weeks at 8.8 g/m(2), 58 weeks at 9.96 g/m(2) and 61 weeks at 10.48 g/m(2) for DEET, and 23 weeks for IR3535-treated fabric at a concentration of 10.02 g/m(2). Unlike repellent-treated fabric, a brand of a commercially available long-lasting insecticide-treated net tested containing 500 mg permethrin/m(2) did not protect from mosquito bites. First results on bioactivity and long-lasting efficacy show that the new LLRTN technique is highly promising as a potential candidate for future malaria control strategies, especially in areas where pyrethroid resistance occurs. PMID:20162432

  15. MORTALITY OF SALMON FINGERLINGS EXPOSED TO PULSATING

    E-print Network

    MORTALITY OF SALMON FINGERLINGS EXPOSED TO PULSATING DIRECT CURRENT BY GERALD B. COLLINS, CHARLES D, current density, pulse frequency, and duration of exposure on the mortality of salmon fingerlings exposed, and pulse duration, using a current of square-wave form. The experiments indicated that mortality increased

  16. Orbital debris as detected on exposed spacecraft

    Microsoft Academic Search

    R. P. Bernhard; E. L. Christiansen; D. E. Kessler

    1997-01-01

    Spacecraft surfaces returned to the laboratory after being exposed to the low Earth orbit (LEO) environment have been examined by Scanning Electron Microscopy and Energy Dispersive X-ray (SEM\\/EDX) over the last two decades. Although many of these surfaces were not intended to be used as hypervelocity impact capture medium, meteoroid and orbital debris particles colliding with exposed surfaces are well

  17. Eryptosis in lead-exposed workers.

    PubMed

    Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

    2014-12-01

    Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8?g/dl) and non-exposed workers (4.2?g/dl). The exposure to lead produced an intoxication characterized by 88.3% less ?-aminolevulinic acid dehydratase (?ALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca(2+)]i and 1.6 times higher ?-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (<0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca(2+)], ?-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. PMID:25448684

  18. SUIVI MEDICAL DE SALARIES EXPOSES AU BERYLLIUM : Medical follow-up of beryllium -exposed workers

    E-print Network

    Boyer, Edmond

    1 SUIVI MEDICAL DE SALARIES EXPOSES AU BERYLLIUM : Medical follow-up of beryllium - exposed workers-up of beryllium-exposed workers. Method: a medical follow-up of workers from a factory machining beryllium (Be) either plain or as an alloy started in 2001. Be Lymphocyte Proliferation Tests (LPT) were performed

  19. Comparative Speed of Kill, Repellent (anti-feeding) and Acaricidal Efficacy of an Imidacloprid/Flumethrin Collar (Seresto(®)) and a Fipronil/(S)-Methoprene/Eprinomectin/Praziquantel Spot-on (Broadline (®)) against Ixodes ricinus (Linné, 1758) on Cats.

    PubMed

    Fourie, Josephus J; Horak, Ivan G; de Vos, Christa; Deuster, Katrin; Schunack, Bettina

    2015-08-01

    Speed of kill, repellent (anti-feeding) and acaricidal efficacy of an imidacloprid 10 % (w/w) /flumethrin 4.5 % (w/w) collar (Seresto(®), Bayer) and a spot-on formulation of fipronil 8.3 % (w/v) /(S)-methoprene 10 % (w/v) /eprinomectin 0.4 % (w/v) /praziquantel 8.3 % (w/v) (Broadline(®), Merial) against artificiallyinduced infestations with Ixodes ricinus on cats, were assessed in a parallel group design, randomised, controlled study. Twenty-four cats were included and randomly allocated to treatment groups or a non-treated control group. Starting on Day (D) 7 after treatment until D28, cats were each infested with 50 I. ricinus at weekly intervals. Ticks were counted in situ on the cats at 6, 12 and 24 h and upon removal 48 h after each infestation. Based on arithmetic means, Seresto(®) proved to be 100 % effective against adult I. ricinus at all assessment times (6, 12, 24 and 48 h after infestation) throughout the month-long study. Broadline(®) was 0 % to 16.7 % effective at 6 h, 26.8 % to 50.0 % effective at 12 h, while at 24 h after infestation efficacy peaked at 81.5 % on D15 declining to 31.5 % on D29. Based on the 48 h tick counts, the efficacy of Broadline(®) peaked at 100 % on D16 after treatment and decreased to 83.2 % by D30. The Seresto(®) collar provided significantly faster speed of kill and better persistent acaricidal effectiveness against Ixodes ricinus on cats compared to Broadline(®) spot-on. The additional repellent (anti-feeding) effect of Seresto(®) prevents parasites from taking a blood meal and thereby reduces the risk of vector-borne disease pathogen transmission. PMID:26152412

  20. Acaricidal effects of fluazuron (2.5?mg/kg) and a combination of fluazuron (1.6?mg/kg)?+?ivermectin (0.63?mg/kg), administered at different routes, against Rhipicephalus (Boophilus) microplus parasitizing cattle.

    PubMed

    Gomes, Lucas Vinicius Costa; Lopes, Welber Daniel Zanetti; Cruz, Breno Cayeiro; Teixeira, Weslen Fabricio; Felippelli, Gustavo; Maciel, Willian G; Bichuette, Murilo Abud; Ruivo, Maycon A; Alcantara Colli, Marcos Henrique; Carvalho, Rafael Silveira; Martinez, Antonio Campanha; Soares, Vando Edésio; da Costa, Alvimar José

    2015-06-01

    The present study aimed to evaluate the acaricidal efficacy of fluazuron (2.5?mg/kg), administered as a pour-on, in comparison to an injectable formulation containing fluazuron (1.6?mg/kg)?+?ivermectin (0.63?mg/kg), against Rhipicephalus (Boophilus) microplus in naturally and experimentally infested cattle. Two studies were conducted with different tick strains, one with artificial infestations (Stall Test, using leight animals per group) and one with natural infestations (utilizing ten animals per group). In both studies, the animals were randomized, according to average tick counts performed on days -3, -2 and -1, into four groups: T01, negative control (saline solution); T02, pour-on fluazuron (2.5?mg/kg); T03: subcutaneous fluazuron (1.6?mg/kg)?+?ivermectin (0.63?mg/kg); and T04 subcutaneous ivermectin (0.63?mg/kg). Based on obtained results, and considering the utilized tick strains, it was possible to conclude that the pour-on fluazuron (2.5?mg/kg) formulation demonstrated high acaricidal efficacy, with protection periods ranging from 49 to 77 days against Rhipicephalus (Boophilus) microplus. On the other hand, for the injectable fluazuron (1.6?mg/kg)?+?ivermectin (0.63?mg/kg) formulation, it was not possible to observe elevated anti-R. (B.) microplus effect on both artificial and experimental infestation studies. Results observed for this combination were similar or inferior to those obtained by subcutaneous ivermectin (0.63?mg/kg). Future studies with this formulation containing fluazuron (1.6?mg/kg)?+?ivermectin (0.63?mg/kg), regarding pharmacokinetic and/or bioavailability profiles, or even studies analyzing both this active principles separately, are needed, seeking to better understand the effects of such combination against Rhipicephalus (Boophilus) microplus parasitizing cattle. PMID:25728230

  1. Chemical composition and acaricidal activity of the essential oil of Baccharis dracunculifolia De Candole (1836) and its constituents nerolidol and limonene on larvae and engorged females of Rhipicephalus microplus (Acari: Ixodidae).

    PubMed

    de Assis Lage, Tiago Coelho; Montanari, Ricardo Marques; Fernandes, Sergio Antonio; de Oliveira Monteiro, Caio Márcio; de Oliveira Souza Senra, Tatiane; Zeringota, Viviane; da Silva Matos, Renata; Daemon, Erik

    2015-01-01

    Baccharis dracunculifolia DC (common name "alecrim-do-campo" in Brazil) is a plant with widespread distribution in South America that is the botanical origin of green propolis. The aim of this study was to evaluate the chemical composition and acaricidal activity of the essential oil of B.?dracunculifolia and its constituents nerolidol and limonene on unengorged larvae and engorged females of Rhipicephalus microplus (Acari: Ixodidae). The essential oil yield was 0.8% of dry mass and the major constituents were nerolidol (22.3%), germacrene D (7.2%), limonene (6.9%), ?-pinene (6.7) and bicyclogermacrene (6.5%). The acaricidal activity of the essential oil and the pure compounds nerolidol and (R)-(+)-limonene were assessed in the laboratory through the modified larval packet test (LPT) and the female immersion test (FIT). In the LPT, the essential oil and nerolidol were both active, causing more than 90% mortality at concentrations from 15.0 and 10.0?mg?mL(-1), respectively, whereas (R)-(+)-limonene was not active. In the FIT, the oil and nerolidol caused reduction in the quantity and quality of eggs produced, with control percentages of 96.3% and 90.3% at concentrations of 60.0 and 50.0?mg?mL(-1), respectively. It can be concluded that the essential oil obtained from the aerial parts of B.?dracunculifolia and its major component nerolidol have high activity on R.?microplus larvae and engorged females. PMID:25448290

  2. Assessment of low ABSPI among arsenic exposed and non-exposed populations: a pilot study.

    PubMed

    Khan, Manzurul Haque; Sarkar, Sudipta; Khan, Nasreen; Sarwar, A F M; Ahmad, S Akhtar

    2010-04-01

    This cross-sectional study was carried out to assess and compare Ankle Brachial Systolic Pressure Index (ABSPI) amongst 120 arsenic exposed and 120 non-exposed populations of Samta village in Bangladesh. Abnormal ABSPI was more prevalent in arsenic exposed (13.3%) than in non-exposed (2.5%) group. The prevalence of abnormal ABSPI for respondents when adjusted for age, sex, BMI, blood pressure status and diabetic status, the prevalence remain significantly different. The findings suggest that those exposed to arsenic have increased chance of having abnormal ABSP and hence increased chance of peripheral arterial disease in Bangladesh. PMID:21280555

  3. TREATMENT OF LEAD EXPOSED CHILDREN TRIAL

    EPA Science Inventory

    The Treatment of Lead-exposed Children (TLC) clinical trial compared the effect of lead chelation with succimer to placebo therapy. Outcomes included IQ, neuropsychological function, behavior, physical growth and blood pressure three years after initiation of treatment. Residenti...

  4. More Young Children Exposed to Marijuana

    MedlinePLUS

    ... fullstory_152987.html More Young Children Exposed to Marijuana, Study Finds Kids younger than 3 may eat ... HealthDay News) -- There's been a sharp increase in marijuana exposure among young children in the United States ...

  5. ERYTHROCYTE SURVIVAL IN SHEEP EXPOSED TO OZONE

    EPA Science Inventory

    Ozone has been reported to produce a variety of extrapulmonary effects including changes in the specific activity of some erythrocyte enzymes. Buckley et al. (1975) reported statistically significant extrapulmonary changes in a number of human volunteers experimentally exposed to...

  6. The astrobiological mission EXPOSE-R on board of the International Space Station

    NASA Astrophysics Data System (ADS)

    Rabbow, Elke; Rettberg, Petra; Barczyk, Simon; Bohmeier, Maria; Parpart, Andre; Panitz, Corinna; Horneck, Gerda; Burfeindt, Jürgen; Molter, Ferdinand; Jaramillo, Esther; Pereira, Carlos; Weiß, Peter; Willnecker, Rainer; Demets, René; Dettmann, Jan

    2015-01-01

    EXPOSE-R flew as the second of the European Space Agency (ESA) EXPOSE multi-user facilities on the International Space Station. During the mission on the external URM-D platform of the Zvezda service module, samples of eight international astrobiology experiments selected by ESA and one Russian guest experiment were exposed to low Earth orbit space parameters from March 10th, 2009 to January 21st, 2011. EXPOSE-R accommodated a total of 1220 samples for exposure to selected space conditions and combinations, including space vacuum, temperature cycles through 273 K, cosmic radiation, solar electromagnetic radiation at >110, >170 or >200 nm at various fluences up to GJ m-2. Samples ranged from chemical compounds via unicellular organisms and multicellular mosquito larvae and seeds to passive radiation dosimeters. Additionally, one active radiation measurement instrument was accommodated on EXPOSE-R and commanded from ground in accordance with the facility itself. Data on ultraviolet radiation, cosmic radiation and temperature were measured every 10 s and downlinked by telemetry and data carrier every few months. The EXPOSE-R trays and samples returned to Earth on March 9th, 2011 with Shuttle flight, Space Transportation System (STS)-133/ULF 5, Discovery, after successful total mission duration of 27 months in space. The samples were analysed in the individual investigators laboratories. A parallel Mission Ground Reference experiment was performed on ground with a parallel set of hardware and samples under simulated space conditions following to the data transmitted from the flight mission.

  7. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 false Brucellosis exposed swine. 78.32 Section 78.32 Animals... Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine. (a) Brucellosis exposed swine...

  8. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 false Brucellosis exposed swine. 78.32 Section 78.32 Animals... Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine. (a) Brucellosis exposed swine...

  9. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 false Brucellosis exposed swine. 78.32 Section 78.32 Animals... Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine. (a) Brucellosis exposed swine...

  10. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 false Brucellosis exposed swine. 78.32 Section 78.32 Animals... Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine. (a) Brucellosis exposed swine...

  11. 9 CFR 78.32 - Brucellosis exposed swine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 false Brucellosis exposed swine. 78.32 Section 78.32 Animals... Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine. (a) Brucellosis exposed swine...

  12. 9 CFR 78.8 - Brucellosis exposed cattle.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 false Brucellosis exposed cattle. 78.8 Section 78.8 Animals... Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.8 Brucellosis exposed cattle. Brucellosis exposed cattle may...

  13. 9 CFR 78.8 - Brucellosis exposed cattle.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 false Brucellosis exposed cattle. 78.8 Section 78.8 Animals... Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.8 Brucellosis exposed cattle. Brucellosis exposed cattle may...

  14. 9 CFR 78.8 - Brucellosis exposed cattle.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 false Brucellosis exposed cattle. 78.8 Section 78.8 Animals... Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.8 Brucellosis exposed cattle. Brucellosis exposed cattle may...

  15. 9 CFR 78.8 - Brucellosis exposed cattle.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 false Brucellosis exposed cattle. 78.8 Section 78.8 Animals... Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.8 Brucellosis exposed cattle. Brucellosis exposed cattle may...

  16. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 false Brucellosis exposed bison. 78.23 Section 78.23 Animals... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison. Brucellosis exposed bison may be...

  17. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 false Brucellosis exposed bison. 78.23 Section 78.23 Animals... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison. Brucellosis exposed bison may be...

  18. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 false Brucellosis exposed bison. 78.23 Section 78.23 Animals... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison. Brucellosis exposed bison may be...

  19. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 false Brucellosis exposed bison. 78.23 Section 78.23 Animals... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison. Brucellosis exposed bison may be...

  20. 9 CFR 78.23 - Brucellosis exposed bison.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 false Brucellosis exposed bison. 78.23 Section 78.23 Animals... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison. Brucellosis exposed bison may be...

  1. Cosmic radiation exposure of biological test systems during the EXPOSE-R mission

    NASA Astrophysics Data System (ADS)

    Berger, Thomas; Hajek, Michael; Bilski, Pawel

    2015-01-01

    In the frame of the EXPOSE-R mission outside the Russian Zvezda Module of the International Space Station (ISS) passive thermoluminescence dosimeters were applied to measure the radiation exposure of biological samples. The detectors were located beneath the sample carriers to determine the dose levels for maximum shielding. The dose measured beneath the sample carriers varied between 317 +/- 10 and 230 +/- 2 mGy, which amount to an average dose rate of 381 +/- 12 and 276 +/- 2 ?Gy d-1. These values are close to those assessed for the interior of the ISS and reflect the high shielding of the biological experiments within the EXPOSE-R facility. As a consequence of the high shielding (several g cm-2), the biological samples were predominantly exposed to galactic cosmic heavy ions and trapped protons in the Earth's radiation belts, whereas the trapped electrons did not reach the samples.

  2. Rural Canadian Youth Exposed to Physical Violence

    ERIC Educational Resources Information Center

    Laye, Adele M.; Mykota, David B.

    2014-01-01

    Exposure to physical violence is an unfortunate reality for many Canadian youth as it is associated with numerous negative psychosocial effects. The study aims to assist in understanding resilience in rural Canadian youth exposed to physical violence. This is accomplished by identifying the importance of protective factors, as measured by the…

  3. Exterior exposed ductwork: Delivery effectiveness and efficiency

    Microsoft Academic Search

    W. W. Delp; N. Matson; M. P. Modera

    1996-01-01

    Most of California`s light commercial buildings use air transport through ductwork for thermal distribution. The same air distribution systems are often used to provide both thermal comfort and ventilation. Some air distribution ductwork is installed on rooftops, exposed directly to the outside environment. As such, there exist potential energy penalties related to externally installed ductwork. In order to evaluate the

  4. Exposing origin-seeking bias in PSO

    Microsoft Academic Search

    Christopher K. Monson; Kevin D. Seppi

    2005-01-01

    We discuss testing methods for exposing origin-seeking bias in PSO motion algorithms. The strategy of resizing the initialization space, proposed by Gehlhaar and Fogel and made popular in the PSO context by Angeline, is shown to be insufficiently general for revealing an algorithm's tendency to focus its efforts on regions at or near the origin. An alternative testing method is

  5. Interviews with Children Exposed to Violence

    ERIC Educational Resources Information Center

    Eriksson, Maria; Nasman, Elisabet

    2012-01-01

    The aim of this article is to show how research practices may simultaneously follow principles of children's citizenship rights to participation and principles of protection and support when children exposed to violence are informants. The article focuses upon organisation of interview processes and interactions between adult researchers and child…

  6. Electroencephalographic findings in workers exposed to benzene.

    PubMed

    Kellerová, V

    1985-01-01

    Preventive EEG examination was carried out in 40 workers significantly exposed to benzene. The EEG findings were compared with those of a control group of 48 healthy persons, a group of 110 workers significantly exposed to toluene and xylene and a group of 236 workers exposed to vinyl chloride. The individuals exposed to benzene exhibited 22.5% of abnormal and 45% threshold findings, the abnormalities being episodic, diffuse or a combination of the two. The effect of benzene entailed a frequent (32.5%) occurrence of a characteristic frequency lability. Sleep phenomena were found in a total of 60% cases (37.5% cases reached stage 1 B3 while 15% reached stage 2 according to Roth [14]). The rapid onset of deeper sleep stages (in 30% cases) is considered typical for benzene exposure. The photic driving response often had an extended frequency range (a total of 61.1%, to beta frequencies only in 30.55%, to both beta and theta frequencies also in 30.55% of cases). The different EEG features characteristic of the neurotoxic action of various types of organic solvents make possible a more efficient diagnostics of the effects of these chemicals on the CNS. PMID:4086812

  7. Exposing Digital Forgeries in Complex Lighting Environments

    E-print Network

    Farid, Hany

    . The field of digital forensics has emerged over the past few years to combat this growing problem. Several of these forensic tools, we describe a new lighting-based digital forensic technique. M. Johnson (kimo1 Exposing Digital Forgeries in Complex Lighting Environments Micah K. Johnson, Student Member

  8. Interphase cytogenetics of workers exposed to benzene

    SciTech Connect

    Zhang, L.; Wang, Yunxia; Venkatesh, P. [Univ. of California, Berkeley, CA (United States)] [and others

    1996-12-01

    Fluorescence in situ hybridization (FISH) is a powerful new technique that allows numerical chromosome aberrations (aneuploidy) to be detected in interphase cells. In previous studies, FISH has been used to demonstrate that the benzene metabolites hydroquinone and 1,2,4-benzenetriol induce aneuploidy of chromosomes 7 and 9 in cultures of human cells. In the present study, we used an interphase FISH procedure to perform cytogenetic analyses on the blood cells of 43 workers exposed to benzene (median=31 ppm, 8-hr time-weighted average) and 44 matched controls from Shanghai, China. High benzene exposure (>31 ppm, n=22) increased the hyperdiploid frequency of chromosome 9 (p<0.01), but lower exposure (<31 ppm, n=21) did not. Trisomy 9 was the major form of benzene-induced hyperdiploidy. The level of hyperdiploidy in exposed workers correlated with their urinary phenol level (r= 0.58, p < 0.0001), a measure of internal benzene close. A significant correlation was also found between hyperdiploicly and decreased absolute lymphocyte count, an indicator of benzene hematotoxicity, in the exposed group (r=-0.44, p=0.003) but not in controls (r=-0.09, P=0.58). These results show that high benzene exposure induces aneuploidy of chromosome 9 in nondiseased individuals, with trisomy being the most prevalent form. They further highlight the usefulness of interphase cytogenetics and FISH for the rapid and sensitive detection of aneuploidy in exposed human populations. 35 refs., 3 figs., 2 tabs.

  9. Interphase cytogenetics of workers exposed to benzene.

    PubMed Central

    Zhang, L; Rothman, N; Wang, Y; Hayes, R B; Bechtold, W; Venkatesh, P; Yin, S; Wang, Y; Dosemeci, M; Li, G; Lu, W; Smith, M T

    1996-01-01

    Fluorescence in situ hybridization (FISH) is a powerful new technique that allows numerical chromosome aberrations (aneuploidy) to be detected in interphase cells. In previous studies, FISH has been used to demonstrate that the benzene metabolites hydroquinone and 1,2,4-benzenetriol induce aneuploidy of chromosomes 7 and 9 in cultures of human cells. In the present study, we used an interphase FISH procedure to perform cytogenetic analyses on the blood cells of 43 workers exposed to benzene (median = 31 ppm, 8-hr time-weighted average) and 44 matched controls from Shanghai, China. High benzene exposure (> 31 ppm, n = 22) increased the hyperdiploid frequency of chromosome 9 (p < 0.01), but lower exposure (< or = 31 ppm, n = 21) did not. Trisomy 9 was the major form of benzene-induced hyperdiploidy. The level of hyperploidy in exposed workers correlated with their urinary phenol level (r = 0.58, p < 0.0001), a measure of internal benzene dose. A significant correlation was also found between hyperdiploidy and decreased absolute lymphocyte count, an indicator of benzene hematotoxicity, in the exposed group (r = -0.44, p = 0.003) but not in controls (r = -0.09, p = 0.58). These results show that high benzene exposure induces aneuploidy of chromosome 9 in nondiseased individuals, with trisomy being the most prevalent form. They further highlight the usefulness of interphase cytogenetics and FISH for the rapid and sensitive detection of aneuploidy in exposed human populations. PMID:9118914

  10. Exposing the Mathematical Wizard: Approximating Trigonometric Functions

    ERIC Educational Resources Information Center

    Gordon, Sheldon P.

    2011-01-01

    For almost all students, what happens when they push buttons on their calculators is essentially magic, and the techniques used are seemingly pure wizardry. In this article, the author draws back the curtain to expose some of the mathematics behind computational wizardry and introduces some fundamental ideas that are accessible to precalculus…

  11. Surface contamination on LDEF exposed materials

    NASA Technical Reports Server (NTRS)

    Hemminger, Carol S.

    1992-01-01

    X-ray photoelectron spectroscopy (XPS) has been used to study the surface composition and chemistry of Long Duration Exposure Facility (LDEF) exposed materials including silvered Teflon (Ag/FEP), Kapton, S13GLO paint, quartz crystal monitors (QCM's), carbon fiber/organic matrix composites, and carbon fiber/Al Alloy composites. In each set of samples, silicones were the major contributors to the molecular film accumulated on the LDEF exposed surfaces. All surfaces analyzed have been contaminated with Si, O, and C; most have low levels (less than 1 atom percent) of N, S, and F. Occasionally observed contaminants included Cl, Na, K, P, and various metals. Orange/brown discoloration observed near vent slots in some Ag/FEP blankets were higher in carbon, sulfur, and nitrogen relative to other contamination types. The source of contamination has not been identified, but amine/amide functionalities were detected. It is probable that this same source of contamination account for the low levels of sulfur and nitrogen observed on most LDEF exposed surfaces. XPS, which probes 50 to 100 A in depth, detected the major sample components underneath the contaminant film in every analysis. This probably indicates that the contaminant overlayer is patchy, with significant areas covered by less that 100 A of molecular film. Energy dispersive x-ray spectroscopy (EDS) of LDEF exposed surfaces during secondary electron microscopy (SEM) of the samples confirmed contamination of the surfaces with Si and O. In general, particulates were not observed to develop from the contaminant overlayer on the exposed LDEF material surfaces. However, many SiO2 submicron particles were seen on a masked edge of an Ag/FEP blanket. In some cases such as the carbon fiber/organic matrix composites, interpretation of the contamination data was hindered by the lack of good laboratory controls. Examination of laboratory controls for the carbon fiber/Al alloy composites showed that preflight contamination was the most significant factor for all the contaminants generally detected at less than 1 atom percent, or detected only occasionally (i.e., all but Si, O, and C). Flight control surfaces, including sample backsides not exposed to space radiation or atomic oxygen flux, have accumulated some contamination on flight (compared to laboratory controls), but experimentally, the LDEF exposed surface contamination levels are generally higher for the contaminants Si and O. For most materials analyzed, Si contamination levels were higher on the leading edge surfaces than on the trailing edge surfaces. This was true even for the composite samples where considerable atomic oxygen erosion of the leading edge surfaces was observed by SEM. It is probable that the return flux associated with atmospheric backscatter resulted in enhanced deposition of silicones and other contaminants on the leading edge flight surfaces relative to the trailing edge. Although the Si concentration data suggested greater on-flight deposition of contaminants on the leading edge surfaces, the XPS analyses did not conclusively show different relative total thicknesses of flight deposited contamination for leading and trailing edge surfaces. It is possible that atomic oxygen reactions on the leading edge resulted in greater volatilization of the carbon component of the deposited silicones, effectively 'thinning' the leading edge deposited overlayer. Unlike other materials, exposed polymers such as Kapton and FEP-type Teflon had very low contamination on the leading edge surfaces. SEM evidence showed that undercutting of the contaminant overlayer and damaged polymer layers occurred during atomic oxygen erosion, which would enhance loss of material from the exposed surface.

  12. The EXPOSE-R Experiment ROSE-3 SPORES in artificial meteorites

    NASA Astrophysics Data System (ADS)

    Panitz, C.; Horneck, G.; Rabbow, E.; Rettberg, P.; Reitz, G.

    2011-10-01

    In the conducted experiment, spores of bacteria, fungi and ferns, especially adapted to survive extreme conditions, were either solely or embedded in artificial meteorites exposed to space environment in the ESA facility EXPOSE-R for 22 months (10.03.2009-21.02.2011). The experiment will provide experimental clues to the question whether meteorite material offers enough protection against the harsh environment of space for spores to survive a long-term stay in space. This question has received increased attention since the discovery of Martian meteorites has provided evidence that rocks can be transported from one planet to another in our solar

  13. Acaricidal activity of four fractions and octadecanoic acid-tetrahydrofuran-3,4-diyl ester isolated from chloroform extracts of neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi larvae in vitro.

    PubMed

    Du, Yong-Hua; Li, Jin-Liang; Jia, Ren-Yong; Yin, Zhong-Qiong; Li, Xu-Ting; Lv, Cheng; Ye, Gang; Zhang, Li; Zhang, Yu-Qun

    2009-07-01

    Four fractions obtained from chloroform extracts of neem (Azadirachta indica) oil by column chromatography were investigated for acaricidal activity against Sarcoptes scabiei var. cuniculi larvae in vitro. Octadecanoic acid-tetrahydrofuran-3,4-diyl ester was isolated from an active fraction of the chloroform extract and its toxicity against S. scabiei larvae was tested in vitro. A complementary log-log model was used to analyse the toxicity data. Activity was found in the third fraction, with 100% corrected mortality after 4.5 h of exposure at a concentration of 200 mg ml(-1). This fraction was repeatedly re-crystallised in acetone to yield a white amorphous powder, identified as octadecanoic acid-tetrahydrofuran-3,4-diyl ester, with a median lethal concentration (LC(50)) of 0.1 mg ml(-1) at 24 h post-treatment. The median lethal time (LT(50)) for this compound was 15.3 h at a concentration of 7.5 mg ml(-1). PMID:19443124

  14. Withdrawal Symptoms in Workers Exposed to Nitroglycerine

    PubMed Central

    Lund, R. P.; Häggendal, J.; Johnsson, G.

    1968-01-01

    Several reports during the last few years have described chest pain and sudden death in workers exposed to nitroglycol in combination with nitroglycerine. A report is given here of nine persons suffering from chest pain (including one sudden death) after exposure to nitroglycerine alone. The pains occurred between 30 and 65 hours after termination of the exposure. The differential diagnosis from angina pectoris is discussed. PMID:4967486

  15. Prenatal care in cocaine-exposed pregnancies

    Microsoft Academic Search

    Gene Burkett; Orlando Gomez-Marin; Salih Y Yasin; Marleny Martinez

    1998-01-01

    Objective: To examine the effect of prenatal care with and without drug rehabilitation on perinatal outcome in cocaine-using women.Methods: Cocaine-exposed pregnancies of 905 human immunodeficiency virus (HIV)-negative women were frequency matched (ratio 6:1) and compared with 150 nonusers. Cocaine subgroups consisted of 278 women who received prenatal care and drug rehabilitation (“comprehensive care”), 206 women who received prenatal care only,

  16. Children Exposed to War\\/Terrorism

    Microsoft Academic Search

    Jon A. Shaw

    2003-01-01

    This paper reviews the prevalence of psychological morbidities in children who have been exposed to war-related traumas or terrorism as well as the diversity of war-related casualties and their associated psychological responses. The psychological responses to war-related stressors are categorized as (1) little or no reaction, (2) acute emotional and behavioral effects, and (3) long-term effects. Specific categories of war-related

  17. Work ability in vibration-exposed workers

    PubMed Central

    Hagberg, M.

    2014-01-01

    Background Hand–arm vibration exposure may cause hand–arm vibration syndrome (HAVS) including sensorineural disturbances. Aims To investigate which factors had the strongest impact on work ability in vibration-exposed workers. Methods A cross-sectional study in which vibration-exposed workers referred to a department of occupational and environmental medicine were compared with a randomized sample of unexposed subjects from the general population of the city of Gothenburg. All participants underwent a structured interview, answered several questionnaires and had a physical examination including measurements of hand and finger muscle strength and vibrotactile and thermal perception thresholds. Results The vibration-exposed group (47 subjects) showed significantly reduced sensitivity to cold and warmth in digit 2 bilaterally (P < 0.01) and in digit 5 in the left hand (P < 0.05) and to warmth in digit 5 in the right hand (P < 0.01), compared with the 18 referents. Similarly, tactilometry showed significantly raised vibration perception thresholds among the workers (P < 0.05). A strong relationship was found for the following multiple regression model: estimated work ability = 11.4 ? 0.1 × age ? 2.3 × current stress level ? 2.5 × current pain in hands/arms (multiple r = 0.68; P < 0.001). Conclusions Vibration-exposed workers showed raised vibrotactile and thermal perception thresholds, compared with unexposed referents. Multiple regression analysis indicated that stress disorders and muscle pain in hands/arms must also be considered when evaluating work ability among subjects with HAVS. PMID:25145484

  18. Epitopes exposed on hepatitis delta virus ribonucleoproteins.

    PubMed Central

    Bichko, V V; Lemon, S M; Wang, J G; Hwang, S; Lai, M M; Taylor, J M

    1996-01-01

    A total of 17 antibodies, raised in several nonhuman species and specific for different regions on the delta antigen (delta Ag), were used to map, via immunoprecipitation, those domains exposed on the surface of the viral ribonucleoprotein (RNP). These studies showed that the domains for the nuclear localization signal and the C-terminal extension, unique to the large form of delta Ag, are exposed. Also exposed is the C-terminal region of the small form of delta Ag. In contrast, reactivity was not found with the coiled-coil domain needed for protein dimerization. When the hepatitis delta virus (HDV) RNA was released by treatment of viral RNP with vanadyl ribonucleoside complexes, no change in the pattern of delta Ag epitope presentation was detected, consistent with the interpretation that a multimeric protein structure persists in the absence of RNA. These RNP studies have implications not only for understanding of the process of HDV assembly but also for evaluation of the immune responses of an infected host to HDV replication. PMID:8709197

  19. The PUR Experiment on the EXPOSE-R facility: biological dosimetry of solar extraterrestrial UV radiation

    NASA Astrophysics Data System (ADS)

    Bérces, A.; Egyeki, M.; Fekete, A.; Horneck, G.; Kovács, G.; Panitz, C.

    2015-01-01

    The aim of our experiment Phage and Uracil Response was to extend the use of bacteriophage T7 and uracil biological dosimeters for measuring the biologically effective ultraviolet (UV) dose in the harsh extraterrestrial radiation conditions. The biological detectors were exposed in vacuum-tightly cases in the European Space Agency (ESA) astrobiological exposure facility attached to the external platform of Zvezda (EXPOSE-R). EXPOSE-R took off to the International Space Station (ISS) in November 2008 and was installed on the External platform of the Russian module Zvezda of the ISS in March 2009. Our goal was to determine the dose-effect relation for the formation of photoproducts (i.e. damage to phage DNA and uracil, respectively). The extraterrestrial solar UV radiation ranges over the whole spectrum from vacuum-UV (?<200 nm) to UVA (315 nm

  20. Rescue of fish exposed to a lethal dose of pathogen, by signals from sublethally exposed survivors.

    PubMed

    Mothersill, Carmel; Austin, Dawn; Fernandez-Palomo, Cristian; Seymour, Colin; Auchinachie, Niall; Austin, Brian

    2015-03-01

    Rainbow trout (Oncorhynchus mykiss, Walbaum) were challenged intraperitoneally with a sublethal dose of Vibrio anguillarum VIB1 and allowed to recover. Then, after 7 days, naïve fish, (designated as 'bystander' fish) which had never been exposed to the pathogen, were introduced to the same tank. These swam with the adapted (recovered) fish for 7 days before both groups and a control (never exposed directly to the pathogen or to recovered fish) group were exposed to a lethal dose of VIB1. Mortality records were 100% in the control group within 3 days, 47% in the adapted group and 60% in the unchallenged bystander group, which swam with the adapted group. In both the latter groups, the time to death of the non-surviving fish was attenuated. This inter-animal communication of signals has previously been documented for animals exposed to ionizing radiation. Assays of tissues from control, challenged and 'bystander fish exposed to the pathogen showed that a signal as yet unidentified but similar to that seen in bystanders to irradiated fish was being produced. This signal caused a sharp and transient increase in intracellular calcium and a decrease in clonogenicity in a well-characterized reporter assay. PMID:25757731

  1. Mortality patterns among workers exposed to acrylamide

    SciTech Connect

    Collins, J.J.; Swaen, G.M.; Marsh, G.M.; Utidjian, H.M.; Caporossi, J.C.; Lucas, L.J. (American Cyanamid Co., Wayne, NJ (USA))

    1989-07-01

    A cohort of 8854 men, 2293 of whom were exposed to acrylamide, was examined from 1925 to 1983 for mortality. This cohort consisted of four plant populations in two countries: the United States and The Netherlands. No statistically significant excess of all-cause or cause-specific mortality was found among acrylamide workers. Analysis by acrylamide exposure levels showed no trend of increased risk of mortality from several cancer sites. These results do not support the hypothesis that acrylamide is a human carcinogen.

  2. An exploratory study to assess the activity of the acarine growth inhibitor, fluazuron, against Sarcoptes scabei infestation in pigs

    PubMed Central

    2012-01-01

    Background The most common treatments for scabies in human and veterinary settings are topical 5% permethrin or systemic treatment with ivermectin. However, these treatments have very little activity against arthropod eggs, and therefore repeated treatment is frequently required. In-vitro, biochemical and molecular studies have demonstrated that human mites are becoming increasingly resistant to both acaricides. To identify alternate acaricides, we undertook a pilot study of the in vivo activity of the benzoylphenyl urea inhibitor of chitin synthesis, fluazuron, in pigs with sarcoptic mange. Findings Pigs (n = 5) were infested with S. scabei var suis, and randomised to treatment at the start of peak infestation with fluazuron at a dose of 10 mg/kg/day per os for 7 days (n = 3) or no treatment (n = 2). Clinical scores, skin scrapings for mite counts and blood sampling for pharmacokinetic analysis were undertaken. Fluazuron was well absorbed in treated pigs with measureable blood levels up to 4 weeks post treatment. No adverse effects were observed. Modest acaricidal activity of the compound was observed, with a reduction in severity of skin lesions in treated pigs, as well as a reduction in number of scabies mite's early life stages. Conclusions The moderate efficacy of fluazuron against scabies mites indicates a lead to the development of alternate treatments for scabies, such as combination therapies that maybe applicable for human use in the future. PMID:22336283

  3. The ORGANIC Experiment on EXPOSE-R on the ISS: A Space Exposure Experiment

    NASA Astrophysics Data System (ADS)

    Bryson, Kathryn; Peeters, Z.; Salama, F.; Foing, B.; Ehrenfreund, P.; Ricco, A. J.; Jessberger, E.; Bischoff, A.; Breitfellner, M.; Schmidt, W.; Robert, F.

    2012-05-01

    Aromatic networks are among the most abundant organic material in space. PAHs and fullerenes have been identified in meteorites and are thought to be among the carriers for numerous astronomical absorption and emission features. Thin films of selected PAHs and fullerenes have been subjected to the low Earth orbit environment as part of the ORGANIC experiment on the multi-user facility EXPOSE-R onboard the International Space Station. The ORGANIC experiment monitored the chemical evolution, survival, destruction, and chemical modification of the samples in space environment. EXPOSE-R with its experiment inserts was mounted on the outside of the ISS from March 10, 2009 to January 21, 2011. The samples were returned to Earth and inspected in spring 2011. The 682-day period outside the ISS provided continuous exposure to the cosmic-, solar-, and trapped-particle radiation background and >2500 h of unshadowed solar illumination. All trays carry both solar-irradiation-exposed and dark samples shielded from the UV photons, enabling discrimination between the effects of exposure to solar photons and cosmic rays. The samples were analyzed before exposure to the space environment with UV-VIS spectroscopy. Ground truth monitoring of additional sample carriers was performed through UV-VIS spectroscopy at regular intervals at NASA Ames Research Center. During the exposure on the ISS, two control sample carriers were exposed with a slight time shift in a planetary simulation chamber at the Microgravity User Support Center (MUSC) at DLR. Vacuum, UV radiation, and temperature fluctuations are simulated according to the telemetry data measured during flight. The spectroscopic measurements of these two carriers have been performed together with the returned flight samples. We report on the scientific experiment, the details of the ground control analysis, and preliminary flight sample results. We discuss how extended space exposure experiments allow to enhance our knowledge on the evolution of organic compounds in space.

  4. The ORGANIC Experiment on EXPOSE-R on the ISS: A Space Exposure Experiment

    NASA Astrophysics Data System (ADS)

    Bryson, Kathryn; Peeters, Z.; Salama, F.; Foing, B.; Ehrenfreund, P.; Ricco, A.; Jessberger, E. K.; Bischoff, A.; Breitfellner, M.; Schmidt, W.; Robert, F.

    2013-06-01

    Aromatic networks are among the most abundant organic material in space. PAHs and fullerenes have been identified in meteorites and are thought to be among the carriers for numerous astronomical absorption and emission features. Thin films of selected PAHs and fullerenes have been subjected to the low Earth orbit environment as part of the ORGANIC experiment on the multi-user facility EXPOSE-R onboard the ISS. The ORGANIC experiment monitored the chemical evolution, survival, destruction, and chemical modification of the samples. EXPOSE-R was mounted on the outside of the ISS from March 10, 2009 to January 21, 2011. The samples were returned to Earth and inspected in spring 2011. The 682-day period outside the ISS provided continuous exposure to the cosmic-, solar-, and trapped-particle radiation background and >2500 h of unshadowed solar illumination. All trays carry both solar-irradiation-exposed and dark samples shielded from the UV photons, enabling discrimination between the effects of exposure to solar photons and cosmic rays. The samples were analyzed before exposure to the space environment with UV-VIS spectroscopy. Ground truth monitoring of additional sample carriers was performed through UV-VIS spectroscopy at regular intervals at NASA Ames Research Center. During the exposure on the ISS, 2 control sample carriers were exposed with a slight time shift in a planetary simulation chamber at the Microgravity User Support Center at DLR. Vacuum, UV radiation, and temperature fluctuations are simulated according to the telemetry data measured during flight. The spectroscopic measurements of these two carriers have been performed together with the returned flight samples. We report on the scientific experiment, the details of the ground control analysis, and preliminary flight sample results.

  5. Erythrocyte survival in sheep exposed to ozone

    SciTech Connect

    Moore, G.S.; Calabrese, E.J.; Labato, F.J.

    1981-07-01

    Erythrocyte survival studies in the Dorset ewe using chromium 51 were performed. The purpose of the study was to determine if ozone exposure produces decreased cell survival which may be the result of premature erythrocyte aging. This strain of sheep has an erythrocyte glucose-6-phosphate dehydrogenase (G6PD) activity that is very low, being comparable to human A-variants with G6PD deficiency. Ozone exposure may produce hemolytic effects in G6PD deficients more readily than in erythrocytes with normal activity. A decrease in hematocrit was observed in the ozone exposed groups. With respect to red cell destruction, ozone does not appear to act immediately, but rather there appears to be a delayed effect. At 0.25 ppM ozone, the group reached the 50% remaining level an average of 1 day sooner than the control group. There was no significant difference between control and exposed groups at the 0.50 ppM and 0.70 ppM levels. Also, the results demonstrate a net decrease in hematocrit which is greater for 0.25 ppM ozone than any other exposure level. (RJC)

  6. First results of the ORGANIC experiment on EXPOSE-R on the ISS

    NASA Astrophysics Data System (ADS)

    Bryson, K. L.; Salama, F.; Elsaesser, A.; Peeters, Z.; Ricco, A. J.; Foing, B. H.

    2015-01-01

    The ORGANIC experiment on EXPOSE-R spent 682 days outside the International Space Station, providing continuous exposure to the cosmic-, solar- and trapped-particle radiation background for fourteen samples: 11 polycyclic aromatic hydrocarbons (PAHs) and three fullerenes. The thin films of the ORGANIC experiment received, during space exposure, an irradiation dose of the order of 14 000 MJ m-2 over 2900 h of unshadowed solar illumination. Extensive analyses were performed on the returned samples and the results compared to ground control measurements. Analytical studies of the returned samples included spectral measurements from the vacuum ultraviolet to the infrared range and time-of-flight secondary ion mass spectrometry. Limited spectral changes were observed in most cases pointing to the stability of PAHs and fullerenes under space exposure conditions. Furthermore, the results of these experiments confirm the known trend in the stability of PAH species according to molecular structure: compact PAHs are more stable than non-compact PAHs, which are themselves more stable than PAHs containing heteroatoms, the last category being the most prone to degradation in the space environment. We estimate a depletion rate of the order of 85 +/- 5% over the 17 equivalent weeks of continuous unshadowed solar exposure in the most extreme case tetracene (smallest, non-compact PAH sample). The insignificant spectral changes (below 10%) measured for solid films of large or compact PAHs and fullerenes indicate a high stability under the range of space exposure conditions investigated on EXPOSE-R.

  7. Dust release from surfaces exposed to plasma

    SciTech Connect

    Flanagan, T. M.; Goree, J. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States)

    2006-12-15

    Micrometer-sized particles adhered to a surface can be released when exposed to plasma. In an experiment with a glass surface coated with lunar-simulant dust, it was found that particle release requires exposure to both plasma and an electron beam. The dust release rate diminishes almost exponentially in time, which is consistent with a random process. As proposed here, charges of particles adhered to the surface fluctuate. These charges experience a fluctuating electric force that occasionally overcomes the adhesive van der Waals force, causing particle release. The release rate increases with plasma density, so that plasma cleaning is feasible at high plasma densities. Applications of this cleaning include controlling particulate contamination in semiconductor manufacturing, dust mitigation in the exploration of the moon and Mars, and dusty plasmas.

  8. Comparative genomic hybridization study of arsenic-exposed and non-arsenic-exposed urinary transitional cell carcinoma

    SciTech Connect

    Hsu, L.-I [Genomics Research Center, Academia Sinica, Taipei, Taiwan (China); Chiu, Allen W. [Department of Urology, Taipei City Hospital Zhongxiao Branch, Taipei, Taiwan (China); Pu, Y.-S. [Department of Urology, National Taiwan University Hospital, Taipei, Taiwan (China); Wang, Y.-H. [School of Public Health, Taipei Medical University, Taipei, Taiwan (China); Huan, Steven K. [Division of Urology, Department of Surgery, Chi-Mei Medical Center, Tainan, Taiwan (China); Hsiao, C.-H. [Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan (China); Hsieh, F.-I [School of Public Health, Taipei Medical University, Taipei, Taiwan (China); Chen, C.-J. [Genomics Research Center, Academia Sinica, Taipei, Taiwan (China)], E-mail: hsu277@yahoo.com.tw

    2008-03-01

    To compare the differences in DNA aberrations between arsenic-exposed and non-arsenic-exposed transitional cell carcinoma (TCC), we analyzed 19 arsenic-exposed and 29 non-arsenic-exposed urinary TCCs from Chi-Mei Hospital using comparative genomic hybridization. DNA aberrations were detected in 42 TCCs including 19 arsenic-exposed and 23 non-arsenic-exposed TCCs. Arsenic-exposed TCCs had more changes than unexposed TCCs (mean {+-} SD, 6.6 {+-} 2.9 vs. 2.9 {+-} 2.2). Arsenic exposure was significantly associated with the number of DNA aberrations after adjustment for tumor stage, tumor grade and cigarette smoking in multiple regression analysis. The most frequent DNA gains, which were strikingly different between arsenic-exposed and non-arsenic-exposed TCCs, included those at 1p, 4p, 4q and 8q. A much higher frequency of DNA losses in arsenic-exposed TCCs compared with non-arsenic-exposed TCCs was observed in 10q, 11p and 17p. Chromosomal loss in 17p13 was associated not only with arsenic exposure, but also with tumor stage and grade. The p53 immunohistochemistry staining showed that chromosome 17p13 loss was associated with either p53 no expression (25%) or p53 overexpression (75%). The findings suggest that long-term arsenic exposure may increase the chromosome abnormality in TCC, and 17p loss plays an important role in arsenic-induced urinary carcinogenesis.

  9. Antinuclear antibody and rheumatoid factor in silica-exposed workers.

    PubMed

    Aminian, Omid; Sharifian, Seyed Akbar; Mehrdad, Ramin; Haghighi, Khosro Sadeghniyat; Mazaheri, Maria

    2009-06-01

    A lot of workers in industries such as foundry, stonecutting, and sandblasting are exposed to higher than permissible levels of crystalline silica. Various alterations in humoral immune function have been reported in silicosis patients and workers exposed to silica dust. The aim of this study was to measure antinuclear antibody (ANA) and rheumatoid factor (RF) levels in foundry workers exposed to silica and to compare them with a control group without such exposure. ANA and RF were measured in 78 exposed and 73 non-exposed workers, and standard statistical methods were used to compare them. The two groups did not significantly differ in age and smoking. Mean work duration of the exposed and non-exposed workers was (14.9+/-4.72) years and (12.41+/-6.3) years, respectively. Ten exposed workers had silicosis. ANA was negative in all workers in either group. Its mean titer did not differ significantly between the exposed and control workers [(0.39+/-0.15) IU mL(-1) vs. (0.36+/-0.17) IU mL(-1), respectively]. RF was positive in two workers of each group. Other studies have reported an increase in ANA and RF associated with exposure to silica dust and silicosis.In contrast, our study suggests that exposure to silica dust does not increase the level of ANA and RF in exposed workers. PMID:19581212

  10. Comparative Study of Liver Cancer Patients in Arsenic Exposed and Non-exposed Areas of Pakistan

    Microsoft Academic Search

    Sham Kumar Wadhwa; Tasneem Gul Kazi; Akhtar Ali Chandio; Hassan Imran Afridi; Nida Fatima Kolachi; Sumaira Khan; Ghulam Abbas Kandhro; Syeda Nasreen; Abdul Qadir Shah; Jameel Ahmed Baig

    The investigated data shows that arsenic (As) in drinking water is associated with increased mortality from different types\\u000a of cancers including liver cancer. In this study, blood and scalp hair samples of male liver cancer patients and healthy referents\\u000a belonging to As exposed areas of Sindh Pakistan were analyzed for As contents. The As levels in drinking water of understudy

  11. Neurotoxicity of Acrylamide in Exposed Workers

    PubMed Central

    Pennisi, Manuela; Malaguarnera, Giulia; Puglisi, Valentina; Vinciguerra, Luisa; Vacante, Marco; Malaguarnera, Mariano

    2013-01-01

    Acrylamide (ACR) is a water-soluble chemical used in different industrial and laboratory processes. ACR monomer is neurotoxic in humans and laboratory animals. Subchronic exposure to this chemical causes neuropathies, hands and feet numbness, gait abnormalities, muscle weakness, ataxia, skin and in some cases, cerebellar alterations. ACR neurotoxicity involves mostly the peripheral but also the central nervous system, because of damage to the nerve terminal through membrane fusion mechanisms and tubulovescicular alterations. Nevertheless, the exact action mechanism is not completely elucidated. In this paper we have reviewed the current literature on its neurotoxicity connected to work-related ACR exposure. We have analyzed not only the different pathogenetic hypotheses focusing on possible neuropathological targets, but also the critical behavior of ACR poisoning. In addition we have evaluated the ACR-exposed workers case studies. Despite all the amount of work which have being carried out on this topic more studies are necessary to fully understand the pathogenetic mechanisms, in order to propose suitable therapies. PMID:23985770

  12. Infectivity of rabies virus-exposed macrophages.

    PubMed

    Nazé, Florence; Suin, Vanessa; Lamoral, Sophie; Francart, Aurélie; Brochier, Bernard; Roels, Stefan; Mast, Jan; Kalai, Michael; Van Gucht, Steven

    2013-02-01

    Rabies virus distributes widely in infected mice, including lymphoid tissues and spleen macrophages. The infection characteristics in murine macrophages and the infectivity of virus-exposed macrophages were examined upon inoculation in mice. In vitro, Mf4/4 spleen macrophages supported mild virus production (10(4)-fold less than neuroblastoma), with formation of typical virions. Bone marrow-derived macrophages (BMM) were most efficient to capture virus, but new virus production was not detected. Virus-induced cell death was significantly stronger in BMM, which might have eliminated BMM with productive infection. Still, viral RNA remained detectable in the remaining BMM for at least 4 weeks. Injection of in vitro-infected Mf4/4 in the nose or brain proved efficient to propagate infection in mice, even when cells were pre-incubated with neutralizing antibodies. Surprisingly, injection of ex-vivo-infected BMM in the brain also led to lethal infection in 8 out of 12 mice. Injection of infected Mf4/4 in the muscle mostly favoured a protective antibody response. Despite that macrophages are less fit to support virus production, they can still act as a source of infectious virus upon transfer in mice. This may be relevant for screening donor organs/cells, for which RT-PCR should be preferred over the traditional antigen or virus isolation assays. PMID:23159243

  13. Cytogenetic analyses of mice exposed to dichloromethane

    SciTech Connect

    Allen, J.; Kligerman, A.; Campbell, J.; Westbrook-Collins, B.; Erexson, G.; Kari, F.; Zeiger, E. (National Institute of Environmental Health Sciences, Research Triangle Park, NC (USA))

    1990-01-01

    Chromosome damage was studied in female B6C3F1 mice exposed to dichloromethane (DCM) by subcutaneous or inhalation treatments. No increase in the frequency of either sister chromatid exchanges (SCEs) or chromosome aberrations (CAs) in bone marrow cells was observed after a single subcutaneous injection of 2,500 or 5,000 mg/kg DCM. Inhalation exposure to DCM for 10 days at concentrations of 4,000 or 8,000 ppm resulted in significant increases in frequencies of SCEs in lung cells and peripheral blood lymphocytes, CAs in lung and bone marrow cells, and micronuclei (MN) in peripheral blood erythrocytes. Lung cell CAs and blood erythrocyte MN reached frequencies of approximately two times control levels. Following a 3-month inhalation exposure to 2,000 ppm DCM, mice showed small but significant increases in lung cell SCEs and peripheral blood erythrocyte MN. These findings suggest that genotoxicity may play a role in the carcinogenicity of DCM in the lungs of B6C3F1 female mice.

  14. Accutane-exposed pregnancies--California, 1999.

    PubMed

    2000-01-21

    Accutane (Roche Laboratories, Nutley, New Jersey), known by the generic name "isotretinoin," is a prescription oral medication approved by the Food and Drug Administration (FDA) to treat severe, recalcitrant nodular acne. It is also a known human teratogen that can cause multiple major malformations. Embryopathy associated with the mother's exposure to isotretinoin during the first trimester of pregnancy includes craniofacial, cardiac, thymic, and central nervous system malformations . In response to FDA recommendations, the manufacturer began a pregnancy-prevention program (PPP) in 1988 that included educational materials for physicians and patients and offered women reimbursement for contraceptive counseling by a physician. The PPP coordinators asked reproductive-aged women being treated with isotretinoin to enroll voluntarily in the Boston University Accutane Survey (BUAS). The total number of reproductive-aged women taking isotretinoin in the United States is unknown; however, 454,273 women enrolled in the BUAS from 1989 to October 1999. BUAS has estimated that 38%-40% of reproductive-aged women taking isotretinoin chose to enroll in the survey (BUAS, unpublished data, 1999). Although isotretinoin is contraindicated in pregnancy and has a package label warning users to avoid pregnancy while taking it, exposed pregnancies occur. Approximately 900 pregnancies occurred among BUAS enrollees during 1989-1998 (BUAS, unpublished data, 1999). Roche Laboratories began direct-to-consumer print advertisements in 1996, added television and radio advertisements to selected cities in 1997, and expanded the campaign to the entire United States in 1998. PMID:10680601

  15. Respiratory morbidity in workers exposed to dust containing phenolic resin

    Microsoft Academic Search

    Patricia Jo Sparks; John M. Peters

    1980-01-01

    Summary Seventy-three men and women exposed to phenolic resin dust and\\/or processed cotton dust in a factory producing sound-deadening material were studied cross-sectionally. There was a statistically significant acute drop in FEV1 and FVC over the shift in garnett-line workers exposed to dust containing phenolic resin. Pickers, exposed to processed cotton dust only, did not show a significant drop in

  16. Synthesizing Regularity Exposing Attributes in Large Protein Databases

    E-print Network

    de la Maza, Michael

    1993-05-01

    This thesis describes a system that synthesizes regularity exposing attributes from large protein databases. After processing primary and secondary structure data, this system discovers an amino acid representation ...

  17. Degradation of HEPA filters exposed to DMSO

    SciTech Connect

    Bergman, W.; Wilson, K.; Larsen, G.; Lopez, R.; LeMay, J.

    1994-07-11

    Dimethyl sulfoxide (DMSO) sprays are being used to remove the high explosive (HE) from nuclear weapons in the process of their dismantlement. A boxed 50 cfm HEPA filter with an integral prefilter was exposed to DMSO vapor and aerosols that were generated by a spray nozzle to simulate conditions expected in the HE dissolution operation. After 198 hours of operation, the pressure drop of the filter had increased from 1.15 inches to 2.85 inches, and the efficiency for 0.3 {mu}m dioctyl sebacate (DOS) aerosols decreased from 99.992% to 98.6%. Most of the DMSO aerosols had collected as a liquid pool inside the boxed HEPA. The liquid was blown out of the filter exit with 100 cfm air flow at the end of the test. Since the filter still met the minimum allowed efficiency of 99.97% after 166 hours of exposure, we recommend replacing the filter every 160 hours of operation or sooner if the pressure drop increases by 50%. Examination of the filter showed that visible cracks appeared at the joints of the wooden frame and a portion of the sealant had pulled away from the frame. Since all of the DMSO will be trapped in the first HEPA filter, the second HEPA filter should not suffer from DMSO degradation. Thus the combined efficiency for the first filter (98.6%) and the second filter (99.97%) is 99.99996% for 0.3{mu}m particles. If the first filter is replaced prior to its degradation, each of the filters will have 99.97% efficiency, and the combined efficiency will be 99.999991%. The collection efficiency for DMSO/HE aerosols will be much higher because the particle size is much greater.

  18. The ORGANIC experiment on EXPOSE-R on the ISS: Flight sample preparation and ground control spectroscopy

    Microsoft Academic Search

    K. L. Bryson; Z. Peeters; F. Salama; B. Foing; P. Ehrenfreund; A. J. Ricco; E. Jessberger; A. Bischoff; M. Breitfellner; W. Schmidt; F. Robert

    2011-01-01

    In March of 2009, the ORGANIC experiment integrated into the European multi-user facility EXPOSE-R, containing experiments dedicated to Astrobiology, was mounted through Extra Vehicular Activity (EVA) externally on the International Space Station (ISS). The experiment exposed organic samples of astronomical interest for a duration of 97weeks (?22months) to the space environment. The samples that were returned to Earth in spring

  19. 9 CFR 78.8 - Brucellosis exposed cattle.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...follows: (1) Such brucellosis exposed cattle from herds known to be affected other than female cattle which...months of age and nursing brucellosis exposed cows in a herd subjected to a herd blood test within 10 days prior to interstate...

  20. Water uptake by sunlight and ozone exposed diesel exhaust particles

    Microsoft Academic Search

    Matti Vartiainen; Stephen R. McDow; Richard M. Kamens

    1996-01-01

    Two types of experiments were conducted to investigate the effect of aerosol aging on water uptake by diesel soot particles. First, in three experiments diluted diesel soot was exposed to sunlight for up to 10 hours in a 190 m3 Teflon film smog chamber and filter samples were collected at various time intervals. Second, diesel soot filter samples were exposed

  1. Foliar Lead Uptake by Lettuce Exposed to Atmospheric Fallouts

    E-print Network

    Mailhes, Corinne

    Foliar Lead Uptake by Lettuce Exposed to Atmospheric Fallouts G A ¨E L L E U Z U , S O P H I E S O gardens near industrial plants. The mechanisms of foliar uptake of lead by lettuce (Lactuca sativa) exposed to the atmospheric fallouts of a lead-recycling plant were studied. After43daysofexposure

  2. Exposing Inconsistent Web Search Results with Bobble Xinyu Xing1

    E-print Network

    Wang, Deli

    Exposing Inconsistent Web Search Results with Bobble Xinyu Xing1 , Wei Meng1 , Dan Doozan1 , Nick- alization. We present the design and implementation of Bobble, a Web browser extension to other users, and expose any differences to the user--in real time. We present Bobble, a Chrome Web

  3. Neurobehavioral Syndromes in Cocaine-Exposed Newborn Infants.

    ERIC Educational Resources Information Center

    Lester, Barry M.; And Others

    1991-01-01

    The effects of fetal cocaine exposure on newborn cry characteristics were studied in 80 cocaine-exposed and 80 control infants. Findings were consistent with the notion that two neurobehavioral syndromes, excitable and depressed, can be described in cocaine-exposed infants and that these two syndromes are a result of direct neurotoxic effects and…

  4. CEREBELLAR HISTOGENESIS IN RATS EXPOSED TO 2450 MHZ MICROWAVE RADIATION

    EPA Science Inventory

    Pregnant rats were either exposed or sham exposed from day 13 of gestation until birth to 2450 MHz linearly polarized microwaves at 10 mW/sq cm. A third matching group served as cage control. After birth, the pups were kept with their mothers for 21 days without any treatment, an...

  5. Dust release from surfaces exposed to plasma T. M. Flanagana

    E-print Network

    Goree, John

    with plasma density, so that plasma cleaning is feasible at high plasma densities. ApplicationsDust release from surfaces exposed to plasma T. M. Flanagana and J. Goree Department of Physics exposed to plasma. In an experiment with a glass surface coated with lunar-simulant dust, it was found

  6. Re-analysis of Boston materials inventory. [Exposed structural surfaces

    SciTech Connect

    Daum, M.L.; Lipfert, F.W.

    1984-10-01

    In 1978 the Electric Power Research Institute (EPRI) contracted with TRC Environmental Consultants, Inc., to develop an inventory of exposed man-made (structural) surfaces in Boston. Previous studies have used production statistics and population distribution patterns to estimate the areal distribution of exposed materials. The EPRI/TRC inventory was designed to determine the validity of this approach by directly estimating quantities of exposed materials in a typical northeastern city, the Boston SMSA. Among its findings in the EPRI report, TRC noted that most materials are not uniformly distributed even at a neighborhood scale. Purpose of this reanalysis was to determine if the distributions and/or the amount of exposed materials as inventoried in the Boston area are related to some land use, demographic, or economic factors.

  7. TERATOGENESIS, TOXICITY, AND BIOCONCENTRATION IN FROGS EXPOSED TO DIELDRIN

    EPA Science Inventory

    Teratogenesis, acute and chronic toxicity, and bioconcentration were investigated in various like stages of African clawed frogs (Xenopus laevis), bullfrogs (Rana catesbeiana) and leopard frogs (Rana pipiens) exposed to aqueous dieldrin in static-renewal and continuous-flow tests...

  8. ENTERIC PARASITES IN WORKERS OCCUPATIONALLY EXPOSED TO SEWAGE

    EPA Science Inventory

    To determine if parasitic infections occur more frequently among workers exposed to wastewater than among controls, parasitologic examinations were performed on stool specimens collected over a 12-month period from sewer and highway maintenance workers. Three of 56 sewer maintena...

  9. 98. DETAIL VIEW OF STORM DAMAGE AND EXPOSED SUBSTRUCTURE, NORTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    98. DETAIL VIEW OF STORM DAMAGE AND EXPOSED SUBSTRUCTURE, NORTHWEST SIDE OF 4TH TEE, LOOKING WEST - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  10. 30. WAIALEIA STREAM CROSSING (30") LOOKING UPSTREAM. PIPE IS EXPOSED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. WAIALEIA STREAM CROSSING (30") LOOKING UPSTREAM. PIPE IS EXPOSED AT LEFT OF CONCRETE STRUCTURE. - Kalaupapa Water Supply System, Waikolu Valley to Kalaupapa Settlement, Island of Molokai, Kalaupapa, Kalawao County, HI

  11. RESPONSE OF MICROBIAL COMMUNITIES EXPOSED TO PENTACHLOROPHENOL IN ESTUARINE SEDIMENTS

    EPA Science Inventory

    Effects of environmental contaminants, including pentachlorophenol (PCP), a widely-used wood preserving agent, on estuarine microbial community composition and processes were evaluated. Slurries of estuarine sediments were exposed to PCP at environmentally relevant concentrations...

  12. PARATHION TOXICITY IN PERINATAL RATS EXPOSED IN UTERO

    EPA Science Inventory

    Adult pregnant female rats were exposed to subchronic doses of parathion throughout gestation and lactation. Their offspring were examined for possible toxicological effects. This study found that several physiological parameters were affected. Female perinates exhibited a signif...

  13. Immunofluorescence and morphology of Giardia lamblia cysts exposed to chlorine.

    PubMed Central

    Sauch, J F; Berman, D

    1991-01-01

    Giardia cyst-like objects detected by immunofluorescence in chlorinated water samples often cannot be positively identified by their morphological appearance. To determine the effect of chlorine on cyst immunofluorescence and morphology, Giardia lamblia cysts were exposed to chlorine for 48 h. The majority of cysts exposed to chlorine concentrations of 1 to 11 mg/liter at 5 and 15 degrees C lost their internal morphological characteristics necessary for identification, but most of them were still detectable by immunofluorescence. Images PMID:1854208

  14. Biological monitoring of workers exposed to N, N -dimethylformamide

    Microsoft Academic Search

    A. Casal Lareo; A. Perico; P. Bavazzano; C. Soave; L. Perbellini

    1995-01-01

    Some methods for analysing N,N-dimethylformamide and its metabolites [hydroxymethyl-N-methylformamide, hydroxymethylformamide and N-acetyl-S-(N-methylcarbamoyl)cysteine] in the urine of exposed workers are described. Unchanged dimethylformamide was measured after pretreatment of urine (2 ml) with silica gel cartridges and elution with methanol. The gas chromatographic analysis using a nitrogen phosphor detector made it possible to detect N,N-dimethylformamide in urine even when workers were exposed

  15. Partially exposed polymer dispersed liquid crystals for boundary layer investigations

    NASA Technical Reports Server (NTRS)

    Parmar, Devendra S.; Singh, Jag J.

    1992-01-01

    A new configuration termed partially exposed polymer dispersed liquid crystal in which the liquid crystal microdroplets dispersed in a rigid polymer matrix are partially entrapped on the free surface of the thin film deposited on a glass substrate is reported. Optical transmission characteristics of the partially exposed polymer dispersed liquid crystal thin film in response to an air flow induced shear stress field reveal its potential as a sensor for gas flow and boundary layer investigations.

  16. Ion bombardment of cometary ices analogues: production of organic samples for the EXPOSE-R2 mission on the International Space Station

    NASA Astrophysics Data System (ADS)

    Baratta, G. A.; Chaput, D.; Cottin, H.; Fernandez Cascales, L.; Palumbo, M. E.; Strazzulla, G.

    2014-04-01

    We describe the preparation and characterization (by UV-Vis-IR spectroscopy) of a set of organic samples, stable at room temperature and above, that are part of the experiment "Photochemistry on the Space Station (PSS)" planned to be enclosed in the EXPOSE-R2 mission, which will be conducted on the EXPOSE-R facility, outside the International Space Station (ISS).

  17. The AMINO experiment: methane photolysis under Solar VUV irradiation on the EXPOSE-R facility of the International Space Station

    NASA Astrophysics Data System (ADS)

    Carrasco, Nathalie; Cottin, Hervé; Cloix, Mégane; Jérome, Murielle; Bénilan, Yves; Coll, Patrice; Gazeau, Marie-Claire; Raulin, François; Saiagh, Kafila; Chaput, Didier

    2015-01-01

    The scientific aim of the present campaign is to study the whole chain of methane photo-degradation, as initiated by Solar vacuum-ultraviolet irradiation in Titan's atmosphere. For this purpose, the AMINO experiment on the EXPOSE-R mission has loaded closed cells for gas-phase photochemistry in space conditions. Two different gas mixtures have been exposed, named Titan 1 and Titan 2, involving both N2-CH4 gas mixtures, without and with CO2, respectively. CO2 is added as a source of reactive oxygen in the cells. The cell contents were analysed thanks to infrared absorption spectroscopy, gas chromatography and mass spectrometry. Methane consumption leads to the formation of saturated hydrocarbons, with no detectable influence of CO2. This successful campaign provides a first benchmark for characterizing the whole methane photochemical system in space conditions. A thin film of tholin-like compounds appears to form on the cell walls of the exposed cells.

  18. 30 CFR 817.13 - Casing and sealing of exposed underground openings: General requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Casing and sealing of exposed underground openings: General requirements. 817.13...Casing and sealing of exposed underground openings: General requirements. Each exploration...well, or other exposed underground opening shall be cased, lined, or...

  19. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...arresters, ungrounded and exposed power conductors and telephone wires. 77.508 ...arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be...

  20. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...arresters, ungrounded and exposed power conductors and telephone wires. 77.508 ...arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be...

  1. 30 CFR 75.521 - Lightning arresters; ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...arresters; ungrounded and exposed power conductors and telephone wires. 75.521 ...arresters; ungrounded and exposed power conductors and telephone wires. Each ungrounded, exposed power conductor and each ungrounded,...

  2. 30 CFR 75.521 - Lightning arresters; ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...arresters; ungrounded and exposed power conductors and telephone wires. 75.521 ...arresters; ungrounded and exposed power conductors and telephone wires. Each ungrounded, exposed power conductor and each ungrounded,...

  3. Factors Influencing the Intended Likelihood of Exposing Sexual Infidelity.

    PubMed

    Kruger, Daniel J; Fisher, Maryanne L; Fitzgerald, Carey J

    2015-08-01

    There is a considerable body of literature on infidelity within romantic relationships. However, there is a gap in the scientific literature on factors influencing the likelihood of uninvolved individuals exposing sexual infidelity. Therefore, we devised an exploratory study examining a wide range of potentially relevant factors. Based in part on evolutionary theory, we anticipated nine potential domains or types of influences on the likelihoods of exposing or protecting cheaters, including kinship, strong social alliances, financial support, previous relationship behaviors (including infidelity and abuse), potential relationship transitions, stronger sexual and emotional aspects of the extra-pair relationship, and disease risk. The pattern of results supported these predictions (N = 159 men, 328 women). In addition, there appeared to be a small positive bias for participants to report infidelity when provided with any additional information about the situation. Overall, this study contributes a broad initial description of factors influencing the predicted likelihood of exposing sexual infidelity and encourages further studies in this area. PMID:25663236

  4. Analysis of a space-exposed thermoplastic resin

    NASA Technical Reports Server (NTRS)

    Young, Philip R.; Slemp, Wayne S.; Siochi, Emilie J.; Davis, Judith R. J.

    1992-01-01

    The chemical characterization of a thermoplastic resin exposed to the low Earth orbit (LEO) environment for 10 months and for 5.8 years is reported. The resin, processed as a thick film and as a matrix for a graphite fiber reinforced composite, few exposed in the RAM direction on the NASA Long Duration Exposure Facility (LDEF). Differences attributable to environmental exposure were detected in infrared spectra and in various molecular weight parameters of film after 10 months in LEO. Those effects were not as apparent in composites after 5.8 years in LEO. Increased exposure to atomic oxygen toward the end of the LDEF mission probably scrubbed these effects from specimens exposed for 5.8 years. The intent of this study is to increase our fundamental understanding of space environmental effects on polymeric materials and to develop a benchmark for enhancing our methodology for and understanding of the ground-based simulation of space environmental effects.

  5. Decision support for subjects exposed to heat stress.

    PubMed

    Seeberg, Trine M; Vardøy, Astrid-Sofie B; Taklo, Maaike M Visser; Austad, Hanne Opsahl

    2013-03-01

    The physiological and activity strain index (PASI) has been developed to improve the online decision support for workers exposed to heat stress. Fire fighters (smoke divers) which are exposed to both heat-stress and high-risk situations have been used as test case. PASI combines a modified version of the relatively well-known physiological strain index (PSI) with activity data from accelerometers. The algorithm has been developed based on tests in a laboratory, and it has been verified in two field tests performed by smoke divers exposed to heat stress. The verification demonstrates that it is possible to distinguish between high- and low-risk situations when data from accelerometers are added to the situation analysis. This indicates that PASI can contribute to an improved risk assessment and online decision support for smoke divers compared to using PSI alone. PMID:24235112

  6. Cytogenetic damage in female Pakistani agricultural workers exposed to pesticides.

    PubMed

    Ali, Tayyaba; Bhalli, Javed A; Rana, Shahid M; Khan, Qaiser M

    2008-06-01

    Bhawalpur is a major cotton-growing area in Pakistan. Cotton picking in Pakistan is carried out by females and as a result of the intensive use of pesticides during the growing season these females are exposed to pesticide residues in the picking season. In the present study, peripheral blood was obtained from 69 cotton pickers and 69 unexposed females and used to assess the effect of pesticide exposure on genetic damage as well as on hepatic enzymes and serum cholinesterase. The subjects were of similar average age in workers and control groups (37.55 +/- 12.75 vs. 37.52 +/- 13.47, P > 0.05). Average exposure time of the picker females was 10.26 +/- 6.14 years. Subjects from the exposed group did not use any protective measures during their work activities. Levels of serum cholinesterase were lower, and levels of alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase were higher in the exposed workers as compared with the control group (P < 0.001). The exposed group exhibited significantly increased frequencies of binucleated cells with micronuclei (12.72 +/- 3.48 vs. 4.35 +/- 2.44, P < 0.001) and total number of micronuclei in binucleated lymphocytes (16.51 +/- 4.27 vs. 5.86 +/- 3.09, P < 0.001) in comparison with subjects of the control group. The binucleated cells with micronuclei frequency also seemed to increase with age in both the groups, however, the magnitude of increase was greater in exposed group than the control. Results from the present study indicate that occupational exposure to pesticide mixtures results in cytogenetic damage in exposed females. PMID:18418870

  7. Semen quality in workers exposed to 2-ethoxyethanol.

    PubMed Central

    Ratcliffe, J M; Schrader, S M; Clapp, D E; Halperin, W E; Turner, T W; Hornung, R W

    1989-01-01

    To evaluate whether long term exposure to 2-ethoxyethanol (2EE) may affect semen quality, a cross sectional study was conducted among men exposed to 2EE used as a binder slurry in a metal castings process. Full shift breathing zone exposures to 2EE ranged from non-detectable to 24 ppm (geometric mean 6.6 ppm). Because of the potential for substantial absorption of 2EE through skin exposure, urine measurements of the metabolite of 2EE, 2-ethoxyacetic acid (2EAA) were conducted, showing levels of 2EAA ranging from non-detectable to 163 mg 2EAA/g creatinine. Only 37 exposed men (50% participation) and 39 non-exposed comparison (26% participation) from elsewhere in the plant provided a sperm sample. A questionnaire to determine personal habits, and medical and work histories, and a physical examination of the urogenital tract were also administered. The average sperm count per ejaculate among the workers exposed to 2EE was significantly lower than that of the unexposed group (113 v 154 million sperm per ejaculate respectively; p = 0.05) after consideration of abstinence, sample age, subjects' age, tobacco, alcohol and caffeine use, urogenital disorders, fever, and other illnesses. The mean sperm concentrations of the exposed and unexposed groups did not significantly differ from each other (44 and 53 million/ml respectively). No effect of exposure to 2EE on semen volume, sperm viability, motility, velocity, and normal morphology or testicular volume was detected, although some differences in the proportion of abnormal sperm shapes were observed. These data suggest that there may be an effect of 2EE on sperm count among these workers, although the possibility that other factors may be affecting the semen quality in both exposed and unexposed men in this population or that the results reflect bias introduced by the low participation rates cannot be excluded. PMID:2818974

  8. The EXPOSE-E Mission on the ISS

    NASA Astrophysics Data System (ADS)

    Rabbow, Elke; Rettberg, Petra; Panitz, Corinna; Reitz, Guenther

    The International Space Station ISS provides a variety of external research platforms for ex-periments aiming at the utilization of space parameters like vacuum, temperature oscillation, extraterrestrial UV and ionizing radiation. For 1.5 years the astrobiological experimental ESA facility EXPOSE-E was accommodated on the EuTEF Platform on one of the external balconies of the Columbus Module with 5 exobio-logical and 3 radiation experiments, exposing the chemical, biological and dosimetric samples to the harsh space environment. The main interest of the experiments was to increase our knowledge on the origin, evolution and distribution of life, on Earth and possibly beyond. The biological experiments investigated resistance and adaptation of organisms like bacteria, Achaea, fungi, lichens and plant seeds to extreme environmental conditions and underlying mechanisms like DNA repair. The organic chemical experiments analyse chemical reactions triggered by the extraterrestrial environment, especially short wavelength UV radiation, to better understand prebiotic chemistry. The facility is optimized to allow exposure of biologi-cal specimen and material samples under a variety of conditions, using optical filter systems. Environmental parameters like temperature and radiation were regularly recorded and down linked by telemetry. The exposure facility EXPOSE-E itself and the accommodated experiments and samples are introduced. A complete Mission overview of this recent long term astrobiological experiment is presented: from the sample preparation and launch to the landing and sample retrieval. Mission data and an assessment of the impacting space parameters during the mission are given. After EXPOSE-E, the sister facility EXPOSE-R was launched and still is in space. A short status information and outlook on this second astrobiological Mission will be included.

  9. Serum prolactin in subjects occupationally exposed to manganese.

    PubMed

    Mutti, A; Bergamaschi, E; Alinovi, R; Lucchini, R; Vettori, M V; Franchini, I

    1996-01-01

    To evaluate whether or not occupational exposure to manganese (Mn) affects basal levels of serum prolactin (PRL), a cross-sectional study was carried out in 31 occupationally-exposed workers, aged 39.2 years (DS 7.9) exposed to manganese (Mn) dusts for 14.5 years (range: 5 to 29 years) in a ferroalloy producing plant. Thirty-four industrial workers not exposed to neurotoxic chemicals and of comparable age composed the control group. Airborne Mn concentrations in dusts of the furnace area ranged 210 to 980 micrograms/m3, which is below the current American Conference of Governmental Industrial Hygienists (ACGIH)-recommended threshold limit value-time weighted average (TLV-TWA) of 1 mg/m3. Manganese concentrations in blood Mn (MnB) and in urine (MnU) were significantly higher in Mn-exposed workers as compared to control workers. The Mn-exposed workers showed significantly higher serum prolactin (PRL) levels with the geometric mean (GM) being 9.77 ng/ml with a geometric standard deviation (GSD) of 1.69 as compared to controls (GM 4.65 ng/ml, GSD 1.78, p < 0.001). Serum PRL was negatively related to age and positively correlated with both MnB and MnU. Dose-effect relationships were still significant in partial correlation analysis after control for age. The prevalence of abnormally high PRL values was consistent with a dose-response relationship. The observed increase in serum PRL among Mn-exposed workers suggests an impairment of tonic inhibition by tubero-infundibular dopaminergic neurons. The correlation between PRL and both MnB and MnU in samples collected at least 48 h from the last exposure suggests that such indices provide an estimation of the target dose. PMID:8834356

  10. Survival of Spores of Trichoderma longibrachiatum in Space: data from the Space Experiment SPORES on EXPOSE-R

    NASA Astrophysics Data System (ADS)

    Neuberger, Katja; Lux-Endrich, Astrid; Panitz, Corinna

    2015-01-01

    In the space experiment `Spores in artificial meteorites' (SPORES), spores of the fungus Trichoderma longibrachiatum were exposed to low-Earth orbit for nearly 2 years on board the EXPOSE-R facility outside of the International Space Station. The environmental conditions tested in space were: space vacuum at 10-7-10-4 Pa or argon atmosphere at 105 Pa as inert gas atmosphere, solar extraterrestrial ultraviolet (UV) radiation at ? > 110 nm or ? > 200 nm with fluences up to 5.8 × 108 J m-2, cosmic radiation of a total dose range from 225 to 320 mGy, and temperature fluctuations from -25 to +50°C, applied isolated or in combination. Comparable control experiments were performed on ground. After retrieval, viability of spores was analysed by two methods: (i) ethidium bromide staining and (ii) test of germination capability. About 30% of the spores in vacuum survived the space travel, if shielded against insolation. However, in most cases no significant decrease was observed for spores exposed in addition to the full spectrum of solar UV irradiation. As the spores were exposed in clusters, the outer layers of spores may have shielded the inner part. The results give some information about the likelihood of lithopanspermia, the natural transfer of micro-organisms between planets. In addition to the parameters of outer space, sojourn time in space seems to be one of the limiting parameters.

  11. Study of indium tin oxide films exposed to atomic axygen

    NASA Technical Reports Server (NTRS)

    Snyder, Paul G.; De, Bhola N.; Woollam, John A.; Coutts, T. J.; Li, X.

    1989-01-01

    A qualitative simulation of the effects of atomic oxygen has been conducted on indium tin oxide (ITO) films prepared by dc sputtering onto room-temperature substrates, by exposing them to an RF-excited oxygen plasma and characterizing the resulting changes in optical, electrical, and structural properties as functions of exposure time with ellipsometry, spectrophotometry, resistivity, and X-ray measurements. While the films thus exposed exhibit reduced resistivity and optical transmission; both of these effects, as well as partial crystallization of the films, may be due to sample heating by the plasma. Film resistivity is found to stabilize after a period of exposure.

  12. [Radiological observation on the workers exposed to vanadium].

    PubMed

    Huang, R T

    1989-09-01

    The roentgenologic findings of 76 workers exposed to vanadium were presented. The chest X-ray showed increase in lung markings in 58 cases, diffuse streaks and reticular shadows in 15 cases, interstitial pulmonary fibrosis. The clinical features of the 71 workers were as follows: 63 cases had coughs, 53 cases had coughs with expectorations, 27 cases showed difficulty in breathing, and 31 cases had wheezing or whistling sounds in the lungs. The workers were exposed to vanadium pentoxide fume at concentration ranging from 1.2 to 18 mg/m3 and dust from 1.27 to 27.7 mg/m3. PMID:2625063

  13. Fibrin sealant-assisted revision of the exposed Ahmed tube.

    PubMed

    Choudhari, Nikhil S; Neog, Aditya; Latka, Supriya; Srinivasan, Bhaskar

    2015-01-01

    Tube exposure is a known complication of Ahmed glaucoma valve (AGV) implantation. Repair of the exposed tube is not easy. A 42-year-old monocular aphakic male had undergone retinal detachment repair with placement of an episcleral-encircling band followed by implantation of AGV. He presented to the clinic on routine review with exposure of the shunt tube. The complication was managed by placing scleral and conjunctival grafts over the exposed tube using a fibrin adhesive (Tisseel kit; Baxter AG, Vienna, Austria). The novel use of the fibrin sealant in the repair of AGV tube exposure was for better graft-integration. PMID:25624685

  14. Lung cancer in rats exposed to fibrogenic dusts

    SciTech Connect

    Holland, L.M.; Wilson, J.S.; Tillery, M.I.; Smith, D.M.

    1984-01-01

    Fischer-344 rats were exposed to quartz dusts and to quartz-bearing oil shale dusts in long-term inhalation studies. Aerosol concentrations of 12 mg/m/sup 3/ and 152-176 mg/m/sup 3/ for quartz and shale dusts, respectively, were used in exposure regimens lasting up to two years. Pulmonary fibrosis was observed in most animals surviving beyond 400 days. Adenocarcinomas and epidermoid carcinomas of the lung were observed in animals from all exposure groups, including those exposed to quartz alone. The pulmonary tumors were a late effect, with the earliest lung tumor being observed after 651 days. 13 references, 10 figures, 4 tables.

  15. Organic samples produced by ion bombardment of ices for the EXPOSE-R2 mission on the International Space Station

    NASA Astrophysics Data System (ADS)

    Baratta, G.; Chaput, D.; Cottin, H.; Fernandez Cascales, L.; Palumbo, M.; Strazzulla, G.

    2014-07-01

    We describe the preparation and characterization (by UV-Vis-IR spectroscopy) of a set of organic samples, stable at room temperature and above, that are part of the experiment "Photochemistry on the Space Station (PSS)" planned to be enclosed in the EXPOSE-R2 mission, which will be conducted on the EXPOSE-R facility, outside the International Space Station (ISS). The organic materials are prepared in the Catania laboratory after 200 keV He+ irradiation of icy mixtures, namely N_2:CH_4:CO deposited at 16 K on MgF_2 windows furnished by European Space Agency. It is widely accepted that such kind of materials produced by energetic processing are representative of organic material in astrophysical environments such as, e.g., comets. Once expelled from comets these materials are exposed to solar radiation during their interplanetary journey before they eventually land on the Earth and other planetary objects where they might give a contribution to the chemical and pre-biotical evolution. In particular our residues contain different chemical groups, including triple CN bonds that are considered relevant to pre-biotic chemistry (e.g. Palumbo et al., 2000). Therefore the samples will be exposed, for several months, to the solar ultraviolet photons that are a major source of energy to initiate chemical evolution in the Solar System. This will allow analysis of their destruction and evaluation of their lifetime in the interplanetary medium. The samples have three different thicknesses (about 200, 130, 65 nm) that will allow the estimation of the depth profile of destruction (e.g., Baratta et al., 2002). This experiment overcomes the limits of ground tests which do not reproduce exactly the space parameters.

  16. Charging time for dust grain on surface exposed to plasma

    SciTech Connect

    Sheridan, T. E. [Department of Physics and Astronomy, Ohio Northern University, Ada, Ohio 45810 (United States)

    2013-04-14

    We consider the charging of a dust grain sitting on a surface exposed to plasma. The stochastic model of Sheridan and Hayes [Appl. Phys. Lett. 98, 091501 (2011)] is solved analytically for the charging time, which is found to be directly proportional to the square root of the electron temperature and inversely proportional to both the grain radius and plasma density.

  17. Charging time for dust grain on surface exposed to plasma

    NASA Astrophysics Data System (ADS)

    Sheridan, T. E.

    2013-04-01

    We consider the charging of a dust grain sitting on a surface exposed to plasma. The stochastic model of Sheridan and Hayes [Appl. Phys. Lett. 98, 091501 (2011)] is solved analytically for the charging time, which is found to be directly proportional to the square root of the electron temperature and inversely proportional to both the grain radius and plasma density.

  18. FLOW CYTOMETRY ANALYSIS OF WHITE TAILED DEER EXPOSED TO BVDV

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two groups of four deer each, 2 to 4 weeks in age, were exposed to one of two bovine viral diarrhea virus (BVDV) strains: type 1b or type 2a, originally isolated from two different whitetail deer in southeast South Dakota in the fall of 2003. Two control age-matched deer were also used. Flow cytomet...

  19. Embryo- and fetotoxicity of chromium in pregestationally exposed mice

    SciTech Connect

    Junaid, M.; Murthy, R.C.; Saxena, D.K. [Industrial Toxicology Research Centre, Lucknow (India)] [Industrial Toxicology Research Centre, Lucknow (India)

    1996-10-01

    Chromium, an essential element in the human body required for proper carbohydrate, protein, and fat metabolism, is reported to impair gestational development of offspring of workers chronically exposed to this metal in the work place. Workers in chromium based industries can be exposed to concentrations two orders of magnitude higher than the general population. Among the general population, residents living near chromate production sites may be exposed to high levels of chromium (VI) in air or to elevated levels (40 - 50,000 ppm) of chromium in effluents. Shmitova reported afterbirth and puerperal hemorrhages in women industrially exposed to this metal and observed high chromium levels in blood and urine of pregnant women and in fetal and cord blood. Chromium readily passes the placental barrier and reaches the growing fetus. Exposure of mice to chromium during various gestational periods resulted in embryo and fetotoxic effects. This study looks at the role of body chromium accumulated pregestationally on embryo and fetal development and its subsequent transfer to feto-placental sites. 25 refs., 3 tabs.

  20. REPRODUCTIVE DEVELOPMENT IN MALE DEER MICE EXPOSED TO AGGRESSIVE BEHAVIOR

    EPA Science Inventory

    Male deer mice (Peromyscus maniculatus bairdii) were reared in a long photoperiod and housed individually from 3 weeks of age until they were killed 2, 4, or 6 weeks later. Males that were exposed to aggressive females for 2 min, three times per week, were of normal body weight a...

  1. 25. Interior detail view of women's waiting area, showing exposed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. Interior detail view of women's waiting area, showing exposed roof construction with lacquered finish, decorative cove molding at intersection of roof and walls, and interior framing details - Bend Railroad Depot, 1160 Northeast Divion Street (At foot of Kearny Street), Bend, Deschutes County, OR

  2. 24. VIEW OF NORTHWEST WALL IN ROOM 209, RESTROOM. EXPOSED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. VIEW OF NORTHWEST WALL IN ROOM 209, RESTROOM. EXPOSED BEAM RUNS ALONG NORTHWEST WALL. 3X3 LITE WINDOW IS IN THE NORTHEAST WALL. FLOOR TREATMENT IS WOOD, WALLS ARE GYPSUM BOARD. - Presidio of San Francisco, Cavalry Stables, Cowles Street, between Lincoln Boulevard & McDowell Street, San Francisco, San Francisco County, CA

  3. Airway hyperresponsiveness in cigarette smoke-exposed rats

    Microsoft Academic Search

    L. J. Xu; R. J. Dandurand; M. Lei; D. H. Eidelman

    1993-01-01

    To investigate the possibility that altered airway-parenchymal interaction may account for bronchial hyperresponsiveness induced by cigarette smoke exposure, we tested the effect of administration of cigarette smoke (SM), elastase (EL), and both SM and EL on airway responsiveness in 41 Long-Evans male rats. Twelve were exposed to 30 puffs of SM for 15 weeks; 8 received a single intratracheal injection

  4. 43. Interior view, east study window from the parlor. Exposed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    43. Interior view, east study window from the parlor. Exposed areas above and to the left of the window show remnants of decorative painting believed to date from early in the nineteenth century. - John Bartram House & Garden, House, 54th Street & Lindbergh Boulevard, Philadelphia, Philadelphia County, PA

  5. Semen study of papaya workers exposed to ethylene dibromide

    SciTech Connect

    Ratcliffe, J.M.; Schrader, S.M.; Steenland, K.; Clapp, D.; Turner, T.

    1984-01-01

    A cross sectional semen and cytogenetic study was performed on male workers exposed to ethylene-dibromide (EDB) in the papaya fumigation industry in Hawaii. Semen analyses were conducted on 46 men in six fumigation facilities with an average length of employment of 5 years and airborne exposures to EDB ranging from 16 to 213 parts per billion. Statistically significant decreases in sperm count per ejaculate and the percentage of viable and motile sperm and increases in the proportion of specific morphological abnormalities were observed among exposed men when compared with controls. Semen volume and sperm concentration were also lower in the exposed group. No effect of exposure to EDB on sperm velocity, the overall proportion of sperm with normal morphology or YFF bodies was noted. The authors conclude that based on the decreases in sperm count, viability and motility and increases in certain types of morphological abnormalities among workers exposed to EDB, EDB may increase the risk of reproductive impairment in workers at exposure levels near the NIOSH recommended limit of 45 parts per billion and far below the current OSHA standard of 20 parts per million.

  6. Proteomic Profiling of Bladders from Mice Exposed with Sodium Arsenite

    EPA Science Inventory

    Arsenic, an environmental contaminant, has been linked with cancer of the bladder in humans. To study the mode of action of arsenic, female CH3 mice were exposed to 85 ppm sodium arsenite in their drinking water for 30 days. Following the exposure a comparative proteomic analysis...

  7. 12. A LONG RUN OF EXPOSED TOP SURFACE, NORTH TRAINING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. A LONG RUN OF EXPOSED TOP SURFACE, NORTH TRAINING WALL, ABOUT 1,500 FEET EAST OF THE FEDERAL CHANNEL MOUTH. VIEW TO WEST, TOWARD SAN FRANCISCO. - Oakland Harbor Training Walls, Mouth of Federal Channel to Inner Harbor, Oakland, Alameda County, CA

  8. Exposing Digital Forgeries From 3-D Lighting Environments

    E-print Network

    Farid, Hany

    Exposing Digital Forgeries From 3-D Lighting Environments Eric Kee 1 , Hany Farid 2 Department be estimated. Because 3-D surface normals usually cannot be determined from a single image, only the 2-D-parameter spherical harmonic model. Because 3-D surface normals usually cannot be determined from a single image, we

  9. A pill to treat people exposed to radioactive materials

    ScienceCinema

    Abergel, Rebecca

    2014-06-24

    Berkeley Lab's Rebecca Abergel discusses "A pill to treat people exposed to radioactive materials" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas. Go here to watch the entire event with all 8 speakers:

  10. The cocaine-exposed infant, Part I: Identification and assessment.

    PubMed

    Forrest, D C

    1994-01-01

    The incidence of cocaine use among women of childbearing years is rapidly increasing. The identification and assessment of the cocaine-exposed infant provides a challenge to the nurse practitioner. This article, the first of two parts, describes identification and assessment techniques. Part two will discuss intervention and teaching methods. PMID:8120778

  11. Energy-Exposed Instruction Set Architectures Krste Asanovic

    E-print Network

    Asanovic, Krste

    regis- ters, and pipeline control logic. Modern machine pipelines have been refined to the point where their performance effects can be hidden, there is no incentive to expose these constituent micro to deactivate unnecessary portions of the machine microarchitecture. We are initially focusing on integer

  12. Gibraltar: Exposing Hardware Devices to Web Pages Using AJAX

    Microsoft Academic Search

    Kaisen Lin; David Chu; James Mickens; Li Zhuang; Feng Zhao; Jian Qiu

    2012-01-01

    Gibraltar is a new framework for exposing hardware devices to web pages. Gibraltar's fundamental insight is that JavaScript's AJAX facility can be used as a hardware access protocol. Instead of relying on the browser to mediate device interactions, Gibraltar sandboxes the browser and uses a small device server to handle hardware requests. The server uses native code to interact with

  13. WATER RELATIONS OF DIFFERENTIALLY IRRIGATED COTTON EXPOSED TO OZONE

    EPA Science Inventory

    This field study was conducted to test the hypothesis that plants chronically exposed to be sore susceptible to drought because typically inhibits root growth and increases shoot-root ratios implants. otton was grown in open-top chambers on Hanford coarse sandy loam in Riverside,...

  14. 3. First floor of rear ell: view of exposed framing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. First floor of rear ell: view of exposed framing on north wall, floor, and ceiling, looking north - McCrone House, Rear Ell, New Castle Hundred, 1 mile South of intersection of U.S. Route 13 & Route 40, west of Route 13, New Castle, New Castle County, DE

  15. Youth Exposed to Violence: The Role of Protective Factors

    ERIC Educational Resources Information Center

    Howard, Kimberly A. S.; Budge, Stephanie L.; McKay, Kevin M.

    2010-01-01

    Using a sample of 174 inner-city urban high school students, this study examined the degree to which family and peer support would moderate the negative impact of exposure to violence on academic performance, symptoms of distress, and persistence intentions. Over 94% of the students reported having been exposed to at least one form of community…

  16. Exposing Digital Forgeries in Interlaced and De-Interlaced Video

    E-print Network

    Farid, Hany

    number of video surveillance cameras are also giving rise to an enormous amount of video data1 Exposing Digital Forgeries in Interlaced and De-Interlaced Video Weihong Wang, Student Member, IEEE, and Hany Farid, Member, IEEE Abstract With the advent of high-quality digital video cameras

  17. Exposing Digital Forgeries in Video by Detecting Duplication

    E-print Network

    Farid, Hany

    on a surveillance video, the characters in the movie Speed create a doctored video to conceal activity on the bus particularly in a video taken from a stationary surveillance camera. Given a video sequence, f(x, y, t), t [0Exposing Digital Forgeries in Video by Detecting Duplication Weihong Wang Department of Computer

  18. Exposing Digital Forgeries Through Specular Highlights on the Eye

    E-print Network

    Farid, Hany

    of digital tampering. Key words: Digital Tampering, Digital Forensics 1 Introduction The photograph in Fig. 1Exposing Digital Forgeries Through Specular Highlights on the Eye Micah K. Johnson and Hany Farid.cs.dartmouth.edu/{kimo,farid} Abstract. When creating a digital composite of two people, it is diffi- cult to exactly match the lighting

  19. Exposing Digital Forgeries by Detecting Inconsistencies in Lighting

    E-print Network

    Farid, Hany

    Descriptors I.4 [Image Processing]: Miscellaneous Keywords Digital Tampering, Digital Forensics 1Exposing Digital Forgeries by Detecting Inconsistencies in Lighting Micah K. Johnson Department a digital composite of, for example, two peo- ple standing side-by-side, it is often difficult to match

  20. Exposing Digital Forgeries in Video by Detecting Double Quantization

    E-print Network

    Farid, Hany

    Terms Security Keywords Digital Tampering, Digital Video Forensics 1. INTRODUCTION As a resultExposing Digital Forgeries in Video by Detecting Double Quantization Weihong Wang Department a technique for detecting double quantization in digital video that results from double MPEG compression

  1. Exposing Digital Forgeries Through Chromatic Aberration Micah K. Johnson

    E-print Network

    Farid, Hany

    Digital Tampering, Digital Forensics 1. INTRODUCTION Most images contain a variety of aberrationsExposing Digital Forgeries Through Chromatic Aberration Micah K. Johnson Department of Computer for automatically es- timating lateral chromatic aberration and show its efficacy in detecting digital tampering

  2. Exposing Digital Forgeries in Scientific Images Department of Computer Science

    E-print Network

    Farid, Hany

    Tampering, Digital Forensics 1. INTRODUCTION In 2004, Professor Hwang Woo-Suk and colleagues pub- lishedExposing Digital Forgeries in Scientific Images Hany Farid Department of Computer Science Dartmouth and Subject Descriptors I.4 [Image Processing]: Miscellaneous General Terms Security Keywords Digital

  3. Exposing Digital Forgeries from JPEG Ghosts Hany Farid, Member, IEEE

    E-print Network

    Farid, Hany

    -- Digital Forensics, Digital Tampering I. INTRODUCTION Recent advances in digital forensics have given rise1 Exposing Digital Forgeries from JPEG Ghosts Hany Farid, Member, IEEE Abstract-- When creating a digital forgery, it is often necessary to combine several images, for example, when compositing one person

  4. Selecting, Exposing and Defining a Soil Characterization Site

    NSDL National Science Digital Library

    The GLOBE Program, University Corporation for Atmospheric Research (UCAR)

    2003-08-01

    The purpose of this resource is to define a soil characterization site. The following factors are defined: location, latitude, longitude, elevation, aspect (the direction of the steepest slope across an exposed soil site) and landscape position and slope (describes the contours of the land at the soil characterization site).

  5. Dust release from surfaces exposed to plasma T. M. Flanagana)

    E-print Network

    Goree, John

    . The release rate increases with plasma density, so that plasma cleaning is feasible at high plasma densities has also been called plasma cleaning or shedding, is of interest in several fields including1 Dust release from surfaces exposed to plasma T. M. Flanagana) and J. Goree Department of Physics

  6. LINER MATERIALS EXPOSED TO TOXIC AND HAZARDOUS WASTES

    EPA Science Inventory

    This exploratory experimental research project was conducted (1975-1983) to assess the relative effectiveness and durability of a wide variety of liner materials when exposed to hazardous wastes under conditions that simulate different aspects of service in on-land waste storage ...

  7. LINER MATERIALS EXPOSED TO HAZARDOUS AND TOXIC WASTES

    EPA Science Inventory

    This exploratory experimental research project was conducted (1975-1983) to assess the relative effectiveness and durability of a wide variety of liner materials when exposed to hazardous wastes under conditions that simulate different aspects of service in on-land waste storage ...

  8. Research Article Decontamination of Surfaces Exposed to Carbon-Based

    E-print Network

    Vaziri, Ashkan

    Research Article Decontamination of Surfaces Exposed to Carbon-Based Nanotubes and Nanomaterials nanomaterial-specific decontamination guidelines. In this paper, we propose and investigate a potential method for surface decontamination of carbon-based nanomaterials using solvent cleaning and wipes. The results show

  9. Asthma in exercising children exposed to ozone: a cohort study

    Microsoft Academic Search

    Rob McConnell; Kiros Berhane; Frank Gilliland; Stephanie J London; Talat Islam; W James Gauderman; Edward Avol; Helene G Margolis; John M Peters

    2002-01-01

    Summary Background Little is known about the effect of exposure to air pollution during exercise or time spent outdoors on the development of asthma. We investigated the relation between newly-diagnosed asthma and team sports in a cohort of children exposed to different concentrations and mixtures of air pollutants. Methods 3535 children with no history of asthma were recruited from schools

  10. CUTICULAR LESIONS INDUCED IN GRASS SHRIMP EXPOSED TO HEXAVALENT CHROMIUM

    EPA Science Inventory

    Adult grass shrimp were exposed to four concentrations (0.5, 1.0, 2.0 and 4.0 ppm) of hexavalent chromium for 38 days. At the end of the exposure period, over 50% of the surviving shrimp possessed cuticular lesions that had many of the gross characteristics of 'shell disease.' Th...

  11. BEHAVIORAL AND AUTONOMIC THERMOREGULATION IN MICE EXPOSED TO MICROWAVE RADIATION

    EPA Science Inventory

    Preferred ambient temperature (T) and breathing rate were measured in free-moving mice exposed to 2,450-MHz microwaves. A waveguide-exposure system was imposed with a longitudinal temperature gradient that permitted mice to select their preferred T. Breathing rate was determined ...

  12. RESPONSE OF BUSH BEAN EXPOSED TO ACID MIST

    EPA Science Inventory

    Bush bean plants (Phaseolus vulgaris L. cv. Contender) were treated once a week for six weeks with simulated acid mist at five pH ranging from 5.5 to 2.0. Leaf injury developed on plants exposed to acid concentrations below pH 3 and many leaves developed a flecking symptom simila...

  13. Health Effects of Depleted Uranium on Exposed Gulf War Veterans

    Microsoft Academic Search

    Melissa A. McDiarmid; James P. Keogh; Frank J. Hooper; Kathleen McPhaul; Katherine Squibb; Robert Kane; Raymond DiPino; Michael Kabat; Bruce Kaup; Larry Anderson; Dennis Hoover; Lawrence Brown; Matthew Hamilton; David Jacobson-Kram; Belton Burrows; Mark Walsh

    2000-01-01

    A small group of Gulf War veterans possess retained fragments of depleted uranium (DU) shrapnel, the long-term health consequences of which are undetermined. We evaluated the clinical health effects of DU exposure in Gulf War veterans compared with nonexposed Gulf War veterans. History and follow-up medical examination were performed on 29 exposed veterans and 38 nonexposed veterans. Outcome measures employed

  14. Behavioural evaluation of workers exposed to mixtures of organic solvents.

    PubMed

    Maizlish, N A; Langolf, G D; Whitehead, L W; Fine, L J; Albers, J W; Goldberg, J; Smith, P

    1985-09-01

    Reports from Scandinavia have suggested behavioural impairment among long term workers exposed to solvents below regulatory standards. A cross sectional study of behavioural performance was conducted among printers and spray painters exposed to mixtures of organic solvents to replicate the Scandinavian studies and to examine dose-response relationships. Eligible subjects consisted of 640 hourly workers from four midwestern United States companies. Of these, 269 responded to requests to participate and 240 were selected for study based on restrictions for age, sex, education, and other potentially confounding variables. The subjects tested had been employed on average for six years. Each subject completed an occupational history, underwent a medical examination, and completed a battery of behavioural tests. These included the Fitts law psychomotor task, the Stroop colour-word test, the Sternberg short term memory scanning test, the short term memory span test, and the continuous recognition memory test. Solvent exposure for each subject was defined as an exposed or non-exposed category based on a plant industrial hygiene walk-through and the concentration of solvents based on an analysis of full shift personal air samples by gas chromatography. The first definition was used to maintain consistency with Scandinavian studies, but the second was considered to be more accurate. The average full shift solvent concentration was 302 ppm for the printing plant workers and 6-13 ppm for the workers at other plants. Isopropanol and hexane were the major components, compared with toluene in Scandinavian studies. Performance on behavioural tests was analysed using multiple linear regression with solvent concentration as an independent variable. Other relevant demographic variables were also considered for inclusion. No significant (p greater than 0.05) relation between solvent concentration and impairment on any of the 10 behavioural variables was observed after controlling for confounding variables. Exposed/non-exposed comparisons showed a significantly poorer digit span among those exposed, but this has not been generally reported in the Scandinavian studies. The medical examination showed no abnormalities of clinical significance. The inability to replicate the findings of the Scandinavian studies could have been due to the shortness of the duration of workers' exposure, the type of solvents in the mixtures, use of different behavioural tests, or to selection factors. PMID:3876109

  15. Amphetamine and stress responses in developmentally lead-exposed rats.

    PubMed

    Virgolini, Miriam B; Volosin, M; Fulginiti, A S; Cancela, L M

    2004-01-01

    In this study, pregnant Wistar dams were exposed to 220 ppm of lead (Pb) in drinking water during gestation and lactation. The response to the locomotor-stimulating effects of 0.5 mg/kg of amphetamine (AMPH) was evaluated in 35-day-old male offspring. The results demonstrated that developmental Pb exposure induced no differences in the response to the drug, although an increase in locomotor activity induced by a single saline (SAL) injection was observed selectively in the Pb-exposed group. Considering evidence that suggests a relationship between increased locomotor activity and stress response, a time course analysis of corticosterone (CS) secretion and locomotor performance was carried out. Higher basal levels of CS and elevated stress-induced secretion of this hormone in response to the injection were observed in Pb-exposed rats compared to controls, a pattern that showed a time-related increase in locomotor activity. Habituation to SAL injections prior to testing restored both CS secretion and locomotor response to SAL to levels comparable to controls and did not modify AMPH locomotor response measured in these new experimental conditions. Additionally, we demonstrated that these behavioral/hormonal disruptions were no longer detectable later in adulthood. Collectively, these data suggest that the stimulant-locomotor effect of AMPH in Pb-exposed rats is independent of the arousal of the animal at the time of its administration. They also support a unique profile of integrated behavioral and hormonal hyperresponsiveness in 35-day-old low-level Pb-exposed rats evidenced as hyperlocomotion and altered secretion of CS in response to an environmental manipulation, an effect that was no longer present later in life. PMID:15019963

  16. Mechanisms of gas precipitation in plasma-exposed tungsten

    SciTech Connect

    R. D. Kolasinski; D. F. Cowgill; D. C. Donovan; M. Shimada

    2012-05-01

    Precipitation in subsurface bubbles is a key process that governs how hydrogen isotopes migrate through and become trapped within plasma-exposed tungsten. We describe a continuum-scale model of hydrogen diffusion in plasma-exposed materials that includes the effects of precipitation. The model can account for bubble expansion via dislocation loop punching, using an accurate equation of state to determine the internal pressure. This information is used to predict amount of hydrogen trapped by bubbles, as well as the conditions where the bubbles become saturated. In an effort to validate the underlying assumptions, we compare our results with published positron annihilation and thermal desorption spectroscopy data, as well as our own measurements using the tritium plasma experiment (TPE).

  17. Temperature tolerance of nitrite-exposed channel catfish

    SciTech Connect

    Watenpaugh, D.E.; Beitinger, T.L.; Huey, D.W.

    1985-03-01

    Upper temperature tolerances of channel catfish Ictalurus punctatus were determined with the critical thermal maximum (CTM) method after fish were exposed to various sublethal concentrations of nitrite for 24 hours at 20/sup 0/C. The CTM was inversely related to nitrite concentration; group means ranged from 38.0/sup 0/C for controls to 35.9/sup 0/C for fish exposed to 1.4 mg NO/sub 2//L. As expected from previous studies, percent methemoglobin was correlated with nitrite concentration, and thus was inversely correlated with CTM. These results indicate that nitrite-temperature interactions have the potential of adversely affecting the productivity of high-density channel catfish aquaculture systems, particularly those located in the southern US during summer. 40 references, 1 table.

  18. Radiation effects on ETFE polymer exposed to glow discharge

    NASA Astrophysics Data System (ADS)

    Minamisawa, Renato Amaral; Abidzina, Volha; de Almeida, Adelaide; Budak, Satilmis; Tereshko, I.; Elkin, I.; Ila, Daryush

    2007-08-01

    The polymer ethylenetetrafluoroethylene (ETFE) is composed of alternating ethylene and tetrafluoroethylene segments. Because it has applications in areas such as medical physics and industrial coatings, there is a great interest in surface modification studies of ETFE polymer. When this material is exposed to ionizing radiation it suffers damage that depends on the type, energy and intensity of the irradiation. In order to determine the radiation damage mechanism from exposure to low voltage plasma, ETFE films were exposed to residual gas plasma in glow discharge regime to a fluence of 2 × 10 17 ions/cm 2. Irradiated films were analyzed with optical absorption photospectrometry, Fourier transform infrared (FTIR) and Raman spectroscopy to determine the chemical nature of the structural changes caused by low energy glow discharge.

  19. Skin friction measurement with partially exposed polymer dispersed liquid crystals

    NASA Technical Reports Server (NTRS)

    Parmar, D. S.; Holmes, H. K.

    1993-01-01

    Partially exposed polymer dispersed liquid crystal thin film (10-25 microns) deposited on a flat glass substrate has been used for the first time to measure skin friction. Utilizing the shear-stress-induced director reorientation in the partially exposed liquid-crystal droplets, optical transmission under crossed polarization has been measured as a function of the air flow differential pressure. Direct measurement of the skin friction with a skin friction drag balance, under the same aerodynamic conditions, lets us correlate the skin friction with optical transmission. This provides a unique technique for the direct measurement of skin friction from the transmitted light intensity. The results are in excellent agreement with the model suggested in this paper.

  20. Spores in artificial meteorites, the experiment SPORES on expose

    NASA Astrophysics Data System (ADS)

    Horneck, G.; Hock, B.; Wänke, H.; Rettberg, P.; Häder, D.-P.; Dachev, T.; Rabbow, E.; Reitz, G.; Panitz, C.; Lux-Endrich, A.; Richter, P.; Mishev, D.

    2002-11-01

    The experiment "Spores in artificial meteorites" (SPORES) will be accommodated in the EXPOSE facility outside of the Columbus module of the ISS. Spores of bacteria, fungi and ferns, which are especially adapted to survive extreme conditions, will be embedded in artificial meteorites and exposed to selected parameters of space. The experiment consists of the following three sub-units: (I) laminated structure where layers of meteorite material are sandwiched with biological layers, (II) intermixed structure with a layer of meteorite powder mixed with biological systems, and (III) monitoring of UV radiation and cosmic ionising radiation. After 3 years in space, the viability and impairment of the spores will be analysed in the laboratory using a set of biological and biochemical assays. The experiment will provide experimental clues to the question whether meteorite material offers enough protection against the harsh environment of space for spores to survive a long-term stay in space.

  1. Pneumoconiosis in animals exposed to poly(vinyl chloride) dust.

    PubMed Central

    Groth, D H; Lynch, D W; Moorman, W J; Stettler, L E; Lewis, T R; Wagner, W D; Kommineni, C

    1981-01-01

    Rats, guinea pigs and monkeys were exposed by inhalation (6 hr/day, 5 days/week) for up to 22 months to a 13 mg/m3 concentration of PVC dust. Autopsies on rats and guinea pigs were performed after 12 months of exposure and on monkeys after 22 months after 22 months of exposure. Lung function tests were performed on monkeys after 9, 14 and 22 months of exposure. Aggregates of alveolar macrophages containing PVC particles were found in the lungs of all animals. These aggregates were more numerous in the monkey lungs. No fibrosis or significant cellular infiltrates were present in or near these cellular aggregates. No significant effects on pulmonary function could be demonstrated in the monkeys exposed to PVC. Under the conditions of this experiment, inhaled PVC produced a benign pneumoconiosis. Images FIGURE 1. FIGURE 2. FIGURE 3. FIGURE 4. FIGURE 5. FIGURE 6. PMID:6800783

  2. A stream compiler for communication-exposed architectures

    Microsoft Academic Search

    Michael I. Gordon; William Thies; Michal Karczmarek; Jasper Lin; Ali S. Meli; Andrew A. Lamb; Chris Leger; Jeremy Wong; Henry Hoffmann; David Maze; Saman P. Amarasinghe

    2002-01-01

    With the increasing miniaturization of transistors, wire delays are becoming a dominant factor in microprocessor performance. To address this issue, a number of emerging architectures contain replicated processing units with software-exposed communication between one unit and another (e.g., Raw, SmartMemories, TRIPS). However, for their use to be widespread, it will be necessary to develop compiler technology that enables a portable,

  3. Hematological Changes in Fingerling Channel Catfish Exposed to Malachite Green

    Microsoft Academic Search

    John M. Grizzle

    1977-01-01

    Fingerling channel catfish (Ictalurus punctatus) were exposed to 0.1 mg\\/l malachite green in 40-liter aquariums (fasted fish) and 500-liter troughs (fed fish). In both tests, neutrophilia at 1 and 3 days after treatment was the most drastic hematological change found. Other significant changes (P < 0.05) in the test with fed fish were increases in erythrocyte counts, hemoglobin concentrations, and

  4. Light Timber-Framed Walls Exposed to Compartment Fires

    Microsoft Academic Search

    G. C. Thomas; A. H. Buchanan; A. J. Carr; C. M. Fleischmann; P. J. Moss

    1995-01-01

    The objective of this project was to determine the equivalent time of exposure (to the ISO-834 standard fire), for a number of light timber-framed wall assemblies exposed to a range of time temperature curves characteristic of compartment fires.This analysis considered only the thermal behavior of the walls. Load bearing performance will be the subject of the next phase of the

  5. Nail damage in spray operators exposed to paraquat

    Microsoft Academic Search

    C. E. D. Hearn; W. Keir

    1971-01-01

    Hearn, C. E. D., and Keir, W. (1971).Brit. J. industr. Med.,28, 399-403. Nail damage in spray operators exposed to paraquat. Nail damage in 55 persons due to contamination by diluted paraquat in a group of 296 spray operators employed on a sugar estate in Trinidad is described.The commonest lesion seen was transverse white bands of discoloration, but loss of nail

  6. Blood analysis of rabbits exposed to nitrogen monoxide

    SciTech Connect

    Sharrock, P.; Levy, P.; Massol, M.

    1984-01-01

    Rabbits exposed to NO-containing atmospheres develop an EPR signal in their blood which can be detected with good sensitivity following dithionite reduction and freezing to 160 K. The spectroscopic parameters indicate that NO is bound preferentially to the ..cap alpha.. chains of hemoglobin in the quaternary T state. The EPR signal intensity increases with time and with the concentration of NO but decreases rapidly (t/sub 1/2/ approx. = 15 min) when the rabbits are returned to clean air.

  7. Space Tribometers: Design for Exposed Experiments on Orbit

    Microsoft Academic Search

    Brandon A. Krick; W. Gregory Sawyer

    2011-01-01

    Eight pin-on-disk tribometers have been made for testing materials in space on board the International Space Station. They\\u000a will be exposed directly to the low earth orbit (LEO) environment on board the “Materials on the International Space Station\\u000a Experiments” platform where they will experience extreme conditions including atomic oxygen, ultrahigh vacuum, radiation (including\\u000a UV radiation), and thermal ranges from ?40

  8. Viscoelastic Properties of Vascular Endothelial Cells Exposed to Stretch

    E-print Network

    Kathryn Osterday; Thomas Chew; Phillip Loury; Jason Haga; Manuel Gomez-Gonzalez; Juan C. del Alamo; Shu Chien

    2013-09-10

    In this paper, we study how cytoskeletal remodeling is correlated to changes in subcellular microrheology. We analyze the changes in the magnitude and directionality of the shear and elastic moduli of bovine aortic endothelial cells (BAECs) exposed to cyclical, uniaxial stretch. We find that, when stretched, BAECs stiffen and align their softest direction of mechanical polarization perpendicular to stretch. We hypothesize that the response of VECs to stretch acts to minimize intracellular strain in response to stress.

  9. Viscoelastic Properties of Vascular Endothelial Cells Exposed to Stretch

    E-print Network

    Osterday, Kathryn; Loury, Phillip; Haga, Jason; Gomez-Gonzalez, Manuel; del Alamo, Juan C; Chien, Shu

    2013-01-01

    In this paper, we study how cytoskeletal remodeling is correlated to changes in subcellular microrheology. We analyze the changes in the magnitude and directionality of the shear and elastic moduli of bovine aortic endothelial cells (BAECs) exposed to cyclical, uniaxial stretch. We find that, when stretched, BAECs stiffen and align their softest direction of mechanical polarization perpendicular to stretch. We hypothesize that the response of VECs to stretch acts to minimize intracellular strain in response to stress.

  10. Turfgrass species response exposed to increasing rates of glyphosate application

    Microsoft Academic Search

    Y. Senem Su; L. Ozturk; I. Cakmak; H. Budak

    2009-01-01

    To investigate the response of nine turfgrass species exposed to increasing rates of glyphosate application, the dry matter production, visual leaf injury symptoms (e.g., chlorosis and necrosis) and the concentrations of shikimate and mineral nutrients were determined in shoots. The rates of foliar glyphosate application were 0%, 5% (1.58mM), and 20% (6.32mM) of the recommended application rate for weed control.

  11. Testicular Changes in Newborn Rats Exposed to Phototherapy

    Microsoft Academic Search

    H. Koç; H. Altunhan; A. Dilsiz; A. Kaymakçi; S. Duman; B. Oran; I. Erkul

    1999-01-01

    In this study we investigated the long-term effects of 72-h continuous phototherapy on the reproductive system of newborn\\u000a rats. The animals' weight, fertilization rates, and number of newborn and histopathological changes in the gonads in a normal\\u000a group not exposed to phototherapy and in the test animals were compared. At the age of 24 weeks there were no significant\\u000a differences

  12. Limits of spalling of fire-exposed concrete

    Microsoft Academic Search

    K. D. Hertz

    2003-01-01

    Spalling may be a violent effect to fire-exposed concrete destroying the entire cross-sections or reducing the load-bearing capacity of a construction substantially. Spalling must therefore be considered when designing a concrete construction for fire. The paper discusses the present knowledge on the nature of spalling, add the latest findings from the research of the author, and derives limits within which

  13. Acaricides for controlling ticks on cattle and the problem of acaricide resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toward the end of the nineteenth century a complex of problems related to ticks and tick-borne diseases of cattle created a demand for methods to control ticks and reduce losses of cattle. The discovery and use of arsenical solutions in dipping vats for treating cattle to protect them against ticks ...

  14. Mechanical properties of MDCK II cells exposed to gold nanorods

    PubMed Central

    Pietuch, Anna; Brückner, Bastian Rouven; Schneider, David; Tarantola, Marco; Rosman, Christina; Sönnichsen, Carsten

    2015-01-01

    Summary Background: The impact of gold nanoparticles on cell viability has been extensively studied in the past. Size, shape and surface functionalization including opsonization of gold particles ranging from a few nanometers to hundreds of nanometers are among the most crucial parameters that have been focussed on. Cytoxicity of nanomaterial has been assessed by common cytotoxicity assays targeting enzymatic activity such as LDH, MTT and ECIS. So far, however, less attention has been paid to the mechanical parameters of cells exposed to gold particles, which is an important reporter on the cellular response to external stimuli. Results: Mechanical properties of confluent MDCK II cells exposed to gold nanorods as a function of surface functionalization and concentration have been explored by atomic force microscopy and quartz crystal microbalance measurements in combination with fluorescence and dark-field microscopy. Conclusion: We found that cells exposed to CTAB coated gold nanorods display a concentration-dependent stiffening that cannot be explained by the presence of CTAB alone. The stiffening results presumably from endocytosis of particles removing excess membrane area from the cell’s surface. Another aspect could be the collapse of the plasma membrane on the actin cortex. Particles coated with PEG do not show a significant change in elastic properties. This observation is consistent with QCM measurements that show a considerable drop in frequency upon administration of CTAB coated rods suggesting an increase in acoustic load corresponding to a larger stiffness (storage modulus). PMID:25671166

  15. Increased gluconeogenesis in rats exposed to hyper-G stress

    NASA Technical Reports Server (NTRS)

    Daligcon, B. C.; Oyama, J.; Hannak, K.

    1985-01-01

    The effect of glucogenesis on the plasma glucose and liver glycogen of rats exposed to hyper-G stress is investigated. Twelve male Sprague-Dawley rats are injected with C-14 lactate, alanine, of glycerol, and six of the rats are exposed to 3.1 G for 0.25, 0.50, and 1.0 hr. The plasma glucose and liver glycogen of the centrifuged and noncentrifuged rats are analyzed. A significant increase in the C-14 incorporation of the substrate into the plasma glucose and liver glycogen is observed in the centrifuged rats. The injection of 5-methoxyindole-2-carboxylic acid, a gluconeogenesis inhibitor, results in a blocked increase in plasma glucose and liver glycogen. The role of epinephrine on the hyperglycemic and liver glycogen responses of centrifuged rats is studied. It is concluded that the initial increase in plasma glucose and liver glycogen in rats exposed to hyper-G stress is the result of an increased rate of gluconeogenesis.

  16. Risk management among benzene-exposed oil refinery workers.

    PubMed

    Tompa, Anna; Jakab, Mátyás G; Major, Jeno

    2005-01-01

    Ten benzene-exposed oil refinery workers were genotoxicologically monitored in an annual follow-up study between 1990 and 2003 and compared with 87 industrial and 26 matched controls. Each of the exposed subjects suffered from several intercurrent non-infectious diseases such as joint, rheumatic, gastric and dental problems, as well as kidney and liver dysfunctions. The structural chromosome aberration (CA) yields of the exposed donors suggested a dose-dependent response to the mean peak benzene concentrations in the ambient air. Sister chromatid exchange (SCE), high-frequency SCE, DNA repair, and cell proliferation data also indicated the presence of genotoxic exposure at the workplace. The results of the biological and genotoxicological monitoring indicated the need of intervention (primary prevention of occupational exposure-related chronic non-infectious diseases) including the introduction of zero tolerance of benzene emission, health control, and education with motivation to change life-styles. The decrease in CA frequencies considered as the most established genotoxicological effect markers indicated the positive changes due to the achieved zero tolerance at the workplaces. The results also demonstrated the effectiveness of a trilateral co-operation between the health services, the employer and the employee in order to reduce the risk of the exposure-related intercurrent non-infectious diseases and to prevent further deterioration of the health state of the workers. PMID:16325561

  17. [Urinary 1-OHP excretion of urban traffic exhausts exposed workers].

    PubMed

    Mazzotta, M; d'Ettorre, G; Cazzato, R G; De Giorgio, N

    2007-01-01

    The vehicles exhaust in the traffic represents an important contributing factor for common air pollutants inhalation. The aim of this study was to investigate, the possible correlation between occupational exposition to polycyclic aromatic hydrocarbons (PAHs) generated from incomplete combustion, by dosage of urinary 1-hydroxypyrene (1-OHP u) as biomarker of internal dose for polycyclic aromatic hydrocarbons. In the study were included 29 workers exposed to urban traffic exhausts and of 18 non exposed workers. In boths populations was considered the tobacco smoke exposition. The results showed that exposed had levels of 1-OHP u in end-of-shift samples generally higher than those in pre-shift samples and showed an association to tobacco smoke exposition. In the control population tobacco smoke exposition appeared associated to the highest levels of 1-OHP u. The study suggests that the occupational exposure to traffic exhausts is associated with increased urinary excretion of 1-OHP. In addition, by our results seems to be a correlation between high levels of 1-OHP in the urine and increased risk of PAHs inhalation. PMID:18409820

  18. Asthma, rhinitis, and dermatitis in workers exposed to reactive dyes.

    PubMed Central

    Nilsson, R; Nordlinder, R; Wass, U; Meding, B; Belin, L

    1993-01-01

    A survey was conducted at 15 textile plants with dyehouses in western Sweden. Employees with a history of work related rhinitis, asthma, or skin symptoms were offered a clinical and immunological investigation including skin prick tests, skin patch tests, and radioallergosorbent tests (RASTs) to detect specific allergy to reactive dyes. Among the 1142 employees, 162 were exposed to reactive dyes and 10 of these (6%) reported work related respiratory or nasal symptoms. An allergy to reactive dyes could be confirmed in five (3%, 95% confidence interval 1-7%). All but one had been exposed to reactive dyes for one year or less before the onset of symptoms. Positive RASTs could be detected in four of the five patients. All of the RAST positive patients were positive to remazol black B, but six out of eight additional remazol dyes also elicited positive results. RAST and RAST inhibition showed a cross reactivity between some of the dyes. Seven persons with work related dermatitis and three with urticaria or Quincke oedema were found. In one patient contact dermatitis to a monoazo dye was shown, but no positive patch test reactions to reactive dyes. IgE-mediated allergy to reactive dyes seems to be an important cause of respiratory and nasal symptoms among dyehouse employees exposed to dust from reactive dyes. PMID:8431393

  19. Analysis Of The Returned Samples From A Space Exposure Experiment: The ORGANIC Experiment on EXPOSE-R on the ISS

    NASA Astrophysics Data System (ADS)

    Bryson, Kathryn; Peeters, Zan; Salama, Farid; Foing, Bernard; Ehrenfreund, Pascale; Elsaesser, Andreas; Ricco, Antonio; Jessberger, Elmar K; Schmidt, Werner; Robert, François

    2014-06-01

    The ORGANIC experiment on the multi-user facility EXPOSE-R on the International Space Station investigated the chemical evolution, survival, destruction, and chemical modification of PAHs and fullerenes in space. Aromatic networks are among the most abundant organic material in space. PAHs and fullerenes have been identified in meteorites and are thought to be among the carriers for numerous astronomical absorption and emission features.Thin films of selected PAHs and fullerenes have been subjected to the low Earth orbit environment as part of the ORGANIC experiment.EXPOSE-R with its experiment inserts was mounted on the outside of the ISS for 682 days starting in 2009. The samples were returned to Earth and inspected in spring 2011. The period outside the ISS provided continuous exposure to the cosmic-, solar-, and trapped-particle radiation background and >2500 h of unshadowed solar illumination. All trays carry both solar-irradiation-exposed and dark samples shielded from the UV photons, enabling discrimination between the effects of exposure to solar photons and cosmic rays. The samples were analyzed before exposure to the space environment with UV-VIS and IR spectroscopy. Ground truth monitoring of additional sample carriers was performed through UV-VIS spectroscopy at regular intervals at NASA ARC (Bryson et al. 2011, Adv. Space Res. 48, 1980). The UV-VIS and IR spectroscopic measurements were collected for the returned flight samples.We report on the scientific experiment, the details of the ground control analysis, and returned flight sample results. We discuss how extended space exposure experiments allow to enhance our knowledge on the evolution of organic compounds in space.

  20. Long term health and neurodevelopment in children exposed to antiepileptic drugs before birth

    PubMed Central

    Dean, J; Hailey, H; Moore, S; Lloyd, D; Turnpenny, P; Little, J

    2002-01-01

    Objective: To investigate the frequency of neonatal and later childhood morbidity in children exposed to antiepileptic drugs in utero. Design: Retrospective population based study. Setting: Population of the Grampian region of Scotland. Participants: Mothers taking antiepileptic drugs in pregnancy between 1976 and 2000 were ascertained from hospital obstetric records and 149 (58% of those eligible) took part. They had 293 children whose health and neurodevelopment were assessed. Main outcome measures: Frequencies of neonatal withdrawal, congenital malformations, childhood onset medical problems, developmental delay, and behaviour disorders. Results: Neonatal withdrawal was seen in 20% of those exposed to antiepileptic drugs. Congenital malformations occurred in 14% of exposed pregnancies, compared with 5% of non-exposed sibs, and developmental delay in 24% of exposed children, compared with 11% of non-exposed sibs. After excluding cases with a family history of developmental delay, 19% of exposed children and 3% of non-exposed sibs had developmental delay, 31% of exposed children had either major malformations or developmental delay, 52% of exposed children had facial dysmorphism compared with 25% of those not exposed, 31% of exposed children had childhood medical problems (13% of non-exposed sibs), and 20% had behaviour disorders (5% of non-exposed). Conclusion: Prenatal antiepileptic drug exposure in the setting of maternal epilepsy is associated with developmental delay and later childhood morbidity in addition to congenital malformation. PMID:11950853

  1. Exposed-core chalcogenide microstructured optical fibers for chemical sensing

    NASA Astrophysics Data System (ADS)

    Troles, Johann; Toupin, Perrine; Brilland, Laurent; Boussard-Plédel, Catherine; Bureau, Bruno; Cui, Shuo; Mechin, David; Adam, Jean-Luc

    2013-05-01

    Chemical bonds of most of the molecules vibrate at a frequency corresponding to the near or mid infrared field. It is thus of a great interest to develop sensitive and portable devices for the detection of specific chemicals and biomolecules for various applications in health, the environment, national security and so on. Optical fibers define practical sensing tools. Chalcogenide glasses are known for their transparency in the infrared optical range and their ability to be drawn as fibers. They are consequently good candidates to be used in biological/chemical sensing. For that matter, in the past decade, chalcogenide glass fibers have been successfully implemented in evanescent wave spectroscopy experiments, for the detection of bio-chemical species in various fields of applications including microbiology and medicine, water pollution and CO2 detection. Different types of fiber can be used: single index fibers or microstructured fibers. Besides, in recent years a new configuration of microstructured fibers has been developed: microstructured exposed-core fibers. This design consists of an optical fiber with a suspended micron-scale core that is partially exposed to the external environment. This configuration has been chosen to elaborate, using the molding method, a chalcogenide fiber for chemical species detection. The sensitivity of this fiber to detect molecules such as propan-2-ol and acetone has been compared with those of single index fibers. Although evanescent wave absorption is inversely proportional to the fiber diameter, the result shows that an exposed-core fiber is much more sensitive than a single index fiber having a twice smaller external diameter.

  2. Induction of P-450 in workers exposed to dioxin.

    PubMed Central

    Halperin, W; Kalow, W; Sweeney, M H; Tang, B K; Fingerhut, M; Timpkins, B; Wille, K

    1995-01-01

    OBJECTIVES--To examine the effects of occupational exposure to substances contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on cytochrome P-4501A2 activity in a cross sectional medical survey. METHODS--The exposed workers had been employed at two chemical plants > 15 years earlier in the manufacture of 2,4, 5-trichlorophenol and its derivatives. The control group consisted of people with no occupational exposure to phenoxy herbicides and who lived within the communities of the exposed workers. A total of 58 workers and 125 unexposed controls participated in the analysis. Cytochrome P-450 activity was assessed with test that measures caffeine metabolites in the urine. A ratio of metabolites of caffeine (CMR) constituted a measure of P-4501A2 activity. RESULTS--Compared with the control group in multivariate logistic regression, raised non-significant associations were found for three of four categories of TCDD in exposed workers (TCDD < 20 pg/g, odds ratio (OR) 1.7, 95% confidence interval (95% CI) 0.6 to 5.0, TCDD 20-66, OR 0.3, 95% CI 0.0 to 1.7; TCDD 67-147, OR 2.3, 95% CI 0.6 to 8.8; TCDD > or = 148, OR 3.1, 95% CI 0.8 to 12.5). We found a strongly significant association of CMR and urinary cotinine, a measure of smoking, and urinary free ethanol. We found weak non-significant associations between P-4501A2 activity and increased serum TCDD among workers. CONCLUSIONS--The absence of an association between serum TCDD and cytochrome P-4501A2 may be due to the size of the study, insensitivity of the CMR to assess cytochrome P-4501A2 activity, or inadequate levels of exposure, although these were among the highest in human groups tested. PMID:7757172

  3. Petroleum films exposed to sunlight produce hydroxyl radical.

    PubMed

    Ray, Phoebe Z; Tarr, Matthew A

    2014-05-01

    Sunlight exposed oil films on seawater or pure water produced substantial amounts of hydroxyl radical as a result of irradiation. Oil was collected from the surface of the Gulf of Mexico following the Deepwater Horizon spill and exposed to simulated sunlight in thin films over water. Photochemical production of hydroxyl radical was measured with benzoic acid as a selective chemical probe in the aqueous layer. Total hydroxyl radical formation was studied using high benzoic acid concentrations and varying exposure time. The total amount of hydroxyl radical produced in 24 h irradiations of thin oil films over Gulf of Mexico water and pure water were 3.7×10(-7) and 4.2×10(-7) moles respectively. Steady state concentrations of hydroxyl radical were measured using a competition kinetics approach. Hydroxyl radical concentrations of 1.2×10(-16) to 2.4×10(-16) M were observed for seawater and pure water under oil films. Titanium dioxide (TiO2) nanomaterials were added to the system in an effort to determine if the photocatalyst would enhance oil photodegradation. The addition of TiO2 nanoparticles dramatically changed the observed formation rate of hydroxyl radical in the systems with NP water at pH 3, showing increased formation rate in many cases. With photocatalyst, the steady state concentration of radical decreased, predominantly due to an increase in the hydroxyl radical scavenging rate with oxide present. This study illustrates that oil is a strong and important source of hydroxyl radical when exposed to sunlight. The fate of oil and other dissolved species following oil spills will be heavily dependent on the formation and fate of hydroxyl radical. PMID:24405967

  4. Genetic damage in wood dust-exposed workers.

    PubMed

    Rekhadevi, P V; Mahboob, M; Rahman, M F; Grover, Paramjit

    2009-01-01

    Exposure to wood dust is common in carpentry workshops. Wood dust is known to be a human carcinogen, with a very high relative risk of adenocarcinoma of the nasal cavities and paranasal sinuses. The goal of this investigation was to conduct genotoxicity monitoring of carpenters involved in wooden furniture industry in order to test possible wood dust-induced genotoxic effects due to occupational exposure. The level of genetic damage was determined by comet, micronucleus and chromosomal aberration (CA) assays in peripheral blood lymphocytes (PBL) of 60 carpentry workers. In addition, the micronucleus test in buccal epithelial cells was carried out in the same subjects. Total antioxidant enzyme activities were measured by the indices: superoxide dismutase, glutathione peroxidase and catalase. A group of 60 non-exposed subjects matched by age, smoking and alcohol consumption habits were chosen as controls. The effect of age, smoking, alcohol consumption and duration of exposure was also analysed in the subjects of the present study. The results showed a statistically significant increase in mean DNA damage by comet assay, micronuclei frequency in buccal cells as well as PBL and frequency of CA in the exposed workers when compared to controls (P < 0.05). Analysis of the data showed that all the confounding factors had a significant effect on DNA damage and micronucleus frequency in buccal epithelial cells and PBL. Smoking and alcohol consumption did not have any significant effect by chromosomal aberration test. Antioxidant enzyme levels significantly decreased in the exposed subjects. Our findings indicate enhanced levels of genotoxicity in carpenters. Hence, these workers may have an increased cancer risk. PMID:18815121

  5. Study of electronic transport in gamma ray exposed nanowires

    SciTech Connect

    Gehlawat, Devender, E-mail: gehlawatd@yahoo.com; Chauhan, R.P.

    2014-01-01

    Graphical abstract: A sharp decline in the I–V characteristics of Cu (and Cd) nanowires was experimentally observed after the gamma ray exposure of nanowires. Irradiation induced transformations in the granular properties and the resonance state of electron–phonon coupling beyond a particular value of external field may be accountable for observed shape of I–V characteristics in gamma ray exposed nanowires. - Highlights: • Cu and Cd nanowires were synthesized by technique of electrodeposition in templates. • The nanowires were exposed to different doses of gamma ray photons. • A sharp decline in the current in I–V characteristics (IVC) was observed. • Structural deviation in terms of granular orientations was also analysed. • The electron–phonon coupling may be responsible for observed sharp decline in IVC. - Abstract: One dimensional nanostructures provide the most restricted and narrow channel for the transport of charge carriers and therefore 1D structures preserve their significance from the viewpoint of electronic devices. The net radiation effect on nanomaterials is expected to be more (due to their increased reactivity and lesser bulk volume) than their bulk counterparts. Radiation often modifies the structure and simultaneously the other physical properties of materials. In this manner, the irradiation phenomenon could be counted as a strong criterion to induce changes in the structural and electrical properties of nanowires. We have studied the effect of gamma rays on the electronic flow through Cu and Cd nanowires by plotting their I–V characteristics (IVC). The IVC of gamma ray exposed nanowires was found to be a combination of the linear and nonlinear regions and a decreasing pattern in the electrical conductivity (calculated from the linear portion of IVC) was observed as we increased the dose of gamma rays.

  6. Relative Efficiency Of TLD-100 Exposed to X-Rays

    SciTech Connect

    Ixquiac-Cabrera, J. M.; Gamboa-de Buen, I. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A.P. 70-543, Mexico 04510 DF (Mexico); Avila, O. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Mexico 11801 DF (Mexico); Brandan, M. E. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, A.P. 20-364, Mexico 01000 DF (Mexico)

    2008-08-11

    The relative efficiency of TLD-100 (LiF:Mg,Ti) exposed to X-rays in the range from 30 to 250 kV, with respect to {sup 60}CO gamma rays has been measured. Glow curves were deconvoluted into peaks 3 to 9. All efficiencies were greater than 1 having a maximum of 1.38 for the dosimetric region (peaks 3+4+5) and peaks 4, 5 and 9, and 2.2 for peaks 6a, 6b, 7 and 8 at the effective energy of 24 keV.

  7. Exposed water ice discovered near the south pole of Mars.

    PubMed

    Titus, Timothy N; Kieffer, Hugh H; Christensen, Phillip R

    2003-02-14

    The Mars Odyssey Thermal Emission Imaging System (THEMIS) has discovered water ice exposed near the edge of Mars' southern perennial polar cap. The surface H2O ice was first observed by THEMIS as a region that was cooler than expected for dry soil at that latitude during the summer season. Diurnal and seasonal temperature trends derived from Mars Global Surveyor Thermal Emission Spectrometer observations indicate that there is H2O ice at the surface. Viking observations, and the few other relevant THEMIS observations, indicate that surface H2O ice may be widespread around and under the perennial CO2 cap. PMID:12471268

  8. Dermatitis in workers exposed to antimony in a melting process.

    PubMed

    White, G P; Mathias, C G; Davin, J S

    1993-04-01

    An employee at a brazing rod manufacturing plant developed a generalized eruption of follicular papules and pustules. His job tasks included breaking up antimony ingots and melting the pieces in a crucible; he was exposed to antimony metal dust and to antimony trioxide fumes. Two fellow employees who later performed the same job tasks developed similar eruptions. The clinical and workplace evaluations suggested that the fumes from melting antimony were the cause of the dermatoses, and that the current Occupational Safety and Health Administration permissible exposure limit is not adequate to prevent cutaneous effects of antimony exposure. PMID:8487117

  9. Relative Efficiency Of TLD-100 Exposed to X-Rays

    NASA Astrophysics Data System (ADS)

    Ixquiac-Cabrera, J. M.; Gamboa-de Buen, I.; Ávila, O.; Brandan, M. E.

    2008-08-01

    The relative efficiency of TLD-100 (LiF:Mg,Ti) exposed to X-rays in the range from 30 to 250 kV, with respect to 60CO gamma rays has been measured. Glow curves were deconvoluted into peaks 3 to 9. All efficiencies were greater than 1 having a maximum of 1.38 for the dosimetric region (peaks 3+4+5) and peaks 4, 5 and 9, and 2.2 for peaks 6a, 6b, 7 and 8 at the effective energy of 24 keV

  10. Susuk - Black Magic Exposed “White” by Dental Radiographs

    PubMed Central

    Mohammed, Faraz

    2014-01-01

    Susuk or charm needles are a facial cum body art widely practiced among women of Malaysia, Brunei, Singapore, Thailand and Indonesia. These are small, needle-shaped metallic talismans inserted subcutaneously in different parts of the body. The concealed art of susuk was “exposed” by routine radiographic examination in the oral and maxillofacial region. This paper reports two such cases of unusual incidental radiographic finding in dental radiographs which were taken on a routine basis as part of the diagnostic work up. This article will also primarily enlighten the importance of radiographs in detecting such charm needles as the wearer keeps the body art a “hidden secret” thereby avoiding misdiagnosis. PMID:25177646

  11. [Benign pleural effusion in a carpenter exposed to asbestos].

    PubMed

    Petersen, Rolf; Pedersen, Carsten Franck; Munch, Erik Peter

    2010-10-25

    A 55-year-old carpenter developed pleurisy with pleural effusion on the right side in 2000 and on the left side in 2003. No known causes of pleurisy were found. He had been occupationally exposed to asbestos during a 6-month-period in 1971 while working with roof sheets made of asbestos cement. In the literature there is evidence of asbestos being a cause of benign pleural effusion. We found it likely that the pleurisy with pleural effusion found in this patient was an occupational condition and it should therefore be notified as industrial injury. PMID:21040677

  12. Erosion of graphite surface exposed to hot supersonic hydrogen gas

    NASA Technical Reports Server (NTRS)

    Sharma, O. P.

    1972-01-01

    A theoretical model based on laminar boundary layer flow equations is developed to predict the erosion rate of a graphite (AGCarb-101) surface exposed to a hot supersonic stream of hydrogen gas. The supersonic flow in the nozzle outside the boundary layer formed over the surface of the specimen is determined by assuming one-dimensional isentropic conditions. An overall surface reaction rate expression based on the experimental studies by Clarke and Fox is used to describe the interaction of hydrogen with graphite. A satisfactory agreement is found between the results of the computation, and the available experimental data. Some shortcomings of the model, and further possible improvements are discussed.

  13. Assimilation of 3H in photosynthesizing leaves exposed to HTO.

    PubMed

    Guenot, J; Belot, Y

    1984-12-01

    Potato and wine grape plants were exposed for a period of 4 h to tritiated water vapor, and simultaneously to 14CO2 which served as a tracer for photosynthetic assimilation. During and after exposure, foliar samples were collected in which the exchangeable and nonexchangeable fractions of organic 3H were determined, taking care that the exchangeable fraction should not be lost to atmosphere. It was demonstrated that about 20% of the organic H in vegetation could be exchanged with 3H of tissue water, and that nonexchangeable 3H was fixed by photosynthesis. The kinetic behavior of the 2 forms was very different. PMID:6511427

  14. Susuk - black magic exposed "white" by dental radiographs.

    PubMed

    F, Arishiya Thapasum; Mohammed, Faraz

    2014-07-01

    Susuk or charm needles are a facial cum body art widely practiced among women of Malaysia, Brunei, Singapore, Thailand and Indonesia. These are small, needle-shaped metallic talismans inserted subcutaneously in different parts of the body. The concealed art of susuk was "exposed" by routine radiographic examination in the oral and maxillofacial region. This paper reports two such cases of unusual incidental radiographic finding in dental radiographs which were taken on a routine basis as part of the diagnostic work up. This article will also primarily enlighten the importance of radiographs in detecting such charm needles as the wearer keeps the body art a "hidden secret" thereby avoiding misdiagnosis. PMID:25177646

  15. Characteristics and outcomes of drug-exposed and non drug-exposed children in kinship and non-relative foster care

    Microsoft Academic Search

    Devon Brooks; Richard P. Barth

    1998-01-01

    This study describes the characteristics and outcomes of drug-exposed and non drug-exposed children in kinship and non-relative foster care. Outcomes included educational performance, emotional development, and problem behavior. Children were an average of 7.9 years old at the time of the study and were either 1.(a) non drug-exposed children placed with kin (n = 139),2.(b) drugexposed children placed with kin

  16. 76 FR 67761 - Hearing of the Attorney General's National Task Force on Children Exposed to Violence

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ...National Task Force on Children Exposed to Violence AGENCY: Office of Juvenile Justice and...National Task Force on Children Exposed to Violence (hereafter refered to as the Task Force...children's exposure to [[Page 67762

  17. PMMA Process Instructions Polymethyl methacrylate (PMMA) is widely used as a positive resist (when exposed to

    E-print Network

    Kim, Philip

    in the small or large yellow room fume hoods. Cleaning 1) Your tweezers should be cleaned before handling your exposed to radiation, the exposed region's chemical structure changes facilitating solubility

  18. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...84.86 Component parts exposed to oxygen pressures; minimum requirements. Each applicant shall...construction of component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for their intended...

  19. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...84.86 Component parts exposed to oxygen pressures; minimum requirements. Each applicant shall...construction of component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for their intended...

  20. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...84.86 Component parts exposed to oxygen pressures; minimum requirements. Each applicant shall...construction of component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for their intended...

  1. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...84.86 Component parts exposed to oxygen pressures; minimum requirements. Each applicant shall...construction of component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for their intended...

  2. 42 CFR 84.86 - Component parts exposed to oxygen pressures; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...84.86 Component parts exposed to oxygen pressures; minimum requirements. Each applicant shall...construction of component parts exposed to oxygen pressures above atmospheric pressure are safe and compatible for their intended...

  3. An update of mortality among chemical workers exposed to benzene.

    PubMed

    Bond, G G; McLaren, E A; Baldwin, C L; Cook, R R

    1986-10-01

    Mortality was updated to the end of 1982 for 594 employees exposed to benzene who had been studied previously and for an additional 362 exposed workers not studied previously. Cause specific mortality comparisons were made using United States white male, age, and calendar year adjusted rates. Total mortality was observed to have been significantly below expectation, and this was particularly evident for deaths from accidental causes. Mortality from skin cancer was significantly raised, although there were no unusual or common characteristics among the affected individuals which would suggest a link with exposure to benzene. A non-significant excess of total deaths from leukaemia was noted based on four observed cases; however, all four were myelogenous leukaemias and this represented a significant excess in that subcategory. These and other deaths of possible interest are reviewed in detail. Analyses by work area, duration of exposure, and cumulative dose index did not show patterns suggestive of a causal association between exposure to benzene and any particular cause of death. PMID:3465366

  4. Error-Related Negativities During Spelling Judgments Expose Orthographic Knowledge

    PubMed Central

    Harris, Lindsay N.; Perfetti, Charles A.; Rickles, Benjamin

    2014-01-01

    In two experiments, we demonstrate that error-related negativities (ERNs) recorded during spelling decisions can expose individual differences in lexical knowledge. The first experiment found that the ERN was elicited during spelling decisions and that its magnitude was correlated with independent measures of subjects’ spelling knowledge. In the second experiment, we manipulated the phonology of misspelled stimuli and observed that ERN magnitudes were larger when misspelled words altered the phonology of their correctly spelled counterparts than when they preserved it. Thus, when an error is made in a decision about spelling, the brain processes indexed by the ERN reflect both phonological and orthographic input to the decision process. In both experiments, ERN effect sizes were correlated with assessments of lexical knowledge and reading, including offline spelling ability and spelling-mediated vocabulary knowledge. These results affirm the interdependent nature of orthographic, semantic, and phonological knowledge components while showing that spelling knowledge uniquely influences the ERN during spelling decisions. Finally, the study demonstrates the value of ERNs in exposing individual differences in lexical knowledge. PMID:24389506

  5. Increased gluconeogenesis in rats exposed to hyper-G stress

    NASA Technical Reports Server (NTRS)

    Daligcon, B. C.; Oyama, J.; Hannak, K.

    1985-01-01

    The effect of gluconeogenesis on the levels of plasma glucose and liver glycogen was studied in rats exposed to hyper-G stress. Incorporation of lactate, alanine, or glycerol, labeled with C-14, into plasma glucose and liver glycogen was measured in rats centrifuged at 3.1 G for 0.25, 0.50, and 1.0-hr periods, and was compared to noncentrifuged controls injected with appropriate glycogen precursors. It was found that exposure to G-stress leads to increased incorporation from all three substrates into both plasma glucose and liver glycogen. These early incorporation increases were blocked upon pre-G administration of 5-methoxyindole-2-carboxylic acid, a gluconeogenesis inhibitor, or propanolol, a beta-adrenergic blocker, as well as by adrenodemedullation. Results indicate that the rapid rise in plasma glucose, as well as in liver glycogen in rats exposed to hyper-G stress is due to an increased rate of gluconeogenesis, and that epinephrine, released in response to hyper-G-induced activation of the sympathetic-adrenal system, plays a dominant role during the early stages of hyper-G stress.

  6. Gender-related behavior in women exposed prenatally to diethylstilbestrol.

    PubMed Central

    Newbold, R R

    1993-01-01

    Accumulating evidence in experimental animals over the past three decades suggests that mammalian brain development and differentiation of the central nervous system are influenced by perinatal exposure to sex hormones. Hence, changes in human behavioral patterns may be associated with prenatal exposure to estrogenic substances such as diethylstilbestrol (DES). This paper reviews relevant studies from a series of laboratories and finds that no clear-cut differences can be demonstrated to date between unexposed and DES-exposed women in gender-related behavior, although the physical and psychological impact of the problems associated with exposure to DES are well documented. If both prenatal and postnatal influences such as social, economic, and environmental factors are taken into consideration, individual variation is more apparent than differences in gender-related behavior between unexposed and DES-exposed women. In summary, gender-related behavior is determined by a complex array of interacting factors, and prenatal influences are only one of many developmental events. More studies are needed using larger populations with carefully controlled selection criteria to suggest a direct role of prenatal DES exposure on subsequent gender-related behavior. Images p208-a PMID:8404755

  7. NMR relaxometry measurements of Fricke gel dosimeters exposed to neutrons

    NASA Astrophysics Data System (ADS)

    Marrale, Maurizio; Brai, Maria; Longo, Anna; Gallo, Salvatore; Tomarchio, Elio; Tranchina, Luigi; Gagliardo, Cesare; D'Errico, Francesco

    2014-11-01

    Fricke infused gel matrices offer several features making them suitable for dosimetric applications; among these there are tissue equivalence, low cost and ease of preparation. Their nuclear magnetic resonance (NMR) relaxation properties can be used as a radiation detector for the dosimetry of beams used in cancer therapy. In recent years neutron capture therapy has been resumed for the treatment of various types of cancer and it requires three-dimensional mapping of the neutron fields. In this work, we investigated this particular application through NMR relaxometry and MR imaging of Fricke gels exposed to neutrons. We analyzed both the R1 and R2 relaxation rates, which relate to the longitudinal T1 and transversal T2 relaxation times. In particular, we found that the relaxation rate R2 does not depend on the neutron fluence, whereas the relaxation rate R1 increases linearly with the fluence. The magnetic resonance imaging acquisitions showed that T1-weighted images allow the characterization of samples exposed to different neutron fluences.

  8. Proportional mortality patterns among chemical plant workers exposed to formaldehyde.

    PubMed Central

    Marsh, G M

    1982-01-01

    To examine the possible health risks associated with occupational exposure to formaldehyde a proportional mortality analysis was conducted on deaths occurring between 1950 and 1976 among 136 men who had been employed a month or more in one of five formaldehyde-related areas of a large chemical producing plant located in Springfield, Massachusetts, USA. Overall, no statistically significant excesses or deficits in proportional mortality were observed among the formaldehyde-exposed group based on comparisons with both United States men and men from the local county area. In addition, no important differences in mortality were observed among this group when comparisons were made with 456 male decedents from the same plant who had not had a month or more of formaldehyde exposure. Within the calendar period examined, no deaths from sinonasal cancer were observed among the chemical workers studied nor was mention made on any death certificate of sinonasal cancer as a contributory cause of death. No important excesses, trends, or patterns in cancer mortality were observed among white male formadelhyde-exposed workers when consideration was given to age and time period of death, type and duration of formaldehyde exposure, and the lapse period from the onset of the first formaldehyde-related job assignment. Although certain limitations of this study do not allow definite conclusions to be drawn, the results indicate no trends or patterns in proportional mortality that could be directly linked to exposures to formaldehyde. PMID:7138792

  9. Asbestos-exposed populations: prevention, care, and compensation

    SciTech Connect

    Richter, E.D.; Tulchinsky, T.; Goldsmith, J.R.; Yaffe, Y.

    1984-05-01

    In Israel, the prevention and care of asbestos-associated diseases with latency periods of one to four decades (asbestosis, mesothelioma, increased frequency of cancer of the lung and other sites) are not satisfactory, and new national policies are required. Such policies have three major goals: (a) elimination or reduction of exposure to asbestos dust; (b) measures to promote cessation or drastic reduction of cigarette smoking among those currently or formerly exposed; and (c) equitable compensation for the consequences of past exposures. The practical elements of a program to achieve these three goals include (a) exposure standards and control technology; (b) identification of sources, routes, and levels of exposure and groups at risk; (c) compensation and job security; (d) medical monitoring and follow-up; (e) smoking cessation; (f) selective substitution of other substances for asbestos; and (g) establishment of a panel for policy supervision and the overseeing of compensation programs. Delay in implementation risks higher death rates for asbestosis and cancer among previously exposed workers, greater exposure among current workers, loss of experienced workers from the work force, and unnecessary hardship for families not adequately compensated.

  10. Juveniles exposed to embryonic corticosterone have enhanced flight performance

    PubMed Central

    Chin, Eunice H.; Love, Oliver P.; Verspoor, Jan J.; Williams, Tony D.; Rowley, Kyle; Burness, Gary

    2008-01-01

    Exposure to maternally derived glucocorticoids during embryonic development impacts offspring phenotype. Although many of these effects appear to be transiently ‘negative’, embryonic exposure to maternally derived stress hormones is hypothesized to induce preparative responses that increase survival prospects for offspring in low-quality environments; however, little is known about how maternal stress influences longer-term survival-related performance traits in free-living individuals. Using an experimental elevation of yolk corticosterone (embryonic signal of low maternal quality), we examined potential impacts of embryonic exposure to maternally derived stress on flight performance, wing loading, muscle morphology and muscle physiology in juvenile European starlings (Sturnus vulgaris). Here we report that fledglings exposed to experimentally increased corticosterone in ovo performed better during flight performance trials than control fledglings. Consistent with differences in performance, individuals exposed to elevated embryonic corticosterone fledged with lower wing loading and had heavier and more functionally mature flight muscles compared with control fledglings. Our results indicate that the positive effects on a survival-related trait in response to embryonic exposure to maternally derived stress hormones may balance some of the associated negative developmental costs that have recently been reported. Moreover, if embryonic experience is a good predictor of the quality or risk of future environments, a preparative phenotype associated with exposure to apparently negative stimuli during development may be adaptive. PMID:18842541

  11. Experiences of being exposed to intimate partner violence during pregnancy

    PubMed Central

    Lidén, Eva; Lundgren, Ingela

    2012-01-01

    In this study a phenomenological approach was used in order to enter deeply into the experience of living with violence during pregnancy. The aim of the study was to gain a deeper understanding of women's experiences of being exposed to intimate partner violence (IPV) during pregnancy. The data were collected through in-depth interviews with five Norwegian women; two during pregnancy and three after the birth. The women were between the age of 20 and 38 years. All women had received support from a professional research and treatment centre. The essential structure shows that IPV during pregnancy is characterized by difficult existential choices related to ambivalence. Existential choices mean questioning one's existence, the meaning of life as well as one's responsibility for oneself and others. Five constituents further explain the essential structure: Living in unpredictability, the violence is living in the body, losing oneself, feeling lonely and being pregnant leads to change. Future life with the child is experienced as a possibility for existential change. It is important for health professionals to recognize and support pregnant women who are exposed to violence as well as treating their bodies with care and respect. PMID:22468147

  12. Radiographic abnormalities among construction workers exposed to quartz containing dust

    PubMed Central

    Tjoe, N; Burdorf, A; Parker, J; Attfield, M; van Duivenbooden, C; Heederik, D

    2003-01-01

    Background: Construction workers are exposed to quartz containing respirable dust, at levels that may cause fibrosis in the lungs. Studies so far have not established a dose-response relation for radiographic abnormalities for this occupational group. Aims: To measure the extent of radiographic abnormalities among construction workers primarily exposed to quartz containing respirable dust. Methods: A cross sectional study on radiographic abnormalities indicative of pneumoconiosis was conducted among 1339 construction workers mainly involved in grinding, (jack)-hammering, drilling, cutting, sawing, and polishing. Radiological abnormalities were determined by median results of the 1980 International Labour Organisation system of three certified "B" readers. Questionnaires were used for assessment of occupational history, presence of respiratory diseases, and symptoms and smoking habits. Results: An abnormality of ILO profusion category 1/0 and greater was observed on 10.2% of the chest radiographs, and profusion category of 1/1 or greater on 2.9% of the radiographs. The average duration of exposure of this group was 19 years and the average age was 42. The predominant type of small opacities (irregularly shaped) is presumably indicative of mixed dust pneumoconiosis. The prevalence of early signs of nodular silicosis (small rounded opacities of category 1/0 or greater) was low (0.8%). Conclusions: The study suggests an elevated risk of radiographic abnormalities among these workers with expected high exposure. An association between radiographic abnormalities and cumulative exposure to quartz containing dust from construction sites was observed, after correction for potentially confounding variables. PMID:12771392

  13. White Matter Compromise in Veterans Exposed to Primary Blast Forces

    PubMed Central

    Taber, Katherine H.; Hurley, Robin A.; Haswell, Courtney C.; Rowland, Jared A.; Hurt, Susan D.; Lamar, Cory D.; Morey, Rajendra A.

    2015-01-01

    Objective Use Diffusion Tensor Imaging (DTI) to investigate white matter alterations associated with blast exposure with or without acute symptoms of traumatic brain injury (TBI). Participants Forty-five veterans of the recent military conflicts included twenty-three exposed to primary blast without TBI symptoms, six having primary blast mild TBI, and sixteen unexposed to blast. Design Cross-sectional case control study. Main Measures Neuropsychological testing and DTI metrics that quantified the number of voxel clusters with altered fractional anisotropy (FA) radial diffusivity (RD), and axial diffusivity (AD), regardless of their spatial location. Results Significantly lower FA and higher RD was observed in veterans exposed to primary blast with and without mild TBI relative to blast unexposed veterans. Voxel clusters of lower FA were spatially dispersed and heterogeneous across affected individuals. Conclusion These results suggest that lack of clear TBI symptoms following primary blast exposure may not accurately reflect the extent of brain injury. If confirmed, our findings would argue for supplementing the established approach of making diagnoses based purely on clinical history and observable acute symptoms with novel neuroimaging-based diagnostic criteria that “look below the surface” for pathology. PMID:24590156

  14. The ORGANIC experiment on EXPOSE-R on the ISS: Flight sample preparation and ground control spectroscopy

    NASA Astrophysics Data System (ADS)

    Bryson, K. L.; Peeters, Z.; Salama, F.; Foing, B.; Ehrenfreund, P.; Ricco, A. J.; Jessberger, E.; Bischoff, A.; Breitfellner, M.; Schmidt, W.; Robert, F.

    2011-12-01

    In March of 2009, the ORGANIC experiment integrated into the European multi-user facility EXPOSE-R, containing experiments dedicated to Astrobiology, was mounted through Extra Vehicular Activity (EVA) externally on the International Space Station (ISS). The experiment exposed organic samples of astronomical interest for a duration of 97 weeks (˜22 months) to the space environment. The samples that were returned to Earth in spring 2011, received a total UV radiation dose during their exposure including direct solar irradiation of >2500 h, exceeding the limits of laboratory simulations. We report flight sample preparation and pre-flight ultraviolet-visible (UV-Vis) characterization of the ORGANIC samples, which include 11 polycyclic aromatic hydrocarbons (PAHs) and three fullerenes. The corresponding time-dependent ground control monitoring experiments for ORGANIC measured over ˜19 months are presented and the results anticipated upon return of the samples are discussed. We present the first UV-Vis spectrum of solid circobiphenyl (C 38H 16). Further, we present the first published UV-Vis spectra of diphenanthro[9,10-b',10'-d]thiophene (C 28H 16S), dinaphtho[8,1,2-abc,2',1',8'-klm]coronene (C 36H 16), tetrabenzo[de,no,st,c'd']heptacene (C 42H 22), and dibenzo[jk,a'b']octacene (C 40H 22) in solid phase and in solution. The results of the ORGANIC experiment are expected to enhance our knowledge of the evolution and degradation of large carbon-containing molecules in space environments.

  15. Methicillin Resistant Staphylococcus aureus Carriage, Antibiotic Resistance and Molecular Pathogenicity among Healthy Individuals Exposed and Not Exposed to Hospital Environment

    PubMed Central

    Krishnamurthy, Veena; Renushri, Bhadravati Virupaksha; Nagaraj, Elkal Rajappa

    2014-01-01

    Background: Healthcare workers as well as healthy community-dwelling individuals may be colonised by methicillin-resistant Staphylococcus aureus (MRSA). Healthcare workers who carry MRSA may transmit it to patients, causing various nosocomial infections. Literature shows that the differences between MRSA isolated from healthcare settings and from community settings, with regard to multi-drug resistance (traditionally exhibited by the former) and possession of pvl genes (traditionally exhibited by the latter), is diminishing due to a large community reservoir and increasing influx of community harboured strains into the hospital. However, there is no literature on the current scenario in India. Aims and Objectives: This study examines the influence of exposure to hospital environment on MRSA carriage, antimicrobial resistance patterns of MRSA, and the presence of genes encoding five extracellular pathogenicity determinants (pvl, sea, seb, tsst-1 and hly a). Materials and Methods: Nasal, throat and palmar swabs were collected from 119 nursing students of the age group 18-23 years (exposed group) and 100 age matched pharmacy students (non-exposed group). S. aureus was identified and antibiogram obtained as per Clinical and Laboratory Standards Institute (CLSI) guidelines. MRSA was detected by cefoxitin disc diffusion test and by growth on oxacillin screen agar as per CLSI guidelines. Conventional PCR was performed for mecA, pvl, sea, seb, tsst-1 and hly a. Results: The differences in carrier rates, antibiotic resistance patterns and expression of extracellular pathogenicity determinants between MRSA isolates from the two study groups were not significant, and pvl was found in all the MRSA isolates. Conclusion: The nursing students carried MRSA strains similar to those carried by the non-exposed group. Our results suggest that healthcare workers could act as a link and transmit MRSA acquired from the community to patients. PMID:25177563

  16. Serum endothelin concentrations in workers exposed to vibration.

    PubMed Central

    Palmer, K T; Mason, H

    1996-01-01

    OBJECTIVES: Endothelin 1 (ET1) is one of a newly discovered family of potent naturally occurring vasoconstrictors produced by the endothelium. A few publications indicated that the peptide may have a role in idiopathic Raynaud's phenomenon and Raynaud's phenomenon secondary to connective tissue disease. The aim of this study was to compare serum endothelin concentrations in people with vibration induced white finger (VWF) with those of controls exposed to vibration, and unexposed (pure) controls. SUBJECTS AND METHODS: Male volunteers from a stonemasonry, two quarries, and an insurance company were classified by questionnaire and clinical examination into men with VWF (cases, n = 31), exposed controls (n = 22), or pure controls (n = 36). All subjects were asked to provide two venous blood specimens: a baseline sample after a period of warm equilibration (30 minutes seated in a warm room and 20 minutes with both hands immersed in a water bath at 37 degrees C); and again after cold challenge (both hands immersed in a water bath at 6 degrees C for six minutes). Serum concentrations of the 21 amino acid peptide endothelin ET1-21 were measured by radioimmunoassay. RESULTS: Baseline concentrations of ET1-21 were found to be lower in cases (mean = 12.2 pmol/l) than in the two control groups (mean = 14.7 pmol/l in exposed controls; mean = 14.3 pmol/l in pure controls). Among cases there was a broad inverse relation between severity, as measured by the Griffin blanching score, and baseline ET1-21 (Spearman rank correlation coefficient -0.58, P < 0.001). Cold challenge provoked an overall rise in ET1-21 in all groups, but larger and significant mean absolute and percentage rises were found in cases (4.1 pmol/l and 54%) than in the control groups (2.6 pmol/l and 21% in exposed controls; 1.5 pmol/l and 20% in pure controls). Similar but more obvious differences occurred when controls were compared with those cases who gave a more severe history of disease (Griffin blanching score > or = 24) and those cases found to blanch after cold challenge. In these case subsets baseline ET1-21 was nearly 50% lower than for controls and a four and a half to fivefold greater percentage rise in ET1-21 occurred upon cold challenge. Differences were significant. Close matching for age and smoking did not alter the principal findings. No significant differences, whether in baseline or cold response, were found between unexposed and exposed controls. CONCLUSIONS: Baseline findings seem to contradict various published series and attempts are made to reconcile the differences. It is suggested that a lower baseline ET1-21 in cases may result from a disease compensation mechanism or damage effect. The large relative rise in serum ET1-21 when cases are cold challenged may contribute directly or indirectly to vasospasm, but a simple mechanism is unlikely and interpretation is limited by the absence of measurements of forearm blood flow. PMID:8777448

  17. Marital Relationship and Its Associated Factors in Veterans Exposed to High Dose Chemical Warfare Agents

    Microsoft Academic Search

    Shervin Assari; Mohammad Reza Soroush; Hamid Reza; Khoddami Vishteh; Batol Mousavi; Mostafa Ghanei; Sima Karbalaeiesmaeili

    2008-01-01

    Objective: The aim of this study was to determine the associates of marital relationship in mustard exposed veterans. Materials and Methods: Two hundred ninety two married Iranian mustard exposed veterans, who had been exposed to single high dose mustard gas in Iraq-Iran war, were assessed for marital adjustment with Revised Dyadic Adjustment Scale (RDAS). Census sampling was done. The patients'

  18. Health care facility-based decontamination of victims exposed to chemical, biological, and radiological materials

    E-print Network

    Koenig, Kristi L MD

    2008-01-01

    Health care facility-based decontamination of victims exposed to chemical, biological, and radiologicalHealth care facility-based decontamination of victims exposed to chemical, biological, and radiologicalHealth care facility-based decontamination of victims exposed to chemical, biological, and radiological

  19. Flicker Fusion Test and Occupational Toxicology: Performance Evaluation in Workers Exposed to Lead and Solvents

    Microsoft Academic Search

    Alberto Betta; Azelio De Santa; Cecilia Savonitto; Franco DAndrea

    1983-01-01

    1 In a group of 108 workers professionally exposed to low lead levels and in 35 shoe factory workers exposed to a mixture of solvents, neurotoxic effects were evaluated by means of Critical Flicker Frequency, used as single test of psychophysiological performance.2 A statistically significant lowering of CFF threshold was observed and, in the lead exposed group, this decrease is

  20. 77 FR 22000 - Hearing of the Attorney General's National Task Force on Children Exposed to Violence

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-12

    ...National Task Force on Children Exposed to Violence AGENCY: Office of Justice Programs...National Task Force on Children Exposed to Violence (the ``task force''). The task...advice in the areas of children exposed to violence for the purpose of addressing the...

  1. 77 FR 39264 - Meeting of the Attorney General's National Task Force on Children Exposed to Violence

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ...National Task Force on Children Exposed to Violence AGENCY: Office of Justice Programs...National Task Force on Children Exposed to Violence (the ``task force''). The task...advice in the areas of children exposed to violence for the purpose of addressing the...

  2. 77 FR 12881 - Hearing of the Attorney General's National Task Force on Children Exposed to Violence

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-02

    ...National Task Force on Children Exposed to Violence AGENCY: Office of Justice Programs...National Task Force on Children Exposed to Violence (the ``task force''). The task...advice in the areas of children exposed to violence for the purpose of addressing the...

  3. Cytokine mRNA profiles in pigs exposed prenatally and postnatally to Schistosoma japonicum

    Microsoft Academic Search

    Michala E. Techau; Maria V. Johansen; Bent Aasted; Peter Lind; Niel Ornbjerg; Isabelle P. Oswald

    2007-01-01

    The pig is a natural host for Schistosoma japonicum and a useful animal model of human infection. The aim of the present study was to assess the differences between the cytokine profiles in prenatally or postnatally S. japonicum exposed pigs. Seven prenatally exposed pigs, 7 postnatally exposed pigs and 4 uninfected control pigs were compared 27 weeks post exposure. Variables

  4. Immuno-fluorescence Assay of Leptospiral Surface-exposed Proteins

    PubMed Central

    Pinne, Marija; Haake, David

    2011-01-01

    Bacterial surface proteins are involved in direct contact with host cells and in uptake of nutrients from the environment 1. For this reason, cellular localization can provide insights into the functional role of bacterial proteins. Surface localization of bacterial proteins is a key step towards identification of virulence factors involved in mechanisms of pathogenicity. Methods for fractionating leptospiral membranes 2-5 may be selective for a certain class of outer-membrane proteins (OMPs), such as lipoproteins vs. transmembrane OMPs, and therefore lead to misclassification. This likely is due to structural differences and how they are associated to the outer membrane. Lipoproteins are associated with membranes via a hydrophobic interaction between the N-terminal lipid moiety (three fatty acids) and the lipid bilayer phospholipids 6, 7. In contrast, transmembrane OMPs are typically integrated into the lipid bilayer by amphipathic ?-sheets arranged in a barrel-like structure 8, 9. In addition, presence of a protein in the outer-membrane does not necessarily guarantee that the protein or its domains are exposed on the surface. Spirochetal outer membranes are known to be fragile and therefore necessitate methods involving gentle manipulation of cells and inclusion of sub-surface protein controls to assess the integrity of the outer membrane. Here, we present an immunofluorescence assay (IFA) method to directly assess surface exposure of proteins on intact leptospires. This method is based on recognition of leptospiral surface proteins by antigen-specific antibodies. Herein, antibodies specific for OmpL5410 are detetcted aftero binding to native, surface exposed epitopes. Comparison of antibody reactivity to intact versus permeabilized cells enables evaluation of cellular distribution and whether or not a protein is selectively present on leptospiral surface. The integrity of outer membrane should be assessed using antibody to one or more subsurface proteins, preferably located in the periplasm. The surface IFA method can be used to analyze surface exposure of any leptospiral protein to which specific antibodies are available. Both the usefulness and limitation of the method depends on whether the antibodies employed are able to bind to native epitopes. Since antibodies often are raised against recombinant proteins, epitopes of native, surface-exposed proteins may not be recognized. Nevertheless, the surface IFA method is a valuable tool for studying components of intact bacterial surfaces. This method can be applied not only for leptospires but also other spirochetes and gram-negative bacteria. For stronger conclusions regarding surface-exposure of OMPs, a comprehensive approach involving several cell localization methods is recommended 10. PMID:21750491

  5. Cytogenetic Monitoring of Farmers exposed to pesticides in Colombia.

    PubMed Central

    Hoyos, L S; Carvajal, S; Solano, L; Rodriguez, J; Orozco, L; López, Y; Au, W W

    1996-01-01

    We have monitored 30 pesticide-exposed workers and 30 matched controls for expression of chromosome aberrations (CA) and sister chromatid exchanges (SCE) in their lymphocytes. Peripheral blood cultures were set up within 3 hr after the collection of samples, and four cultures were set up from each donor. For CA analysis, 100 complete metaphase cells from each donor were evaluated. For the SCE assay, 50 complete metaphase cells from each donor were analyzed. The CA and SCE data were analyzed for differences between the two groups using the chi 2 and the Student's t-test, respectively. From the CA analysis it was obvious that the overwhelming majority of aberrations were chromatid breaks and isochromatid breaks; therefore, only these data are presented and used for statistical analysis. Isochromatid breaks were counted as two breaks each and chromatid breaks as one in calculating the total chromatid break frequencies. Statistical evaluation of the data indicates that there is no significant difference (p > 0.05; chi 2 test) between the exposed and the nonexposed groups based on chromatid breaks per 100 cells (1.2 +/- 0.3 and 1.5 +/- 0.2, respectively) and total chromatid breaks per 100 cells (1.7 +/- 0.3 and 2.1 +/- 0.2, respectively). No significantly difference between the two groups (p > 0.05, Student's t-test) was observed with SCE frequencies (5.0 +/- 1.1 and 4.8 +/- 0.9, respectively). Linear regression analysis indicates that the data were not influenced by age, cigarette smoking, or alcohol consumption. It is assuring that the exposure conditions among these Indian farmers have not caused detectable increases of chromosome damage using standard assays; this suggests the lack of serious long-term health problems. However, periodic monitoring of such exposed populations should be conducted using the same or other more sensitive assays. In addition, other populations with exposure to different types of pesticides in Colombia should also be investigated. PMID:8781378

  6. Acute physiological responses of squirrel monkeys exposed to hyperdynamic environments

    NASA Technical Reports Server (NTRS)

    Fuller, C. A.

    1984-01-01

    Physiological and behavioral responses to a hyperdynamic environment were examined in four adult male squirrel monkeys. After baseline monitoring at 1 G, monkeys were exposed to one of three conditions: (1) +2 Gz for 60 minutes, (2) +2.9 Gz max for 8 minutes (simulating Space Shuttle launch), or (3) +1.7 Gz max for 19 minutes (simulating Space Shuttle reentry). During all experimental conditions, heart rate rose, and colonic temperature began to decline within the first ten minutes of centrifugation and decreased by as much as 2 C in some instances. Behaviorally, during centrifugation, the monkeys seemed to exhibit drowsiness and fall asleep, an observation not made during the control period. It is concluded that primates are susceptible to acute hyperdynamic field exposure.

  7. DNA damage in Wistar rats exposed to dithiocarbamate pesticide mancozeb.

    PubMed

    Goldoni, A; Klauck, C R; Da Silva, S T; Da Silva, M D; Ardenghi, P G; Da Silva, L B

    2014-01-01

    Pesticides are used in large amounts in agriculture and the evaluation of their toxic effects is of major concern to public and environmental health. The aim of the present study was to investigate the genotoxic potential of a commercial formulation of the fungicide mancozeb by the micronucleus test in bone marrow and the comet assay in total blood of Wistar rats. Adult male Wistar rats were treated with a solution of mancozeb at a concentration of 40 mg/kg/day, administered intraperitoneally for 18 consecutive days, and compared to a control group. The results indicate that mancozeb induced significantly higher DNA damage as detected by the comet assay and increased the frequency of micronuclei. The results show that mancozeb is genotoxic and may adversely affect the DNA integrity of exposed organisms. PMID:25152054

  8. Solvent-exposed tryptophans probe the dynamics at protein surfaces.

    PubMed Central

    Lakshmikanth, G S; Krishnamoorthy, G

    1999-01-01

    The dynamics of single tryptophan (W) side chain of protease subtilisin Carlsberg (SC) and myelin basic protein (MBP) were used for probing the surface of these proteins. The W side chains are exposed to the solvent, as shown by the extent of quenching of their fluorescence by KI. Time-resolved fluorescence anisotropy measurements showed that the rotational motion of W is completely unhindered in the case of SC and partially hindered in the case of MBP. The rotational correlation time (phi) associated with the fast local motion of W did not scale linearly with the bulk solvent viscosity (eta) in glycerol-water mixtures. In contrast, phi values of either W side chains in the denatured proteins or the free W scaled almost linearly with eta, as expected by the Stokes-Einstein relationship. These results were interpreted as indicating specific partitioning of water at the surface of the proteins in glycerol-water mixtures. PMID:10423454

  9. Cancer incidence in an occupational cohort exposed to bitumen fumes.

    PubMed

    Hansen, E S

    1989-04-01

    This study was conducted to investigate whether bitumen fumes should be considered carcinogenic to human beings. A historical cohort of heavily exposed mastic asphalt workers was followed from 1959 through 1984 (inclusive) with regard to cancer incidence. A total of 679 Danish men were included in the study cohort. Among these, 75 new cases of cancer were observed within the period studied. The cancer incidence observed among the group significantly exceeded that of the total Danish male population, the standardized morbidity ratio (SMR) being 195 (95% confidence interval (95% CI) 153-244). Significant increases were seen for cancer of the mouth (SMR 1111, 95% CI 135-4014), the esophagus (SMR 698, 95% CI 144-2039), the rectum (SMR 318, 95% CI 128-656), and the lung (SMR 344, 95% CI 227-501). It is suggested that exposure to cracking products in the fumes of heated bitumen has contributed to the elevated cancer incidence observed. PMID:2772572

  10. Mapping the lipid-exposed surfaces of membrane proteins.

    PubMed

    Arkin, I T; MacKenzie, K R; Fisher, L; Aimoto, S; Engelman, D M; Smith, S O

    1996-03-01

    Phospholamban forms a stable complex of five long transmembrane helices. We show that the relative rotational orientation of the helices in the pentameric complex can be distinguished by S-H to S-D exchange of cysteine sulphydryl groups located in the transmembrane segment of the protein and exposed to the lipid environment. Of the three cysteine residues in phospholamban, two residues (Cys 36 and Cys 46) are oriented towards the helix interface and protected from exchange, while the third cysteine (Cys 41) is oriented towards the lipid interface and undergoes exchange with water diffused into the bilayer. Distinguishing the external and internal faces of a membrane protein by sulphydryl exchange provides a general approach for determining the three-dimensional fold of membrane proteins and enhances model building efforts to generate high-resolution structures. PMID:8605625

  11. Health effects among refrigeration repair workers exposed to fluorocarbons.

    PubMed Central

    Campbell, D D; Lockey, J E; Petajan, J; Gunter, B J; Rom, W N

    1986-01-01

    Refrigeration repair workers may be intermittently exposed to fluorocarbons and their thermal decomposition products. A case of peripheral neuropathy (distal axonopathy) in a commercial refrigeration repairman prompted an epidemiological investigation of the health of refrigeration repair workers. No additional cases of peripheral neuropathy were identified among the 27 refrigeration repair workers studied. A reference group of 14 non-refrigeration repair workers was also studied. No differences were noted between groups for the ulnar (motor and sensory), median (motor and sensory), peroneal, sural, or tibial nerve conduction velocities. Refrigeration repair workers reported palpitations and lightheadedness significantly more often than workers in the reference group. No clinical neurological or electroneurophysiological abnormalities were detected in eight refrigeration repair workers followed up for three years during continuous employment. PMID:3004555

  12. Cancer mortality among workers exposed to chemicals during uranium processing.

    PubMed

    Ritz, B

    1999-07-01

    Data provided by the Comprehensive Epidemiology Data Resource allowed us to study patterns of cancer mortality as experienced by 3814 uranium-processing workers employed at the Fernald Feed Materials Production Center in Fernald, Ohio. Using risk-set analyses for cohorts, we estimated the effects of exposure to trichloroethylene, cutting fluids, and kerosene on cancer mortality. Our results suggest that workers who were exposed to trichloroethylene experienced an increase in mortality from cancers of the liver. Cutting-fluid exposure was found to be strongly associated with laryngeal cancers and, furthermore, with brain, hemato- and lymphopoietic system, bladder, and kidney cancer mortality. Kerosene exposure increased the rate of death from several digestive-tract cancers (esophageal, stomach, pancreatic, colon, and rectal cancers) and from prostate cancer. Effect estimates for these cancers increased with duration and level of exposure and were stronger when exposure was lagged. PMID:10412097

  13. Western Candor Chasma - Layers exposed near the middle

    NASA Technical Reports Server (NTRS)

    1998-01-01

    One of the most striking discoveries of the Mars Global Surveyor mission has been the identification of thousands of meters/feet of layers within the wall rock of the enormous martian canyon system, Valles Marineris.

    Valles Marineris was first observed in 1972 by the Mariner 9 spacecraft, from which the troughs get their name: Valles--valleys, Marineris--Mariner.

    Some hints of layering in both the canyon walls and within some deposits on the canyon floors were seen in Mariner 9 and Viking orbiter images from the 1970s. The Mars Orbiter Camera on board Mars Global Surveyor has been examining these layers at much higher resolution than was available previously.

    MOC images led to the realization that there are layers in the walls that go down to great depths. An example of the wall rock layers can be seen in MOC image 8403, shown above (C).

    MOC images also reveal amazing layered outcrops on the floors of some of the Valles Marineris canyons. Particularly noteworthy is MOC image 23304 (D, above), which shows extensive, horizontally-bedded layers exposed in buttes and mesas on the floor of western Candor Chasma. These layered rocks might be the same material as is exposed in the chasm walls (as in 8403--C, above), or they might be rocks that formed by deposition (from water, wind, and/or volcanism) long after Candor Chasma opened up.

    In addition to layered materials in the walls and on the floors of the Valles Marineris system, MOC images are helping to refine our classification of geologic features that occur within the canyons. For example, MOC image 25205 (E, above), shows the southern tip of a massive, tongue-shaped massif (a mountainous ridge) that was previously identified as a layered deposit. However, this MOC image does not show layering. The material has been sculpted by wind and mass-wasting--downslope movement of debris--but no obvious layers were exposed by these processes.

    Valles Marineris a fascinating region on Mars that holds much potential to reveal information about the early history and evolution of the red planet. The MOC Science Team is continuing to examine the wealth of new data and planning for new Valles Marineris targets once the Mapping Phase of the Mars Global Surveyor mission commences in March 1999.

    Layers exposed near the middle of western Candor Chasma. MOC image 23304 subframe shown at 10.7 meters (35 feet) per pixel. Two layered buttes (upper right and lower right) and a layered or stepped mesa (center right) are shown. The image covers an area approximately 5.5 by 5.5 kilometers (3.4 x 3.4 miles). North is approximately up, illumination is from the lower right. Image 23304 was obtained during Mars Global Surveyor's 233rd orbit at 9:23 a.m. (PDT) on April 11, 1998.

    Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  14. Ion irradiated graphite exposed to fusion-relevant deuterium plasma

    NASA Astrophysics Data System (ADS)

    Deslandes, Alec; Guenette, Mathew C.; Corr, Cormac S.; Karatchevtseva, Inna; Thomsen, Lars; Ionescu, Mihail; Lumpkin, Gregory R.; Riley, Daniel P.

    2014-12-01

    Graphite samples were irradiated with 5 MeV carbon ions to simulate the damage caused by collision cascades from neutron irradiation in a fusion environment. The ion irradiated graphite samples were then exposed to a deuterium plasma in the linear plasma device, MAGPIE, for a total ion fluence of ?1 × 1024 ions m-2. Raman and near edge X-ray absorption fine structure (NEXAFS) spectroscopy were used to characterize modifications to the graphitic structure. Ion irradiation was observed to decrease the graphitic content and induce disorder in the graphite. Subsequent plasma exposure decreased the graphitic content further. Structural and surface chemistry changes were observed to be greatest for the sample irradiated with the greatest fluence of MeV ions. D retention was measured using elastic recoil detection analysis and showed that ion irradiation increased the amount of retained deuterium in graphite by a factor of four.

  15. Corrosion behavior of materials exposed to hypersaline geothermal brine

    SciTech Connect

    McCright, R.D.

    1980-11-20

    The corrosion rate and corrosion attack characteristics were determined for thirteen commercially available materials exposed in a geothermal production well for three months. The materials included carbon steels, Cr-Mo alloy steels, martensitic and ferritic stainless steels, high-nickel alloys, and titanium. The environment at the 1800 ft (600 m) depth of exposure was a single phase high salinity brine. The prevailing temperature was 260{sup 0}C and the prevailing pressure was 630 psi (4.0 MPa) during the exposure period. Results indicated that the carbon steels suffered intense generalized and localized corrosion. Addition of Cr and Mo to steels imparted significant improvement in the corrosion performance in this aggressive environment. Of the stainless steels tested, the most resistant were those containing a few percent molybdenum.

  16. Wear of connector contacts exposed to relative motion

    NASA Astrophysics Data System (ADS)

    Wilk, R. A.

    Connectors play a significant role in the performance, cost, and reliability of electronic equipment. In connection with the development of the system interconnection design, a factor which is often overlooked is related to the importance of connector selection and mounting to minimize relative motion between contacts during vibration encountered in handling, transportation, and service. This motion can lead to the loss of protective coatings (gold and nickel) due to frictional wear. If this happens, fretting corrosion of the base metals may occur. The produced damage can adversely affect performance due to increased joint resistance, eventually causing intermittent contacts. The present investigation is concerned with the study of different style contacts (tuning fork, box, and circular) to determine their endurance and wear characteristics when exposed to relative motion created by vibration. All contacts investigated were fabricated from brass, beryllium copper, or phosphor bronze, and had .00127 mm minimum gold plating over .00127 mm minimum nickel plating.

  17. Microstructure, morphology and lifetime of armored bubbles exposed to surfactants

    E-print Network

    Anand Bala Subramaniam; Cecile Mejean; Manouk Abkarian; Howard A. Stone

    2006-02-16

    We report the behavior of particle-stabilized bubbles (armored bubbles) when exposed to various classes and concentrations of surfactants. The bubbles are non-spherical due to the jamming of the particles on the interface and are stable to dissolution prior to the addition of surfactant. We find that the dissolving bubbles exhibit distinct morphological, microstructural, and lifetime changes, which correlate with the concentration of surfactant employed. For low concentrations of surfactant an armored bubble remains non-spherical while dissolving, while for concentrations close to and above the surfactant CMC a bubble reverts to a spherical shape before dissolving. We propose a microstructural interpretation, supported by our experimental observations of particle dynamics on the bubble interface, that recognizes the role of interfacial jamming and stresses in particle stabilization and surfactant-mediated destabilization of armored bubbles.

  18. Chromosome Aberration in Human Blood Lymphocytes Exposed to Energetic Protons

    NASA Technical Reports Server (NTRS)

    Hada, M.; George, Kerry A.; Cucinotta, F. A.

    2008-01-01

    During space flight, astronauts are exposed to a space radiation consisting of high-energy protons, high charge and energy (HZE) nuclei, as well as secondary particles that are generated when the primary particles penetrate the spacecraft shielding. Secondary particles have a higher LET value than primary protons and therefore expected to have a higher relative biological effectiveness (RBE). To investigate this theory, we exposed human peripheral blood lymphocytes to protons with energies of 250 MeV, 800MeV, 2 GeV, or 2.5 GeV. LET values for these protons ranged from 0.4 to 0.2 keV/micrometer. and doses ranged from 0.2 to 3 Gy. Over this energy the probability of nuclear reaction leading to secondary radiation, and the multiplicity of reaction produces such as neutrons and mesons increases substantially. The effect of aluminum and polyethylene shielding was also assessed using the 2 GeV and 2.5GeV proton beams. After exposure lymphocytes were stimulated to divide and chromosomes were collected from cells in the first G2 and metaphase cell cycle after exposure using a chemical induced premature chromosome condensation (PCC) technique. Dose response data for chromosome damage was analyzed using the fluorescence in situ hybridization (FISH) chromosome painting technique. Selected samples were also analyzed with multicolor FISH (mFISH) and multicolor banding FISH (mBAND) techniques. Data indicates that the dose response for simple-type exchanges is similar for proton and gamma exposure, whereas protons induce higher yields of complex exchanges that are LET dependent. RBE values will be presented for each proton energy, and the effects of shielding and possible cytogenetic signatures of proton exposure will be discussed.

  19. Altered glutathione homeostasis in animals prenatally exposed to lipopolysaccharide

    PubMed Central

    Zhu, Yuangui; Carvey, Paul M.; Ling, Zaodung

    2007-01-01

    We previously reported that injection of bacterial lipopolysaccharide (LPS) into gravid female rats at embryonic day 10.5 resulted in a birth of offspring with fewer than normal dopamine (DA) neurons along with innate immunity dysfunction and many characteristics seen in Parkinson’s disease (PD) patients. The LPS-exposed animals were also more susceptible to secondary toxin exposure as indicated by an accelerated DA neuron loss. Glutathione (GSH) is an important antioxidant in the brain. A disturbance in glutathione homeostasis has been proposed for the pathogenesis of PD. In this study, animals prenatally exposed to LPS were studied along with an acute intranigral LPS injection model for the status of glutathione homeostasis, lipid peroxidation, and related enzyme activities. Both prenatal LPS exposure and acute LPS injection produced a significant GSH reduction and increase in oxidized GSH (GSSG) and lipid peroxide (LPO) production. Activity of ?-glutamylcysteine synthetase (GCS), the rate-limiting enzyme in de novo GSH synthesis, was up-regulated in acute supranigral LPS model but was reduced in the prenatal LPS model. The GCS light subunit protein expression was also down-regulated in prenatal LPS model. GSH redox recycling enzyme activities (glutathione peroxidase, GPx and glutathione reducdase, GR) and glutathione S-transferase (GST), ?-glutamyl transpeptidase (?-GT) activities were all increased in prenatal LPS model. Prenatal LPS exposure and aging synergized in GSH level and GSH related enzyme activities except for those (GR, GST, and ?-GT) with significant regional variations. Additionally, prenatal LPS exposure produced a reduction of DA neuron count in the substantia nigra (SN). These results suggest that prenatal LPS exposure may cause glutathione homeostasis disturbance in offspring brain and render DA neurons susceptible to the secondary neurotoxin insult. PMID:17291629

  20. Biological monitoring of a worker acutely exposed to MBOCA

    SciTech Connect

    Osorio, A.M.; Clapp, D.; Ward, E.; Wilson, H.K.; Cocker, J. (NIOSH, DSHEFS, Cincinnati, OH (USA))

    1990-01-01

    A 30 year-old male polyurethane worker was exposed to an accidental spill of 4,4'-methylene-bis-2-chloroaniline (MBOCA) at a plant producing MBOCA-cured plastic products. Exposure to MBOCA is significant in that this compound is a known animal carcinogen and a suspected human carcinogen. The employee was sprayed over his upper body and extremities with molten MBOCA while cleaning out a clogged hose from a MBOCA and polymer mixing machine. The subsequent environmental and medical evaluation of this episode included serial urinary MBOCA samples from the worker over a 2 week period to allow the calculation of a biological half-life for this compound. This worker experienced a very high dose of MBOCA as judged by his urinary MBOCA levels (peak value of 1,700 ppb 4 hours after exposure). There were no acute symptoms or other laboratory abnormalities noted. The kinetic evaluation resulted in a biological half-life for MBOCA in urine of approximately 23 hours. Assuming a one-compartment model, approximately 94% of an initial MBOCA dose will be eliminated within four days. This is the first report of kinetic analysis on urinary MBOCA excretion in humans. This information suggests that biological monitoring of the urine MBOCA concentrations in exposed workers may miss peak levels following an acute exposure unless the analyses of the urinary MBOCA are performed in a timely fashion. Recommendations to the company included: (1) installation of a warning system or lock-out device on the mixing machine to prevent the opening of the MBOCA hose prior to the release of pressure; and (2) annual medical surveillance of this individual for bladder cancer with urinalysis and urine cytology.

  1. Kidney effects in long term exposed lead smelter workers.

    PubMed Central

    Gerhardsson, L; Chettle, D R; Englyst, V; Nordberg, G F; Nyhlin, H; Scott, M C; Todd, A C; Vesterberg, O

    1992-01-01

    Occupational exposure to lead may cause kidney damage. This study was carried out on a cohort of 70 active and 30 retired long term exposed lead smelter workers. Their kidney function was compared with 31 active and 10 retired truck assembly workers who had no occupational exposure to lead. The lead workers had been regularly followed up with measurements of lead concentration in blood since 1950. Previous exposure to lead was calculated as a time integrated blood lead index for each worker. Blood and urine samples were obtained from all subjects. The concentration of lead in blood (B-Pb) and urine (U-Pb) was analysed. The urinary concentrations of several sensitive indicators of early tubular (U-beta 2-microglobulin (U-beta 2-m); U-N-acetyl-beta-glucosaminidase (U-NAG)) and glomerular kidney damage (U-albumin) were determined. The B-Pb and U-Pb values were significantly higher among active and retired lead workers compared with their corresponding control groups. The highest concentrations were found among the active lead workers. The concentrations of the parameters of kidney function investigated were of the same magnitude for exposed workers and controls. No clinical signs of renal impairment were found among the workers. No correlations of clinical importance existed between concentrations of U-albumin, U-beta 2-m, and U-NAG activity on the one hand and the concentrations of B-Pb, cumulative blood lead index, U-Pb, and lead concentrations in the calcaneus and tibia on the other, among lead workers and controls. Despite many years of moderate to heavy exposure to lead, particularly for the retired lead workers, no signs of adverse effects on the kidney such as early tubular or glomerular malfunction were found. Reversible changes in kidney function during the 1950s and 1960s could not be excluded, however, due to a greater exposure to lead during that time. PMID:1554615

  2. Chromosome aberrations in human blood lymphocytes exposed to energetic protons

    NASA Astrophysics Data System (ADS)

    Hada, Megumi; George, Ms Kerry; Cucinotta, Francis A.

    During space flight, astronauts are exposed to space radiation consisting of high-energy protons, high charge and energy (HZE) nuclei, as well as secondary particles that are generated when the primary particles penetrate the spacecraft shielding. Secondary particles have a higher LET value than primary protons and are therefore expected to have a higher relative biological effectiveness (RBE). To investigate this theory, we exposed human peripheral blood lymphocytes to protons with energies of 250 MeV, 800MeV, 2 GeV, or 2.5 GeV. LET values for these protons ranged from 0.4 to 0.2 keV/µm. and doses ranged from 0.2 to 3 Gy. Over this energy range the probability of nuclear reaction leading to secondary radiation, and the multiplicity of reaction products such as neutrons and mesons increases substantially. The effect of aluminum and polyethylene shielding was also assessed using the 2 GeV and 2.5GeV proton beams. After exposure lymphocytes were stimulated to divide and chromosomes were collected from cells in the first G2 and metaphase cell cycle after exposure using a chemical induced premature chromosome condensation (PCC) technique. Dose response data for chromosome damage was analyzed using the fluorescence in situ hybridization (FISH) chromosome painting technique. Selected samples were also analyzed with multicolor FISH (mFISH) and multicolor banding FISH (mBAND) techniques. Data indicates that the dose response for simple-type exchanges is similar for proton and gamma exposure, whereas protons induce higher yields of complex exchanges that are energy dependent. RBE values will be presented for each proton energy, and the effects of shielding and possible cytogenetic signatures of proton exposure will be discussed.

  3. Biological monitoring of workers exposed to emissions from petroleum plants

    SciTech Connect

    Anderson, D.; Hughes, J.A. [BIBRA International, Surrey (United Kingdom); Cebulska-Wasilewska, A. [Institute of Nuclear Physics, Krakow (Poland)] [and others

    1996-05-01

    This paper presents some of the results from the Commission of the European Communities collaborative research program (contract number EV5V-CT92-0221), whose aim is to investigate the relationship between exposure to petroleum emissions, benzene, and induction of genetic damage in human cells. Twenty-four workers form petroleum plants in Poland and 35 unexposed controls were examined for cytogenetic effects and ras oncoprotein levels and their relationship to confounding factors (e.g., smoking habit, sex, family cancer history, and seasonal influence). Preliminary data of chromosome aberrations (CA) and sister chromatid exchanges (SCE) showed differences among sampling subgroups. In this present study, the levels of ras p21 proteins were determined and further analyses of CA, SCE, high frequency cells (HFC), and proliferative rate index (PRI) have been undertaken. Results show that the exposed group has statistically significant increases in CA, and percent of aberrant cells. There were no differences between exposed and unexposed groups in SCE, HFC, PRI, or the levels of ras p21 proteins. Smoking was found to statistically significantly affect levels of CA, percent of aberrant cells, SCE, HFC, and ras proteins. Sister chromatid exchanges were also statistically significantly sex dependent (7.5 breaks/cell for females and 6.8 breaks/cell for males). There were no statistically significant differences for CA, percent aberrant cells, SCE, HFC, or ras p21 protein levels in subgroups characterized according to cancer cases reported in the immediate family. A seasonal variability was shown with statistically significant increases in various biomarkers in the winter. Unexposed groups also showed increases due to smoking and season. The nonsmoking group individuals also showed statistically significant increases in cytogenetic damage with exposure. 21 refs., 6 figs., 6 tabs.

  4. Damage assessment in CFRP laminates exposed to impact fatigue loading

    NASA Astrophysics Data System (ADS)

    Tsigkourakos, George; Silberschmidt, Vadim V.; Ashcroft, I. A.

    2011-07-01

    Demand for advanced engineering composites in the aerospace industry is increasing continuously. Lately, carbon fibre reinforced polymers (CFRPs) became one of the most important structural materials in the industry due to a combination of characteristics such as: excellent stiffness, high strength-to-weight ratio, and ease of manufacture according to application. In service, aerospace composite components and structures are exposed to various transient loads, some of which can propagate in them as cyclic impacts. A typical example is an effect of the wind gusts during flight. This type of loading is known as impact fatigue (IF); it is a repetition of low-energy impacts. Such loads can cause various types of damage in composites: fibre breaking, transverse matrix cracking, de-bonding between fibres and matrix and delamination resulting in reduction of residual stiffness and loss of functionality. Furthermore, this damage is often sub-surface, which reinforces the need for more regular inspection. The effects of IF are of major importance due its detrimental effect on the structural integrity of components that can be generated after relatively few impacts at low force levels compared to those in a standard fatigue regime. This study utilises an innovative testing system with the capability of subjecting specimens to a series of repetitive impacts. The primary subject of this paper is to assess the damaging effect of IF on the behaviour of drilled CFRP specimens, exposed to such loading. A detailed damage analysis is implemented utilising an X-ray micro computed tomography system. The main findings suggested that at early stages of life damage is governed by o degree splits along the length of the specimens resulting in a 20% reduction of stiffness. The final failure damage scenario indicated that transverse crasks in the 90 degree plies are the main reason for complete delamination which can be translated to a 50% stiffness reduction.

  5. Health outcomes of HIV-exposed uninfected African infants

    PubMed Central

    Kourtis, Athena P.; Wiener, Jeffrey; Kayira, Dumbani; Chasela, Charles; Ellington, Sascha R.; Hyde, Lisa; Hosseinipour, Mina; van der Horst, Charles; Jamieson, Denise J.

    2015-01-01

    Objectives To evaluate severe (grade 3/4) morbidity and mortality in HIV-exposed, uninfected infants. Design Secondary data analysis of The Breastfeeding, Antiretrovirals, and Nutrition (BAN) clinical trial. Methods BAN randomized 2369 mother–infant pairs to maternal, infant, or no extended antiretroviral prophylaxis during breastfeeding. Morbidity outcomes examined were pneumonia/serious febrile illness, diarrhea/growth faltering, and malaria. Infant death was defined as neonatal (? 30 days of life), and postneonatal (31 days to 48 weeks of life). Cox proportional hazards models were used to evaluate the effect of covariates on infant morbidity and mortality. Results The rate of pneumonia/serious febrile illness was highest in the first 12 weeks (0.83/100 person-weeks) before rapidly decreasing; rates of all morbidity outcomes increased after 24 weeks. Rates of pneumonia/serious febrile illness and diarrhea/growth faltering were higher during the rainy season. Prophylactic infant cotrimoxazole significantly decreased the rates of all morbidity outcomes. White blood cell (WBC) count less than 9000/?l at birth was associated with increased diarrhea/growth faltering [adjusted hazard ratio (aHR) 1.73, P = 0.04] and malaria (aHR 2.18, P = 0.02). Low birth weight (2000–2499 g) was associated with neonatal death (aHR 12.3, P <0.001). Factors associated with postneonatal death included rainy season (aHR 4.24, P = 0.002), infant cotrimoxazole (aHR 0.48, P = 0.03), and low infant WBC count at birth (aHR 2.53, P = 0.02). Conclusion Infant morbidity rates increased after 24 weeks, when BAN infants weaned. Introduction of prophylactic cotrimoxazole was associated with reduced rates of morbidity and mortality in HIV-exposed uninfected infants. Unexpectedly, a low WBC count at birth was significantly associated with later infant morbidity and mortality in this cohort. PMID:23719347

  6. Toxicokinetics of captan and folpet biomarkers in dermally exposed volunteers.

    PubMed

    Berthet, Aurélie; Bouchard, Michèle; Vernez, David

    2012-03-01

    To better assess biomonitoring data in workers exposed to captan and folpet, the kinetics of ring metabolites [tetrahydrophthalimide (THPI), phthalimide (PI) and phthalic acid] were determined in urine and plasma of dermally exposed volunteers. A 10? mg kg(-1) dose of each fungicide was applied on 80 ?cm(2) of the forearm and left without occlusion or washing for 24 ?h. Blood samples were withdrawn at fixed time periods over the 72? h following application and complete urine voids were collected over 96 ?h post-dosing, for metabolite analysis. In the hours following treatment, a progressive increase in plasma levels of THPI and PI was observed, with peak levels being reached at 24 ?h for THPI and 10 ?h for PI. The ensuing elimination phase appeared monophasic with a mean elimination half-life (t(½) ) of 24.7 and 29.7?h for THPI and PI, respectively. In urine, time courses PI and phthalic acid excretion rate rapidly evolved in parallel, and a mean elimination t(½) of 28.8 and 29.6 ?h, respectively, was calculated from these curves. THPI was eliminated slightly faster, with a mean t(½) of 18.7 ?h. Over the 96? h period post-application, metabolites were almost completely excreted, and on average 0.02% of captan dose was recovered in urine as THPI while 1.8% of the folpet dose was excreted as phthalic acid and 0.002% as PI, suggesting a low dermal absorption fraction for both fungicides. This study showed the potential use of THPI, PI and phthalic acid as key biomarkers of exposure to captan and folpet. PMID:21381058

  7. Deciphering Genome Environment Wide Interactions Using Exposed Subjects Only.

    PubMed

    Zhao, Lue Ping; Fan, Wenhong; Goodman, Gary; Radich, Jerry; Martin, Paul

    2015-07-01

    The recent successes of genome-wide association studies (GWAS) have renewed interest in genome environment wide interaction studies (GEWIS) to discover genetic factors that modulate penetrance of environmental exposures to human diseases. Indeed, gene-environment interactions (G × E), which have not been emphasized in the GWAS era, could be a source contributing to the missing heritability, a major bottleneck limiting continuing GWAS successes. In this manuscript, we describe a design and analytic strategy to focus on G × E using only exposed subjects, dubbed as e-GEWIS. Operationally, an e-GEWIS analysis is equivalent to a GWAS analysis on exposed subjects only, and it has actually been used in some earlier GWAS without being explicitly identified as such. Through both analytics and simulations, e-GEWIS has been shown better efficiency than the usual cross-product-based analysis of G × E interaction with both cases and controls (cc-GEWIS), and they have comparable efficiency to case-only analysis of G × E (c-GEWIS), with potentially smaller sample sizes. The formalization of e-GEWIS here provides a theoretical basis to legitimize this framework for routine investigation of G × E, for more efficient G × E study designs, and for improvement of reproducibility in replicating GEWIS findings. As an illustration, we apply e-GEWIS to a lung cancer GWAS data set to perform a GEWIS, focusing on gene and smoking interaction. The e-GEWIS analysis successfully uncovered positive genetic associations on chromosome 15 among current smokers, suggesting a gene-smoking interaction. Although this signal was detected earlier, the current finding here serves as a positive control in support of this e-GEWIS strategy. PMID:25694100

  8. Fish exposed to BP oil spill 'swim slower' Study finds the speed of mahi-mahi exposed to BP's Gulf of

    E-print Network

    Grosell, Martin

    Fish exposed to BP oil spill 'swim slower' Study finds the speed of mahi-mahi exposed to BP's Gulf of Mexico oil spill has fallen 37pc The 87-day-long spill dumped an estimated 4.9m barrels of oil in the gulf shortly after the spill, which oil company BP disputed. "The study does not provide any evidence

  9. Engineering a robotic approach to mapping exposed volcanic fissures

    NASA Astrophysics Data System (ADS)

    Parcheta, C. E.; Parness, A.; Mitchell, K. L.

    2014-12-01

    Field geology provides a framework for advanced computer models and theoretical calculations of volcanic systems. Some field terrains, though, are poorly preserved or accessible, making documentation, quantification, and investigation impossible. Over 200 volcanologists at the 2012 Kona Chapman Conference on volcanology agreed that and important step forward in the field over the next 100 years should address the realistic size and shape of volcanic conduits. The 1969 Mauna Ulu eruption of K?lauea provides a unique opportunity to document volcanic fissure conduits, thus, we have an ideal location to begin addressing this topic and provide data on these geometries. Exposed fissures can be mapped with robotics using machine vision. In order to test the hypothesis that fissures have irregularities with depth that will influence their fluid dynamical behavior, we must first map the fissure vents and shallow conduit to deci- or centimeter scale. We have designed, constructed, and field-tested the first version of a robotic device that will image an exposed volcanic fissure in three dimensions. The design phase included three steps: 1) create the payload harness and protective shell to prevent damage to the electronics and robot, 2) construct a circuit board to have the electronics communicate with a surface-based computer, and 3) prototype wheel shapes that can handle a variety of volcanic rock textures. The robot's mechanical parts were built using 3d printing, milling, casting and laser cutting techniques, and the electronics were assembled from off the shelf components. The testing phase took place at Mauna Ulu, K?lauea, Hawai'i, from May 5 - 9, 2014. Many valuable design lessons were learned during the week, and the first ever 3D map from inside a volcanic fissure were successfully collected. Three vents had between 25% and 95% of their internal surfaces imaged. A fourth location, a non-eruptive crack (possibly a fault line) had two transects imaging the textures of the walls with depth to compare to the fissure vents. The vent surface irregularity documented by Parcheta et al., (accepted) continues with depth into the fissure; depths are variable depending on the amount of talus filling them. We will show and discuss data from the main field vent location, and movies of descents in to the other vents.

  10. Enhanced immunosuppression by therapy-exposed glioblastoma multiforme tumor cells.

    PubMed

    Authier, Astrid; Farrand, Kathryn J; Broadley, Kate W R; Ancelet, Lindsay R; Hunn, Martin K; Stone, Sarrabeth; McConnell, Melanie J; Hermans, Ian F

    2015-06-01

    Glioblastoma multiforme (GBM) is a highly malignant brain tumor with an extremely short time to relapse following standard treatment. Since recurrent GBM is often resistant to subsequent radiotherapy and chemotherapy, immunotherapy has been proposed as an alternative treatment option. Although it is well established that GBM induces immune suppression, it is currently unclear what impact prior conventional therapy has on the ability of GBM cells to modulate the immune environment. In this study, we investigated the interaction between immune cells and glioma cells that had been exposed to chemotherapy or irradiation in vitro. We demonstrate that treated glioma cells are more immunosuppressive than untreated cells and form tumors at a faster rate in vivo in an animal model. Cultured supernatant from in vitro-treated primary human GBM cells were also shown to increase suppression, which was independent of accessory suppressor cells or T regulatory cell generation, and could act directly on CD4(+) and CD8(+) T cell proliferation. While a number of key immunosuppressive cytokines were overexpressed in the treated cells, including IL-10, IL-6 and GM-CSF, suppression could be alleviated in a number of treated GBM lines by inhibition of prostaglandin E2. These results reveal for the first time that conventional therapies can alter immunosuppressive pathways in GBM tumor cells, a finding with important implications for the combination of immunotherapy with standard treatment. PMID:25363661

  11. Temperature and adrenocortical responses in rhesus monkeys exposed to microwaves

    SciTech Connect

    Lotz, W.G.; Podgorski, R.P.

    1982-12-01

    To determine if the endocrine response to microwave exposure was similar in a primate to that reported for other animals, rectal temperature and plasma levels of cortisol, thyroxine (T4), and growth hormone (GH) were measured in rhesus monkeys exposed to 1.29-GHz microwave radiation. Exposures were carried out under far-field conditions with the monkey restrained in a chair. Incident power densities of 0, 20, 28, and 38 mW/sq cm were used, with corresponding specific absorption rates of 0, 2.1, 3.0, and 4.1 W/kg. Blood samples were taken hourly via an indwelling jugular venous catheter over a 24-h period before, during, and after an 8-h exposure. Rectal temperature increased an average of 0.5, 0.7, and 1.7 C for the three intensities used. No changes in T4 or GH were observed. Cortisol levels were increased during exposure to 38 mW/sq cm. It was concluded that the temperature and adrenocortical responses to microwave exposure of the rhesus monkey are similar to the corresponding responses of other animals.

  12. Critical organ concentration of cadmium in occupationally-exposed workers

    SciTech Connect

    Ellis, K.J.; Morgan, W.D.; Yasumura, S.; Vartsky, D.; Zanzi, I.; Cohn, S.H.

    1981-01-01

    This report describes the present Brookhaven facility for in vivo measurements of cadmium in man and provides a comparison with other portable systems. The cadmium detection limits are 2.2 mg in the kidney and 1.5 ppM in the liver for the Brookhaven system. In a recent field study, the cadmium content of the left kidney and concentration in the liver were measured in 82 occupationally exposed workers and 10 control subjects. Organ content ranged up to 57 mg in the kidney and up to 120 ppM in the liver for the industrial group. By contrast, the values for the control group ranged from 0.4 to 11.8 mg for the kidney and 0.7 to 7.9 ppM for the liver. The geometric means were 3.7 mg for the kidney and 2.7 ppM for the liver in the control group. When the data were analyzed to provide an estimate of the critical concentration for the kidney, a range of 300 to 400 ..mu..g/g for the renal cortex was calculated. The corresponding cadmium concentrations in the liver and urine were 30 to 42 ppM (liver) and 22 to 28 ..mu..g/g creatinine (urine), respectively. Blood and urine levels of cadmium and ..beta../sub 2/-microgloubin were also evaluated as possible biological indicators of organ content.

  13. Subaerially exposed Holocene coral reef, Enriquillo Valley, Dominican Republic

    NASA Technical Reports Server (NTRS)

    Mann, P.; Taylor, F. W.; Burke, K.; Kulstad, R.

    1984-01-01

    An extremely well-preserved Holocene fringing coral reef occurs at an average elevation of 5 m below sea level around the margins of the central Enriquillo Valley, Dominican Republic. The reef records the latest marine incursion from the east into an 85-km-long, 12-km-wide tectonic depression and appears to represent a unique preservation. Excellent cross sections of the reef exposed in erosional gullies reveal a composition and zonation typical of modern Caribbean reefs that are found in offshore low-energy environments. Radiocarbon age determinations (2) indicate that reef growth coincided with sea-level rise following the last ice age (5,930 + or - 100 to 4,760 + or - 90 yr B.P.). Deltaic deposition and possible vertical movements on active fault scarps dammed the eastern mouth of the valley and created Lago Enriquillo, the level of which was then rapidly lowered by evaporation in an arid climate to produce a saline lake approximately 40 m below sea level. Stratigraphic studies of rocks along the valley edge and data from drill holes in the basin center indicate that there were earlier post-Miocene marine incursions similar to that described here.

  14. Transcriptomic and proteomic profiling of maize embryos exposed to camptothecin

    PubMed Central

    2011-01-01

    Background Camptothecin is a plant alkaloid that specifically binds topoisomerase I, inhibiting its activity and inducing double stranded breaks in DNA, activating the cell responses to DNA damage and, in response to severe treatments, triggering cell death. Results Comparative transcriptomic and proteomic analyses of maize embryos that had been exposed to camptothecin were conducted. Under the conditions used in this study, camptothecin did not induce extensive degradation in the genomic DNA but induced the transcription of genes involved in DNA repair and repressed genes involved in cell division. Camptothecin also affected the accumulation of several proteins involved in the stress response and induced the activity of certain calcium-dependent nucleases. We also detected changes in the expression and accumulation of different genes and proteins involved in post-translational regulatory processes. Conclusions This study identified several genes and proteins that participate in DNA damage responses in plants. Some of them may be involved in general responses to stress, but others are candidate genes for specific involvement in DNA repair. Our results open a number of new avenues for researching and improving plant resistance to DNA injury. PMID:21595924

  15. Hydrophobicity, Adhesion, and Surface-Exposed Proteins of Gliding Bacteria

    PubMed Central

    Sorongon, Maria L.; Bloodgood, Robert A.; Burchard, Robert P.

    1991-01-01

    The cell surface hydrophobicities of a variety of aquatic and terrestrial gliding bacteria were measured by an assay of bacterial adherence to hydrocarbons (BATH), hydrophobic interaction chromatography, and the salt aggregation test. The bacteria demonstrated a broad range of hydrophobicities. Results among the three hydrophobicity assays performed on very hydrophilic strains were quite consistent. Bacterial adhesion to glass did not correlate with any particular measure of surface hydrophobicity. Several adhesion-defective mutants of Cytophaga sp. strain U67 were found to be more hydrophilic than the wild type, particularly by the BATH assay and hydrophobic interaction chromatography. The very limited adhesion of these mutants correlated well with hydrophilicity as determined by the BATH assay. The hydrophobicities of several adhesion-competent revertants ranged between those of the wild type and the mutants. As measured by the BATH assay, starvation increased hydrophobicity of both the wild type and an adhesion-defective mutant. During filament fragmentation of Flexibacter sp. strain FS-1, marked changes in hydrophobicity and adhesion were accompanied by changes in the arrays of surface-exposed proteins as detected by an immobilized radioiodination procedure. Images PMID:16348583

  16. Response of bush bean exposed to acid mist

    SciTech Connect

    Hindawi, I.J.; Rea, J.A.; Griffis, W.L.

    1980-01-01

    Bush bean plants (Phaseolus vulgaris l. Cv. contender) were treated once a week for six weeks with simulated acid mist at five pH levels ranging from 5.5 to 2.0. Leaf injury developed on plants exposed to acid concentrations below pH 3 and many leaves developed a flecking symptom similar to that caused by ozone. An adaxial, interveinal bleached area resembling SO/sub 2/ injury also developed on some trifoliate leaves at the low pH treatments. Microscopic observation of injured trifoliates indicated that the pallisade cells were plasmolyzed and that the chloroplasts lost structural integrity. Reductions in plant weight and chlorophyll content were detected across the pH gradient. Seed and pod growth were reduced at some intermediate acid depositions even though no visible foliar injury developed. Foliar losses of nitrogen, calcium, magnesium and phosphorous increased with decreases in acid mist pH, whereas foliar potassium concentrations were unaffected by acid mist treatment.

  17. Cancer mortality among petroleum-solvent-exposed Oklahoma dry cleaners

    SciTech Connect

    Petrone, R.L.

    1987-01-01

    This study assesses the solvent specific influence on the proportionate mortality occurring among white males with exposures to petroleum solvents, averaging 10.5 years, and were without known exposure to synthetic solvents. No excess in overall cancer mortality, or in any major noncancer cause of death was found. The proportionate mortality ration (PMR) for All malignant neoplasms was 1.04 and was independent of latency and years of exposure. No excess in overall cancer deaths was found to occur in cohort members dying before age 65. A significant excess in respiratory system cancer was detected, with all excesses occurring among those who died at age 65 and older. No relationship was noted to years of latency or years of exposure. A PMR of 1.96 for pancreatic cancer was noted with three of nine deaths occurring among men younger than age 65. Consistent elevations if PMRs were seen for all categories of duration of exposure greater than 5-9 years. No pancreatic cancer deaths occurred with less than 20 years of latency. Excesses found for kidney cancer among the entire cohort were lost when only petroleum solvent exposed white males were analyzed. The power to detect an excess or deficit in overall or site-specific cancer deaths was adequate at relative risk of four or less for most cancer sites of interest.

  18. Byssinosis in carpet weavers exposed to wool contaminated with endotoxin.

    PubMed

    Ozesmi, M; Aslan, H; Hillerdal, G; Rylander, R; Ozesmi, C; Baris, Y I

    1987-07-01

    All the 303 full time day workers in a carpet weaving factory were submitted to a physical examination, chest radiography, and vitalograph test, and answered a respiratory questionnaire. Fifty four healthy non-exposed subjects served as controls. Dust concentrations and concentrations of bacterial endotoxin were measured. Of the 303 workers, 259 (85.5%) had airway symptoms and 62 (20.5%) had maximum mid-expiratory flow (MMF) values of less than 60% compared with 9.2% of the controls. The symptoms in 68 workers (22%) were compatible with byssinosis and 36 of these workers underwent vitalography before starting work and after four hours work on Mondays when significant reductions of their FEV1 and MMF were found. Twenty one of these 36 workers were tested on Tuesday and no differences in these measurements were found between measurements before work started and four hours later. The airborne dust concentrations in the factory were high and bacterial endotoxin was found. These findings suggest that a large number of workers in this carpet weaving factory suffer from a disease indistinguishable from byssinosis even though wool is used almost exclusively, the only cotton being the warp. The finding of endotoxin together with the absence of cotton confirms the theory that "byssinosis" is due to bacterial endotoxin rather than to cotton per se. PMID:3620372

  19. Oxidative damage in various tissues of rats exposed to radon.

    PubMed

    Nie, Ji-Hua; Chen, Zhi-Hai; Liu, Xing; Wu, Yan-Wen; Li, Ji-Xiang; Cao, Yi; Hei, Tom K; Tong, Jian

    2012-01-01

    Oxidative damage can be induced by many environmental stressors. 8-Hydroxydeoxyguanosine (8-OHdG) has been used as a biomarker of oxidative DNA damage in both in vitro and in vivo studies. In the present study, Wistar rats were exposed to radon gas at a concentration of 100,000Bq/m(3) for 12 h/d for 30, 60, and 120 d, equivalent to cumulative doses of 60, 120, and 240 working level months (WLM), respectively. Changes in levels of 8-OHdG, reactive oxygen species (ROS), and total antioxidant (T-AOC), as well as expressions of some DNA repair enzymes such as 8-oxoguanine DNA glycosylase (OGG1) and MutT homolog 1 (oxidized purine nucleoside triphosphatase, MTH1), were determined in rat urine, peripheral blood lymphocytes, and lung after exposure to radon. The results revealed an increase in 8-OHdG and ROS levels, a decrease in T-AOC levels, and reduced OGG1 and MTH1 expression levels. The elevated amount of 8-OHdG in urine or lymphocytes was positively correlated with the cumulative exposure dose, whereas OGG1 and MHT1 expression levels in lung were inversely correlated with cumulative exposure dose. These findings indicate that oxidative damage induced by radon may be involved in radon-induced carcinogenesis. PMID:22757673

  20. Synthesis of protein in intestinal cells exposed to cholera toxin

    SciTech Connect

    Peterson, J.W.; Berg, W.D. Jr.; Coppenhaver, D.H.

    1987-11-01

    The mechanism by which cyclic adenosine monophosphate (AMP), formed by intestinal epithelial cells in response to cholera toxin, ultimately results in alterations in water and electrolyte transport is poorly understood. Several studies have indicated that inhibitors of transcription or translation block much of the transport of ions and water in the intestine and edema formation in tissue elicited by cholera toxin. Data presented in this study confirmed the inhibitory effects of cycloheximide on cholera toxin-induced fluid accumulation in the rabbit intestinal loop model. Neither cycloheximide nor actinomycin D altered the amount of cyclic AMP that accumulated in intestinal cells and Chinese hamster ovary cells exposed to cholera toxin. An increase in (/sup 3/H) leucine incorporation was readily demonstrable in intestinal epithelial cells from rabbits challenged with Vibrio cholerae. Similarly, intestinal epithelial cells incubated with cholera toxin for 4 hr synthesized substantially more protein than controls as determined by relative incorporation of (/sup 35/S) methionine. Most of the new protein synthesized in response to cholera toxin was membrane associated and of high molecular weight. The possible significance of the toxin-induced protein relative to cholera pathogenesis was discussed.

  1. Melatonin protects uterus and oviduct exposed to nicotine in mice

    PubMed Central

    Saadat, Seyedeh Nazanin Seyed; Jahromi, Sina Khajeh; Homafar, Mohammad Amin; Haghiri, Mostafa

    2014-01-01

    Smoking is associated with higher infertility risk. The aim of this study was to evaluate protective effects of melatonin on the uterus and oviduct in mice exposed to nicotine. Adult female mice (n=32) were divided into four groups. Group A: control animals received normal saline, Group B: injected with nicotine 40µg/kg, Group C: injected with melatonin 10 µg, Group D: injected with nicotine 40µg/kg and melatonin 10 µg. All animals were treated over 15 days intraperitoneally. On the 16th day, animals in the estrus phase were dissected and their uterus and oviducts were removed. Immunohistochemistry was recruited for studying apoptosis and for detection of estrogen receptor (ER) alpha in luminal epithelium of the uterus and oviduct. Enzyme-linked immunosorbent assay was used for serum estradiol level determination. Nicotine in group B decreased estradiol level and ERalpha numbers both in the uterus and oviduct (p<0.05). Co-administration of melatonin-nicotine in Group D ameliorated the histology of the uterus and oviduct, increased ERalpha numbers and reduced apoptosis in the uterus and oviduct compared with the nicotine Group B (p<0.05). This study indicates that nicotine impairs the histology of the uterus and oviduct and co-administration of melatonin-nicotine ameliorates these findings, partly through alteration in ERalpha numbers and reduction of apoptosis.

  2. Exposing Middle School Students to Remote Sensing in Alaska

    NASA Astrophysics Data System (ADS)

    Prakash, A.

    2003-12-01

    The need for attracting young minds to scientific research at an early stage is already recognized. Efforts are underway by major organizations to inspire the next generation of scientists. To be effective, there is a need to exploit the potential of the World Wide Web and bring it to a status that printed media have already reached. We find series of theme oriented books for children but websites with such stories are few and scattered. NASA's efforts in generating remote sensing based web stories such as the 'Adventures of Amelia the Pigeon' and 'Echo the Bat' are very good examples and starting points for generating more theme based material for children. 'Alaska: A Bird's Eye View' is a web-based story, specifically designed for grade 5-8 students. The story that is told by a Canada Goose exposes children to the truths of the remote State of Alaska and to the potential of satellite remote sensing. Examples on use remote sensing for monitoring volcanoes and sea ice edge dynamics are related to children in simple and effective ways. The topic of global climate change and its effect on marine animals has also been introduced to children.

  3. Reproductive effects in birds exposed to pesticides and industrial chemicals

    SciTech Connect

    Fry, D.M. [Univ. of California, Davis, CA (United States)

    1995-10-01

    Environmental contamination by agricultural chemicals and industrial waste disposal results in adverse effects on reproduction of exposed birds. The diversity of pollutants results in physiological effects at several levels, including direct effects on breeding adults as well as developmental effects on embryos. The effects on embryos include mortality or reduced hatchability, failure of chicks to thrive (wasting syndrome), and teratological effects producing skeletal abnormalities and impaired differentiation of the reproductive and nervous systems through mechanisms of hormonal mimicking of estrogens. The range of chemical effects on adult birds covers acute mortality, sublethal stress, reduced fertility, suppression of egg formation, eggshell thinning, and impaired incubation and chick rearing behaviors. The types of pollutants shown to cause reproductive effects include organochlorine pesticides and industrial pollutants, organophosphate pesticides, petroleum hydrocarbons, heavy metals, and in a fewer number of reports, herbicides, and fungicides. o,p`-DDT, polychlorinated biphenyls (PCBs), and mixtures of organochlorines have been identified as environmental estrogens affecting populations of gulls breeding in polluted {open_quotes}hot spots{close_quotes} in southern California, the Great Lakes, and Puget Sound. Estrogenic organochlorines represent an important class of toxicants to birds because differentiation of the avian reproductive system is estrogen dependent. 85 refs.

  4. Immunomodulatory effects of nanocurcumin in arsenic-exposed rats.

    PubMed

    Sankar, Palanisamy; Telang, Avinash Gopal; Suresh, Subramaniyam; Kesavan, Manickam; Kannan, Kandasamy; Kalaivanan, Ramya; Sarkar, Souvendra Nath

    2013-09-01

    We evaluated whether the nanoformulation of curcumin could be more effective than free curcumin against arsenic-induced immune dysfunction in rats. Curcumin was encapsulated in polylactic-co-glycolic acid (PLGA). Nanocurcumin (CUR-NP) exhibited a spherical shape with the mean particle size of 130.8 nm. Rats were randomly divided into five groups of six each. Group I was kept as the control. In Group II, rats were exposed to sodium arsenite (25 ppm) daily through drinking water for 42 days. Groups III, IV and V were treated with arsenic as in Group II, however, they were administered with nanoparticle, curcumin (100 mg/kg bw) and CUR-NP (100 mg/kg bw), respectively, by oral gavage during the last 14 days of arsenic exposure. At term, serum and spleen were collected. Immune dysfunction was evaluated by assessing cellular and humoral immunities. Arsenic significantly decreased the splenic lymphocyte proliferation in response to the antigen -- Keyhole Limpet Hemocyanin (KLH) and mitogen -- concanavalin-A. Arsenic reduced both the delayed type hypersensitivity response and secondary antibody (IgG) response to KLH. It also reduced the lipopolysaccharide-stimulated nitric oxide production in splenic lymphocytes. Free curcumin and CUR-NP treatment significantly attenuated these arsenic-mediated effects. However, the magnitude of the effects indicates that CUR-NP has better ameliorative potential than free curcumin at the equivalent dose level. PMID:23747587

  5. RADIOLYTIC GAS PRODUCTION RATES OF POLYMERS EXPOSED TO TRITIUM GAS

    SciTech Connect

    Clark, E.

    2013-08-31

    Data from previous reports on studies of polymers exposed to tritium gas is further analyzed to estimate rates of radiolytic gas production. Also, graphs of gas release during tritium exposure from ultrahigh molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, a trade name is Teflon®), and Vespel® polyimide are re-plotted as moles of gas as a function of time, which is consistent with a later study of tritium effects on various formulations of the elastomer ethylene-propylene-diene monomer (EPDM). These gas production rate estimates may be useful while considering using these polymers in tritium processing systems. These rates are valid at least for the longest exposure times for each material, two years for UHMW-PE, PTFE, and Vespel®, and fourteen months for filled and unfilled EPDM. Note that the production “rate” for Vespel® is a quantity of H{sub 2} produced during a single exposure to tritium, independent of length of time. The larger production rate per unit mass for unfilled EPDM results from the lack of filler- the carbon black in filled EPDM does not produce H{sub 2} or HT. This is one aspect of how inert fillers reduce the effects of ionizing radiation on polymers.

  6. Coating concrete secondary containment structures exposed to agrichemicals

    SciTech Connect

    Broder, M.F.; Nguyen, D.T.

    1995-06-01

    Concrete has traditionally been the material of choice for building secondary containment structures because it is relatively inexpensive and has structural properties which make it ideal for supporting the loads of vehicles and large tanks. However, concrete`s chemical properties make it susceptible to corrosion by some common fertilizers. Though fairly impervious to water movement, concrete is easily penetrated by vapors and solvents. It is also prone to cracking. For these reasons, the Environmental Protection Agency (EPA) believes that concrete alone may not provide an effective barrier to pesticide movement and has proposed that concrete in pesticide secondary containment structures be sealed or coated to reduce its permeability. Some state secondary containment regulations require that concrete exposed to fertilizers and pesticides be sealed or protected with a coating. Lacking guidelines, some retailers have used penetrating sealants to satisfy the law, even though these products provide little protection from chemical attack nor do they prevent pesticide egress. Other retailers who have applied thick film coatings which were properly selected have had disastrous results because the application was poorly done. Consequently, much skepticism exists regarding the performance and benefit of protective coatings.

  7. Impairment of colour vision in workers exposed to organic solvents

    PubMed Central

    Semple, S; Dick, F; Osborne, A; Cherrie, J; Soutar, A; Seaton, A; Haites, N

    2000-01-01

    OBJECTIVES—To investigate loss of colour vision related to exposure to solvents and the role of three enzyme polymorphisms in modifying the risk in exposed workers.?METHODS—A sample was studied of 68 male dockyard workers and 42 male community controls with and without neuropsychological symptoms from a previous cross sectional study. Indices of cumulative and intensity based exposure to solvents were calculated for all subjects. Alcohol, drug, and smoking histories were obtained. Colour vision was tested by Lanthony D15d colour vision test. Genotype of glutathione S-transferase M1 and T1 and N-acetyltransferase 2 polymorphisms were determined.?RESULTS—The relation between impairment of colour vision and exposure to solvents was investigated with multiple regression techniques. Increasing annual exposure to solvents was significantly associated with reduced colour vision (p=0.029). Impairment of colour vision was not associated with neuropsychological symptoms as measured by the Q16 solvent symptom questionnaire. No significant association was found between acquired impairment of colour vision and genetic polymorphisms when GSTM1, GSTT1 or NAT2 phenotypes were included in the analyses.?CONCLUSIONS—Exposure to mixed solvents is associated with impairment in colour vision, the risk increases with increasing exposure. The risk of impairment of colour vision was not altered in this study by the presence of different GSTM1, GSTT1 or NAT2 polymorphisms.???Keywords: colour vision; organic solvents; genetic polymorphisms PMID:10935938

  8. [Dosage indicators in farm workers exposed to mancozeb].

    PubMed

    Canossa, E; Angiuli, G; Garasto, G; Buzzoni, A; De Rosa, E

    1993-01-01

    A study was performed on a group of farm workers exposed to mancozeb to validate dose indicators. Two indirect methods have been employed to monitor the air-dispersed mancozeb in the working environment (average concentration 57.2 micrograms/Nm3): carbon disulfide and manganese dosage. The latter proved to be more applicable. To assess skin contamination, the concentration of mancozeb was measured on pads placed on work overalls and in the liquid employed to wash workers' hands. Average concentrations of 0.86 microgram/cm2 and 641 micrograms respectively were obtained. A good correlation between mancozeb concentration on pads and in the air was found. Urinary ethylenethiourea (ETU) and manganese measured before and after a three day exposure were selected as indicators for internal dose. In all cases except three (2.9-2.3 and 4.4 mg/g creat.) ETU was below the sensitivity limit of the method employed. Urinary manganese increased from a mean of 0.32 microgram/g creat. to a mean of 0.53 microgram/g creat. after the exposure. The correlation with environmental data was r = 0.667. PMID:8492735

  9. Physiological and antioxidant responses of Salvinia natans exposed to chromium-rich wastewater

    Microsoft Academic Search

    Bhupinder Dhir; P. Sharmila; P. Pardha Saradhi; Sekh Abdul Nasim

    2009-01-01

    Salvinia natans possess capacity to accumulate high concentrations of chromium (Cr). Studies were carried out to evaluate physiological efficiency and defensive potential of plant exposed to Cr-rich wastewater. Among photochemical reactions, photosystem I (PS I) and photosystem II (PS II) activity noted an increase in plants exposed to Cr-rich wastewater. Fluorescence ratio Fv\\/Fm depicted no alteration in plants exposed to

  10. Electrophoresis pattern of serum from mice exposed to different concentrations of sulfur dioxide

    NASA Technical Reports Server (NTRS)

    Singh, J.

    1977-01-01

    Three day old mice were continuously exposed to sulphur dioxide concentrations at 0ppm, 0.05ppm, 0.15ppm and 1ppm for eight weeks. At the end of the experiment, blood samples were collected and centrifuged for electrophoresis studies of the serum in 5 percent acrylamide gel. The length of bands of different serum proteins from the SO2 exposed mice was at a variance as compared with the length of bands from the control exposed mice and alpha-1 band seems to be missing from the serum of SO2 exposed mice.

  11. Evaluation of selenium in biological sample of arsenic exposed female skin lesions and skin cancer patients with related to non-exposed skin cancer patients.

    PubMed

    Kolachi, Nida F; Kazi, Tasneem G; Wadhwa, Sham K; Afridi, Hassan I; Baig, Jameel A; Khan, Sumaira; Shah, Faheem

    2011-08-01

    The antagonistic effects between selenium (Se) and arsenic (As) suggest that low Se status plays an important role in arsenism development. The objective of present study was to assess Se contents in biological samples of As exposed females have skin lesions and cancer with related to non-exposed skin cancer patients. The biological samples (blood and scalp hair) of As exposed group comprises, female skin cancer (ESC) patients admitted in cancer hospitals have skin lesions (ESL) and exposed referents have not both diseases (ER), belongs to As exposed area of Pakistan. For comparative purposes, age matched female skin cancerous patient (RP) and non-cancerous females (NER) belong to non-exposed areas were also selected. The As and Se in acid digests of biological samples were pre-concentrated by complexing with chelating agent (ammonium pyrrolidinedithiocarbamate), and resulted complexes were extracted into non-ionic extractant (Triton X-114), prior to analysis by electrothermal atomic absorption spectrometry. The enhancement factor of about 25 was obtained by pre-concentrating 10 mL of sample solutions. The accuracy of the optimized procedure was evaluated by using certified reference material (BCR 397) with certified values for Se and As and standard addition method at three concentration levels in real samples. No significant differences was observed (p>0.05) when comparing the values obtained by the proposed method, added and certified values of both elements. The biological samples of ESC patients had 2-3 folds higher As and lower Se levels as compared to RP (p<0.001). Understudied exposed referents have high level of As and lower Se contents as compared to referents subjects of non-exposed area (p<0.01). The higher concentration of As and lower levels of Se in biological samples of cancerous patients are consisted with reported studies. PMID:21624640

  12. Semen quality in welders exposed to radiant heat.

    PubMed Central

    Bonde, J P

    1992-01-01

    Several studies suggest that welding is detrimental to the male reproductive system. Welding fume and radiant heat are of interest as possible causal factors. This study investigates semen quality and sex hormone concentrations among 17 manual metal arc alloyed steel welders with a moderate exposure to radiant heat (globe temperature ranging from 31.1 degrees to 44.8 degrees C), but without substantial exposure to welding fume toxicants. During exposure to heat the skin temperature in the groin increased on average by 1.4 degrees C (SE +/- 0.72 degrees C). Sperm count and motile sperm count were non-significantly reduced among welders in comparison with two different reference groups. Within the group of welders the proportion of sperm with normal shape declined significantly after six weeks of exposure to heat and increased after a break in exposure. Sperm count and sperm concentration had the same pattern of intraindividual change in relation to exposure to radiant heat, but the changes were not statistically significant. No consistent changes in concentrations of sex hormones were found. The welders investigated were more exposed to radiant heat than welders in general. The results suggest that the study group of welders experienced a reversible decrease in semen quality, most likely caused by a moderate exposure to radiant heat (about five hours a day through several weeks). It remains to be established if even lower levels of exposure to radiant heat in the general population of welders has any impact on semen quality and fertility. Images PMID:1733456

  13. Albumin adducts in plasma from workers exposed to toluene diisocyanate.

    PubMed

    Lind, P; Dalene, M; Lindström, V; Grubb, A; Skarping, G

    1997-02-01

    Desalted plasma from a 2,4- and 2,6-toluene diisocyanate (2,4- and 2,6-TDI) exposed worker at a factory producing flexible polyurethane foam was separated and fractionated into 200 fractions using ion-exchange chromatography followed by a gel-filtration separation and fractionation into 59 fractions. The corresponding amines (to the isocyanates), 2,4- and 2,6-toluenediamine (2,4- and 2,6-TDA), were determined in each fraction after sulfuric acid hydrolysis as pentafluoropropionic anhydride derivatives by capillary gas chromatography and chemical ionisation mass spectrometry monitoring negative ions. The ion exchange fractions containing TDA (81-115) were added together and the solution was separated and fractionated on the gel-filtration column. The fractions 81-115 contained 84 and 72% of 2,4- and 2,6-TDA, respectively, as compared to the unfractionated plasma. The gel filtration fractions 22-27 contained 107 and 119% of 2,4- and 2,6-TDA, respectively, as compared to the amounts in the ion exchange fractions (81-115). Agarose gel-electrophoresis and electroimmunoassay demonstrated that albumin, 2,4- and 2,6-TDA co-eluted in both ion-exchange and gel-filtration chromatography. Quantitative determination of albumin, 2,4- and 2,6-TDA also demonstrated that these components co-eluted using albumin-immunosorption chromatography. In addition, studies of affinity isolated IgG revealed that this fraction was devoid of 2,4- and 2,6-TDA. These results indicate that albumin is the major receptor molecule for 2,4- and 2,6-TDI in blood plasma and that these isocyanates form covalent bondings with albumin. PMID:9124697

  14. Types of rocks exposed at the Viking landing sites

    SciTech Connect

    Guinness, E.; Arvidson, R.; Dale-Bannister, M.; Slavney, S.

    1985-01-01

    Spectral estimates derived from Viking Lander multispectral images have been used to investigate the types of rocks exposed at both landing sites, and to infer whether the rocks are primary igneous rocks or weathering products. These analyses should aid interpretations of spectra to be returned from the Visual and Infrared Mapping Spectrometer on the upcoming Mars Observer Mission. A series of gray surfaces on the Landers were used to check the accuracy of the camera preflight calibrations. Results indicate that the pre-flight calibrations for the three color channels are probably correct for all cameras but camera 2 on Lander 1. The calibration for the infrared channels appears to have changed, although the cause is not known. For this paper, only the color channels were used to derive data for rocks. Rocks at both sites exhibit a variety of reflectance values. For example, reflectance estimates for two rocks in the blue (0.4-0.5 microns), green (0.5-0.6 microns), and red (0.6-0.75 microns) channels are 0.16, 0.23, and 0.33 and 0.12, 0.19, 0.37 at a phase angle of 20 degrees. These values have been compared with laboratory reflectance spectra of analog materials and telescopic spectra of Mars, both convolved to the Lander bandpasses. Lander values for some rocks are similar to earth based observations of martian dark regions and with certain mafic igneous rocks thinly coated with amorphous ferric-oxide rich weathering products. These results are consistent with previous interpretations.

  15. Hippocampal phosphoproteomics of F344 rats exposed to 1-bromopropane.

    PubMed

    Huang, Zhenlie; Ichihara, Sahoko; Oikawa, Shinji; Chang, Jie; Zhang, Lingyi; Hu, Shijie; Huang, Hanlin; Ichihara, Gaku

    2015-01-15

    1-Bromopropane (1-BP) is neurotoxic in both experimental animals and human. To identify phosphorylated modification on the unrecognized post-translational modifications of proteins and investigate their role in 1-BP-induced neurotoxicity, changes in hippocampal phosphoprotein expression levels were analyzed quantitatively in male F344 rats exposed to 1-BP inhalation at 0, 400, or 1000 ppm for 8 h/day for 1 or 4 weeks. Hippocampal protein extracts were analyzed qualitatively and quantitatively by Pro-Q Diamond gel staining and SYPRO Ruby staining coupled with two-dimensional difference in gel electrophoresis (2D-DIGE), respectively, as well as by matrix-assisted laser-desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) to identify phosphoproteins. Changes in selected proteins were further confirmed by Manganese II (Mn(2+))-Phos-tag SDS-polyacrylamide gel electrophoresis (SDS-PAGE). Bax and cytochrome c protein levels were determined by western blotting. Pro-Q Diamond gel staining combined with 2D-DIGE identified 26 phosphoprotein spots (p<0.05), and MALDI-TOF/MS identified 18 up-regulated proteins and 8 down-regulated proteins. These proteins are involved in the biological process of response to stimuli, metabolic processes, and apoptosis signaling. Changes in the expression of phosphorylated 14-3-3 ? were further confirmed by Mn(2+)-Phos-tag SDS-PAGE. Western blotting showed overexpression of Bax protein in the mitochondria with down-regulation in the cytoplasm, whereas cytochrome c expression was high in the cytoplasm but low in the mitochondria after 1-BP exposure. Our results suggest that the pathogenesis of 1-BP-induced hippocampal damage involves inhibition of antiapoptosis process. Phosphoproteins identified in this study can potentially serve as biomarkers for 1-BP-induced neurotoxicity. PMID:25448045

  16. (1)H NMR brain metabonomics of scrapie exposed sheep.

    PubMed

    Scano, Paola; Rosa, Antonella; Incani, Alessandra; Maestrale, Caterina; Santucciu, Cinzia; Perra, Daniela; Vascellari, Sarah; Pani, Alessandra; Ligios, Ciriaco

    2015-06-16

    While neurochemical metabolite modifications, determined by different techniques, have been diffusely reported in human and mice brains affected by transmissible spongiform encephalopathies (TSEs), this aspect has been little studied in the natural animal hosts with the same pathological conditions so far. Herein, we investigated, by high resolution (1)H NMR spectroscopy and multivariate statistical data analysis, the brain metabolite profile of sheep exposed to a scrapie agent in a naturally affected flock. On the basis of clinical examinations and western blotting analysis for the pathological prion protein (PrP(Sc)) in brain tissues, sheep were catalogued as not infected (H), infected with clinical signs (S), and infected without clinical signs (A). By discriminant analysis of spectral data, comparing S vs. H, we found a different metabolite distribution, with inosine, cytosine, creatine, and lactate being higher in S than in H brains, while the branched chain amino acids (leucine, isoleucine, and valine), phenylalanine, uracil, tyrosine, gamma-amino butyric acid, total aspartate (aspartate + N-acetyl aspartate) being lower in S. By a soft independent modelling of class analogy approach, 1 out of 3 A samples was assigned to class H. Furthermore, A brains were found to be higher in choline and choline-containing compounds. By means of partial least squares regression, an excellent correlation was found between the PrP(Sc) amount and the (1)H NMR metabolite profile of infected (S and A) sheep, and the metabolite mostly correlated with PrP(Sc) was alanine. The overall results, obtained using different chemometric tools, were able to describe a brain metabolite profile of infected sheep with and without clinical signs, compared to healthy ones, and indicated alanine as a biomarker for PrP(Sc) amounts in scrapie brains. PMID:25959287

  17. Serum Matrix Metalloproteinase Levels in Patients Exposed to Sulfur Mustard

    PubMed Central

    Shohrati, Majid; Haji Hosseini, Reza; Esfandiari, Malek Ashtar; Najafian, Nastaran; Najafian, Bita; Golbedagh, Abbas

    2014-01-01

    Background: Matrix metalloproteinases (MMPs) are a group of endopeptidases which comprised of various types. These proteolytic enzymes are zinc-dependent and play role in degradation of extracellular matrix (ECM). Various types of cells such as macrophages, fibroblasts, neutrophils, synovial cells and some epithelial cells secrete MMPs. According to previous studies on bronchiolitis and respiratory tract lesions in these patients and unknown pathophysiology mechanism up to date, this cross–sectional study was performed. Objectives: The aim of this study was to compare the serum MMP level in patients with chemical injuries and normal people and also determine the role of these parameters in pulmonary disorders . Materials and Methods: In this cross–sectional study, 25 Iranian patients exposed to the sulfur mustard and 25 unexposed participants as the control group were enrolled. Serum samples were collected from two groups and stored at -70?C until the measurement of MMPs and TIMPs. ELISA kit was used for measurement of MMP and TIMP based on the kit's instruction. For validations in measurement, all samples were analyzed duplicate and in some cases triplicate. Results: The mean level of MMP-9 in serum of chemically-injured group was 1592.42 and this amount in normal group was 679.72 .So there was a significant difference between two groups (P = 0.001) and the mean level of MMP-8 in serum of patients group was 49.10 and in normal group was 35.53. Then there was no significant difference between two groups (P = 0.197). The mean levels of MMP-1 and MMP-2 was not significantly different (P value > 0.05) in the patient and normal groups. And also the mean levels of TIMP-1 and TIMP-2 was not significantly different (P > 0.05) in the patients and normal groups. Conclusions: In summary, serum MMPs in chemically-injured has shown no significant difference with normal people except for the MMP-9. PMID:24829780

  18. Deaths and tumours among rotogravure printers exposed to toluene.

    PubMed Central

    Svensson, B G; Nise, G; Englander, V; Attewell, R; Skerfving, S; Möller, T

    1990-01-01

    A cohort of 1020 rotogravure printers exposed to toluene and employed for a minimum period of three months in eight plants during 1925-85 was studied. Air levels of toluene were available since 1943 in one plant and since 1969 in most. Based on these measurements and on present concentrations of toluene in blood and subcutaneous fat, the yearly average air levels in each plant were estimated. They reached a maximum of about 450 ppm in the 1940s and 1950s but were only about 30 ppm by the mid-1980s. Exposure to benzene had occurred up to the beginning of the 1960s. Compared with regional rates, total mortality did not increase during the observation period 1952-86 (129 observed deaths v 125 expected; SMR = 1.03). There was no increase in mortality from non-malignant diseases of the lungs, nervous system, or gastrointestinal and urinary tracts. There was no overall excess of tumours 1958-85 (68 v 54, SMR = 1.26; 95% confidence interval, CI = 0.95-1.7). Among the specific cancers, only those of the respiratory tract were significantly increased (16 v 9; SMR = 1.76, CI = 1.03-2.9). Statistical significance was not attained, however, when only subjects with an exposure period of at least five years and a latency period of at least 10 years were considered. Further, there were no dose response relations with cumulated toluene dose (ppm years). There were no significant increases of tumours at other sites, including leukaemias/lymphomas/myelomas. PMID:2378814

  19. Toxicogenetic monitoring in urban cities exposed to different airborne contaminants.

    PubMed

    Pereira, Tatiana S; Beltrami, Laiana S; Rocha, Jocelita A V; Broto, Francesc P; Comellas, Lluis R; Salvadori, Daisy M F; Vargas, Vera M F

    2013-04-01

    Microparticles found in the air may be associated with organic matter that contains several compounds, such as Polycyclic Aromatic Hydrocarbons (PAHs) and nitro-PAHs, and may pose a significant risk to human health, possibly leading to DNA mutations and cancers. This study associated genotoxicity assays for evaluating human exposure with the atmospheric air of two urban areas in southern Brazil, that received different atmospheric contributions. Site 1 was under urban-industrial influence and the other was a non-industrial reference, Site 2. Organic extracts from the airborne particulate matter were tested for mutagenicity via the Salmonella/microsome assay and analyzed for PAH composition. Cells samples of people residing in these two cities were evaluated using the comet and micronucleus assay (MN).Concentrations of the individual PAHs ranged from 0.01 ng/m(3) (benzo[a]anthracene) to 5.08 ng/m(3) (benzo[ghi]perylene). As to mutagenicity analysis of airborne, Site 1 presented all the mutagenic responses, which varied from 3.2±1.22 rev/m(3) (TA98 no S9) to 32.6±2.05 rev/m(3) (TA98, S9), while Site 2 ranged from negative to minimal responses. Site 1 presented a high quantity of nitro and amino derivatives of PAHs, and peaked at 56.0±3.68 rev/?g (YG1024 strain). The two groups presented very low DNA damage levels without intergroup difference. Although Site 1 presented high mutagenic responses in the air samples, high PAH levels, healthy people exposed to this environment did not show significative damage in their genetic material. However, the evaluation of different environmental and genetic damage in such population is necessary to monitor possible damages. PMID:23395453

  20. Estimated daily intake of phthalates in occupationally exposed groups.

    PubMed

    Hines, Cynthia J; Hopf, Nancy B N; Deddens, James A; Silva, Manori J; Calafat, Antonia M

    2011-01-01

    Improved analytical methods for measuring urinary phthalate metabolites have resulted in biomarker-based estimates of phthalate daily intake for the general population, but not for occupationally exposed groups. In 2003-2005, we recruited 156 workers from eight industries where materials containing diethyl phthalate (DEP), dibutyl phthalate (DBP), and/or di(2-ethylhexyl) phthalate (DEHP) were used as part of the worker's regular job duties. Phthalate metabolite concentrations measured in the workers' end-shift urine samples were used in a simple pharmacokinetic model to estimate phthalate daily intake. DEHP intake estimates based on three DEHP metabolites combined were 0.6-850??g/kg/day, with the two highest geometric mean (GM) intakes in polyvinyl chloride (PVC) film manufacturing (17??g/kg/day) and PVC compounding (12??g/kg/day). All industries, except phthalate manufacturing, had some workers whose DEHP exposure exceeded the U.S. reference dose (RfD) of 20??g/kg/day. A few workers also exceeded the DEHP European tolerable daily intake (TDI) of 50??g/kg/day. DEP intake estimates were 0.5-170??g/kg/day, with the highest GM in phthalate manufacturing (27??g/kg/day). DBP intake estimates were 0.1-76??g/kg/day, with the highest GMs in rubber gasket and in phthalate manufacturing (17??g/kg/day, each). No DEP or DBP intake estimates exceeded their respective RfDs. The DBP TDI (10??g/kg/day) was exceeded in three rubber industries and in phthalate manufacturing. These intake estimates are subject to several uncertainties; however, an occupational contribution to phthalate daily intake is clearly indicated in some industries. PMID:20010977

  1. Hypoxia markers are expressed in interneurons exposed to recurrent seizures.

    PubMed

    Gualtieri, Fabio; Marinelli, Carla; Longo, Daniela; Pugnaghi, Matteo; Nichelli, Paolo F; Meletti, Stefano; Biagini, Giuseppe

    2013-03-01

    An early but transient decrease in oxygen availability occurs during experimentally induced seizures. Using pimonidazole, which probes hypoxic insults, we found that by increasing the duration of pilocarpine-induced status epilepticus (SE) from 30 to 120 min, counts of pimonidazole-immunoreactive neurons also increased (P < 0.01, 120 vs 60 and 30 min). All the animals exposed to SE were immunopositive to pimonidazole, but a different scenario emerged during epileptogenesis when a decrease in pimonidazole-immunostained cells occurred from 7 to 14 days, so that only 1 out of 4 rats presented with pimonidazole-immunopositive cells. Pimonidazole-immunoreactive cells robustly reappeared at 21 days post-SE induction when all animals (7 out of 7) had developed spontaneous recurrent seizures. Specific neuronal markers revealed that immunopositivity to pimonidazole was present in cells identified by neuropeptide Y (NPY) or somatostatin antibodies. At variance, neurons immunopositive to parvalbumin or cholecystokinin were not immunopositive to pimonidazole. Pimonidazole-immunopositive neurons expressed remarkable immunoreactivity to hypoxia-inducible factor 1? (HIF-1?). Interestingly, surgical samples obtained from pharmacoresistant patients showed neurons co-labeled by HIF-1? and NPY antibodies. These interneurons, along with parvalbumin-positive interneurons that were negative to HIF-1?, showed immunopositivity to markers of cell damage, such as high-mobility group box 1 in the cytoplasm and cleaved caspase-3 in the nucleus. These findings suggest that interneurons are continuously endangered in rodent and human epileptogenic tissue. The presence of hypoxia and cell damage markers in NPY interneurons of rats and patients presenting with recurrent seizures indicates a mechanism of selective vulnerability in a specific neuronal subpopulation. PMID:23073716

  2. Respiratory epithelial cell lines exposed to anoxia produced inflammatory mediator.

    PubMed

    Shahriary, Cyrus M; Chin, Terry W; Nussbaum, Eliezer

    2012-12-01

    Human epithelial cell lines were utilized to examine the effects of anoxia on cellular growth and metabolism. Three normal human epithelial cells lines (A549, NHBE, and BEAS-2B) as well as a cystic fibrosis cell line (IB3-1) and its mutation corrected cell line (C38) were grown in the presence and absence of oxygen for varying periods of time. Interleukin-8 (IL-8) levels were measured by enzyme-linked immunosorbent assay technique. Cellular metabolism and proliferation were assayed by determining mitochondrial oxidative burst activity by tetrazolium compound reduction. The viability of cells was indirectly measured by lactate dehydrogenase release. A549, NHBE, and BEAS-2B cells cultured in the absence of oxygen showed a progressive decrease in metabolic activity and cell proliferation after one to three days. There was a concomitant increase in IL-8 production. Cell lines from cystic fibrosis (CF) patients did not show a similar detrimental effect of anoxia. However, the IL-8 level was significantly increased only in IB3-1 cells exposed to anoxia after two days. Anoxia appears to affect certain airway epithelial cell lines uniquely with decreased cellular proliferation and a concomitant increased production of a cytokine with neutrophilic chemotactic activity. The increased ability of the CF cell line to respond to anoxia with increased secretion of inflammatory cytokines may contribute to the inflammatory damage seen in CF bronchial airway. This study indicates the need to use different cell lines in in vitro studies investigating the role of epithelial cells in airway inflammation and the effects of environmental influences. PMID:23301190

  3. Toxicokinetics of captan and folpet biomarkers in orally exposed volunteers.

    PubMed

    Berthet, Aurélie; Bouchard, Michèle; Danuser, Brigitta

    2012-03-01

    The time courses of key biomarkers of exposure to captan and folpet was assessed in accessible biological matrices of orally exposed volunteers. Ten volunteers ingested 1? mg kg(-1) body weight of captan or folpet. Blood samples were withdrawn at fixed time periods over the 72 ?h following ingestion and complete urine voids were collected over 96 ?h post-dosing. The tetrahydrophthalimide (THPI) metabolite of captan along with the phthalimide (PI) and phthalic acid metabolites of folpet were then quantified in these samples. Plasma levels of THPI and PI increased progressively after ingestion, reaching peak values ~10 and 6 ?h post-dosing, respectively; subsequent elimination phase appeared monophasic with a mean elimination half-life (t(½) ) of 15.7 and 31.5? h, respectively. In urine, elimination rate time courses of PI and phthalic acid evolved in parallel, with respective t(½) of 27.3 and 27.6? h; relatively faster elimination was found for THPI, with mean t(½) of 11.7? h. However, phthalic acid was present in urine in 1000-fold higher amounts than PI. In the 96 ?h period post-treatment, on average 25% of folpet dose was excreted in urine as phthalic acid as compared with only 0.02% as PI. The corresponding value for THPI was 3.5%. Overall, THPI and PI appear as interesting biomarkers of recent exposure, with relatively short half-lives; their sensitivity to assess exposure in field studies should be further verified. Although not a metabolite specific to folpet, the concomitant use of phthalic acid as a major biomarker of exposure to folpet should also be considered. PMID:21381057

  4. Ultrasonic emissions from conifer xylem exposed to repeated freezing.

    PubMed

    Mayr, Stefan; Zublasing, Verena

    2010-01-01

    Ultrasonic emission measurements enable the analysis of xylem cavitation induced by drought and freeze-thaw events. Several studies have indicated that ultrasonic acoustic emissions (UAE) in conifers occur upon freezing and not upon thawing, although classical theory has postulated gas bubble formation during freezing and cavitation during thawing. We analyzed the pattern and quality of freeze-thaw-induced UAE in seven conifers (Abies alba, Larix decidua, Juniperus communis, Picea abies, Pinus cembra, Pinus mugo, Pinus sylvestris). Axes samples dehydrated to different water potentials were exposed to repeated frost cycles. The number, amplitude and energy of UAE signals were registered and related to water potential, temperature course and wood characteristics (wood density, tracheid diameter). For P. abies, ultrasonic emission analysis was also performed on bark samples, xylem samples without bark, as well as on stems of young potted trees. In all conifers, UAE were registered in water-stressed samples but not in saturated or dehydrated samples. No signals were emitted by the bark of P. abies. Ultrasonic activity occurred only upon freezing, and identical patterns were observed in axes samples and stems of potted P. abies trees. A weak positive relationship between tracheid diameter and UAE energy was observed, indicating wide tracheids to emit signals with higher energy. The classical bubble formation hypothesis cannot sufficiently explain the occurrence of UAE during freezing and upon repeated temperature cycles, as demonstrated in this study. We suggest that the low water potential of ice induces air-seeding near the ice-water interface, and consequently, causes UAE. PMID:19692146

  5. Fluctuations of an Exposed ?-Helix Involved in Lipoxygenase Substrate Recognition

    PubMed Central

    2014-01-01

    The second helix in lipoxygenases adapts to permit substrate access to the active site, but details of this process are varied and poorly understood. We therefore examined the dynamics of helix 2 in solutions of spin-labeled soybean lipoxygenase-1 and spin relaxation at 60 K of the spin-labels by catalytic iron. Helix 2 in soybean lipoxygenase structures is surface-exposed and contains one turn of ?-helix, centrally located. A site-directed spin-label scan of 18 of the 21 helix 2 residues, and electron paramagnetic resonance, showed that the ?-helical segment became unusually mobile, on a nanosecond time scale, under conditions favoring substrate binding (pH 9 and lipid addition), while segments before and after had relatively unchanged dynamics. Backbone dynamics of residues in the ?-helical segment appeared to be correlated, at pH 9. Samples also were frozen to examine the polarity and proticity of the local environments, the effect of the local environment on intrinsic relaxation, and dipolar relaxation by two symmetries of catalytic iron. The average hyperfine tensor component, Azz, of four ?-helix residues decreased by 1.75 G, with an increase in pH from 7 to 9, while it remained unaffected for nearby buried residues. Power saturation data suggested the change in polarity specific to the ?-helix altered the intrinsic relaxation rates. Different symmetries of iron contributed to distance-dependent magnetic relaxation. We interpret these data to mean that a ?-helix in the second helix of plant lipoxygenases is highly dynamic and is the site where lipid chains penetrate to inner helices that outline the substrate pocket. PMID:25036469

  6. Assessment of neuro behavioral disorders in workers exposed to organic solvents in a publication house

    PubMed Central

    Labbafinejad, Yasser; Mohammadi, Saber; Mirzamohammadi, Elham; Ghaffari, Mostafa; Attarchi, Mirsaeed; Amiri, Azadeh

    2014-01-01

    Background: Organic solvents are known as a group of organic compounds, widely used in industry and to which many workers are exposed. Neurotoxicity is one of the most important complications of the chronic exposure to the solvents and may causes neurobehavioral disorders in workers. We have studied the frequency of neurobehavioral disorders in workers exposed to organic solvents in one of the publishing houses in Tehran. Methods: In this cross-sectional study, 510 workers of a publishing house, having been employed at least a year before the research, were selected to be studied. Among them, 345 workers had been exposed to organic solvents and the other (165 workers) had not. Data were collected using a questionnaire. This questionnaire included demographic and occupational information, and the Swedish Q16 questionnaire. Variables included age, duration of employment, working shift, and smoking. Then we compared both groups in terms of neurobehavioral disorders, using statistical methods. Results: The mean score of the Swedish Q16 questionnaire in the exposed group (4.8±4.4) was significantly higher than the non-exposed group (3.2±3.1) (p=0.001). According to the questionnaire score, the frequency of neurobehavioral disorders in the exposed group was 38% and in the non-exposed group was 22% (p=0.001). We estimated that the frequency of neurobehavioral disorders in the exposed group was significantly higher than the non-exposed group (p<0.05) using regression analysis and removal of the confounding factors. Conclusion: This study shows that the frequency of the neurobehavioral disorders in the exposed group is significantly higher than the non-exposed group. PMID:25250248

  7. The affect of the space environment on the survival of Halorubrum chaoviator and Synechococcus (Nägeli): data from the Space Experiment OSMO on EXPOSE-R

    NASA Astrophysics Data System (ADS)

    Mancinelli, R. L.

    2015-01-01

    We have shown using ESA's Biopan facility flown in Earth orbit that when exposed to the space environment for 2 weeks the survival rate of Synechococcus (Nägeli), a halophilic cyanobacterium isolated from the evaporitic gypsum-halite crusts that form along the marine intertidal, and Halorubrum chaoviator a member of the Halobacteriaceae isolated from an evaporitic NaCl crystal obtained from a salt evaporation pond, were higher than all other test organisms except Bacillus spores. These results led to the EXPOSE-R mission to extend and refine these experiments as part of the experimental package for the external platform space exposure facility on the ISS. The experiment was flown in February 2009 and the organisms were exposed to low-Earth orbit for nearly 2 years. Samples were either exposed to solar ultraviolet (UV)-radiation (? > 110 nm or ? > 200 nm, cosmic radiation (dosage range 225-320 mGy), or kept in darkness shielded from solar UV-radiation. Half of each of the UV-radiation exposed samples and dark samples were exposed to space vacuum and half kept at 105 pascals in argon. Duplicate samples were kept in the laboratory to serve as unexposed controls. Ground simulation control experiments were also performed. After retrieval, organism viability was tested using Molecular Probes Live-Dead Bac-Lite stain and by their reproduction capability. Samples kept in the dark, but exposed to space vacuum had a 90 +/- 5% survival rate compared to the ground controls. Samples exposed to full UV-radiation for over a year were bleached and although results from Molecular Probes Live-Dead stain suggested ~10% survival, the data indicate that no survival was detected using cell growth and division using the most probable number method. Those samples exposed to attenuated UV-radiation exhibited limited survival. Results from of this study are relevant to understanding adaptation and evolution of life, the future of life beyond earth, the potential for interplanetary transfer of viable microbes via meteorites and dust particles as well as spacecraft, and the physiology of halophiles.

  8. Biomarker responses in river otters experimentally exposed to oil contamination.

    PubMed

    Ben-David, M; Duffy, L K; Bowyer, R T

    2001-07-01

    Investigations in Prince William Sound (Alaska, USA) following the Exxon Valdez oil spill (EVOS) revealed that river otters (Lontra canadensis) on oiled shores had lower body mass and elevated values of biomarkers, than did otters living on nonoiled shores. In addition, otters from oiled areas selected different habitats, had larger home ranges, and less diverse diets than animals living in nonoiled areas. These differences between river otters from oiled shores and those from nonoiled areas strongly suggested that oil contamination had an effect on physiological and behavioral responses of otters. In this study, we explored the effects of crude oil contamination on river otters experimentally. We hypothesized that exposure to oil would result in elevated values of biomarkers, indicating induced physiological stress. Fifteen wild-caught male river otters were exposed to two levels of weathered crude oil (i.e., control, 5 ppm/day/kg body mass, and 50 ppm/day/kg body mass) under controlled conditions in captivity at the Alaska Sealife Center in Seward (Alaska, USA). Responses of captive river otters to oil ingestion provided mixed results in relation to our hypotheses. Although hemoglobin (Hb, and associated red blood cells) and white blood cells, and possibly interleukin-6 immunoreactive responded in the expected manner, other parameters did not. Aspartate aminotransferase, alanine aminotransferase, and haptoglobin (Hp), did not increase in response to oiling or decreased during rehabilitation. Conversely, principle-component analysis identified values of alkaline phosphatase as responding to oil ingestion in river otters. Our results suggested that opposing processes were concurring in the oiled otters. Elevated production of Hp in response to tissue damage by hydrocarbons likely occurred at the same time with increased removal of Hp-Hb complex from the serum, producing an undetermined pattern in the secretion of Hp. Thus, the use of individual biomarkers as indicators of exposure to pollutants may lead to erroneous conclusions because interactions in vivo can be complicated and act in opposite directions. Additionally, the biomarkers used in investigating effects of oiling on live animals usually are related to the heme molecule. Because of the opposing processes that may occur within an animal, data from a suite of heme-related biomarkers may produce results that are difficult to interpret. Therefore, we advocate the exploration and development of other biomarkers that will be independent from the heme cycle and provide additional information to the effect of oiling on live mammals. PMID:11504223

  9. Ventilatory responses in awake guinea pigs exposed to acid aerosols.

    PubMed

    Roth, S H; Bjarnason, S G; De Sanctis, G T; Feroah, T; Jiang, X; Karkhanis, A; Green, F H

    1998-06-26

    This study reports experiments designed to evaluate the dose and temporal effects of an atmospheric pollutant, sulfuric acid (H2SO4) aerosol, on the dynamic components of the respiratory cycle. Ventilation was measured in a whole-body barometric plethysmograph in unanesthetized, unrestrained animals following a 4-h exposure to H2SO4 aerosol at 14.1, 20.1, or 43.3 mg/m3. Lung injury was assessed by histopathology and bronchoalveolar lavage (BAL). Aerosol exposure with H2SO4 caused marked alterations in both the magnitude and composition of the ventilatory response, which were both dose and time dependent. At the highest concentration tested, there was a significant increase in tidal volume (deltaVt) and a decrease in breathing frequency (f) immediately after exposure. Analysis of BAL fluid at this time showed increased inflammatory cells and protein in the acid exposed animals, and histology showed hyaline membranes and acute inflammatory cells in the proximal acinar region. By 24 h postexposure, f significantly increased whereas deltaVt decreased. This pattern of breathing was interspersed with short periods of apnea. The onset of rapid, shallow breathing was associated with histological evidence of diffuse pulmonary edema. By contrast, the immediate postexposure period at the lowest concentration of H2SO4 aerosol was characterized by a significant increase in f and little or no effect on deltaVt. These effects diminished with time, and at 24 h postexposure ventilatory parameters were indistinguishable from baseline values. An apparent crossover between the effects associated with the high and low exposure concentrations was seen at the intermediate exposure concentration; however, closer inspection of these findings on an animal-by-animal basis revealed two populations of animals with respiratory characteristics of either the high-exposure or low-exposure groups. The data suggest that the guinea pig exhibits complex interactions between dose and time to response that are consistent with the activation of neural reflexes. The indirect plethysmographic method provides a simple means to assess these responses in a model system that avoids the use of anesthetics, surgery, and restraint. PMID:9638899

  10. Toxicological outcomes in rats exposed to inhaled ethanol during gestation.

    PubMed

    Beasley, Tracey E; Evansky, Paul A; Martin, Sheppard A; McDaniel, Katherine L; Moser, Virginia C; Luebke, Robert W; Norwood, Joel; Rogers, John M; Copeland, Carey B; Bushnell, Philip J

    2014-01-01

    Recent legislation has encouraged replacing petroleum-based fuels with renewable alternatives including ethanol, which is typically blended with gasoline in the United States at concentrations up to 10%, with allowances for concentrations up to 85% for some vehicles. Efforts to increase the amount of ethanol in gasoline have prompted concerns about the potential toxicity of inhaled ethanol vapors from these fuels. The well-known sensitivity of the developing nervous and immune systems to ingested ethanol, and the lack of information about its toxicity by inhalation prompted the present work on its potential developmental effects in a rat model. Pregnant Long-Evans rats were exposed for 6.5h/day on days 9-20 of gestation to clean air or ethanol vapor at concentrations of 5000, 10,000, or 21,000 ppm, which resulted in estimated peak blood ethanol concentrations (BECs) of 2.3, 6.7, and 192 mg/dL, respectively. No overt toxicity in the dams was observed. Ethanol did not affect litter size or weight, or postnatal weight gain in the pups. Motor activity was normal in offspring through postnatal day (PND) 29. On PND 62, the 5000 and 21,000 ppm groups were more active than controls. On PND 29 and 62, offspring were tested with a functional observational battery, which revealed small changes in the neuromuscular and sensorimotor domains that were not systematically related to dose. Cell-mediated and humoral immunity were not affected by ethanol exposure in 6-week-old offspring. Systolic blood pressure was increased by 10,000 ppm ethanol in males at PND 90 but not at PND 180. No differences in lipoprotein profile, liver function, or kidney function were observed. In summary, prenatal exposure to inhaled ethanol caused some mild changes in physiological and behavioral development in offspring that were not clearly related to inhaled concentration or BEC, and did not produce detectable changes in immune function. This low toxicity of inhaled ethanol may result from the slow rise in BEC by the inhalation route. PMID:25092052

  11. Integrity of Disposable Nitrile Exam Gloves Exposed to Simulated Movement

    PubMed Central

    Phalen, Robert N.; Wong, Weng Kee

    2011-01-01

    Every year, millions of health care, first responder, and industry workers are exposed to chemical and biological hazards. Disposable nitrile gloves are a common choice as both a chemical and physical barrier to these hazards, especially as an alternative to natural latex gloves. However, glove selection is complicated by the availability of several types or formulations of nitrile gloves, such as low-modulus, medical-grade, low-filler, and cleanroom products. This study evaluated the influence of simulated movement on the physical integrity (i.e., holes) of different nitrile exam glove brands and types. Thirty glove products were evaluated out-of-box and after exposure to simulated whole-glove movement for 2 hr. In lieu of the traditional 1-L water-leak test, a modified water-leak test, standardized to detect a 0.15 ± 0.05 mm hole in different regions of the glove, was developed. A specialized air inflation method simulated bidirectional stretching and whole-glove movement. A worst-case scenario with maximum stretching was evaluated. On average, movement did not have a significant effect on glove integrity (chi-square; p=0.068). The average effect was less than 1% between no movement (1.5%) and movement (2.1%) exposures. However, there was significant variability in glove integrity between different glove types (p ? 0.05). Cleanroom gloves, on average, had the highest percentage of leaks, and 50% failed the water-leak test. Low-modulus and medical-grade gloves had the lowest percentages of leaks, and no products failed the water-leak test. Variability in polymer formulation was suspected to account for the observed discrepancies, as well as the inability of the traditional 1-L water-leak test to detect holes in finger/thumb regions. Unexpectedly, greater than 80% of the glove defects were observed in the finger and thumb regions. It is recommended that existing water-leak tests be re-evaluated and standardized to account for product variability. PMID:21476169

  12. What's exposed? Mapping elements at risk from space

    NASA Astrophysics Data System (ADS)

    Taubenböck, Hannes; Klotz, Martin; Geiß, Christian

    2014-05-01

    The world has suffered from severe natural disasters over the last decennium. The earthquake in Haiti in 2010 or the typhoon "Haiyan" hitting the Philippines in 2013 are among the most prominent examples in recent years. Especially in developing countries, knowledge on amount, location or type of the exposed elements or people is often not given. (Geo)-data are mostly inaccurate, generalized, not up-to-date or even not available at all. Thus, fast and effective disaster management is often delayed until necessary geo-data allow an assessment of effected people, buildings, infrastructure and their respective locations. In the last decade, Earth observation data and methods have developed a product portfolio from low resolution land cover datasets to high resolution spatially accurate building inventories to classify elements at risk or even assess indirectly population densities. This presentation will give an overview on the current available products and EO-based capabilities from global to local scale. On global to regional scale, remote sensing derived geo-products help to approximate the inventory of elements at risk in their spatial extent and abundance by mapping and modelling approaches of land cover or related spatial attributes such as night-time illumination or fractions of impervious surfaces. The capabilities and limitations for mapping physical exposure will be discussed in detail using the example of DLR's 'Global Urban Footprint' initiative. On local scale, the potential of remote sensing particularly lies in the generation of spatially and thematically accurate building inventories for the detailed analysis of the building stock's physical exposure. Even vulnerability-related indicators can be derived. Indicators such as building footprint, height, shape characteristics, roof materials, location, and construction age and structure type have already been combined with civil engineering approaches to assess building stability for large areas. Especially last generation optical sensors - often in combination with digital surface models - featuring very high geometric resolutions are perceived as advantageous for operational applications, especially for small to medium scale urban areas. With regard to user-oriented product generation in the FP-7project SENSUM, a multi-scale and multi-source reference database has been set up to systematically screen available products - global to local ones - with regard to data availability in data-rich and data-poor countries. Thus, the higher ranking goal in this presentation is to provide a systematic overview on EO-based data sets and their individual capabilities and limitations with respect to spatial, temporal and thematic details to support decision-making in before, during and after natural disasters.

  13. MMPI Profile Types of Exposers, Rapists, and Assaulters in a Court Services Population

    ERIC Educational Resources Information Center

    Rader, Charles M.

    1977-01-01

    In this study, Minnesota Multiphasic Personality Inventory (MMPI) profiles of exposer (n=36), rapist (n=47), and assaulter (n=46) groups were investigated and compared. The most disturbed group, the rapists, had MMPI K-corrected mean raw scale scores that were significantly greater than those of the exposer group on many scales. (Author)

  14. Proline Accumulates in Plants Exposed to uv Radiation and Protects Them against uv-Induced Peroxidation

    Microsoft Academic Search

    P. P. Saradhi; S. AliaArora; K. V. S. K. Prasad

    1995-01-01

    Proline accumulated in the shoots of seedlings of rice (Oryza sativa), mustard (Brassica juncea) and mung bean (Vigna radiata) exposed to UV radiations. The level of proline in the seedlings increased significantly with increase in UV exposure time. The production of malondialdehyde (an indice of lipid peroxidation) was also higher in the shoots of seedlings exposed to UV radiation, as

  15. Shoaling as an antiparasite defence in minnows (Pimephales promelas) exposed to trematode

    E-print Network

    Wisenden, Brian D.

    Shoaling as an antiparasite defence in minnows (Pimephales promelas) exposed to trematode cercariae benefits of shoaling in fathead minnows exposed to larvae (cercariae) of two of their most common species should favour the evolution of cercariae-avoidance behaviours. 3. We evaluated shoal dimensions in groups

  16. Chronic toxicity of the bromoxynil formulation Buctril ® to Daphnia magna exposed continuously and intermittently

    Microsoft Academic Search

    Kevin J. Buhl; Steven J. Hamilton; James C. Schmulbach

    1993-01-01

    Two chronic toxicity tests were conducted in which Daphnia magna were either continuously or intermittently exposed to bromoxynil octanoate (BO; as Buctril®) for 28 d. In the intermittent exposure test, daphnids were exposed to daily pulses of BO with 24-h mean concentrations equal to those in the continuous exposure test, and the peak concentrations were three times the 24-h mean

  17. Long-term effects of lead poisoning on bone mineralization in vultures exposed to ammunition sources

    E-print Network

    Donázar, José A.

    Long-term effects of lead poisoning on bone mineralization in vultures exposed to ammunition lead accumulation decreases the degree of bone mineralization in vultures exposed to ammunition sources Accepted 1 September 2008 Keywords: Bioaccumulation Bone mineralization Egyptian vulture FTIR Lead shot a b

  18. Speciation of arsenic in rice and vegetables from arsenic exposed areas in Bangladesh

    Microsoft Academic Search

    Mir Misbahuddin; Abul Kashem Liton; M. Abdur Rahman Khan; M. Siddiqur Rahman; Salamat Khandker

    Foodstuffs from arsenic-exposed areas in Bangladesh may contain high concentration of total arsenic but their speciations are not known. About 600 samples of raw rice and vegetables were collected from two arsenic-exposed Upazillas. Speciation of arsenic was done using column chromatography and hydride generator atomic absorption spectrometer. The mean concentrations of inorganic arsenic, monomethylarsonic acid (MMA) and dimethyl- arsinic acid

  19. Mercury toxicity in the Amazon: contrast sensitivity and color discrimination of subjects exposed to mercury

    Microsoft Academic Search

    A. R. Rodrigues; C. R. B. Souza; A. M. Braga; P. S. S. Rodrigues; A. T. Silveira; E. T. B. Damin; M. I. T. Côrtes; A. J. O. Castro; G. A. Mello; J. L. F. Vieira; M. C. N. Pinheiro; D. F. Ventura; L. C. L. Silveira

    2007-01-01

    We measured visual performance in achromatic and chromatic spatial tasks of mercury-exposed subjects and compared the results with norms obtained from healthy individuals of similar age. Data were obtained for a group of 28 mercury-exposed subjects, comprising 20 Amazonian gold miners, 2 inhabitants of Amazonian riverside com- munities, and 6 laboratory technicians, who asked for medical care. Statistical norms were

  20. Trace element accumulation by moss and lichen exposed in bags in the city of Naples (Italy)

    Microsoft Academic Search

    P Adamo; S Giordano; S Vingiani; R Castaldo Cobianchi; P Violante

    2003-01-01

    This paper presents the results of a bioaccumulation study of trace elements in the Naples urban area based on the use of the moss Sphagnum capillifolium (Ehrh.) Hedw. and the lichen Pseudevernia furfuracea (L.) Zopf exposed in bags in 23 sites. Moss and lichen bags were exposed for 4 months starting from the beginning of July 1999. Bags gathering was

  1. COMPARISON OF EXPERIMENTAL DESIGNS USED TO DETECT CHANGES IN YIELDS OF CROPS EXPOSED TO ACIDIC PRECIPITATION

    EPA Science Inventory

    A comparison of experimental designs used to detect changes in yield of crops exposed to simulated acidic rain was performed. Seed yields were determined from field-grown soybeans(Glycine max) exposed to simulated rainfalls in which all ambient rainfalls were excluded by automati...

  2. Modeling lung cancer risks in laboratory dogs exposed to inhaled plutonium

    SciTech Connect

    Gilbert, E.S.; Park, J.F.; Buschbom, R.L.

    1990-06-01

    These analyses are based on data from a lifespan study of beagle dogs exposed to inhaled plutonium being conducted at Pacific Northwest Laboratory. An important goal of this study is to increase understanding of health risk resulting from this exposure, with particular attention to lung cancer risks. Data on humans exposed to plutonium are inadequate for achieving this goal.

  3. 76 FR 67761 - Establishment of the Attorney General's National Task Force on Children Exposed to Violence

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ...National Task Force on Children Exposed to Violence AGENCY: Office of Juvenile Justice and...National Task Force on Children Exposed to Violence (the Task Force) is established in...national problem of children's exposure to violence. The Task Force will conduct 4...

  4. Water balance in rats exposed to chronic centrifugation RUDY M. ORTIZ AND CHARLES E. WADE

    E-print Network

    Ortiz, Rudy M.

    Water balance in rats exposed to chronic centrifugation RUDY M. ORTIZ AND CHARLES E. WADE Life; accepted in final form 22 February 2000 Ortiz, Rudy M., and Charles E. Wade. Water balance in rats exposed to alter renal function, which could potentially affect water balance. Therefore, the present study

  5. Bioaccumulation of inorganic Hg by the juvenile cuttlefish Sepia officinalis1 exposed to 203

    E-print Network

    Paris-Sud XI, Université de

    1 Bioaccumulation of inorganic Hg by the juvenile cuttlefish Sepia officinalis1 exposed to 203 Hg the juvenile common cuttlefish Sepia officinalis following exposures via seawater and food28 using sensitive radiotracer technique (203 Hg). The cuttlefish readily concentrated 203 Hg when29 exposed via seawater

  6. Corrosion Resistance of Stainless Steels Exposed to Aggressive Environments With Particles And Water

    Microsoft Academic Search

    H. Tsaprailis; W. Kovacs; J. Tuggle; L. F. Garfias-Mesias

    2009-01-01

    The present work describes the corrosion studies (using electrochemical techniques) of coated and uncoated steels exposed to corrosive mixtures (including 6% ferric Chloride, alcohols, particles and water). Open Circuit Potential (OCP), Cyclic Potentiodynamic Polarization (CPP) and a modified version of the Zero Resistance Amperometry (ZRA) testing methodology were proposed to compare the corrosion resistance of several steel exposed to these

  7. Degradation of creep properties in a long-term thermally exposed nickel base superalloy

    Microsoft Academic Search

    J. Zrnik; P. Strunz; V. Vrchovinsky; O. Muransky; Z. Novy; A. Wiedenmann

    2004-01-01

    When exposed for long time at elevated temperatures of 430 and 650°C the nickel base superalloy EI 698 VD can experience a significant decrease in creep resistance. The cause of the creep degradation of nickel base superalloy is generally attributed to the microstructural instability at prolonged high temperature exposure. In this article, the creep-life data, generated on long thermally exposed

  8. THE CONTRIBUTION OF MODERN MEDICAL IMAGING TECHNOLOGY TO RADIATION HEALTH EFFECTS IN EXPOSED POPULATIONS

    E-print Network

    Fabrikant, J.I.

    2010-01-01

    health hazards to human populations exposed to low-level radiation.health hazards, particularly from ionizing and nonionizing radiation exposure of humanradiation, and to the task of determining risk estimates for establishing standards for protecting the health of exposed human

  9. Alteration in enzyme activities in liver and kidney of Channa punctatus exposed to endrin

    Microsoft Academic Search

    S. K. Sharma; K. V. Sastry

    1979-01-01

    ELLER (1971) studied the histopathological changes in the liver, gill, brain, pancreas and gonads of Salmo clarki. Hyperplasia of the islets of Langerhans was observed when chronically exposed to endrin by bath or in food. EISLER and EDMUNDS (1966) observed that northern puffers (Sphaeroides maculatus) exposed acutely to sublethal concentrations of endrin and impaired liver function as evidenced by the

  10. Susceptibility of eggs and adult fecundity of the lesser grain borer, Rhyzopertha dominica, exposed to methoprene

    Microsoft Academic Search

    Y. Chanbang; F. H. Arthur; G. E. Wilde; J. E. Throne; Bh. Subramanyam

    2008-01-01

    A series of tests were conducted to determine the susceptibility of eggs and neonates of the lesser grain borer Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae = Bostrychidae), exposed to the insect growth regulator, methoprene, on filter paper and on rough rice. In the first test, the hatch rate of eggs exposed on filter paper treated with methoprene at the label rate

  11. Differential Global Gene Expression Response Patterns of Human Endothelium Exposed to Shear Stress and Intraluminal Pressure

    Microsoft Academic Search

    Maria Andersson; Lena Karlsson; Per-Arne Svensson; Erik Ulfhammer; Mikael Ekman; Margareta Jernås; Lena M. S. Carlsson; Sverker Jern

    2005-01-01

    We investigated the global gene expression response of endothelium exposed to shear stress and intraluminal pressure and tested the hypothesis that the two biomechanical forces induce a differential gene expression response pattern. Intact living human conduit vessels (umbilical veins) were exposed to normal or high intraluminal pressure, or to low or high shear stress in combination with a physiological level

  12. Vapor Convection in Gypsum Plasterboard Exposed to Fire: Numerical Simulation and Validation

    Microsoft Academic Search

    S. V. Shepel; K. Ghazi Wakili; E. Hugi

    2010-01-01

    This article investigates the contribution of water vapor convection to heat transfer through gypsum plasterboard exposed to fire. The vapor is generated as a product of the endothermic dehydration reaction in gypsum, and it is then expelled from the material through the pore network by its own pressure, thereby taking part in the heat transfer from the fire-exposed to the

  13. Fish Embryos Exposed to Oil From BP Spill Develop Deformities, a Study Finds

    E-print Network

    Grosell, Martin

    Fish Embryos Exposed to Oil From BP Spill Develop Deformities, a Study Finds By MICHAEL WINESMARCH no evidence that the oil spill had reduced fish populations. "The oil concentrations used in these lab 24, 2014 Embryos of tuna and amberjack that were exposed to crude oil collected from the Deepwater

  14. Neurocognitive Screening of Lead-Exposed Andean Adolescents and Young Adults

    Microsoft Academic Search

    S. Allen Counter; Leo H. Buchanan; Fernando Ortega

    2009-01-01

    This study was designed to assess the utility of two psychometric tests with putative minimal cultural bias for use in field screening of lead (Pb)-exposed Ecuadorian Andean workers. Specifically, the study evaluated the effectiveness in Pb-exposed adolescents and young adults of a nonverbal reasoning test standardized for younger children, and compared the findings with performance on a test of auditory

  15. Lung cancer risks among lead smelter workers also exposed to arsenic

    Microsoft Academic Search

    Vagn Englyst; Nils-Göran Lundström; Lars Gerhardsson; Lars Rylander; Gunnar Nordberg

    2001-01-01

    Recent publications indicate an increased incidence of lung cancer in non-ferrous smelter workers exposed to lead. The present study provides further data on selected subgroups in one such cohort. The cohort was based on 3979 smelter workers employed for at least 1 year between 1928 and 1979, and also exposed to lead and included in the Blood Lead Register that

  16. Membrane stability of winter wheat plants exposed to subzero temperatures for variable lengths of time

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability to survive episodes of subfreezing temperature is essential to winter wheat. Fully cold-acclimated plants of six lines of winter wheat were exposed to -12, -14, -16 or -18° C, four 1-5 hours. Electrolyte leakage and plant survival were used to assess damage to the plants. Plants exposed ...

  17. Probabilistic evaluation of the sustainability of maintenance strategies for RC structures exposed to chloride ingress

    E-print Network

    Boyer, Edmond

    strategies used in reinforced concrete structures exposed to chlorides. The proposed approach is illustrated exposed to chloride ingress Emilio Bastidas-Arteaga1 , Franck Schoefs1 , Alaa Chateauneuf 2 , Mauricio-foodstuffs terminal wharf). The repair strategy consists of demolition of the polluted concrete and rebuilding

  18. IRON-CONTAINING COATINGS ON ASBESTOS-CEMENT PIPES EXPOSED TO AGGRESSIVE WATER

    EPA Science Inventory

    Coatings containing iron were found on asbestos-cement pipes exposed to a range of water qualities from very aggressive to nonaggressive. Under aggressive water conditions iron coatings had a granular, porous structure that prevented asbestos fibers from being exposed on the surf...

  19. SYSTEMS FOR EXPOSING MICE TO 2,450-MHZ ELECTROMAGNETIC FIELDS

    EPA Science Inventory

    Two systems for exposing mice to 2,450-MHz electromagnetic fields are described. In a waveguide system, four mice were placed in a Styrofoam cage and exposed dorsally to circularly polarized electromagnetic fields. The temperature and humidity in the mouse holder were kept consta...

  20. Bone lead content assessed by L-line x-ray fluorescence in lead-exposed and non-lead-exposed suburban populations in the United States.

    PubMed Central

    Rosen, J F; Crocetti, A F; Balbi, K; Balbi, J; Bailey, C; Clemente, I; Redkey, N; Grainger, S

    1993-01-01

    Measurements of lead (Pb) in bone reflect cumulative Pb exposure, whereas blood Pb levels are indices of absorption during the previous 21-30 days. This study was undertaken to estimate bone Pb concentrations by L-line x-ray fluorescence (LXRF) in a United States suburban population which was exposed to unusually high levels of Pb in emissions from an adjacent factory during 1963-1981, compared with concentrations similarly estimated in a matched suburban community without unusual Pb exposure. The mean bone Pb value in 269 residents of the highly exposed suburb (15 ppm) was 3-fold greater than that of the reference suburb (5 ppm). LXRF estimates of bone Pb identified those individuals at risk for adverse effects of Pb, whereas blood Pb levels were uninformative. Average LXRF-estimated bone Pb concentrations in residents of the unusually exposed suburb approximated estimated values in workers at Pb-processing factories. Images Fig. 1 PMID:8464891