Decreased detoxification genes and genome size make the human body louse an efficient model to study xenobiotic metabolism

PubMed Central

Lee, Si Hyeock; Kang, Jae Soon; Min, Jee Sun; Yoon, Kyong Sup; Strycharz, Joseph P.; Johnson, Reed; Mittapalli, Omprakash; Margam, Venu M.; Sun, Weilin; Li, Hong-Mei; Xie, Jun; Wu, Jing; Kirkness, Ewen F.; Berenbaum, May R.; Pittendrigh, Barry R.; Clark, J. Marshall

2010-01-01

The human body louse, Pediculus humanus humanus, has one of the smallest insect genomes, containing ~10,775 annotated genes (Kirkness et al. 2010). Annotation of detoxification [cytochrome P450 monooxygenase (P450), glutathione-S-transferase (GST), esterase (Est), and ATP-binding cassette transporter (ABC transporter)] genes revealed that they are dramatically reduced in P. h. humanus compared to other insects except for Apis mellifera. There are 37 P450, 13 GST and 17 Est genes present in P. h. humanus, approximately half of that found in Drosophila melanogaster and Anopheles gambiae. The number of putatively functional ABC transporter genes in P. h. humanus and A. mellifera are the same (36) but both have fewer than An. gambiae (44) or D. melanogaster (65). The reduction of detoxification genes in P. h. humanus may be due to their simple life history, where they do not encounter a wide variety of xenobiotics. Neuronal component genes are highly conserved across different insect species as expected due to their critical function. Although reduced in number, P. h. humanus still retains at least a minimum repertoire of genes known to confer metabolic or toxicokinetic resistance to xenobiotics (e.g., Cyp3 clade P450s, Delta GSTs, B clade Ests and B/C subfamily ABC transporters), suggestive of its high potential for resistance development. PMID:20561088

Comparison of the humoral and cellular immune responses between body and head lice following bacterial challenge.

PubMed

Kim, Ju Hyeon; Min, Jee Sun; Kang, Jae Soon; Kwon, Deok Ho; Yoon, Kyong Sup; Strycharz, Joseph; Koh, Young Ho; Pittendrigh, Barry Robert; Clark, J Marshall; Lee, Si Hyeock

2011-05-01

The differences in the immune response between body lice, Pediculus humanus humanus, and head lice, Pediculus humanus capitis, were investigated initially by measuring the proliferation rates of two model bacteria, a Gram-positive Staphylococcus aureus and a Gram-negative Escherichia coli, following challenge by injection. Body lice showed a significantly reduced immune response compared to head lice particularly to E. coli at the early stage of the immune challenge. Annotation of the body louse genome identified substantially fewer immune-related genes compared with other insects. Nevertheless, all required genetic components of the major immune pathways, except for the immune deficiency (Imd) pathway, are still retained in the body louse genome. Transcriptional profiling of representative genes involved in the humoral immune response, following bacterial challenge, revealed that both body and head lice, regardless of their developmental stages, exhibited an increased immune response to S. aureus but little to E. coli. Head lice, however, exhibited a significantly higher phagocytotic activity against E. coli than body lice, whereas the phagocytosis against S. aureus differed only slightly between body and head lice. These findings suggest that the greater immune response in head lice against E. coli is largely due to enhanced phagocytosis and not due to differences in the humoral immune response. The reduced phagocytotic activity in body lice could be responsible, in part, for their increased vector competence. Copyright © 2011 Elsevier Ltd. All rights reserved.

The prevalence of Pediculus humanus capitis and the coexistence of intestinal parasites in young children in boarding schools in Sivas, Turkey.

PubMed

Değerli, Serpil; Malatyali, Erdoğan; Çeliksöz, Ali; Özçelik, Semra; Mumcuoğlu, Kosta Y

2012-01-01

The aim of this study was to investigate the prevalence of Pediculus humanus capitis and the coexistence of intestinal parasites in boarding primary schools in Sivas, Turkey. Seven hundred seventy-two students (350 [45.3%] girls, 422 [54.7%] boys) were evaluated with combing for the presence of head lice, collection of fecal samples, and examination of the perianal region for intestinal parasites using the cellophane tape method. The overall infestation rate for head lice was 6% (n=46). Nine children had evidence of nits only (1.2%), whereas living lice and nits or eggs were found in 37 children (4.8%). Girls were significantly more commonly infested (12.9%) than boys (0.2%). Of the parameters evaluated, socioeconomic level, number of rooms per family, and size and weight of the children were statistically significantly different between the children with and without lice. Although the infestation rate of children with intestinal parasites was higher in the head louse-infested group (23.9%) than in the group of children without lice (17.6%), the differences were not statistically significant. © 2011 Wiley Periodicals, Inc.

Bioactivity of Argentinean Essential Oils Against Permethrin-Resistant Head Lice, Pediculus humanus capitis

PubMed Central

Toloza, Ariel C; Zygadlo, Julio; Biurrun, Fernando; Rotman, Alicia; Picollo, María I

2010-01-01

Infestation with the head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), is one of the most common parasitic infestation of humans worldwide. Traditionally, the main treatment for control of head lice is chemical control that is based in a wide variety of neurotoxic synthetic insecticides. The repeated overuse of these products has resulted in the selection of resistant populations of head lice. Thus, plant-derived insecticides, such as the essential oils seem to be good viable alternatives as some have low toxicity to mammals and are biodegradable. We determined the insecticidal activity of 25 essential oils belonging to several botanical families present in Argentina against permethrin-resistant head lice. Significant differences in fumigant activity against head lice were found among the essential oils from the native and exotic plant species. The most effective essential oils were Cinnamomum porphyrium, followed by Aloysia citriodora (chemotype 2) and Myrcianthes pseudomato, with KT50 values of 1.12, 3.02 and 4.09; respectively. The results indicate that these essential oils are effective and could be incorporated into pediculicide formulations to control head lice infestations once proper formulation and toxicological tests are performed. PMID:21062140

Bioactivity of Argentinean essential oils against permethrin-resistant head lice, Pediculus humanus capitis.

PubMed

Toloza, Ariel C; Zygadlo, Julio; Biurrun, Fernando; Rotman, Alicia; Picollo, María I

2010-01-01

Infestation with the head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), is one of the most common parasitic infestation of humans worldwide. Traditionally, the main treatment for control of head lice is chemical control that is based in a wide variety of neurotoxic synthetic insecticides. The repeated overuse of these products has resulted in the selection of resistant populations of head lice. Thus, plant-derived insecticides, such as the essential oils seem to be good viable alternatives as some have low toxicity to mammals and are biodegradable. We determined the insecticidal activity of 25 essential oils belonging to several botanical families present in Argentina against permethrin-resistant head lice. Significant differences in fumigant activity against head lice were found among the essential oils from the native and exotic plant species. The most effective essential oils were Cinnamomum porphyrium, followed by Aloysia citriodora (chemotype 2) and Myrcianthes pseudomato, with KT(50) values of 1.12, 3.02 and 4.09; respectively. The results indicate that these essential oils are effective and could be incorporated into pediculicide formulations to control head lice infestations once proper formulation and toxicological tests are performed.

The unusual reproductive system of head and body lice (Pediculus humanus)

PubMed Central

ANDREWES, S.; CLARK, J. M.; ROSS, L.

2017-01-01

Abstract Insect reproduction is extremely variable, but the implications of alternative genetic systems are often overlooked in studies on the evolution of insecticide resistance. Both ecotypes of Pediculus humanus (Phthiraptera: Pediculidae), the human head and body lice, are human ectoparasites, the control of which is challenged by the recent spread of resistance alleles. The present study conclusively establishes for the first time that both head and body lice reproduce through paternal genome elimination (PGE), an unusual genetic system in which males transmit only their maternally derived chromosomes. Here, we investigate inheritance patterns of parental genomes using a genotyping approach across families of both ecotypes and show that heterozygous males exclusively or preferentially pass on one allele only, whereas females transmit both in a Mendelian fashion. We do however observe occasional transmission of paternal chromosomes through males, representing the first known case of PGE in which whole‐genome meiotic drive is incomplete. Finally, we discuss the potential implications of this finding for the evolution of resistance and invite the development of new theoretical models of how this knowledge might contribute to increasing the success of pediculicide‐based management schemes. PMID:29266297

Decreased detoxification genes and genome size make the human body louse an efficient model to study xenobiotic metabolism.

PubMed

Lee, S H; Kang, J S; Min, J S; Yoon, K S; Strycharz, J P; Johnson, R; Mittapalli, O; Margam, V M; Sun, W; Li, H-M; Xie, J; Wu, J; Kirkness, E F; Berenbaum, M R; Pittendrigh, B R; Clark, J M

2010-10-01

The human body louse, Pediculus humanus humanus, has one of the smallest insect genomes, containing ∼10 775 annotated genes. Annotation of detoxification [cytochrome P450 monooxygenase (P450), glutathione-S-transferase (GST), esterase (Est) and ATP-binding cassette transporter (ABC transporter)] genes revealed that they are dramatically reduced in P. h. humanus compared to other insects except for Apis mellifera. There are 37 P450, 13 GST and 17 Est genes present in P. h. humanus, approximately half the number found in Drosophila melanogaster and Anopheles gambiae. The number of putatively functional ABC transporter genes in P. h. humanus and Ap. mellifera are the same (36) but both have fewer than An. gambiae (44) or Dr. melanogaster (65). The reduction of detoxification genes in P. h. humanus may be a result of this louse's simple life history, in which it does not encounter a wide variety of xenobiotics. Neuronal component genes are highly conserved across different insect species as expected because of their critical function. Although reduced in number, P. h. humanus still retains at least a minimum repertoire of genes known to confer metabolic or toxicokinetic resistance to xenobiotics (eg Cyp3 clade P450s, Delta GSTs, B clade Ests and B/C subfamily ABC transporters), suggestive of its high potential for resistance development. © 2010 The Authors. Insect Molecular Biology © 2010 The Royal Entomological Society.

A Genome-Wide Identification of Basic Helix-Loop-Helix Motifs in Pediculus humanus corporis (Phthiraptera: Pediculidae)

PubMed Central

Wang, Xu-Hua; Wang, Yong; Zhang, De-Bao; Liu, A-Ke; Yao, Qin; Chen, Ke-Ping

2014-01-01

Abstract Basic helix-loop-helix (bHLH) proteins comprise a large superfamily of transcription factors, which are involved in the regulation of various developmental processes. bHLH family members are widely distributed in various eukaryotes including yeast, fruit fly, zebrafish, mouse, and human. In this study, we identified 55 bHLH motifs encoded in genome sequence of the human body louse, Pediculus humanus corporis (Phthiraptera: Pediculidae). Phylogenetic analyses of the identified P. humanus corporis bHLH (PhcbHLH) motifs revealed that there are 23, 11, 9, 1, 10, and 1 member(s) in groups A, B, C, D, E, and F, respectively. Examination to GenBank annotations of the 55 PhcbHLH members indicated that 29 PhcbHLH proteins were annotated in consistence with our analytical result, 8 were annotated different with our analytical result, 12 were merely annotated as hypothetical protein, and the rest 6 were not deposited in GenBank. A comparison on insect bHLH gene composition revealed that human body louse possibly has more hairy and E(spl) genes than other insect species. Because hairy and E(spl) genes have been found to negatively regulate the differentiation of insect preneural cells, it is suggested that the existence of additional hairy and E(spl) genes in human body louse is probably the consequence of its long period adaptation to the relatively dark and stable environment. These data provide good references for further studies on regulatory functions of bHLH proteins in the growth and development of human body louse. PMID:25434030

Head lice infestations: A clinical update.

PubMed

Cummings, Carl; Finlay, Jane C; MacDonald, Noni E

2018-02-01

Head lice ( Pediculus humanus capitis ) infestations are not a primary health hazard or a vector for disease, but they are a societal problem with substantial costs. Diagnosis of head lice infestation requires the detection of a living louse. Although pyrethrins and permethrin remain first-line treatments in Canada, isopropyl myristate/ST-cyclomethicone solution and dimeticone can be considered as second-line therapies when there is evidence of treatment failure.

Lethal effects of treatment with a special dimeticone formula on head lice and house crickets (Orthoptera, Ensifera: Acheta domestica and Anoplura, phthiraptera: Pediculus humanus). Insights into physical mechanisms.

PubMed

Richling, Ira; Böckeler, Wolfgang

2008-01-01

The present study provides the first convincing explanation of the mode of action of the medical device NYDA, a special dimeticone (CAS 9006-65-9) formula containing 92% of two dimeticones with different viscosities specifically designed for the physical treatment of head lice infestations (pediculosis capitis) by suffocation. Both, lice (Pediculus humanus) and house crickets (Acheta domestica) treated with this anti-head lice product are knocked out to the status "of no major vital signs" within less than 1 min that in consequence is accompanied irreversibly with the death of the respective insects. Scanning electron microscopical investigations have revealed that the cuticle is coated by a thin closed layer of the dimeticone formula that also enters the stigmata. In vivo observations and dissections of Acheta domestica have shown that application of the medical device to the thoracic stigmata invariably leads to rapid death; this is strongly correlated with the influx of the special dimeticone formula into the head trachea, whereby the solution effectively blocks the oxygen supply of the central nervous system. Dissections after application of the stained product show that it also enters the finest tracheal branches. Analogous in vivo observations in Pediculus humanus have confirmed the correlation between the disappearance of major vital signs and the displacement of air by the dimeticone formula in the tracheal system of the head. For both insect species, statistical data are provided for the chronological sequence of the filling of the tracheal system in relation to the respective vitality conditions of the Insects. On average, the special dimeticone formula reaches the insect's head tracheae within 0.5 min in house crickets and in less than 1 min in lice with a complete filling of the entire head tracheal system of lice within 3.5 min. In addition, a timed sequence of images illustrates this process for lice. The experiments clearly reveal the exclusive and pure physical mode of action of the tested dimeticone formula.

Response of Pediculus humanus capitis (Phthiraptera: Pediculidae) to Volatiles of Whole and Individual Components of the Human Scalp.

PubMed

Galassi, F G; Fronza, G; Toloza, A C; Picollo, M I; González-Audino, P

2018-05-04

The head louse Pediculus humanus capitis (De Geer) (Phthiraptera: Pediculidae) is a cosmopolitan human ectoparasite causing pediculosis, one of the most common arthropod parasitic conditions of humans. The mechanisms and/or chemicals involved in host environment recognition by head lice are still unknown. In this study, we evaluated the response of head lice to volatiles that emanate from the human scalp. In addition, we identified the volatile components of the odor and evaluated the attractive or repellent activity of their pure main components. The volatiles were collected by means of Solid Phase microextraction and the extract obtained was chemically analyzed by gas chromatograph-mass spectrometer. Twenty-four volatile were identified in the human scalp odor, with the main compounds being the following: nonanal, sulcatone, geranylacetone, and palmitic acid. Head lice were highly attracted by the blend human scalp volatiles, as well as by the individual major components. A significant finding of our study was to demonstrate that nonanal activity depends on the mass of the compound as it is repellent at high concentrations and an attractant at low concentrations. The results of this study indicate that head lice may use chemical signals in addition to other mechanisms to remain on the host.

The unusual reproductive system of head and body lice (Pediculus humanus).

PubMed

DE LA Filia, A G; Andrewes, S; Clark, J M; Ross, L

2018-06-01

Insect reproduction is extremely variable, but the implications of alternative genetic systems are often overlooked in studies on the evolution of insecticide resistance. Both ecotypes of Pediculus humanus (Phthiraptera: Pediculidae), the human head and body lice, are human ectoparasites, the control of which is challenged by the recent spread of resistance alleles. The present study conclusively establishes for the first time that both head and body lice reproduce through paternal genome elimination (PGE), an unusual genetic system in which males transmit only their maternally derived chromosomes. Here, we investigate inheritance patterns of parental genomes using a genotyping approach across families of both ecotypes and show that heterozygous males exclusively or preferentially pass on one allele only, whereas females transmit both in a Mendelian fashion. We do however observe occasional transmission of paternal chromosomes through males, representing the first known case of PGE in which whole-genome meiotic drive is incomplete. Finally, we discuss the potential implications of this finding for the evolution of resistance and invite the development of new theoretical models of how this knowledge might contribute to increasing the success of pediculicide-based management schemes. © 2017 The Authors. Medical and Veterinary Entomology published by John Wiley & Sons Ltd on behalf of Royal Entomological Society.

A genome-wide identification of basic helix-loop-helix motifs in Pediculus humanus corporis (Phthiraptera: Pediculidae).

PubMed

Wang, Xu-Hua; Wang, Yong; Zhang, De-Bao; Liu, A-Ke; Yao, Qin; Chen, Ke-Ping

2014-01-01

Basic helix-loop-helix (bHLH) proteins comprise a large superfamily of transcription factors, which are involved in the regulation of various developmental processes. bHLH family members are widely distributed in various eukaryotes including yeast, fruit fly, zebrafish, mouse, and human. In this study, we identified 55 bHLH motifs encoded in genome sequence of the human body louse, Pediculus humanus corporis (Phthiraptera: Pediculidae). Phylogenetic analyses of the identified P. humanus corporis bHLH (PhcbHLH) motifs revealed that there are 23, 11, 9, 1, 10, and 1 member(s) in groups A, B, C, D, E, and F, respectively. Examination to GenBank annotations of the 55 PhcbHLH members indicated that 29 PhcbHLH proteins were annotated in consistence with our analytical result, 8 were annotated different with our analytical result, 12 were merely annotated as hypothetical protein, and the rest 6 were not deposited in GenBank. A comparison on insect bHLH gene composition revealed that human body louse possibly has more hairy and E(spl) genes than other insect species. Because hairy and E(spl) genes have been found to negatively regulate the differentiation of insect preneural cells, it is suggested that the existence of additional hairy and E(spl) genes in human body louse is probably the consequence of its long period adaptation to the relatively dark and stable environment. These data provide good references for further studies on regulatory functions of bHLH proteins in the growth and development of human body louse. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

Isolation, Expression Analysis, and Functional Characterization of the First Antidiuretic Hormone Receptor in Insects

DTIC Science & Technology

2010-06-01

fruitfly Drosophila melanogaster and the honey bee Apis mellifera . Prog Neurobiol 80:1–19. 28. Larkin MA, et al. (2007) Clustal W and Clustal X version...receptors predicted or annotated in the Acyrthosiphon pisum, Pediculus humanus corporis, andApis mellifera genomes. The CAPA-related peptides in insects...prolixus CAPA Receptor Gene. CAPA receptor protein sequences identified or predicted in D. melanogaster (AAS65092) (13, 14), A. mellifera (NP_001091702

White piedra and pediculosis capitis in the same patient.

PubMed

Marques, Silvio Alencar; Richini-Pereira, Virgínia Bodelão; Camargo, Rosângela Maria Pires de

2012-01-01

White piedra is a superficial mycosis caused by the genus Trichosporon. It is characterized by nodules on the hair shaft. Pediculosis capitis is caused by Pediculus humanus var. capitis of the suborder Anoplura. Whereas pediculosis is a common infestation, clinical reports of white piedra are rare. Molecular biology procedures identified T. inkin as the agent of white piedra in this case report. The authors present associations between the two diseases in the same patient in order to highlight their clinical differences.

The body louse as a vector of reemerging human diseases.

PubMed

Raoult, D; Roux, V

1999-10-01

The body louse, Pediculus humanus humanus, is a strict human parasite, living and multiplying in clothing. Louse infestation is associated with cold weather and a lack of hygiene. Three pathogenic bacteria are transmitted by the body louse. Borrelia recurrentis is a spirochete, the agent of relapsing fever, recently cultured on axenic medium. Historically, massive outbreaks have occurred in Eurasia and Africa, but currently the disease is found only in Ethiopia and neighboring countries. Bartonella quintana is now recognized as an agent of bacillary angiomatosis bacteremia, trench fever, endocarditis, and chronic lymphadenopathy among the homeless. Rickettsia prowazekii is the agent of epidemic typhus. The most recent outbreak (and the largest since World War II) was observed in Burundi. A small outbreak was also reported in Russia in 1997. Louse infestation appears to become more prevalent worldwide, associated with a decline in social and hygienic conditions provoked by civil unrest and economic instability.

[Lice and lice-borne diseases in humans].

PubMed

Houhamdi, L; Parola, P; Raoult, D

2005-01-01

Among the three lice which parasite the human being, the human body louse, Pediculus humanus humanus, is a vector of infectious diseases. It lives and multiplies in clothes and human infestation is associated with cold weather and a lack of hygiene. Three pathogenic bacteria are transmitted by the body louse: 1) Rickettsia prowazekii, the agent of epidemic typhus of which the most recent outbreak (and the largest since World War II) was observed during the civil war in Burundi; 2) Borrelia recurrentis, the agent of relapsing fever, historically responsible of massive outbreaks in Eurasia and Africa, which prevails currently in Ethiopia and neighboring countries; 3) Bartonella quintana, the agent of trench fever, bacillary angiomatosis, chronic bacteremia, endocarditis, and lymphadenopathy. Body louse infestation, associated with a decline in social and hygienic conditions provoked by civil unrest and economic instability, is reemergent worldwide. Recently, a forth human pathogen, Acinetobacter baumannii, has been associated to the body louse.

Effect of Environmental Conditions and Toxic Compounds on the Locomotor Activity of Pediculus humanus capitis (Phthiraptera: Pediculidae).

PubMed

Ortega-Insaurralde, I; Toloza, A C; Gonzalez-Audino, P; Mougabure-Cueto, G A; Alvarez-Costa, A; Roca-Acevedo, G; Picollo, M I

2015-09-01

In this work, we evaluated the effect of environmental variables such as temperature, humidity, and light on the locomotor activity of Pediculus humanus capitis. In addition, we used selected conditions of temperature, humidity, and light to study the effects of cypermethrin and N,N-diethyl-3-methylbenzamide (DEET) on the locomotor activity of head lice. Head lice increased their locomotor activity in an arena at 30°C compared with activity at 20°C. When we tested the influence of the humidity level, the locomotor activity of head lice showed no significant differences related to humidity level, both at 30°C and 20°C. Concerning light influence, we observed that the higher the intensity of light, the slower the movement of head lice. We also demonstrated that sublethal doses of toxics may alter locomotor activity in adults of head lice. Sublethal doses of cypermethrin induced hyperactivated responses in adult head lice. Sublethal doses of DEET evocated hypoactivated responses in head lice. The observation of stereotyped behavior in head lice elicited by toxic compounds proved that measuring locomotor activity in an experimental set-up where environmental conditions are controlled would be appropriate to evaluate compounds of biological importance, such as molecules involved in the host-parasite interaction and intraspecific relationships. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Electron Microscopic Alterations in Pediculus humanus capitis Exposed to Some Pediculicidal Plant Extracts

PubMed Central

Akkad, Dina M. H. El; El-Gebaly, Naglaa Saad M.; Yousof, Hebat-Allah Salah A.; Ismail, Mousa A. M.

2016-01-01

Head lice, Pediculus humanus capitis, infestation is an important public health problem in Egypt. Inadequate application of topical pediculicides and the increasing resistance to the commonly used pediculicides made the urgent need for the development of new agents able to induce irreversible changes in the exposed lice leading to their mortality. The aim of the present work is to evaluate pediculicidal efficacy of some natural products such as olive oil, tea tree oil, lemon juice, and ivermectin separately in comparison with tetramethrin-piperonyl butoxide (licid), as a standard pediculicide commonly used in Egypt. The effects of these products were evaluated by direct observation using dissecting and scanning electron microscopes (SEM). Results showed that after 1 hr exposure time in vitro, absolute (100%) mortalities were recorded after exposure to 1% ivermectin and fresh concentrate lemon juice. The mortalities were decreased to 96.7% after exposure to tea tree oil. Very low percentage of mortality (23.3%) was recorded after 1 hr of exposure to extra virgin olive oil. On the other hand, the reference pediculicide (licid) revealed only mortality rate of 93.3%. On the contrary, no mortalities were recorded in the control group exposed to distilled water. By SEM examination, control lice preserved outer smooth architecture, eyes, antenna, respiratory spiracles, sensory hairs, and legs with hook-like claws. In contrast, dead lice which had been exposed to pediculicidal products showed damage of outer smooth architecture, sensory hairs, respiratory spiracles and/or clinching claws according to pediculicidal products used. PMID:27658606

Identification and characterization of an esterase involved in malathion resistance in the head louse Pediculus humanus capitis.

PubMed

Kwon, Deok Ho; Kim, Ju Hyeon; Kim, Young Ho; Yoon, Kyong Sup; Clark, J Marshall; Lee, Si Hyeock

2014-06-01

Enhanced malathion carboxylesterase (MCE) activity was previously reported to be involved in malathion resistance in the head louse Pediculus humanus capitis (Gao et al., 2006 [8]). To identify MCE, the transcriptional profiles of all five esterases that had been annotated to be catalytically active were determined and compared between the malathion-resistant (BR-HL) and malathion-susceptible (KR-HL) strains of head lice. An esterase gene, designated HLCbE3, exhibited approximately 5.4-fold higher transcription levels, whereas remaining four esterases did not exhibit a significant increase in their transcription in BR-HL, indicating that HLCbE3 may be the putative MCE. Comparison of the entire cDNA sequences of HLCbE3 revealed no sequence differences between the BR-HL and KR-HL strains and suggested that no single nucleotide polymorphism is associated with enhanced MCE activity. Two copies of the HLCbE3 gene were observed in BR-HL, implying that the over-transcription of HLCbE3 is due to the combination of a gene duplication and up-regulated transcription. Knockdown of HLCbE3 expression by RNA interference in the BR-HL strain led to increases in malathion susceptibility, confirming the identity of HLCbE3 as a MCE responsible for malathion resistance in the head louse. Phylogenetic analysis suggested that HLCbE3 is a typical dietary esterase and belongs to a clade containing various MCEs involved in malathion resistance. Copyright © 2014 Elsevier Inc. All rights reserved.

Molecular Survey of Head and Body Lice, Pediculus humanus, in France.

PubMed

Candy, Kerdalidec; Amanzougaghene, Nadia; Izri, Arezki; Brun, Sophie; Durand, Rémy; Louni, Meriem; Raoult, Didier; Fenollar, Florence; Mediannikov, Oleg

2018-05-01

Human lice, Pediculus humanus, are obligate blood-sucking parasites. Phylogenetically, they belong to several mitochondrial clades exhibiting some geographic differences. Currently, the body louse is the only recognized disease vector, with the head louse being proposed as an additional vector. In this article, we study the genetic diversity of head and body lice collected from Bobigny, a town located close to Paris (France), and look for louse-borne pathogens. By amplifying and sequencing the cytb gene, we confirmed the presence of clades A and B in France. Besides, by amplifying and sequencing both cytb and cox1 gene, we reported, for the first time, the presence of clade E, which has thus far only been found in lice from West Africa. DNA from Bartonella quintana was detected in 16.7% of body lice from homeless individuals, but in none of the head lice collected from 47 families. Acinetobacter DNA was detected in 11.5% of head lice belonging to all three clades and 29.1% of body lice. Six species of Acinetobacter were identified, including two potential new ones. Acinetobacter baumannii was the most prevalent, followed by Candidatus Acinetobacter Bobigny-1, Acinetobacter calcoaceticus, Acinetobacter nosocomialis, Acinetobacter junii, and Candidatus Acinetobacter Bobigny-2. Body lice were found to be infected only with A. baumannii. These findings show for the first time, the presence of clade E head lice in France. This study is also the first to report the presence of DNAs of several species of Acinetobacter in human head lice in France.

In vitro efficacy of five essential oils against Pediculus humanus capitis.

PubMed

Candy, Kerdalidec; Nicolas, Patrick; Andriantsoanirina, Valérie; Izri, Arezki; Durand, Rémy

2018-02-01

Treatment of head lice has relied mainly on the use of topical insecticides. Today, conventional topical pediculicides have suffered considerable loss of activity worldwide. There is increasing interest in the use of natural products such as essential oils for head louse control, and many of them are now incorporated into various over-the-counter products presented as pediculicides, often without proper evaluation. The aim of the present study was to assess the in vitro efficacy of five essential oils against adults of Pediculus humanus capitis using a contact filter paper toxicity bioassay. The chemical composition of the essential oils from wild bergamot, clove, lavender, tea tree, and Yunnan verbena was analyzed by gas chromatography-mass spectrometry. All treatments and controls were replicated three times on separate occasions over a period of 11 months. In all, 1239 living lice were collected from the scalp of 51 subjects, aged from 1 to 69 years. Clove oil, diluted either in coco oil or sunflower oil, demonstrated the best adulticidal activity, reaching > 90% mortality within 2 h in lice submitted to a 30-min contact. Yunnan verbena oil diluted in coco oil showed also a significant efficacy. Other essential oils showed a lower efficacy. The oil's major component(s) differed according to the tested oils and appeared chemically diverse. In the case of clove oil, the eugenol appeared as the main component. This study confirmed the potential interest of some of the essential oils tested, but not all, as products to include possibly in a pediculicidal formulation.

[The Distribution of Pediculus humanus capitis Among Primary School Pupils of the Turkish Chamber of Commerce and Stock Exchange Organisation in Van].

PubMed

Karaaslan, Selver; Yılmaz, Hasan

2015-03-01

This study was performed in order to study the prevalence of Pediculus humanus capitis (P. h. capitis). The study was carried out on pupils between 5-15 years old in a school and kindergarden belonging to the Turkish Chamber of Commerce and Stock Exchange Organization in Van City between November-December 2007. The hair of 863 pupils (especially the neck and the back of head areas), 385 girls and 478 boys, were examined for eggs, nymphs and adults of P. h. capitis. A questionnaire was given to the pupils, which was collected the following day. Lice and their eggs/nits, which were removed from the head of children were transferred to a bottle containing 5% glycerin in 70% ethyl alcohol. Later they were sent to the Parasitology Laboratory of the Health Research and Training Hospital of Yüzüncü Yıl University. Eggs/nits were found in 164 (42.6%) of the girls and in 34 (7.1%) of the boys (overall 198 (22.9%) infested pupils). The prevalence of P. h. capitis was high, especially in girls. The infestation rates observed and the evaluation of the questionnaire showed that there is a statistically significant relationships between pediculosis capitis and sex, level of family income, education level of the mother, number of baths taken per weekly, number of family members living in the same home, room number per capita, and hair length (p<0.001). However, there was no significant relationship between pediculosis capitis and cleaning materials used to wash the head (p>0.05).

Safety, Efficacy, and Physicochemical Characterization of Tinospora crispa Ointment: A Community-Based Formulation against Pediculus humanus capitis

PubMed Central

Torre, Gerwin Louis Tapan Dela; Ponsaran, Kerstin Mariae Gonzales; de Guzman, Angelica Louise Dela Peña; Manalo, Richelle Ann Mallapre; Arollado, Erna Custodio

2017-01-01

The high prevalence of pediculosis capitis, commonly known as head lice (Pediculus humanus capitis) infestation, has led to the preparation of a community-based pediculicidal ointment, which is made of common household items and the extract of Tinospora crispa stem. The present study aimed to evaluate the safety, efficacy, and physicochemical characteristics of the T. crispa pediculicidal ointment. The physicochemical properties of the ointment were characterized, and safety was determined using acute dermal irritation test (OECD 404), while the efficacy was assessed using an in vitro pediculicidal assay. Furthermore, the chemical compounds present in T. crispa were identified using liquid-liquid extraction followed by ultra-performance liquid chromatography quadruple time-of-flight mass spectrometric (UPLC-qTOF/MS) analysis. The community-based ointment formulation was light yellow in color, homogeneous, smooth, with distinct aromatic odor and pH of 6.92±0.09. It has spreadability value of 15.04±0.98 g·cm/sec and has thixotropic behavior. It was also found to be non-irritant, with a primary irritation index value of 0.15. Moreover, it was comparable to the pediculicidal activity of the positive control Kwell®, a commercially available 1% permethrin shampoo (P>0.05), and was significantly different to the activity of the negative control ointment, a mixture of palm oil and candle wax (P<0.05). These findings suggested that the community-based T. crispa pediculicidal ointment is safe and effective, having acceptable physicochemical characteristics. Its activity can be attributed to the presence of compounds moupinamide and physalin I. PMID:28877572

An unusual autopsy case of lethal hypothermia exacerbated by body lice-induced severe anemia.

PubMed

Nara, Akina; Nagai, Hisashi; Yamaguchi, Rutsuko; Makino, Yohsuke; Chiba, Fumiko; Yoshida, Ken-ichi; Yajima, Daisuke; Iwase, Hirotaro

2016-05-01

Pediculus humanus humanus (known as body lice) are commonly found in the folds of clothes, and can cause skin disorders when they feed on human blood, resulting in an itching sensation. Body lice are known as vectors of infectious diseases, including typhus, recurrent fever, and trench fever. An infestation with blood-sucking body lice induces severe cutaneous pruritus, and this skin disorder is known as "vagabond's disease." A body lice infestation is sometimes complicated with iron deficiency anemia. In the present case, a man in his late 70s died of lethal hypothermia in the outdoors during the winter season. The case history and autopsy findings revealed that the cause of the lethal hypothermia was iron deficiency anemia, which was associated with a prolonged infestation of blood-sucking body lice. Also, he had vagabond's disease because the skin on his body was abnormal and highly pigmented. This is an unusual autopsy case since the body lice contributed to the cause of the death.

Genotyping of human lice suggests multiple emergencies of body lice from local head louse populations.

PubMed

Li, Wenjun; Ortiz, Gabriel; Fournier, Pierre-Edouard; Gimenez, Gregory; Reed, David L; Pittendrigh, Barry; Raoult, Didier

2010-03-23

Genetic analyses of human lice have shown that the current taxonomic classification of head lice (Pediculus humanus capitis) and body lice (Pediculus humanus humanus) does not reflect their phylogenetic organization. Three phylotypes of head lice A, B and C exist but body lice have been observed only in phylotype A. Head and body lice have different behaviours and only the latter have been involved in outbreaks of infectious diseases including epidemic typhus, trench fever and louse borne recurrent fever. Recent studies suggest that body lice arose several times from head louse populations. By introducing a new genotyping technique, sequencing variable intergenic spacers which were selected from louse genomic sequence, we were able to evaluate the genotypic distribution of 207 human lice. Sequence variation of two intergenic spacers, S2 and S5, discriminated the 207 lice into 148 genotypes and sequence variation of another two intergenic spacers, PM1 and PM2, discriminated 174 lice into 77 genotypes. Concatenation of the four intergenic spacers discriminated a panel of 97 lice into 96 genotypes. These intergenic spacer sequence types were relatively specific geographically, and enabled us to identify two clusters in France, one cluster in Central Africa (where a large body louse outbreak has been observed) and one cluster in Russia. Interestingly, head and body lice were not genetically differentiated. We propose a hypothesis for the emergence of body lice, and suggest that humans with both low hygiene and head louse infestations provide an opportunity for head louse variants, able to ingest a larger blood meal (a required characteristic of body lice), to colonize clothing. If this hypothesis is ultimately supported, it would help to explain why poor human hygiene often coincides with outbreaks of body lice. Additionally, if head lice act as a reservoir for body lice, and that any social degradation in human populations may allow the formation of new populations of body lice, then head louse populations are potentially a greater threat to humans than previously assumed.

The rhizome of Reclinomonas americana, Homo sapiens, Pediculus humanus and Saccharomyces cerevisiae mitochondria.

PubMed

Georgiades, Kalliopi; Raoult, Didier

2011-10-20

Mitochondria are thought to have evolved from eubacteria-like endosymbionts; however, the origin of the mitochondrion remains a subject of debate. In this study, we investigated the phenomenon of chimerism in mitochondria to shed light on the origin of these organelles by determining which species played a role in their formation. We used the mitochondria of four distinct organisms, Reclinomonas americana, Homo sapiens, Saccharomyces cerevisiae and multichromosome Pediculus humanus, and attempted to identify the origin of each mitochondrial gene. Our results suggest that the origin of mitochondrial genes is not limited to the Rickettsiales and that the creation of these genes did not occur in a single event, but through multiple successive events. Some of these events are very old and were followed by events that are more recent and occurred through the addition of elements originating from current species. The points in time that the elements were added and the parental species of each gene in the mitochondrial genome are different to the individual species. These data constitute strong evidence that mitochondria do not have a single common ancestor but likely have numerous ancestors, including proto-Rickettsiales, proto-Rhizobiales and proto-Alphaproteobacteria, as well as current alphaproteobacterial species. The analysis of the multichromosome P. humanus mitochondrion supports this mechanism. The most plausible scenario of the origin of the mitochondrion is that ancestors of Rickettsiales and Rhizobiales merged in a proto-eukaryotic cell approximately one billion years ago. The fusion of the Rickettsiales and Rhizobiales cells was followed by gene loss, genomic rearrangements and the addition of alphaproteobacterial elements through ancient and more recent recombination events. Each gene of each of the four studied mitochondria has a different origin, while in some cases, multichromosomes may allow for enhanced gene exchange. Therefore, the tree of life is not sufficient to explain the chimeric structure of current genomes, and the theory of a single common ancestor and a top-down tree does not reflect our current state of knowledge. Mitochondrial evolution constitutes a rhizome, and it should be represented as such.

Genotyping of Human Lice Suggests Multiple Emergences of Body Lice from Local Head Louse Populations

PubMed Central

Li, Wenjun; Ortiz, Gabriel; Fournier, Pierre-Edouard; Gimenez, Gregory; Reed, David L.; Pittendrigh, Barry; Raoult, Didier

2010-01-01

Background Genetic analyses of human lice have shown that the current taxonomic classification of head lice (Pediculus humanus capitis) and body lice (Pediculus humanus humanus) does not reflect their phylogenetic organization. Three phylotypes of head lice A, B and C exist but body lice have been observed only in phylotype A. Head and body lice have different behaviours and only the latter have been involved in outbreaks of infectious diseases including epidemic typhus, trench fever and louse borne recurrent fever. Recent studies suggest that body lice arose several times from head louse populations. Methods and Findings By introducing a new genotyping technique, sequencing variable intergenic spacers which were selected from louse genomic sequence, we were able to evaluate the genotypic distribution of 207 human lice. Sequence variation of two intergenic spacers, S2 and S5, discriminated the 207 lice into 148 genotypes and sequence variation of another two intergenic spacers, PM1 and PM2, discriminated 174 lice into 77 genotypes. Concatenation of the four intergenic spacers discriminated a panel of 97 lice into 96 genotypes. These intergenic spacer sequence types were relatively specific geographically, and enabled us to identify two clusters in France, one cluster in Central Africa (where a large body louse outbreak has been observed) and one cluster in Russia. Interestingly, head and body lice were not genetically differentiated. Conclusions We propose a hypothesis for the emergence of body lice, and suggest that humans with both low hygiene and head louse infestations provide an opportunity for head louse variants, able to ingest a larger blood meal (a required characteristic of body lice), to colonize clothing. If this hypothesis is ultimately supported, it would help to explain why poor human hygiene often coincides with outbreaks of body lice. Additionally, if head lice act as a reservoir for body lice, and that any social degradation in human populations may allow the formation of new populations of body lice, then head louse populations are potentially a greater threat to humans than previously assumed. PMID:20351779

High Ancient Genetic Diversity of Human Lice, Pediculus humanus, from Israel Reveals New Insights into the Origin of Clade B Lice.

PubMed

Amanzougaghene, Nadia; Mumcuoglu, Kosta Y; Fenollar, Florence; Alfi, Shir; Yesilyurt, Gonca; Raoult, Didier; Mediannikov, Oleg

2016-01-01

The human head louse, Pediculus humanus capitis, is subdivided into several significantly divergent mitochondrial haplogroups, each with particular geographical distributions. Historically, they are among the oldest human parasites, representing an excellent marker for tracking older events in human evolutionary history. In this study, ancient DNA analysis using real-time polymerase chain reaction (qPCR), combined with conventional PCR, was applied to the remains of twenty-four ancient head lice and their eggs from the Roman period which were recovered from Israel. The lice and eggs were found in three combs, one of which was recovered from archaeological excavations in the Hatzeva area of the Judean desert, and two of which found in Moa, in the Arava region, close to the Dead Sea. Results show that the head lice remains dating approximately to 2,000 years old have a cytb haplogroup A, which is worldwide in distribution, and haplogroup B, which has thus far only been found in contemporary lice from America, Europe, Australia and, most recently, Africa. More specifically, this haplogroup B has a B36 haplotype, the most common among B haplogroups, and has been present in America for at least 4,000 years. The present findings confirm that clade B lice existed, at least in the Middle East, prior to contacts between Native Americans and Europeans. These results support a Middle Eastern origin for clade B followed by its introduction into the New World with the early peoples. Lastly, the presence of Acinetobacter baumannii DNA was demonstrated by qPCR and sequencing in four head lice remains belonging to clade A.

Human pediculosis: a critical health problem and what about nursing policy?

PubMed

El-Bahnasawy, Mamdouh M; Abdel, Fadil Eman Ebrahim; Morsy, Tosson A

2012-12-01

Lice infestation on the human body (also known as pediculosis) is very common. Cases number in the hundreds of millions worldwide. Three distinct presentations of lice infection exist and each is caused by a unique parasite. Head lice (Pediculus humanus capitis) is by far and away the most common infestation and favors no particular socioeconomic group. A genetically close "cousin," Pediculus humanus corporis, is responsible for body lice and is more commonly associated with poverty, overcrowding, and poor hygiene. Pubic lice (crabs) are caused by Pthirus pubis and is transmitted by intimate and/or sexual contact. No doubt, human lice infestation is an increasing problem worldwide, Apart from being an irritating and a shaming human ecto-parasite, they transmit serious infectious diseases; epidemic or classical typhus, epidemic relapsing fever as well as Trench fever. Eradication of lice infestation prevents transmission of infectious diseases. People who live and work in close proximity to louse-infested individuals may secondarily acquire lice even if they regularly wash their clothes and have good hygiene. Thus, all louse-infested persons and workers in close contact with such persons should periodically inspected and use long-acting safe insecticides. Human lice can be treated with agents such as DDT, malathion, and lindane, but reports of resistance to one or more of them have recently appeared. Pyrethroid permethrin when applied as a dust or spray to clothing or bedding is highly effective against lice and is the delousing agent of choice. Fabric treated with permethrin retains toxicity to lice even after 20 washings, thereby offering significant long-term passive protection against epidemic typhus. Itching may continue even after all lice are destroyed. This happens because of a lingering allergic reactionto their bites. Over-the-counter cortisone (corticosteroid) creams or calamine lotion may help.

In vitro pediculicidal activity of herbal shampoo base on Thai local plants against head louse (Pediculus humanus capitis De Geer).

PubMed

Rassami, Watcharawit; Soonwera, Mayura

2013-04-01

Head lice infestation, a worldwide head infestation caused Pediculus humanus capitis De Geer, is an important public health problem in Thailand. Several chemical pediculicides have lost in efficacy due to increasing resistance of lice against insecticide. Therefore, non-toxic alternative products, such as natural products from plants, e.g. plant extract pediculicides, are needed for head lice control. The aims of this study were to evaluate the potential of pediculicidal activity of herbal shampoo base on three species of Thai local plants (Accacia concinna (Willd.) DC, Averrhoa bilimbi Linn. and Tamarindus indica Linn.) against head lice and to compare them with carbaryl shampoo (Hafif shampoo®; 0.6% w/v carbaryl) and non-treatment control in order to assess their in vitro. Doses of 0.12 and 0.25 ml/cm2 of each herbal shampoo were applied to filter paper, and ten head lice were place on the filter paper. The mortalities of head lice on the filter paper were recorded at 1, 5, 10, 30 and 60 min by sterio-microscope. All herbal shampoos at 0.25 ml/cm2 were more effective pediculicide than carbaryl shampoo with 100% mortality at 5 min. The median lethal time (LT50) of all herbal shampoos at 0.25 ml/cm2 showed no significant differences over at 0.12 ml/cm2 (P<0.01). The most effective pediculicide was T. indica extract shampoo, followed by Av. bilimbi extract shampoo and Ac. concinna extract shampoo, with LT50 values<1.0 min. Our data showed that all herbal shampoos have high potential of pediculicide to head lice treatments for schoolchildren.

High Ancient Genetic Diversity of Human Lice, Pediculus humanus, from Israel Reveals New Insights into the Origin of Clade B Lice

PubMed Central

Amanzougaghene, Nadia; Mumcuoglu, Kosta Y.; Fenollar, Florence; Alfi, Shir; Yesilyurt, Gonca; Raoult, Didier; Mediannikov, Oleg

2016-01-01

The human head louse, Pediculus humanus capitis, is subdivided into several significantly divergent mitochondrial haplogroups, each with particular geographical distributions. Historically, they are among the oldest human parasites, representing an excellent marker for tracking older events in human evolutionary history. In this study, ancient DNA analysis using real-time polymerase chain reaction (qPCR), combined with conventional PCR, was applied to the remains of twenty-four ancient head lice and their eggs from the Roman period which were recovered from Israel. The lice and eggs were found in three combs, one of which was recovered from archaeological excavations in the Hatzeva area of the Judean desert, and two of which found in Moa, in the Arava region, close to the Dead Sea. Results show that the head lice remains dating approximately to 2,000 years old have a cytb haplogroup A, which is worldwide in distribution, and haplogroup B, which has thus far only been found in contemporary lice from America, Europe, Australia and, most recently, Africa. More specifically, this haplogroup B has a B36 haplotype, the most common among B haplogroups, and has been present in America for at least 4,000 years. The present findings confirm that clade B lice existed, at least in the Middle East, prior to contacts between Native Americans and Europeans. These results support a Middle Eastern origin for clade B followed by its introduction into the New World with the early peoples. Lastly, the presence of Acinetobacter baumannii DNA was demonstrated by qPCR and sequencing in four head lice remains belonging to clade A. PMID:27741281

Use of a poultry model to assess the transfer inhibition effect of head lice (Pediculus humanus capitis) products.

PubMed

Ketzis, Jennifer K; Clements, Kathleen; Honraet, Kris

2014-05-01

Head lice (Pediculus humanus capitis) remain a nuisance, predominantly in school age children. Despite the availability of pediculicidal products, children, after treatment, easily become re-infested if the outbreak has not been controlled on a class or school level. Lice repellents and re-infestation deterrents have been developed to protect children post-treatment. In vitro assays, which are used to evaluate the performance of these products, have limited correlation to in vivo efficacy. In this study, a chicken model was developed as an alternative to in vitro models, more closely mimicking the in vivo situation of children at school. Chickens with natural infestations of Menopon spp. and Menacanthus spp. were divided into three groups and co-housed for 23 h: Group 1 was treated with a commercial product designed to kill lice and protect from re-infestation (Oystershell Laboratories); group 2 was used to assess lice re-population onto lice-free, untreated chickens; and group 3, the seeder group, consisted of lice-infested chickens. The chickens were examined for lice before and at regular intervals after treatment. The group 1 chickens had an average of 40 lice pre-treatment, 0 lice post-treatment and did not become re-infested during the 23-h period. Lice were slow to re-populate the group 2 chickens but were seen 3 h after co-housing with an average of 6 lice each at the end of the study. Group 3 chickens maintained their lice throughout the study (average of 32 at end of study). Based on this study, chickens can be used as a model to test the performance of lice repellents and re-infestation deterrents.

Treatment of head lice (Pediculus humanus capitis) infestation: is regular combing alone with a special detection comb effective at all levels?

PubMed

Kurt, Özgür; Balcıoğlu, I Cüneyt; Limoncu, M Emin; Girginkardeşler, Nogay; Arserim, Süha K; Görgün, Serhan; Oyur, Tuba; Karakuş, Mehmet; Düzyol, Didem; Gökmen, Aysegül Aksoy; Kitapçıoğlu, Gül; Özbel, Yusuf

2015-04-01

Head lice infestation (HLI) caused by Pediculus humanus capitis has been a public health problem worldwide. Specially designed combs are used to identify head lice, while anti-lice products are applied on the scalp for treatment. In the present study, we aimed to test whether combing only by precision detection comb (PDC) or metal pin comb (MPC) could be effective alternatives to the use of anti-lice products in children. A total of 560 children from two rural schools in Turkey were screened. In the PDC trial, children were combed every second day for 14 days, while in the MPC trial, combing was performed once in every four days for 15 days. Children were divided into two groups (dry combing and wet combing) for both trials and results were compared. The results showed no significant differences between dry and wet combing strategies for both combs for the removal of head lice (p > 0.05). The number of adult head lice declined significantly on each subsequent combing day in both approaches, except on day 15 in the MPC trial. In the end, no louse was found in 54.1 and 48.9% of children in the PDC and MPC trials, respectively. Since family members of infested children were not available, they were not checked for HLI. Four times combing within 2 weeks with MPC combs was found effective for both treatment of low HLI and prevention of heavy HLI. In conclusion, regular combing by special combs decreases HLI level in children and is safely applicable as long-term treatment.

[Understanding mitochondrial genome fragmentation in parasitic lice (Insecta: Phthiraptera)].

PubMed

Dong, Wen-Ge; Guo, Xian-Guo; Jin, Dao-Chao; Xue, Shi-Peng; Qin, Feng; Simon, Song; Stephen, C Barker; Renfu, Shao

2013-07-01

Lice are obligate ectoparasites of mammals and birds. Extensive fragmentation of mitochondrial genomes has been found in some louse species in the families Pediculidae, Pthiridae, Philopteridae and Trichodectidae. For example, the mt genomes of human body louse (Pediculus humanus), head louse (Pediculus capitis), and public louse (Pthirus pubis) have 20, 20 and 14 mini-chromosomes, respectively. These mini-chromosomes might be the results of deletion and recombination of mt genes. The factors and mechanisms of mitochondrial genome fragmentation are currently unknown. The fragmentation might be the results of evolutionary selection or random genetic drift or it is probably related to the lack of mtSSB (mitochondrial single-strand DNA binding protein). Understanding the fragmentation of mitochondrial genomes is of significance for understanding the origin and evolution of mitochondria. This paper reviews the recent advances in the studies of mito-chondrial genome fragmentation in lice, including the phenomena of mitochondrial genome fragmentation, characteristics of fragmented mitochondrial genomes, and some factors and mechanisms possibly leading to the mitochondrial genome fragmentation of lice. Perspectives for future studies on fragmented mt genomes are also discussed.

VectorBase: a data resource for invertebrate vector genomics

PubMed Central

Lawson, Daniel; Arensburger, Peter; Atkinson, Peter; Besansky, Nora J.; Bruggner, Robert V.; Butler, Ryan; Campbell, Kathryn S.; Christophides, George K.; Christley, Scott; Dialynas, Emmanuel; Hammond, Martin; Hill, Catherine A.; Konopinski, Nathan; Lobo, Neil F.; MacCallum, Robert M.; Madey, Greg; Megy, Karine; Meyer, Jason; Redmond, Seth; Severson, David W.; Stinson, Eric O.; Topalis, Pantelis; Birney, Ewan; Gelbart, William M.; Kafatos, Fotis C.; Louis, Christos; Collins, Frank H.

2009-01-01

VectorBase (http://www.vectorbase.org) is an NIAID-funded Bioinformatic Resource Center focused on invertebrate vectors of human pathogens. VectorBase annotates and curates vector genomes providing a web accessible integrated resource for the research community. Currently, VectorBase contains genome information for three mosquito species: Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus, a body louse Pediculus humanus and a tick species Ixodes scapularis. Since our last report VectorBase has initiated a community annotation system, a microarray and gene expression repository and controlled vocabularies for anatomy and insecticide resistance. We have continued to develop both the software infrastructure and tools for interrogating the stored data. PMID:19028744

Treatment of pediculosis capitis infested children with 1% permethrin shampoo in Turkey.

PubMed

Yazar, Suleyman; Sahin, Izzet

2005-10-01

Pediculosis capitis (head lice) is an infestation that affects many children. Although, there are a number of different treatment modalities, at the present study, we investigated the efficacy of permethrin in the treatment of pediculosis capitis in children. This study was carried out in 3 village primary schools in the Kayseri region involving 185 of 712 school children infested with Pediculus humanus capitis during a survey conducted in March 2001. It was found that 173 (97.29%) of the 178 students who applied the prescribed medications were cured, indicating that interestingly 1% permethrin shampoo (Kwellada) is an effective and safe treatment choice for pediculosis capitis.

Human ectoparasites and the spread of plague in Europe during the Second Pandemic

PubMed Central

Krauer, Fabienne; Walløe, Lars; Bramanti, Barbara; Stenseth, Nils Chr.; Schmid, Boris V.

2018-01-01

Plague, caused by the bacterium Yersinia pestis, can spread through human populations by multiple transmission pathways. Today, most human plague cases are bubonic, caused by spillover of infected fleas from rodent epizootics, or pneumonic, caused by inhalation of infectious droplets. However, little is known about the historical spread of plague in Europe during the Second Pandemic (14–19th centuries), including the Black Death, which led to high mortality and recurrent epidemics for hundreds of years. Several studies have suggested that human ectoparasite vectors, such as human fleas (Pulex irritans) or body lice (Pediculus humanus humanus), caused the rapidly spreading epidemics. Here, we describe a compartmental model for plague transmission by a human ectoparasite vector. Using Bayesian inference, we found that this model fits mortality curves from nine outbreaks in Europe better than models for pneumonic or rodent transmission. Our results support that human ectoparasites were primary vectors for plague during the Second Pandemic, including the Black Death (1346–1353), ultimately challenging the assumption that plague in Europe was predominantly spread by rats. PMID:29339508

In Vitro Screening of Anti-lice Activity of Pongamia pinnata Leaves

PubMed Central

Radhamani, Suraj; Gopinath, Rejitha; Kalusalingam, Anandarajagopal; Vimala, Anita Gnana Kumari Anbumani; Husain, Hj Azman

2009-01-01

Growing patterns of pediculocidal drug resistance towards head louse laid the foundation for research in exploring novel anti-lice agents from medicinal plants. In the present study, various extracts of Pongamia pinnata leaves were tested against the head louse Pediculus humanus capitis. A filter paper diffusion method was conducted for determining the potential pediculocidal and ovicidal activity of chloroform, petroleum ether, methanol, and water extracts of P. pinnata leaves. The findings revealed that petroleum ether extracts possess excellent anti-lice activity with values ranging between 50.3% and 100% where as chloroform and methanol extracts showed moderate pediculocidal effects. The chloroform and methanol extracts were also successful in inhibiting nymph emergence and the petroleum ether extract was the most effective with a complete inhibition of emergence. Water extract was devoid of both pediculocidal and ovicidal activities. All the results were well comparable with benzoyl benzoate (25% w/v). These results showed the prospect of using P. pinnata leave extracts against P. humanus capitis in difficult situations of emergence of resistance to synthetic anti-lice agents. PMID:19967085

Human ectoparasites and the spread of plague in Europe during the Second Pandemic.

PubMed

Dean, Katharine R; Krauer, Fabienne; Walløe, Lars; Lingjærde, Ole Christian; Bramanti, Barbara; Stenseth, Nils Chr; Schmid, Boris V

2018-02-06

Plague, caused by the bacterium Yersinia pestis , can spread through human populations by multiple transmission pathways. Today, most human plague cases are bubonic, caused by spillover of infected fleas from rodent epizootics, or pneumonic, caused by inhalation of infectious droplets. However, little is known about the historical spread of plague in Europe during the Second Pandemic (14-19th centuries), including the Black Death, which led to high mortality and recurrent epidemics for hundreds of years. Several studies have suggested that human ectoparasite vectors, such as human fleas ( Pulex irritans ) or body lice ( Pediculus humanus humanus ), caused the rapidly spreading epidemics. Here, we describe a compartmental model for plague transmission by a human ectoparasite vector. Using Bayesian inference, we found that this model fits mortality curves from nine outbreaks in Europe better than models for pneumonic or rodent transmission. Our results support that human ectoparasites were primary vectors for plague during the Second Pandemic, including the Black Death (1346-1353), ultimately challenging the assumption that plague in Europe was predominantly spread by rats. Copyright © 2018 the Author(s). Published by PNAS.

Acaricidal, pediculicidal and larvicidal activity of synthesized ZnO nanoparticles using Momordica charantia leaf extract against blood feeding parasites.

PubMed

Gandhi, P Rajiv; Jayaseelan, C; Mary, R Regina; Mathivanan, D; Suseem, S R

2017-10-01

The aim of the present study was to evaluate the acaricidal, pediculicidal and larvicidal effect of synthesized zinc oxide nanoparticles (ZnO NPs) using Momordica charantia leaf extract against the larvae of Rhipicephalus (Boophilus) microplus, adult of Pediculus humanus capitis, and the larvae of Anopheles stephensi, Culex quinquefasciatus. The ZnO NPs were characterized by using UV, XRD, FTIR and SEM-EDX. The SEM image confirms that the synthesized nanoparticles were spherical in shape with a size of 21.32 nm. The results of GC-MS analysis indicates the presence of the major compound of Nonacosane (C 29 H 60 ) in the M. charantia leaf extract. Cattle tick, head lice and mosquito larvae were exposed to a varying concentrations of the synthesized ZnO NPs and M. charantia leaf extract for 24 h. Compared to the leaf aqueous extract, biosynthesized ZnO NPs showed higher toxicity against R. microplus, P. humanus capitis, An. stephensi, and Cx. Quinquefasciatus with the LC 50 values of 6.87, 14.38, 5.42, and 4.87 mg/L, respectively. The findings revealed that synthesized ZnO NPs possess excellent anti-parasitic activity. These results suggest that the green synthesized ZnO NPs has the potential to be used as an ideal ecofriendly approach for the control of R. microplus, P. humanus capitis and the mosquito larvae of An. Stephensi and Cx. quinquefasciatus. Copyright © 2017 Elsevier Inc. All rights reserved.

Body lice of homeless people reveal the presence of several emerging bacterial pathogens in northern Algeria.

PubMed

Louni, Meriem; Mana, Nassima; Bitam, Idir; Dahmani, Mustapha; Parola, Philippe; Fenollar, Florence; Raoult, Didier; Mediannikov, Oleg

2018-04-01

Human lice, Pediculus humanus, are obligate blood-sucking parasites. Body lice, Pediculus h. humanus, occur in two divergent mitochondrial clades (A and D) each exhibiting a particular geographic distribution. Currently, the body louse is recognized as the only vector for louse-borne diseases. In this study, we aimed to study the genetic diversity of body lice collected from homeless populations in three localities of northern Algeria, and to investigate louse-borne pathogens in these lice. In this study, 524 body lice specimens were collected from 44 homeless people in three localities: Algiers, Tizi Ouzou and Boumerdès located in northern Algeria. Duplex clade specific real-time PCRs (qPCR) and Cytochrome b (cytb) mitochondrial DNA (mtDNA) analysis were performed in order to identify the mitochondrial clade. Screening of louse-borne pathogens bacteria was based on targeting specific genes for each pathogen using qPCR supplemented by sequencing. All body lice belong to clade A. Through amplification and sequencing of the cytb gene we confirmed the presence of three haplotypes: A5, A9 and A63, which is novel. The molecular investigation of the 524 body lice samples revealed the presence of four human pathogens: Bartonella quintana (13.35%), Coxiella burnetii (10.52%), Anaplasma phagocytophilum (0.76%) and Acinetobacter species (A. baumannii, A. johnsonii, A. berezeniae, A. nosocomialis and A. variabilis, in total 46.94%). To the best of our knowledge, our study is the first to show the genetic diversity and presence of several emerging pathogenic bacteria in homeless' body lice from Algeria. We also report for the first time, the presence of several species of Acinetobacter in human body lice. Our results highlight the fact that body lice may be suspected as being a much broader vector of several pathogenic agents than previously thought. Nevertheless, other studies are needed to encourage epidemiological investigations and surveys of louse-associated infections.

An experimental model of human body louse infection with Rickettsia typhi.

PubMed

Houhamdi, Linda; Fournier, Pierre-Edouard; Fang, Rong; Raoult, Didier

2003-06-01

Murine (endemic) typhus caused by Rickettsia typhi, one of the most widely distributed arthropod-borne diseases, is transmitted to humans mainly by the oriental rat flea. The human body louse, Pediculus humanus corporis, has been suspected to have a role in the transmission of R. typhi to humans. To evaluate the potential role of Pediculus humanus corporis as a vector of murine typhus, we used R. typhi in an experimental model of human body louse infection previously used with R. prowazekii. A rabbit was made bacteremic by inoculating it with 2 x 10(6) plaque-forming units of R. typhi; it remained bacteremic for at least 59 hours. Two hundred body lice infected by feeding on the bacteremic rabbit were compared to 200 uninfected control lice. Each louse population was fed once a day on the abdomen of a seronegative rabbit. On day 8 post-infection, as a result of disruption of the gut cells and leakage of the blood meal into the hemolymph, four infected lice became bright red and died within four hours. The life span of infected lice was 20 days less than that of the controls. Infected lice did not transmit R. typhi to their progeny (eggs and larvae) as demonstrated by PCR amplification and cell culture. With an immunofluorescence assay, R. typhi was detected in feces from day 7 post-infection, and the organism remained viable in feces for up to 80 days as demonstrated by cell culture. From the 21st day post-infection, the rabbit used to feed the R. typhi-infected lice developed an immunoglobulin response with a titer of 1:50 increasing to 1:200 at the 42nd day post-infection. It showed no clinical signs of infection. The rabbit that was used to feed uninfected lice remained seronegative. Although body lice are not clearly identified vectors of R. typhi, it seems that under certain circumstances they could transmit R. typhi.

Effectiveness of isopropyl myristate/cyclomethicone D5 solution of removing cuticular hydrocarbons from human head lice (Pediculus humanus capitis)

PubMed Central

2012-01-01

Background In the treatment of human head lice infestation, healthcare providers are increasingly concerned about lice becoming resistant to existing pesticide treatments. Traditional pesticides, used to control these pests, have a neurological mechanism of action. This publication describes a topical solution with a non-traditional mechanism of action, based on physical disruption of the wax layer that covers the cuticle of the louse exoskeleton. This topical solution has been shown clinically to cure 82% of patients with only a 10-minute treatment time, repeated once after 7 days. All insects, including human head lice, have a wax-covered exoskeleton. This wax, composed of hydrocarbons, provides the insect with protection against water loss and is therefore critical to its survival. When the protective wax is disrupted, water loss becomes uncontrollable and irreversible, leading to dehydration and death. A specific pattern of hydrocarbons has been found in all of the head louse cuticular wax studied. Iso-octane effectively removes these hydrocarbons from human head lice’s cuticular wax. Methods A method of head louse cuticle wax extraction and analysis by gas chromatography was developed. Human head lice (Pediculus humanus capitis) were collected from infested patients and subjected to any of three extraction solvents comprising either the test product or one of two solvents introduced as controls. A gas chromatograph equipped with a flame ionization detector (GC/FID) was used to determine the presence of hydrocarbons in the three head lice extracts. Results In the study reported herein, the test product isopropyl myristate/cyclomethicone D5 (IPM/D5) was shown to perform comparably with iso-octane, effectively extracting the target hydrocarbons from the cuticular wax that coats the human head louse exoskeleton. Conclusions Disruption of the integrity of the insect cuticle by removal of specific hydrocarbons found in the cuticular wax appears to offer a mechanism for killing lice without the likelihood of encountering genetic resistance. PMID:22943314

Effectiveness of isopropyl myristate/cyclomethicone D5 solution of removing cuticular hydrocarbons from human head lice (Pediculus humanus capitis).

PubMed

Barnett, Eric; Palma, Kathleen G; Clayton, Bert; Ballard, Timothy

2012-09-03

In the treatment of human head lice infestation, healthcare providers are increasingly concerned about lice becoming resistant to existing pesticide treatments. Traditional pesticides, used to control these pests, have a neurological mechanism of action. This publication describes a topical solution with a non-traditional mechanism of action, based on physical disruption of the wax layer that covers the cuticle of the louse exoskeleton. This topical solution has been shown clinically to cure 82% of patients with only a 10-minute treatment time, repeated once after 7 days. All insects, including human head lice, have a wax-covered exoskeleton. This wax, composed of hydrocarbons, provides the insect with protection against water loss and is therefore critical to its survival. When the protective wax is disrupted, water loss becomes uncontrollable and irreversible, leading to dehydration and death. A specific pattern of hydrocarbons has been found in all of the head louse cuticular wax studied. Iso-octane effectively removes these hydrocarbons from human head lice's cuticular wax. A method of head louse cuticle wax extraction and analysis by gas chromatography was developed. Human head lice (Pediculus humanus capitis) were collected from infested patients and subjected to any of three extraction solvents comprising either the test product or one of two solvents introduced as controls. A gas chromatograph equipped with a flame ionization detector (GC/FID) was used to determine the presence of hydrocarbons in the three head lice extracts. In the study reported herein, the test product isopropyl myristate/cyclomethicone D5 (IPM/D5) was shown to perform comparably with iso-octane, effectively extracting the target hydrocarbons from the cuticular wax that coats the human head louse exoskeleton. Disruption of the integrity of the insect cuticle by removal of specific hydrocarbons found in the cuticular wax appears to offer a mechanism for killing lice without the likelihood of encountering genetic resistance.

Body lice of homeless people reveal the presence of several emerging bacterial pathogens in northern Algeria

PubMed Central

Louni, Meriem; Mana, Nassima; Bitam, Idir; Dahmani, Mustapha; Parola, Philippe; Fenollar, Florence; Raoult, Didier

2018-01-01

Background Human lice, Pediculus humanus, are obligate blood-sucking parasites. Body lice, Pediculus h. humanus, occur in two divergent mitochondrial clades (A and D) each exhibiting a particular geographic distribution. Currently, the body louse is recognized as the only vector for louse-borne diseases. In this study, we aimed to study the genetic diversity of body lice collected from homeless populations in three localities of northern Algeria, and to investigate louse-borne pathogens in these lice. Methodology/Principal findings In this study, 524 body lice specimens were collected from 44 homeless people in three localities: Algiers, Tizi Ouzou and Boumerdès located in northern Algeria. Duplex clade specific real-time PCRs (qPCR) and Cytochrome b (cytb) mitochondrial DNA (mtDNA) analysis were performed in order to identify the mitochondrial clade. Screening of louse-borne pathogens bacteria was based on targeting specific genes for each pathogen using qPCR supplemented by sequencing. All body lice belong to clade A. Through amplification and sequencing of the cytb gene we confirmed the presence of three haplotypes: A5, A9 and A63, which is novel. The molecular investigation of the 524 body lice samples revealed the presence of four human pathogens: Bartonella quintana (13.35%), Coxiella burnetii (10.52%), Anaplasma phagocytophilum (0.76%) and Acinetobacter species (A. baumannii, A. johnsonii, A. berezeniae, A. nosocomialis and A. variabilis, in total 46.94%). Conclusions/Significance To the best of our knowledge, our study is the first to show the genetic diversity and presence of several emerging pathogenic bacteria in homeless’ body lice from Algeria. We also report for the first time, the presence of several species of Acinetobacter in human body lice. Our results highlight the fact that body lice may be suspected as being a much broader vector of several pathogenic agents than previously thought. Nevertheless, other studies are needed to encourage epidemiological investigations and surveys of louse-associated infections. PMID:29664950

Odorant receptor-based discovery of natural repellents of human lice.

PubMed

Pelletier, Julien; Xu, Pingxi; Yoon, Kyong S; Clark, John M; Leal, Walter S

2015-11-01

The body louse, Pediculus humanus humanus, is an obligate blood-feeding ectoparasite and an important insect vector that mediates the transmission of diseases to humans. The analysis of the body louse genome revealed a drastic reduction of the chemosensory gene repertoires when compared to other insects, suggesting specific olfactory adaptations to host specialization and permanent parasitic lifestyle. Here, we present for the first time functional evidence for the role of odorant receptors (ORs) in this insect, with the objective to gain insight into the chemical ecology of this vector. We identified seven putative full-length ORs, in addition to the odorant receptor co-receptor (Orco), and expressed four of them in the Xenopus laevis oocytes system. When screened with a panel of ecologically-relevant odorants, PhumOR2 responded to a narrow set of compounds. At the behavior level, both head and body lice were repelled by the physiologically-active chemicals. This study presents the first evidence of the OR pathway being functional in lice and identifies PhumOR2 as a sensitive receptor of natural repellents that could be used to develop novel efficient molecules to control these insects. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Les infestations par les poux de tête : une mise à jour clinique.

PubMed

Cummings, Carl; Finlay, Jane C; MacDonald, Noni E

2018-02-01

Les infestations par les poux de tête ( Pediculus humanus capitis ) ne constituent ni un risque sanitaire primaire ni un vecteur de maladie, mais représentent plutôt un problème de société au coût impor- tant. Pour diagnostiquer une infestation, il faut déceler un pou vivant. Même si les pyréthines et la perméthrine demeurent les traitements de première intention au Canada, la solution de myristate d'isopropyle et de ST-cyclométhicone et la diméticone peuvent être envisagées en deuxième intention après un échec thérapeutique démontré.

What's in a name: the taxonomic status of human head and body lice.

PubMed

Light, Jessica E; Toups, Melissa A; Reed, David L

2008-06-01

Human head lice (Anoplura: Pediculidae: Pediculus) are pandemic, parasitizing countless school children worldwide due to the evolution of insecticide resistance, and human body (clothing) lice are responsible for the deaths of millions as a result of vectoring several deadly bacterial pathogens. Despite the obvious impact these lice have had on their human hosts, it is unclear whether head and body lice represent two morphological forms of a single species or two distinct species. To assess the taxonomic status of head and body lice, we provide a synthesis of publicly available molecular data in GenBank, and we compare phylogenetic and population genetic methods using the most diverse geographic and molecular sampling presently available. Our analyses find reticulated networks, gene flow, and a lack of reciprocal monophyly, all of which indicate that head and body lice do not represent genetically distinct evolutionary units. Based on these findings, as well as inconsistencies of morphological, behavioral, and ecological variability between head and body lice, we contend that no known species concept would recognize these louse morphotypes as separate species. We recommend recognizing head and body lice as morphotypes of a single species, Pediculus humanus, until compelling new data and analyses (preferably analyses of fast evolving nuclear markers in a coalescent framework) indicate otherwise.

The mitochondrial genome of the chimpanzee louse, Pediculus schaeffi: insights into the process of mitochondrial genome fragmentation in the blood-sucking lice of great apes.

PubMed

Herd, Kate E; Barker, Stephen C; Shao, Renfu

2015-09-03

Blood-sucking lice in the genera Pediculus and Pthirus are obligate ectoparasites of great apes. Unlike most bilateral animals, which have 37 mitochondrial (mt) genes on a single circular chromosome, the sucking lice of humans have extensively fragmented mt genomes. The head louse, Pediculus capitis, and the body louse, Pe. humanus, have their 37 mt genes on 20 minichromosomes. The pubic louse, Pthirus pubis, has its 34 mt genes known on 14 minichromosomes. To understand the process of mt genome fragmentation in the sucking lice of great apes, we sequenced the mt genome of the chimpanzee louse, Pe. schaeffi, and compared it with the three human lice. We identified all of the 37 mt genes typical of bilateral animals in the chimpanzee louse; these genes are on 18 types of minichromosomes. Seventeen of the 18 minichromosomes of the chimpanzee louse have the same gene content and gene arrangement as their counterparts in the human head louse and the human body louse. However, five genes, cob, trnS 1 , trnN, trnE and trnM, which are on three minichromosomes in the human head louse and the human body louse, are together on one minichromosome in the chimpanzee louse. Using the human pubic louse, Pt. pubis, as an outgroup for comparison, we infer that a single minichromosome has fragmented into three in the lineage leading to the human head louse and the human body louse since this lineage diverged from the chimpanzee louse ~6 million years ago. Our results provide insights into the process of mt genome fragmentation in the sucking lice in a relatively fine evolutionary scale.

Use of temperature and water immersion to control the human body louse (Anoplura: Pediculidae).

PubMed

Mumcuoglu, K Y; Friger, M; Cohen, R

2006-07-01

Physical methods such as high and low temperatures were used in the past for the control of human body louse, Pediculus humanus humanus L. (Anoplura: Pediculidae). In the current study, the minimum time necessary to kill all lice after exposing them to temperatures other than those described in the literature, the mortality of lice after immersing them in water, and the survival of lice whose legs were amputated were studied. All lice died after 6 d at 6 degrees C, after 11 d at 24 degrees C, and after 9 d at 31 degrees C. At -17 degrees C, all lice were dead after 35 min, whereas at -70 degrees C, all lice were dead after 1 min. All lice died after immersion in water within 19 h. The differences in mortality were significant but borderline between controls and lice whose two legs were amputated immediately or 24 h after feeding (3.3 versus 13.3% and 8.3 versus 21.7%). For lice whose leg was amputated 48 h after feeding, significant differences were found between controls and lice with one amputated leg (13.3 versus 48.3%), between controls and lice with two amputated legs (13.3 versus 68.3%), and between lice with one and two amputated legs (48.3 versus 68.3%).

Experimentally infected human body lice (pediculus humanus humanus) as vectors of Rickettsia rickettsii and Rickettsia conorii in a rabbit model.

PubMed

Houhamdi, Linda; Raoult, Didier

2006-04-01

The human body louse, the natural vector of Rickettsia prowazekii, is able to experimentally transmit the normally flea-borne rickettsia R. typhi, suggesting that the relationships between the body louse and rickettsiae are not specific. We used our experimental infection model to test the ability of body lice to transmit two prevalent tick-borne rickettsiae. Each of two rabbits was made bacteremic by injecting intravenously 2 x 10(6) plaque-forming units of either R. rickettsii or R. conorii. Four hundred body lice were infected by feeding on the bacteremic rabbit and were compared with 400 uninfected lice. Each louse group was fed once a day on a separate seronegative rabbit. The survival of infected lice was not different from that of uninfected controls. Lice remained infected for their lifespan, excreted R. rickettsii and R. conorii in their feces, but did not transmit the infection to their progeny. The nurse rabbit of uninfected lice remained asymptomatic and seronegative. Those rabbits used to feed infected lice developed bacteremia and seroconverted. Although the body louse is not a known vector of spotted fevers, it was able in our study to acquire, maintain, and transmit both R. rickettsii and R. conorii.

An incurable itch

PubMed Central

Smith, Christine H.; Goldman, Ran D.

2012-01-01

Abstract Question Head lice infestations continue to be seen frequently in many communities. Some of these children require multiple treatments before eradication. What are the current treatment recommendations for head lice? Answer Head lice (Pediculus humanus capitis) infestations are common, particularly among school-aged children. In order to minimize louse resistance, insecticide usage, and social stigmatization, diagnosis and treatment should be limited to those with live lice on the scalp. Options for management are predominantly topical therapies or physical removal. Large studies comparing the efficacy of these treatments are lacking. Treatment should be repeated in approximately 7 days if topical insecticides are used or every 2 to 3 days for 2 weeks if wet combing is used. Lice resistance patterns vary widely geographically, and resistance is now the most common cause of treatment failure. PMID:22893334

An incurable itch: head lice.

PubMed

Smith, Christine H; Goldman, Ran D

2012-08-01

Head lice infestations continue to be seen frequently in many communities. Some of these children require multiple treatments before eradication. What are the current treatment recommendations for head lice? Head lice (Pediculus humanus capitis) infestations are common, particularly among school-aged children. In order to minimize louse resistance, insecticide usage, and social stigmatization, diagnosis and treatment should be limited to those with live lice on the scalp. Options for management are predominantly topical therapies or physical removal. Large studies comparing the efficacy of these treatments are lacking. Treatment should be repeated in approximately 7 days if topical insecticides are used or every 2 to 3 days for 2 weeks if wet combing is used. Lice resistance patterns vary widely geographically, and resistance is now the most common cause of treatment failure.

Pediculosis and the pediatrician.

PubMed

Rasmussen, J E

1984-07-01

Head lice commonly evoke feelings of disgust, revulsion, anger, and shame among parents and patients. There should, however, be no great cause for such alarm if a physician suspects pediculosis capitis. The recent introduction of several new pediculicidal drugs now allows a choice among four distinct therapeutic agents, which should substantially improve control of isolated cases and epidemics. Physicians must be aware that consumer groups are pressing public health authorities and drug manufacturers to establish proper treatment standards and safety warnings for the use of these agents. In addition, some controversy surrounds the use of lindane in children. This paper reviews the epidemiology and clinical appearance of pediculosis capitis in children, with emphasis on these recent developments. Pubic lice (Phthirus pubis) and body lice (Pediculus humanus corporis), both of which are much less common pediatric infestations, are mentioned only briefly.

Contact and fumigant toxicity of hexane flower bud extract of Syzygium aromaticum and its compounds against Pediculus humanus capitis (Phthiraptera: Pediculidae).

PubMed

Bagavan, Asokan; Rahuman, Abdul Abdul; Kamaraj, Chinnaperumal; Elango, Gandhi; Zahir, Abdul Abduz; Jayaseelan, Chidambaram; Santhoshkumar, Thirunavukkarasu; Marimuthu, Sampath

2011-11-01

The head lice, Pediculus humanus capitis De Geer is an obligate ectoparasite of humans that causes pediculosis capitis, a nuisance for millions of people worldwide, with high prevalence in children. P. humanus capitis has been treated by methods that include the physical remotion of lice, various domestic treatments, and conventional insecticides. None of these methods render complete protection, and there is clear evidence for the evolution of resistance and cross-resistance to conventional insecticides. Non-toxic alternative options are hence needed for head lice treatment and/or prevention, and natural products from plants are good candidates for safer control agents that may provide good anti-lice activity. The plant extracts are good and safe alternatives due to their low toxicity to mammals and easy biodegradability. The present study carried out the pediculocidal activity using the hexane flower bud extract of Syzygium aromaticum (Myrtaceae) against P. humanus capitis examined by direct contact and fumigant toxicity (closed- and open-container methods) bioassay. The chemical composition of S. aromaticum flower bud hexane extract was analyzed by gas chromatography-mass spectrometry. The major chemical constituent (58.79%) of flower bud hexane extract S. aromaticum was identified as chavibetol (5-allyl-2-methoxyphenol) by comparison of mass spectral data and retention times. The hexane extract of S. aromaticum was subjected to gas chromatography analysis, and totally 47 compounds were detected, of which chavibetol was predominantly present. The other major constituents present in the hexane extract were eugenol acetate (phenol,2-methoxy-4-(2-propenyl)-,acetate (15.09%), caryophyllene-(I1) (2,6,10,10-tetramethyl bicyclo [7.2.0] undeca-1,6-diene (13.75%), caryophyllene oxide (3.04%), 2,6,6,9-tetramethyl-1,4,8-cycloundecatriene (1.67%), and copaene (1.33%). The filter paper contact bioassay study showed pronounced pediculicidal activity in the flower bud hexane extract of S. aromaticum. The toxic effect was determined for every five in an 80-min treatment. The result showed percent mortality of 40, 82, and 100 at 5, 10, and 20 min, and the median lethal time (LT(50)) value was 5.83 (0.5 mg/cm(2)); 28, 82, and 100 at 5, 10, and 30 min. (LT(50) = 6.54; 0.25 mg/cm(2)); and 13, 22, 42, 80, and 100 at 5, 10, 20, 40, and 80 min (LT(50) = 18.68; 0.125 mg/cm(2)), respectively. The vapor phase toxicity was tested at 0.25 mg/cm(2). There was a significant difference in pediculicidal activity of S. aromaticum extract against P. humanus capitis between closed- and open-container methods. Adult mortalities were determined for every five in 60 min (closed method) and for every ten in 180 min (open method). The closed method showed the percent mortality was 45, 88, and 100 at 5, 10, and 15 min (LT(50) = 5.39), respectively. In the open-container method, the percent mortality was observed 5, 20, 47, 84, and 100 at 10, 20, 60, 120, and 180 min (LT(50) = 47.91), respectively. The mortality was more effective in the closed containers than in open ones, indicating that the effect of hexane extract was largely a result of action in the vapor phase exhibited fumigant toxicity. Studies of anti-lice activity of extract provide the basis for preliminary conclusions of structure activity relationships; although no clear patterns can yet be drawn. We here attempt to provide a concise compilation of the available information on anti-lice activity of plant extracts and plant-derived compounds.

Pediculosis capitis: an update.

PubMed

Madke, Bhushan; Khopkar, Uday

2012-01-01

Head louse infestation, or pediculosis capitis, caused by Pediculus humanus var. capitis, is a common health concern in pediatric age group. An itching of the scalp is the chief symptom, whereas presence of viable nits confirms the diagnosis of head louse infestation. Secondary bacterial infection with impetignization with cervical and occipital lymphadenopathy can complicate the clinical scenario with physician misdiagnosing pediculosis to a primary bacterial infection. Screening and treatment of all close contacts is necessary for an adequate management of pediculosis. Medical management of head louse infestation requires proper application of topical pediculicidal agents', chiefly permethrin lotion and wet combing with a fine toothcomb. Severe cases with high parasitic load justify the use of either oral cotrimoxazole or Ivermectin. Other described technique involves a single application of hot air for 30 minutes. Radical but culturally unacceptable method would be shaving of scalp in resistant cases. Environmental fogging with insecticides is neither necessary nor recommended.

Drought and Epidemic Typhus, Central Mexico, 1655–1918

PubMed Central

Acuna-Soto, Rudofo; Stahle, David W.

2014-01-01

Epidemic typhus is an infectious disease caused by the bacterium Rickettsia prowazekii and transmitted by body lice (Pediculus humanus corporis). This disease occurs where conditions are crowded and unsanitary. This disease accompanied war, famine, and poverty for centuries. Historical and proxy climate data indicate that drought was a major factor in the development of typhus epidemics in Mexico during 1655–1918. Evidence was found for 22 large typhus epidemics in central Mexico, and tree-ring chronologies were used to reconstruct moisture levels over central Mexico for the past 500 years. Below-average tree growth, reconstructed drought, and low crop yields occurred during 19 of these 22 typhus epidemics. Historical documents describe how drought created large numbers of environmental refugees that fled the famine-stricken countryside for food relief in towns. These refugees often ended up in improvised shelters in which crowding encouraged conditions necessary for spread of typhus. PMID:24564928

[Cockroaches and co. The role of health pests as allergen source].

PubMed

Raulf, M; Sander, I; Gonnissen, D; Zahradnik, E; Brüning, T

2014-05-01

In most of the cases health pests are carriers of pathogens or parasites which have a negative impact on human health or affect the health of other mammals. What is lesser known is that they can also act as allergens. Most of the health pests in this sense belong to the arthropods, such as cockroaches (Blattaria), mosquitos (Culiciformia), lice (Pediculus humanus corporis), fleas (Siphonaptera) and ticks (Argasidae). In the group of vertebrates rats (Rattus norvegicus and Rattus rattus), house mice (Mus musculus) and pigeons (Columba livia domestica) are also classified as health pests. Also storage pests which are not carriers of pathogens can induce secondary infestation with hygiene pests or molds and have an underestimated impact on human health. In this article selected examples of health pests and also storage pests as an allergen source are described, taking into account the sensitization prevalence and identified single allergens.

Drought and epidemic typhus, central Mexico, 1655-1918.

PubMed

Burns, Jordan N; Acuna-Soto, Rudofo; Stahle, David W

2014-03-01

Epidemic typhus is an infectious disease caused by the bacterium Rickettsia prowazekii and transmitted by body lice (Pediculus humanus corporis). This disease occurs where conditions are crowded and unsanitary. This disease accompanied war, famine, and poverty for centuries. Historical and proxy climate data indicate that drought was a major factor in the development of typhus epidemics in Mexico during 1655-1918. Evidence was found for 22 large typhus epidemics in central Mexico, and tree-ring chronologies were used to reconstruct moisture levels over central Mexico for the past 500 years. Below-average tree growth, reconstructed drought, and low crop yields occurred during 19 of these 22 typhus epidemics. Historical documents describe how drought created large numbers of environmental refugees that fled the famine-stricken countryside for food relief in towns. These refugees often ended up in improvised shelters in which crowding encouraged conditions necessary for spread of typhus.

Solving a Bloody Mess: B-Vitamin Independent Metabolic Convergence among Gammaproteobacterial Obligate Endosymbionts from Blood-Feeding Arthropods and the Leech Haementeria officinalis

PubMed Central

Manzano-Marín, Alejandro; Oceguera-Figueroa, Alejandro; Latorre, Amparo; Jiménez-García, Luis F.; Moya, Andres

2015-01-01

Endosymbiosis is a common phenomenon in nature, especially between bacteria and insects, whose typically unbalanced diets are usually complemented by their obligate endosymbionts. While much interest and focus has been directed toward phloem-feeders like aphids and mealybugs, blood-feeders such as the Lone star tick (Amblyomma americanum), Glossina flies, and the human body louse (Pediculus humanus corporis) depend on obligate endosymbionts which complement their B-vitamin-deficient diets, and thus are required for growth and survival. Glossiphoniid leeches have also been found to harbor distinct endosymbionts housed in specialized organs. Here, we present the genome of the bacterial endosymbiont from Haementeria officinalis, first of a glossiphoniid leech. This as-yet-unnamed endosymbiont belongs to the Gammaproteobacteria, has a pleomorphic shape and is restricted to bacteriocytes. For this bacterial endosymbiont, we propose the name Candidatus Providencia siddallii. This symbiont possesses a highly reduced genome with high A+T content and a reduced set of metabolic capabilities, all of which are common characteristics of ancient obligate endosymbionts of arthropods. Its genome has retained many pathways related to the biosynthesis of B-vitamins, pointing toward a role in supplementing the blood-restricted diet of its host. Through comparative genomics against the endosymbionts of A. americanum, Glossina flies, and P. humanus corporis, we were able to detect a high degree of metabolic convergence among these four very distantly related endosymbiotic bacteria. PMID:26454017

Decoding the Ubiquitin-Mediated Pathway of Arthropod Disease Vectors

PubMed Central

Choy, Anthony; Severo, Maiara S.; Sun, Ruobai; Girke, Thomas; Gillespie, Joseph J.; Pedra, Joao H. F.

2013-01-01

Protein regulation by ubiquitin has been extensively described in model organisms. However, characterization of the ubiquitin machinery in disease vectors remains mostly unknown. This fundamental gap in knowledge presents a concern because new therapeutics are needed to control vector-borne diseases, and targeting the ubiquitin machinery as a means for disease intervention has been already adopted in the clinic. In this study, we employed a bioinformatics approach to uncover the ubiquitin-mediated pathway in the genomes of Anopheles gambiae, Aedes aegypti, Culex quinquefasciatus, Ixodes scapularis, Pediculus humanus and Rhodnius prolixus. We observed that (1) disease vectors encode a lower percentage of ubiquitin-related genes when compared to Drosophila melanogaster, Mus musculus and Homo sapiens but not Saccharomyces cerevisiae; (2) overall, there are more proteins categorized as E3 ubiquitin ligases when compared to E2-conjugating or E1-activating enzymes; (3) the ubiquitin machinery within the three mosquito genomes is highly similar; (4) ubiquitin genes are more than doubled in the Chagas disease vector (R. prolixus) when compared to other arthropod vectors; (5) the deer tick I. scapularis and the body louse (P. humanus) genomes carry low numbers of E1-activating enzymes and HECT-type E3 ubiquitin ligases; (6) R. prolixus have low numbers of RING-type E3 ubiquitin ligases; and (7) C. quinquefasciatus present elevated numbers of predicted F-box E3 ubiquitin ligases, JAB and UCH deubiquitinases. Taken together, these findings provide novel opportunities to study the interaction between a pathogen and an arthropod vector. PMID:24205097

Heteroplasmy in the Mitochondrial Genomes of Human Lice and Ticks Revealed by High Throughput Sequencing

PubMed Central

Xiong, Haoyu; Barker, Stephen C.; Burger, Thomas D.; Raoult, Didier; Shao, Renfu

2013-01-01

The typical mitochondrial (mt) genomes of bilateral animals consist of 37 genes on a single circular chromosome. The mt genomes of the human body louse, Pediculus humanus, and the human head louse, Pediculus capitis, however, are extensively fragmented and contain 20 minichromosomes, with one to three genes on each minichromosome. Heteroplasmy, i.e. nucleotide polymorphisms in the mt genome within individuals, has been shown to be significantly higher in the mt cox1 gene of human lice than in humans and other animals that have the typical mt genomes. To understand whether the extent of heteroplasmy in human lice is associated with mt genome fragmentation, we sequenced the entire coding regions of all of the mt minichromosomes of six human body lice and six human head lice from Ethiopia, China and France with an Illumina HiSeq platform. For comparison, we also sequenced the entire coding regions of the mt genomes of seven species of ticks, which have the typical mitochondrial genome organization of bilateral animals. We found that the level of heteroplasmy varies significantly both among the human lice and among the ticks. The human lice from Ethiopia have significantly higher level of heteroplasmy than those from China and France (Pt<0.05). The tick, Amblyomma cajennense, has significantly higher level of heteroplasmy than other ticks (Pt<0.05). Our results indicate that heteroplasmy level can be substantially variable within a species and among closely related species, and does not appear to be determined by single factors such as genome fragmentation. PMID:24058467

Heteroplasmy in the mitochondrial genomes of human lice and ticks revealed by high throughput sequencing.

PubMed

Xiong, Haoyu; Barker, Stephen C; Burger, Thomas D; Raoult, Didier; Shao, Renfu

2013-01-01

The typical mitochondrial (mt) genomes of bilateral animals consist of 37 genes on a single circular chromosome. The mt genomes of the human body louse, Pediculus humanus, and the human head louse, Pediculus capitis, however, are extensively fragmented and contain 20 minichromosomes, with one to three genes on each minichromosome. Heteroplasmy, i.e. nucleotide polymorphisms in the mt genome within individuals, has been shown to be significantly higher in the mt cox1 gene of human lice than in humans and other animals that have the typical mt genomes. To understand whether the extent of heteroplasmy in human lice is associated with mt genome fragmentation, we sequenced the entire coding regions of all of the mt minichromosomes of six human body lice and six human head lice from Ethiopia, China and France with an Illumina HiSeq platform. For comparison, we also sequenced the entire coding regions of the mt genomes of seven species of ticks, which have the typical mitochondrial genome organization of bilateral animals. We found that the level of heteroplasmy varies significantly both among the human lice and among the ticks. The human lice from Ethiopia have significantly higher level of heteroplasmy than those from China and France (Pt<0.05). The tick, Amblyomma cajennense, has significantly higher level of heteroplasmy than other ticks (Pt<0.05). Our results indicate that heteroplasmy level can be substantially variable within a species and among closely related species, and does not appear to be determined by single factors such as genome fragmentation.

Structure of PINK1 in complex with its substrate ubiquitin

PubMed Central

Schubert, Alexander F.; Gladkova, Christina; Pardon, Els; Wagstaff, Jane L.; Freund, Stefan M.V.; Steyaert, Jan; Maslen, Sarah L.; Komander, David

2018-01-01

Autosomal recessive juvenile Parkinsonism (AR-JP) is caused by mutations in a number of PARK genes, in particular in the E3 ubiquitin ligase Parkin (PARK2), and in its upstream protein kinase PINK1 (PARK6). PINK1 phosphorylates ubiquitin and the Parkin ubiquitin-like domain on structurally protected Ser65 to trigger mitophagy. We here report a crystal structure of a nanobody stabilised complex between Pediculus humanus corporis (Ph)PINK1 bound to ubiquitin in the ‘C-terminally retracted’ (Ub-CR) conformation. The structure reveals many peculiarities of PINK1, including the architecture of the C-terminal region, and reveals how the PINK1 N-lobe binds ubiquitin via a unique insertion. The flexible Ser65-loop in the Ub-CR conformation reaches the activation segment, facilitating placement of Ser65 in a phosphate accepting position. The structure also explains how autophosphorylation in the N-lobe stabilises structurally and functionally important insertions, and reveals the molecular basis for AR-JP causing mutations, some of which disrupt ubiquitin binding. PMID:29160309

Ivermectin lipid-based nanocarriers as novel formulations against head lice.

PubMed

Ullio-Gamboa, Gabriela; Palma, Santiago; Benoit, Jean Pierre; Allemandi, Daniel; Picollo, María Inés; Toloza, Ariel Ceferino

2017-08-01

The use of pyrethroids to control the human head louse, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), has suffered considerable loss of efficacy due to the evolution of resistance. Thus, the development of efficiently insecticide delivery systems is imperative for the control of head lice. We studied the insecticidal activity of ivermectin-loaded lipid nanocapsules (IVM-LNC) against permethrin-resistant head lice from Argentina. The LNC, prepared by a phase inversion procedure, were characterized in terms of size, surface potential, and physical stability. These nanoparticles were nearly spherical with mean diameters of 55 nm and narrow size distribution (PI ≤ 0.2). The KT 50 mortality values of head lice after exposure to two IVM-LNC formulations (0.11 and 0.28%) were significantly smaller (5 and 3 h, respectively) compared to those exposed only to LNC control group (8 h). This investigation showed the effectiveness in the encapsulation of ivermectin (IVM) into stable LNC dispersion with a potential clinical activity against head lice.

Epidemic typhus.

PubMed

Bechah, Yassina; Capo, Christian; Mege, Jean-Louis; Raoult, Didier

2008-07-01

Epidemic typhus is transmitted to human beings by the body louse Pediculus humanus corporis. The disease is still considered a major threat by public-health authorities, despite the efficacy of antibiotics, because poor sanitary conditions are conducive to louse proliferation. Until recently, Rickettsia prowazekii, the causal agent, was thought to be confined to human beings and their body lice. Since 1975, R prowazekii infection in human beings has been related to contact with the flying squirrel Glaucomys volans in the USA. Moreover, Brill-Zinsser disease, a relapsed form of epidemic typhus that appears as sporadic cases many years after the initial infection, is unrelated to louse infestation. Stress or a waning immune system are likely to reactivate this earlier persistent infection, which could be the source of new epidemics when conditions facilitate louse infestation. Finally, R prowazekii is a potential category B bioterrorism agent, because it is stable in dried louse faeces and can be transmitted through aerosols. An increased understanding of the pathogenesis of epidemic typhus may be useful for protection against this bacterial threat.

Evidence that clade A and clade B head lice live in sympatry and recombine in Algeria.

PubMed

Boutellis, A; Bitam, I; Fekir, K; Mana, N; Raoult, D

2015-03-01

Pediculus humanus L. (Psocodea: Pediculidae) can be characterized into three deeply divergent lineages (clades) based on mitochondrial DNA. Clade A consists of both head lice and clothing lice and is distributed worldwide. Clade B consists of head lice only and is mainly found in North and Central America, and in western Europe and Australia. Clade C, which consists only of head lice, is found in Ethiopia, Nepal and Senegal. Twenty-six head lice collected from pupils at different elementary schools in two localities in Algiers (Algeria) were analysed using molecular methods for genotyping lice (cytochrome b and the multi-spacer typing (MST) method. For the first time, we found clade B head lice in Africa living in sympatry with clade A head lice. The phylogenetic analysis of the concatenated sequences of these populations of head lice showed that clade A and clade B head lice had recombined, suggesting that interbreeding occurs when lice live in sympatry. © 2014 The Royal Entomological Society.

Solving a Bloody Mess: B-Vitamin Independent Metabolic Convergence among Gammaproteobacterial Obligate Endosymbionts from Blood-Feeding Arthropods and the Leech Haementeria officinalis.

PubMed

Manzano-Marín, Alejandro; Oceguera-Figueroa, Alejandro; Latorre, Amparo; Jiménez-García, Luis F; Moya, Andres

2015-10-09

Endosymbiosis is a common phenomenon in nature, especially between bacteria and insects, whose typically unbalanced diets are usually complemented by their obligate endosymbionts. While much interest and focus has been directed toward phloem-feeders like aphids and mealybugs, blood-feeders such as the Lone star tick (Amblyomma americanum), Glossina flies, and the human body louse (Pediculus humanus corporis) depend on obligate endosymbionts which complement their B-vitamin-deficient diets, and thus are required for growth and survival. Glossiphoniid leeches have also been found to harbor distinct endosymbionts housed in specialized organs. Here, we present the genome of the bacterial endosymbiont from Haementeria officinalis, first of a glossiphoniid leech. This as-yet-unnamed endosymbiont belongs to the Gammaproteobacteria, has a pleomorphic shape and is restricted to bacteriocytes. For this bacterial endosymbiont, we propose the name Candidatus Providencia siddallii. This symbiont possesses a highly reduced genome with high A+T content and a reduced set of metabolic capabilities, all of which are common characteristics of ancient obligate endosymbionts of arthropods. Its genome has retained many pathways related to the biosynthesis of B-vitamins, pointing toward a role in supplementing the blood-restricted diet of its host. Through comparative genomics against the endosymbionts of A. americanum, Glossina flies, and P. humanus corporis, we were able to detect a high degree of metabolic convergence among these four very distantly related endosymbiotic bacteria. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Genome sequences of the human body louse and its primary endosymbiont provide insights into the permanent parasitic lifestyle.

PubMed

Kirkness, Ewen F; Haas, Brian J; Sun, Weilin; Braig, Henk R; Perotti, M Alejandra; Clark, John M; Lee, Si Hyeock; Robertson, Hugh M; Kennedy, Ryan C; Elhaik, Eran; Gerlach, Daniel; Kriventseva, Evgenia V; Elsik, Christine G; Graur, Dan; Hill, Catherine A; Veenstra, Jan A; Walenz, Brian; Tubío, José Manuel C; Ribeiro, José M C; Rozas, Julio; Johnston, J Spencer; Reese, Justin T; Popadic, Aleksandar; Tojo, Marta; Raoult, Didier; Reed, David L; Tomoyasu, Yoshinori; Kraus, Emily; Krause, Emily; Mittapalli, Omprakash; Margam, Venu M; Li, Hong-Mei; Meyer, Jason M; Johnson, Reed M; Romero-Severson, Jeanne; Vanzee, Janice Pagel; Alvarez-Ponce, David; Vieira, Filipe G; Aguadé, Montserrat; Guirao-Rico, Sara; Anzola, Juan M; Yoon, Kyong S; Strycharz, Joseph P; Unger, Maria F; Christley, Scott; Lobo, Neil F; Seufferheld, Manfredo J; Wang, Naikuan; Dasch, Gregory A; Struchiner, Claudio J; Madey, Greg; Hannick, Linda I; Bidwell, Shelby; Joardar, Vinita; Caler, Elisabet; Shao, Renfu; Barker, Stephen C; Cameron, Stephen; Bruggner, Robert V; Regier, Allison; Johnson, Justin; Viswanathan, Lakshmi; Utterback, Terry R; Sutton, Granger G; Lawson, Daniel; Waterhouse, Robert M; Venter, J Craig; Strausberg, Robert L; Berenbaum, May R; Collins, Frank H; Zdobnov, Evgeny M; Pittendrigh, Barry R

2010-07-06

As an obligatory parasite of humans, the body louse (Pediculus humanus humanus) is an important vector for human diseases, including epidemic typhus, relapsing fever, and trench fever. Here, we present genome sequences of the body louse and its primary bacterial endosymbiont Candidatus Riesia pediculicola. The body louse has the smallest known insect genome, spanning 108 Mb. Despite its status as an obligate parasite, it retains a remarkably complete basal insect repertoire of 10,773 protein-coding genes and 57 microRNAs. Representing hemimetabolous insects, the genome of the body louse thus provides a reference for studies of holometabolous insects. Compared with other insect genomes, the body louse genome contains significantly fewer genes associated with environmental sensing and response, including odorant and gustatory receptors and detoxifying enzymes. The unique architecture of the 18 minicircular mitochondrial chromosomes of the body louse may be linked to the loss of the gene encoding the mitochondrial single-stranded DNA binding protein. The genome of the obligatory louse endosymbiont Candidatus Riesia pediculicola encodes less than 600 genes on a short, linear chromosome and a circular plasmid. The plasmid harbors a unique arrangement of genes required for the synthesis of pantothenate, an essential vitamin deficient in the louse diet. The human body louse, its primary endosymbiont, and the bacterial pathogens that it vectors all possess genomes reduced in size compared with their free-living close relatives. Thus, the body louse genome project offers unique information and tools to use in advancing understanding of coevolution among vectors, symbionts, and pathogens.

Genome sequences of the human body louse and its primary endosymbiont provide insights into the permanent parasitic lifestyle

PubMed Central

Kirkness, Ewen F.; Haas, Brian J.; Sun, Weilin; Braig, Henk R.; Perotti, M. Alejandra; Clark, John M.; Lee, Si Hyeock; Robertson, Hugh M.; Kennedy, Ryan C.; Elhaik, Eran; Gerlach, Daniel; Kriventseva, Evgenia V.; Elsik, Christine G.; Graur, Dan; Hill, Catherine A.; Veenstra, Jan A.; Walenz, Brian; Tubío, José Manuel C.; Ribeiro, José M. C.; Rozas, Julio; Johnston, J. Spencer; Reese, Justin T.; Popadic, Aleksandar; Tojo, Marta; Raoult, Didier; Reed, David L.; Tomoyasu, Yoshinori; Kraus, Emily; Mittapalli, Omprakash; Margam, Venu M.; Li, Hong-Mei; Meyer, Jason M.; Johnson, Reed M.; Romero-Severson, Jeanne; VanZee, Janice Pagel; Alvarez-Ponce, David; Vieira, Filipe G.; Aguadé, Montserrat; Guirao-Rico, Sara; Anzola, Juan M.; Yoon, Kyong S.; Strycharz, Joseph P.; Unger, Maria F.; Christley, Scott; Lobo, Neil F.; Seufferheld, Manfredo J.; Wang, NaiKuan; Dasch, Gregory A.; Struchiner, Claudio J.; Madey, Greg; Hannick, Linda I.; Bidwell, Shelby; Joardar, Vinita; Caler, Elisabet; Shao, Renfu; Barker, Stephen C.; Cameron, Stephen; Bruggner, Robert V.; Regier, Allison; Johnson, Justin; Viswanathan, Lakshmi; Utterback, Terry R.; Sutton, Granger G.; Lawson, Daniel; Waterhouse, Robert M.; Venter, J. Craig; Strausberg, Robert L.; Collins, Frank H.; Zdobnov, Evgeny M.; Pittendrigh, Barry R.

2010-01-01

As an obligatory parasite of humans, the body louse (Pediculus humanus humanus) is an important vector for human diseases, including epidemic typhus, relapsing fever, and trench fever. Here, we present genome sequences of the body louse and its primary bacterial endosymbiont Candidatus Riesia pediculicola. The body louse has the smallest known insect genome, spanning 108 Mb. Despite its status as an obligate parasite, it retains a remarkably complete basal insect repertoire of 10,773 protein-coding genes and 57 microRNAs. Representing hemimetabolous insects, the genome of the body louse thus provides a reference for studies of holometabolous insects. Compared with other insect genomes, the body louse genome contains significantly fewer genes associated with environmental sensing and response, including odorant and gustatory receptors and detoxifying enzymes. The unique architecture of the 18 minicircular mitochondrial chromosomes of the body louse may be linked to the loss of the gene encoding the mitochondrial single-stranded DNA binding protein. The genome of the obligatory louse endosymbiont Candidatus Riesia pediculicola encodes less than 600 genes on a short, linear chromosome and a circular plasmid. The plasmid harbors a unique arrangement of genes required for the synthesis of pantothenate, an essential vitamin deficient in the louse diet. The human body louse, its primary endosymbiont, and the bacterial pathogens that it vectors all possess genomes reduced in size compared with their free-living close relatives. Thus, the body louse genome project offers unique information and tools to use in advancing understanding of coevolution among vectors, symbionts, and pathogens. PMID:20566863

Detoxification of ivermectin by ATP binding cassette transporter C4 and cytochrome P450 monooxygenase 6CJ1 in the human body louse, Pediculus humanus humanus.

PubMed

Kim, J H; Gellatly, K J; Lueke, B; Kohler, M; Nauen, R; Murenzi, E; Yoon, K S; Clark, J M

2018-02-01

We previously observed that ivermectin-induced detoxification genes, including ATP binding cassette transporter C4 (PhABCC4) and cytochrome P450 6CJ1 (CYP6CJ1) were identified from body lice following a brief exposure to a sublethal dose of ivermectin using a non-invasive induction assay. In this current study, the functional properties of PhABCC4 and CYP6CJ1 were investigated after expression in either X. laevis oocytes or using a baculovirus expression system, respectively. Efflux of [ 3 H]-9-(2-phosphonomethoxyethyl) adenine ([ 3 H]-PMEA), a known ABCC4 substrate in humans, was detected from PhABCC4 cRNA-injected oocytes by liquid scintillation spectrophotometric analysis and PhABCC4 expression in oocytes was confirmed using ABC transporter inhibitors. Efflux was also determined to be ATP-dependent. Using a variety of insecticides in a competition assay, only co-injection of ivermectin and dichlorodiphenyltrichloroethane led to decreased efflux of [ 3 H]-PMEA. PhABCC4-expressing oocytes also directly effluxed [ 3 H]-ivermectin, which increased over time. In addition, ivermectin appeared to be oxidatively metabolized and/or sequestered, although at low levels, following functional expression of CYP6CJ1 along with cytochrome P450 reductase in Sf9 cells. Our study suggests that PhABCC4 and perhaps CYP6CJ1 are involved in the Phase III and Phase I xenobiotic metabolism of ivermectin, respectively, and may play an important role in the evolution of ivermectin resistance in lice and other insects as field selection occurs. © 2017 The Royal Entomological Society.

Variable microsatellite loci for population genetic analysis of Old World monkey lice (Pedicinus sp.).

PubMed

Scholl, Katlyn; Allen, Julie M; Leendertz, Fabian H; Chapman, Colin A; Reed, David L

2012-10-01

Parasitic lice have been valuable informants of their host's evolutionary history because they complete their entire life cycle on the host and move between hosts primarily through direct host-to-host contact. Therefore, lice are confined to their hosts both in ecological and evolutionary time. Lice on great apes have been studied to examine details of their host's evolutionary history; however, species of Pedicinus, which parasitize the Old World monkeys, are less well known. We sampled lice from 2 groups of red colobus (Procolobus spp.) in Kibale National Park in Uganda and from red colobus and black and white colobus (Procolobus polycomos) in Taï National Park in Côte d'Ivoire. We used next-generation sequencing data analysis and the human body louse (Pediculus humanus humanus) genome to search for microsatellites for population genetic studies of Pedicinus lice. The 96 primer sets for microsatellite loci designed from the human body louse genome failed to amplify microsatellites in Pedicinus sp., perhaps due to the fast rate of evolution in parasitic lice. Of 63 microsatellites identified by next-generation sequencing data analysis of Pedicinus sp., 12 were variable among populations and 9 were variable within a single population. Our results suggest that these loci will be useful across the genus Pedicinus. We found that the lice in Uganda are not structured according to their hosts' social group; rather, 2 non-interbreeding populations of lice were found on both groups of red colobus. Because direct host-to-host contact is usually required for lice to move among hosts, these lice could be useful for identification and study of behavioral interactions between primate species.

Identification and screening of potent antimicrobial peptides in arthropod genomes.

PubMed

Duwadi, Deepesh; Shrestha, Anishma; Yilma, Binyam; Kozlovski, Itamar; Sa-Eed, Munaya; Dahal, Nikesh; Jukosky, James

2018-05-01

Using tBLASTn and BLASTp searches, we queried recently sequenced arthropod genomes and expressed sequence tags (ESTs) using a database of known arthropod cecropins, defensins, and attacins. We identified and synthesized 6 potential AMPs and screened them for antimicrobial activity. Using radial diffusion assays and microtiter antimicrobial assays, we assessed the in vitro antimicrobial effects of these peptides against several human pathogens including Gram-positive and Gram-negative bacteria and fungi. We also conducted hemolysis assays to examine the cytotoxicity of these peptides to mammalian cells. Four of the six peptides identified showed antimicrobial effects in these assays. We also created truncated versions of these four peptides to assay their antimicrobial activity. Two cecropins derived from the monarch butterfly genome (Danaus plexippus), DAN1 and DAN2, showed minimum inhibitory concentrations (MICs) in the range of 2-16 μg/ml when screened against Gram-negative bacteria. HOLO1 and LOUDEF1, two defensin-like peptides derived from red flour beetle (Tribolium castaneum) and human body louse (Pediculus humanus humanus), respectively, exhibited MICs in the range of 13-25 μg/ml against Gram-positive bacteria. Furthermore, HOLO1 showed an MIC less than 5 μg/ml against the fungal species Candida albicans. These peptides exhibited no hemolytic activity at concentrations up to 200 μg/ml. The truncated peptides derived from DAN2 and HOLO1 showed very little antimicrobial activity. Our experiments show that the peptides DAN1, DAN2, HOLO1, and LOUDEF1 showed potent antimicrobial activity in vitro against common human pathogens, did not lyse mammalian red blood cells, and indicates their potential as templates for novel therapeutic agents against microbial infection. Copyright © 2018 Elsevier Inc. All rights reserved.

[Epidemic typhus in Africa].

PubMed

Ndihokubwayo, J B; Raoult, D

1999-01-01

Epidemic typhus is caused by a small strictly intracellular virus named Rickettsia prowazekii, a member of the Rickettsial family. It is transmitted to man by the body louse, Pediculus humanus. Although now rare in Western countries, exanthematic typhus remains common in the Southern hemisphere due to poverty, inadequate clothing hygiene, and poor socioeconomic conditions. In Africa, outbreaks have historically occurred in Burundi, Rwanda, southwest Ouganda, and Ethiopia. The largest outbreak of epidemic typhus since the World War II was reported in Burundi where ongoing civil war since October 1993 has forced 10 p. 100 of the population of Burundi to live in cold, promiscuity, and malnutrition of makeshift refugee camps. The purpose of this report based on our two-year experience working with this unfortunate population is to describe the characteristics of this disease in Africa where the epidemic form had become rare until recently. Indeed political unrest as well as numerous civil wars are now epidmiological factors favorizing outbreaks of epidemic typhus at any time. This overview also provides an opportunity to recall epidemiological, bacteriological, and clinical aspects of typhus as well as diagnosis and treatment of the disease in the context of Africa.

Transcriptome identification of putative genes involved in protein catabolism and innate immune response in human body louse (Pediculicidae: Pediculus humanus).

PubMed

Pedra, Joao H F; Brandt, Amanda; Li, Hong-Mei; Westerman, Rick; Romero-Severson, Jeanne; Pollack, Richard J; Murdock, Larry L; Pittendrigh, Barry R

2003-11-01

Genomics information relating to human body lice is surprisingly scarce, and this has constrained studies of their physiology, immunology and vector biology. To identify novel body louse genes, we used engorged adult lice to generate a cDNA library. Initially, 1152 clones were screened for inserts, edited for removal of vector sequences and base pairs of poor quality, and viewed for splicing variations, gene families and polymorphism. Computational methods identified 506 inferred open reading frames including the first predicted louse defensin. The inferred defensin aligns well with other insect defensins and has highly conserved cysteine residues, as are known for other defensin sequences. Two cysteine and five serine proteinases were categorized according to their inferred catalytic sites. We also discovered seven putative ubiquitin-pathway genes and four iron metabolizing deduced enzymes. Finally, glutathione-S-transferases and cytochrome P450 genes were among the detoxification enzymes found. Results from this first systematic effort to discover human body louse genes should promote further studies in Phthiraptera and lice.

Structure of PINK1 in complex with its substrate ubiquitin.

PubMed

Schubert, Alexander F; Gladkova, Christina; Pardon, Els; Wagstaff, Jane L; Freund, Stefan M V; Steyaert, Jan; Maslen, Sarah L; Komander, David

2017-12-07

Autosomal-recessive juvenile Parkinsonism (AR-JP) is caused by mutations in a number of PARK genes, in particular the genes encoding the E3 ubiquitin ligase Parkin (PARK2, also known as PRKN) and its upstream protein kinase PINK1 (also known as PARK6). PINK1 phosphorylates both ubiquitin and the ubiquitin-like domain of Parkin on structurally protected Ser65 residues, triggering mitophagy. Here we report a crystal structure of a nanobody-stabilized complex containing Pediculus humanus corporis (Ph)PINK1 bound to ubiquitin in the 'C-terminally retracted' (Ub-CR) conformation. The structure reveals many peculiarities of PINK1, including the architecture of the C-terminal region, and reveals how the N lobe of PINK1 binds ubiquitin via a unique insertion. The flexible Ser65 loop in the Ub-CR conformation contacts the activation segment, facilitating placement of Ser65 in a phosphate-accepting position. The structure also explains how autophosphorylation in the N lobe stabilizes structurally and functionally important insertions, and reveals the molecular basis of AR-JP-causing mutations, some of which disrupt ubiquitin binding.

A preliminary pilot survey on head lice, pediculosis in Sharkia Governorate and treatment of lice with natural plant extracts.

PubMed

El-Basheir, Zeinab M; Fouad, Mahmoud A H

2002-12-01

Twelve different representative areas in Sharkia Governorate were surveyed for head lice, Pediculus humanus capitis. The pre-valence was investigated among 120 houses containing 2,448 individual, with different age, sex and socioeconomic status. Examination was done by naked eye aided with hand-lens. A total of 137 individuals were infested. Infestation rates were higher in the rural areas with low socioeconomic levels, concrete houses with over-crowded family members. Children had significantly higher infestation rates than adults. Males had lower infestation rates than females. However, the hair length and permanent hair washing were the factors accounted for both age and sex difference in prevalence of pediculosis. Head lice infestations were found all over the year, but increased in summer and spring. One hundred infested patients (90 females and 10 males) with different aged and hair length were treated with tour mixed cream from plants Lawsonia alba L. (Henna). Trigonella faemum-gracanum (Fenugreek), Hibiscus cannabinus (Hibiscus) and Artemisia cina (Wormseed). The head lice completely disappeared within a week among those patients treated by henna mixed with aqueous extract of sheah (100%) or mixed with helba (75%) or with karkada (50%).

Pediculosis capitis: new insights into epidemiology, diagnosis and treatment.

PubMed

Feldmeier, H

2012-09-01

Pediculosis capitis is a ubiquitous parasitic skin disease caused by Pediculus humanus capitis. Head lice are highly specialised parasites which can propagate only on human scalp and hair. Transmission occurs by direct head-to-head contact. Head lice are vectors of important bacterial pathogens. Pediculosis capitis usually occurs in small epidemics in play groups, kindergartens and schools. Population-based studies in European countries show highly diverging prevalences, ranging from 1% to 20%. The diagnosis of head lice infestation is made through the visual inspection of hair and scalp or dry/wet combing. The optimal method for the diagnosis of active head lice infestation is dry/wet combing. Topical application of a pediculicide is the most common treatment. Compounds with a neurotoxic mode of action are widely used but are becoming less effective due to resistant parasite populations. Besides, their use is restricted by safety concerns. Dimeticones, silicone oils with a low surface tension and the propensity to perfectly coat surfaces, have a purely physical mode of action. This group of compounds is highly effective and safe, and there is no risk that head lice become resistant. The control of epidemics requires active contact tracing and synchronised treatment with an effective and safe pediculicide.

Differential gene expression in laboratory strains of human head and body lice when challenged with Bartonella quintana, a pathogenic bacterium

PubMed Central

Previte, D.; Olds, B. P.; Yoon, K.; Sun, W.; Muir, W.; Paige, K. N.; Lee, S. H.; Clark, J.; Koehler, J. E.; Pittendrigh, B. R.

2014-01-01

Human head and body lice are obligatory hematophagous ectoparasites that belong to a single species, Pediculus humanus. Only body lice, however, are vectors of the infectious Gram-negative bacterium Bartonella quintana. Because of their near identical genomes, yet differential vector competence, head and body lice provide a unique model system to study the gain or loss of vector competence. Using our in vitro louse-rearing system, we infected head and body lice with blood containing B. quintana in order to detect both differences in the proliferation of B. quintana and transcriptional differences of immune-related genes in the lice. B. quintana proliferated rapidly in body lice at 6 days postinfection, but plateaued in head lice at 4 days postinfection. RNAseq and quantitative real-time PCR validation analyses determined gene expression differences. Eight immunoresponse genes were observed to be significantly different with many associated with the Toll pathway: Fibrinogen-like protein, Spaetzle, Defensin 1, Serpin, Scavenger receptor A and Apolipoporhrin 2. Our findings support the hypothesis that body lice, unlike head lice, fight infection from B. quintana only at the later stages of its proliferation. PMID:24404961

Of Lice and Math: Using Models to Understand and Control Populations of Head Lice

PubMed Central

Laguna, Mara Fabiana; Risau-Gusman, Sebastián

2011-01-01

In this paper we use detailed data about the biology of the head louse (pediculus humanus capitis) to build a model of the evolution of head lice colonies. Using theory and computer simulations, we show that the model can be used to assess the impact of the various strategies usually applied to eradicate head lice, both conscious (treatments) and unconscious (grooming). In the case of treatments, we study the difference in performance that arises when they are applied in systematic and non-systematic ways. Using some reasonable simplifying assumptions (as random mixing of human groups and the same mobility for all life stages of head lice other than eggs) we model the contagion of pediculosis using only one additional parameter. It is shown that this parameter can be tuned to obtain collective infestations whose characteristics are compatible with what is given in the literature on real infestations. We analyze two scenarios: One where group members begin treatment when a similar number of lice are present in each head, and another where there is one individual who starts treatment with a much larger threshold (“superspreader”). For both cases we assess the impact of several collective strategies of treatment. PMID:21799752

Louse- and flea-borne rickettsioses: biological and genomic analyses

PubMed Central

Gillespie, Joseph J.; Ammerman, Nicole C.; Beier-Sexton, Magda; Sobral, Bruno S.; Azad, Abdu F.

2009-01-01

In contrast to 15 or more validated and/or proposed tick-borne spotted fever group species, only three named medically important rickettsial species are associated with insects. These insect-borne rickettsiae are comprised of two highly pathogenic species, Rickettsia prowazekii (the agent of epidemic typhus) and R. typhi (the agent of murine typhus), as well as R. felis, a species with unconfirmed pathogenicity. Rickettsial association with obligate hematophagous insects such as the human body louse (R. prowazekii transmitted by Pediculus h. humanus) and several flea species (R. typhi and R. felis, as well as R. prowazekii in sylvatic form) provides rickettsiae the potential for further multiplications, longer transmission cycles and rapid spread among susceptible human populations. Both human body lice and fleas are intermittent feeders capable of multiple blood meals per generation, facilitating the efficient transmission of rickettsiae to several disparate hosts within urban/rural ecosystems. While taking into consideration the existing knowledge of rickettsial biology and genomic attributes, we have analyzed and summarized the interacting features that are unique to both the rickettsiae and their vector fleas and lice. Furthermore, factors that underlie rickettsial changing ecology, where native mammalian populations are involved in the maintenance of rickettsial cycle and transmission, are discussed. PMID:19036234

Differential gene expression in laboratory strains of human head and body lice when challenged with Bartonella quintana, a pathogenic bacterium.

PubMed

Previte, D; Olds, B P; Yoon, K; Sun, W; Muir, W; Paige, K N; Lee, S H; Clark, J; Koehler, J E; Pittendrigh, B R

2014-04-01

Human head and body lice are obligatory hematophagous ectoparasites that belong to a single species, Pediculus humanus. Only body lice, however, are vectors of the infectious Gram-negative bacterium Bartonella quintana. Because of their near identical genomes, yet differential vector competence, head and body lice provide a unique model system to study the gain or loss of vector competence. Using our in vitro louse-rearing system, we infected head and body lice with blood containing B. quintana in order to detect both differences in the proliferation of B. quintana and transcriptional differences of immune-related genes in the lice. B. quintana proliferated rapidly in body lice at 6 days post-infection, but plateaued in head lice at 4 days post-infection. RNAseq and quantitative real-time PCR validation analyses determined gene expression differences. Eight immunoresponse genes were observed to be significantly different with many associated with the Toll pathway: Fibrinogen-like protein, Spaetzle, Defensin 1, Serpin, Scavenger receptor A and Apolipoporhrin 2. Our findings support the hypothesis that body lice, unlike head lice, fight infection from B. quintana only at the later stages of its proliferation. © 2014 The Royal Entomological Society.

Prevalence of head lice in two socio-economically different schools in the center of Izmir City, Turkey.

PubMed

Karakuş, Mehmet; Arıcı, Aylin; Töz, Seray Özensoy; Özbel, Yusuf

2014-01-01

The well-known and common infestation caused by Pediculus humanus capitis is an important public health and a social issue in many communities in the world. The aim of this study was to compare the head louse infestation rate in two schools having pupils from different socio-economic levels in the city center of Izmir. The pupils aged between 6 and 11 years, were screened for the presence of eggs and nymph/adult lice using a fine-tooth head louse comb. A total of 88 and 126 pupils from the schools with low and medium socio-economic level were screened and 24 (27.2%) and 5 (3.96%) of them were found to be positive for head lice, respectively. Overall, the infestation rate among girls was 3.14 times higher than in boys. Head louse infestation is a significant public health problem among primary schools. Increasing the knowledge about pediculosis and self-hygiene would be helpful in successfully reducing head louse infestation in the school setting. School authorities must encourage the parents to look for head lice routinely and a "school nurse" system is needed for effective head louse control in the schools.

Management and Treatment of Human Lice.

PubMed

Sangaré, Abdoul Karim; Doumbo, Ogobara K; Raoult, Didier

2016-01-01

Of the three lice (head, body, and pubic louse) that infest humans, the body louse is the species involved in epidemics of louse-borne typhus, trench fever, and relapsing fever, but all the three cause pediculosis. Their infestations occur today in many countries despite great efforts to maintain high standards of public health. In this review, literature searches were performed through PubMed, Medline, Google Scholar, and EBSCOhost, with key search words of "Pediculus humanus", "lice infestation", "pediculosis", and "treatment"; and controlled clinical trials were viewed with great interest. Removing lice by hand or with a lice comb, heating infested clothing, and shaving the scalp were some of the oldest methods of controlling human lice. Despite the introduction of other resources including cresol, naphthalene, sulfur, mercury, vinegar, petroleum, and insecticides, the numbers of lice infestation cases and resistance have increased. To date, viable alternative treatments to replace insecticides have been developed experimentally in vitro. Today, the development of new treatment strategies such as symbiotic treatment and synergistic treatment (antibiotics + ivermectin) in vitro has proved effective and is promising. Here, we present an overview on managing and treating human lice and highlight new strategies to more effectively fight pediculosis and prevent resistance.

Of lice and math: using models to understand and control populations of head lice.

PubMed

Laguna, María Fabiana; Laguna, Mara Fabiana; Risau-Gusman, Sebastián

2011-01-01

In this paper we use detailed data about the biology of the head louse (pediculus humanus capitis) to build a model of the evolution of head lice colonies. Using theory and computer simulations, we show that the model can be used to assess the impact of the various strategies usually applied to eradicate head lice, both conscious (treatments) and unconscious (grooming). In the case of treatments, we study the difference in performance that arises when they are applied in systematic and non-systematic ways. Using some reasonable simplifying assumptions (as random mixing of human groups and the same mobility for all life stages of head lice other than eggs) we model the contagion of pediculosis using only one additional parameter. It is shown that this parameter can be tuned to obtain collective infestations whose characteristics are compatible with what is given in the literature on real infestations. We analyze two scenarios: One where group members begin treatment when a similar number of lice are present in each head, and another where there is one individual who starts treatment with a much larger threshold ("superspreader"). For both cases we assess the impact of several collective strategies of treatment.

First Detection of the Kdr Mutation T929I in Head Lice (Phthiraptera: Pediculidae) in Schoolchildren of the Metropolitan Area of Nuevo Leon and Yucatan, Mexico.

PubMed

Ponce-Garcia, Gustavo; Villanueva-Segura, Karina; Trujillo-Rodriguez, Gerardo; Rodriguez-Sanchez, Iram P; Lopez-Monroy, Beatriz; Flores, Adriana E

2017-07-01

The head louse Pediculus humanus capitis (De Geer) is a hematophagous ectoparasite that inhabits the human scalp. Infestations by this insect are commonly known as pediculosis, which is more common in younger groups. These infestations are asymptomatic; however, skin irritation from scratching occasionally may cause secondary bacterial infections. In recent years, the prevalence of pediculosis has increased in children; this increase has been attributed to louse resistance to the insecticides used as a control measure for infestation. The aim of the present study was to determine the presence and frequency of the knockdown resistance mutation (kdr) T929I in 468 head lice collected from 32 elementary schools in the metropolitan area of Nuevo Leon (24) and Yucatan (8), Mexico. This is the first report of a knockdown resistance (kdr) mechanism in head lice from Mexico. The T929I mutation was present in all of the sampled schools, with variability observed in its allelic and genotypic frequencies. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Louse-Borne Relapsing Fever with Meningeal Involvement in an Immigrant from Somalia to Italy, October 2015.

PubMed

Zammarchi, Lorenzo; Antonelli, Alberto; Bartolini, Laura; Pecile, Patrizia; Trotta, Michele; Rogasi, Pier Giorgio; Santini, Maria Grazia; Dilaghi, Beatrice; Grifoni, Stefano; Rossolini, Gian Maria; Bartoloni, Alessandro

2016-05-01

Borrelia recurrentis, transmitted by Pediculus humanus humanus, is the etiological agent of louse-borne relapsing fever (LBRF). Currently the main focus of endemicity of LBRF is localized in East African countries. From July 2015 to October 2015, 36 cases of LBRF have been diagnosed in Europe in immigrants from the Horn of Africa. Here we report a case of LBRF with meningitis diagnosed in Florence, Italy, in an immigrant arrived from Somalia. In October 2015, a 19-year-old Somali male presented to the emergency department of the Azienda Ospedaliero Universitaria Careggi, Florence, Italy, with a 3-day history of high fever. The patient had disembarked in Sicily 10 days before admission after a long migration trip from his country of origin. On clinical examination, neck stiffness was found. Main laboratory findings were thrombocytopenia, increased procalcitonin, and increased polymorphonucleates in the cerebrospinal fluid. Suspecting a possible meningitis, the patient was treated with ceftriaxone, pending results of laboratory testing for malaria, and developed severe hypotension that was treated with fluid resuscitation and hydrocortisone. Hemoscopic testing revealed the presence of spirochetes and no malaria parasites. The patient rapidly improved with doxycycline for 7 days and ceftriaxone for 11 days, then was lost to follow-up. Total DNA from blood was extracted, and amplification and sequencing with universal 16S rDNA primers D88 and E94 revealed a 100% identity with B. recurrentis A1. LBRF is a rare but emerging infectious disease among vulnerable displaced immigrants from the Horn of Africa. Since immigrants from endemic areas can carry the vector with them, the infection should be suspected even in subjects with compatible clinical features living in the same place where new arrival immigrants are hosted. Healthcare providers should be aware of this condition to implement adequate diagnostic, therapeutic, and public health measures.

Second-generation sequencing of entire mitochondrial coding-regions (∼15.4 kb) holds promise for study of the phylogeny and taxonomy of human body lice and head lice.

PubMed

Xiong, H; Campelo, D; Pollack, R J; Raoult, D; Shao, R; Alem, M; Ali, J; Bilcha, K; Barker, S C

2014-08-01

The Illumina Hiseq platform was used to sequence the entire mitochondrial coding-regions of 20 body lice, Pediculus humanus Linnaeus, and head lice, P. capitis De Geer (Phthiraptera: Pediculidae), from eight towns and cities in five countries: Ethiopia, France, China, Australia and the U.S.A. These data (∼310 kb) were used to see how much more informative entire mitochondrial coding-region sequences were than partial mitochondrial coding-region sequences, and thus to guide the design of future studies of the phylogeny, origin, evolution and taxonomy of body lice and head lice. Phylogenies were compared from entire coding-region sequences (∼15.4 kb), entire cox1 (∼1.5 kb), partial cox1 (∼700 bp) and partial cytb (∼600 bp) sequences. On the one hand, phylogenies from entire mitochondrial coding-region sequences (∼15.4 kb) were much more informative than phylogenies from entire cox1 sequences (∼1.5 kb) and partial gene sequences (∼600 to ∼700 bp). For example, 19 branches had > 95% bootstrap support in our maximum likelihood tree from the entire mitochondrial coding-regions (∼15.4 kb) whereas the tree from 700 bp cox1 had only two branches with bootstrap support > 95%. Yet, by contrast, partial cytb (∼600 bp) and partial cox1 (∼486 bp) sequences were sufficient to genotype lice to Clade A, B or C. The sequences of the mitochondrial genomes of the P. humanus, P. capitis and P. schaeffi Fahrenholz studied are in NCBI GenBank under the accession numbers KC660761-800, KC685631-6330, KC241882-97, EU219988-95, HM241895-8 and JX080388-407. © 2014 The Royal Entomological Society.

Head Lice Surveillance on a Deregulated OTC-Sales Market: A Study Using Web Query Data

PubMed Central

Lindh, Johan; Magnusson, Måns; Grünewald, Maria; Hulth, Anette

2012-01-01

The head louse, Pediculus humanus capitis, is an obligate ectoparasite that causes infestations of humans. Studies have demonstrated a correlation between sales figures for over-the-counter (OTC) treatment products and the number of humans with head lice. The deregulation of the Swedish pharmacy market on July 1, 2009, decreased the possibility to obtain complete sale figures and thereby the possibility to obtain yearly trends of head lice infestations. In the presented study we wanted to investigate whether web queries on head lice can be used as substitute for OTC sales figures. Via Google Insights for Search and Vårdguiden medical web site, the number of queries on “huvudlöss” (head lice) and “hårlöss” (lice in hair) were obtained. The analysis showed that both the Vårdguiden series and the Google series were statistically significant (p<0.001) when added separately, but if the Google series were already included in the model, the Vårdguiden series were not statistically significant (p = 0.5689). In conclusion, web queries can detect if there is an increase or decrease of head lice infested humans in Sweden over a period of years, and be as reliable a proxy as the OTC-sales figures. PMID:23144923

Comparative efficacy of commercial combs in removing head lice (Pediculus humanus capitis) (Phthiraptera: Pediculidae).

PubMed

Gallardo, Anabella; Toloza, Ariel; Vassena, Claudia; Picollo, María Inés; Mougabure-Cueto, Gastón

2013-03-01

The use of a fine comb for removing lice from the head of the human host is a relevant tool both in the diagnosis of infestations and as part of an integrated control strategy of head lice. The effectiveness of a fine comb depends, in part, on the design and material they are built. The aim of this study was to compare in vivo the efficacy of metal and plastic combs that are currently used in the removal of head lice and eggs worldwide. The space between comb teeth and the length was 0.23 and 13 mm in KSL® plastic, 0.3 and 10.7 mm in NOPUCID® plastic, 0.15 and 31 mm in KSL® metal and 0.09 and 37 mm in ASSY® metal. The assays were performed comparing the combs in pairs: (a) KSL® vs. NOPUCID® plastic combs, (b) KSL® vs. ASSY® metal combs and (c) KSL® plastic comb vs. ASSY® metal comb. The most effective plastic comb was KSL®, removing a higher number of individuals of all stages. The most effective metal comb was ASSY®, removing more insects of all stages (except adults). The comparative test between KSL® plastic and ASSY® metal showed that ASSY® was the most effective in removing head lice and their eggs.

Comparative efficacy of new commercial pediculicides against adults and eggs of Pediculus humanus capitis (head lice).

PubMed

Gallardo, Anabella; Mougabure-Cueto, Gastón; Vassena, Claudia; Picollo, María Inés; Toloza, Ariel Ceferino

2012-05-01

The use of pyrethroids to control head louse infestations have suffered considerable loss of efficacy due to the development of resistance. In the last past years, several new alternative products to synthetic pyrethroids have been developed and are sold in the Argentinean market against head lice. The present study investigated the efficacy of two new Argentinean products Nopucid Qubit® and Nopucid Bio Citrus® and its comparison with two reference products Nyda® and Hedrin®. Nopucid Qubit® is a two-phase lotion containing geraniol and citronellol (phase 1) and ciclopentaxiloxane (phase 2); while Nopucid Bio Citrus® contains dimethicone, ciclopentaxiloxane, and bergamot essential oil. These products are physically acting compounds. The sensitivity of two laboratory assays for testing insecticide activity of new formulations was also compared. Mortality (100%) of motile forms occurred after they were exposed to any product for 1 and 2 min, either by in vitro or ex vivo test. Concerning ovicidal activity, the most effective pediculicides were Nopucid Bio Citrus® and Nyda®, followed by Hedrin® and Nopucid Qubit®. The present study revealed, for the first time, the efficacy of over-the-counter commercial pediculicides available in Argentine (Nopucid Bio Citrus® and Nopucid Qubit®) on either motile stages or eggs against head lice.

Genetic analysis of lice supports direct contact between modern and archaic humans.

PubMed

Reed, David L; Smith, Vincent S; Hammond, Shaless L; Rogers, Alan R; Clayton, Dale H

2004-11-01

Parasites can be used as unique markers to investigate host evolutionary history, independent of host data. Here we show that modern human head lice, Pediculus humanus, are composed of two ancient lineages, whose origin predates modern Homo sapiens by an order of magnitude (ca. 1.18 million years). One of the two louse lineages has a worldwide distribution and appears to have undergone a population bottleneck ca. 100,000 years ago along with its modern H. sapiens host. Phylogenetic and population genetic data suggest that the other lineage, found only in the New World, has remained isolated from the worldwide lineage for the last 1.18 million years. The ancient divergence between these two lice is contemporaneous with splits among early species of Homo, and cospeciation analyses suggest that the two louse lineages codiverged with a now extinct species of Homo and the lineage leading to modern H. sapiens. If these lice indeed codiverged with their hosts ca. 1.18 million years ago, then a recent host switch from an archaic species of Homo to modern H. sapiens is required to explain the occurrence of both lineages on modern H. sapiens. Such a host switch would require direct physical contact between modern and archaic forms of Homo.

Parasitization by Scleroderma guani influences expression of superoxide dismutase genes in Tenebrio molitor.

PubMed

Zhu, Jia-Ying; Ze, Sang-Zi; Stanley, David W; Yang, Bin

2014-09-01

Superoxide dismutase (SOD) is an antioxidant enzyme involved in detoxifying reactive oxygen species. In this study, we identified genes encoding the extracellular and intracellular copper-zinc SODs (ecCuZnSOD and icCuZnSOD) and a manganese SOD (MnSOD) in the yellow mealworm beetle, Tenebrio molitor. The cDNAs for ecCuZnSOD, icCuZnSOD, and MnSOD, respectively, encode 24.55, 15.81, and 23.14 kDa polypeptides, which possess structural features typical of other insect SODs. They showed 20-94% identity to other known SOD sequences from Bombyx mori, Musca domestica, Nasonia vitripennis, Pediculus humanus corporis, and Tribolium castaneum. Expression of these genes was analyzed in selected tissues and developmental stages, and following exposure to Escherichia coli and parasitization by Scleroderma guani. We recorded expression of all three SODs in cuticle, fat body, and hemocytes and in the major developmental stages. Relatively higher expressions were detected in late-instar larvae and pupae, compared to other developmental stages. Transcriptional levels were upregulated following bacterial infection. Analysis of pupae parasitized by S. guani revealed that expression of T. molitor SOD genes was significantly induced following parasitization. We infer that these genes act in immune response and in host-parasitoid interactions. © 2014 Wiley Periodicals, Inc.

Genetic Analysis of Lice Supports Direct Contact between Modern and Archaic Humans

PubMed Central

Smith, Vincent S; Hammond, Shaless L; Rogers, Alan R; Clayton, Dale H

2004-01-01

Parasites can be used as unique markers to investigate host evolutionary history, independent of host data. Here we show that modern human head lice, Pediculus humanus, are composed of two ancient lineages, whose origin predates modern Homo sapiens by an order of magnitude (ca. 1.18 million years). One of the two louse lineages has a worldwide distribution and appears to have undergone a population bottleneck ca. 100,000 years ago along with its modern H. sapiens host. Phylogenetic and population genetic data suggest that the other lineage, found only in the New World, has remained isolated from the worldwide lineage for the last 1.18 million years. The ancient divergence between these two lice is contemporaneous with splits among early species of Homo, and cospeciation analyses suggest that the two louse lineages codiverged with a now extinct species of Homo and the lineage leading to modern H. sapiens. If these lice indeed codiverged with their hosts ca. 1.18 million years ago, then a recent host switch from an archaic species of Homo to modern H. sapiens is required to explain the occurrence of both lineages on modern H. sapiens. Such a host switch would require direct physical contact between modern and archaic forms of Homo. PMID:15502871

Head lice surveillance on a deregulated OTC-sales market: a study using web query data.

PubMed

Lindh, Johan; Magnusson, Måns; Grünewald, Maria; Hulth, Anette

2012-01-01

The head louse, Pediculus humanus capitis, is an obligate ectoparasite that causes infestations of humans. Studies have demonstrated a correlation between sales figures for over-the-counter (OTC) treatment products and the number of humans with head lice. The deregulation of the Swedish pharmacy market on July 1, 2009, decreased the possibility to obtain complete sale figures and thereby the possibility to obtain yearly trends of head lice infestations. In the presented study we wanted to investigate whether web queries on head lice can be used as substitute for OTC sales figures. Via Google Insights for Search and Vårdguiden medical web site, the number of queries on "huvudlöss" (head lice) and "hårlöss" (lice in hair) were obtained. The analysis showed that both the Vårdguiden series and the Google series were statistically significant (p<0.001) when added separately, but if the Google series were already included in the model, the Vårdguiden series were not statistically significant (p = 0.5689). In conclusion, web queries can detect if there is an increase or decrease of head lice infested humans in Sweden over a period of years, and be as reliable a proxy as the OTC-sales figures.

Ovicidal Response of NYDA Formulations on the Human Head Louse (Anoplura: Pediculidae) Using a Hair Tuft Bioassay

PubMed Central

STRYCHARZ, JOSEPH P.; LAO, ALICE R.; ALVES, ANNA-MARIA; CLARK, J. MARSHALL

2012-01-01

Using the in vitro rearing system in conjunction with the hair tuft bioassay, NYDA and NYDA without fragrances formulations (92% wt:wt dimeticones) were 100% ovicidal (0% of treated eggs hatched) after an 8-h exposure of the eggs of the human head louse (Pediculus humanus capitis De Geer) following the manufacturer’s instructions. Comparatively, 78 and 66% of eggs similarly exposed hatched after distilled deionized water or Nix (1% permethrin) treatments, respectively. NYDA and NYDA without fragrances formulations were also statistically and substantially more ovicidal than either distilled deionized water or Nix treatments after 10, 30 min, and 1 h exposures. Only the 10 min exposure of eggs to NYDA and NYDA without fragrances formulations resulted in hatched lice that survived to adulthood (5–8% survival). Of the lice that hatched from eggs exposed to NYDA formulations for 10 min, there were no significant differences in the time it took them to become adults, female fecundity or the viability of eggs laid by surviving females. The longevity of adults, however, was reduced after the 10 min treatments of eggs with NYDA and NYDA without fragrances formulations compared with either the distilled deionized water or Nix treatments. PMID:22493852

Solanum trilobatum extract-mediated synthesis of titanium dioxide nanoparticles to control Pediculus humanus capitis, Hyalomma anatolicum anatolicum and Anopheles subpictus.

PubMed

Rajakumar, Govindasamy; Rahuman, Abdul Abdul; Jayaseelan, Chidambaram; Santhoshkumar, Thirunavukkarasu; Marimuthu, Sampath; Kamaraj, Chinnaperumal; Bagavan, Asokan; Zahir, Abdul Abduz; Kirthi, Arivarasan Vishnu; Elango, Gandhi; Arora, Pooja; Karthikeyan, Rajan; Manikandan, Sivan; Jose, Sujin

2014-02-01

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in paints, printing ink, rubber, paper, cosmetics, sunscreens, car materials, cleaning air products, industrial photocatalytic processes, and decomposing organic matters in wastewater due to their unique physical, chemical, and biological properties. The present study was conducted to assess the antiparasitic efficacies of synthesized TiO2 NPs utilizing leaf aqueous extract of Solanum trilobatum against the adult head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae); larvae of cattle tick Hyalomma anatolicum (a.) anatolicum Koch (Acari: Ixodidae), and fourth instar larvae of malaria vector Anopheles subpictus Grassi (Diptera: Culicidae). The green synthesized TiO2 NPs were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy analysis (EDX), and Atomic force microscopy (AFM). XRD analysis of synthesized TiO2 NPs revealed that the particles were in the form of nanocrystals as evidenced by the major peaks at 2θ values of 27.52°, 36.21°, and 54.43° identified as 110, 101, and 211 reflections, respectively. FTIR spectra exhibited a prominent peak at 3,466 cm(-1) and showed OH stretching due to the alcoholic group, and the OH group may act as a capping agent. SEM images displayed NPs that were spherical, oval in shape, individual, and some in aggregates with an average size of 70 nm. Characterization of the synthesized TiO2 NPs using AFM offered a three-dimensional visualization and uneven surface morphology. The pediculocidal and acaricidal activities of synthesized TiO2 NPs showed the percent mortality of 31, 42, 63, 82, 100; 36, 44, 67, 89, and 100 at 2, 4, 6, 8, and 10 mg/L, respectively, against P. h. capitis and H. a. anatolicum. The average larval percent mortality of synthesized TiO2 NPs was 38, 47, 66, 79, and 100 at 1, 2, 3, 4, and 5 mg/L, respectively, against A. subpictus. The maximum activity was observed in the aqueous leaf extract of S. trilobatum, TiO(OH)2 solutions (bulk), and synthesized TiO2 NPs with LC50 values of 35.14, 25.85, and 4.34 mg/L; 47.15, 29.78, and 4.11 mg/L; and 28.80, 24.01, and 1.94 mg/L, and r (2) values of 0.982, 0.991, and 0.992; 0.947, 0.987, and 0.997; and 0.965, 0.998 and 0.985, respectively, against P. h. capitis, H. a. anatolicum, and A. subpictus. This study provides the first report on the pediculocidal, acaricidal, and larvicidal activity of synthesized TiO2 NPs. This is an ideal eco-friendly, novel, low-cost, and simple approach to satisfy the requirement of large-scale industrial production bearing the advantage for the control of P. h. capitis, H. a. anatolicum, and A. subpictus.

Evolutionary conservation and changes in insect TRP channels.

PubMed

Matsuura, Hironori; Sokabe, Takaaki; Kohno, Keigo; Tominaga, Makoto; Kadowaki, Tatsuhiko

2009-09-10

TRP (Transient Receptor Potential) channels respond to diverse stimuli and thus function as the primary integrators of varied sensory information. They are also activated by various compounds and secondary messengers to mediate cell-cell interactions as well as to detect changes in the local environment. Their physiological roles have been primarily characterized only in mice and fruit flies, and evolutionary studies are limited. To understand the evolution of insect TRP channels and the mechanisms of integrating sensory inputs in insects, we have identified and compared TRP channel genes in Drosophila melanogaster, Bombyx mori, Tribolium castaneum, Apis mellifera, Nasonia vitripennis, and Pediculus humanus genomes as part of genome sequencing efforts. All the insects examined have 2 TRPV, 1 TRPN, 1 TRPM, 3 TRPC, and 1 TRPML subfamily members, demonstrating that these channels have the ancient origins in insects. The common pattern also suggests that the mechanisms for detecting mechanical and visual stimuli and maintaining lysosomal functions may be evolutionarily well conserved in insects. However, a TRPP channel, the most ancient TRP channel, is missing in B. mori, A. mellifera, and N. vitripennis. Although P. humanus and D. melanogaster contain 4 TRPA subfamily members, the other insects have 5 TRPA subfamily members. T. castaneum, A. mellifera, and N. vitripennis contain TRPA5 channels, which have been specifically retained or gained in Coleoptera and Hymenoptera. Furthermore, TRPA1, which functions for thermotaxis in Drosophila, is missing in A. mellifera and N. vitripennis; however, they have other Hymenoptera-specific TRPA channels (AmHsTRPA and NvHsTRPA). NvHsTRPA expressed in HEK293 cells is activated by temperature increase, demonstrating that HsTRPAs function as novel thermal sensors in Hymenoptera. The total number of insect TRP family members is 13-14, approximately half that of mammalian TRP family members. As shown for mammalian TRP channels, this may suggest that single TRP channels are responsible for integrating diverse sensory inputs to maintain the insect sensory systems. The above results demonstrate that there are both evolutionary conservation and changes in insect TRP channels. In particular, the evolutionary processes have been accelerated in the TRPA subfamily, indicating divergence in the mechanisms that insects use to detect environmental temperatures.

Identification of repellent odorants to the body louse, Pediculus humanus corporis, in clove essential oil.

PubMed

Iwamatsu, Takuma; Miyamoto, Daisuke; Mitsuno, Hidefumi; Yoshioka, Yoshiaki; Fujii, Takeshi; Sakurai, Takeshi; Ishikawa, Yukio; Kanzaki, Ryohei

2016-04-01

The control of body lice is an important issue for human health and welfare because lice act as vectors of disease such as typhus, relapsing fever, and trench fever. Body lice exhibit avoidance behavior to some essential oils, including clove essential oil. Therefore, odorants containing clove essential oil components may potentially be useful in the development of repellents to body lice. However, such odorants that induce avoidance behavior in body lice have not yet been identified from clove essential oil. Here, we established an analysis method to evaluate the avoidance behavior of body lice to specific odorants. The behavioral analysis of the body lice in response to clove essential oil and its constituents revealed that eugenol, a major component of clove essential oil, has strong repellent effect on body lice, whereas the other components failed to induce obvious avoidance behavior. A comparison of the repellent effects of eugenol with those of other structurally related odorants revealed possible moieties that are important for the avoidance effects to body lice. The repellent effect of eugenol to body lice was enhanced by combining it with the other major component of clove essential oil, β-caryophyllene. We conclude that a synthetic blend of eugenol and β-caryophyllene is the most effective repellent to body lice. This finding will be valuable as the potential use of eugenol as body lice repellent.

Detection of bacterial pathogens including potential new species in human head lice from Mali

PubMed Central

Amanzougaghene, Nadia; Fenollar, Florence; Sangaré, Abdoul Karim; Sissoko, Mahamadou S.; Doumbo, Ogobara K.; Raoult, Didier

2017-01-01

In poor African countries, where no medical and biological facilities are available, the identification of potential emerging pathogens of concern at an early stage is challenging. Head lice, Pediculus humanus capitis, have a short life, feed only on human blood and do not transmit pathogens to their progeny. They are, therefore, a perfect tool for the xenodiagnosis of current or recent human infection. This study assessed the occurrence of bacterial pathogens from head lice collected in two rural villages from Mali, where a high frequency of head lice infestation had previously been reported, using molecular methods. Results show that all 600 head lice, collected from 117 individuals, belonged to clade E, specific to West Africa. Bartonella quintana, the causative agent of trench fever, was identified in three of the 600 (0.5%) head lice studied. Our study also shows, for the first time, the presence of the DNA of two pathogenic bacteria, namely Coxiella burnetii (5.1%) and Rickettsia aeschlimannii (0.6%), detected in human head lice, as well as the DNA of potential new species from the Anaplasma and Ehrlichia genera of unknown pathogenicity. The finding of several Malian head lice infected with B. quintana, C. burnetii, R. aeschlimannii, Anaplasma and Ehrlichia is alarming and highlights the need for active survey programs to define the public health consequences of the detection of these emerging bacterial pathogens in human head lice. PMID:28931077

Identification and gene-silencing of a putative odorant receptor transcription factor in Varroa destructor: possible role in olfaction.

PubMed

Singh, N K; Eliash, N; Stein, I; Kamer, Y; Ilia, Z; Rafaeli, A; Soroker, V

2016-04-01

The ectoparasitic mite Varroa destructor is one of the major threats to apiculture. Using a behavioural choice bioassay, we determined that phoretic mites were more successful in reaching a bee than reproductive mites, suggesting an energy trade-off between reproduction and host selection. We used both chemo-ecological and molecular strategies to identify the regulation of the olfactory machinery of Varroa and its association with reproduction. We focused on transcription regulation. Using primers designed to the conserved DNA binding region of transcription factors, we identified a gene transcript in V. destructor homologous to the pheromone receptor transcription factor (PRTF) gene of Pediculus humanus corporis. Quantitative PCR (qPCR) revealed that this PRTF-like gene transcript is expressed in the forelegs at higher levels than in the body devoid of forelegs. Subsequent comparative qPCR analysis showed that transcript expression was significantly higher in the phoretic as compared to the reproductive stage. Electrophysiological and behavioural studies revealed a reduction in the sensitivity of PRTF RNA interference-silenced mites to bee headspace, consistent with a reduction in the mites' ability to reach a host. In addition, vitellogenin expression was stimulated in PRTF-silenced mites to similar levels as found in reproductive mites. These data shed light upon the regulatory mechanism of host chemosensing in V. destructor. © 2016 The Royal Entomological Society.

The History of Epidemic Typhus.

PubMed

Angelakis, Emmanouil; Bechah, Yassina; Raoult, Didier

2016-08-01

Epidemic typhus caused by Rickettsia prowazekii is one of the oldest pestilential diseases of humankind. The disease is transmitted to human beings by the body louse Pediculus humanus corporis and is still considered a major threat by public health authorities, despite the efficacy of antibiotics, because poor sanitary conditions are conducive to louse proliferation. Epidemic typhus has accompanied disasters that impact humanity and has arguably determined the outcome of more wars than have soldiers and generals. The detection, identification, and characterization of microorganisms in ancient remains by paleomicrobiology has permitted the diagnosis of past epidemic typhus outbreaks through the detection of R. prowazekii. Various techniques, including microscopy and immunodetection, can be used in paleomicrobiology, but most of the data have been obtained by using PCR-based molecular techniques on dental pulp samples. Paleomicrobiology enabled the identification of the first outbreak of epidemic typhus in the 18th century in the context of a pan-European great war in the city of Douai, France, and supported the hypothesis that typhus was imported into Europe by Spanish soldiers returning from America. R. prowazekii was also detected in the remains of soldiers of Napoleon's Grand Army in Vilnius, Lithuania, which indicates that Napoleon's soldiers had epidemic typhus. The purpose of this article is to underscore the modern comprehension of clinical epidemic typhus, focus on the historical relationships of the disease, and examine the use of paleomicrobiology in the detection of past epidemic typhus outbreaks.

Resistance and the control of lice on humans and production animals.

PubMed

Levot, G

2000-03-01

Phthiraptera (lice) are specialised insects adapted to parasitise many warm-blooded vertebrates, including domestic animals and humans. Often, attempts by the host to alleviate the irritation created by lice, causes derangement of the hair/fur coat. Unless treated, this derangement may cause economic losses due to hide damage and/or downgrading of wool/hair/fur. In 1981, application of aqueous insecticide solutions (dipping) for the control of sheep body lice (Bovicola ovis) was largely superseded by off-shears pyrethroid "pour-on" treatments. By 1985, several field failures with these products were found to be due to low-level (20x) insecticide resistance. In 1990, high-level (640x) resistance was diagnosed in a New South Wales population. However, despite 30+years use, organophosphate-based products are still usually effective. Until recently, cattle lice caused little concern. Treatments were applied mainly for aesthetic reasons when cattle were to be presented for sale, and also to prevent damage to fences by rubbing cattle. However, the introduction of quality-management programmes have raised awareness of the economic losses due to hide damage associated with lice infestations. Emerging industries such as emu and alpaca farming have raised the pest status of other louse species, and necessitated insecticidal intervention. In humans, attempts to control head lice, Pediculus humanus capitis, infestations have repeatedly failed around the world.

Detection of bacterial pathogens including potential new species in human head lice from Mali.

PubMed

Amanzougaghene, Nadia; Fenollar, Florence; Sangaré, Abdoul Karim; Sissoko, Mahamadou S; Doumbo, Ogobara K; Raoult, Didier; Mediannikov, Oleg

2017-01-01

In poor African countries, where no medical and biological facilities are available, the identification of potential emerging pathogens of concern at an early stage is challenging. Head lice, Pediculus humanus capitis, have a short life, feed only on human blood and do not transmit pathogens to their progeny. They are, therefore, a perfect tool for the xenodiagnosis of current or recent human infection. This study assessed the occurrence of bacterial pathogens from head lice collected in two rural villages from Mali, where a high frequency of head lice infestation had previously been reported, using molecular methods. Results show that all 600 head lice, collected from 117 individuals, belonged to clade E, specific to West Africa. Bartonella quintana, the causative agent of trench fever, was identified in three of the 600 (0.5%) head lice studied. Our study also shows, for the first time, the presence of the DNA of two pathogenic bacteria, namely Coxiella burnetii (5.1%) and Rickettsia aeschlimannii (0.6%), detected in human head lice, as well as the DNA of potential new species from the Anaplasma and Ehrlichia genera of unknown pathogenicity. The finding of several Malian head lice infected with B. quintana, C. burnetii, R. aeschlimannii, Anaplasma and Ehrlichia is alarming and highlights the need for active survey programs to define the public health consequences of the detection of these emerging bacterial pathogens in human head lice.

Severe head lice infestation in an Andean mummy of Arica, Chile.

PubMed

Arriaza, Bernardo; Orellana, Nancy C; Barbosa, Helene S; Menna-Barreto, Rubem F S; Araújo, Adauto; Standen, Vivien

2012-04-01

Pediculus humanus capitis is an ancient human parasite, probably inherited from pre-hominid times. Infestation appears as a recurrent health problem throughout history, including in pre-Columbian populations. Here, we describe and discuss the occurrence of pre-Columbian pediculosis in the Andean region of the Atacama Desert. Using a light microscope and scanning electron microscopy, we studied a highly infested Maitas Chiribaya mummy from Arica in northern Chile dating to 670-990 calibrated years A.D. The scalp and hair of the mummy were almost completely covered by nits and adult head lice. Low- and high-vacuum scanning electron microscopy revealed a well-preserved morphology of the eggs. In addition, the excellent preservation of the nearly 1,000-yr-old adult head lice allowed us to observe and characterize the head, antennae, thorax, abdomen, and legs. Leg segmentation, abdominal spiracles, and sexual dimorphism also were clearly observed. The preservation of the ectoparasites allowed us to examine the micromorphology using scanning electron microscopy; the opercula, aeropyles, and spiracles were clearly visible. This case study provides strong evidence that head lice were a common nuisance for Andean farmers and herders. Head lice are transmitted by direct head-to-head contact; thus, this ancient farmer and herder was potentially infesting other people. The present study contributes to the body of research focusing on lice in ancient populations.

Do drowning and anoxia kill head lice?

PubMed

Candy, Kerdalidec; Brun, Sophie; Nicolas, Patrick; Durand, Rémy; Charrel, Remi N; Izri, Arezki

2018-01-01

Chemical, physical, and mechanical methods are used to control human lice. Attempts have been made to eradicate head lice Pediculus humanus capitis by hot air, soaking in various fluids or asphyxiation using occlusive treatments. In this study, we assessed the maximum time that head lice can survive anoxia (oxygen deprivation) and their ability to survive prolonged water immersion. We also observed the ingress of fluids across louse tracheae and spiracle characteristics contrasting with those described in the literature. We showed that 100% of lice can withstand 8 h of anoxia and 12.2% survived 14 h of anoxia; survival was 48.9% in the untreated control group at 14 h. However, all lice had died following 16 h of anoxia. In contrast, the survival rate of water-immersed lice was significantly higher when compared with non-immersed lice after 6 h (100% vs. 76.6%, p = 0.0037), and 24 h (50.9% vs. 15.9%, p = 0.0003). Although water-immersed lice did not close their spiracles, water did not penetrate into the respiratory system. In contrast, immersion in colored dimeticone/cyclomethicone or colored ethanol resulted in penetration through the spiracles and spreading to the entire respiratory system within 30 min, leading to death in 100% of the lice. © K. Candy et al., published by EDP Sciences, 2018.

Mechanism of phospho-ubiquitin induced PARKIN activation

PubMed Central

Wauer, Tobias; Simicek, Michal; Schubert, Alexander; Komander, David

2016-01-01

Summary The E3 ubiquitin ligase PARKIN (encoded by PARK2) and the protein kinase PINK1 (encoded by PARK6) are mutated in autosomal recessive juvenile Parkinsonism (AR-JP) and work together in the disposal of damaged mitochondria by mitophagy1–3. PINK1 is stabilised on the outside of depolarised mitochondria, and phosphorylates poly-ubiquitin (polyUb)4–8 as well as the PARKIN Ub-like (Ubl) domain9,10. These phosphorylation events lead to PARKIN recruitment to mitochondria, and activation by an unknown allosteric mechanism4–12. Here we present the crystal structure of Pediculus humanus PARKIN in complex with Ser65-phosphorylated ubiquitin (phosphoUb), revealing the molecular basis for PARKIN recruitment and activation. The phosphoUb binding site on PARKIN comprises a conserved phosphate pocket and harbours residues mutated in AR-JP patients. PhosphoUb binding leads to straightening of a helix in the RING1 domain, and the resulting conformational changes release the Ubl domain from the PARKIN core; this activates PARKIN. Moreover, phosphoUb-mediated Ubl release enhances Ubl phosphorylation by PINK1, leading to conformational changes within the Ubl domain and stabilisation of an open, active conformation of PARKIN. We redefine the role of the Ubl domain not only as an inhibitory13 but also as an activating element that is restrained in inactive PARKIN and released by phosphoUb. Our work opens new avenues to identify small molecule PARKIN activators. PMID:26161729

Influence of the formulations in removing eggs of Pediculus humanus capitis (Phthiraptera: Pediculidae).

PubMed

Ortega-Insaurralde, Isabel; Toloza, Ariel Ceferino; Picollo, María Inés; Vassena, Claudia

2014-09-01

Head lice lay eggs in human head hairs in order to reproduce. There is a difficulty associated to the process of detaching these eggs: they are tightly gripped to the hair by a secretion produced by female head lice. The physical removal of eggs has become an important part of treatment of louse infestations. The finding of new products to loosen the eggs is necessary to avoid mistaken diagnosis or reinfestations. This work aimed to compare different kinds of pediculicide formulations in order to find if their presentations represented differences in the egg remover effect. We also wanted to present a new device to test the efficacy of the egg remover formulations. Products with creamy presentations (Bio infant lice and egg remover and hair conditioner) and one containing dimethicone (Nyda) showed the lower mean forces compared with the control (lower mean forces represented best removal activity). Whereas, the Biferdil egg remover (gel) and Nopucid Tribit (hydroalcoholic lotion) had no egg removal effect, presenting the highest mean forces (177.82 and 189.99 mN, respectively) compared with the control. Additionally, we proposed a removal index (RI) to compare the efficacy of different products on the egg removal activity (RI > 0, good performance). The higher index values were for Bio infant lice and egg remover (0.72) and Biferdil hair conditioner (0.58). The lowest index values were for Biferdil egg remover (-0.26) and Nopucid Tribit (-0.35).The formulation of over the counter pediculicides in the egg remover effect was discussed.

Geographical distribution of pyrethroid resistance allele frequency in head lice (Phthiraptera: Pediculidae) from Argentina.

PubMed

Toloza, Ariel Ceferino; Ascunce, Marina S; Reed, David; Picollo, María Inés

2014-01-01

The human head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), is an obligate ectoparasite that causes pediculosis capitis and has parasitized humans since the beginning of humankind. Head louse infestations are widespread throughout the world and have been increasing since the early 1990s partially because of ineffective pediculicides. In Argentina, the overuse of products containing pyrethroids has led to the development of resistant louse populations. Pyrethroid insecticides act on the nervous system affecting voltage-sensitive sodium channels. Three point mutations at the corresponding amino acid sequence positions M815I, T917I, and L920F in the voltage-gated sodium channel gene are responsible for contributing to knockdown resistance (kdr). The management of pyrethroid resistance requires either early detection or the characterization of the mechanisms involved in head louse populations. In the current study, we estimated the distribution of kdr alleles in 154 head lice from six geographical regions of Argentina. Pyrethroid resistance kdr alleles were found in high frequencies ranging from 67 to 100%. Of these, 131 (85.1%) were homozygous resistant, 13 (8.4%) were homozygous susceptible, and 10 (6.5%) were heterozygous. Exact tests for the Hardy-Weinberg equilibrium for each location showed that genotype frequencies differed significantly from expectation in four of the six sites studied. These results show that pyrethroid resistance is well established reaching an overall frequency of 88%, thus close to fixation. With 30 yr of pyrethroid-based pediculicides use in Argentina, kdr resistance has evolved rapidly among these head louse populations.

Efficacy of spray formulations containing binary mixtures of clove and eucalyptus oils against susceptible and pyrethroid/ malathion-resistant head lice (Anoplura: Pediculidae).

PubMed

Choi, Han-Young; Yang, Young-Cheol; Lee, Si Hyeock; Clark, J Marshall; Ahn, Young-Joon

2010-05-01

The control efficacy of clove, Eugenia caryophyllata, and eucalyptus, Eucalyptus globulus, essential oils and 15 formulations containing these essential oils alone (8, 12, and 15% sprays) and their binary mixtures (7:3, 5:5, and 3:7 by weight) against adult females of insecticide-susceptible KR-HL and dual malathion- and permethrin-resistant BR-HL strains of head louse, Pediculus humanus capitis (De Geer), was examined by using contact plus fumigant and human hair wig (placed over the head of mannequin) mortality bioassays. In contact plus fumigant mortality bioassay, essential oils from eucalyptus (0.225 mg/cm2) and clove (1.149 mg/cm2) were less effective than either d-phenothrin (0.0029 mg/cm2) or pyrethrum (0.0025 mg/cm2) based on 6-h median lethal concentration values. However, the efficacies of eucalyptus and clove oils were almost identical against females fromn both strains, despite high levels of resistance of the BR-HL females to d-phenothrin (resistance ratio, 667) and pyrethrum (resistance ratio, 754). In human hair wig mortality bioassay, eucalyptus oil spray treatment gave better control efficacy than either spray treatment with clove oil alone or their binary mixtures. Thus, eucalyptus applied as 8% sprays (15 or 20 ml) appears to provide effective protection against pediculosis even to insecticide-resistant head louse populations. Once the safety issues resolved, covering the treated hair and scalp with bath shower cap or hat would ensure the fumigant action of the essential oil.

Evolution of extensively fragmented mitochondrial genomes in the lice of humans.

PubMed

Shao, Renfu; Zhu, Xing-Quan; Barker, Stephen C; Herd, Kate

2012-01-01

Bilateral animals are featured by an extremely compact mitochondrial (mt) genome with 37 genes on a single circular chromosome. The human body louse, Pediculus humanus, however, has its mt genes on 20 minichromosomes. We sequenced the mt genomes of two other human lice: the head louse, P. capitis, and the pubic louse, Pthirus pubis. Comparison among the three human lice revealed the presence of fragmented mt genomes in their most recent common ancestor, which lived ∼7 Ma. The head louse has exactly the same set of mt minichromosomes as the body louse, indicating that the number of minichromosomes, and the gene content and gene arrangement in each minichromosome have remained unchanged since the body louse evolved from the head louse ∼107,000 years ago. The pubic louse has the same pattern of one protein-coding or rRNA gene per minichromosome (except one minichromosome with two protein-coding genes, atp6 and atp8) as the head louse and the body louse. This pattern is apparently ancestral to all human lice and has been stable for at least 7 Myr. Most tRNA genes of the pubic louse, however, are on different minichromosomes when compared with their counterparts in the head louse and the body louse. It is evident that rearrangement of four tRNA genes (for leucine, arginine and glycine) was due to gene-identity switch by point mutation at the third anticodon position or by homologous recombination, whereas rearrangement of other tRNA genes was by gene translocation between minichromosomes, likely caused by minichromosome split via gene degeneration and deletion.

Efficacy of the LouseBuster, a new medical device for treating head lice (Anoplura:Pediculidae).

PubMed

Bush, Sarah E; Rock, Alex N; Jones, Sherri L; Malenke, Jael R; Clayton, Dale H

2011-01-01

Human head lice (Pediculus humanus capitis De Geer) occur worldwide and infest millions of children and adults every year. Head lice infestations, which are known as pediculosis capitis, are psychologically stressful, physically irritating, and are one of the leading causes of K-6 school absence. The prevalence of head lice in many countries is increasing rapidly because of resistance to chemicals used in many head lice treatments. We tested the efficacy of an alternative method for controlling head lice, the LouseBuster, a custom-built medical device designed to kill head lice and their eggs using controlled, heated air. A total of 56 infested subjects was treated with the LouseBuster, and the efficacy of the treatment was evaluated by comparing the viability of lice and eggs on randomly assigned pre- and posttreatment sides of each subject's scalp. We evaluate treatment efficacy in the hands of novice versus experienced operators. We also evaluate treatment efficacy on different hair types and at different ambient humidities. Overall mortality of lice and eggs was 94.8% after treatment by experienced operators. Novice operators also achieved good results after a short training session; their results did not differ significantly from those of experienced operators. No adverse events were associated with the LouseBuster treatment. The LouseBuster is efficacious for killing head lice and their eggs. The use of heated air is appealing because it is a fast, safe, nonchemical treatment. Head lice are also unlikely to evolve resistance to desiccation, which is the apparent mode of action.

Head Lice of Pygmies Reveal the Presence of Relapsing Fever Borreliae in the Republic of Congo.

PubMed

Amanzougaghene, Nadia; Akiana, Jean; Mongo Ndombe, Géor; Davoust, Bernard; Nsana, Nardiouf Sjelin; Parra, Henri-Joseph; Fenollar, Florence; Raoult, Didier; Mediannikov, Oleg

2016-12-01

Head lice, Pediculus humanus capitis, occur in four divergent mitochondrial clades (A, B, C and D), each having particular geographical distributions. Recent studies suggest that head lice, as is the case of body lice, can act as a vector for louse-borne diseases. Therefore, understanding the genetic diversity of lice worldwide is of critical importance to our understanding of the risk of louse-borne diseases. Here, we report the results of the first molecular screening of pygmies' head lice in the Republic of Congo for seven pathogens and an analysis of lice mitochondrial clades. We developed two duplex clade-specific real-time PCRs and identified three major mitochondrial clades: A, C, and D indicating high diversity among the head lice studied. We identified the presence of a dangerous human pathogen, Borrelia recurrentis, the causative agent of relapsing fever, in ten clade A head lice, which was not reported in the Republic of Congo, and B. theileri in one head louse. The results also show widespread infection among head lice with several species of Acinetobacter. A. junii was the most prevalent, followed by A. ursingii, A. baumannii, A. johnsonii, A. schindleri, A. lwoffii, A. nosocomialis and A. towneri. Our study is the first to show the presence of B. recurrentis in African pygmies' head lice in the Republic of Congo. This study is also the first to report the presence of DNAs of B. theileri and several species of Acinetobacter in human head lice. Further studies are needed to determine whether the head lice can transmit these pathogenic bacteria from person to another.

Association of Drought with Typhus Epidemics in Central Mexico

NASA Astrophysics Data System (ADS)

Acuna-Soto, R.; Stahle, D.; Villanueva Diaz, J.; Therrell, M.

2007-05-01

Typhus is an acute infectious disease caused by the bacteria Rickettsia prowazekii, which is transmitted among humans by the body lice (Pediculus humanus corporis). The disease is highly contagious and transmission is favored in populations living in crowded conditions. Under these circumstances, typhus transmission is facilitated by factors that favor the colonization and proliferation of body lice such as absence of personal hygiene and wearing the same clothes for long periods of time. Historically, periods of war and famine were associated with devastating epidemics with high mortality rates in many parts of the world. Central Mexico has a long record of typhus epidemics. In this region, at > 2000 meters above sea level, the disease was endemic and occurred with a seasonal pattern in winter, with occasional large epidemics. Recently, we completed a chronology of epidemics in Mexico. A total of 22 well-defined major typhus epidemics were identified between 1650 and 1920. All of them caused periods of increased mortality that lasted 2 - 4 years (more than one standard deviation from the previous ten year period). The record of typhus epidemics was evaluated against the tree-ring record of Cuauhtmoc La Fragua, Puebla. This chronology, based on Douglas fir, has demonstrated to be a faithful record of precipitation in central Mexico. The results indicate that a statistically significant drought (t test, p < .05) prevailed during the first year of all 22 large outbreaks of typhus in recent Mexican history. No distinction is made between times of peace and war. This indicates that drought alone was capable of inducing the social conditions for increased transmission of typhus in pre-industrial central Mexico.

The Epidemiology and Geographic Distribution of Relapsing Fever Borreliosis in West and North Africa, with a Review of the Ornithodoros erraticus Complex (Acari: Ixodida)

PubMed Central

Trape, Jean-François; Diatta, Georges; Arnathau, Céline; Bitam, Idir; Sarih, M’hammed; Belghyti, Driss; Bouattour, Ali; Elguero, Eric; Vial, Laurence; Mané, Youssouph; Baldé, Cellou; Pugnolle, Franck; Chauvancy, Gilles; Mahé, Gil; Granjon, Laurent; Duplantier, Jean-Marc

2013-01-01

Background Relapsing fever is the most frequent bacterial disease in Africa. Four main vector / pathogen complexes are classically recognized, with the louse Pediculus humanus acting as vector for B. recurrentis and the soft ticks Ornithodoros sonrai, O. erraticus and O. moubata acting as vectors for Borrelia crocidurae, B. hispanica and B. duttonii, respectively. Our aim was to investigate the epidemiology of the disease in West, North and Central Africa. Methods And Findings From 2002 to 2012, we conducted field surveys in 17 African countries and in Spain. We investigated the occurrence of Ornithodoros ticks in rodent burrows in 282 study sites. We collected 1,629 small mammals that may act as reservoir for Borrelia infections. Using molecular methods we studied genetic diversity among Ornithodoros ticks and Borrelia infections in ticks and small mammals. Of 9,870 burrows investigated, 1,196 (12.1%) were inhabited by Ornithodoros ticks. In West Africa, the southern and eastern limits of the vectors and Borrelia infections in ticks and small mammals were 13°N and 01°E, respectively. Molecular studies revealed the occurrence of nine different Ornithodoros species, including five species new for science, with six of them harboring Borrelia infections. Only B. crocidurae was found in West Africa and three Borrelia species were identified in North Africa: B. crocidurae, B. hispanica, and B. merionesi. Conclusions Borrelia Spirochetes responsible for relapsing fever in humans are highly prevalent both in Ornithodoros ticks and small mammals in North and West Africa but Ornithodoros ticks seem absent south of 13°N and small mammals are not infected in these regions. The number of Ornithodoros species acting as vector of relapsing fever is much higher than previously known. PMID:24223812

A systematic literature review of pediculosis due to head lice in the Pacific Island Countries and Territories: what country specific research on head lice is needed?

PubMed Central

2014-01-01

Background Lack of guidelines on control of pediculosis in the Solomon Islands led to a search for relevant evidence on head lice in the Pacific Island Countries and Territories (PICTs). The aim of this search was to systematically evaluate evidence in the peer reviewed literature on pediculosis due to head lice (Pediculus humanus var capitis) in the 22 PICTs from the perspective of its value in informing national guidelines and control strategies. Methods PubMed, Web of Science, CINAHL and Scopus were searched using the terms (pediculosis OR head lice) AND each of the 22 PICTs individually. PRISMA methodology was used. Exclusion criteria were: i) not on topic; ii) publications on pediculosis not relevant to the country of the particular search; iii) in grey literature. Results Of 24 publications identified, only 5 were included. Four related to treatment and one to epidemiology. None contained information relevant to informing national guidelines. Conclusions Current local evidence on head lice in the PICTs is minimal and totally inadequate to guide any recommendations for treatment or control. We recommend that local research is required to generate evidence on: i) epidemiology; ii) knowledge, attitudes and practices of health care providers and community members; iii) efficacy of local commercially available pharmaceutical treatments and local customary treatments; iv) acceptability, accessibility and affordability of available treatment strategies; and iv) appropriate control strategies for families, groups and institutions. We also recommend that operational research be done by local researchers based in the PICTs, supported by experienced head lice researchers, using a two way research capacity building model. PMID:24962507

Arrestant Effect of Human Scalp Components on Head Louse (Phthiraptera: Pediculidae) Behavior.

PubMed

Ortega-Insaurralde, Isabel; Ceferino Toloza, Ariel; Gonzalez-Audino, Paola; Inés Picollo, María

2017-03-01

Relevant evidence has shown that parasites process host-related information using chemical, visual, tactile, or auditory cues. However, the cues that are involved in the host-parasite interaction between Pediculus humanus capitis (De Geer 1767) and humans have not been identified yet. In this work, we studied the effect of human scalp components on the behavior of adult head lice. Filter paper segments were rubbed on volunteers' scalps and then placed in the experimental arena, where adult head lice were individually tested. The movement of the insects was recorded for each arena using the software EthoVision. Average movement parameters were calculated for the treatments in the bioassays such as total distance, velocity, number of times a head louse crossed between zones of the arena, and time in each zone of the arena. We found that scalp components induced head lice to decrease average locomotor activity and to remain arrested on the treated paper. The effect of the ageing of human scalp samples in the response of head lice was not statistically significant (i.e., human scalp samples of 4, 18, 40, and 60 h of ageing did not elicit a significant change in head louse behavior). When we analyzed the effect of the sex in the response of head lice to human scalp samples, males demonstrated significant differences. Our results showed for the first time the effect of host components conditioning head lice behavior. We discuss the role of these components in the dynamic of head lice infestation. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Pediculicidal effect of herbal shampoo against Pediculus humanus capitis in vitro.

PubMed

Watcharawit, R; Soonwera, M

2013-06-01

Human head lice infestation is an important public health problem in Thailand. Lice resistance is increasing, chemical pediculicides have lost their efficacy and thus alternative products such as herbal shampoos have been proposed to treat lice infestation. The present study investigated the efficacy of twenty nine herbal shampoos based on zinbiberaceae plants, piperaceae plants and native plants against human head lice and compared them with malathion shampoo (A-lices shampoo®: 1% w/v malathion) and commercial shampoo (BabiMild Natural'N Mild®) in order to assess their in vitro efficacy. All herbal shampoo were more effective than commercial shampoo with 100% mortality at 60 seconds and LT50 values ranged from 11.30 to 31.97 seconds, meanwhile, commercial shampoo caused 14.0-15.0% mortality and LT50 values ranged from 83.96 to 87.43 seconds. The nine herbal shampoos from Zingiber cassumunar, Piper betle, Piper ribesioides, Averrhoa bilimbi, Clitoria ternatea, Plectranthus amboincus, Myristica fragrans, Tacca chantrieri and Zanthoxylum limonella were more effective pediculicide than malathion shampoo with 100% mortality at 30 seconds and LT50 values ranged from 11.30-13.58 seconds, on the other hand malathion shampoo showed LT50 values ranging from 12.39 to 13.67 seconds. LT50 values indicated the order of pediculicidal activity in the herbal shampoos as Z. cassumunar shampoo > P. betle shampoo > Za. limonella shampoo > Av. bilimbi shampoo > P. ribesioides shampoo > My. fragrans shampoo > T. chantrieri shampoo > Pl. amboincus shampoo. Our data showed that eight of the twenty nine herbal shampoos in this study were of high potential pediculicide to human head lice treatments for Thai children.

Determination, mechanism and monitoring of knockdown resistance in permethrin-resistant human head lice, Pediculus humanus capitis

PubMed Central

Clark, J. Marshall

2009-01-01

Permethrin resistance has been reported worldwide and clinical failures to commercial pediculicides containing permethrin have likewise occurred. Permethrin resistance in head lice populations from the U.S. is widespread but is not yet uniform and the level of resistance is relatively low (~4–8 fold). Permethrin-resistant lice are cross-resistant to pyrethrins, PBO-synergized pyrethrins and to DDT. Nix®, when applied to human hair tufts following manufacture’s instructions, did not provide 100% control when assessed by the hair tuft bioassay in conjunction with the in vitro rearing system. Resistance to permethrin is due to knockdown resistance (kdr), which is the result of three point mutations within the α-subunit gene of the voltage-gated sodium channel that causes amino acid substitutions, leading to nerve insensitivity. A three-tiered resistance monitoring system has been established based on molecular resistance detection techniques. Quantitative sequencing (QS) has been developed to predict the kdr allele frequency in head lice at a population level. The speed, simplicity and accuracy of QS made it an ideal candidate for a routine primary resistance monitoring tool to screen a large number of louse populations as an alternative to conventional bioassay. As a secondary monitoring method, real-time PASA (rtPASA) has been devised for a more precise determination of low resistance allele frequencies. To obtain more detailed information on resistance allele zygosity, as well as allele frequency, serial invasive signal amplification reaction (SISAR) has been developed as an individual genotyping method. Our approach of using three tiers of molecular resistance detection should facilitate large-scale routine resistance monitoring of permethrin resistance in head lice using field-collected samples. PMID:20161186

The sex ratio distortion in the human head louse is conserved over time

PubMed Central

Perotti, M Alejandra; Catalá, Silvia S; Ormeño, Analía del V; Żelazowska, Monika; Biliński, Szczepan M; Braig, Henk R

2004-01-01

Background At the turn of the 19th century the first observations of a female-biased sex ratio in broods and populations of the head louse, Pediculus humanus capitis, had been reported. A study by Buxton in 1940 on the sex ratio of lice on prisoners in Ceylon is still today the subject of reanalyses. This sex ratio distortion had been detected in ten different countries. In the last sixty years no new data have been collected, especially on scalp infestations under economically and socially more developed conditions. Results Here we report a female bias of head lice in a survey of 480 school children in Argentina. This bias is independent of the intensity of the pediculosis, which makes local mate competition highly unlikely as the source of the aberrant sex ratio; however, other possible adaptive mechanisms cannot be discounted. These lice as well as lice from pupils in Britain were carrying several strains of the endosymbiotic bacterium Wolbachia pipientis, one of the most wide spread intracellular sex ratio distorters. Similar Wolbachia strains are also present in the pig louse, Haematopinus suis, suggesting that this endosymbiont might have a marked influence on the biology of the whole order. The presence of a related obligate nutritional bacterium in lice prevents the investigation of a causal link between sex ratio and endosymbionts. Conclusions Regardless of its origin, this sex ratio distortion in head lice that has been reported world wide, is stable over time and is a remarkable deviation from the stability of frequency-dependent selection of Fisher's sex ratio. A female bias first reported in 1898 is still present over a hundred years and a thousand generations later. PMID:15140268

Ex vivo effectiveness of French over-the-counter products against head lice (Pediculus humanus capitis De Geer, 1778).

PubMed

Combescot-Lang, Catherine; Vander Stichele, Robert H; Toubate, Berthine; Veirron, Emilie; Mumcuoglu, Kosta Y

2015-05-01

Head lice infestation is still a public health problem worldwide, with an intracountry and intercountry prevalence variation of 0.7 to 59%. There is a large variety of over-the-counter anti-louse products, but their efficacy is not always well assessed. Our objective was to test the pediculicidal and ovicidal efficacy of 21 over-the-counter head louse products, available in France during the period of 2008 to 2012. We tested children living in Tours City in central France and visiting preschools, primary schools, kindergarten, camps, and child care facilities, as well as children in their family houses, and were examined for the presence of lice. The products were collected from randomly selected pharmacies by covert investigators and then tested in the laboratory on an ex vivo sample of head lice and their eggs, collected from the hair of infested children. Living lice and unharmed eggs were collected from the scalps of 3-12 years old. The laboratory conditions for ex vivo testing mimicked the manufacturers' instructions for exposure time and application method. In 21 runs, 3919 living lice and 4321 undamaged living eggs were collected from the scalp of over 400 children. The 21 products were classified in three groups: 6 products in a group of potentially 100% pediculicidal activity and potentially 100% ovicidal activity, 8 products in a group of potentially 100% pediculicidal activity but insufficient ovicidal activity (including 2 products with claims of single application treatment), and 7 products in a group of insufficient pediculicidal activity and ovicidal activity. The pharmaceutical market for head lice products in France is swamped with poorly tested and ineffective products. Rigorous efficacy testing preregistration and periodic screening and testing of effectiveness in the post-registration period should be endorsed by the health authorities.

A systematic literature review of pediculosis due to head lice in the Pacific Island Countries and Territories: what country specific research on head lice is needed?

PubMed

Speare, Rick; Harrington, Humpress; Canyon, Deon; Massey, Peter D

2014-06-24

Lack of guidelines on control of pediculosis in the Solomon Islands led to a search for relevant evidence on head lice in the Pacific Island Countries and Territories (PICTs). The aim of this search was to systematically evaluate evidence in the peer reviewed literature on pediculosis due to head lice (Pediculus humanus var capitis) in the 22 PICTs from the perspective of its value in informing national guidelines and control strategies. PubMed, Web of Science, CINAHL and Scopus were searched using the terms (pediculosis OR head lice) AND each of the 22 PICTs individually. PRISMA methodology was used. Exclusion criteria were: i) not on topic; ii) publications on pediculosis not relevant to the country of the particular search; iii) in grey literature. Of 24 publications identified, only 5 were included. Four related to treatment and one to epidemiology. None contained information relevant to informing national guidelines. Current local evidence on head lice in the PICTs is minimal and totally inadequate to guide any recommendations for treatment or control. We recommend that local research is required to generate evidence on: i) epidemiology; ii) knowledge, attitudes and practices of health care providers and community members; iii) efficacy of local commercially available pharmaceutical treatments and local customary treatments; iv) acceptability, accessibility and affordability of available treatment strategies; and iv) appropriate control strategies for families, groups and institutions. We also recommend that operational research be done by local researchers based in the PICTs, supported by experienced head lice researchers, using a two way research capacity building model.

Head Lice of Pygmies Reveal the Presence of Relapsing Fever Borreliae in the Republic of Congo

PubMed Central

Amanzougaghene, Nadia; Akiana, Jean; Mongo Ndombe, Géor; Davoust, Bernard; Nsana, Nardiouf Sjelin; Parra, Henri-Joseph; Fenollar, Florence; Raoult, Didier; Mediannikov, Oleg

2016-01-01

Background Head lice, Pediculus humanus capitis, occur in four divergent mitochondrial clades (A, B, C and D), each having particular geographical distributions. Recent studies suggest that head lice, as is the case of body lice, can act as a vector for louse-borne diseases. Therefore, understanding the genetic diversity of lice worldwide is of critical importance to our understanding of the risk of louse-borne diseases. Methodology/Principal Findings Here, we report the results of the first molecular screening of pygmies’ head lice in the Republic of Congo for seven pathogens and an analysis of lice mitochondrial clades. We developed two duplex clade-specific real-time PCRs and identified three major mitochondrial clades: A, C, and D indicating high diversity among the head lice studied. We identified the presence of a dangerous human pathogen, Borrelia recurrentis, the causative agent of relapsing fever, in ten clade A head lice, which was not reported in the Republic of Congo, and B. theileri in one head louse. The results also show widespread infection among head lice with several species of Acinetobacter. A. junii was the most prevalent, followed by A. ursingii, A. baumannii, A. johnsonii, A. schindleri, A. lwoffii, A. nosocomialis and A. towneri. Conclusions/Significance Our study is the first to show the presence of B. recurrentis in African pygmies’ head lice in the Republic of Congo. This study is also the first to report the presence of DNAs of B. theileri and several species of Acinetobacter in human head lice. Further studies are needed to determine whether the head lice can transmit these pathogenic bacteria from person to another. PMID:27911894

RNA Interference of NADPH-Cytochrome P450 Reductase Results in Reduced Insecticide Resistance in the Bed Bug, Cimex lectularius

PubMed Central

Zhu, Fang; Sams, Sarah; Moural, Tim; Haynes, Kenneth F.; Potter, Michael F.; Palli, Subba R.

2012-01-01

Background NADPH-cytochrome P450 reductase (CPR) plays a central role in cytochrome P450 action. The genes coding for P450s are not yet fully identified in the bed bug, Cimex lectularius. Hence, we decided to clone cDNA and knockdown the expression of the gene coding for CPR which is suggested to be required for the function of all P450s to determine whether or not P450s are involved in resistance of bed bugs to insecticides. Methodology/Principal Findings The full length Cimex lectularius CPR (ClCPR) cDNA was isolated from a deltamethrin resistant bed bug population (CIN-1) using a combined PCR strategy. Bioinformatics and in silico modeling were employed to identify three conserved binding domains (FMN, FAD, NADP), a FAD binding motif, and the catalytic residues. The critical amino acids involved in FMN, FAD, NADP binding and their putative functions were also analyzed. No signal peptide but a membrane anchor domain with 21 amino acids which facilitates the localization of ClCPR on the endoplasmic reticulum was identified in ClCPR protein. Phylogenetic analysis showed that ClCPR is closer to the CPR from the body louse, Pediculus humanus corporis than to the CPRs from the other insect species studied. The ClCPR gene was ubiquitously expressed in all tissues tested but showed an increase in expression as immature stages develop into adults. We exploited the traumatic insemination mechanism of bed bugs to inject dsRNA and successfully knockdown the expression of the gene coding for ClCPR. Suppression of the ClCPR expression increased susceptibility to deltamethrin in resistant populations but not in the susceptible population of bed bugs. Conclusions/Significance These data suggest that P450-mediated metabolic detoxification may serve as one of the resistance mechanisms in bed bugs. PMID:22347424

RNA interference of NADPH-cytochrome P450 reductase results in reduced insecticide resistance in the bed bug, Cimex lectularius.

PubMed

Zhu, Fang; Sams, Sarah; Moural, Tim; Haynes, Kenneth F; Potter, Michael F; Palli, Subba R

2012-01-01

NADPH-cytochrome P450 reductase (CPR) plays a central role in cytochrome P450 action. The genes coding for P450s are not yet fully identified in the bed bug, Cimex lectularius. Hence, we decided to clone cDNA and knockdown the expression of the gene coding for CPR which is suggested to be required for the function of all P450s to determine whether or not P450s are involved in resistance of bed bugs to insecticides. The full length Cimex lectularius CPR (ClCPR) cDNA was isolated from a deltamethrin resistant bed bug population (CIN-1) using a combined PCR strategy. Bioinformatics and in silico modeling were employed to identify three conserved binding domains (FMN, FAD, NADP), a FAD binding motif, and the catalytic residues. The critical amino acids involved in FMN, FAD, NADP binding and their putative functions were also analyzed. No signal peptide but a membrane anchor domain with 21 amino acids which facilitates the localization of ClCPR on the endoplasmic reticulum was identified in ClCPR protein. Phylogenetic analysis showed that ClCPR is closer to the CPR from the body louse, Pediculus humanus corporis than to the CPRs from the other insect species studied. The ClCPR gene was ubiquitously expressed in all tissues tested but showed an increase in expression as immature stages develop into adults. We exploited the traumatic insemination mechanism of bed bugs to inject dsRNA and successfully knockdown the expression of the gene coding for ClCPR. Suppression of the ClCPR expression increased susceptibility to deltamethrin in resistant populations but not in the susceptible population of bed bugs. These data suggest that P450-mediated metabolic detoxification may serve as one of the resistance mechanisms in bed bugs.

Chemical composition and efficacy of some selected plant oils against Pediculus humanus capitis in vitro.

PubMed

Yones, Doaa A; Bakir, Hanaa Y; Bayoumi, Soad A L

2016-08-01

Natural compounds have been suggested as alternative sources for pediculosis capitis control. We aimed to investigate the chemical composition and evaluate the pediculicidal activity of spearmint, clove, cassia, thyme, eucalyptus, and anise essential oils in addition to sesame oil against human head lice in vitro. A filter paper contact bioassay method was used by applying 0.25 and 0.5 mg/cm(2) of each tested oil to filter paper in Petri dishes with 15 females head lice and another with ten nits. The lice mortalities were reported every 5 min for 180 min. The percentage of inhibition of hatch (PIH) was used to calculate ovicidal activity by daily microscopic inspections 5 days after the hatching of controls. Comparison with the widely used pediculicide (malathion) was performed. The most effective essential oil was spearmint followed by cassia and clove with KT50 values of 4.06, 7.62, and 12.12 at 0.5 mg/cm(2) and 8.84, 11.38, and 19.73 at 0.25 mg/cm(2), respectively. Thyme, eucalyptus, and anise were also effective adulticides with KT50 values of 18.61, 32.65, and 37.34 at 0.5 mg/cm(2) and 29.92, 43.16, and 45.37 at 0.25 mg/cm(2), respectively. Essential oils were also successful in inhibiting nymph emergence. Spearmint oil was the most effective, with a complete inhibition of emergence at 0.5 mg/cm(2). Sesame fixed oil did not show any adulticidal or ovicidal activity against head lice in vitro. The observed insecticidal activity was comparable to malathion. The results herein described the effectiveness of these essential oils as potential pediculicides for head lice control. Incorporation of essential oils in pediculicide formulations needs proper formulation and clinical trials.

A highly efficacious pediculicide based on dimeticone: Randomized observer blinded comparative trial

PubMed Central

Heukelbach, Jorg; Pilger, Daniel; Oliveira, Fabíola A; Khakban, Adak; Ariza, Liana; Feldmeier, Hermann

2008-01-01

Background Infestation with the human head louse (Pediculus humanus capitis) occurs worldwide. Existing treatment options are limited, and reports of resistance to commonly used pediculicides have been increasing. In this trial we assessed the efficacy of a product containing a high (92%) concentration of the silicone oil dimeticone (identical in composition to NYDA®), as compared to a 1% permethrin lotion. Methods Randomized, controlled, observer blinded clinical trial. Participants were recruited from a poor urban neighbourhood in Brazil where pediculosis capitis was highly prevalent. To minimize reinfestation during the trial, participants (145 children aged 5–15 years with head lice infestations) were transferred to a holiday resort outside the endemic area for a period of 9 days. Two applications of dimeticone or 1% permethrin were done, seven days apart. Outcome measures were defined as cure (absence of vital head lice) after first application and before and after second applications, degree of itching, cosmetic acceptability, and clinical pathology. Results Overall cure rates were: day 2 – dimeticone 94.5% (95% CI: 86.6% – 98.5%) and permethrin 66.7% (95% CI: 54.6% – 77.3%; p < 0.0001); day 7 – dimeticone 64.4% (95% CI: 53.3% – 75.3%) and permethrin 59.7% (95% CI: 47.5% – 71.1%; p = 0.5); day 9 – dimeticone 97.2% (95% CI: 90.3% – 99.7%) and permethrin 67.6% (95% CI: 55.4%-78.2%); p < 0.0001). Itching was reduced similarly in both groups. Cosmetic acceptability was significantly better in the dimeticone group as compared to the permethrin group (p = 0.01). Two mild product-related incidents occurred in the dimeticone group. Conclusion The dimeticone product is a safe and highly efficacious pediculicide. Due to its physical mode of action (interruption of the lice's oxygen supply of the central nervous system), development of resistance is unlikely. Trial registration Current Controlled Trials ISRCTN15117709. PMID:18783606

Evidence That Head and Body Lice on Homeless Persons Have the Same Genotype

PubMed Central

Veracx, Aurélie; Rivet, Romain; McCoy, Karen D.; Brouqui, Philippe; Raoult, Didier

2012-01-01

Human head lice and body lice are morphologically and biologically similar but have distinct ecologies. They were shown to have almost the same basic genetic content (one gene is absent in head lice), but differentially express certain genes, presumably responsible for the vector competence. They are now believed to be ecotypes of the same species (Pediculus humanus) and based on mitochondrial studies, body lice have been included with head lice in one of three clades of human head lice (Clade A). Here, we tested whether head and body lice collected from the same host belong to the same population by examining highly polymorphic intergenic spacers. This study was performed on lice collected from five homeless persons living in the same shelter in which Clade A lice are prevalent. Lice were individually genotyped at four spacer loci. The genetic identity and diversity of lice from head and body populations were compared for each homeless person. Population genetic structure was tested between lice from the two body regions and between the lice from different host individuals. We found two pairs of head and body lice on the same homeless person with identical multi locus genotypes. No difference in genetic diversity was found between head and body louse populations and no evidence of significant structure between the louse populations was found, even after controlling for a possible effect of the host individual. More surprisingly, no structure was obvious between lice of different homeless persons. We believe that the head and body lice collected from our five subjects belong to the same population and are shared between people living in the same shelter. These findings confirm that head and body lice are two ecotypes of the same species and show the importance of implementing measures to prevent lice transmission between homeless people in shelters. PMID:23049889

Effect of a health education program on reduction of pediculosis in school girls at Amphoe Muang, Khon Kaen Province, Thailand.

PubMed

Yingklang, Manachai; Sengthong, Chatchawan; Haonon, Ornuma; Dangtakot, Rungtiwa; Pinlaor, Porntip; Sota, Chulaporn; Pinlaor, Somchai

2018-01-01

Pediculosis caused by head lice (Pediculus humanus capitis) infestation is still an important health problem in schoolchildren, especially girls, worldwide, including in Thailand. Although pediculicidal agents effectively kill head lice, the re-infestation rate is still high. Thus, prevention is an important strategy for any sustainable control program. We aimed to develop and evaluate the efficacy of a health education program for increasing knowledge, changing attitudes and promoting preventive practices to reduce prevalence of pediculosis among school girls in Amphoe Muang, Khon Kaen, northeastern Thailand. Six schools were selected using multistage simple randomization and were allocated into intervention or control groups. A total of 267 girls was enrolled from these schools. A "knowledge, attitude and practice" (KAP) questionnaire, consent forms and health education materials were constructed and tested by experts and in one pilot school before the main investigation. Baseline prevalence of adult lice and nits was determined. The health education package was given only to the intervention group. The KAP questionnaire was re-evaluated at two months after intervention. At baseline, the prevalence and intensity of head lice infestation, and the KAP scores did not differ significantly between the two groups. After re-evaluation at two months, the KAP score was significantly greater in the intervention group. A significant decrease of the infestation rate from 59% to 44% was observed in the intervention group, whereas infestation increased in the control group (from 56% to 65%). The incidence of new cases in the intervention group (6.14%) was lower than in the control group (12.62%). These findings indicated that the newly-established health education package is an effective tool for increasing KAP and reducing head lice infestation in school girls. Efforts to combat pediculosis in schoolchildren elsewhere may consider including this, or a similar, health education package in their programs.

Evidence that head and body lice on homeless persons have the same genotype.

PubMed

Veracx, Aurélie; Rivet, Romain; McCoy, Karen D; Brouqui, Philippe; Raoult, Didier

2012-01-01

Human head lice and body lice are morphologically and biologically similar but have distinct ecologies. They were shown to have almost the same basic genetic content (one gene is absent in head lice), but differentially express certain genes, presumably responsible for the vector competence. They are now believed to be ecotypes of the same species (Pediculus humanus) and based on mitochondrial studies, body lice have been included with head lice in one of three clades of human head lice (Clade A). Here, we tested whether head and body lice collected from the same host belong to the same population by examining highly polymorphic intergenic spacers. This study was performed on lice collected from five homeless persons living in the same shelter in which Clade A lice are prevalent. Lice were individually genotyped at four spacer loci. The genetic identity and diversity of lice from head and body populations were compared for each homeless person. Population genetic structure was tested between lice from the two body regions and between the lice from different host individuals.We found two pairs of head and body lice on the same homeless person with identical multi locus genotypes. No difference in genetic diversity was found between head and body louse populations and no evidence of significant structure between the louse populations was found, even after controlling for a possible effect of the host individual. More surprisingly, no structure was obvious between lice of different homeless persons.We believe that the head and body lice collected from our five subjects belong to the same population and are shared between people living in the same shelter. These findings confirm that head and body lice are two ecotypes of the same species and show the importance of implementing measures to prevent lice transmission between homeless people in shelters.

Severe pediculosis capitus: a case of "crusted lice" with autoeczematization.

PubMed

Connor, Cody J; Selby, John C; Wanat, Karolyn A

2016-03-16

Pediculosis humanus capitus infestations are common and classically present with intense pruritus of the scalp. Although many treatment options are available, lice are becoming more resistant to conventional therapies and severe clinical presentations are bound to become more prevalent. We present a case of treatment-resistant pediculosis capitus resulting in diffuse autoeczematization of the torso and extremities and severe crusting and scaling of the scalp, which we called "crusted lice." This eruption differs from the well-described id reaction known as "pediculid" and represents a more dramatic manifestation of rampant infestation. This paper provides an up-to-date review of treatment options available for pediculosis humanus capitus, including newer medications like the ones that eventually led to resolution of our patient's extreme infestation.

Human-use antibacterial residues in the natural environment of China: implication for ecopharmacovigilance.

PubMed

Wang, Jun; He, Bingshu; Hu, Xiamin

2015-06-01

Antibacterial residues in the natural environment have been of increasing concern due to their impact on bacteria resistance development and toxicity to natural communities and ultimately to public health. China is a large country with high production and consumption of antibacterials for its population growth and economic development in recent years. In this article, we summarized the current situation of human-use antibacterial pollution in Chinese water (wastewaters, natural and drinking waters) and solid matrices (sludge, sediment, and soil) reported in 33 peer-reviewed papers. We found that, although there are adequate wastewater treatment systems in China, human-use antibacterial residues in the natural environment were reported almost throughout the whole country. Three most frequently prescribed classes of antibacterials in China, including quinolones, macrolides, and β-lactam, were also the predominant classes of residues in Chinese environment, manifested as the high concentration and detection frequency. In view of this alarming situation, we have presented that ecopharmacovigilance (EPV) might be implemented in the antibacterial drug administration of China, as the active participation of the pharmaceutical industry and drug regulatory authorities from the diffuse source of antibacterial pollution. Considering EPV experience of developed countries together with the actual conditions of China, we have identified some approaches that can be taken, including:• Focus on education;• Further strengthening and persevering the antibacterial stewardship strategies and pharmaceutical take-back programs in China;• Designing greener antibacterials with better degradability in the environment;• Implementing environmental risk assessment prior to launch of new drugs;• Strengthening collaboration in EPV-related areas.

Epitope-focused peptide immunogens in human use adjuvants protect rabbits from experimental inhalation anthrax.

PubMed

Oscherwitz, Jon; Feldman, Daniel; Yu, Fen; Cease, Kemp B

2015-01-09

Anthrax represents a formidable bioterrorism threat for which new, optimized vaccines are required. We previously demonstrated that epitope-focused multiple antigenic peptides or a recombinant protein in Freund's adjuvant can elicit Ab against the loop neutralizing determinant (LND), a cryptic linear neutralizing epitope in the 2ß2-2ß3 loop of protective antigen from Bacillus anthracis, which mediated protection of rabbits from inhalation challenge with B. anthracis Ames strain. However, demonstration of efficacy using human-use adjuvants is required before proceeding with further development of an LND vaccine for testing in non-human primates and humans. To optimize the LND immunogen, we first evaluated the protective efficacy and immune correlates associated with immunization of rabbits with mixtures containing two molecular variants of multiple antigenic peptides in Freunds adjuvant, termed BT-LND(2) and TB-LND(2). TB-LND(2) was then further evaluated for protective efficacy in rabbits employing human-use adjuvants. Immunization of rabbits with TB-LND(2) in human-use adjuvants elicited protection from Ames strain spore challenge which was statistically indistinguishable from that elicited through immunization with protective antigen. All TB-LND(2) rabbits with any detectable serum neutralization prior to challenge were protected from aerosolized spore exposure. Remarkably, rabbits immunized with TB-LND(2) in Alhydrogel/CpG had significant anamnestic increases in post-challenge LND-specific Ab and neutralization titers despite little evidence of spore germination in these rabbits. An LND-specific epitope-focused vaccine may complement PA-based vaccines and may represent a complementary stand-alone vaccine for anthrax. Copyright © 2014 Elsevier Ltd. All rights reserved.

Human phthiriasis. Can dermoscopy really help dermatologists? Entodermoscopy: a new dermatological discipline on the edge of entomology.

PubMed

Scanni, G

2012-02-01

The diagnosis of human phtiriasis (often referred to as the "crab" or the "pubic louse") can be more difficult than other types of pediculosis (Pediculus corporis and Pediculus capitis) because this insect has a smaller body of 1.2 x 0.8 mm, may be lighter in color, not as mobile and therefore harder to see to the naked eye. Can dermoscopy aid to perform a better analysis of the skin? The clinical experience developed in two patients gives an affirmative answer, moreover adding useful information of insect and its eggs already known to entomologists but never used in dermatological diagnosis. The identification in vivo can distinguish Phthirus pubis from other skin signs while the conical shape of the operculum and the wide fixing sleeve of egg to hair, tells what species of louse is infesting, even if the insect is unavailable or nits are elsewhere from the pubic area. Entodermoscopy, provided that dermatologists have some knowledge of entomology, therefore promises advantages over standard microscopic examination.

Efficacy of herbal shampoo base on native plant against head lice (Pediculus humanus capitis De Geer, Pediculidae: Phthiraptera) in vitro and in vivo in Thailand.

PubMed

Soonwera, Mayura

2014-09-01

Head lice infestation (or pediculosis) is an important public health problem in Thailand, especially in children between the ages 5 and 11 years. Head lice resistance is increasing, chemical pediculicides have lost their efficacy, and, therefore, alternative pediculicides such as herbal shampoos have been proposed to treat head lice infestation. Thus, the present study investigated the efficacy of three herbal shampoos based on native plants in Thailand (Acorus calamus Linn., Phyllanthus emblica Linn., and Zanthoxylum limonella Alston) against head lice and compared them with carbaryl shampoo (Hafif shampoo, 0.6% w/v carbaryl), malathion shampoo (A-Lice shampoo, 1.0% w/v malathion), and commercial shampoos (Babi Mild Natural' N Mild and Johnson's baby shampoo) in order to assess their in vitro and in vivo efficacy. For in vitro study, doses of 0.12 and 0.25 ml/cm(2) of each herbal shampoo were applied to filter paper, then 10 head lice were place on the filter paper. The mortalities of head lice were recorded at 5, 15, 30, and 60 min. The results revealed that all herbal shampoo were more effective on pediculicidal activity than chemical and commercial shampoos with 100% mortality at 15 min; LT₅₀ values ranged from 0.25 to 1.90 min. Meanwhile, chemical shampoos caused 20-80% mortality, and LT₅₀ values ranged from 6.50 to 85.43 min. On the other side, commercial shampoos showed 4.0% mortality. The most effective pediculicide was Z. limonella shampoo, followed by A. calamus shampoo, P. emblica shampoo, carbaryl shampoo, malathion shampoo, and commercial shampoo, respectively. In vivo results showed that all herbal shampoos were also more effective for head lice treatment than chemical and commercial shampoos with 94.67-97.68% of cure rate after the first treatment; the second treatment, 7 days later, revealed that the cure rate was 100%. Meanwhile, chemical shampoo showed 71.67-93.0% of cure rate and, unfortunately, commercial shampoos were nontoxic to head lice and showed 0% of cure rate after the first and the second treatments. Our data showed that three herbal shampoos of native plants in Thailand in this study are suitable to be used as pediculicides for Thai children since it is safe for children and there is no side-effect after application.

Spotted in the News: Using Media Reports to Examine Leopard Distribution, Depredation, and Management Practices outside Protected Areas in Southern India

PubMed Central

Athreya, Vidya; Srivathsa, Arjun; Puri, Mahi; Karanth, Krithi K.; Kumar, N. Samba; Karanth, K. Ullas

2015-01-01

There is increasing evidence of large carnivore presence outside protected areas, globally. Although this spells conservation success through population recoveries, it makes carnivore persistence in human-use landscapes tenuous. The widespread distribution of leopards in certain regions of India typifies this problem. We obtained information on leopard-human interactions at a regional scale in Karnataka State, India, based on systematic surveys of local media reports. We applied an innovative occupancy modelling approach to map their distribution patterns and identify hotspots of livestock/human depredation. We also evaluated management responses like removals of ‘problem’ leopards through capture and translocations. Leopards occupied around 84,000 km2 or 47% of the State’s geographic area, outside designated national parks and wildlife sanctuaries. Their presence was facilitated by extent of vegetative cover- including irrigated croplands, rocky escarpments, and prey base in the form of feral and free-ranging dogs. Higher probabilities of livestock/human attacks by leopards were associated with similar ecological features as well as with capture/removals of leopards. Of the 56 cases of leopard removals reported, 91% did not involve human attacks, but followed livestock predation or only leopard sightings. The lack of knowledge on leopard ecology in human-use areas has resulted in unscientific interventions, which could aggravate the problem rather than mitigating it. Our results establish the presence of resident, breeding leopards in human-use areas. We therefore propose a shift in management focus, from current reactive practices like removal and translocation of leopards, to proactive measures that ensure safety of human lives and livelihoods. PMID:26556229

Development of an Analytical Method to Extract and Detect Pharmaceuticals in Plant Matrices

EPA Science Inventory

It has been shown that human-use macrolide antibiotics (azithromycin, clindamycin, and roxithromycin) are environmentally available in wastewaters, source waters, and biosolids. Since some water authorities use the treated wastewater effluent for non-potable water reuse such as f...

On Man and Ecosystems.

ERIC Educational Resources Information Center

Brookfield, Harold

1982-01-01

Distinctions between natural ecosystems and human ecosystems are misleading. Natural and social sciences can be integrated through the concept of a "human-use ecosystem," in which social scientists analyze the community, household, and individual, and natural scientists analyze the land. Includes a case study of St. Kitts. (KC)

CHEMICAL MARKERS OF HUMAN WASTE CONTAMINATION IN SOURCE WATERS: A SIMPLIFIED ANALYTICAL APPROACH

EPA Science Inventory

Giving public water authorities a tool to monitor and measure levels of human waste contamination of waters simply and rapidly would enhance public protection. This methodology, using both urobilin and azithromycin (or any other human-use pharmaceutical) could be used to give pub...

A CASE STUDY: CROP (LETTUCE, SPINACH, AND CARROTS) UPTAKE OF THREE MACROLIDE ANTIBIOTICS (AZITHROMYCIN, CLINDAMYCIN AND ROXITHROMYCIN) AND OTHER DRUGS

EPA Science Inventory

It has been shown that human-use macrolide antibiotics (azithromycin, clindamycin, and roxithromycin) are environmentally available in wastewaters, source waters, and biosolids. In order to better understand the fate of these compounds into food crops via root migration, we condu...

Efficacy of a grapefruit extract on head lice: a clinical trial.

PubMed

Abdel-Ghaffar, Fathy; Semmler, Margit; Al-Rasheid, Khaled; Klimpel, Sven; Mehlhorn, Heinz

2010-01-01

Twenty children aging 2-9 years old--four boys with short hair and 16 girls with long hair--were included in a clinical test on the efficacy of a product against head lice (Pediculus humanus capitis). Their hair were exposed to Licatack, which is a recently developed new anti-louse medicinal product containing extracts of grapefruits besides high quality shampoo components. Prior to this field trial, the product Licatack was tested dermatologically to be skin safe receiving the grade "very good". The children's mothers combed the kids prior to the start of the test in order to confirm that they were all lice-infested. The obtained lice were used for in vitro tests. All children were heavily infested. After combing and preservation of the living lice, the hair was wet with tap water. Then, 50 ml of the Licatack shampoo was placed onto the top of each child's head. Then, the mothers distributed the rather fluid product all over the hair thoroughly from their base at the skin until the free end. During this process, a type of massage, the product became foamy and it was easily recognized where the product covered the hair, thus, avoiding untreated spots. The hair of half of the treated children were washed with tap water after 10 min of exposition; while in the other half of the children, the exposition period was prolonged to 20 min before washing. When combing the kids with a metal louse comb after the washing, the lice were found immobile and they did not recover during the following observation period of 4 h. Only two lice from the group with an exposition time of only 10 min showed some slight leg movements after they had been combed off, but they died within the next 2 h. Thus, this new anti-louse medicinal product has a very quick and efficient activity besides its advantages of being non-inflammable, skin safe, and nice smelling. None of the kids claimed any burning at the skin or other side effects, although the skin showed, prior to treatment, lots of scars due to louse bites. The dead lice always appeared considerably shrunken due to drying. The second treatment after 10 days revealed a few dead larval stages since, apparently, some larvae (apparently treated at an early stage of development when treated) had hatched from the extremely numerous nits in the period between first and second treatment. Experiments with cutoff nits, however, showed that the product also kills larval stages inside nits.

Detection of bacterial pathogens in clade E head lice collected from Niger's refugees in Algeria.

PubMed

Louni, Meriem; Amanzougaghene, Nadia; Mana, Nassima; Fenollar, Florence; Raoult, Didier; Bitam, Idir; Mediannikov, Oleg

2018-06-15

Head lice, Pediculus humanus capitis, are obligate blood-sucking parasites. Phylogenetically, they occur in five divergent mitochondrial clades (A, D, B, C and E), each having a particular geographical distribution. Recent studies have revealed that head lice, as is the case of body lice, can act as a vector for louse-borne diseases. Here, we aimed to study the genetic diversity of head lice collected from Niger's refugees (migrant population) arriving in Algeria, northern Africa, and to look for louse-borne pathogens. Comparative head lice samples collected from indigenous population of schoolchildren (non-immigrant) were also analyzed to frame the study. In this study, 37 head lice samples were collected from 31 Nigerien refugees, as well as 45 head lice from 27 schoolchildren. The collection was established in three localities of eastern Algiers, north Algeria. Quantitative real-time PCR screening of pathogens bacteria and the genetic characterisation of the head lice satut were performed. Through amplification and sequencing of the cytb gene, results showed that all head lice of Nigerien refugees 37/82 (45.12%) belonged to clade E with the presence of four new haplotypes, while, of the 45 head lice of schoolchildren, 34/82 lice (41.46%) belonged to clade A and 11/82 (13.41%) belonged to clade B. Our study is the first to report the existence of clade E haplogroup in Nigerien head lice. DNA of Coxiella burnetii was detected in 3/37 (8.10%) of the head lice collected from 3 of the 31 (9.67%) migrant population. We also revealed the presence of Acinetobacter DNA in 20/37 (54.05%) of head lice collected from 25/31 (80.64%) of the Nigerien refugees, and in 25/45 (55.55%) head lice collected from 15/27 (55.55%) schoolchildren. All positive Nigerien-head lice for Acinetobacter spp. were identified as A. baumannii, while positive schoolchildren-head lice were identified as A. johnsonii 15/25 (60%), A. variabilis 8/25 (32%) and A. baumannii 2/25 (8%). Based on these findings from head lice collected on migrant and non-migrant population, our results show, for the first time, that head lice from Niger belong to haplogroup E, and confirm that the clade E had a west African distribution. We also detected, for the first time, the presence of C. burnetii and A. baumannii in these Nigerien head lice. Nevertheless, further studies are needed to determine whether the head lice can transmit these pathogenic bacteria from one person to another.

Pair of lice lost or parasites regained: the evolutionary history of anthropoid primate lice

PubMed Central

Reed, David L; Light, Jessica E; Allen, Julie M; Kirchman, Jeremy J

2007-01-01

Background The parasitic sucking lice of primates are known to have undergone at least 25 million years of coevolution with their hosts. For example, chimpanzee lice and human head/body lice last shared a common ancestor roughly six million years ago, a divergence that is contemporaneous with their hosts. In an assemblage where lice are often highly host specific, humans host two different genera of lice, one that is shared with chimpanzees and another that is shared with gorillas. In this study, we reconstruct the evolutionary history of primate lice and infer the historical events that explain the current distribution of these lice on their primate hosts. Results Phylogenetic and cophylogenetic analyses suggest that the louse genera Pediculus and Pthirus are each monophyletic, and are sister taxa to one another. The age of the most recent common ancestor of the two Pediculus species studied matches the age predicted by host divergence (ca. 6 million years), whereas the age of the ancestor of Pthirus does not. The two species of Pthirus (Pthirus gorillae and Pthirus pubis) last shared a common ancestor ca. 3–4 million years ago, which is considerably younger than the divergence between their hosts (gorillas and humans, respectively), of approximately 7 million years ago. Conclusion Reconciliation analysis determines that there are two alternative explanations that account for the current distribution of anthropoid primate lice. The more parsimonious of the two solutions suggests that a Pthirus species switched from gorillas to humans. This analysis assumes that the divergence between Pediculus and Pthirus was contemporaneous with the split (i.e., a node of cospeciation) between gorillas and the lineage leading to chimpanzees and humans. Divergence date estimates, however, show that the nodes in the host and parasite trees are not contemporaneous. Rather, the shared coevolutionary history of the anthropoid primates and their lice contains a mixture of evolutionary events including cospeciation, parasite duplication, parasite extinction, and host switching. Based on these data, the coevolutionary history of primates and their lice has been anything but parsimonious. PMID:17343749

Teamharmony: Employing Matchmaking Algorithms to Team-Building

DTIC Science & Technology

2017-12-01

Army1 A. HUMAN CHEMISTRY Within groups of people , there exists the powerful social phenomenon known as human chemistry. Although many definitions...which occur when two or more people interact, and cause the resulting relationship to be positively cohesive or toxic. Much like the weather, human...use experiential intuition when staffing teams. Apart from SOF units, there are no systems in place to gauge psychological makeup. Figure 2

Climate, rain shadow, and human-use influences on fire regimes in the eastern Sierra Nevada, California, USA

Treesearch

M.P. North; K.M. van de Water; S.L. Stephens; B.M. Collins

2009-01-01

There have been few fire history studies of eastern Sierra Nevada forests in California, USA, where a steep elevation gradient, rain shadow conditions, and forest stand isolation may produce different fire regimes than those found on the range’s western slope. We investigated historic fire regimes and potential climate influences on four forest types ranging in...

[Human pediculosis, or how to treat lice infestations?].

PubMed

García Sanchón, Carlos

2004-05-01

The author reports on relevant aspects of pediculosis humanus, citing the lice species implicated, their location in the zones affected by lice infestations on human bodies and in their clothing; furthermore, he describes the most frequent lesions produced by lice, the adequate handling of lice infestations and their treatment. Lice are not a recent phenomenon; probably the lice which we encounter today acting as a parasite on humans is very similar to lice which infested humans centuries ago.

The Effect of Aircrew Age on +Gz Tolerance as Measured in a Human-Use Centrifuge

DTIC Science & Technology

2000-08-01

acceleration stress (+Gz). This type of acceleration displaces blood in the head to foot direction. As the pressure in the vessels of the lower body... blood in the lower extremities translates into reduced cardiac output provoking the cardiovascular system, mainly by the activation of baroreceptor ...This pressure aids the cardiovascular system to maintain adequate blood flow to the CNS by forcing blood towards the head "counteracting" the effect of

CHEMICAL MARKERS OF HUMAN WASTE ...

EPA Pesticide Factsheets

Giving public water authorities another tool to monitor and measure levels of human waste contamination of waters simply and rapidly would enhance public protection. Most of the methods used today detect such contamination by quantifying microbes occurring in feces in high enough densities that they can be measured easily. However, most of these microbes, for example E. coli, do not serve as specific markers for any one host species and many can have origins other than feces. As an alternative, chemicals shed in feces and urine might be used to detect human waste contamination of environmental waters. One potential chemical marker of human waste is the compound urobilin. Urobilin is one of the final by-products of hemoglobin breakdown. Urobilin is excreted in both the urine and feces from many mammals, particularly humans. Source waters from 21 sites in New England, Nevada, and Michigan were extracted using hydrophilic-lipophilic balance (HLB) cartridges and then analyzed by high performance liquid chromatography-electrospray-mass spectrometry (HPLC-ES-MS). As a marker of human waste, urobilin was detected in many of the source waters at concentrations ranging from not detectable to 300 ng/L. Besides urobilin, zithromycin, an antibiotic widely prescribed for human-use only in the US, was also detected in many of these waters, with concentrations ranging from not detectable to 77 ng/L. This methodology, using both urobilin and azithromycin (or any other human-use

[Pediculus capitis in schoolchildren of the urban area of Nuevo León, México: Analyses of associated factors].

PubMed

Molina-Garza, Zinnia J; Galaviz-Silva, Lucio

2017-09-01

Pediculosis capitis is a recurring problem affecting 6 to 12 millions of children annually; there are no epidemiological data on this subject in the state of Nuevo León, and there are few in México. Therefore, new contributions are needed to design control strategies based on factors that may predispose to head lice infestation. To determine the prevalence of Pediculus capitis in primary school children and to evaluate risk factors and individual or socioeconomic characteristics statistically associated with infestation. We included 840 schoolchildren from six municipalities after parents and children signed an informed consent. Ectoparasites were collected from infested children using a finetoothed comb. Participants were interviewed using a questionnaire on individual and socioeconomic variables including age, gender, education, hair characteristics, overcrowding, and siblings with pediculosis, among others. The overall prevalence of head lice in schoolchildren was 28% (235/840), the highest prevalence was among girls (33.7%, 140/417), and children from the fifth grade (10-11 years old) were the most affected (6.2%; 52/840). Female gender, long hair and the father's education level were significantly associated with P. capitis. Our results showed that the P. capitis prevalence in Nuevo León is one of the highest in Mexico, that it constitutes a real public health problem, and that there is need to establish prevention programs at home and school to decrease or to control P. capitis with the support of public health authorities.

Epidural Anesthesia: New Computer Technology Used to Enhance the Teaching of a Common Anesthetic Procedure

DTIC Science & Technology

1997-10-01

proper didactic courses as well. Bony Anatomy Anatomy was learned through the works of Galen, a Greco-Roman physician. Vesalius, a great author and...dimensional objects that can be visualized from all angles. Significance of Study The creation of cyber teaching tools that are based on tme human...use of the Visible Human ™ Datasets in the nursing literature. This new tool will be capable of teaching the anatomy of a specific region of the human

Human habitat positioning system for NASA's space flight environmental simulator

NASA Technical Reports Server (NTRS)

Caldwell, W. F.; Tucker, J.; Keas, P.

1998-01-01

Artificial gravity by centrifugation offers an effective countermeasure to the physiologic deconditioning of chronic exposure to microgravity; however, the system requirements of rotational velocity, radius of rotation, and resultant centrifugal acceleration require thorough investigation to ascertain the ideal human-use centrifuge configuration. NASA's Space Flight Environmental Simulator (SFES), a 16-meter (52-foot) diameter, animal-use centrifuge, was recently modified to accommodate human occupancy. This paper describes the SFES Human Habitat Positioning System, the mechanism that facilitates radius of rotation variability and alignment of the centrifuge occupants with the artificial gravity vector.

Wet combing for the eradication of head lice.

PubMed

2013-03-01

Manual removal (using conditioner and comb or a wet comb) can be used in the treatment of head lice. Head lice infestation (Pediculosis humanus capitis) is a common problem. It is diagnosed by visualising the lice. As half of people infested with head lice will not scratch, all people in contact with a person affected with head lice should be manually checked for infestations. Wet combing is easily and safely performed at home, but persistence is needed. This article describes the process of head lice removal using a wet comb. It has NHMRC Level 2 evidence of efficacy and no serious adverse effects have been reported.

Mitochondrial genome deletions and minicircles are common in lice (Insecta: Phthiraptera)

PubMed Central

2011-01-01

Background The gene composition, gene order and structure of the mitochondrial genome are remarkably stable across bilaterian animals. Lice (Insecta: Phthiraptera) are a major exception to this genomic stability in that the canonical single chromosome with 37 genes found in almost all other bilaterians has been lost in multiple lineages in favour of multiple, minicircular chromosomes with less than 37 genes on each chromosome. Results Minicircular mt genomes are found in six of the ten louse species examined to date and three types of minicircles were identified: heteroplasmic minicircles which coexist with full sized mt genomes (type 1); multigene chromosomes with short, simple control regions, we infer that the genome consists of several such chromosomes (type 2); and multiple, single to three gene chromosomes with large, complex control regions (type 3). Mapping minicircle types onto a phylogenetic tree of lice fails to show a pattern of their occurrence consistent with an evolutionary series of minicircle types. Analysis of the nuclear-encoded, mitochondrially-targetted genes inferred from the body louse, Pediculus, suggests that the loss of mitochondrial single-stranded binding protein (mtSSB) may be responsible for the presence of minicircles in at least species with the most derived type 3 minicircles (Pediculus, Damalinia). Conclusions Minicircular mt genomes are common in lice and appear to have arisen multiple times within the group. Life history adaptive explanations which attribute minicircular mt genomes in lice to the adoption of blood-feeding in the Anoplura are not supported by this expanded data set as minicircles are found in multiple non-blood feeding louse groups but are not found in the blood-feeding genus Heterodoxus. In contrast, a mechanist explanation based on the loss of mtSSB suggests that minicircles may be selectively favoured due to the incapacity of the mt replisome to synthesize long replicative products without mtSSB and thus the loss of this gene lead to the formation of minicircles in lice. PMID:21813020

Mitochondrial genome deletions and minicircles are common in lice (Insecta: Phthiraptera).

PubMed

Cameron, Stephen L; Yoshizawa, Kazunori; Mizukoshi, Atsushi; Whiting, Michael F; Johnson, Kevin P

2011-08-04

The gene composition, gene order and structure of the mitochondrial genome are remarkably stable across bilaterian animals. Lice (Insecta: Phthiraptera) are a major exception to this genomic stability in that the canonical single chromosome with 37 genes found in almost all other bilaterians has been lost in multiple lineages in favour of multiple, minicircular chromosomes with less than 37 genes on each chromosome. Minicircular mt genomes are found in six of the ten louse species examined to date and three types of minicircles were identified: heteroplasmic minicircles which coexist with full sized mt genomes (type 1); multigene chromosomes with short, simple control regions, we infer that the genome consists of several such chromosomes (type 2); and multiple, single to three gene chromosomes with large, complex control regions (type 3). Mapping minicircle types onto a phylogenetic tree of lice fails to show a pattern of their occurrence consistent with an evolutionary series of minicircle types. Analysis of the nuclear-encoded, mitochondrially-targetted genes inferred from the body louse, Pediculus, suggests that the loss of mitochondrial single-stranded binding protein (mtSSB) may be responsible for the presence of minicircles in at least species with the most derived type 3 minicircles (Pediculus, Damalinia). Minicircular mt genomes are common in lice and appear to have arisen multiple times within the group. Life history adaptive explanations which attribute minicircular mt genomes in lice to the adoption of blood-feeding in the Anoplura are not supported by this expanded data set as minicircles are found in multiple non-blood feeding louse groups but are not found in the blood-feeding genus Heterodoxus. In contrast, a mechanist explanation based on the loss of mtSSB suggests that minicircles may be selectively favoured due to the incapacity of the mt replisome to synthesize long replicative products without mtSSB and thus the loss of this gene lead to the formation of minicircles in lice.

'Royal' pediculosis in Renaissance Italy: lice in the mummy of the King of Naples Ferdinand II of Aragon (1467-1496).

PubMed

Fornaciari, Gino; Giuffra, Valentina; Marinozzi, Silvia; Picchi, Malayka Samantha; Masetti, Massimo

2009-07-01

Pediculosis seems to have afflicted humans since the most ancient times and lice have been found in several ancient human remains. Examination of the head hair and pubic hair of the artificial mummy of Ferdinand II of Aragon (1467-1496), King of Naples, revealed a double infestation with two different species of lice, Pediculus capitis, the head louse, and Pthirus pubis, the pubic louse. The hair samples were also positive for the presence of mercury, probably applied as an anti-pediculosis therapy. This is the first time that these parasites have been found in the hair of a king, demonstrating that even members of the wealthy classes in the Renaissance were subject to louse infestation.

Flight tests show potential benefits of data link as primary communication medium

NASA Technical Reports Server (NTRS)

Scanlon, Charles H.; Knox, Charles E.

1991-01-01

Message exchange for air traffic control (ATC) purposes via data link offers the potential benefits of increasing the airspace system safety and efficiency. This is accomplished by reducing communication errors and relieving the overloaded ATC radio frequencies, which hamper efficient message exchanges during peak traffic periods in many busy terminal areas. However, the many uses and advantages of data link create additional questions concerning the interface among the human-users and the cockpit and ground systems. A flight test was conducted in the NASA Langley B-737 airplane to contrast flight operations using current voice communications with the use of data link for transmitting both strategic and tactical ATC clearances during a typical commercial airline flight from takeoff to landing. Commercial airplane pilots were used as test subjects.

Traditional Chinese medicine for treatment of alcoholism: from ancient to modern.

PubMed

Liu, Qing; Lawrence, Andrew J; Liang, Jian-Hui

2011-01-01

Alcohol has long been used as a daily beverage in China and around the world. It is a medicinal substance with various biological activities. In fact, alcohol has played an important role in the development of traditional Chinese medicine (TCM), within which it is considered as the earliest exhilarant and anaesthetic. Yet, as a substance with great potency of misuse and addiction, the consumption of alcohol can lead to serious damage to individual health and the society. Over the past 20 years, alcohol abuse or alcoholism has become an increasing social problem in China along with the rapid economic development. China, the country of origin for TCM, has accumulated abundant clinical experience in the treatment of alcoholism with its ancient medicine. In the present research, we have summarized clinical and primary studies concerning various remedies of TCM for alcohol abuse, including herbal components (such as Kudzu/Pueraria Lobata, Pediculus melo, Hypericumpperforatum L.), decoctions and acupuncture.

A New Clade of African Body and Head Lice Infected by Bartonella quintana and Yersinia pestis-Democratic Republic of the Congo.

PubMed

Drali, Rezak; Shako, Jean-Christophe; Davoust, Bernard; Diatta, Georges; Raoult, Didier

2015-11-01

The human body louse is known as a vector for the transmission of three serious diseases-specifically, epidemic typhus, trench fever, and relapsing fever caused by Rickettsia prowazekii, Bartonella quintana, and Borrelia recurrentis, respectively-that have killed millions of people. It is also suspected in the transmission of a fourth pathogen, Yersinia pestis, which is the etiologic agent of plague. To date, human lice belonging to the genus Pediculus have been classified into three mitochondrial clades: A, B, and C. Here, we describe a fourth mitochondrial clade, Clade D, comprising head and body lice. Clade D may be a vector of B. quintana and Y. pestis, which is prevalent in a highly plague-endemic area near the Rethy Health District, Orientale Province, Democratic Republic of the Congo. © The American Society of Tropical Medicine and Hygiene.

Public access management as an adaptive wildlife management tool

USGS Publications Warehouse

Ouren, Douglas S.; Watts, Raymond D.

2005-01-01

One key issue in the Black Mesa – Black Canyon area is the interaction between motorized vehicles and. The working hypothesis for this study is that early season elk movement onto private lands and the National Park is precipitated by increased use of Off Highway Vehicles (OHV’s). Data on intensity of motorized use is extremely limited. In this study, we monitor intensity of motorized vehicle and trail use on elk movements and habitat usage and analyze interactions. If management agencies decide to alter accessibility, we will monitor wildlife responses to changes in the human-use regime. This provides a unique opportunity for adaptive management experimentation based on coordinated research and monitoring. The products from this project will provide natural resource managers across the nation with tools and information to better meet these resource challenges.

Subjective stress factors in centrifuge training for military aircrews.

PubMed

Lin, Pei-Chun; Wang, Jenhung; Li, Shih-Chin

2012-07-01

This study investigates stress-influence factors perceived by military aircrews undergoing centrifuge training, which lowers the incidence of G-induced loss of consciousness (G-LOC) for the crews of high-performance combat aircrafts. We used questionnaires to assess the subjective stress-influence factors of crews undergoing centrifuge training. Professionals in aviation physiology identified attributes measuring the perceived stress induced by centrifuge training, which were segmented into three constructs by factor analysis, theory lecture, centrifuge equipment, and physical fitness. Considerable interpenetration was discernible between these factors and military rank, age, length of service, flight hours accrued, and type of aircraft piloted. Identifying and quantifying the perceived stressors experienced in human-use centrifuge training enables aviators, astronauts, and air forces of the world to determine which constructs perceptibly increase or alleviate the perceived stress undergone by trainees when partaking in centrifuge training. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Heart rate and pulmonary function while wearing the launch-entry crew escape suit (LES) during + Gx acceleration and simulated Shuttle launch

NASA Technical Reports Server (NTRS)

Krutz, Robert W., Jr.; Bagian, James P.; Burton, Russell R.; Meeker, Larry J.

1990-01-01

Space shuttle crewmembers have been equipped with a launch-entry crew escape system (LES) since the Challenger accident in 1986. Some crewmembers, wearing the new pressure suit, have reported breathing difficulties and increased effort to achieve the desired range of motion. This study was conducted to quantify the reported increased physical workloads and breathing difficulty associated with wearing the LES. Both veteran astronauts and centrifuge panel members were exposed to various + Gx profiles (including simulated shuttle launch) + Gx on the USAF School of Aerospace Medicine (USAFSAM) human-use centrifuge. Maximum heart rate data showed no increased workload associated with arm and head movement in the LES when compared to the flight suit/helmet ensemble (LEH). However, the LES did impose a significant increase in breathing difficulty beginning at +2.5 Gx which was demonstrated by a decrease in forced vital capacity and subjected questionnaries.

Lipid nanoparticle vectorization of indocyanine green improves fluorescence imaging for tumor diagnosis and lymph node resection.

PubMed

Navarro, Fabrice P; Berger, Michel; Guillermet, Stéphanie; Josserand, Véronique; Guyon, Laurent; Neumann, Emmanuelle; Vinet, Françoise; Texier, Isabelle

2012-10-01

Fluorescence imaging is opening a new era in image-guided surgery and other medical applications. The only FDA approved contrast agent in the near infrared is IndoCyanine Green (ICG), which despites its low toxicity, displays poor chemical and optical properties for long-term and sensitive imaging applications in human. Lipid nanoparticles are investigated for improving ICG optical properties and in vivo fluorescence imaging sensitivity. 30 nm diameter lipid nanoparticles (LNP) are loaded with ICG. Their characterization and use for tumor and lymph node imaging are described. Nano-formulation benefits dye optical properties (6 times improved brightness) and chemical stability (>6 months at 4 degrees C in aqueous buffer). More importantly, LNP vectorization allows never reported sensitive and prolonged (>1 day) labeling of tumors and lymph nodes. Composed of human-use approved ingredients, this novel ICG nanometric formulation is foreseen to expand rapidly the field of clinical fluorescence imaging applications.

The origin and distribution of human lice in the world.

PubMed

Boutellis, Amina; Abi-Rached, Laurent; Raoult, Didier

2014-04-01

Two genera of lice parasitize humans: Pthirus and Pediculus. The latter is of significant public health importance and comprises two ecotypes: the body louse and the head louse. These ecotypes are morphologically and genetically notably similar; the body louse is responsible for three infectious diseases: Louse-borne epidemic typhus, relapsing fever, and trench fever. Mitochondrial DNA studies have shown that there are three obviously divergent clades of head lice (A, B and C), and only one clade of body lice is shared with head lice (clade A). Each clade has a unique geographic distribution. Lice have been parasitizing humans for millions of years and likely dispersed throughout the World with the human migrations out of Africa, so they can be good markers for studying human evolution. Here, we present an overview of the origin of human lice and their role in vector pathogenic bacteria that caused epidemics, and we review the association between lice clades and human migrations. Copyright © 2014 Elsevier B.V. All rights reserved.

Isolated Ficus trees deliver dual conservation and development benefits in a rural landscape.

PubMed

Cottee-Jones, H Eden W; Bajpai, Omesh; Chaudhary, Lal B; Whittaker, Robert J

2015-11-01

Many of the world's rural populations are dependent on the local provision of economically and medicinally important plant resources. However, increasing land-use intensity is depleting these resources, reducing human welfare, and thereby constraining development. Here we investigate a low cost strategy to manage the availability of valuable plant resources, facilitated by the use of isolated Ficus trees as restoration nuclei. We surveyed the plants growing under 207 isolated trees in Assam, India, and categorized them according to their local human-uses. We found that Ficus trees were associated with double the density of important high-grade timber, firewood, human food, livestock fodder, and medicinal plants compared to non-Ficus trees. Management practices were also important in determining the density of valuable plants, with grazing pressure and land-use intensity significantly affecting densities in most categories. Community management practices that conserve isolated Ficus trees, and restrict livestock grazing and high-intensity land-use in their vicinity, can promote plant growth and the provision of important local resources.

Chemicals of emerging concern in water and bottom sediment in the Great Lakes Basin, 2012: collection methods, analytical methods, quality assurance, and study data

USGS Publications Warehouse

Lee, Kathy E.; Langer, Susan K.; Menheer, Michael A.; Hansen, Donald S.; Foreman, William T.; Furlong, Edward T.; Jorgenson, Zachary G.; Choy, Steven J.; Moore, Jeremy N.; Banda, JoAnn; Gefell, Daniel J.

2015-01-01

During this study, 53 environmental samples, 4 field duplicate samples, and 8 field spike samples of bottom sediment and laboratory matrix-spike samples were analyzed for a wide variety of CECs at the USGS National Water Quality Laboratory using laboratory schedule 5433 for wastewater indicators; research method 6434 for steroid hormones, sterols, and bisphenol A; and research method 9008 for human-use pharmaceuticals and antidepressants. Forty of the 57 chemicals analyzed using laboratory schedule 5433 had detectable concentrations ranging from 1 to 49,000 micrograms per kilogram. Fourteen of the 20 chemicals analyzed using research method 6434 had detectable concentrations ranging from 0.04 to 24,940 nanograms per gram. Ten of the 20 chemicals analyzed using research method 9008 had detectable concentrations ranging from 0.59 to 197.5 micrograms per kilogram. Five of the 11 chemicals analyzed using research method 9008 had detectable concentrations ranging from 1.16 to 25.0 micrograms per kilogram.

Effects of alewife predation on zooplankton populations in Lake Michigan

USGS Publications Warehouse

Wells, LaRue

1970-01-01

The zooplankton populations in southeastern Lake Michigan underwent striking, size-related changes between 1954 and 1966. Forms that decline sharply were the largest cladocerans (Leptodora kindtii, Daphnia galeata, and D. retrocurva), the largest calanoid copepods (Limnocalanus macrurus, Epischura lacustris, and Diaptomus sicilis), and the largest cyclopoid copepod (Mesocyclops edax). Two of these, D. galeata and M. edax (both abundant in 1954), became extremely rare. Certain medium-sized or small species increased in numbers: Daphnia longiremis, Holopedium gibberum, Polyphemus pediculus, Bosmina longirostris, Bosmina coregoni, Ceriodaphnia sp., Cyclops bicuspidatus, Cyclops vernalis, and Diaptomus ashlandi. Evidence is strong that the changes were due to selective predation by alewives. The alewife was uncommon in southeastern Lake Michigan in 1954 but had increased to enormous proportions by 1966; there was a massive dieoff in spring 1967, and abundance remained relatively low in 1968. The composition of zooplankton populations in 1968 generally had shifted back toward that of 1954, although D. galeata and M. edax remained rare. The average size, and size at onset of maturity, of D. retrocurva decreased noticeably between 1954 and 1966 but increased between 1966 and 1968.

In vitro efficacy of synthetic skin repellent IR3535 on head lice (Pediculus capitis).

PubMed

Rupes, Vaclav; Vlckova, Jana; Kollarova, Helena; Horakova, Dagmar; Mazanek, Libor; Kensa, Michal

2013-10-01

In in vitro tests, skin repellent IR3535, applied in the form of the Diffusil H Prevental product in an aerosol bomb (active compound 20%), killed 100% of head lice (females and males) and nymphs 2 and 3, when directly sprayed at a dose of 0.94 mg of the active compound per square centimeter. Crawling lice exposed for 1 min on the filter paper impregnated by the same concentration showed no effort to suck blood 30 min after exposition. Twenty hours later, their mortality rate was 11 %. After the lice had been exposed for approximately 1 min (until they actively left the area) on 5 cm round areas of skin of test persons treated with the repellent at a mean total dose of 23.3 mg of active compound, they showed no effort to suck blood on the clean skin of other test person either immediately after exposure or 30 min later. Their mortality after 20 h ranged from 59 to 16%, depending on the time elapsed from skin treatment (10 min to 27 h).

An Environmental Risk Assessment for Human-Use Trimethoprim in European Surface Waters

PubMed Central

Straub, Jürg Oliver

2013-01-01

An environmental risk assessment (ERA) for the aquatic compartment in Europe from human use was developed for the old antibiotic Trimethoprim (TMP), comparing exposure and effects. The exposure assessment is based on European risk assessment default values on one hand and is refined with documented human use figures in Western Europe from IMS Health and measured removal in wastewater treatment on the other. The resulting predicted environmental concentrations (PECs) are compared with measured environmental concentrations (MECs) from Europe, based on a large dataset incorporating more than 1800 single MECs. On the effects side, available chronic ecotoxicity data from the literature were complemented by additional, new chronic results for fish and other organisms. Based on these data, chronic-based deterministic predicted no effect concentrations (PNECs) were derived as well as two different probabilistic PNEC ranges. The ERA compares surface water PECs and MECs with aquatic PNECs for TMP. Based on all the risk characterization ratios (PEC÷PNEC as well as MEC÷PNEC) and risk graphs, there is no significant risk to surface waters. PMID:27029296

Water-quality data for the Russian River Basin, Mendocino and Sonoma Counties, California, 2005-2010

USGS Publications Warehouse

Anders, Robert; Davidek, Karl; Stoeckel, Donald M.

2011-01-01

Field measurements included discharge, barometric pressure, dissolved oxygen, pH, specific conductance, temperature, and turbidity. All samples were analyzed for nutrients, major ions, trace metals, total and dissolved organic carbon, organic wastewater compounds, standard bacterial indicators, and the stable isotopes of hydrogen and oxygen. Standard bacterial indicators included total coliform, Escherichia coli, enterococci, and Clostridium perfringens for the period 2005 through 2007, and total and fecal coliform, and enterococci for 2010. In addition, enrichment of enterococci was performed on all surface-water samples collected during summer 2006, for detection of the human-associated enterococcal surface protein in Enterococcus faecium to assess the presence of sewage effluent in the Russian River. Other analyses included organic wastewater compounds of bed sediment samples collected from four Russian River sites during 2005; carbon-13 isotopic values of the dissolved inorganic carbon for surface-water and groundwater samples collected during 2006; human-use pharmaceuticals on Russian River samples collected during 2007 and 2010; and the radiogenic isotopes tritium and carbon-14 for groundwater samples collected during 2008.

Determination of human-use pharmaceuticals in filtered water by direct aqueous injection: high-performance liquid chromatography/tandem mass spectrometry

USGS Publications Warehouse

Furlong, Edward T.; Noriega, Mary C.; Kanagy, Christopher J.; Kanagy, Leslie K.; Coffey, Laura J.; Burkhardt, Mark R.

2014-01-01

This report describes a method for the determination of 110 human-use pharmaceuticals using a 100-microliter aliquot of a filtered water sample directly injected into a high-performance liquid chromatograph coupled to a triple-quadrupole tandem mass spectrometer using an electrospray ionization source operated in the positive ion mode. The pharmaceuticals were separated by using a reversed-phase gradient of formic acid/ammonium formate-modified water and methanol. Multiple reaction monitoring of two fragmentations of the protonated molecular ion of each pharmaceutical to two unique product ions was used to identify each pharmaceutical qualitatively. The primary multiple reaction monitoring precursor-product ion transition was quantified for each pharmaceutical relative to the primary multiple reaction monitoring precursor-product transition of one of 19 isotope-dilution standard pharmaceuticals or the pesticide atrazine, using an exact stable isotope analogue where possible. Each isotope-dilution standard was selected, when possible, for its chemical similarity to the unlabeled pharmaceutical of interest, and added to the sample after filtration but prior to analysis. Method performance for each pharmaceutical was determined for reagent water, groundwater, treated drinking water, surface water, treated wastewater effluent, and wastewater influent sample matrixes that this method will likely be applied to. Each matrix was evaluated in order of increasing complexity to demonstrate (1) the sensitivity of the method in different water matrixes and (2) the effect of sample matrix, particularly matrix enhancement or suppression of the precursor ion signal, on the quantitative determination of pharmaceutical concentrations. Recovery of water samples spiked (fortified) with the suite of pharmaceuticals determined by this method typically was greater than 90 percent in reagent water, groundwater, drinking water, and surface water. Correction for ambient environmental concentrations of pharmaceuticals hampered the determination of absolute recoveries and method sensitivity of some compounds in some water types, particularly for wastewater effluent and influent samples. The method detection limit of each pharmaceutical was determined from analysis of pharmaceuticals fortified at multiple concentrations in reagent water. The calibration range for each compound typically spanned three orders of magnitude of concentration. Absolute sensitivity for some compounds, using isotope-dilution quantitation, ranged from 0.45 to 94.1 nanograms per liter, primarily as a result of the inherent ionization efficiency of each pharmaceutical in the electrospray ionization process. Holding-time studies indicate that acceptable recoveries of pharmaceuticals can be obtained from filtered water samples held at 4 °C for as long as 9 days after sample collection. Freezing samples to provide for storage for longer periods currently (2014) is under evaluation by the National Water Quality Laboratory.

Management and Treatment of Human Lice

PubMed Central

Sangaré, Abdoul Karim; Doumbo, Ogobara K.

2016-01-01

Of the three lice (head, body, and pubic louse) that infest humans, the body louse is the species involved in epidemics of louse-borne typhus, trench fever, and relapsing fever, but all the three cause pediculosis. Their infestations occur today in many countries despite great efforts to maintain high standards of public health. In this review, literature searches were performed through PubMed, Medline, Google Scholar, and EBSCOhost, with key search words of “Pediculus humanus”, “lice infestation”, “pediculosis”, and “treatment”; and controlled clinical trials were viewed with great interest. Removing lice by hand or with a lice comb, heating infested clothing, and shaving the scalp were some of the oldest methods of controlling human lice. Despite the introduction of other resources including cresol, naphthalene, sulfur, mercury, vinegar, petroleum, and insecticides, the numbers of lice infestation cases and resistance have increased. To date, viable alternative treatments to replace insecticides have been developed experimentally in vitro. Today, the development of new treatment strategies such as symbiotic treatment and synergistic treatment (antibiotics + ivermectin) in vitro has proved effective and is promising. Here, we present an overview on managing and treating human lice and highlight new strategies to more effectively fight pediculosis and prevent resistance. PMID:27529073

The effects of hydrological dynamics on benthic diatom community structure in a highly stratified estuary: The case of the Ebro Estuary (Catalonia, Spain)

NASA Astrophysics Data System (ADS)

Rovira, L.; Trobajo, R.; Leira, M.; Ibáñez, C.

2012-04-01

This study of the distribution of benthic diatom assemblages and their relationship with environmental factors in a highly stratified Mediterranean estuary, i.e. the Ebro Estuary, shows the importance of hydrological dynamics to explain the features of the diatom community in such an estuary, where river flow magnitude and fluctuations imply strong physicochemical variability especially in sites close to the sea. Eight sites along the estuary were sampled during 2007-2008 both at superficial and deep water layers, in order to gather both horizontal and vertical estuarine physicochemical and hydrological gradients. Canonical Variates Analysis and Hierarchical Cluster Analysis segregated diatom community in two assemblages depending on the dynamics of the salt-wedge. The diatom assemblages of riverine conditions (i.e. without salt-wedge influence) where characterised by high abundances of Cocconeis placentula var. euglypta and Amphora pediculus, meanwhile high abundances of Nizschia frustulum and Nitzschia inconspicua were characteristic of estuarine conditions (i.e. under salt-wedge influence). Redundancy Analysis showed that both diatom assemblages responded seasonally to Ebro River flows, especially in estuarine conditions, where fluctuating conditions affected diatom assemblages both at spatial and temporal scale.

[Petechial typhus. History of men, armies and pedicula].

PubMed

Sabbatani, Sergio

2006-09-01

Since the Classical age, humankind has had to cope with petechial typhus, especially during wars and famine. Epidemics chiefly occurred during sieges and followed the paths of armies, when infected soldiers transmitted the infection to populations with whom they came into contact. Winter exacerbated the disease due to the use of unhygienic woollen clothes that allowed the spread of pediculosis. It was only in the early 18th century that petechial typhus outbreaks diminished thanks to the use of Marseille soap and to the new custom of changing clothing at bedtime. In many military campaigns, deaths from typhus were higher than those due to war wounds: recent studies established that the French defeat during the Napoleonic Russian military campaign has to be attributed more to typhus than to the military superiority of the enemy. Indeed, the contagion is estimated to have affected 80% of the 600,000 troops involved. The role of Pediculus as a vehicle of infection established in 1909 by Charles Nicolle, microbiological isolation performed by Howard Ricketts and Stanislaus von Prowazck, and finally the advent of antibiotic therapy, all laid the basis for controlling the disease in the 20th century.

The empty OR-process analysis and a new concept for flexible and modular use in minimal invasive surgery.

PubMed

Eckmann, Christian; Olbrich, Guenter; Shekarriz, Hodjat; Bruch, Hans-Peter

2003-01-01

The reproducible advantages of minimal invasive surgery have led to a worldwide spread of these techniques. Nevertheless, the increasing use of technology causes problems in the operating room (OR). The workstation environment and workflow are handicapped by a great number of isolated solutions that demand a large amount of space. The Center of Excellence in Medical Technology (CEMET) was established in 2001 as an institution for a close cooperation between users, science, and manufacturers of medical devices in the State of Schleswig-Holstein, Germany. The future OR, as a major project, began with a detailed process analysis, which disclosed a large number of medical devices with different interfaces and poor standardisation as main problems. Smaller and more flexible devices are necessary, as well as functional modules located outside the OR. Only actuators should be positioned near the operation area. The future OR should include a flexible-room concept and less equipment than is in use currently. A uniform human-user interface is needed to control the OR environment. This article addresses the need for a clear workspace environment, intelligent-user interfaces, and flexible-room concept to improve the potentials in use of minimal invasive surgery.

Identification of Porphyromonas gingivalis proteins secreted by the Por secretion system.

PubMed

Sato, Keiko; Yukitake, Hideharu; Narita, Yuka; Shoji, Mikio; Naito, Mariko; Nakayama, Koji

2013-01-01

The Gram-negative bacterium Porphyromonas gingivalis possesses a number of potential virulence factors for periodontopathogenicity. In particular, cysteine proteinases named gingipains are of interest given their abilities to degrade host proteins and process other virulence factors such as fimbriae. Gingipains are translocated on the cell surface or into the extracellular milieu by the Por secretion system (PorSS), which consists of a number of membrane or periplasmic proteins including PorK, PorL, PorM, PorN, PorO, PorP, PorQ, PorT, PorU, PorV (PG27, LptO), PorW and Sov. To identify proteins other than gingipains secreted by the PorSS, we compared the proteomes of P. gingivalis strains kgp rgpA rgpB (PorSS-proficient strain) and kgp rgpA rgpB porK (PorSS-deficient strain) using two-dimensional gel electrophoresis and peptide-mass fingerprinting. Sixteen spots representing 10 different proteins were present in the particle-free culture supernatant of the PorSS-proficient strain but were absent or faint in that of the PorSS-deficient strain. These identified proteins possessed the C-terminal domains (CTDs), which had been suggested to form the CTD protein family. These results indicate that the PorSS is used for secretion of a number of proteins other than gingipains and that the CTDs of the proteins are associated with the PorSS-dependent secretion. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Structural Insights into the PorK and PorN Components of the Porphyromonas gingivalis Type IX Secretion System.

PubMed

Gorasia, Dhana G; Veith, Paul D; Hanssen, Eric G; Glew, Michelle D; Sato, Keiko; Yukitake, Hideharu; Nakayama, Koji; Reynolds, Eric C

2016-08-01

The type IX secretion system (T9SS) has been recently discovered and is specific to Bacteroidetes species. Porphyromonas gingivalis, a keystone pathogen for periodontitis, utilizes the T9SS to transport many proteins including the gingipain virulence factors across the outer membrane and attach them to the cell surface via a sortase-like mechanism. At least 11 proteins have been identified as components of the T9SS including PorK, PorL, PorM, PorN and PorP, however the precise roles of most of these proteins have not been elucidated and the structural organization of these components is unknown. In this study, we purified PorK and PorN complexes from P. gingivalis and using electron microscopy we have shown that PorN and the PorK lipoprotein interact to form a 50 nm diameter ring-shaped structure containing approximately 32-36 subunits of each protein. The formation of these rings was dependent on both PorK and PorN, but was independent of PorL, PorM and PorP. PorL and PorM were found to form a separate stable complex. PorK and PorN were protected from proteinase K cleavage when present in undisrupted cells, but were rapidly degraded when the cells were lysed, which together with bioinformatic analyses suggests that these proteins are exposed in the periplasm and anchored to the outer membrane via the PorK lipid. Chemical cross-linking and mass spectrometry analyses confirmed the interaction between PorK and PorN and further revealed that they interact with the PG0189 outer membrane protein. Furthermore, we established that PorN was required for the stable expression of PorK, PorL and PorM. Collectively, these results suggest that the ring-shaped PorK/N complex may form part of the secretion channel of the T9SS. This is the first report showing the structural organization of any T9SS component.

Structural Insights into the PorK and PorN Components of the Porphyromonas gingivalis Type IX Secretion System

PubMed Central

Gorasia, Dhana G.; Veith, Paul D.; Hanssen, Eric G.; Glew, Michelle D.; Sato, Keiko; Yukitake, Hideharu; Nakayama, Koji; Reynolds, Eric C.

2016-01-01

The type IX secretion system (T9SS) has been recently discovered and is specific to Bacteroidetes species. Porphyromonas gingivalis, a keystone pathogen for periodontitis, utilizes the T9SS to transport many proteins including the gingipain virulence factors across the outer membrane and attach them to the cell surface via a sortase-like mechanism. At least 11 proteins have been identified as components of the T9SS including PorK, PorL, PorM, PorN and PorP, however the precise roles of most of these proteins have not been elucidated and the structural organization of these components is unknown. In this study, we purified PorK and PorN complexes from P. gingivalis and using electron microscopy we have shown that PorN and the PorK lipoprotein interact to form a 50 nm diameter ring-shaped structure containing approximately 32–36 subunits of each protein. The formation of these rings was dependent on both PorK and PorN, but was independent of PorL, PorM and PorP. PorL and PorM were found to form a separate stable complex. PorK and PorN were protected from proteinase K cleavage when present in undisrupted cells, but were rapidly degraded when the cells were lysed, which together with bioinformatic analyses suggests that these proteins are exposed in the periplasm and anchored to the outer membrane via the PorK lipid. Chemical cross-linking and mass spectrometry analyses confirmed the interaction between PorK and PorN and further revealed that they interact with the PG0189 outer membrane protein. Furthermore, we established that PorN was required for the stable expression of PorK, PorL and PorM. Collectively, these results suggest that the ring-shaped PorK/N complex may form part of the secretion channel of the T9SS. This is the first report showing the structural organization of any T9SS component. PMID:27509186

A protein secretion system linked to bacteroidete gliding motility and pathogenesis

PubMed Central

Sato, Keiko; Naito, Mariko; Yukitake, Hideharu; Hirakawa, Hideki; Shoji, Mikio; McBride, Mark J.; Rhodes, Ryan G.; Nakayama, Koji

2009-01-01

Porphyromonas gingivalis secretes strong proteases called gingipains that are implicated in periodontal pathogenesis. Protein secretion systems common to other Gram-negative bacteria are lacking in P. gingivalis, but several proteins, including PorT, have been linked to gingipain secretion. Comparative genome analysis and genetic experiments revealed 11 additional proteins involved in gingipain secretion. Six of these (PorK, PorL, PorM, PorN, PorW, and Sov) were similar in sequence to Flavobacterium johnsoniae gliding motility proteins, and two others (PorX and PorY) were putative two-component system regulatory proteins. Real-time RT-PCR analysis revealed that porK, porL, porM, porN, porP, porT, and sov were down-regulated in P. gingivalis porX and porY mutants. Disruption of the F. johnsoniae porT ortholog resulted in defects in motility, chitinase secretion, and translocation of a gliding motility protein, SprB adhesin, to the cell surface, providing a link between a unique protein translocation system and a motility apparatus in members of the Bacteroidetes phylum. PMID:19966289

Differential Regulation of Duplicate Light-Dependent Protochlorophyllide Oxidoreductases in the Diatom Phaeodactylum tricornutum

PubMed Central

Hunsperger, Heather M.; Cattolico, Rose Ann

2016-01-01

Background Diatoms (Bacilliariophyceae) encode two light-dependent protochlorophyllide oxidoreductases (POR1 and POR2) that catalyze the penultimate step of chlorophyll biosynthesis in the light. Algae live in dynamic environments whose changing light levels induce photoacclimative metabolic shifts, including altered cellular chlorophyll levels. We hypothesized that the two POR proteins may be differentially adaptive under varying light conditions. Using the diatom Phaeodactylum tricornutum as a test system, differences in POR protein abundance and por gene expression were examined when this organism was grown on an alternating light:dark cycles at different irradiances; exposed to continuous light; and challenged by a significant decrease in light availability. Results For cultures maintained on a 12h light: 12h dark photoperiod at 200μE m−2 s−1 (200L/D), both por genes were up-regulated during the light and down-regulated in the dark, though por1 transcript abundance rose and fell earlier than that of por2. Little concordance occurred between por1 mRNA and POR1 protein abundance. In contrast, por2 mRNA and POR2 protein abundances followed similar diurnal patterns. When 200L/D P. tricornutum cultures were transferred to continuous light (200L/L), the diurnal regulatory pattern of por1 mRNA abundance but not of por2 was disrupted, and POR1 but not POR2 protein abundance dropped steeply. Under 1200μE m−2 s−1 (1200L/D), both por1 mRNA and POR1 protein abundance displayed diurnal oscillations. A compromised diel por2 mRNA response under 1200L/D did not impact the oscillation in POR2 abundance. When cells grown at 1200L/D were then shifted to 50μE m−2 s−1 (50L/D), por1 and por2 mRNA levels decreased swiftly but briefly upon light reduction. Thereafter, POR1 but not POR2 protein levels rose significantly in response to this light stepdown. Conclusion Given the sensitivity of diatom por1/POR1 to real-time light cues and adherence of por2/POR2 regulation to the diurnal cycle, we suggest that POR1 supports photoacclimation, whereas POR2 is the workhorse for daily chlorophyll synthesis. PMID:27367227

The PorX Response Regulator of the Porphyromonas gingivalis PorXY Two-Component System Does Not Directly Regulate the Type IX Secretion Genes but Binds the PorL Subunit

PubMed Central

Vincent, Maxence S.; Durand, Eric; Cascales, Eric

2016-01-01

The Type IX secretion system (T9SS) is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion or cell surface exposition of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY, and PorX encode typical two-component system (TCS) sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN, and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we demonstrate that PorX does not bind T9SS gene promoters and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS. PMID:27630829

The clinical trials supporting benzyl alcohol lotion 5% (Ulesfia): a safe and effective topical treatment for head lice (pediculosis humanus capitis).

PubMed

Meinking, Terri L; Villar, Maria E; Vicaria, Maureen; Eyerdam, Debbie H; Paquet, Diane; Mertz-Rivera, Kamara; Rivera, Hector F; Hiriart, Javier; Reyna, Susan

2010-01-01

Benzyl alcohol lotion 5% (BAL 5%) is a non-neurotoxic topical head lice treatment that is safe and effective in children as young as 6 months of age. The safety and efficacy of this pediculicide has been studied in 695 (confirm number) subjects in all phases of clinical development. Scanning electron micrographs (SEM) demonstrated that the active agent appears to stun the breathing spiracles open, enabling the vehicle to penetrate the respiratory mechanism (spiracles), therefore asphyxiating the lice. Initial phase II trials compared this novel product to RID using identical volumes of treatment (4 oz/application) and yielding, almost, identical efficacy. This outcome pointed to the significant importance of completely saturating the hair with the product in order to achieve maximum treatment success. A second phase II trial, which allowed the use of sufficient product to saturate the hair, resulted in 100% efficacy after both 10 and 30 minute treatments. A third phase II trial verified an effective dose. Phase III trials compared BAL 5% to vehicle placebo for two 10-minute applications. It proved to be safe and effective (p < 0.001) for treatment of head lice and is the first FDA-approved non-neurotoxic lice treatment, now available in the United States as Ulesfia lotion.

Euthanasia, assisted suicide, and the philosophical anthropology of Karol Wojtyla.

PubMed

Fernandes, Ashley K

2001-12-01

The lack of consensus in American society regarding the permissibility of assisted suicide and euthanasia is due in large part to a failure to address the nature of the human person involved in the ethical act itself. For Karol Wojtyla, philosopher and Pope, ethical action finds meaning only in an authentic understanding of the person; but it is through acting (actus humanus) alone that the human person reveals himself. Knowing what the person ought to be cannot be divorced from what he ought to do; for Wojtyla, the structure of the ethical "do"--the act itself--comes first. The current paper will focus on four arguments used to justify assisted suicide and euthanasia: (1) the argument from autonomy, (2) the argument from compassion, (3) the argument from the evil of suffering, and (4) the argument from the loss of dignity. It will seek to answer each claim from the perspective of Karol Wojtyla's philosophical anthropology. Much of this will come from his defining work in pure philosophy, The Acting Person (1969). The final part of the paper will suggest some positive solutions to the stalemate over the euthanasia debate, again drawn from Wojtyla's idea of human fufillment through participation with the other, and with the community itself.

Annotation of the Asian Citrus Psyllid Genome Reveals a Reduced Innate Immune System

PubMed Central

Arp, Alex P.; Hunter, Wayne B.; Pelz-Stelinski, Kirsten S.

2016-01-01

Citrus production worldwide is currently facing significant losses due to citrus greening disease, also known as Huanglongbing. The citrus greening bacteria, Candidatus Liberibacter asiaticus (CLas), is a persistent propagative pathogen transmitted by the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae). Hemipterans characterized to date lack a number of insect immune genes, including those associated with the Imd pathway targeting Gram-negative bacteria. The D. citri draft genome was used to characterize the immune defense genes present in D. citri. Predicted mRNAs identified by screening the published D. citri annotated draft genome were manually searched using a custom database of immune genes from previously annotated insect genomes. Toll and JAK/STAT pathways, general defense genes Dual oxidase, Nitric oxide synthase, prophenoloxidase, and cellular immune defense genes were present in D. citri. In contrast, D. citri lacked genes for the Imd pathway, most antimicrobial peptides, 1,3-β-glucan recognition proteins (GNBPs), and complete peptidoglycan recognition proteins. These data suggest that D. citri has a reduced immune capability similar to that observed in A. pisum, P. humanus, and R. prolixus. The absence of immune system genes from the D. citri genome may facilitate CLas infections, and is possibly compensated for by their relationship with their microbial endosymbionts. PMID:27965582

Neurotechnology for monitoring and restoring sensory, motor, and autonomic functions

NASA Astrophysics Data System (ADS)

Wu, Pae C.; Knaack, Gretchen; Weber, Douglas J.

2016-05-01

The rapid and exponential advances in micro- and nanotechnologies over the last decade have enabled devices that communicate directly with the nervous system to measure and influence neural activity. Many of the earliest implementations focused on restoration of sensory and motor function, but as knowledge of physiology advances and technology continues to improve in accuracy, precision, and safety, new modes of engaging with the autonomic system herald an era of health restoration that may augment or replace many conventional pharmacotherapies. DARPA's Biological Technologies Office is continuing to advance neurotechnology by investing in neural interface technologies that are effective, reliable, and safe for long-term use in humans. DARPA's Hand Proprioception and Touch Interfaces (HAPTIX) program is creating a fully implantable system that interfaces with peripheral nerves in amputees to enable natural control and sensation for prosthetic limbs. Beyond standard electrode implementations, the Electrical Prescriptions (ElectRx) program is investing in innovative approaches to minimally or non-invasively interface with the peripheral nervous system using novel magnetic, optogenetic, and ultrasound-based technologies. These new mechanisms of interrogating and stimulating the peripheral nervous system are driving towards unparalleled spatiotemporal resolution, specificity and targeting, and noninvasiveness to enable chronic, human-use applications in closed-loop neuromodulation for the treatment of disease.

Escherichia coli and enterococci at beaches in the Grand Traverse Bay, Lake Michigan: Sources, characteristics, and environmental pathways

USGS Publications Warehouse

Haack, S.K.; Fogarty, L.R.; Wright, C.

2003-01-01

This study quantified Escherichia coli(EC) and enterococci (ENT) in beach waters and dominant source materials, correlated these with ambient conditions, and determined selected EC genotypes and ENT phenotypes. Bathing-water ENT criteria were exceeded more frequently than EC criteria, providing conflicting interpretations of water quality. Dominant sources of EC and ENT were bird feces (108/d/bird), storm drains (107/d), and river water (1011/d); beach sands, shallow groundwater and detritus were additional sources. Beach-water EC genotypes and ENT phenotypes formed clusters with those from all source types, reflecting diffuse inputs. Some ENT isolates had phenotypes similar to those of human pathogens and/or exhibited high-level resistance to human-use antibiotics. EC and ENT concentrations were influenced by collection time and wind direction. There was a 48-72-h lag between rainfall and elevated EC concentrations at three southern shoreline beaches, but no such lag at western and eastern shoreline beaches, reflecting the influence of beach orientation with respect to cyclic (3-5 d) summer weather patterns. In addition to local contamination sources and processes, conceptual or predictive models of Great Lakes beach water quality should consider regional weather patterns, lake hydrodynamics, and the influence of monitoring method variables (time of day, frequency).

Differential regulation of duplicate light-dependent protochlorophyllide oxidoreductases in the diatom Phaeodactylum tricornutum

DOE PAGES

Hunsperger, Heather M.; Ford, Christopher J.; Miller, James S.; ...

2016-07-01

Diatoms (Bacilliariophyceae) encode two light-dependent protochlorophyllide oxidoreductases (POR1 and POR2) that catalyze the penultimate step of chlorophyll biosynthesis in the light. Algae live in dynamic environments whose changing light levels induce photoacclimative metabolic shifts, including altered cellular chlorophyll levels. We hypothesized that the two POR proteins may be differentially adaptive under varying light conditions. Using the diatom Phaeodactylum tricornutum as a test system, differences in POR protein abundance and por gene expression were examined when this organism was grown on an alternating light:dark cycles at different irradiances; exposed to continuous light; and challenged by a significant decrease in light availability.more » As a result, for cultures maintained on a 12h light: 12h dark photoperiod at 200μEm –2 s –1 ( 200L/D), both por genes were up-regulated during the light and down-regulated in the dark, though por1 transcript abundance rose and fell earlier than that of por2. Little concordance occurred between por1 mRNA and POR1 protein abundance. In contrast, por2 mRNA and POR2 protein abundances followed similar diurnal patterns. When 200L/D P. tricornutum cultures were transferred to continuous light ( 200L/L), the diurnal regulatory pattern of por1 mRNA abundance but not of por2 was disrupted, and POR1 but not POR2 protein abundance dropped steeply. Under 1200μEm –2 s –1 ( 1200L/D), both por1 mRNA and POR1 protein abundance displayed diurnal oscillations. A compromised diel por2 mRNA response under 1200L/D did not impact the oscillation in POR2 abundance. When cells grown at 1200L/D were then shifted to 50μEm –2 s –1 (50L/D), por1 and por2 mRNA levels decreased swiftly but briefly upon light reduction. Thereafter, POR1 but not POR2 protein levels rose significantly in response to this light stepdown.« less

A study on the stability of O{sub 2} on oxometalloporphyrins by the first principles calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kubota, Yoshiyuki; Escano, Mary Clare Sison; Dy, Eben Sy

2007-05-21

The authors investigated the interaction of oxometalloporphyrins (MO(por))--specifically, MoO(por), WO(por), TiO(por), VO(por), and CrO(por)--with O{sub 2} by using first principles calculations. MoO(por) and WO(por) undergo reactions with O{sub 2}; on the other hand, TiO(por), VO(por), and CrO(por) do not. Next, they compared the interaction of MoO(por) and WO(por) with O{sub 2}. Activation barriers for the reactions of MoO(por) and WO(por) with a side-on O{sub 2} are small. For MoO(por)(O{sub 2}), the activation barrier for the reverse reaction that liberates O{sub 2} is also small; however, that for WO(por)(O{sub 2}) is large. The experimental results that photoirradiation with visible light ormore » heating of Mo {sup VI}O(tmp)(O{sub 2}) regenerates Mo {sup VI}O(tmp) by liberating O{sub 2} while W {sup VI}O(tmp)(O{sub 2}) does not [J. Tachibana, T. Imamura, and Y. Sasaki, Bull. Chem. Soc. Jpn. 71, 363 (1998)] are explained by the difference in activation barriers of the reverse reactions. This means that bonds formed between the W atom and O{sub 2} are stronger than those between the Mo atom and O{sub 2}. The bond strengths can be explained by differences in the energy levels between the highest occupied molecular orbital of MoO(por) and WO(por), which are mainly formed from the a orbitals of the central metal atom and {pi}{sup *} orbitals of O{sub 2}.« less

Examining the prevalence rate of Pediculus capitis infestation according to sex and social factors in primary school children

PubMed Central

Doroodgar, Abbas; Sadr, Fakhraddin; Doroodgar, Masoud; Doroodgar, Moein; Sayyah, Mansour

2014-01-01

Objective To determine the prevalence rate of head louse infestation among elementary students, and examine the associated factors with infection in the city of Aran and Bidgol. Methods A total of 19 boys' and girls' primary schools were selected by multistage, systematic random sampling. Overall, 3 590 students were examined for head lice infestation in urban areas of Aran and Bidgol during 2008. The diagnosis was based on live louse or nit on the scalp of students. The students were screened by standard questionnaire and demographic data in addition to related information were obtained by interview and observation. The data were analyzed by SPSS software using chi-square and Fisher's exact tests. Results The mean age of students was (8.68±1.58) years ranging between 6-12 years. The total prevalence of head louse infestation was 0.47%. This rate was 0.42% and 0.05% in female and male, respectively. There was a significant association between pediculosis and sex, father's job, mother's education, access to bathroom in home, prior infection, drug use and nationality, respectively (P<0.05). Conclusions The results showed that pediculosis was not a major health priority among primary school in city of Aran and Bidgol. However, enhancing the knowledge of students about head lice infestation and the existence of health teachers in schools can play a significant role in disease control.

The mode of action of dimeticone 4% lotion against head lice, Pediculus capitis

PubMed Central

Burgess, Ian F

2009-01-01

Background Treatment of head lice using physically acting preparations based on silicones is currently replacing insecticide use due to widespread resistance to neurotoxic agents. It has been postulated that some products act by asphyxiation, although the limited experimental evidence and the anatomy of the louse respiratory system suggest this is unlikely. Results Observation over several hours of lice treated using 4% high molecular weight dimeticone in a volatile silicone base showed that, although rapidly immobilised initially, the insects still exhibited small movements of extremities and death was delayed. One common effect of treatment is inhibition of the louse's ability to excrete water by transpiration through the spiracles. Inability to excrete water that is ingested as part of the louse blood meal appears to subject the louse gut to osmotic stress resulting in rupture. Scanning electron microscopy coupled with X-ray microanalysis to detect silicon showed dimeticone lotion is deposited in the spiracles and distal region of the tracheae of lice and in some cases blocks the lumen or opening entirely. Conclusion This work raises doubts that lice treated using dimeticone preparations die from anoxia despite blockage of the outer respiratory tract because movements can be observed for hours after exposure. However, the blockage inhibits water excretion, which causes physiological stress that leads to death either through prolonged immobilisation or, in some cases, disruption of internal organs such as the gut. PMID:19232080

The effect of β-saturated pyrrolic rings on the electronic structures and aromaticity of magnesium porphyrin derivatives: a density functional study.

PubMed

Wan, Liang; Qi, Dongdong; Zhang, Yuexing

2011-09-01

Density functional theory (DFT) calculation on the molecular structures, molecular orbitals, electronic absorption spectra, and magnetic properties of magnesium porphyrin (MgPor) and a series of five hydrogenated magnesium porphyrin complexes with different number of β-saturated pyrrolic rings, namely MgPor-β-1Hy, MgPor-β-opp-2Hy, MgPor-β-adj-2Hy, MgPor-β-3Hy, and MgPor-β-4Hy, clarifies the red-shift of the lowest energy absorption band from chlorophyll a to bacteriochlorophyll and reveals the strong chemical stability for both of them. The energy levels of highest occupied molecular orbitals (HOMO) and HOMO-1 for MgPor are reversed upon hydrogenation at β-positions (2 and 3, 7 and 8, 12 and 13, and 17 and 18) of porphyrin ring. Along with the increase of β-saturated pyrrolic rings from 1, 2, 3, to 4, the HOMO energy increases from -4.78 eV to -3.10 eV in a regular manner. In contrast, the lowest unoccupied molecular orbitals (LUMO) energy levels of MgPor, MgPor-β-1Hy, and MgPor-β-opp-2Hy are very similar with each other. As a result, the lowest energy absorption band involving main transition from HOMO to LUMO is red-shifted from MgPor-β-1Hy to MgPor-β-opp-2Hy which is representative of chlorophyll a and bacteriochlorophyll, respectively. Natural hydroporphyrins represented by MgPor, MgPor-β-1Hy, and MgPor-β-opp-2Hy have turned out to be aromatic and stable enough, in good accordance with the ubiquity of their derivatives in the nature. In contrast, MgPor-β-adj-2Hy, MgPor-β-3Hy, and MgPor-β-4Hy with relatively weak aromaticity seem to be unstable and therefore were not found in nature. Copyright © 2011 Elsevier Inc. All rights reserved.

Type IX secretion: the generation of bacterial cell surface coatings involved in virulence, gliding motility and the degradation of complex biopolymers.

PubMed

Veith, Paul D; Glew, Michelle D; Gorasia, Dhana G; Reynolds, Eric C

2017-10-01

The Type IX secretion system (T9SS) is present in over 1000 sequenced species/strains of the Fibrobacteres-Chlorobi-Bacteroidetes superphylum. Proteins secreted by the T9SS have an N-terminal signal peptide for translocation across the inner membrane via the SEC translocon and a C-terminal signal for secretion across the outer membrane via the T9SS. Nineteen protein components of the T9SS have been identified including three, SigP, PorX and PorY that are involved in regulation. The inner membrane proteins PorL and PorM and the outer membrane proteins PorK and PorN interact and a complex comprising PorK and PorN forms a large ring structure of 50 nm in diameter. PorU, PorV, PorQ and PorZ form an attachment complex on the cell surface of the oral pathogen, Porphyromonas gingivalis. P. gingivalis T9SS substrates bind to PorV suggesting that after translocation PorV functions as a shuttle protein to deliver T9SS substrates to the attachment complex. The PorU component of the attachment complex is a novel Gram negative sortase which catalyses the cleavage of the C-terminal signal and conjugation of the protein substrates to lipopolysaccharide, anchoring them to the cell surface. This review presents an overview of the T9SS focusing on the function of T9SS substrates and machinery components. © 2017 John Wiley & Sons Ltd.

Portable exhausters POR-004 SKID B, POR-005 SKID C, POR-006 SKID D storage plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, O.D.

1997-09-04

This document provides a storage plan for portable exhausters POR-004 SKID B, POR-005 SKID C, AND POR-006 SKID D. The exhausters will be stored until they are needed by the TWRS (Tank Waste Remediation Systems) Saltwell Pumping Program. The storage plan provides criteria for portable exhauster storage, periodic inspections during storage, and retrieval from storage.

Effect of P450 Oxidoreductase Polymorphisms on the Metabolic Activities of Ten Cytochrome P450s Varied by Polymorphic CYP Genotypes in Human Liver Microsomes.

PubMed

Fang, Yan; Gao, Na; Tian, Xin; Zhou, Jun; Zhang, Hai-Feng; Gao, Jie; He, Xiao-Pei; Wen, Qiang; Jia, Lin-Jing; Jin, Han; Qiao, Hai-Ling

2018-06-27

Background/ Aims: Little is known about the effect of P450 oxidoreductase (POR) gene polymorphisms on the activities of CYPs with multiple genotypes. We genotyped 102 human livers for 18 known POR single nucleotide polymorphisms (SNPs) with allelic frequencies greater than 1% as well as for 27 known SNPs in 10 CYPs. CYP enzyme activities in microsomes prepared from these livers were determined by measuring probe substrate metabolism by high performance liquid chromatograph. We found that the effects of the 18 POR SNPs on 10 CYP activities were CYP genotype-dependent. The POR mutations were significantly associated with decreased overall Km for CYP2B6 and 2E1, and specific genotypes within CYP1A2, 2A6, 2B6, 2C8, 2D6 and 2E1 were identified as being affected by these POR SNPs. Notably, the effect of a specific POR mutation on the activity of a CYP genotype could not be predicted from other CYP genotypes of even the same CYP. When combining one POR SNP with other POR SNPs, a hitherto unrecognized effect of multiple-site POR gene polymorphisms (MSGP) on CYP activity was uncovered, which was not necessarily consistent with the effect of either single POR SNP. The effects of POR SNPs on CYP activities were not only CYP-dependent, but more importantly, CYP genotype-dependent. Moreover, the effect of a POR SNP alone and in combination with other POR SNPs (MSGP) was not always consistent, nor predictable. Understanding the impact of POR gene polymorphisms on drug metabolism necessitates knowing the complete SNP complement of POR and the genotype of the relevant CYPs. © 2018 The Author(s). Published by S. Karger AG, Basel.

Portable exhauster POR-007/Skid E and POR-008/Skid F storage plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, O.D.

1998-07-25

This document provides storage requirements for 1,000 CFM portable exhausters POR-O07/Skid E and POR-008/Skid F. These requirements are presented in three parts: preparation for storage, storage maintenance and testing, and retrieval from storage. The exhauster component identification numbers listed in this document contain the prefix POR-007 or POR-008 depending on which exhauster is being used.

Assessment of Household Disposal of Pharmaceuticals in Lebanon: Management Options to Protect Water Quality and Public Health

NASA Astrophysics Data System (ADS)

Massoud, May A.; Chami, Ghida; Al-Hindi, Mahmoud; Alameddine, Ibrahim

2016-05-01

Pharmaceuticals comprise an extensive group of compounds whose release into the environment has potential adverse impacts on human health and aquatic ecosystems. In many developing countries the extent of the problem and the occurrence of pharmaceuticals in water bodies are generally unknown. While thousands of tons of pharmaceutical substances are used annually, little information is known about their final fate after their intended use. This paper focuses on better understanding the management of human-use pharmaceutical wastes generated at the residential level within the Administrative Beirut Area. A survey encompassing 300 households was conducted. Results revealed that the majority of respondents were found to dispose of their unwanted medications, mainly through the domestic solid waste stream. Willingness to participate in a future collection program was found to be a function of age, medical expenditure, and the respondents' views towards awareness and the importance of establishing a collection system for pharmaceutical wastes. Respondents who stated a willingness to participate in a collection program and/or those who believed in the need for awareness programs on the dangers of improper medical waste disposal tended to favor more collection programs managed by the government as compared to a program run by pharmacies or to the act of re-gifting medication to people in need. Ultimately, collaboration and coordination between concerned stakeholders are essential for developing a successful national collection plan.

CHEMICAL MARKERS OF HUMAN WASTE ...

EPA Pesticide Factsheets

Giving public water authorities a tool to monitor and measure levels of human waste contamination of waters simply and rapidly would enhance public protection. This methodology, using both urobilin and azithromycin (or any other human-use pharmaceutical) could be used to give public water authorities a rapid (24- hrs) and definitive method for measuring human waste contamination The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-soluble pharmaceuticals in source waters at levels that could be environmentally significant (at concentrations less than parts per billion, ppb). IAG with USGS ends in FY05. APM 20 due in FY05.Subtask 2: Coordination of interagency research and public outreach activities for PPCPs. Participate on NSTC Health and Environment subco

CHEMICAL MARKERS OF HUMAN WASTE ...

EPA Pesticide Factsheets

Giving public water authorities a tool to monitor and measure levels of human waste contamination of waters simply and rapidly would enhance public protection. This methodology, using both urobilin and azithromycin (or any other human-use pharmaceutical) could be used to give public water authorities a rapid (24- hrs) and definitive method for measuring human waste contamination. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-soluble pharmaceuticals in source waters at levels that could be environmentally significant (at concentrations less than parts per billion, ppb). IAG with USGS ends in FY05. APM 20 due in FY05.Subtask 2: Coordination of interagency research and public outreach activities for PPCPs. Participate on NSTC Health and Environment subc

Primary language and cultural background as factors in resident burnout in medical specialties: a study in a bilingual US city.

PubMed

Afzal, Khalid I; Khan, Farhan M; Mulla, Zuber; Akins, Ralista; Ledger, Elizabeth; Giordano, Frank L

2010-07-01

The aim of this study was to identify the degree of burnout among resident physicians enrolled in seven postgraduate training programs at Texas Tech University Health Sciences Center (TTUHSC), Paul L. Foster School of Medicine, El Paso, Texas, as it related to residents' age, gender, marital status, number of hours worked per week, primary language, race/ethnicity, and cultural background. : The Maslach Burnout Inventory Human Service Survey (MBI) was administered to measure the level of burnout according to the prevalence of emotional exhaustion (EE), depersonalization (DP), and reduced personal accomplishment (PA). : Eighty-one percent of the residents at TTUHSC participated in the study. Residents raised in the United States or Canada comprised 28% and 35% of the study, and all reported English as their primary language. The EE scale was significant for obstetrics/gynecology (OB/GYN) residents (prevalence odds ratio [POR] = 13.55, P = 0.02) and psychiatry (PSY) residents (POR = 6.50, P = 0.03). Emergency medicine (EM) residents (POR = 23.35, P = 0.002), OB/GYN (POR = 10.89, P = 0.02), and general surgery (GS) (POR = 6.24, P = 0.03) residents had high DP. Internal medicine (IM) residents (primarily Spanish-speaking) reported significantly low EE (POR = 0.22, P = 0.03) and PA (POR = 0.09, P = 0.001) scores. Residents from the United States or Canada who reported English as their primary language and noted their race as white, had high EE (POR = 3.06, P = 0.03; POR = 5.61, P = 0.0001; POR = 2.91, P = 0.004), DP (POR = 3.19, P = 0.02; POR = 8.34, P < or = 0.0001; POR = 4.70, P < or = 0.0001) and PA (POR = 2.61, P = 0.02; POR = 2.35, P = 0.05, POR 0.29, P = 0.3) scores. Using valid measures, this pilot study identified a statistically significant relationship between burnout and residents' race/ethnicity, primary language, and cultural background. Larger studies with similar focus would be necessary to generalize these findings. At-risk residents in bilingual locations should be provided with cultural awareness workshops, language assistance programs, as well as senior resident and faculty mentors.

Altered heme catabolism by heme oxygenase-1 caused by mutations in human NADPH cytochrome P450 reductase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pandey, Amit V., E-mail: amit@pandeylab.org; Flueck, Christa E.; Mullis, Primus E.

2010-09-24

Research highlights: {yields} Mutations in POR identified from patients lead to reduced HO-1 activities. {yields} POR mutation Y181D affecting FMN binding results in total loss of HO-1 activity. {yields} POR mutations A287P, C569Y and V608F, lost 50-70% activity. {yields} Mutations in FAD binding domain, R457H, Y459H and V492E lost all HO-1 activity. {yields} POR polymorphisms P228L, R316W, G413S, A503V and G504R have normal activity. -- Abstract: Human heme oxygenase-1 (HO-1) carries out heme catabolism supported by electrons supplied from the NADPH through NADPH P450 reductase (POR, CPR). Previously we have shown that mutations in human POR cause a rare formmore » of congenital adrenal hyperplasia. In this study, we have evaluated the effects of mutations in POR on HO-1 activity. We used purified preparations of wild type and mutant human POR and in vitro reconstitution with purified HO-1 to measure heme degradation in a coupled assay using biliverdin reductase. Here we show that mutations in POR found in patients may reduce HO-1 activity, potentially influencing heme catabolism in individuals carrying mutant POR alleles. POR mutants Y181D, A457H, Y459H, V492E and R616X had total loss of HO-1 activity, while POR mutations A287P, C569Y and V608F lost 50-70% activity. The POR variants P228L, R316W and G413S, A503V and G504R identified as polymorphs had close to WT activity. Loss of HO-1 activity may result in increased oxidative neurotoxicity, anemia, growth retardation and iron deposition. Further examination of patients affected with POR deficiency will be required to assess the metabolic effects of reduced HO-1 activity in affected individuals.« less

Heterologous expression of equine CYP3A94 and investigation of a tunable system to regulate co-expressed NADPH P450 oxidoreductase levels.

PubMed

Dettwiler, Ramona; Schmitz, Andrea L; Plattet, Philippe; Zielinski, Jana; Mevissen, Meike

2014-01-01

The activity of cytochrome P450 enzymes depends on the enzyme NADPH P450 oxidoreductase (POR). The aim of this study was to investigate the activity of the equine CYP3A94 using a system that allows to regulate the POR protein levels in mammalian cells. CYP3A94 and the equine POR were heterologously expressed in V79 cells. In the system used, the POR protein regulation is based on a destabilizing domain (DD) that transfers its instability to a fused protein. The resulting fusion protein is therefore degraded by the ubiquitin-proteasome system (UPS). Addition of "Shield-1" prevents the DD fusion protein from degradation. The change of POR levels at different Shield-1 concentrations was demonstrated by cytochrome c reduction, Western immunoblot analysis, and immunocytochemistry. The alteration of CYP3A94 activity was investigated using a substrate (BFC) known to detect CYP3A4 activity. Equine CYP3A94 was demonstrated to be metabolically active and its activity could be significantly elevated by co-expression of POR. Cytochrome c reduction was significantly increased in V79-CYP3A94/DD-POR cells compared to V79-CYP3A94 cells. Surprisingly, incubation with different Shield-1 concentrations resulted in a decrease in POR protein shown by Western immunoblot analysis. Cytochrome c reduction did not change significantly, but the CYP3A94 activity decreased more than 4-fold after incubation with 500 nM and 1 µM Shield-1 for 24 hours. No differences were obtained when V79-CYP3A94 POR cells with and without Shield-1 were compared. The basal activity levels of V79-CYP3A94/DD-POR cells were unexpectedly high, indicating that DD/POR is not degraded without Shield-1. Shield-1 decreased POR protein levels and CYP3A94 activity suggesting that Shield-1 might impair POR activity by an unknown mechanism. Although regulation of POR with the pPTuner system could not be obtained, the cell line V79-CYP3A94/DD-POR system can be used for further experiments to characterize the equine CYP3A94 since the CYP activity was significantly enhanced with co-expressed POR.

Heterologous Expression of Equine CYP3A94 and Investigation of a Tunable System to Regulate Co-Expressed NADPH P450 Oxidoreductase Levels

PubMed Central

Dettwiler, Ramona; Schmitz, Andrea L.; Plattet, Philippe; Zielinski, Jana; Mevissen, Meike

2014-01-01

The activity of cytochrome P450 enzymes depends on the enzyme NADPH P450 oxidoreductase (POR). The aim of this study was to investigate the activity of the equine CYP3A94 using a system that allows to regulate the POR protein levels in mammalian cells. CYP3A94 and the equine POR were heterologously expressed in V79 cells. In the system used, the POR protein regulation is based on a destabilizing domain (DD) that transfers its instability to a fused protein. The resulting fusion protein is therefore degraded by the ubiquitin-proteasome system (UPS). Addition of “Shield-1” prevents the DD fusion protein from degradation. The change of POR levels at different Shield-1 concentrations was demonstrated by cytochrome c reduction, Western immunoblot analysis, and immunocytochemistry. The alteration of CYP3A94 activity was investigated using a substrate (BFC) known to detect CYP3A4 activity. Equine CYP3A94 was demonstrated to be metabolically active and its activity could be significantly elevated by co-expression of POR. Cytochrome c reduction was significantly increased in V79-CYP3A94/DD-POR cells compared to V79-CYP3A94 cells. Surprisingly, incubation with different Shield-1 concentrations resulted in a decrease in POR protein shown by Western immunoblot analysis. Cytochrome c reduction did not change significantly, but the CYP3A94 activity decreased more than 4-fold after incubation with 500 nM and 1 µM Shield-1 for 24 hours. No differences were obtained when V79-CYP3A94 POR cells with and without Shield-1 were compared. The basal activity levels of V79-CYP3A94/DD-POR cells were unexpectedly high, indicating that DD/POR is not degraded without Shield-1. Shield-1 decreased POR protein levels and CYP3A94 activity suggesting that Shield-1 might impair POR activity by an unknown mechanism. Although regulation of POR with the pPTuner system could not be obtained, the cell line V79-CYP3A94/DD-POR system can be used for further experiments to characterize the equine CYP3A94 since the CYP activity was significantly enhanced with co-expressed POR. PMID:25415624

P450 oxidoreductase deficiency: a disorder of steroidogenesis with multiple clinical manifestations.

PubMed

Miller, Walter L

2012-10-23

Cytochrome P450 enzymes catalyze the biosynthesis of steroid hormones and metabolize drugs. There are seven human type I P450 enzymes in mitochondria and 50 type II enzymes in endoplasmic reticulum. Type II enzymes, including both drug-metabolizing and some steroidogenic enzymes, require electron donation from a two-flavin protein, P450 oxidoreductase (POR). Although knockout of the POR gene causes embryonic lethality in mice, we discovered human POR deficiency as a disorder of steroidogenesis associated with the Antley-Bixler skeletal malformation syndrome and found mild POR mutations in phenotypically normal adults with infertility. Assay results of mutant forms of POR using the traditional but nonphysiologic assay (reduction of cytochrome c) did not correlate with patient phenotypes; assays based on the 17,20 lyase activity of P450c17 (CYP17) correlated with clinical phenotypes. The POR sequence in 842 normal individuals revealed many polymorphisms; amino acid sequence variant A503V is encoded by ~28% of human alleles. POR A503V has about 60% of wild-type activity in assays with CYP17, CYP2D6, and CYP3A4, but nearly wild-type activity with P450c21, CYP1A2, and CYP2C19. Activity of a particular POR variant with one P450 enzyme will not predict its activity with another P450 enzyme: Each POR-P450 combination must be studied individually. Human POR transcription, initiated from an untranslated exon, is regulated by Smad3/4, thyroid receptors, and the transcription factor AP-2. A promoter polymorphism reduces transcription to 60% in liver cells and to 35% in adrenal cells. POR deficiency is a newly described disorder of steroidogenesis, and POR variants may account for some genetic variation in drug metabolism.

Patterns of coral disease across the Hawaiian Archipelago: Relating disease to environment

USGS Publications Warehouse

Aeby, G.S.; Williams, G.J.; Franklin, E.C.; Kenyon, J.; Cox, E.F.; Coles, S.; Work, Thierry M.

2011-01-01

In Hawaii, coral reefs occur across a gradient of biological (host abundance), climatic (sea surface temperature anomalies) and anthropogenic conditions from the human-impacted reefs of the main Hawaiian Islands (MHI) to the pristine reefs of the northwestern Hawaiian Islands (NWHI). Coral disease surveys were conducted at 142 sites from across the Archipelago and disease patterns examined. Twelve diseases were recorded from three coral genera (Porites, Montipora, Acropora) with Porites having the highest prevalence. Porites growth anomalies (PorGAs) were significantly more prevalent within and indicative of reefs in the MHI and Porites trematodiasis (PorTrm) was significantly more prevalent within and indicative of reefs in the NWHI. Porites tissue loss syndrome (PorTLS) was also important in driving regional differences but that relationship was less clear. These results highlight the importance of understanding disease ecology when interpreting patterns of disease occurrence. PorTrm is caused by a parasitic flatworm that utilizes multiple hosts during its life cycle (fish, mollusk and coral). All three hosts must be present for the disease to occur and higher host abundance leads to higher disease prevalence. Thus, a high prevalence of PorTrm on Hawaiian reefs would be an indicator of a healthy coral reef ecosystem. In contrast, the high occurrence of PorGAs within the MHI suggests that PorGAs are related, directly or indirectly, to some environmental co-factor associated with increased human population sizes. Focusing on the three indicator diseases (PorGAs, PorTrm, PorTLS) we used statistical modeling to examine the underlying associations between disease prevalence and 14 different predictor variables (biotic and abiotic). All three diseases showed positive associations with host abundance and negative associations with thermal stress. The association with human population density differed among disease states with PorGAs showing a positive and PorTrm showing a negative association, but no significant explanatory power was offered for PorTLS.

Patterns of Coral Disease across the Hawaiian Archipelago: Relating Disease to Environment

PubMed Central

Aeby, Greta S.; Williams, Gareth J.; Franklin, Erik C.; Kenyon, Jean; Cox, Evelyn F.; Coles, Steve; Work, Thierry M.

2011-01-01

In Hawaii, coral reefs occur across a gradient of biological (host abundance), climatic (sea surface temperature anomalies) and anthropogenic conditions from the human-impacted reefs of the main Hawaiian Islands (MHI) to the pristine reefs of the northwestern Hawaiian Islands (NWHI). Coral disease surveys were conducted at 142 sites from across the Archipelago and disease patterns examined. Twelve diseases were recorded from three coral genera (Porites, Montipora, Acropora) with Porites having the highest prevalence. Porites growth anomalies (PorGAs) were significantly more prevalent within and indicative of reefs in the MHI and Porites trematodiasis (PorTrm) was significantly more prevalent within and indicative of reefs in the NWHI. Porites tissue loss syndrome (PorTLS) was also important in driving regional differences but that relationship was less clear. These results highlight the importance of understanding disease ecology when interpreting patterns of disease occurrence. PorTrm is caused by a parasitic flatworm that utilizes multiple hosts during its life cycle (fish, mollusk and coral). All three hosts must be present for the disease to occur and higher host abundance leads to higher disease prevalence. Thus, a high prevalence of PorTrm on Hawaiian reefs would be an indicator of a healthy coral reef ecosystem. In contrast, the high occurrence of PorGAs within the MHI suggests that PorGAs are related, directly or indirectly, to some environmental co-factor associated with increased human population sizes. Focusing on the three indicator diseases (PorGAs, PorTrm, PorTLS) we used statistical modeling to examine the underlying associations between disease prevalence and 14 different predictor variables (biotic and abiotic). All three diseases showed positive associations with host abundance and negative associations with thermal stress. The association with human population density differed among disease states with PorGAs showing a positive and PorTrm showing a negative association, but no significant explanatory power was offered for PorTLS. PMID:21655248

Reduction in hepatic drug metabolizing CYP3A4 activities caused by P450 oxidoreductase mutations identified in patients with disordered steroid metabolism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flueck, Christa E.; Mullis, Primus E.; Pandey, Amit V., E-mail: amit@pandeylab.org

2010-10-08

Research highlights: {yields} Cytochrome P450 3A4 (CYP3A4), metabolizes 50% of drugs in clinical use and requires NADPH-P450 reductase (POR). {yields} Mutations in human POR cause congenital adrenal hyperplasia from diminished activities of steroid metabolizing P450s. {yields} We are reporting that mutations in POR may reduce CYP3A4 activity. {yields} POR mutants Y181D, A457H, Y459H, V492E and R616X lost 99%, while A287P, C569Y and V608F lost 60-85% CYP3A4 activity. {yields} Reduction of CYP3A4 activity may cause increased risk of drug toxicities/adverse drug reactions in patients with POR mutations. -- Abstract: Cytochrome P450 3A4 (CYP3A4), the major P450 present in human liver metabolizesmore » approximately half the drugs in clinical use and requires electrons supplied from NADPH through NADPH-P450 reductase (POR, CPR). Mutations in human POR cause a rare form of congenital adrenal hyperplasia from diminished activities of steroid metabolizing P450s. In this study we examined the effect of mutations in POR on CYP3A4 activity. We used purified preparations of wild type and mutant human POR and in vitro reconstitution with purified CYP3A4 to perform kinetic studies. We are reporting that mutations in POR identified in patients with disordered steroidogenesis/Antley-Bixler syndrome (ABS) may reduce CYP3A4 activity, potentially affecting drug metabolism in individuals carrying mutant POR alleles. POR mutants Y181D, A457H, Y459H, V492E and R616X had more than 99% loss of CYP3A4 activity, while POR mutations A287P, C569Y and V608F lost 60-85% activity. Loss of CYP3A4 activity may result in increased risk of drug toxicities and adverse drug reactions in patients with POR mutations.« less

Suppression of Cytochrome P450 Reductase (POR) Expression in Hepatoma Cells Replicates the Hepatic Lipidosis Observed in Hepatic POR-Null Mice

PubMed Central

Banerjee, Subhashis; Stolarczyk, Elzbieta I.; Zou, Ling

2011-01-01

Cytochrome P450 reductase (POR) is a microsomal electron transport protein essential to cytochrome P450-mediated drug metabolism and sterol and bile acid synthesis. The conditional deletion of hepatic POR gene expression in mice results in a marked decrease in plasma cholesterol levels counterbalanced by the accumulation of triglycerides in lipid droplets in hepatocytes. To evaluate the role of cholesterol and bile acid synthesis in this hepatic lipidosis, as well as the possible role of lipid transport from peripheral tissues, we developed a stable, small interfering RNA (siRNA)-mediated cell culture model for the suppression of POR. POR mRNA and protein expression were decreased by greater than 50% in McArdle-RH7777 rat hepatoma cells 10 days after transfection with a POR-siRNA expression plasmid, and POR expression was nearly completely extinguished by day 20. Immunofluorescent analysis revealed a marked accumulation of lipid droplets in cells by day 15, accompanied by a nearly 2-fold increase in cellular triglyceride content, replicating the lipidosis seen in hepatic POR-null mouse liver. In contrast, suppression of CYP51A1 (lanosterol demethylase) did not result in lipid accumulation, indicating that loss of cholesterol synthesis is not the basis for this lipidosis. Indeed, addition of cholesterol to the medium appeared to augment the lipidosis in POR-suppressed cells, whereas removal of lipids from the medium reversed the lipidosis. Oxysterols did not accumulate in POR-suppressed cells, discounting a role for liver X receptor in stimulating triglyceride synthesis, but addition of chenodeoxycholate significantly repressed lipid accumulation, suggesting that the absence of bile acids and loss of farnesoid X receptor stimulation lead to excessive triglyceride synthesis. PMID:21368239

Suppression of cytochrome P450 reductase (POR) expression in hepatoma cells replicates the hepatic lipidosis observed in hepatic POR-null mice.

PubMed

Porter, Todd D; Banerjee, Subhashis; Stolarczyk, Elzbieta I; Zou, Ling

2011-06-01

Cytochrome P450 reductase (POR) is a microsomal electron transport protein essential to cytochrome P450-mediated drug metabolism and sterol and bile acid synthesis. The conditional deletion of hepatic POR gene expression in mice results in a marked decrease in plasma cholesterol levels counterbalanced by the accumulation of triglycerides in lipid droplets in hepatocytes. To evaluate the role of cholesterol and bile acid synthesis in this hepatic lipidosis, as well as the possible role of lipid transport from peripheral tissues, we developed a stable, small interfering RNA (siRNA)-mediated cell culture model for the suppression of POR. POR mRNA and protein expression were decreased by greater than 50% in McArdle-RH7777 rat hepatoma cells 10 days after transfection with a POR-siRNA expression plasmid, and POR expression was nearly completely extinguished by day 20. Immunofluorescent analysis revealed a marked accumulation of lipid droplets in cells by day 15, accompanied by a nearly 2-fold increase in cellular triglyceride content, replicating the lipidosis seen in hepatic POR-null mouse liver. In contrast, suppression of CYP51A1 (lanosterol demethylase) did not result in lipid accumulation, indicating that loss of cholesterol synthesis is not the basis for this lipidosis. Indeed, addition of cholesterol to the medium appeared to augment the lipidosis in POR-suppressed cells, whereas removal of lipids from the medium reversed the lipidosis. Oxysterols did not accumulate in POR-suppressed cells, discounting a role for liver X receptor in stimulating triglyceride synthesis, but addition of chenodeoxycholate significantly repressed lipid accumulation, suggesting that the absence of bile acids and loss of farnesoid X receptor stimulation lead to excessive triglyceride synthesis.

Geographical variation of overweight, obesity and related risk factors: Findings from the European Health Examination Survey in Luxembourg, 2013-2015.

PubMed

Samouda, Hanen; Ruiz-Castell, Maria; Bocquet, Valery; Kuemmerle, Andrea; Chioti, Anna; Dadoun, Frédéric; Kandala, Ngianga-Bakwin; Stranges, Saverio

2018-01-01

The analyses of geographic variations in the prevalence of major chronic conditions, such as overweight and obesity, are an important public health tool to identify "hot spots" and inform allocation of funding for policy and health promotion campaigns, yet rarely performed. Here we aimed at exploring, for the first time in Luxembourg, potential geographic patterns in overweight/obesity prevalence in the country, adjusted for several demographic, socioeconomic, behavioural and health status characteristics. Data came from 720 men and 764 women, 25-64 years old, who participated in the European Health Examination Survey in Luxembourg (2013-2015). To investigate the geographical variation, geo-additive semi-parametric mixed model and Bayesian modelisations based on Markov Chain Monte Carlo techniques for inference were performed. Large disparities in the prevalence of overweight and obesity were found between municipalities, with the highest rates of obesity found in 3 municipalities located in the South-West of the country. Bayesian approach also underlined a nonlinear effect of age on overweight and obesity in both genders (significant in men) and highlighted the following risk factors: 1. country of birth for overweight in men born in a non-European country (Posterior Odds Ratio (POR): 3.24 [1.61-8.69]) and women born in Portugal (POR: 2.44 [1.25-4.43]), 2. low educational level (secondary or below) for overweight (POR: 1.66 (1.06-2.72)] and obesity (POR:2.09 [1.05-3.65]) in men, 3. single marital status for obesity in women (POR: 2.20 [1.24-3.91]), 4.fair (men: POR: 3.19 [1.58-6.79], women: POR: 2.24 [1.33-3.73]) to very bad health perception (men: POR: 15.01 [2.16-98.09]) for obesity, 5. sleeping more than 6 hours for obesity in unemployed men (POR: 3.66 [2.02-8.03]). Protective factors highlighted were: 1. single marital status against overweight (POR: [0.60 (0.38-0.96)]) and obesity (POR: 0.39 [0.16-0.84]) in men, 2. the fact to be widowed against overweight in women (POR: [0.30 (0.07-0.86)], as well as a non European country of birth (POR: 0.49 [0.19-0.98]), tertiary level of education (POR: 0.34 [0.18-0.64]), moderate alcohol consumption (POR: 0.54 [0.36-0.90]) and aerobic physical activity practice (POR: 0.44 [0.27-0.77]) against obesity in women. A double burden of environmental exposure due to historic mining and industrial activities and past economic vulnaribility in the South-West of the country may have participated to the higher prevalence of obesity found in this region. Other demographic, socioeconomic, behavioural and health status covariates could have been involved as well.

Alerta De Insecto-Escarabajo asiatico de antenoas largas

Treesearch

Marco A. Fonseca; Ronald F. Billings

Hay probablemente una sola generacion de ALB por a'o. Los escarabajos adultos por lo general estan presentes de mayo a octubre, pero se pueden encontrar mas temprano en la primavera o mas tarde en el oto?o si las temperaturas son calidas. Los adultos por lo general permanecen en el arbol del que emergieron o se pueden desplazar por distancias cortas hacia un...

Comparing the Efficacy of Commercially Available Insecticide and Dimeticone based Solutions on Head Lice, Pediculus capitis: in vitro Trials.

PubMed

Balcıoğlu, I Cüneyt; Karakuş, Mehmet; Arserim, Suha K; Limoncu, M Emin; Töz, Seray; Baştemur, Serkan; Öncel, Koray; Özbel, Yusuf

2015-12-01

Head lice infestation is a public health and social problem for almost all countries worldwide. For its treatment, insecticide and dimeticone-based solutions are currently available in the markets in many countries. We aimed to compare the efficacy of commercially available anti-head lice shampoos containing insecticide and physically effective products with different percentages of dimeticone using an in vitro technique. Head lice specimens were collected from primary school children using special plastic and metal combs. Anti-head lice products were commercially purchased and used directly. The specimens were placed one by one in 5-cm Petri dishes containing a slightly wet filter paper and were kept in a plastic cage at 28±2°C and 50%±20% relative humidity. A standardized protocol was used for testing all the products, and mortality data were obtained after 24 h. Two control tests were performed with each batch of trials. For each product and control, 10-20 head lice specimens were used, and the results were statistically analyzed. Our study demonstrated that among all the tested products, two products containing mineral oils [5.5% dimeticone & silicone (patented product) and dimeticone (no percentage mentioned in the prospectus) & cyclopentasiloxane] were found to be more effective for killing head lice in vitro. Physically effective products can be repetitively used because they are non-toxic and resistance to them is not expected. To control the infestation at a public level, the use of these products needs to be encouraged with respect to their cost price.

Making the invisible visible: improved electrospray ion formation of metalloporphyrins/-phthalocyanines by attachment of the formate anion (HCOO(-)).

PubMed

Hitzenberger, Jakob Felix; Dammann, Claudia; Lang, Nina; Lungerich, Dominik; García-Iglesias, Miguel; Bottari, Giovanni; Torres, Tomás; Jux, Norbert; Drewello, Thomas

2016-02-21

A protocol is developed for the coordination of the formate anion (HCOO(-)) to neutral metalloporphyrins (Pors) and -phthalocyanines (Pcs) containing divalent metals as a means to improve their ion formation in electrospray ionization (ESI). This method is particularly useful when the oxidation of the neutral metallomacrocycle fails. While focusing on Zn(II)Pors and Zn(II)Pcs, we show that formate is also readily attached to Mn(II), Mg(II) and Co(II)Pcs. However, for the Co(II)Pc secondary reactions can be observed. Upon collision-induced dissociation (CID), Zn(II)Por/Pc·formate supramolecular complexes can undergo the loss of CO2 in combination with transfer of a hydride anion (H(-)) to the zinc metal center. Further dissociation leads to electron transfer and hydrogen atom loss, generating a route to the radical anion of the Zn(II)Por/Pc without the need for electrochemical reduction, although the Zn(II)Por/Pc may have a too low electron affinity to allow electron transfer directly from the formate anion. In addition to single Por molecules, multi Por arrays were successfully analyzed by this method. In this case, multiple addition of formate occurs, giving rise to multiply charged species. In these multi Por arrays, complexation of the formate anion occurs by two surrounding Por units (sandwich). Therefore, the maximum attainment of formate anions in these arrays corresponds to the number of such sandwich complexes rather than the number of porphyrin moieties. The same bonding motif leads to dimers of the composition [(Zn(II)Por/Pc)2·HCOO](-). In these, the formate anion can act as a structural probe, allowing the distinction of isomeric ions with the formate bridging two macrocycles or being attached to a dimer of directly connected macrocycles.

Antigenic topology of chlamydial PorB protein and identification of targets for immune neutralization of infectivity.

PubMed

Kawa, Diane E; Stephens, Richard S

2002-05-15

The outer membrane protein PorB is a conserved chlamydial protein that functions as a porin and is capable of eliciting neutralizing Abs. A topological antigenic map was developed using overlapping synthetic peptides representing the Chlamydia trachomatis PorB sequence and polyclonal immune sera. To identify which antigenic determinants were surface accessible, monospecific antisera were raised to the PorB peptides and were used in dot-blot and ELISA-based absorption studies with viable chlamydial elementary bodies (EBs). The ability of the surface-accessible antigenic determinants to direct neutralizing Ab responses was investigated using standardized in vitro neutralization assays. Four major antigenic clusters corresponding to Phe(34)-Leu(59) (B1-2 and B1-3), Asp(112) -Glu(145) (B2-3 and B2-4), Gly(179)-Ala(225) (B3-2 to B3-4), and Val(261)-Asn(305) (B4-4 to B5-2) were identified. Collectively, the EB absorption and dot-blot assays established that the immunoreactive PorB Ags were exposed on the surface of chlamydial EBs. Peptide-specific antisera raised to the surface-accessible Ags neutralized chlamydial infectivity and demonstrated cross-reactivity to synthetic peptides representing analogous C. pneumoniae PorB sequences. Furthermore, neutralization of chlamydial infectivity by C. trachomatis PorB antisera was inhibited by synthetic peptides representing the surface-exposed PorB antigenic determinants. These findings demonstrate that PorB Ags may be useful for development of chlamydial vaccines.

Risk factors associated with human Rift Valley fever infection: systematic review and meta-analysis.

PubMed

Nicholas, Dennis E; Jacobsen, Kathryn H; Waters, Nigel M

2014-12-01

To identify risk factors for human Rift Valley fever virus (RVFV) infection. A systematic review identified 17 articles reporting on 16 studies examining risk factors for RVFV. Pooled odds ratios (pOR) were calculated for exposures examined in four or more studies. Being male [pOR = 1.4 (1.0, 1.8)], contact with aborted animal tissue [pOR = 3.4 (1.6, 7.3)], birthing an animal [pOR = 3.2 (2.4, 4.2)], skinning an animal [pOR = 2.5 (1.9, 3.2)], slaughtering an animal [pOR = 2.4 (1.4, 4.1)] and drinking raw milk [pOR = 1.8 (1.2, 2.6)] were significantly associated with RVF infection after meta-analysis. Other potential risk factors include sheltering animals in the home and milking an animal, which may both involve contact with animal body fluids. Based on the identified risk factors, use of personal protective equipment and disinfectants by animal handlers may help reduce RVFV transmission during outbreaks. Milk pasteurisation and other possible preventive methods require further investigation. © 2014 John Wiley & Sons Ltd.

Fecal Calprotectin Levels Are Closely Correlated with the Absence of Relevant Mucosal Lesions in Postoperative Crohn's Disease.

PubMed

Garcia-Planella, Esther; Mañosa, Míriam; Cabré, Eduard; Marín, Laura; Gordillo, Jordi; Zabana, Yamile; Boix, Jaume; Sáinz, Sergio; Domènech, Eugeni

2016-12-01

Fecal calprotectin (FC) is the best noninvasive biomarker of disease activity in inflammatory bowel disease. Its correlation with endoscopic mucosal lesions could save inconvenient, expensive, and repeated endoscopic examinations in particular clinical settings. To assess the correlation between FC and the existence and severity of endoscopic postoperative recurrence (POR), a group of clinically stable outpatients with Crohn's disease for whom an ileocolonoscopy was routinely planned to assess POR were invited to collect a stool sample before starting bowel cleansing to measure FC. POR was graded by means of Rutgeerts endoscopic score. One hundred nineteen ileocolonoscopies were included, 42% with endoscopic POR. FC was significantly lower in the absence of endoscopic POR and in the absence of any endoscopic lesion. The area under the receiver operating characteristic curve was 0.76 (95% confidence interval, 0.68-0.85) for the diagnosis of the absence of lesions and 0.75 (95% confidence interval, 0.66-0.84) for endoscopic POR. Better sensitivity and negative predictive value were observed when combining FC and serum C-reactive protein (CRP), leading to a sensitivity of 82%, a specificity of 53%, and negative and positive predictive values of 81% and 54%, respectively, for the prediction of endoscopic POR with a combination of FC 100 μg/g and CRP 5 mg/L cutoff values. FC correlates closely with endoscopic POR in clinically stable postoperative patients with Crohn's disease and, when used in combination with CRP, might save endoscopic examinations and allow for a high-grade suspicion of endoscopic POR in the long-term monitoring of these patients.

Outer membrane vesicles from Neisseria gonorrhoeae target PorB to mitochondria and induce apoptosis

PubMed Central

Elgass, Kirstin D.; Gabriel, Kipros; Dougan, Gordon; Lithgow, Trevor; Heinz, Eva

2018-01-01

Neisseria gonorrhoeae causes the sexually transmitted disease gonorrhoea by evading innate immunity. Colonizing the mucosa of the reproductive tract depends on the bacterial outer membrane porin, PorB, which is essential for ion and nutrient uptake. PorB is also targeted to host mitochondria and regulates apoptosis pathways to promote infections. How PorB traffics from the outer membrane of N. gonorrhoeae to mitochondria and whether it modulates innate immune cells, such as macrophages, remains unclear. Here, we show that N. gonorrhoeae secretes PorB via outer membrane vesicles (OMVs). Purified OMVs contained primarily outer membrane proteins including oligomeric PorB. The porin was targeted to mitochondria of macrophages after exposure to purified OMVs and wild type N. gonorrhoeae. This was associated with loss of mitochondrial membrane potential, release of cytochrome c, activation of apoptotic caspases and cell death in a time-dependent manner. Consistent with this, OMV-induced macrophage death was prevented with the pan-caspase inhibitor, Q-VD-PH. This shows that N. gonorrhoeae utilizes OMVs to target PorB to mitochondria and to induce apoptosis in macrophages, thus affecting innate immunity. PMID:29601598

Anti-inflammatory, Analgesic and Antiulcer properties of Porphyra vietnamensis.

PubMed

Bhatia, Saurabh; Sharma, Kiran; Sharma, Ajay; Nagpal, Kalpana; Bera, Tanmoy

2015-01-01

Aim of the present work was to investigate the anti-inflammatory, analgesic and antiulcer effects of red seaweed Porphyra vietnamensis (P. vietnamenis). Aqueous (POR) and alcoholic (PE) fractions were successfully isolated from P. vietnamenis. Further biological investigations were performed using a classic test of paw edema induced by carrageenan, writhing induced by acetic acid, hot plate method and naproxen induced gastro-duodenal ulcer. Among the fractions POR showed better activity. POR and PE significantly (p < 0.05) reduced carrageenan induced paw edema in a dose dependent manner. In the writhing test POR significantly (p < 0.05) reduced abdominal writhes than PE. In hot plate method POR showed better analgesic activity than PE. POR showed comparable ulcers reducing potential (p<0.01) to that of omeprazole, and has more ulcer reducing potential then PE. The results of this study demonstrated that P. vietnamenis aqueous fraction possesses biological activity that is close to the standards taken for the treatment of peripheral painful or/and inflammatory and ulcer conditions.

Disaster-related exposures and health effects among US Coast Guard responders to Hurricanes Katrina and Rita: a cross-sectional study.

PubMed

Rusiecki, Jennifer A; Thomas, Dana L; Chen, Ligong; Funk, Renée; McKibben, Jodi; Dayton, Melburn R

2014-08-01

Disaster responders work among poorly characterized physical and psychological hazards with little understood regarding health consequences of their work. A survey administered to 2834 US Coast Guard responders to Hurricanes Katrina and Rita provided data on exposures and health effects. Prevalence odds ratios (PORs) evaluated associations between baseline characteristics, missions, exposures, and health effects. Most frequent exposures were animal/insect vector (n = 1309; 46%) and floodwater (n = 817; 29%). Most frequent health effects were sunburn (n = 1119; 39%) and heat stress (n = 810; 30%). Significant positive associations were for mold exposure and sinus infection (POR = 10.39); carbon monoxide and confusion (POR = 6.27); lack of sleep and slips, trips, falls (POR = 3.34) and depression (POR = 3.01); being a Gulf-state responder and depression (POR = 3.22). Increasing protection for disaster responders requires provisions for adequate sleep, personal protective equipment, and access to medical and psychological support.

Anti-inflammatory, Analgesic and Antiulcer properties of Porphyra vietnamensis

PubMed Central

Bhatia, Saurabh; Sharma, Kiran; Sharma, Ajay; Nagpal, Kalpana; Bera, Tanmoy

2015-01-01

Objectives: Aim of the present work was to investigate the anti-inflammatory, analgesic and antiulcer effects of red seaweed Porphyra vietnamensis (P. vietnamenis). Materials and Methods: Aqueous (POR) and alcoholic (PE) fractions were successfully isolated from P. vietnamenis. Further biological investigations were performed using a classic test of paw edema induced by carrageenan, writhing induced by acetic acid, hot plate method and naproxen induced gastro-duodenal ulcer. Results: Among the fractions POR showed better activity. POR and PE significantly (p < 0.05) reduced carrageenan induced paw edema in a dose dependent manner. In the writhing test POR significantly (p < 0.05) reduced abdominal writhes than PE. In hot plate method POR showed better analgesic activity than PE. POR showed comparable ulcers reducing potential (p<0.01) to that of omeprazole, and has more ulcer reducing potential then PE. Conclusions: The results of this study demonstrated that P. vietnamenis aqueous fraction possesses biological activity that is close to the standards taken for the treatment of peripheral painful or/and inflammatory and ulcer conditions. PMID:25767759

La Resonancia J/$$\\psi$$ y Sus Implicaciones Para La Masa Del W (in Spanish)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanchez-Hernandez, Alberto

Es un placer agradecer a mi asesor el doctor Heriberto Castilla Valdez por brindarme sus conocimientos, experiencia y paciencia en el desarrollo de esta tesis; tambien quiero agradecer al profesor H.E. Fisk, por su apoyo econemico en mi estancia en Fermilab. De igual forma agradezco a los doctores Arturo Fernandez Telles, Miguel Angel Perez Angen y Rebeca Juarez Wisozka quienes me introdujeron al campo de la fisica experimental de altas energfas. Agradezco tambien a Maribel Rios Cruz, Ruben Flores Mendieta, Juan Morales Corona, Fabiola Vazquez Valencia, Salvador Carrillo Moreno y Cecilia Uribe Estrada por su amistad y compaiierismo durante elmore » desarrollo de mi maestria. Un especial agradecimiento a Ian Adam y Kina Denisenko por su valiosa ayuda, comentarios y discusiones durante mi estancia en Fermilab. Por ultimo quisiera agradecer a mis profesores, amigos y familiares quienes siempre me apoyaron y alentaron y al Consejo N acional de Ciencia y Tecnologfa asf como al Departamento de Fisica de Cinvestav por su apoyo econemlco.« less

Perception of Human-Derived Risk Influences Choice at Top of the Food Chain

PubMed Central

Cristescu, Bogdan; Stenhouse, Gordon B.; Boyce, Mark S.

2013-01-01

On human-used landscapes, animal behavior is a trade-off between maximizing fitness and minimizing human-derived risk. Understanding risk perception in wildlife can allow mitigation of anthropogenic risk, with benefits to long-term animal fitness. Areas where animals choose to rest should minimize risk from predators, which for large carnivores typically equate to humans. We hypothesize that high human activity leads to selection for habitat security, whereas low activity enables trading security for forage. We investigated selection of resting (bedding) sites by GPS radiocollared adult grizzly bears (n = 10) in a low density population on a multiple-use landscape in Canada. We compared security and foods at resting and random locations while accounting for land use, season, and time of day. On reclaimed mines with low human access, bears selected high horizontal cover far from trails, but did not avoid open (herbaceous) areas, resting primarily at night. In protected areas bears also bedded at night, in areas with berry shrubs and Hedysarum spp., with horizontal cover selected in the summer, during high human access. On public lands with substantial human recreation, bears bedded at day, selected resting sites with high horizontal cover in the summer and habitat edges, with bedding associated with herbaceous foods. These spatial and temporal patterns of selection suggest that bears perceive human-related risk differentially in relation to human activity level, season and time of day, and employ a security-food trade-off strategy. Although grizzly bears are presently not hunted in Alberta, their perceived risks associated with humans influence resting-site selection. PMID:24367549

Gliding Motility and Por Secretion System Genes Are Widespread among Members of the Phylum Bacteroidetes

PubMed Central

Zhu, Yongtao

2013-01-01

The phylum Bacteroidetes is large and diverse, with rapid gliding motility and the ability to digest macromolecules associated with many genera and species. Recently, a novel protein secretion system, the Por secretion system (PorSS), was identified in two members of the phylum, the gliding bacterium Flavobacterium johnsoniae and the nonmotile oral pathogen Porphyromonas gingivalis. The components of the PorSS are not similar in sequence to those of other well-studied bacterial secretion systems. The F. johnsoniae PorSS genes are a subset of the gliding motility genes, suggesting a role for the secretion system in motility. The F. johnsoniae PorSS is needed for assembly of the gliding motility apparatus and for secretion of a chitinase, and the P. gingivalis PorSS is involved in secretion of gingipain protease virulence factors. Comparative analysis of 37 genomes of members of the phylum Bacteroidetes revealed the widespread occurrence of gliding motility genes and PorSS genes. Genes associated with other bacterial protein secretion systems were less common. The results suggest that gliding motility is more common than previously reported. Microscopic observations confirmed that organisms previously described as nonmotile, including Croceibacter atlanticus, “Gramella forsetii,” Paludibacter propionicigenes, Riemerella anatipestifer, and Robiginitalea biformata, exhibit gliding motility. Three genes (gldA, gldF, and gldG) that encode an apparent ATP-binding cassette transporter required for F. johnsoniae gliding were absent from two related gliding bacteria, suggesting that the transporter may not be central to gliding motility. PMID:23123910

NADPH–Cytochrome P450 Oxidoreductase: Roles in Physiology, Pharmacology, and Toxicology

PubMed Central

Ding, Xinxin; Wolf, C. Roland; Porter, Todd D.; Pandey, Amit V.; Zhang, Qing-Yu; Gu, Jun; Finn, Robert D.; Ronseaux, Sebastien; McLaughlin, Lesley A.; Henderson, Colin J.; Zou, Ling; Flück, Christa E.

2013-01-01

This is a report on a symposium sponsored by the American Society for Pharmacology and Experimental Therapeutics and held at the Experimental Biology 2012 meeting in San Diego, California, on April 25, 2012. The symposium speakers summarized and critically evaluated our current understanding of the physiologic, pharmacological, and toxicological roles of NADPH–cytochrome P450 oxidoreductase (POR), a flavoprotein involved in electron transfer to microsomal cytochromes P450 (P450), cytochrome b5, squalene mono-oxygenase, and heme oxygenase. Considerable insight has been derived from the development and characterization of mouse models with conditional Por deletion in particular tissues or partial suppression of POR expression in all tissues. Additional mouse models with global or conditional hepatic deletion of cytochrome b5 are helping to clarify the P450 isoform- and substrate-specific influences of cytochrome b5 on P450 electron transfer and catalytic function. This symposium also considered studies using siRNA to suppress POR expression in a hepatoma cell–culture model to explore the basis of the hepatic lipidosis phenotype observed in mice with conditional deletion of Por in liver. The symposium concluded with a strong translational perspective, relating the basic science of human POR structure and function to the impacts of POR genetic variation on human drug and steroid metabolism. PMID:23086197

Influence of cytochrome P450 oxidoreductase genetic polymorphisms on CYP1A2 activity and inducibility by smoking.

PubMed

Dobrinas, Maria; Cornuz, Jacques; Pedrido, Leticia; Eap, Chin B

2012-02-01

Cytochrome P4501A2 (CYP1A2) presents a high interindividual variability in its activity and also in its inducibility by smoking. Cytochrome P450 oxidoreductase (POR) is an electron transfer protein that catalyzes the activity of several cytochromes P450. We aimed to study the influence of POR genetic polymorphisms on CYP1A2 activity while smoking and after smoking cessation, as well as on CYP1A2 inducibility. CYP1A2 activity was determined by the paraxanthine/caffeine ratio in 184 smokers and in 113 of these smokers who were abstinent during a 4-week period. Participants were genotyped for POR rs17148944G>A, rs10239977C>T, rs3815455C>T, rs2286823G>A, rs2302429G>A, and rs1057868C>T (POR*28) polymorphisms. While smoking, none of the tested POR polymorphisms showed a significant influence on CYP1A2 activity. After smoking cessation, significantly higher CYP1A2 activity was found in POR rs2302429A carriers (P=0.038) and in carriers of rs17148944G-rs10239977C-rs3815455T-rs2286823G-rs2302429A-rs1057868T haplotype (P=0.038), whereas carriers of POR rs2286823A (P=0.031) and of the rs17148944G-rs10239977C-rs3815455C-rs2286823A-rs2302429G-rs1057868C haplotype (P=0.031) had decreased CYP1A2 activity. In the complete regression model, only POR rs2302429G>A showed a significant effect (P=0.017). No influence of POR genotypes or haplotypes was observed on the inducibility of CYP1A2. POR genetic polymorphisms influence CYP1A2 basal but not induced activity and do not seem to influence CYP1A2 inducibility. Future work is warranted to identify other clinical and genetic factors that may explain the variability in CYP1A2 activity and inducibility by smoking.

Deletion of P399{sub E}401 in NADPH cytochrome P450 oxidoreductase results in partial mixed oxidase deficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flueck, Christa E., E-mail: christa.flueck@dkf.unibe.ch; Mallet, Delphine; Hofer, Gaby

2011-09-09

Highlights: {yields} Mutations in human POR cause congenital adrenal hyperplasia. {yields} We are reporting a novel 3 amino acid deletion mutation in POR P399{sub E}401del. {yields} POR mutation P399{sub E}401del decreased P450 activities by 60-85%. {yields} Impairment of steroid metabolism may be caused by multiple hits. {yields} Severity of aromatase inhibition is related to degree of in utero virilization. -- Abstract: P450 oxidoreductase (POR) is the electron donor for all microsomal P450s including steroidogenic enzymes CYP17A1, CYP19A1 and CYP21A2. We found a novel POR mutation P399{sub E}401del in two unrelated Turkish patients with 46,XX disorder of sexual development. Recombinant PORmore » proteins were produced in yeast and tested for their ability to support steroid metabolizing P450 activities. In comparison to wild-type POR, the P399{sub E}401del protein was found to decrease catalytic efficiency of 21-hydroxylation of progesterone by 68%, 17{alpha}-hydroxylation of progesterone by 76%, 17,20-lyase action on 17OH-pregnenolone by 69%, aromatization of androstenedione by 85% and cytochrome c reduction activity by 80%. Protein structure analysis of the three amino acid deletion P399{sub E}401 revealed reduced stability and flexibility of the mutant. In conclusion, P399{sub E}401del is a novel mutation in POR that provides valuable genotype-phenotype and structure-function correlation for mutations in a different region of POR compared to previous studies. Characterization of P399{sub E}401del provides further insight into specificity of different P450s for interaction with POR as well as nature of metabolic disruptions caused by more pronounced effect on specific P450s like CYP17A1 and aromatase.« less

Recombinant Salivary Proteins of Phlebotomus orientalis are Suitable Antigens to Measure Exposure of Domestic Animals to Sand Fly Bites

PubMed Central

Sima, Michal; Ferencova, Blanka; Warburg, Alon; Rohousova, Iva; Volf, Petr

2016-01-01

Background Certain salivary proteins of phlebotomine sand flies injected into the host skin during blood-feeding are highly antigenic and elicit strong antibody-mediated immune responses in repeatedly-exposed hosts. These antibodies can be measured by enzyme-linked immuno sorbent assays (ELISAs) using salivary gland homogenates (SGHs) as the source of antigens and serve as a markers for exposure to biting sand flies. Large-scale screening for anti-sand fly saliva antibodies requires replacement of SGH with recombinant salivary proteins. In East Africa, Phlebotomus orientalis is the main vector of Leishmania donovani, a trypanosomatid parasite causing visceral leishmaniasis. We tested recombinant salivary proteins derived from Ph. orientalis saliva to study exposure of domestic animals to this sand fly species. Methodology/Principal Findings Antigenic salivary proteins from Ph. orientalis were identified by immunoblot and mass spectrometry. Recombinant apyrase rPorSP15, yellow-related protein rPorSP24, ParSP25-like protein rPorSP65, D7-related protein rPorSP67, and antigen 5-related protein rPorSP76 were tested using ELISA with sera of domestic animals from L. donovani foci in Ethiopia where Ph. orientalis is present. Our results highlighted recombinant yellow-related protein rPorSP24 as the most promising antigen, displaying a high positive correlation coefficient as well as good sensitivity and specificity when compared to SGH. This recombinant protein was the most suitable one for testing sera of dogs, sheep, and goats. In addition, a different antigen, rPorSP65 was found efficacious for testing canine sera. Conclusions/Significance Recombinant salivary proteins of Ph. orientalis, specifically rPorSP24, were shown to successfully substitute SGH in serological experiments to measure exposure of domestic animals to Ph. orientalis, the vector of L. donovani. The results suggest that rPorSP24 might be a suitable antigen for detecting anti-Ph. orientalis antibody-mediated reactions also in other host species. PMID:26986566

Recombinant Salivary Proteins of Phlebotomus orientalis are Suitable Antigens to Measure Exposure of Domestic Animals to Sand Fly Bites.

PubMed

Sima, Michal; Ferencova, Blanka; Warburg, Alon; Rohousova, Iva; Volf, Petr

2016-03-01

Certain salivary proteins of phlebotomine sand flies injected into the host skin during blood-feeding are highly antigenic and elicit strong antibody-mediated immune responses in repeatedly-exposed hosts. These antibodies can be measured by enzyme-linked immuno sorbent assays (ELISAs) using salivary gland homogenates (SGHs) as the source of antigens and serve as a markers for exposure to biting sand flies. Large-scale screening for anti-sand fly saliva antibodies requires replacement of SGH with recombinant salivary proteins. In East Africa, Phlebotomus orientalis is the main vector of Leishmania donovani, a trypanosomatid parasite causing visceral leishmaniasis. We tested recombinant salivary proteins derived from Ph. orientalis saliva to study exposure of domestic animals to this sand fly species. Antigenic salivary proteins from Ph. orientalis were identified by immunoblot and mass spectrometry. Recombinant apyrase rPorSP15, yellow-related protein rPorSP24, ParSP25-like protein rPorSP65, D7-related protein rPorSP67, and antigen 5-related protein rPorSP76 were tested using ELISA with sera of domestic animals from L. donovani foci in Ethiopia where Ph. orientalis is present. Our results highlighted recombinant yellow-related protein rPorSP24 as the most promising antigen, displaying a high positive correlation coefficient as well as good sensitivity and specificity when compared to SGH. This recombinant protein was the most suitable one for testing sera of dogs, sheep, and goats. In addition, a different antigen, rPorSP65 was found efficacious for testing canine sera. Recombinant salivary proteins of Ph. orientalis, specifically rPorSP24, were shown to successfully substitute SGH in serological experiments to measure exposure of domestic animals to Ph. orientalis, the vector of L. donovani. The results suggest that rPorSP24 might be a suitable antigen for detecting anti-Ph. orientalis antibody-mediated reactions also in other host species.

"Spider"-shaped porphyrins with conjugated pyridyl anchoring groups as efficient sensitizers for dye-sensitized solar cells.

PubMed

Stangel, Christina; Bagaki, Anthi; Angaridis, Panagiotis A; Charalambidis, Georgios; Sharma, Ganesh D; Coutsolelos, Athanasios G

2014-11-17

Two novel "spider-shaped" porphyrins, meso-tetraaryl-substituted 1PV-Por and zinc-metalated 1PV-Zn-Por, bearing four oligo(p-phenylenevinylene) (oPPV) pyridyl groups with long dodecyloxy chains on the phenyl groups, have been synthesized. The presence of four pyridyl groups in both porphyrins, which allow them to act as anchoring groups upon coordination to various Lewis acid sites, the conjugated oPPV bridges, which offer the possibility of electronic communication between the porphyrin core and the pyridyl groups, and the dodecyloxy groups, which offer the advantage of high solubility in a variety of organic solvents of different polarities and could prevent porphyrin aggregation, renders porphyrins 1PV-Por and 1PV-Zn-Por very promising sensitizers for dye-sensitized solar cells (DSSCs). Photophysical measurements, together with electrochemistry experiments and density functional theory calculations, suggest that both porphyrins have frontier molecular orbital energy levels that favor electron injection and dye regeneration in DSSCs. Solar cells sensitized by 1PV-Por and 1PV-Zn-Por were fabricated, and it was found that they show power conversion efficiencies (PCEs) of 3.28 and 5.12%, respectively. Photovoltaic measurements (J-V curves) together with incident photon-to-electron conversion efficiency spectra of the two cells reveal that the higher PCE value of the DSSC based on 1PV-Zn-Por is ascribed to higher short-circuit current (Jsc), open-circuit voltage (Voc), and dye loading values. Emission spectra and electrochemistry experiments suggest a greater driving force for injection of the photogenerated electrons into the TiO2 conduction band for 1PV-Zn-Por rather than its free-base analogue. Furthermore, electrochemical impedance spectroscopy measurements prove that the utilization of 1PV-Zn-Por as a sensitizer offers a high charge recombination resistance and, therefore, leads to a longer electron lifetime.

System design description for portable 1,000 CFM exhauster Skids POR-007/Skid E and POR-008/Skid F

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, O.D.

1998-07-25

The primary purpose of the two 1,000 CFM Exhauster Skids, POR-007-SKID E and POR-008-SKID F, is to provide backup to the waste tank primary ventilation systems for tanks 241-C-106 and 241-AY-102, and the AY-102 annulus in the event of a failure during the sluicing of tank 241-C-106 and subsequent transfer of sluiced waste to 241-AY-102. This redundancy is required since both of the tank ventilation systems have been declared as Safety Class systems.

Prognosis and cost-effectiveness of IVF in poor responders according to the Bologna Criteria.

PubMed

Busnelli, Andrea; Somigliana, Edgardo

2018-02-01

Poor ovarian response (POR) to controlled ovarian hyperstimulation for in vitro fertilization (IVF) is one of the most challenging issue in the field of reproductive medicine. However, even if improving IVF outcome in poor responders (PORs) represents a main priority, the lack of a unique definition of POR has hampered research in this area. In order to overcome this impediment, an ESHRE Campus Workshop was organized in Bologna in 2010 and reached a consensus on the criteria for the diagnosis of POR ("Bologna Criteria"). In this review we aimed to estimate the prognostic potential of the ESHRE definition, to elucidate its possible weaknesses and to analyze the economic aspects of IVF in a population of poor responders (PORs). Available evidence confirmed that the Bologna criteria are able to select a population with a poor IVF prognosis thus supporting their validity. Nonetheless, different aspects of the definition have been criticized. The main points of debate concern the homogeneity of the population identified, the cut-off values chosen for the ovarian reserve tests and the risks factors other than age associated with POR. Data concerning the economic profile of IVF in PORs are scanty. The only published study on the argument showed that IVF in these cases is not cost-effective. However, considering the potential substantial impact of cost-effectiveness analyses on public health policies, there is the need for further and independent validations.

An ortholog of farA of Aspergillus nidulans is implicated in the transcriptional activation of genes involved in fatty acid utilization in the yeast Yarrowia lipolytica

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poopanitpan, Napapol; Kobayashi, Satoshi; Fukuda, Ryouichi

2010-11-26

Research highlights: {yields} POR1 is a Yarrowia lipolytica ortholog of farA involved in fatty acid response in A. nidulans. {yields} Deletion of POR1 caused growth defects on fatty acids. {yields} {Delta}por1 strain exhibited defects in the induction of genes involved in fatty acid utilization. -- Abstract: The yeast Yarrowia lipolytica effectively utilizes hydrophobic substrates such as fatty acids and n-alkanes. To identify a gene(s) regulating fatty acid utilization in Y. lipolytica, we first studied homologous genes to OAF1 and PIP2 of Saccharomyces cerevisiae, but their disruption did not change growth on oleic acid at all. We next characterized a Y.more » lipolytica gene, POR1 (primary oleate regulator 1), an ortholog of farA encoding a transcriptional activator that regulates fatty acid utilization in Aspergillus nidulans. The deletion mutant of POR1 was defective in the growth on various fatty acids, but not on glucose, glycerol, or n-hexadecane. It exhibited slight defect on n-decane. The transcriptional induction of genes involved in {beta}-oxidation and peroxisome proliferation by oleate was distinctly diminished in the {Delta}por1 strains. These data suggest that POR1 encodes a transcriptional activator widely regulating fatty acid metabolism in Y. lipolytica.« less

76 FR 24857 - Fresh Garlic From the People's Republic of China: Preliminary Intent To Rescind New Shipper Reviews

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-03

... sales are not bona fide. As such, we are preliminarily rescinding the NSR for Shenzhen Bainong and... sale or entry during the original, unextended POR, and therefore we are preliminarily rescinding the...-annual NSR POR. When the sale of the subject merchandise occurs within the POR specified by the...

Hospitalization costs of severe bacterial pneumonia in children: comparative analysis considering different costing methods.

PubMed

Nunes, Sheila Elke Araujo; Minamisava, Ruth; Vieira, Maria Aparecida da Silva; Itria, Alexander; Pessoa, Vicente Porfirio; Andrade, Ana Lúcia Sampaio Sgambatti de; Toscano, Cristiana Maria

2017-01-01

To determine and compare hospitalization costs of bacterial community-acquired pneumonia cases via different costing methods under the Brazilian Public Unified Health System perspective. Cost-of-illness study based on primary data collected from a sample of 59 children aged between 28 days and 35 months and hospitalized due to bacterial pneumonia. Direct medical and non-medical costs were considered and three costing methods employed: micro-costing based on medical record review, micro-costing based on therapeutic guidelines and gross-costing based on the Brazilian Public Unified Health System reimbursement rates. Costs estimates obtained via different methods were compared using the Friedman test. Cost estimates of inpatient cases of severe pneumonia amounted to R$ 780,70/$Int. 858.7 (medical record review), R$ 641,90/$Int. 706.90 (therapeutic guidelines) and R$ 594,80/$Int. 654.28 (Brazilian Public Unified Health System reimbursement rates). Costs estimated via micro-costing (medical record review or therapeutic guidelines) did not differ significantly (p=0.405), while estimates based on reimbursement rates were significantly lower compared to estimates based on therapeutic guidelines (p<0.001) or record review (p=0.006). Brazilian Public Unified Health System costs estimated via different costing methods differ significantly, with gross-costing yielding lower cost estimates. Given costs estimated by different micro-costing methods are similar and costing methods based on therapeutic guidelines are easier to apply and less expensive, this method may be a valuable alternative for estimation of hospitalization costs of bacterial community-acquired pneumonia in children. Determinar e comparar custos hospitalares no tratamento da pneumonia bacteriana adquirida na comunidade por diferentes metodologias de custeio, na perspectiva do Sistema Único de Saúde. Estudo de custo, com coleta de dados primários de uma amostra de 59 crianças com 28 dias a 35 meses de idade hospitalizadas por pneumonia bacteriana. Foram considerados custos diretos médicos e não médicos. Três metodologias de custeio foram utilizadas: microcusteio por revisão de prontuários, microcusteio considerando diretriz terapêutica e macrocusteio por ressarcimento do Sistema Único de Saúde. Os custos estimados pelas diferentes metodologias foram comparados utilizando o teste de Friedman. Os custos hospitalares de crianças com pneumonia grave foram R$ 780,70 ($Int. 858.7) por revisão de prontuários, R$ 641,90 ($Int. 706.90) por diretriz terapêutica e R$ 594,80 ($Int. 654.28) por ressarcimento do Sistema Único de Saúde, respectivamente. A utilização de metodologias de microcusteio (revisão de prontuários e diretriz) resultou em estimativas de custos equivalentes (p=0,405), enquanto o custo estimado por ressarcimento foi significativamente menor do que aqueles estimados por diretriz (p<0,001) e por revisão de prontuário (p=0,006), sendo, assim, significativamente diferentes. Na perspectiva do Sistema Único de Saúde, existe diferença significativa nos custos estimados quando se utilizam diferentes metodologias, sendo a estimativa por ressarcimento a que resulta em valores menores. Considerando que não há diferença nos valores de custos estimados por diferentes metodologias de microcusteio, a metodologia de custeio por diretriz, de mais fácil e rápida execução, é uma alternativa válida para estimativa de custos de hospitalização por pneumonias bacterianas em crianças.

Evidence for the bacterial origin of genes encoding fermentation enzymes of the amitochondriate protozoan parasite Entamoeba histolytica.

PubMed

Rosenthal, B; Mai, Z; Caplivski, D; Ghosh, S; de la Vega, H; Graf, T; Samuelson, J

1997-06-01

Entamoeba histolytica is an amitochondriate protozoan parasite with numerous bacterium-like fermentation enzymes including the pyruvate:ferredoxin oxidoreductase (POR), ferredoxin (FD), and alcohol dehydrogenase E (ADHE). The goal of this study was to determine whether the genes encoding these cytosolic E. histolytica fermentation enzymes might derive from a bacterium by horizontal transfer, as has previously been suggested for E. histolytica genes encoding heat shock protein 60, nicotinamide nucleotide transhydrogenase, and superoxide dismutase. In this study, the E. histolytica por gene and the adhE gene of a second amitochondriate protozoan parasite, Giardia lamblia, were sequenced, and their phylogenetic positions were estimated in relation to POR, ADHE, and FD cloned from eukaryotic and eubacterial organisms. The E. histolytica por gene encodes a 1,620-amino-acid peptide that contained conserved iron-sulfur- and thiamine pyrophosphate-binding sites. The predicted E. histolytica POR showed fewer positional identities to the POR of G. lamblia (34%) than to the POR of the enterobacterium Klebsiella pneumoniae (49%), the cyanobacterium Anabaena sp. (44%), and the protozoan Trichomonas vaginalis (46%), which targets its POR to anaerobic organelles called hydrogenosomes. Maximum-likelihood, neighbor-joining, and parsimony analyses also suggested as less likely E. histolytica POR sharing more recent common ancestry with G. lamblia POR than with POR of bacteria and the T. vaginalis hydrogenosome. The G. lamblia adhE encodes an 888-amino-acid fusion peptide with an aldehyde dehydrogenase at its amino half and an iron-dependent (class 3) ADH at its carboxy half. The predicted G. lamblia ADHE showed extensive positional identities to ADHE of Escherichia coli (49%), Clostridium acetobutylicum (44%), and E. histolytica (43%) and lesser identities to the class 3 ADH of eubacteria and yeast (19 to 36%). Phylogenetic analyses inferred a closer relationship of the E. histolytica ADHE to bacterial ADHE than to the G. lamblia ADHE. The 6-kDa FD of E. histolytica and G. lamblia were most similar to those of the archaebacterium Methanosarcina barkeri and the delta-purple bacterium Desulfovibrio desulfuricans, respectively, while the 12-kDa FD of the T. vaginalis hydrogenosome was most similar to the 12-kDa FD of gamma-purple bacterium Pseudomonas putida. E. histolytica genes (and probably G. lamblia genes) encoding fermentation enzymes therefore likely derive from bacteria by horizontal transfer, although it is not clear from which bacteria these amebic genes derive. These are the first nonorganellar fermentation enzymes of eukaryotes implicated to have derived from bacteria.

Management of post-operative Crohn's disease in 2017: where do we go from here?

PubMed

Nguyen, Vu; Kanth, Rajan; Gazo, Joshua; Sorrentino, Dario

2016-11-01

Postoperative recurrence (POR) of Crohn's disease is common after surgical resection. How to best manage POR remains uncertain. Areas covered: In this review, we will first describe the natural course and the best modalities to diagnose this surgical sequela. We will then focus on the potential risk factors for relapse and highlight the main shortcomings in the current study designs and endoscopic and clinical scoring systems, which may partly explain the unexpected outcomes of recent clinical trials. Finally, we will propose a strategy to address the management of POR. Expert commentary: Anti-tumor necrosis factor (Anti-TNF) agents are the most effective therapy to prevent POR in Crohn's disease. Patient risk stratification and active monitoring with scheduled ileocolonoscopy are cornerstones of optimal POR management. Further studies are needed to address areas of uncertainty including timing and duration of therapy and the role of therapeutic drug monitoring in this setting.

Developing a military nurse scientist program of research: A military women's health exemplar.

PubMed

Trego, Lori Lyn

Developing a feasible, fundable, and sustainable program of research (POR) is an essential career goal in research. Nurse scientists can lay the foundation for a salient POR as early as during their doctoral studies. The ensuing years of postdoctoral experiences are informative as they expand their research skills and knowledge around their research area of interest. Following graduation from a doctoral research program, novice military nurse scientists (MNS) are placed in positions that are conducive to fostering a POR. Military organizational support and the rich experiences of peers and mentors facilitate early career development of MNS. The purpose of this article is to present a conceptual framework for research career development of the novice MNS. Using an exemplar POR in military women's health, the concepts are operationalized to illustrate how the military environment enhances the development of a successful POR. Copyright © 2017 Elsevier Inc. All rights reserved.

Influence of the doping type and level on the morphology of porous Si formed by galvanic etching

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pyatilova, O. V., E-mail: 5ilova87@gmail.com; Gavrilov, S. A.; Shilyaeva, Yu. I.

The formation of porous silicon (por-Si) layers by the galvanic etching of single-crystal Si samples (doped with boron or phosphorus) in an HF/C{sub 2}H{sub 5}OH/H{sub 2}O{sub 2} solution is investigated. The por-Si layers are analyzed by the capillary condensation of nitrogen and scanning electron microscopy (SEM). The dependences of the morphological characteristics of por-Si (pore diameter, specific surface area, pore volume, and thickness of the pore walls), which determine the por-Si combustion kinetics, on the dopant type and initial wafer resistivity are established.

First example of a modular porphyrinoid assembly capable of stabilizing different metal ions in a single molecular scaffold.

PubMed

Murugavel, Muthuchamy; Reddy, R V Ramana; Dey, Dhananjay; Sankar, Jeyaraman

2015-10-05

We report the synthesis and characterization of porphyrin-corrole-porphyrin (Por-Cor-Por) hybrids directly linked at the meso-meso positions for the first time. The stability and solubility of the trimer are carefully balanced by adding electron-withdrawing substituents to the corrole ring and sterically bulky groups on the porphyrins. The new hybrids are capable of stabilizing more than one metal ion in a single molecular scaffold. The versatility of the triad has been demonstrated by successfully stabilizing homo- (Ni) and heterotrinuclear (Ni-Cu-Ni) coordination motifs. The solid-state structure of the NiPor-CuCor-PorNi hybrid was revealed by single-crystal X-ray diffraction studies. The Ni(II) porphyrins are significantly ruffled and tilted by 83° from the plane of corrole. The robustness of the synthesized hybrids was reflected in the electrochemical investigations and the redox behaviour of the hybrids show that the oxidation processes are mostly corrole-centred. In particular it is worth noting that the Por-Cor-Por hybrid can further be manipulated due to the presence of substituent-free meso-positions on both the terminals. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Multiple active site residues are important for photochemical efficiency in the light-activated enzyme protochlorophyllide oxidoreductase (POR).

PubMed

Menon, Binuraj R K; Hardman, Samantha J O; Scrutton, Nigel S; Heyes, Derren J

2016-08-01

Protochlorophyllide oxidoreductase (POR) catalyzes the light-driven reduction of protochlorophyllide (Pchlide), an essential, regulatory step in chlorophyll biosynthesis. The unique requirement of the enzyme for light has provided the opportunity to investigate how light energy can be harnessed to power biological catalysis and enzyme dynamics. Excited state interactions between the Pchlide molecule and the protein are known to drive the subsequent reaction chemistry. However, the structural features of POR and active site residues that are important for photochemistry and catalysis are currently unknown, because there is no crystal structure for POR. Here, we have used static and time-resolved spectroscopic measurements of a number of active site variants to study the role of a number of residues, which are located in the proposed NADPH/Pchlide binding site based on previous homology models, in the reaction mechanism of POR. Our findings, which are interpreted in the context of a new improved structural model, have identified several residues that are predicted to interact with the coenzyme or substrate. Several of the POR variants have a profound effect on the photochemistry, suggesting that multiple residues are important in stabilizing the excited state required for catalysis. Our work offers insight into how the POR active site geometry is finely tuned by multiple active site residues to support enzyme-mediated photochemistry and reduction of Pchlide, both of which are crucial to the existence of life on Earth. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Weathering resistance of thin plasma polymer films on pre-coated steel =

NASA Astrophysics Data System (ADS)

Serra, Ricardo Gil Henriques

O trabalho apresentado teve origem no projecto de investigacao “Tailored Thin Plasma Polymers Films for Surface Engineering of Coil Coated Steel”, financiado pelo Programa Europeu ECSC Steel Research. Sistemas de aco galvanizado pre-pintado em banda a base de poliester e poliuretano foram submetidos a um processo de polimerizacao por plasma onde um filme fino foi depositado de modo a modificar as propriedades de superficie. Foram usados reactores de catodo oco, microondas e radio frequencia para a deposicao do polimero fino. Os sistemas preparados foram analisados de modo a verificar a influencia do processo de polimerizacao por plasma na alteracao das propriedades barreira dos sistemas pre-pintados em banda. Foi estudado o efeito dos diferentes passos do processo de polimerizacao por plasma, bem como o efeito de diferentes variaveis operatorias. A mistura precursora foi variada de modo a modificar as propriedades da superficie de modo a poder vir a obter maior hidrofobicidade, maior resistencia a marcas digitais, bem como maior facilidade de limpeza. Os testes foram conduzidos em solucao de NaCl 0,5 M. Para o trabalho foram usadas tecnicas de analise da morfologia da superficie como Microscopia de Forca Atomica e Microscopia Electronica de Varrimento. As propriedades electroquimicas dos sistemas foram estudadas por Espectroscopia de Impedancia Electroquimica. A estrutura dos filmes gerados no processo de polimerizacao por plasma foi caracterizada por Microscopia de Transmissao Electronica. A modificacao das propriedades opticas devido ao processo de polimerizacao por plasma foi tambem obtida.

Structural and functional probing of PorZ, an essential bacterial surface component of the type-IX secretion system of human oral-microbiomic Porphyromonas gingivalis.

PubMed Central

Lasica, Anna M.; Goulas, Theodoros; Mizgalska, Danuta; Zhou, Xiaoyan; de Diego, Iñaki; Ksiazek, Mirosław; Madej, Mariusz; Guo, Yonghua; Guevara, Tibisay; Nowak, Magdalena; Potempa, Barbara; Goel, Apoorv; Sztukowska, Maryta; Prabhakar, Apurva T.; Bzowska, Monika; Widziolek, Magdalena; Thøgersen, Ida B.; Enghild, Jan J.; Simonian, Mary; Kulczyk, Arkadiusz W.; Nguyen, Ky-Anh; Potempa, Jan; Gomis-Rüth, F. Xavier

2016-01-01

Porphyromonas gingivalis is a member of the human oral microbiome abundant in dysbiosis and implicated in the pathogenesis of periodontal (gum) disease. It employs a newly described type-IX secretion system (T9SS) for secretion of virulence factors. Cargo proteins destined for secretion through T9SS carry a recognition signal in the conserved C-terminal domain (CTD), which is removed by sortase PorU during translocation. Here, we identified a novel component of T9SS, PorZ, which is essential for surface exposure of PorU and posttranslational modification of T9SS cargo proteins. These include maturation of enzyme precursors, CTD removal and attachment of anionic lipopolysaccharide for anchorage in the outer membrane. The crystal structure of PorZ revealed two β-propeller domains and a C-terminal β-sandwich domain, which conforms to the canonical CTD architecture. We further documented that PorZ is itself transported to the cell surface via T9SS as a full-length protein with its CTD intact, independently of the presence or activity of PorU. Taken together, our results shed light on the architecture and possible function of a novel component of the T9SS. Knowledge of how T9SS operates will contribute to our understanding of protein secretion as part of host-microbiome interactions by dysbiotic members of the human oral cavity. PMID:27883039

Association between arsenic exposure from drinking water and proteinuria: results from the Health Effects of Arsenic Longitudinal Study

PubMed Central

Chen, Yu; Parvez, Faruque; Liu, Mengling; Pesola, Gene R; Gamble, Mary V; Slavkovich, Vesna; Islam, Tariqul; Ahmed, Alauddin; Hasan, Rabiul; Graziano, Joseph H; Ahsan, Habibul

2011-01-01

Background Proteinuria has been recognized as a marker for an increased risk of chronic renal disease. It is unclear whether arsenic (As) exposure from drinking water is associated with proteinuria. Methods We evaluated the association between As exposure from drinking water and proteinuria in 11 122 participants in the Health Effects of Arsenic Longitudinal Study (HEALS). Proteinuria was detected by urinary dipstick tests at baseline and at 2-year intervals. As exposure variables included baseline well As and changes in urinary As during follow-up modelled as time-dependent variables in the analyses. Results At baseline, well As was positively related to prevalence of proteinuria; prevalence odds ratios (PORs) for proteinuria in increasing quintiles of well As (≤7, 8–39, 40–91, 92–179 and 180–864 µg/l) were 1.00 (ref), POR 0.99 [95% confidence interval (CI) 0.77–1.27], POR 1.23 (95% CI 0.97–1.57), POR 1.50 (95% CI 1.18–1.89) and POR 1.59 (95% CI 1.26–2.00) (P for trend <0.01). Hazard ratios for incidence of proteinuria were POR 0.83 (95% CI 0.67–1.03) and POR 0.91 (95% CI 0.74–1.12) for participants with a decreasing level of >70 and 17–70 µg/l in urinary As over time, respectively, and were POR 1.17 (95% CI 0.97–1.42) and POR 1.42 (95% CI 1.16–1.73) for participants with an increasing level of 16–68 and >68 µg/l in urinary As over time, respectively, compared with the group with relatively little changes in urinary As as the reference group (urinary As −16 to 15 µg/l). Conclusion The findings suggest that there are adverse effects of As exposure on the risk of proteinuria and the effects are modifiable by recent changes in As exposure. PMID:21343184

Co-infection of classic swine H1N1 influenza virus in pigs persistently infected with porcine rubulavirus.

PubMed

Rivera-Benitez, José Francisco; De la Luz-Armendáriz, Jazmín; Saavedra-Montañez, Manuel; Jasso-Escutia, Miguel Ángel; Sánchez-Betancourt, Ivan; Pérez-Torres, Armando; Reyes-Leyva, Julio; Hernández, Jesús; Martínez-Lara, Atalo; Ramírez-Mendoza, Humberto

2016-02-29

Porcine rubulavirus (PorPV) and swine influenza virus infection causes respiratory disease in pigs. PorPV persistent infection could facilitate the establishment of secondary infections. The aim of this study was to analyse the pathogenicity of classic swine H1N1 influenza virus (swH1N1) in growing pigs persistently infected with porcine rubulavirus. Conventional six-week-old pigs were intranasally inoculated with PorPV, swH1N1, or PorPV/swH1N1. A mock-infected group was included. The co-infection with swH1N1 was at 44 days post-infection (DPI), right after clinical signs of PorPV infection had stopped. The pigs of the co-infection group presented an increase of clinical signs compared to the simple infection groups. In all infected groups, the most recurrent lung lesion was hyperplasia of the bronchiolar-associated lymphoid tissue and interstitial pneumonia. By means of immunohistochemical evaluation it was possible to demonstrate the presence of the two viral agents infecting simultaneously the bronchiolar epithelium. Viral excretion of PorPV in nasal and oral fluid was recorded at 28 and 52 DPI, respectively. PorPV persisted in several samples from respiratory tissues (RT), secondary lymphoid organs (SLO), and bronchoalveolar lavage fluid (BALF). For swH1N1, the viral excretion in nasal fluids was significantly higher in single-infected swH1N1 pigs than in the co-infected group. However, the co-infection group exhibited an increase in the presence of swH1N1 in RT, SLO, and BALF at two days after co-infection. In conclusion, the results obtained confirm an increase in the clinical signs of infection, and PorPV was observed to impact the spread of swH1N1 in analysed tissues in the early stage of co-infection, although viral shedding was not enhanced. In the present study, the interaction of swH1N1 infection is demonstrated in pigs persistently infected with PorPV. Copyright © 2016 Elsevier B.V. All rights reserved.

Estimación de pequeñas perturbaciones en satélites geocéntricos como un problema inverso

NASA Astrophysics Data System (ADS)

Zadunaisky, P. E.

El movimiento geocéntrico de un satélite artificial es simulado automáticamente por un sistema de ecuaciones diferenciales de segundo orden que incluyen dos funciones perturbadoras. La primera representa el segundo término del potencial gravitatorio de la Tierra y la segunda corresponde al frenado atmosférico. Asumiendo como conocidas, por hipótesis o por mediciones, la posición y velocidad del satélite en instantes sucesivos se estiman las perturbaciones a intervalos sucesivos por un método determinístico. Para ilustrar el método y comprobar la precisión de nuestros resultados hemos simulado dos ejemplos incluyendo valores conocidos de las perturbaciones que luego comparamos con los resultados de nuestro método. El método puede aplicarse por ejemplo para el intervalo de una revolución satelital lo cual permitiría el diseño inmediato de una maniobra correctiva de la órbita satelital.

AnatomicalTerms.info: heading for an online solution to the anatomical synonym problem hurdles in data-reuse from the Terminologia Anatomica and the foundational model of anatomy and potentials for future development.

PubMed

Gobée, O Paul; Jansma, Daniël; DeRuiter, Marco C

2011-10-01

The many synonyms for anatomical structures confuse medical students and complicate medical communication. Easily accessible translations would alleviate this problem. None of the presently available resources-Terminologia Anatomica (TA), digital terminologies such as the Foundational Model of Anatomy (FMA), and websites-are fully satisfactory to this aim. Internet technologies offer new possibilities to solve the problem. Several authors have called for an online TA. An online translation resource should be easily accessible, user-friendly, comprehensive, expandable, and its quality determinable. As first step towards this goal, we built a translation website that we named www.AnatomicalTerms.info, based on the database of the FMA. It translates between English, Latin, eponyms, and to a lesser extent other languages, and presently contains over 31,000 terms for 7,250 structures, covering 95% of TA. In addition, it automatically presents searches for images, documents and anatomical variations regarding the sought structure. Several terminological and conceptual issues were encountered in transferring data from TA and FMA into AnatomicalTerms.info, resultant from these resources' different set-ups (paper versus digital) and targets (machine versus human-user). To the best of our knowledge, AnatomicalTerms.info is unique in its combination of user-friendliness and comprehensiveness. As next step, wiki-like expandability will be added to enable open contribution of clinical synonyms and terms in different languages. Specific quality measures will be taken to strike a balance between open contribution and quality assurance. AnatomicalTerms.info's mechanism that "translates" terms to structures furthermore may enhance targeted searching by linking images, descriptions, and other anatomical resources to the structures. Copyright © 2011 Wiley-Liss, Inc.

Drug residues in urban water: A database for ecotoxicological risk management.

PubMed

Destrieux, Doriane; Laurent, François; Budzinski, Hélène; Pedelucq, Julie; Vervier, Philippe; Gerino, Magali

2017-12-31

Human-use drug residues (DR) are only partially eliminated by waste water treatment plants (WWTPs), so that residual amounts can reach natural waters and cause environmental hazards. In order to properly manage these hazards in the aquatic environment, a database is made available that integrates the concentration ranges for DR, which cause adverse effects for aquatic organisms, and the temporal variations of the ecotoxicological risks. To implement this database for the ecotoxicological risk assessment (ERA database), the required information for each DR is the predicted no effect concentrations (PNECs), along with the predicted environmental concentrations (PECs). The risk assessment is based on the ratio between the PNECs and the PECs. Adverse effect data or PNECs have been found in the publicly available literature for 45 substances. These ecotoxicity test data have been extracted from 125 different sources. This ERA database contains 1157 adverse effect data and 287 PNECs. The efficiency of this ERA database was tested with a data set coming from a simultaneous survey of WWTPs and the natural environment. In this data set, 26 DR were searched for in two WWTPs and in the river. On five sampling dates, concentrations measured in the river for 10 DR could pose environmental problems of which 7 were measured only downstream of WWTP outlets. From scientific literature and measurements, data implementation with unit homogenisation in a single database facilitates the actual ecotoxicological risk assessment, and may be useful for further risk coming from data arising from the future field survey. Moreover, the accumulation of a large ecotoxicity data set in a single database should not only improve knowledge of higher risk molecules but also supply an objective tool to help the rapid and efficient evaluation of the risk. Copyright © 2017 Elsevier B.V. All rights reserved.

Jaguar Densities across Human-Dominated Landscapes in Colombia: The Contribution of Unprotected Areas to Long Term Conservation

PubMed Central

Boron, Valeria; Tzanopoulos, Joseph; Gallo, Jenny; Barragan, Jorge; Jaimes-Rodriguez, Laura; Schaller, George; Payán, Esteban

2016-01-01

Large carnivores such as jaguars (Panthera onca) are species of conservation concern because they are suffering population declines and are keystone species in their ecosystems. Their large area requirements imply that unprotected and ever-increasing agricultural regions can be important habitats as they allow connectivity and dispersal among core protected areas. Yet information on jaguar densities across unprotected landscapes it is still scarce and crucially needed to assist management and range-wide conservation strategies. Our study provides the first jaguar density estimates of Colombia in agricultural regions which included cattle ranching, the main land use in the country, and oil palm cultivation, an increasing land use across the Neotropics. We used camera trapping across two agricultural landscapes located in the Magdalena River valley and in the Colombian llanos (47–53 stations respectively; >2000 trap nights at both sites) and classic and spatially explicit capture-recapture models with the sex of individuals as a covariate. Density estimates were 2.52±0.46–3.15±1.08 adults/100 km2 in the Magdalena valley, whereas 1.12±0.13–2.19±0.99 adults/100 km2 in the Colombian llanos, depending on analysis used. We suggest that jaguars are able to live across unprotected human-use areas and co-exist with agricultural landscapes including oil-palm plantations if natural areas and riparian habitats persist in the landscape and hunting of both jaguar and prey is limited. In the face of an expanding agriculture across the tropics we recommend land-use planning, adequate incentives, regulations, and good agricultural practices for range-wide jaguar connectivity and survival. PMID:27144280

El Estado de los Bosques de Puerto Rico, 2003

Treesearch

Thomas J. Brandeis; Eileen H. Helmer; Sonja N. Oswalt

2003-01-01

La cobertura forestal de Puerto Rico sigue aumentando y ahora asciende a un 57 por ciento en la isla de Puerto Rico, 85 por ciento en Vieques y 88 por ciento en Culebra. Los bosques subtropicales secos ocupan 50 346 ha, 6832 ha, 2591 ha y 6217 ha en las islas de Puerto Rico, Vieques, Culebra y Mona, respectivamente. El bosque subtropical húmedo, la zona de vida...

The role of galectin-1 in in vitro and in vivo photodynamic therapy with a galactodendritic porphyrin.

PubMed

Pereira, Patrícia M R; Silva, Sandrina; Ramalho, José S; Gomes, Célia M; Girão, Henrique; Cavaleiro, José A S; Ribeiro, Carlos A F; Tomé, João P C; Fernandes, Rosa

2016-11-01

Conventional photodynamic agents used in clinic are porphyrin-based photosensitizers. However, they have low tumour selectivity, which may induce unwanted side-effects and damage to healthy tissues. In this study, we used a porphyrin with dendritic units of galactose (PorGal 8 ) developed by us, which can target the galactose-binding protein, galectin-1, known to be overexpressed in many tumour tissues. In vitro and in vivo studies had been conducted for the validation of PorGal 8 effectiveness. We showed a specific uptake of PorGal 8 and induction of apoptotic cell death by generating oxidative stress and alterations in the cytoskeleton of bladder cancer cells overexpressing galectin-1. We further validated the photodynamic efficiency of PorGal 8 in athymic nude mice (Balb/c nu/nu) bearing subcutaneously implanted luciferase-positive bladder cancer xenografts, overexpressing galectin-1 protein. PorGal 8 (5 μmol/kg, intraperitoneal), injected 24 h before light delivery (50.4 J/cm 2 ), inhibited tumour growth. We conclude that the use of PorGal 8 enables selective target and cytotoxicity by photodynamic therapy in cancer cells overexpressing galectin-1, preventing undesired phototoxicity in the surrounding healthy tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

"Power-on resets" in cardiac implantable electronic devices during magnetic resonance imaging.

PubMed

Higgins, John V; Sheldon, Seth H; Watson, Robert E; Dalzell, Connie; Acker, Nancy; Cha, Yong-Mei; Asirvatham, Samuel J; Kapa, Suraj; Felmlee, Joel P; Friedman, Paul A

2015-03-01

Magnetic resonance imaging (MRI) has been safely performed in some patients with cardiac implantable electronic devices (CIEDs) under careful monitoring and prespecified conditions. Pacemaker-dependent patients are often excluded, partly because of the potential for "power-on reset" (PoR), which can lead to a change from asynchronous to inhibited pacing with consequent inhibition of pacing due to electromagnetic interference during MRI. The purpose of this study was to review risk factors for PoR during MRI. A prospective study was performed between January 2008 and May 2013 in patients with CIEDs undergoing clinically indicated MRI. Eligible patients were not pacemaker dependent. Devices were interrogated before and after MRI, programmed to an asynchronous mode or an inhibition mode with tachyarrhythmia therapies turned off, and reprogrammed to their original settings after MRI. MRI scans (n = 256) were performed in 198 patients with non-MRI-conditional CIEDs between 2008 and 2013 (median age 66 years; interquartile range 57-77 years; 59% men). PoR occurred during 9 MRI scans (3.5%) in 8 patients. PoR was more frequent with Medtronic devices than with other generator brands (n = 9/139 vs 0/117 [6% vs 0%]; P = .005). Devices with PoR were all released before 2002 and were implanted from 1999 to 2004. Effects of PoR included a decrease in heart rate during MRI (n = 4) and transient anomalous battery life indication (n = 1). All devices functioned normally after MRI. PoR occurs infrequently but can cause deleterious changes in pacing mode and heart rate. MRI should not be performed in pacemaker-dependent patients with older at-risk generators. Continuous monitoring during MRI is essential because unrecognized PoR may inhibit pacing or accelerate battery depletion due to high pacing output. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Inversor Resonante de Tres Elementos L-LC con Caracteristica Cortocircuitable para Aplicaciones de Calentamiento por Induccion

NASA Astrophysics Data System (ADS)

Espi Huerta, Jose Miguel

Los generadores de calentamiento por induccion son puentes inversores con carga resonante, cuya mision es basicamente crear una corriente sinusoidal de gran amplitud sobre la "bobina de caldeo", que forma parte del tanque resonante. En el interior de esta bobina se introduce la pieza que se desea calentar. EI campo magnetico creado induce corrientes superficiales (corrientes de Foucault) sobre la pieza, que producen su calentamiento. Los tanques resonantes (tambien llamados osciladores) utilizados en la actualidad son el resonante serie y el resonante paralelo. Aunque ya desde hace algun tiempo se vienen construyendo generadores de alta potencia basados en estos dos osciladores, el exito nunca ha. sido completo en ninguno de los dos casos. Tal y como se explica en la introduccion de esta memoria, los puentes inversores utilizados deben operar sobre una carga inductiva (corriente retrasada) para evitar el fenomeno de la recuperacion inversa de sus diodos y la consiguiente ruptura de los transistores. De la restriccion topologica anterior se deduce que el generador paralelo debe conmutar a frecuencias inferiores a la resonancia, y el serie a frecuencias superiores. A esta restriccion topologica hay que unir otra que es exclusiva del calentamiento por induccion: La corriente por la bobina de caldeo debe ser sinusoidal. De no ser asi, resultaria imposible disponer toda la potencia de calentamiento sobre la pieza en el espesor requerido por la aplicacion. Como consecuencia, los inversores no pueden operar por debajo de la frecuencia de resonancia del oscilador, pues en ese caso se amplifican los armonicos de orden superior de la tension/corriente de entrada situados sobre la resonancia, con la consiguiente distorsion de la corriente de salida. La conjuncion de las dos restricciones anteriores obligan al inversor paralelo a funcionar a la frecuencia de resonancia del oscilador. Esto imposibilita un control por variacion de frecuencia, regulandose la potencia desde la seccion de entrada mediante un mayor o menor aporte de corriente al puente. Como consecuencia, la seccion de entrada del paralelo, ya de por si mas voluminosa que lao del serie por el uso de grandes componentes magneticos (bobinas de filtro o de "alisamiento"), result a tambien mas complicada y costosa debido a la necesidad de ser implementada mediante rectificador controlado. Ademas, la regulacion que ofrece el rectificador es pobre, dada su baja frecuencia de conmutacion. En cambio, el circuito serie puede funcionar por encima de la resonancia manteniendo una secuencia de conmutacion sin riesgos de recuperacion inversa y con una corriente de salida practicamente sinusoidal, lo que permite un control de la potencia por variacion de frecuencia. Puesto que la tarea de regulacion se realiza desde el puente inversor, la regulacion resulta mucho mas eficaz y la seccion de entrada se puede implementar mediante un simple rectificador no controlado y un condensador de filtro. (Abstract shortened by UMI.).

Concepciones y concepciones alternativas de estudiantes universitarios/as de biologia y futuros maestros/as de Ciencia de escuela secundaria sobre la teoria de evolucion biologica por seleccion natural

NASA Astrophysics Data System (ADS)

Morales Ramos, Egda M.

La teoria de evolucion biologica (TEB) por seleccion natural es uno de los conceptos unificadores mas importantes del curriculo de Biologia. En Puerto Rico se han hecho pocas investigaciones que abunden sobre las concepciones y concepciones alternativas (CA) que tienen los estudiantes universitarios/as de Biologia y los maestros/as de Ciencia del nivel secundario sobre esta teoria. La politica publica educativa actual establece mediante documentos normativos como los Estandares de contenido y Expectativas de grado del Programa de Ciencias [Puerto Rico Core Standards] la ensenanza de esta teoria. Sin embargo, no se encontraron preguntas sobre la seleccion natural en los ejercicios de practica provistos por el Departamento de Educacion para las pruebas estandarizadas lo cual puede influir para que no se ensene adecuadamente. Las preguntas de investigacion fueron 1. ¿Cuales son las concepciones y concepciones alternativas de estudiantes universitarios/as y de los futuros maestros y maestras de Ciencia sobre la TEB? 2. ¿Cuales conceptos que seleccionan los estudiantes universitarios/as y los futuros maestros y maestras de Ciencia sobre la TEB coinciden con lo aceptado como valido por la comunidad cientifica? y 3. ¿Como comparan las respuestas de la prueba original. v. Entendiendo el cambio biologico que mide concepciones y CA sobre la TEB por seleccion natural, con las de la traducida al idioma espanol? Se utilizo el metodo cuantitativo con un diseno de investigacion transversal por encuesta. La tecnica principal para recopilar los datos fue una prueba con doce items, que formo parte de un instrumento para el cual se recopilaron diversas fuentes de evidencia acerca de su validez. Las muestras estuvieron formadas por 69 estudiantes de Ciencias Naturales y por 16 estudiantes futuros maestros y maestras del nivel secundario de la UPR-RP. Se utilizaron estadisticas descriptivas, analisis de Ji cuadrado y se calcularon los coeficientes alfa de Cronbach y de Spearman. Estos demostraron que la prueba es confiable para medir las concepciones y CA de la TEB por seleccion natural. Aunque los estudiantes escogieron conceptos relacionados con esta teoria, mantienen en sus procesos de razonamiento CA sobre la seleccion natural que no se limitan a la lamarckiana y a la teleologica.

Moléculas orgánicas obtenidas en simulaciones experimentales del medio interestelar.

NASA Astrophysics Data System (ADS)

Muñoz-Caro, Guillermo Manuel

Las nubes moleculares son regiones de formación de estrellas, con temperaturas cinéticas entre 10-50 K y densidades de 103-106 átomos cm-3. Su materia está formada por gas y polvo interestelar. Estas partículas de polvo están cubiertas por una fina capa de hielo, de unos 0.01 μm, que contiene H2O y a menudo CO, CO2, CH3OH y NH3. El hielo es presumiblemente irradiado por fotones ultravioleta y rayos cósmicos en las zonas poco profundas de las nubes moleculares y las regiones circunestelares. En un sistema de vacío, P ˜ 10-7 mbar, simulamos la deposición de hielo a partir de 10 K y la irradiación ultravioleta por medio de una lámpara de descarga de hidrógeno activada con microondas. La evolución del hielo se observa por medio de un espectrómetro infrarrojo. De este modo es posible determinar la composición del hielo observado en el medio interestelar y predecir la presencia de moléculas aún no detectadas en el espacio, que han sido producto del procesamiento del hielo en nuestros experimentos. También es posible calentar el sistema hasta temperatura ambiente para sublimar el hielo depositado. Cuando el hielo ha sido previamente irradiado, se observa un residuo compuesto por moléculas orgánicas complejas, algunas prebióticas, como varios ácidos carboxílicos, aminas, amidas, ésteres y en menor proporción moléculas heterocíclicas y aminoácidos. Algunas de estas moléculas podrían detectarse en estado gaseoso por medio de observaciones milimétricas y de radio. También podrían estar presentes en el polvo cometario, cuyo análisis químico está planeado por las misiones Stardust y Rosetta. Mientras tanto, nuestro grupo está llevando a cabo el análisis de partículas de polvo interplanetario (IDPs), algunas de las cuales pueden ser de origen cometario. Al igual que ocurre con los productos obtenidos por irradiación del hielo en nuestros experimentos, algunas IDPs son ricas en material orgánico que contiene oxígeno.

Prevalence of asthma and chronic obstructive pulmonary disease in Aboriginal and non-Aboriginal populations: A systematic review and meta-analysis of epidemiological studies

PubMed Central

Ospina, Maria B; Voaklander, Donald C; Stickland, Michael K; King, Malcolm; Senthilselvan, Ambikaipakan; Rowe, Brian H

2012-01-01

BACKGROUND: Asthma and chronic obstructive pulmonary disease (COPD) have considerable potential for inequities in diagnosis and treatment, thereby affecting vulnerable groups. OBJECTIVE: To evaluate differences in asthma and COPD prevalence between adult Aboriginal and non-Aboriginal populations. METHODS: MEDLINE, EMBASE, specialized databases and the grey literature up to October 2011 were searched to identify epidemiological studies comparing asthma and COPD prevalence between Aboriginal and non-Aboriginal adult populations. Prevalence ORs (PORs) and 95% CIs were calculated in a random-effects meta-analysis. RESULTS: Of 132 studies, eight contained relevant data. Aboriginal populations included Native Americans, Canadian Aboriginals, Australian Aboriginals and New Zealand Maori. Overall, Aboriginals were more likely to report having asthma than non-Aboriginals (POR 1.41 [95% CI 1.23 to 1.60]), particularly among Canadian Aboriginals (POR 1.80 [95% CI 1.68 to 1.93]), Native Americans (POR 1.41 [95% CI 1.13 to 1.76]) and Maori (POR 1.64 [95% CI 1.40 to 1.91]). Australian Aboriginals were less likely to report asthma (POR 0.49 [95% CI 0.28 to 0.86]). Sex differences in asthma prevalence between Aboriginals and their non-Aboriginal counterparts were not identified. One study compared COPD prevalence between Native and non-Native Americans, with similar rates in both groups (POR 1.08 [95% CI 0.81 to 1.44]). CONCLUSIONS: Differences in asthma prevalence between Aboriginal and non-Aboriginal populations exist in a variety of countries. Studies comparing COPD prevalence between Aboriginal and non-Aboriginal populations are scarce. Further investigation is needed to identify and account for factors associated with respiratory health inequalities among Aboriginal peoples. PMID:23248798

PubMed

Scotta, Ana Verónica; Bongiovanni, Guillermina Azucena; Soria, Elio Andrés

2018-03-21

Antecedentes: Clorpirifos es un pesticida altamente tóxico, que puede producir inmunotoxicidad con efectos deletéreos sobre la salud a nivel mundial. Por otro lado, las plantas americanas pueden tener derivados con actividad protectora e inmunoestimulante. Por lo tanto, debe evaluarse el potencial de estas plantas frente a clorpirifos. Objetivo: Identificar extractos acuosos bioactivos de Lantana grisebachii (LG), Aspidosperma quebracho-blanco (AQ), Peumus boldus (PB), e Ilex paraguariensis (IP), contra la toxicidad de clorpirifos sobre esplenocitos de hembras Balb/c. Materiales y Métodos: Esplenocitos fueron tratados in vitro por 72 horas con 0-35 µg/mL de clorpirifos, 0-100 µg/mL de cada extracto (LG, AQ, PB, IP) y 0-5 µg/mL de concanavalina A. Luego, se midió y analizó estadísticamente viabilidad y muerte celular (tinciones de resazurina y yoduro de propidio), hidroperóxidos, lipoperóxidos (ensayos basados en naranja de xilenol), actividad de la ?-glutamiltranspeptidasa (método de Szasz). Resultados: Clorpirifos redujo la viabilidad celular de forma dosis dependiente, lo que fue contrarrestado por AQ e IP, los que fueron menos activos en las células inducibles por concanavalina A (p<0,05). La toxicidad por clorpirifos implicó la inducción de la ?-glutamiltranspeptidasa con la consecuente reducción de los peróxidos, mientras que AQ y principalmente IP antagonizaron dichas respuestas (p<0,05). Conclusiones: Los extractos de Ilex paraguariensis y Aspidosperma quebracho-blanco protegieron in vitro a los esplenocitos frente a clorpirifos. Este efecto dependió del tipo celular, dado que las células inducibles por concanavalina A fueron más susceptibles a este tóxico.

Empirical Analysis of Using Erasure Coding in Outsourcing Data Storage With Provable Security

DTIC Science & Technology

2016-06-01

the fastest encoding performance among the four tested schemes. We expected to observe that Cauchy Reed-Solomonwould be faster than Reed- Solomon for all...providing recoverability for POR. We survey MDS codes and select Reed- Solomon and Cauchy Reed- Solomon MDS codes to be implemented into a prototype POR...tools providing recoverability for POR. We survey MDS codes and select Reed- Solomon and Cauchy Reed- Solomon MDS codes to be implemented into a

Neuraminidase activity of blue eye disease porcine rubulavirus: Specificity, affinity and inhibition studies.

PubMed

Santos-López, Gerardo; Borraz-Argüello, María T; Márquez-Domínguez, Luis; Flores-Alonso, Juan Carlos; Ramírez-Mendoza, Humberto; Priem, Bernard; Fort, Sébastien; Vallejo-Ruiz, Verónica; Reyes-Leyva, Julio; Herrera-Camacho, Irma

2017-10-01

Porcine rubulavirus (PorPV), also known as La Piedad Michoacan Virus (LPMV) causes encephalitis and reproductive failure in newborn and adult pigs, respectively. The hemagglutinin-neuraminidase (HN) glycoprotein is the most exposed and antigenic of the virus proteins. HN plays central roles in PorPV infection; i.e., it recognizes sialic acid-containing cell receptors that mediate virus attachment and penetration; in addition, its neuraminidase (sialic acid releasing) activity has been proposed as a virulence factor. This work describes the purification and characterization of PorPV HN protein (isolate PAC1). The specificity of neuraminidase is restricted to sialyl(α2,3)lactose (3SL). HN showed typical Michaelis-Menten kinetics with fetuin as substrate (km=0.029μM, Vmax=522.8nmolmin -1 mg -1 ). When 3SL was used as substrate, typical cooperative kinetics were found (S 50 =0.15μM, Vmax=154.3nmolmin -1 mg -1 ). The influenza inhibitor zanamivir inhibited the PorPV neuraminidase with IC 50 of 0.24μM. PorPV neuraminidase was activated by Ca 2+ and inhibited by nucleoside triphosphates with the level of inhibition depending on phosphorylation level. The present results open possibilities to study the role of neuraminidase in the pathogenicity of PorPV infection and its potential inhibitors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Genetic variations in NADPH-CYP450 oxidoreductase in a Czech Slavic cohort

PubMed Central

Tomková, Mária; Panda, Satya Prakash; Šeda, Ondřej; Baxová, Alice; Hůlková, Martina; Masters, Bettie Sue Siler; Martásek, Pavel

2015-01-01

Background Gene polymorphisms encoding the enzyme NADPH–cytochrome P450 oxidoreductase (POR) contribute to inter-individual differences in drug response. Aim To estimate polymorphic allele frequencies of the POR gene in a Czech Slavic population. Materials & Methods The gene POR was analyzed in 322 Czech Slavic individuals from a control cohort by sequencing and HRM analysis. Results Twenty-five SNP genetic variations were identified. Of these variants, 7 were new, unreported SNPs, including two SNPs in the 5´flanking region (g.4965 C>T and g.4994 G>T), one intronic variant (c.1899 −20C>T), one synonymous SNP (p.20Ala=) and three nonsynonymous SNPs (p.Thr29Ser, p.Pro384Leu and p.Thr529Met). The p.Pro384Leu variant exhibited reduced enzymatic activities compared to wild type. Conclusion New POR variant identification indicates that the number of uncommon variants might be specific for each subpopulation being investigated, particularly germane to the singular role that POR plays in providing reducing equivalents to all CYPs in the endoplasmic reticulum. PMID:25712184

Completing the surrogate motherhood process: parental order reporters' attitudes towards surrogacy arrangements, role ambiguity and role conflict.

PubMed

Purewal, Satvinder; Crawshaw, Marilyn; van den Akker, Olga

2012-06-01

This study investigated the attitudes of parental order reporters (PORs) towards their work with surrogacy arrangements and their experiences of role conflict and role ambiguity. A questionnaire was used to assess PORs' perceptions of their role in parental order [PO] applications, attitudes towards surrogacy arrangements and the legal process and the influence of role ambiguity or conflict. Questionnaires were distributed to all PORs employed by the Children and Family Court Advisory and Support Service in England. Thirty-three PORs participated (response rate 46%) who, on average, had each completed five PO applications (range 1-40). Positive attitudes towards surrogacy and the child's needs for openness about origins were found. Concerns about the inadequacy of preparation and assessment arrangements, overseas arrangements and non-regulation of surrogacy agencies were evident. PORs with high-role ambiguity were more likely to report less positive attitudes towards the emotional consequence of surrogacy on offspring. High scores on role ambiguity and role conflict were reflected in less positive attitudes towards the parties' preparation towards parenthood. These results have implications for training, policy and practice in this area.

Monóxido de carbono

EPA Pesticide Factsheets

La mayoria de los accidentes causados por envenenamiento por monoxido de carbono (CO) se producen en los hogares y estan relacionados a nuestras actividades diarias como cocinar y usar la calefaccion.

Disconnection of the Perirhinal and Postrhinal Cortices Impairs Recognition of Objects in Context But Not Contextual Fear Conditioning

PubMed Central

2017-01-01

The perirhinal cortex (PER) is known to process object information, whereas the rodent postrhinal cortex (POR), homolog to the parahippocampal cortex in primates, is thought to process spatial information. A number of studies, however, provide evidence that both areas are involved in processing contextual information. In this study, we tested the hypothesis that the rat POR relies on object information received from the PER to form complex representations of context. Using three fear-conditioning (FC) paradigms (signaled, unsignaled, and renewal) and two context-guided object recognition tasks (with 3D and 2D objects), we examined the effects of crossed excitotoxic lesions to the POR and the contralateral PER. Performance of rats with crossed lesions was compared with that of rats with ipsilateral POR plus PER lesions and sham-operated rats. We found that rats with contralateral PER–POR lesions were impaired in object–context recognition but not in contextual FC. Therefore, interaction between the POR and PER is necessary for context-guided exploratory behavior but not for associating fear with context. Our results provide evidence for the hypothesis that the POR relies on object and pattern information from the PER to encode representations of context. The association of fear with a context, however, may be supported by alternate cortical and/or subcortical pathways when PER–POR interaction is not available. Our results suggest that contextual FC may represent a special case of context-guided behavior. SIGNIFICANCE STATEMENT Representations of context are important for perception, memory, decision making, and other cognitive processes. Moreover, there is extensive evidence that the use of contextual representations to guide appropriate behavior is disrupted in neuropsychiatric and neurological disorders including developmental disorders, schizophrenia, affective disorders, and Alzheimer's disease. Many of these disorders are accompanied by changes in parahippocampal and hippocampal structures. Understanding how context is represented in the brain and how parahippocampal structures are involved will enhance our understanding and treatment of the cognitive and behavioral symptoms associated with neurological disorders and neuropsychiatric disease. PMID:28411272

Paleoenvironmental implications of taxonomic variation among δ 15 N values of chloropigments

NASA Astrophysics Data System (ADS)

Higgins, Meytal B.; Wolfe-Simon, Felisa; Robinson, Rebecca S.; Qin, Yelun; Saito, Mak A.; Pearson, Ann

2011-11-01

Natural variations in the ratios of nitrogen isotopes in biomass reflect variations in nutrient sources utilized for growth. In order to use δ 15N values of chloropigments of photosynthetic organisms to determine the corresponding δ 15N values of biomass - and by extension, surface waters - the isotopic offset between chlorophyll and biomass must be constrained. Here we examine this offset in various geologically-relevant taxa, grown using nutrient sources that may approximate ocean conditions at different times in Earth's history. Phytoplankton in this study include cyanobacteria (diazotrophic and non-diazotrophic), eukaryotic algae (red and green), and anoxygenic photosynthetic bacteria (Proteobacteria), as well as environmental samples from sulfidic lake water. Cultures were grown using N 2, NO 3-, and NH 4+ as nitrogen sources, and were examined under different light regimes and growth conditions. We find surprisingly high variability in the isotopic difference (δ 15N biomass - δ 15N chloropigment) for prokaryotes, with average values for species ranging from -12.2‰ to +11.7‰. We define this difference as ɛpor, a term that encompasses diagenetic porphyrins and chlorins, as well as chlorophyll. Negative values of ɛpor reflect chloropigments that are 15N-enriched relative to biomass. Notably, this enrichment appears to occur only in cyanobacteria. The average value of ɛpor for freshwater cyanobacterial species is -9.8 ± 1.8‰, while for marine cyanobacteria it is -0.9 ± 1.3‰. These isotopic effects group environmentally but not phylogenetically, e.g., ɛpor values for freshwater Chroococcales resemble those of freshwater Nostocales but differ from those of marine Chroococcales. Our measured values of ɛpor for eukaryotic algae (range = 4.7-8.7‰) are similar to previous reports for pure cultures. For all taxa studied, values of ɛpor do not depend on the type of nitrogen substrate used for growth. The observed environmental control of ɛpor suggests that values of ɛpor could be useful for determining the fractional burial of eukaryotic vs. cyanobacterial organic matter in the sedimentary record.

Disconnection of the Perirhinal and Postrhinal Cortices Impairs Recognition of Objects in Context But Not Contextual Fear Conditioning.

PubMed

Heimer-McGinn, Victoria R; Poeta, Devon L; Aghi, Krishan; Udawatta, Methma; Burwell, Rebecca D

2017-05-03

The perirhinal cortex (PER) is known to process object information, whereas the rodent postrhinal cortex (POR), homolog to the parahippocampal cortex in primates, is thought to process spatial information. A number of studies, however, provide evidence that both areas are involved in processing contextual information. In this study, we tested the hypothesis that the rat POR relies on object information received from the PER to form complex representations of context. Using three fear-conditioning (FC) paradigms (signaled, unsignaled, and renewal) and two context-guided object recognition tasks (with 3D and 2D objects), we examined the effects of crossed excitotoxic lesions to the POR and the contralateral PER. Performance of rats with crossed lesions was compared with that of rats with ipsilateral POR plus PER lesions and sham-operated rats. We found that rats with contralateral PER-POR lesions were impaired in object-context recognition but not in contextual FC. Therefore, interaction between the POR and PER is necessary for context-guided exploratory behavior but not for associating fear with context. Our results provide evidence for the hypothesis that the POR relies on object and pattern information from the PER to encode representations of context. The association of fear with a context, however, may be supported by alternate cortical and/or subcortical pathways when PER-POR interaction is not available. Our results suggest that contextual FC may represent a special case of context-guided behavior. SIGNIFICANCE STATEMENT Representations of context are important for perception, memory, decision making, and other cognitive processes. Moreover, there is extensive evidence that the use of contextual representations to guide appropriate behavior is disrupted in neuropsychiatric and neurological disorders including developmental disorders, schizophrenia, affective disorders, and Alzheimer's disease. Many of these disorders are accompanied by changes in parahippocampal and hippocampal structures. Understanding how context is represented in the brain and how parahippocampal structures are involved will enhance our understanding and treatment of the cognitive and behavioral symptoms associated with neurological disorders and neuropsychiatric disease. Copyright © 2017 the authors 0270-6474/17/374819-11$15.00/0.

Porous silicon for drug delivery systems

NASA Astrophysics Data System (ADS)

Abramova, E. N.; Khort, A. M.; Yakovenko, A. G.; Kornilova, D. S.; Slipchenko, E. A.; Prokhorov, D. I.; Shvets, V. I.

2018-01-01

The article deals with main principles of the formation of porous silicon (por-Si) to produce containers for drug delivery systems. Most important por-Si characteristics to produce nanocontainers with required parameters are determined.

Nuevos sistemas de frecuencia intermedia para el IAR

NASA Astrophysics Data System (ADS)

Olalde, J. C.; Perilli, D.; Larrarte, J. J.

Se presenta el diagrama en bloques de los nuevos sistemas de Frecuencia Intermedia para los dos radiómetros instalados en el IAR. Entre las características más importantes del sistema podemos mencionar la posibilidad de conectar cualquiera de las dos antenas a los ``backend" disponibles: analizador espectral de alta resolución (META II) de 0,05 Hz, autocorrelador de 1008 canales y contínuo. Se incorporan al sistema nuevos sintetizadores de frecuencia implementados con PLL y la moderna técnica de síntesis digital directa. Por último, el conjunto del sistema es susceptible de ser configurado por las computadoras de adquisición de datos, supervisadas por otra, que entrega el estado de funcionamiento actual y evita la selección de configuraciones incorrectas por parte del usuario.

[Not Available].

PubMed

San Mauro Martin, Ismael; Mendive Dubourdieu, Paula; Paredes Barato, Víctor; Garicano Vilar, Elena

2016-07-19

Introducción: la tradición de la comida picante desempeña un papel muy importante en el gusto por este tipo de comida y su tolerancia. Las preferencias alimentarias muestran influencia genética y ambiental.Objetivos: estudiar la tolerancia y el gusto por el picante de tres poblaciones, y la influencia hereditaria y del ambiente.Métodos:se realizó una encuesta a 522 sujetos, de tres continentes (Asia, Europa y Latinoamérica) en tres idiomas (español, inglés y chino) a través de Internet. Se realizaron preguntas acerca de la tolerancia al picante, el gusto por los alimentos picantes, su uso, la edad de comienzo de consumo, el gusto del padre y de la madre y si ella lo consumía durante el embarazo y/o lactancia.Resultados: existe diferencia entre el gusto por el picante del hijo y el sexo (p < 0,001), la tolerancia (p < 0,001) y, solo en el sexo femenino, el gusto de la madre por el picante (p < 0,001), su consumo durante el embarazo (p < 0,001) y la lactancia (p = 0,005) y el gusto del padre por el picante (p = 0,003). Existe correlación entre el continente de residencia (p = 0,007) y de nacimiento (p = 0,012) y la tolerancia a los alimentos picantes.Conclusión: la influencia de los progenitores, el género y la composición corporal se relacionaron con gustos y tolerancias diferentes.

Factors associated with anemia in refugee children.

PubMed

Hassan, K; Sullivan, K M; Yip, R; Woodruff, B A

1997-11-01

A nutrition survey was performed in 1990 among children 6 through 35 mo of age living in Palestinian refugee camps in Syria, Jordan, the West Bank, Gaza Strip and Lebanon. Overall, 67% [95% confidence interval (CI): 66, 68] were anemic (hemoglobin <110 g/L), ranging from 54% in the West Bank to 75% in Syria. The following factors were significantly associated with anemia in one or more of three age groups (6-11.9, 12-23.9 and 24-35.9 mo) by logistic regression: living in Syria, Lebanon, or Gaza [with prevalence odds ratios (POR) in the range of 1.4-2.6 depending on the age group and area, relative to children living in Jordan]; never having been breast-fed (POR = 1.7); male sex (POR = 1.2); maternal illiteracy (POR = 1.4 relative to those with >/=6 y of education); having a recent (within 2 wk) or current episode of fever or diarrhea; and stunting. Recent or current illness and stunting interacted in two age groups with the general trend of stunted children with recent or current illness having high POR. Early childhood anemia is associated with factors reflecting poor socioeconomic status and recent diarrheal and febrile illnesses in Palestinian refugee camps.

Evaluation of a 3year intervention to increase adoption of safer nursery crop production practices.

PubMed

Chapman, Larry J; Newenhouse, Astrid C; Karsh, Ben-Tzion

2010-01-01

We conducted a 3year intervention to increase awareness and adoption of eight more profitable nursery crop production practices that reduced certain traumatic and musculoskeletal injury hazards. We disseminated information to nursery managers across seven states using information channels they were known to rely on (e.g. trade publications, public events, university Extension, other managers). We evaluated rolling, independent, probability samples (n=1200) with mail questionnaires before the intervention and after each of 3 intervention years. We also evaluated samples (n=250) from a comparison group of New Zealand nursery managers. The intervention was associated with increased awareness of four of the eight practices among US managers after year 3 compared to their baseline: zippers (20 vs. 32%, p

Transmission scenarios of major vector-borne diseases in Colombia, 1990-2016.

PubMed

Padilla, Julio César; Lizarazo, Fredy Eberto; Murillo, Olga Lucía; Mendigaña, Fernando Antonio; Pachón, Edwin; Vera, Mauricio Javier

2017-03-29

Introducción. Las enfermedades transmitidas por vectores representan más de 17 % de todas las enfermedades infecciosas y causan anualmente un millón de defunciones a nivel mundial. En Colombia, la malaria, el dengue, la enfermedad de Chagas y las leishmaniasis son condiciones endemoepidémicas persistentes.Objetivo. Determinar el comportamiento epidemiológico de las enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016.Materiales y métodos. Se hizo un estudio descriptivo del comportamiento epidemiológico de las principales enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016, con la información proveniente de fuentes oficiales secundarias.Resultados. En el periodo estudiado se registraron 5'360.134 casos de enfermedades transmitidas por vectores, de los cuales 54,7 % fueron de malaria y 24,9 % de dengue. Estos casos concentraron el 80 % de la carga acumulada de casos de enfermedades transmitidas por vectores. Las medianas de las tasas de incidencia fueron 1.371 y 188 por 100.00 habitantes para malaria y dengue, respectivamente. Además, los casos de chikungunya fueron 774.831 desde su introducción en el 2014 y, los de Zika, 117.674 desde su aparición en 2015. En las zonas rurales predominaron las enfermedades parasitarias transmitidas por vectores como la malaria, las leishmaniasis y la enfermedad de Chagas. A nivel urbano, predominaron el dengue, el chikungunya y el Zika.Conclusiones. La transmisión en Colombia de estas enfermedades es persistente en las zonas urbanas y en las rurales, y de tipo endemoepidémico en los casos de malaria, dengue, leishmaniasis y enfermedad de Chagas. Dicha transmisión se ha dado de manera focalizada y con patrones variables de intensidad. Asimismo, se mantienen las condiciones que han favorecido la transmisión emergente de nuevas arbovirosis.

PubMed

Escandón-Nagel, Neli

2016-11-29

Introducción: si bien el Trastorno por Atracón es un trastorno de la conducta alimentaria que  no se da exclusivamente en personas obesas, es más común en este grupo que en sujetos con normopeso, sin embargo no todas las personas con malnutrición por exceso presentan Trastorno por Atracón. Objetivo: identificar el conocimiento actual respecto a las diferencias y semejanzas existentes entre personas con malnutrición por exceso con y sin Trastorno por Atracón.Método: para lograr el objetivo anterior, se realizó una revisión de artículos científicos en torno al tema.Resultados: primero se analizó la comorbilidad psicopatológica en obesidad y después se detectaron similitudes y diferencias entre los grupos de interés, tanto en sintomatología general, como así también en sintomatología de la conducta alimentaria. Además, se identificaron algunos aspectos controversiales, en que existe evidencia contradictoria respecto a la comparación intergrupal.Conclusión: de esta revisión se concluye que en el estudio de la obesidad se hace necesario conocer en mayor profundidad las características del subgrupo de pacientes que además presenta Trastorno por Atracón,  ya que estas personas poseen características distintivas cuyo conocimiento permitirá ofrecer tratamientos integrales más adecuados a las necesidades de los pacientes, lo que posibilitará, en consecuencia, diseñar intervenciones más eficaces.

[Not Available].

PubMed

Latorre-Román, Pedro Ángel; Martínez-López, Emilio José; Ruiz-Ariza, Alberto; Izquierdo-Rus, Tomás; Salas-Sánchez, Jesús; García-Pinillos, Felipe

2016-06-30

Objetivo: el objetivo de este estudio es evaluar las propiedades psicométricas del cuestionario de disfrute por el ejercicio físico (PACES) en adolescentes con sobrepeso y obesidad.Métodos: participaron 139 adolescentes con sobrepeso y obesidad: 91 niñas (edad = 13,85 ± 1,92 años; índice de masa corporal [IMC] = 26,83 ± 3,16 kg/m2) y 48 niños (edad = 14,29 ± 1,62 años; IMC = 28,31 ± 3,74 kg/m2). Para analizar el disfrute por la actividad física se empleó el cuestionario Physical Activity Enjoyment Scale (PACES).Resultados: los resultados del análisis factorial exploratorio y confirmatorio han mostrado una estructura de dos factores; a su vez el PACES presenta una consistencia interna muy alta (alfa de Cronbach = 0,908). La fiabilidad test-retest indica una buena concordancia temporal (Spearman rho = 0,815, p < 0,001). Por último, el PACES en adolescentes con sobrepeso y obesidad manifiesta una validez convergente adecuada con la intencionalidad de ser activo (MIFA), la atracción por la actividad física (CAPA), la resistencia cardiorrespiratoria y los pliegues suprailiacoy subescapular.Conclusión: los resultados confirman que el PACES es una medida válida y fiable del disfrute por la actividad física en adolescentes con sobrepeso y obesidad. El disfrute por la actividad física puede ser relevante en la participación de los adolescentes con sobrepeso y obesidad en estas actividades.

Time spent traveling in motor vehicles and its association with overweight and abdominal obesity in Colombian adults who do not own a car.

PubMed

Flórez Pregonero, Alberto; Gómez, Luis Fernando; Parra, Diana C; Cohen, Daniel D; Arango Paternina, Carlos Mario; Lobelo, Felipe

2012-06-01

This study examined associations between time spent traveling in motor vehicles per week (TSTMV) and BMI and abdominal obesity (AO) among Colombian adults residing in urban areas who do not own car. Secondary data analysis of the 2005 National Nutrition Survey of Colombia was conducted. TSTMV was assessed using the long International Physical Activity Questionnaire. Body composition was measured in 7900 adults. Polytomous and binary logistic regressions were conducted, stratified by gender and adjusted for confounders, including physical activity (PA). Forty-two percent of participants were either overweight or obese according to their BMI, and 22.4% had AO. Males in the middle (10 to 149 min) and highest (>150 min) TSTMV tertiles were more likely to be overweight (POR=1.58, 95% CI=1.13-2.21 and POR=1.55, 95% CI=1.12-2.15 respectively, p-trend=0.012), obese (POR=2.39, 95% CI=1.43-3.99 and POR=1.93, 95% CI=1.22-3.08 respectively, p trend=0.019) and to have AO (POR=1.81, 95% CI=1.18-2.78 and POR=1.73, 95% CI=1.18-2.54 respectively, p-trend=0.009). Associations were not significant in females. TSTMV was positively associated with overweight and AO in adult Colombian males even after adjusting for PA. These findings highlight the potential deleterious health effects of sedentary behaviors such as prolonged traveling time, independently of having met PA recommendations. Copyright © 2012 Elsevier Inc. All rights reserved.

Sunburn and sun-protective behaviors among adults with and without previous nonmelanoma skin cancer: a population-based study

PubMed Central

Fischer, Alexander H.; Wang, Timothy S.; Yenokyan, Gayane; Kang, Sewon; Chien, Anna L.

2016-01-01

Background Individuals with previous nonmelanoma skin cancer (NMSC) are at increased risk for subsequent skin cancer, and should therefore limit UV exposure. Objective To determine whether individuals with previous NMSC engage in better sun protection than those with no skin cancer history. Methods We pooled self-reported data (2005 and 2010 National Health Interview Surveys) from US non-Hispanic white adults (758 with and 34,161 without previous NMSC). We calculated adjusted prevalence odds ratios (aPOR) and 95% confidence intervals (95% CI), taking into account the complex survey design. Results Individuals with previous NMSC versus no history of NMSC had higher rates of frequent use of shade (44.3% versus 27.0%; aPOR=1.41; 1.16–1.71), long sleeves (20.5% versus 7.7%; aPOR=1.55; 1.21–1.98), a wide-brimmed hat (26.1% versus 10.5%; aPOR=1.52; 1.24–1.87), and sunscreen (53.7% versus 33.1%; aPOR=2.11; 95% CI=1.73–2.59), but did not have significantly lower odds of recent sunburn (29.7% versus 40.7%; aPOR=0.95; 0.77–1.17). Among subjects with previous NMSC, recent sunburn was inversely associated with age, sun avoidance, and shade but not sunscreen. Limitations Self-reported cross-sectional data and unavailable information quantifying regular sun exposure. Conclusion Physicians should emphasize sunburn prevention when counseling patients with previous NMSC, especially younger adults, focusing on shade and sun avoidance over sunscreen. PMID:27198078

Treatment of human head lice infestations in a single application with a new galenic lotion.

PubMed

Militão de Sousa, F; Vasconcelos, A W; de Nadon, J; Duhot, P-Y

2010-10-01

To evaluate the efficiency and safety of a new galenic meta-emulsion for the treatment of human head lice (Pediculus capitis) in a single application. A controlled clinical study was conducted comparing lice infestation and nit hatching observed before and after a treatment in a single application. Eighty-two of the 87 children included completed the study. An infestation control was performed on 36 and 46 children, 8 and 24 h respectively after application. Five days later, a meticulous hair examination was carried out to check that the lice infestation was completely cured. After a single application of the lotion being tested, an examination of the scalp with a head lice detection comb, as well as an examination of the rinsing water and the towel used for drying after washing, showed that out of the total 1285 lice, there were no live lice. The percentage of nits hatching before treatment was close to 70%. In comparison, after an 8-h treatment (t(+8)), the percentage of nits hatching was 2.1%, with only 0.35% of living nymphs. After a 24-h treatment (t(+24)), 1.9% hatched with 0.38% living nymphs. Nymphs were revealed to be non-viable. After 5 days (t(+120)), no living adult or immature lice were found on the subjects tested. Moreover, observation of tolerance levels to this treatment at days 1, 5 and 12 showed no side effects. The specific galenic lotion completely cured head lice infestation in the population studied in a single application. The lotion, a patented meta-emulsion, has a mechanical action that asphyxiates lice and nits. Considering the advantages of the single application, the possibility of complete concomitant therapeutics for a whole school population within only 1 day and the high level of tolerance to this treatment, this approach seems simple and promising.

Ecological value of macrophyte cover in creating habitat for microalgae (diatoms) and zooplankton (rotifers and crustaceans) in small field and forest water bodies.

PubMed

Celewicz-Gołdyn, Sofia; Kuczyńska-Kippen, Natalia

2017-01-01

Due to their small area and shallow depth ponds are usually treated as a single sampling unit, while various microhabitats offer different environmental conditions. Thus, we tested the effect of different habitat types typically found within small ponds on the microalgae and zooplankton communities. We found that submerged macrophytes have the strongest impact on microalgae and zooplankton communities out of all the analysed habitats. Some epontic diatoms (e.g. Fragilaria dilatata, Cymbella affinis) and littoral-associated zooplankton species (e.g. Simocephalus vetulus, Lecane bulla) were significantly related to elodeids. However, pelagic species (e.g. bosminids) preferred less complex helophytes, which suggests that the most heterogeneous elodeid habitats were not an anti-predator shelter for cladocerans. Selection of different macrophyte types by taxonomically various organisms suggests that it is not only macrophyte cover that is desired for healthy aquatic environment but that a level of habitat mosaic is required to ensure the well-being of aquatic food webs. Species-specific preferences for different types of macrophytes indicate the high ecological value of macrophyte cover in ponds and a potential direction for the management of small water bodies towards maintaining a great variation of aquatic plants. Moreover, the type of surrounding landscape, reflecting human-induced disturbance (28 field ponds) and natural catchment (26 forest ponds), significantly influenced only zooplankton, while diatoms were affected indirectly through the level of conductivity. Nutrient overload (higher content of TRP) and increased conductivity in the field landscape contributed to a rise in microalgae (e.g. Amphora pediculus, Gomphonema parvulum) and zooplankton (e.g. Thermocyclops oithonoides, Eubosmina coregoni) abundance. An awareness of the responses of both components of plankton communities to environmental factors is necessary for maintaining the good state of small water bodies in various types of landscape.

Topical ivermectin 0.5% lotion for treatment of head lice.

PubMed

Deeks, Louise S; Naunton, Mark; Currie, Marian J; Bowden, Francis J

2013-09-01

To investigate the pharmacology, pharmacokinetics, efficacy, adverse effects, and place in therapy of a single application of topical ivermectin 0.5% lotion for head lice treatment. Literature was obtained by searching MEDLINE, PubMed, CINAHL, and Scopus (January 1980 to January 2013). Abstracts were searched for the terms ivermectin AND (head lice or pediculus or pediculosis), topical ivermectin, ivermectin lotion, ivermectin AND (pharmacology OR pharmacokinetics). The New Drug Application filed with the Food and Drug Administration and the product data sheets for ivermectin were obtained. All English-language articles retrieved from the search were evaluated for relevance to the objective. The recommended first-line head lice treatments in the United States are permethrin 1% or pyrethrins, with malathion 0.5% lotion used as a second-line treatment. Significantly more of the 289 head lice-infested participants using topical ivermectin 0.5% lotion were lice-free at day 15 when compared with vehicle control (73.8% vs 17.6%; P < .001) in 2 studies. Although this rate is lower than other third-line treatments (eg, spinosad 0.9% or benzyl alcohol 5%), topical ivermectin 0.5% lotion is well tolerated (pruritus, the most common adverse event, 0.9%) and requires only a single application. Topical ivermectin 0.5% lotion kills head lice by increasing chloride in muscle cells, causing hyperpolarization and paralysis. Only 1 application is required; when the treated eggs hatch, the lice are not viable because they cannot feed as a result of pharyngeal muscle paralysis. Minimal systemic absorption occurs following topical application. Studies have demonstrated that topical ivermectin 0.5% is a safe and efficacious treatment for head lice. Although it has no documented resistance, there is limited clinical experience, it requires a prescription, and it is expensive. Therefore it should be reserved as a third-line treatment for head lice in the United States.

Activity of tea tree oil and nerolidol alone or in combination against Pediculus capitis (head lice) and its eggs.

PubMed

Di Campli, Emanuela; Di Bartolomeo, Soraya; Delli Pizzi, Patricia; Di Giulio, Mara; Grande, Rossella; Nostro, Antonia; Cellini, Luigina

2012-11-01

Head lice infestation is an emerging social problem in undeveloped and developed countries. Because of louse resistance increasing, several long-used insecticidal compounds have lost their efficacy, and alternatives, such as essential oils, have been proposed to treat this parasitic infestation. The present study investigated the efficacy of two natural substances: tea tree (Melaleuca alternifolia) oil and nerolidol (3,7,11-trimethyl-1,6,10-dodecatrien-3-ol) against lice and its eggs. Products were used alone and in combination (ratio 1:1 and 1:2) from 8 % dilution. The in vitro effect of natural substances at different concentrations were evaluated against 69 head lice (adults and nymphs) and 187 louse eggs collected from school children in Chieti-Pescara (Central Italy) over a 6-month period. The lice mortality was evaluated for 24 h by a stereo light microscope. The ovicidal activity was monitored by microscopic inspections for 15 days. Tea tree oil was more effective than nerolidol against head lice with 100 % mortality at 30 min and 1 % concentration. On the contrary, nerolidol expressed a more pronounced ovicidal activity inducing the failure of 50 % of the eggs to hatch at 1 % concentration after 4 days; the same effect was achieved by using a twice concentration of tea tree oil. The association of the two substances both in ratios 1:1 and 1:2 combined efficaciously their insecticidal and ovicidal effect; in particular, the ratio 1:2 (tea tree oil 0.5 % plus nerolidol 1 %) acted producing both the death of all head lice at 30 min and the abortive effect of louse eggs after 5 days. These results offer new potential application of natural compounds and display a promising scenario in the treatment of pediculosis resistant cases. The development of novel pediculicides containing essential oils could be, in fact, an important tool to control the parasitic infestation.

Novel approach for III-N on Si (111) templates fabrication by low-temperature PA MBE using porous Si layer

NASA Astrophysics Data System (ADS)

Zolotukhin, D.; Seredin, P.; Lenshin, A.; Goloshchapov, D.; Mizerov, A.

2017-11-01

We report on successful growth of GaN nanorods by low-temperature plasma-assisted molecular beam epitaxy on a Si(111) substrate with and without preformed thin porous Si layer (por-Si). The deposited GaN initially forms islands which act as a seed for the wires. Porous structure of the por-Si layer helps to control nucleation islands sizes and achieve homogeneous distribution of the nanorods diameters. In addition 850 nm-thick crack-free GaN layer was formed on Si(111) substrate with preformed por-Si layer.

Risk of specific congenital abnormalities in offspring of women with diabetes.

PubMed

Nielsen, G L; Nørgard, B; Puho, E; Rothman, K J; Sørensen, H T; Czeizel, A E

2005-06-01

To assess the extent to which the increased risk of congenital abnormalities seen in women with pre-gestational insulin-treated diabetes mellitus is unspecific or related to the embryology of specific organs. Cases with congenital abnormalities were identified in the population-based Hungarian Congenital Abnormality Registry from 1980 to 1996 with two newborn children without congenital abnormality selected from the National Birth Registry as controls. We adjusted for parity, maternal age, and use of antipsychotic drugs. Among cases we found 63/22,843 babies with maternal diabetes compared with 50/38,151 in the control group [adjusted prevalence odds ratio (POR) 2.1; 95% CI 1.5-3.1]. The association was strongest for the following congenital abnormalities: renal agenesis (POR: 14.8; 95% CI, 3.5-62.1), obstructive congenital abnormalities of the urinary tract (POR: 4.3; 95% CI, 1.3-13.9), cardiovascular congenital abnormalities (POR: 3.4; 95% CI, 2.0-5.7), and multiple congenital abnormalities (POR: 5.0; 95% CI, 2.4-10.2). These data indicate that pre-gestational maternal diabetes is associated with strong teratogenic effects on the kidney, urinary tract, and heart, and strongly associated with multiple congenital abnormalities. We found no material association between diabetes and spinal congenital abnormalities and limb deficiencies.

Mapping the Laminin Receptor Binding Domains of Neisseria meningitidis PorA and Haemophilus influenzae OmpP2

PubMed Central

Mahdavi, Jafar; Oldfield, Neil J.; Wheldon, Lee M.; Wooldridge, Karl G.; Ala'Aldeen, Dlawer A. A.

2012-01-01

Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae are major bacterial agents of meningitis. They each bind the 37/67-kDa laminin receptor (LamR) via the surface protein adhesins: meningococcal PilQ and PorA, H. influenzae OmpP2 and pneumococcal CbpA. We have previously reported that a surface-exposed loop of the R2 domain of CbpA mediates LamR-binding. Here we have identified the LamR-binding regions of PorA and OmpP2. Using truncated recombinant proteins we show that binding is dependent on amino acids 171–240 and 91–99 of PorA and OmpP2, respectively, which are predicted to localize to the fourth and second surface-exposed loops, respectively, of these proteins. Synthetic peptides corresponding to the loops bound LamR and could block LamR-binding to bacterial ligands in a dose dependant manner. Meningococci expressing PorA lacking the apex of loop 4 and H. influenzae expressing OmpP2 lacking the apex of loop 2 showed significantly reduced LamR binding. Since both loops are hyper-variable, our data may suggest a molecular basis for the range of LamR-binding capabilities previously reported among different meningococcal and H. influenzae strains. PMID:23049988

A role for POR1, a Rac1-interacting protein, in ARF6-mediated cytoskeletal rearrangements.

PubMed Central

D'Souza-Schorey, C; Boshans, R L; McDonough, M; Stahl, P D; Van Aelst, L

1997-01-01

The ARF6 GTPase, the least conserved member of the ADP ribosylation factor (ARF) family, associates with the plasma membrane and intracellular endosome vesicles. Mutants of ARF6 defective in GTP binding and hydrolysis have a marked effect on endocytic trafficking and the gross morphology of the peripheral membrane system. Here we report that expression of the GTPase-defective mutant of ARF6, ARF6(Q67L), remodels the actin cytoskeleton by inducing actin polymerization at the cell periphery. This cytoskeletal rearrangement was inhibited by co-expression of ARF6(Q67L) with deletion mutants of POR1, a Rac1-interacting protein involved in membrane ruffling, but not with the dominant-negative mutant of Rac1, Rac1(S17N). A synergistic effect between POR1 and ARF6 for the induction of actin polymerization was detected. Furthermore, we observed that ARF6 interacts directly with POR1 and that this interaction was GTP dependent. These findings indicate that ARF6 and Rac1 function on distinct signaling pathways to mediate cytoskeletal reorganization, and suggest a role for POR1 as an important regulatory element in orchestrating cytoskeletal rearrangements at the cell periphery induced by ARF6 and Rac1. PMID:9312003

Mapping the laminin receptor binding domains of Neisseria meningitidis PorA and Haemophilus influenzae OmpP2.

PubMed

Abouseada, Noha M; Assafi, Mahde Saleh A; Mahdavi, Jafar; Oldfield, Neil J; Wheldon, Lee M; Wooldridge, Karl G; Ala'Aldeen, Dlawer A A

2012-01-01

Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae are major bacterial agents of meningitis. They each bind the 37/67-kDa laminin receptor (LamR) via the surface protein adhesins: meningococcal PilQ and PorA, H. influenzae OmpP2 and pneumococcal CbpA. We have previously reported that a surface-exposed loop of the R2 domain of CbpA mediates LamR-binding. Here we have identified the LamR-binding regions of PorA and OmpP2. Using truncated recombinant proteins we show that binding is dependent on amino acids 171-240 and 91-99 of PorA and OmpP2, respectively, which are predicted to localize to the fourth and second surface-exposed loops, respectively, of these proteins. Synthetic peptides corresponding to the loops bound LamR and could block LamR-binding to bacterial ligands in a dose dependant manner. Meningococci expressing PorA lacking the apex of loop 4 and H. influenzae expressing OmpP2 lacking the apex of loop 2 showed significantly reduced LamR binding. Since both loops are hyper-variable, our data may suggest a molecular basis for the range of LamR-binding capabilities previously reported among different meningococcal and H. influenzae strains.

Association of low dietary intake of fiber and liquids with constipation: evidence from the National Health and Nutrition Examination Survey.

PubMed

Markland, Alayne D; Palsson, Olafur; Goode, Patricia S; Burgio, Kathryn L; Busby-Whitehead, Jan; Whitehead, William E

2013-05-01

Epidemiological studies support an association of self-defined constipation with fiber and physical activity, but not liquid intake. The aims of this study were to assess the prevalence and associations of dietary fiber and liquid intake to constipation. Analyses were based on data from 10,914 adults (≥20 years) from the 2005-2008 cycles of the National Health and Nutrition Examination Surveys. Constipation was defined as hard or lumpy stools (Bristol Stool Scale type 1 or 2) as the "usual or most common stool type." Dietary fiber and liquid intake from total moisture content were obtained from dietary recall. Co-variables included: age, race, education, poverty income ratio, body mass index, self-reported general health status, chronic illnesses, and physical activity. Prevalence estimates and prevalence odds ratios (POR) were analyzed in adjusted multivariable models using appropriate sampling weights. Overall, 9,373 (85.9%) adults (4,787 women and 4,586 men) had complete stool consistency and dietary data. Constipation rates were 10.2% (95% confidence interval (CI): 9.6, 10.9) for women and 4.0% (95% CI: 3.2, 5.0) for men (P<.001). After multivariable adjustment, low liquid consumption remained a predictor of constipation among women (POR: 1.3, 95% CI: 1.0, 1.6) and men (POR: 2.4, 95% CI: 1.5, 3.9); however, dietary fiber was not a predictor. Among women, African-American race/ethnicity (POR: 1.4, 95% CI: 1.0, 1.9), being obese (POR: 0.7, 95% CI: 0.5,0.9), and having a higher education level (POR: 0.8, 95% CI: 0.7, 0.9) were significantly associated with constipation. The findings support clinical recommendations to treat constipation with increased liquid, but not fiber or exercise.

LIL3, a Light-Harvesting Complex Protein, Links Terpenoid and Tetrapyrrole Biosynthesis in Arabidopsis thaliana1[OPEN

PubMed Central

Rothbart, Maxi; Herbst, Josephine; Wittmann, Daniel; Gruhl, Kirsten

2017-01-01

The LIL3 protein of Arabidopsis (Arabidopsis thaliana) belongs to the light-harvesting complex (LHC) protein family, which also includes the light-harvesting chlorophyll-binding proteins of photosystems I and II, the early-light-inducible proteins, PsbS involved in nonphotochemical quenching, and the one-helix proteins and their cyanobacterial homologs designated high-light-inducible proteins. Each member of this family is characterized by one or two LHC transmembrane domains (referred to as the LHC motif) to which potential functions such as chlorophyll binding, protein interaction, and integration of interacting partners into the plastid membranes have been attributed. Initially, LIL3 was shown to interact with geranylgeranyl reductase (CHLP), an enzyme of terpene biosynthesis that supplies the hydrocarbon chain for chlorophyll and tocopherol. Here, we show another function of LIL3 for the stability of protochlorophyllide oxidoreductase (POR). Multiple protein-protein interaction analyses suggest the direct physical interaction of LIL3 with POR but not with chlorophyll synthase. Consistently, LIL3-deficient plants exhibit substantial loss of POR as well as CHLP, which is not due to defective transcription of the POR and CHLP genes but to the posttranslational modification of their protein products. Interestingly, in vitro biochemical analyses provide novel evidence that LIL3 shows high binding affinity to protochlorophyllide, the substrate of POR. Taken together, this study suggests a critical role for LIL3 in the organization of later steps in chlorophyll biosynthesis. We suggest that LIL3 associates with POR and CHLP and thus contributes to the supply of the two metabolites, chlorophyllide and phytyl pyrophosphate, required for the final step in chlorophyll a synthesis. PMID:28432258

LIL3, a Light-Harvesting Complex Protein, Links Terpenoid and Tetrapyrrole Biosynthesis in Arabidopsis thaliana.

PubMed

Hey, Daniel; Rothbart, Maxi; Herbst, Josephine; Wang, Peng; Müller, Jakob; Wittmann, Daniel; Gruhl, Kirsten; Grimm, Bernhard

2017-06-01

The LIL3 protein of Arabidopsis ( Arabidopsis thaliana ) belongs to the light-harvesting complex (LHC) protein family, which also includes the light-harvesting chlorophyll-binding proteins of photosystems I and II, the early-light-inducible proteins, PsbS involved in nonphotochemical quenching, and the one-helix proteins and their cyanobacterial homologs designated high-light-inducible proteins. Each member of this family is characterized by one or two LHC transmembrane domains (referred to as the LHC motif) to which potential functions such as chlorophyll binding, protein interaction, and integration of interacting partners into the plastid membranes have been attributed. Initially, LIL3 was shown to interact with geranylgeranyl reductase (CHLP), an enzyme of terpene biosynthesis that supplies the hydrocarbon chain for chlorophyll and tocopherol. Here, we show another function of LIL3 for the stability of protochlorophyllide oxidoreductase (POR). Multiple protein-protein interaction analyses suggest the direct physical interaction of LIL3 with POR but not with chlorophyll synthase. Consistently, LIL3-deficient plants exhibit substantial loss of POR as well as CHLP, which is not due to defective transcription of the POR and CHLP genes but to the posttranslational modification of their protein products. Interestingly, in vitro biochemical analyses provide novel evidence that LIL3 shows high binding affinity to protochlorophyllide, the substrate of POR. Taken together, this study suggests a critical role for LIL3 in the organization of later steps in chlorophyll biosynthesis. We suggest that LIL3 associates with POR and CHLP and thus contributes to the supply of the two metabolites, chlorophyllide and phytyl pyrophosphate, required for the final step in chlorophyll a synthesis. © 2017 American Society of Plant Biologists. All Rights Reserved.

Differentiation‐associated urothelial cytochrome P450 oxidoreductase predicates the xenobiotic‐metabolizing activity of “luminal” muscle‐invasive bladder cancers

PubMed Central

Arlt, Volker M.; Indra, Radek; Joel, Madeleine; Stiborová, Marie; Eardley, Ian; Ahmad, Niaz; Otto, Wolfgang; Burger, Maximilian; Rubenwolf, Peter; Phillips, David H.; Southgate, Jennifer

2018-01-01

Extra‐hepatic metabolism of xenobiotics by epithelial tissues has evolved as a self‐defence mechanism but has potential to contribute to the local activation of carcinogens. Bladder epithelium (urothelium) is bathed in excreted urinary toxicants and pro‐carcinogens. This study reveals how differentiation affects cytochrome P450 (CYP) activity and the role of NADPH:P450 oxidoreductase (POR). CYP1A1 and CYP1B1 transcripts were inducible in normal human urothelial (NHU) cells maintained in both undifferentiated and functional barrier‐forming differentiated states in vitro. However, ethoxyresorufin O‐deethylation (EROD) activity, the generation of reactive BaP metabolites and BaP‐DNA adducts, were predominantly detected in differentiated NHU cell cultures. This gain‐of‐function was attributable to the expression of POR, an essential electron donor for all CYPs, which was significantly upregulated as part of urothelial differentiation. Immunohistology of muscle‐invasive bladder cancer (MIBC) revealed significant overall suppression of POR expression. Stratification of MIBC biopsies into “luminal” and “basal” groups, based on GATA3 and cytokeratin 5/6 labeling, showed POR over‐expression by a subgroup of the differentiated luminal tumors. In bladder cancer cell lines, CYP1‐activity was undetectable/low in basal PORlo T24 and SCaBER cells and higher in the luminal POR over‐expressing RT4 and RT112 cells than in differentiated NHU cells, indicating that CYP‐function is related to differentiation status in bladder cancers. This study establishes POR as a predictive biomarker of metabolic potential. This has implications in bladder carcinogenesis for the hepatic versus local activation of carcinogens and as a functional predictor of the potential for MIBC to respond to prodrug therapies. PMID:29323757

Does open-air exposure to volatile organic compounds near a plastic recycling factory cause health effects?

PubMed

Yorifuji, Takashi; Noguchi, Miyuki; Tsuda, Toshihide; Suzuki, Etsuji; Takao, Soshi; Kashima, Saori; Yanagisawa, Yukio

2012-01-01

After a plastic reprocessing factory began to operate in August 2004, the residents around the factory in Neyagawa, Osaka, Japan, began to complain of symptoms. Therefore, we conducted an exposure assessment and a population-based epidemiological study in 2006. To assess exposure, volatile organic compounds (VOCs) and total VOCs were measured at two locations in the vicinity of the factory. In the population-based study, a total of 3,950 residents were targeted. A self-administered questionnaire was used to collect information about subjects' mucocutaneous or respiratory symptoms. Using logistic regression models, we compared the prevalence of symptoms in July 2006 by employing the farthest area from the factory as a reference, and prevalence odds ratios (PORs) and their 95% confidence intervals (CIs) were estimated. The concentration of total VOCs was higher in the vicinity of the factory. The prevalence of mucocutaneous and respiratory symptoms was the highest among the residents in the closest area to the factory. Some symptoms were significantly increased among the residents within 500 m of the factory compared with residents of an area 2800 m from the factory: e.g., sore throat (POR=3.2, 95% CI: 1.3-8.0), eye itch (POR=3.0, 95% CI: 1.5-6.0), eye discharge (POR=6.0, 95% CI: 2.3-15.9), eczema (POR=3.0, 95% CI: 1.1-7.9) and sputum (POR=2.4, 95% CI: 1.1-5.1). Despite of the limitations of this study, these results imply a possible association of open-air VOCs with mucocutaneous and respiratory symptoms. Because this kind of plasticre cycling factory only recently came into operation, more attention should be paid to the operation of plastic recycling factories in the environment.

Sunburn and sun-protective behaviors among adults with and without previous nonmelanoma skin cancer (NMSC): A population-based study.

PubMed

Fischer, Alexander H; Wang, Timothy S; Yenokyan, Gayane; Kang, Sewon; Chien, Anna L

2016-08-01

Individuals with previous nonmelanoma skin cancer (NMSC) are at increased risk for subsequent skin cancer, and should therefore limit ultraviolet exposure. We sought to determine whether individuals with previous NMSC engage in better sun protection than those with no skin cancer history. We pooled self-reported data (2005 and 2010 National Health Interview Surveys) from US non-Hispanic white adults (758 with and 34,161 without previous NMSC). We calculated adjusted prevalence odds ratios (aPOR) and 95% confidence intervals (CI), taking into account the complex survey design. Individuals with previous NMSC versus no history of NMSC had higher rates of frequent use of shade (44.3% vs 27.0%; aPOR 1.41; 95% CI 1.16-1.71), long sleeves (20.5% vs 7.7%; aPOR 1.55; 95% CI 1.21-1.98), a wide-brimmed hat (26.1% vs 10.5%; aPOR 1.52; 95% CI 1.24-1.87), and sunscreen (53.7% vs 33.1%; aPOR 2.11; 95% CI 1.73-2.59), but did not have significantly lower odds of recent sunburn (29.7% vs 40.7%; aPOR 0.95; 95% CI 0.77-1.17). Among those with previous NMSC, recent sunburn was inversely associated with age, sun avoidance, and shade but not sunscreen. Self-reported cross-sectional data and unavailable information quantifying regular sun exposure are limitations. Physicians should emphasize sunburn prevention when counseling patients with previous NMSC, especially younger adults, focusing on shade and sun avoidance over sunscreen. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

El nuevo panorama de la Dinámica Galáctica

NASA Astrophysics Data System (ADS)

Pivovaroff, Michael James

En general, la tendencia imperante en Dinámica Galáctica ha sido considerar que los movimientos estelares son básicamente regulares y que el caos no tiene mayor relevancia en los sistemas estelares. Sin embargo, en el último lustro se vienen acumulando pruebas de la importancia del movimiento caótico en ciertos sistemas estelares que existen en la naturaleza. Por una parte, sobre todo el grupo de David Merritt, lo ha mostrado en los casos de galaxias elípticas con concentraciones centrales de materia; por otra parte, en nuestro propio grupo, lo hemos mostrado para el caso de los satélites galácticos. Las consecuencias de estos hallazgos son tanto de tipo técnico, por la necesidad de construir modelos que contengan órbitas caóticas, como astrofísico, por los efectos del caos sobre la estacionariedad y evolución de los sistemas estelares en los que se presenta.

PubMed

Dipierri, José Edgardo; Bronberg, Rubén Adrian

2017-09-08

Debido al incremento de casos de microcefalia por virus Zika en Brasil el Ministerio de Salud de Argentina recomienda incrementar la vigilancia de esta malformación. A fin de profundizar el conocimiento del comportamiento epidemiológico de microcefalia en el país se analiza la mortalidad infantil por microcefalia entre 1998-2012. Los datos proceden de la Dirección de Estadísticas e Información de Salud (DEIS). Se calculó por provincias y regiones la tasa de mortalidad infantil por microcefalia (TMI-M) y se realizó un análisis de agrupamiento a nivel departamental. Las tasas más elevadas se observaron en las regiones y provincias del norte del país. La distribución espacial de la TMI-M guarda relación con las prevalencias de microcefalia en recién nacidos. Esta distribución se relaciona con la mayor pobreza y consanguinidad del norte de la Argentina, factores sinérgicos predisponentes de la ocurrencia de malformaciones congénitas en general y de microcefalia en particular.

Genetic variations in NADPH-CYP450 oxidoreductase in a Czech Slavic cohort.

PubMed

Tomková, Mária; Panda, Satya Prakash; Šeda, Ondřej; Baxová, Alice; Hůlková, Martina; Siler Masters, Bettie Sue; Martásek, Pavel

2015-01-01

Estimating polymorphic allele frequencies of the NADPH-CYP450 oxidoreductase (POR) gene in a Czech Slavic population. The POR gene was analyzed in 322 individuals from a control cohort by sequencing and high resolution melting analysis. We identified seven unreported SNP genetic variations, including two SNPs in the 5' flanking region (g.4965C>T and g.4994G>T), one intronic variant (c.1899-20C>T), one synonymous SNP (p.20Ala=) and three nonsynonymous SNPs (p.Thr29Ser, p.Pro384Leu and p.Thr529Met). The p.Pro384Leu variant exhibited reduced enzymatic activities compared with wild-type. New POR variant identification indicates the number of uncommon variants might be specific for each subpopulation being investigated, particularly germane to the singular role that POR plays in providing reducing equivalents to all CYP450s in the endoplasmic reticulum. Original submitted 15 September 2014; Revision submitted 17 November 2014.

[Not Available].

PubMed

Ortega, Rosa M

2016-07-19

El artículo de San Mauro y cols. profundiza en un tema de interés prioritario como es el estudio de los hábitos de ingesta de fluidos en personas de cuatro países: España, Portugal, México y Uruguay, para analizar si se cumplen (y si se conocen) las pautas de hidratación marcadas como adecuadas por organismos oficiales y, en concreto, por la EFSA. Es indudable la importancia de una correcta hidratación pues mientras que se puede vivir meses, o años, con una alimentación incorrecta, la deshidratación puede llevar a la muerte en un escaso periodo de tiempo. Por otra parte, un aporte ligeramente insuficiente de fluidos perjudica la salud, capacidad funcional y calidad de vida del individuo, por lo que debe ser evitada. Incluso algunos estudios encuentran hábitos y estilo de vida menos saludables en individuos con menor consumo de fluidos y pautas de hidratación más incorrectas.

Tyrosine oxidation in heme oxygenase: examination of long-range proton-coupled electron transfer.

PubMed

Smirnov, Valeriy V; Roth, Justine P

2014-10-01

Heme oxygenase is responsible for the degradation of a histidine-ligated ferric protoporphyrin IX (Por) to biliverdin, CO, and the free ferrous ion. Described here are studies of tyrosyl radical formation reactions that occur after oxidizing Fe(III)(Por) to Fe(IV)=O(Por(·+)) in human heme oxygenase isoform-1 (hHO-1) and the structurally homologous protein from Corynebacterium diphtheriae (cdHO). Site-directed mutagenesis on hHO-1 probes the reduction of Fe(IV)=O(Por(·+)) by tyrosine residues within 11 Å of the prosthetic group. In hHO-1, Y58· is implicated as the most likely site of oxidation, based on the pH and pD dependent kinetics. The absence of solvent deuterium isotope effects in basic solutions of hHO-1 and cdHO contrasts with the behavior of these proteins in the acidic solution, suggesting that long-range proton-coupled electron transfer predominates over electron transfer.

Observational study to calculate addictive risk to opioids: a validation study of a predictive algorithm to evaluate opioid use disorder.

PubMed

Brenton, Ashley; Richeimer, Steven; Sharma, Maneesh; Lee, Chee; Kantorovich, Svetlana; Blanchard, John; Meshkin, Brian

2017-01-01

Opioid abuse in chronic pain patients is a major public health issue, with rapidly increasing addiction rates and deaths from unintentional overdose more than quadrupling since 1999. This study seeks to determine the predictability of aberrant behavior to opioids using a comprehensive scoring algorithm incorporating phenotypic risk factors and neuroscience-associated single-nucleotide polymorphisms (SNPs). The Proove Opioid Risk (POR) algorithm determines the predictability of aberrant behavior to opioids using a comprehensive scoring algorithm incorporating phenotypic risk factors and neuroscience-associated SNPs. In a validation study with 258 subjects with diagnosed opioid use disorder (OUD) and 650 controls who reported using opioids, the POR successfully categorized patients at high and moderate risks of opioid misuse or abuse with 95.7% sensitivity. Regardless of changes in the prevalence of opioid misuse or abuse, the sensitivity of POR remained >95%. The POR correctly stratifies patients into low-, moderate-, and high-risk categories to appropriately identify patients at need for additional guidance, monitoring, or treatment changes.

Racism in digital era: Development and initial validation of the Perceived Online Racism Scale (PORS v1.0).

PubMed

Keum, Brian TaeHyuk; Miller, Matthew J

2017-04-01

The purpose of this study was to develop the Perceived Online Racism Scale (PORS) to assess perceived online racist interpersonal interactions and exposure to online racist content among people of color. Items were developed through a multistage process involving a comprehensive literature review, focus-groups, qualitative data collection, and survey of online racism experiences. Based on a sample of 1,023 racial minority participants, exploratory and confirmatory factor analyses provided support for a 30-item bifactor model accounted by the general factor and the following 3 specific factors: (a) personal experience of racial cyber-aggression, (b) vicarious exposure to racial cyber-aggression, and (c) online-mediated exposure to racist reality. The PORS demonstrated measurement invariance across racial/ethnic groups in our sample. Internal reliability estimates for the total and subscale scores of the PORS were above .88 and the 4-week test-retest reliability was adequate. Limitations and future directions for research are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Postinfectious bronchiolitis obliterans

PubMed

2018-06-01

La bronquiolitis obliterante es una enfermedad pulmonar crónica infrecuente y grave producto de una lesión del tracto respiratorio inferior. En nuestro país, es más frecuente observarla secundaria a una lesión viral grave, en especial, por adenovirus. La bronquiolitis obliterante se caracteriza por la oclusión parcial o total del lumen de los bronquiolos respiratorios y terminales por tejido inflamatorio y fibrosis, que produce la obstrucción crónica de la vía aérea. Este consenso discute el estado actual del conocimiento en las diferentes áreas de la bronquiolitis obliterante secundaria a una lesión infecciosa.

Faecal calprotectin and magnetic resonance imaging in detecting Crohn’s disease endoscopic postoperative recurrence

PubMed Central

Baillet, Pierre; Cadiot, Guillaume; Goutte, Marion; Goutorbe, Felix; Brixi, Hedia; Hoeffel, Christine; Allimant, Christophe; Reymond, Maud; Obritin-Guilhen, Hélène; Magnin, Benoit; Bommelaer, Gilles; Pereira, Bruno; Hordonneau, Constance; Buisson, Anthony

2018-01-01

AIM To assess magnetic resonance imaging (MRI) and faecal calprotectin to detect endoscopic postoperative recurrence in patients with Crohn’s disease (CD). METHODS From two tertiary centers, all patients with CD who underwent ileocolonic resection were consecutively and prospectively included. All the patients underwent MRI and endoscopy within the first year after surgery or after the restoration of intestinal continuity [median = 6 mo (5.0-9.3)]. The stools were collected the day before the colonoscopy to evaluate faecal calprotectin level. Endoscopic postoperative recurrence (POR) was defined as Rutgeerts’ index ≥ i2b. The MRI was analyzed independently by two radiologists blinded from clinical data. RESULTS Apparent diffusion coefficient (ADC) was lower in patients with endoscopic POR compared to those with no recurrence (2.03 ± 0.32 vs 2.27 ± 0.38 × 10-3 mm²/s, P = 0.032). Clermont score (10.4 ± 5.8 vs 7.4 ± 4.5, P = 0.038) and relative contrast enhancement (RCE) (129.4% ± 62.8% vs 76.4% ± 32.6%, P = 0.007) were significantly associated with endoscopic POR contrary to the magnetic resonance index of activity (MaRIA) (7.3 ± 4.5 vs 4.8 ± 3.7; P = 0.15) and MR scoring system (P = 0.056). ADC < 2.35 × 10-3 mm²/s [sensitivity = 0.85, specificity = 0.65, positive predictive value (PPV) = 0.85, negative predictive value (NPV) = 0.65] and RCE > 100% (sensitivity = 0.75, specificity = 0.81, PPV = 0.75, NPV = 0.81) were the best cut-off values to identify endoscopic POR. Clermont score > 6.4 (sensitivity = 0.61, specificity = 0.82, PPV = 0.73, NPV = 0.74), MaRIA > 3.76 (sensitivity = 0.61, specificity = 0.82, PPV = 0.73, NPV = 0.74) and a MR scoring system ≥ MR1 (sensitivity = 0.54, specificity = 0.82, PPV = 0.70, and NPV = 0.70) demonstrated interesting performances to detect endoscopic POR. Faecal calprotectin values were significantly higher in patients with endoscopic POR (114 ± 54.5 μg/g vs 354.8 ± 432.5 μg/g; P = 0.0075). Faecal calprotectin > 100 μg/g demonstrated high performances to detect endoscopic POR (sensitivity = 0.67, specificity = 0.93, PPV = 0.89 and NPV = 0.77). CONCLUSION Faecal calprotectin and MRI are two reliable tools to detect endoscopic POR in patients with CD. PMID:29434453

Determinacion del error sistematico del momentum de muones producidos por interacciones neutrino-nucleon en el detector MINER$$\

DOE Office of Scientific and Technical Information (OSTI.GOV)

Diaz Bautista, Gonzalo A.

El Modelo Estandar describe todas las partculas observadas en el naturaleza hasta el momento as como las caractersticas que gobiernan a las interacciones fundamentales entre ellas. En especial es posible identicar a las interacciones electromagnetica y debil, las cuales bajo determinadas condiciones de temperatura y energa pueden ser descritas a traves de una sola teora que engloba a ambas. A esta teora se le denomina electrodebil y tiene como nalidad caracterizar las propiedades de la interaccion maniesta a partir de la mezcla de las interacciones electromagnetica y debil, la que tambien lleva como nombre interaccion electrodebil. Particularmente, los neutrinos sonmore » de especial interes ya que, por un lado, interactuan por medio de la interaccion debil muy raramente en comparacion con otras partculas y, por el otro, no son acertadamente descritos por el Modelo Estandar. Por medio de observaciones experimentales que demostraban que los neutrinos cambian de sabor al propagarse, fenomeno llamado oscilaciones de neutrinos, se pudo llegar a la conclusion de que la implicancia de este fenomeno da como consecuencia que los neutrinos efectivamente s tienen masa, algo que entra en contradiccion con la descripcion inicial del Modelo Estandar, el cual los describe como partculas sin masa. Es de esta manera que las oscilaciones de neutrinos han sido y siguen siendo en la actualidad objeto de interes en la Fsica de Altas Energas tanto teorica como experimental. A n de poder realizar mediciones precisas de oscilaciones de neutrinos, los experimentos encargados de estas mediciones deben tratar de reducir sus incertidumbres en lo posible. Una de estas proviene de la caracterizacion de las secciones de choque de los neutrinos cuando interactuan con la materia, particularmente los nucleones al interior de los nucleos atomicos. El experimento MINERA esta orientado, entre otras cosas, a hacer una correcta caracterizacion de secciones de choque neutrino-nucleon por medio del estudio de un tipo especco de interaccion denominado corriente cargada, cuyas partculas de estado nal incluye hadrones y, principalmente, muones. La precision en los resultados de secciones de choque esta sujeta a que la energa y el momentum estos muones sean, a su vez, correctamente caracterizados, incluyendo sus incertidumbres sistematicas. El objetivo de este trabajo de tesis es precisamente presentar la metodologa usada para medir las energas de los muones producidos por interacciones de neutrinos y sus correspondientes incertidumbres asociadas a dicha medicion.« less

Faecal calprotectin and magnetic resonance imaging in detecting Crohn's disease endoscopic postoperative recurrence.

PubMed

Baillet, Pierre; Cadiot, Guillaume; Goutte, Marion; Goutorbe, Felix; Brixi, Hedia; Hoeffel, Christine; Allimant, Christophe; Reymond, Maud; Obritin-Guilhen, Hélène; Magnin, Benoit; Bommelaer, Gilles; Pereira, Bruno; Hordonneau, Constance; Buisson, Anthony

2018-02-07

To assess magnetic resonance imaging (MRI) and faecal calprotectin to detect endoscopic postoperative recurrence in patients with Crohn's disease (CD). From two tertiary centers, all patients with CD who underwent ileocolonic resection were consecutively and prospectively included. All the patients underwent MRI and endoscopy within the first year after surgery or after the restoration of intestinal continuity [median = 6 mo (5.0-9.3)]. The stools were collected the day before the colonoscopy to evaluate faecal calprotectin level. Endoscopic postoperative recurrence (POR) was defined as Rutgeerts' index ≥ i2b. The MRI was analyzed independently by two radiologists blinded from clinical data. Apparent diffusion coefficient (ADC) was lower in patients with endoscopic POR compared to those with no recurrence (2.03 ± 0.32 vs 2.27 ± 0.38 × 10 -3 mm²/s, P = 0.032). Clermont score (10.4 ± 5.8 vs 7.4 ± 4.5, P = 0.038) and relative contrast enhancement (RCE) (129.4% ± 62.8% vs 76.4% ± 32.6%, P = 0.007) were significantly associated with endoscopic POR contrary to the magnetic resonance index of activity (MaRIA) (7.3 ± 4.5 vs 4.8 ± 3.7; P = 0.15) and MR scoring system ( P = 0.056). ADC < 2.35 × 10 -3 mm²/s [sensitivity = 0.85, specificity = 0.65, positive predictive value (PPV) = 0.85, negative predictive value (NPV) = 0.65] and RCE > 100% (sensitivity = 0.75, specificity = 0.81, PPV = 0.75, NPV = 0.81) were the best cut-off values to identify endoscopic POR. Clermont score > 6.4 (sensitivity = 0.61, specificity = 0.82, PPV = 0.73, NPV = 0.74), MaRIA > 3.76 (sensitivity = 0.61, specificity = 0.82, PPV = 0.73, NPV = 0.74) and a MR scoring system ≥ MR1 (sensitivity = 0.54, specificity = 0.82, PPV = 0.70, and NPV = 0.70) demonstrated interesting performances to detect endoscopic POR. Faecal calprotectin values were significantly higher in patients with endoscopic POR (114 ± 54.5 μg/g vs 354.8 ± 432.5 μg/g; P = 0.0075). Faecal calprotectin > 100 μg/g demonstrated high performances to detect endoscopic POR (sensitivity = 0.67, specificity = 0.93, PPV = 0.89 and NPV = 0.77). Faecal calprotectin and MRI are two reliable tools to detect endoscopic POR in patients with CD.

Two dimensional self-assembly zinc porphyrins and zinc phthalocyanines heterojunctions with record high power conversion efficiencies.

PubMed

Yu, Junting; Jiang, Zhou; Hao, Yifan; Zhu, Qianhong; Zhao, Mingliang; Jiang, Xue; Zhao, Jijun

2018-05-15

Compared to inorganic solar cells, the power conversion efficiencies (PCEs) of organic solar cells are much lower, but they are compensated by many merits such as lower cost, less weight, and tunable structures, making them prospective for further applications. Porphyrin and phthalocyanine are the two most significant materials for organic solar cells due to their strong light-absorbing properties and semiconductor characteristics. However, there is little research on the 2D heterojunction solar cells based on these two materials, meanwhile the PCEs of them are still low. Here we have self-assembled several 2D Zinc-porphyrins (ZnPors) and performed first-principles simulation to demonstrate their good stability, suitable light harvesting, and high charge carrier mobility. By perfectly matching lattice constants and band levels between those 2D ZnPors and our previous proposed ZnPcs, eleven type-II organic heterojunctions are constructed to further improve their charge separation capability. Those advantages endow 2D ZnPors and ZnPcs appreciable PCEs for solar cell. Among them, the theoretical PCE of 2D ZnPors/ZnPcs heterojunctions achieves as high as 19.84%, which prevails all reported organic solar cells, and even approaches the PCEs of inorganic solar cells. These results indicate that our 2D ZnPors and 2D ZnPcs are good candidate materials for future organic solar cells. © 2018 IOP Publishing Ltd.

The enhanced immune responses induced by Salmonella enteritidis ghosts loaded with Neisseria gonorrhoeae porB against Salmonella in mice.

PubMed

Jiao, Hongmei; Yang, Hui; Zhao, Dan; He, Li; Chen, Jin; Li, Guocai

2016-11-01

Human health has been seriously endangered by highly prevalent salmonellosis and multidrug-resistant Salmonella strains. Current vaccines suffer from variable immune-protective effects, so more effective ones are needed to control Salmonella infection : Bacterial ghosts have been produced by the expression of lysis gene E from bacteriophage PhiX174 and can be filled with considerable exogenous substances such as DNA or drugs as a novel platform. In this study, Salmonella enteritidis (SE) ghosts were developed and loaded with Neisseria gonorrhoeae porin B (porB) to construct a novel inactive vaccine. Our new studies show that SE ghosts loaded with porB displayed increased production of pro-inflammatory cytokines (IL-1β, IL-6, IL-10 and IL-12p70) in bone marrow-derived dendritic cells (BMDCs), and elicited significantly higher specific systemic and mucosal immune responses to Salmonella than SE ghosts alone. In addition, the novel porB-loaded ghosts conferred higher protective effects on virulent Salmonella challenge. For the first time, we demonstrate that N. gonorrhoeae porB, as a novel adjuvant, can increase the immunogenicity of SE ghosts. Our studies suggested that Salmonella enteritidis ghosts loaded with Neisseria gonorrhoeae porin B might be a useful mucosal Salmonella vaccine candidate for practical use in the future. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Two dimensional self-assembly zinc porphyrin and zinc phthalocyanine heterojunctions with record high power conversion efficiencies

NASA Astrophysics Data System (ADS)

Yu, Junting; Jiang, Zhou; Hao, Yifan; Zhu, Qianhong; Zhao, Mingliang; Jiang, Xue; Zhao, Jijun

2018-06-01

Compared to inorganic solar cells, the power conversion efficiencies (PCEs) of organic solar cells are much lower, but they are compensated by many merits such as lower cost, less weight, and tunable structures, making them prospective for further applications. Porphyrin and phthalocyanine are the two most significant materials for organic solar cells due to their strong light-absorbing properties and semiconductor characteristics. However, there is little research on the 2D heterojunction solar cells based on these two materials, meanwhile the PCEs of them are still low. Here we have self-assembled several 2D zinc porphyrins (ZnPors) and performed first-principles simulation to demonstrate their good stability, suitable light harvesting, and high charge carrier mobility. By perfectly matching lattice constants and molecular energy levels between those 2D ZnPors and our previous proposed zinc phthalocyanines (ZnPcs), 11 type-II organic heterojunctions are constructed to further improve their charge separation capability. Those advantages endow 2D ZnPors and ZnPcs appreciable PCEs for solar cells. Among them, the theoretical PCE of 2D ZnPors/ZnPcs heterojunctions achieves as high as 19.84%, which exceeds all reported organic solar cells, and even approaches the PCEs of inorganic solar cells. These results indicate that our 2D ZnPors and 2D ZnPcs are good candidate materials for future organic solar cells.

Sistemas de transporte inteligentes en cruces fronterizos internacionales : un estudio abarcador : facilitando el comercio y mejorando la seguridad en el transporte

DOT National Transportation Integrated Search

2001-04-01

El Programa de Permisosen Fronteras Internacionales (IBC por sus siglas en ingls) fue iniciado bajo la previsin del Acta de Eficiencia de Transporte Terrestre Intermodal (ISTEA por sus siglas en ingls) en 1991. El programa fue concebido origina...

Transcultural adaptation of the Johns Hopkins Fall Risk Assessment Tool.

PubMed

Martinez, Maria Carmen; Iwamoto, Viviane Ernesto; Latorre, Maria do Rosário Dias de Oliveira; Noronha, Adriana Moreira; Oliveira, Ana Paula de Sousa; Cardoso, Carlos Eduardo Alves; Marques, Ifigenia Augusta Braga; Vendramim, Patrícia; Lopes, Paula Cristina; Sant'Ana, Thais Helena Saes de

2016-08-29

to perform the transcultural adaptation and content validity analysis of the Johns Hopkins Fall Risk Assessment Tool to assess both fall risk and fall-related injury risk for hospitalized elderly in Brazil. the transcultural adaptation consisted of translating the scale to Portuguese (Brazil), back-translating it into its language of origin, establishing a consensus version, and having an expert committee verify its transcultural equivalence. Content assessment was conducted by a committee of judges, ending with the calculation of the items and scales' content validity index. Nurses tested the tool. the scale's translated version went through two evaluation rounds by the judges, based on which, the items with unsatisfactory performance were changed. The content validity index for the items was ≥80.0% and the global index 97.1%. The experimental application showed the scale is user-friendly. the scale presents valid content for the assessment of fall risk and risk of fall-related injuries and is easy to use, with the potential to contribute to the proper identification of risks and the establishment of care actions. realizar a adaptação transcultural para uso no Brasil e a avaliação da validade de conteúdo da Johns Hopkins Fall Risk Assessment Tool para avaliação de risco de quedas e de danos por quedas em pacientes adultos hospitalizados. adaptação transcultural consistiu na tradução da escala para a língua portuguesa (Brasil), retrotradução para a língua de origem, versão de consenso e análise da equivalência transcultural por um comitê de especialistas. A avaliação do conteúdo foi realizada por meio de um comitê de juízes, finalizando com o cálculo do índice de validade de conteúdo dos itens e da escala. Foi realizada a aplicação experimental do instrumento por enfermeiros. a versão traduzida da escala passou por duas rodadas de avaliação pelos juízes, a partir das quais os itens com desempenho insatisfatório foram modificados. O índice de validade de conteúdo para itens foi ≥80,0% e o global foi 97,1%. A aplicação experimental mostrou que a escala é de fácil operacionalização. a escala demonstrou conteúdo válido para a avaliação de risco de quedas e de danos por quedas e ser de fácil operacionalização, podendo contribuir para a adequada identificação dos riscos e consequente direcionamento de ações assistenciais. realizar la adaptación transcultural para ser usada en Brasil y confirmar la validez de contenido de la Johns Hopkins Fall Risk Assessment Tool que evalúa riesgo de caídas y de daños por caídas en pacientes adultos mayores. adaptación transcultural que consistió en la traducción de la escala para el idioma portugués (Brasil); retrotraducción para el idioma de origen; y versión de consenso y análisis de la equivalencia transcultural por un comité de especialistas. La evaluación del contenido fue realizada por medio de un comité de jueces, siendo finalizado con el cálculo del índice de validez de contenido de los ítems y de la escala. Fue realizada la aplicación experimental del instrumento por enfermeros. la versión traducida de la escala pasó por dos vueltas de evaluación por los jueces, a partir de las cuales los ítems con desempeño insatisfactorio fueron modificados. El índice de validez de contenido para los ítems fue ≥80,0% y el global fue 97,1%. La aplicación experimental mostró que la escala es de fácil ejecución. la escala demostró tener un contenido válido para la evaluación de riesgo de caídas y de daños por caídas, y de ser de fácil ejecución; esta escala puede contribuir para la adecuada identificación de los riesgos y consecuentemente para la orientación de acciones asistenciales.

Incorporating an approach to aid river and reservoir fisheries in an altered landscape

USGS Publications Warehouse

Brewer, Shannon K.; Shoup, Daniel E.; Dattillo, John

2018-01-01

Reservoir construction for human-use services alters connected riverine flow patterns and influences fish production. We sampled two pelagic fishes from two rivers and two reservoirs and related seasonal and annual hydrology patterns to the recruitment and growth of each species. River and reservoir populations of Freshwater Drum Aplodinotus grunniens reached similar ages (32 and 31, respectively). Likewise, longevity of Gizzard Shad Dorosoma cepedianum between the two systems was also similar (7 and 8 years, respectively). However, both species grew larger in the rivers compared to reservoir residents. Recruitment of Freshwater Drum in reservoirs was negatively related to water retention time (r2=0.59) suggesting moving water through the reservoir was beneficial. Riverine recruitment of Freshwater Drum populations was negatively related to the annual number of flow reversals and positively related to prespawn discharge (r2 = 0.33). Unlike Freshwater Drum, there was no relationship between flow metrics and Gizzard Shad recruitment in reservoirs. However, recruitment of riverine Gizzard Shad was positively related to high flow pulses during the prespawn and spawning seasons (r2 = 0.48). The growth of both species in reservoirs was positively related to the number of days each year that water levels were above the conservation pool. Growth of Freshwater Drum was also negatively related to minimum reservoir summer water levels (r2 = 0.84). Growth of both Freshwater Drum and Gizzard Shad occupying lotic systems was positively related to May (r2 = 0.86) and July discharge (r2 = 0.84), respectively. In general, growth and recruitment of the reservoir populations was more related to annual water patterns, whereas riverine fishes responded more to seasonal flow patterns. Results of this study provide important information on the relationship between hydrology and pelagic fish production in both rivers and reservoirs. This information is useful if agencies are interested in developing holistic river-reservoir water-allocation plans.

Mechanical fatigue resistance of an implantable branched lead system for a distributed set of longitudinal intrafascicular electrodes

NASA Astrophysics Data System (ADS)

Pena, A. E.; Kuntaegowdanahalli, S. S.; Abbas, J. J.; Patrick, J.; Horch, K. W.; Jung, R.

2017-12-01

Objective. A neural interface system has been developed that consists of an implantable stimulator/recorder can with a 15-electrode lead that trifurcates into three bundles of five individual wire longitudinal intrafascicular electrodes. This work evaluated the mechanical fatigue resistance of the branched lead and distributed electrode system under conditions designed to mimic anticipated strain profiles that would be observed after implantation in the human upper arm. Approach. Custom test setups and procedures were developed to apply linear or angular strain at four critical stress riser points on the lead and electrode system. Each test was performed to evaluate fatigue under a high repetition/low amplitude paradigm designed to test the effects of arm movement on the leads during activities such as walking, or under a low repetition/high amplitude paradigm designed to test the effects of more strenuous upper arm activities. The tests were performed on representative samples of the implantable lead system for human use. The specimens were fabricated using procedures equivalent to those that will be used during production of human-use implants. Electrical and visual inspections of all test specimens were performed before and after the testing procedures to assess lead integrity. Main results. Measurements obtained before and after applying repetitive strain indicated that all test specimens retained electrical continuity and that electrical impedance remained well below pre-specified thresholds for detection of breakage. Visual inspection under a microscope at 10×  magnification did not reveal any signs of damage to the wires or silicone sheathing at the stress riser points. Significance. These results demonstrate that the branched lead of this implantable neural interface system has sufficient mechanical fatigue resistance to withstand strain profiles anticipated when the system is implanted in an arm. The novel test setups and paradigms may be useful in testing other lead systems.

Limited Spillover to Humans from West Nile Virus Viremic Birds in Atlanta, Georgia

PubMed Central

Mead, Daniel G.; Kitron, Uriel D.

2013-01-01

Abstract West Nile Virus (WNV) is a mosquito-borne pathogen that impacts the health of its passerine bird hosts as well as incidentally infected humans in the United States. Intensive enzootic activity among the hosts and vectors does not always lead to human outbreaks, as is the situation throughout much of the southeastern United States. In Georgia, substantial yearly evidence of WNV in the mosquito vectors and avian hosts since 2001 has only led to 324 human cases. Although virus has been consistently isolated from mosquitoes trapped in Atlanta, GA, little is known about viral activity among the passerine hosts. A possible reason for the suppression of WNV spillover to humans is that viremic birds are absent from high human-use areas of the city. To test this hypothesis, multiseason, multihabitat, longitudinal WNV surveillance for active WNV viremia was conducted within the avian host community of urban Atlanta by collection of blood samples from wild passerine birds in five urban microhabitats. WNV was isolated from the serum of six blood samples collected from 630 (0.95%) wild passerine birds in Atlanta during 2010–2012, a proportion similar to that found in the Chicago, IL, area in 2005, when over 200 human cases were reported. Most of the viremic birds were Northern Cardinals, suggesting they may be of particular importance to the WNV transmission cycle in Georgia. Results indicated active WNV transmission in all microhabitats of urban Atlanta, except in the old-growth forest patches. The number of viremic birds was highest in Zoo Atlanta, where 3.5% of samples were viremic. Although not significant, these observations may suggest a possible transmission reduction effect of urban old-growth forests and a potential role in WNV amplification for Zoo Atlanta. Overall, spillover to humans remains a rare occurrence in urban Atlanta settings despite active WNV transmission in the avian population. PMID:24107200

The Acquisition of Lexical Meaning in a Study Abroad Context: The Spanish Prepositions "por" and "para."

ERIC Educational Resources Information Center

Lafford, Barbara A.; Ryan, John M.

1995-01-01

Examination of the development of form/function relations of the prepositions "por" and "para" at different levels of proficiency in the interlanguage of study-abroad students in Granada, Spain, revealed "noncanonical" as well as "canonical" uses of these prepositions. The most common noncanonical uses were…

Proyecto Energético Palmdale; Decisión del Permiso Final

EPA Pesticide Factsheets

Proyecto Energético Palmdale: EPA Región 9 por el presente emite aviso de su decisión final, el cumplimiento con la Ley Federal de Aire Limpio, para la construcción de una planta generadora de electricidad de ciclo combinado y alimentada por gas natural

[Visceral leishmaniasis. Pediatric case report].

PubMed

Gomila H, Andrés; Vanzo, Carolina; Garnero, Analía; Peruzzo, Luisina; Badalotti, Mónica

2017-08-01

La leishmaniasis es una enfermedad causada por parásitos obligados intracelulares pertenecientes al género Leishmania y que reconoce tres formas clínicas principales: cutánea, visceral y mucocutánea. Es una patología del grupo de las "enfermedades desatendidas". Es la única enfermedad tropical transmitida a través de vectores que se ha mantenido endémica por décadas en el sur de Europa. La leishmaniasis visceral representa la forma más grave. Se caracteriza por fiebre, pérdida de peso, anemia y hepatoesplenomegalia. Su período de incubación oscila entre 2 semanas y 18 meses. La leishmaniasis se considera una enfermedad reemergente a nivel mundial. Algunos de los factores que favorecen esta situación son los cambios en las condiciones climáticas, migraciones y urbanizaciones deficitarias en saneamiento ambiental. Se presenta el caso de un niño europeo que estaba vacacionando en Córdoba y fue derivado a nuestro Hospital por fiebre y pancitopenia, lo que generó un abordaje multidisciplinario con resolución clínica favorable. Sociedad Argentina de Pediatría.

Long-term follow-up of a female with congenital adrenal hyperplasia due to P450-oxidoreductase deficiency.

PubMed

Bonamichi, Beatriz D S F; Santiago, Stella L M; Bertola, Débora R; Kim, Chong A; Alonso, Nivaldo; Mendonca, Berenice B; Bachega, Tania A S S; Gomes, Larissa G

2016-10-01

P450 oxidoreductase deficiency (PORD) is a variant of congenital adrenal hyperplasia that is caused by POR gene mutations. The POR gene encodes a flavor protein that transfers electrons from nicotinamide adenine dinucleotide phosphate (NADPH) to all microsomal cytochrome P450 type II (including 21-hydroxylase, 17α-hydroxylase 17,20 lyase and aromatase), which is fundamental for their enzymatic activity. POR mutations cause variable impairments in steroidogenic enzyme activities that result in wide phenotypic variability ranging from 46,XX or 46,XY disorders of sexual differentiation, glucocorticoid deficiency, with or without skeletal malformations similar to Antley-Bixler syndrome to asymptomatic newborns diagnosed during neonatal screening test. Little is known about the PORD long-term evolution. We described a 46,XX patient with mild atypical genitalia associated with severe bone malformation, who was diagnosed after 13 years due to sexual infantilism. She developed large ovarian cysts and late onset adrenal insufficiency during follow-up, both of each regressed after hormone replacement therapies. We also described a late surgical approach for the correction of facial hypoplasia in a POR patient.

Observational study to calculate addictive risk to opioids: a validation study of a predictive algorithm to evaluate opioid use disorder

PubMed Central

Brenton, Ashley; Richeimer, Steven; Sharma, Maneesh; Lee, Chee; Kantorovich, Svetlana; Blanchard, John; Meshkin, Brian

2017-01-01

Background Opioid abuse in chronic pain patients is a major public health issue, with rapidly increasing addiction rates and deaths from unintentional overdose more than quadrupling since 1999. Purpose This study seeks to determine the predictability of aberrant behavior to opioids using a comprehensive scoring algorithm incorporating phenotypic risk factors and neuroscience-associated single-nucleotide polymorphisms (SNPs). Patients and methods The Proove Opioid Risk (POR) algorithm determines the predictability of aberrant behavior to opioids using a comprehensive scoring algorithm incorporating phenotypic risk factors and neuroscience-associated SNPs. In a validation study with 258 subjects with diagnosed opioid use disorder (OUD) and 650 controls who reported using opioids, the POR successfully categorized patients at high and moderate risks of opioid misuse or abuse with 95.7% sensitivity. Regardless of changes in the prevalence of opioid misuse or abuse, the sensitivity of POR remained >95%. Conclusion The POR correctly stratifies patients into low-, moderate-, and high-risk categories to appropriately identify patients at need for additional guidance, monitoring, or treatment changes. PMID:28572737

Low oxygen environment facilitates embryo availability for older ovarian responders (PORs).

PubMed

Li, Mingzhao; Li, Zhibin; Shi, Juanzi

2018-04-18

We aimed to investigate the different effects of low oxygen (5% O 2 ) and atmospheric oxygen (20% O 2 ) on in vitro fertilization for older poor ovarian responders (PORs). We selected 1080 older PORs who met two criteria: (i) advanced maternal age (≥40) and (ii) an abnormal ovarian reserve test. All the patients used the ultra-short term protocols with GnRH agonist and recombinant FSH for controlled ovarian hyperstimulation (COH). About 506 cycles were performed in the incubators with 5% O 2 and 574 cycles were performed in the incubators with 20% O 2 . No significant differences were observed in normal fertilization rates (59.68 versus 60.25%; p = .691) and cancelation rates (18.97 versus 19.34%; p = .879) between two groups. The number of available embryos (1.77 ± 0.57 versus 1.52 ± 0.50; p = .041) and mean number of cells on Day 3 (7.49 ± 1.82 versus 7.16 ± 1.70; p = .032) were significantly higher in 5% O 2 group compared to that in 20% O 2 group. It showed no significant differences in the implantation rates (27.43 versus 24.11%; p = .803) and clinical pregnancy rates (36.34 versus 30.05%; p = .307) between two groups. The employ of low oxygen culture did not improve clinical pregnancy rate for older PORs. However, it benefited early embryonic development for older PORs.

Adjuvant Effects Elicited by Novel Oligosaccharide Variants of Detoxified Meningococcal Lipopolysaccharides on Neisseria meningitidis Recombinant PorA Protein: A Comparison in Mice

PubMed Central

Mehta, Ojas H.; Norheim, Gunnstein; Hoe, J . Claire; Rollier, Christine S.; Nagaputra, Jerry C.; Makepeace, Katherine; Saleem, Muhammad; Chan, Hannah; Ferguson, David J. P.; Jones, Claire; Sadarangani, Manish; Hood, Derek W.; Feavers, Ian; Derrick, Jeremy P.; Pollard, Andrew J.; Moxon, E . Richard

2014-01-01

Neisseria meningitidis lipopolysaccharide (LPS) has adjuvant properties that can be exploited to assist vaccine immunogenicity. The modified penta-acylated LPS retains the adjuvant properties of hexa-acylated LPS but has a reduced toxicity profile. In this study we investigated whether two modified glycoform structures (LgtE and IcsB) of detoxified penta-acylated LPS exhibited differential adjuvant properties when formulated as native outer membrane vesicles (nOMVs) as compared to the previously described LgtB variant. Detoxified penta-acylated LPS was obtained by disruption of the lpxL1 gene (LpxL1 LPS), and three different glycoforms were obtained by disruption of the lgtB, lgtE or icsB genes respectively. Mice (mus musculus) were immunized with a recombinant PorA P1.7-2,4 (rPorA) protein co-administered with different nOMVs (containing a different PorA serosubtype P1.7,16), each of which expressed one of the three penta-acylated LPS glycoforms. All nOMVs induced IgG responses against the rPorA, but the nOMVs containing the penta-acylated LgtB-LpxL1 LPS glycoform induced significantly greater bactericidal activity compared to the other nOMVs or when the adjuvant was Alhydrogel. Compared to LgtE or IcsB LPS glycoforms, these data support the use of nOMVs containing detoxified, modified LgtB-LpxL1 LPS as a potential adjuvant for future meningococcal protein vaccines. PMID:25545241

Perception of recovery of households affected by 2008 Wenchuan earthquake: A structural equation model

PubMed Central

Lin, Le; Wang, Ying; Liu, Tianxue

2017-01-01

Much of the literature on recovery focuses on the economy, the physical environment and infrastructure at a macro level, which may ignore the personal experiences of affected individuals during recovery. This paper combines internal factors at a micro level and external factors at a macro level to model for understanding perception of recovery (PoR). This study focuses on areas devastated by the 2008 Wenchuan earthquake in China. With respect to three recovery-related aspects (house recovery condition (HRC), family recovery power (FRP) and reconstruction investment (RI)), structural equation modeling (SEM) was applied. It was found that the three aspects (FRP, HRC and RI) effectively explain how earthquake affected households perceive recovery. Internal factors associated with FRP contributed the most to favourable PoR, followed by external factors associated with HRC. Findings identified that for PoR the importance of active recovery within households outweighed an advantageous house recovery condition. At the same time, households trapped in unfavourable external conditions would invest more in housing recovery, which result in wealth accumulation and improved quality of life leading to a high level of PoR. In addition, schooling in households showed a negative effect on improving PoR. This research contributes to current debates around post-disaster permanent housing policy. It is implied that a one-size-fits-all policy in disaster recovery may not be effective and more specific assistance should be provided to those people in need. PMID:28854217

Prevalencia y tamizaje del Trastorno por Déficit de Atención con Hiperactividad en Costa Rica

PubMed Central

Weiss, Nicholas T.; Schuler, Jovita; Monge, Silvia; McGough, James J.; Chavira, Denise; Bagnarello, Monica; Herrera, Luis Diego; Mathews, Carol A.

2015-01-01

Resumen La investigación tuvo como propósito estimar la prevalencia del Trastorno por Déficit de Atención con Hiperactividad (TDAH) en Costa Rica y determinar si la versión en español del cuestionario Swanson Nolan and Pelham Scale IV (SNAP-IV) es un instrumento de tamizaje útil en una población de niños y niñas escolares costarricenses. El instrumento fue entregado a padres y maestros de 425 niños entre 5 y 13 años de edad (promedio = 8.8). Todos fueron evaluados con el instrumento Swanson, Kotkin, Agler, M-Flynn and Pelham Scale (SKAMP). Su diagnóstico fue confirmado con una entrevista clínica. La sensibilidad y la especificidad del SNAP-IV fueron evaluadas como predictores de criterios de diagnóstico según el DSM-IV. La prevalencia puntual en la muestra del TDAH fue del 5%. El tamizaje más preciso lo hizo el SNAP-IV completado por el maestro en un corte de 20%, con una sensibilidad de 96% y una especificidad de un 82%. La sensibilidad de los instrumentos completados por los padres fue más baja que aquella de los maestros. El SNAP-IV completado por las maestras con un corte aislando el 20% de los mayores puntajes categorizó correctamente a un 87% de los sujetos. PMID:22432094

Encefalitis por anticuerpos contra el receptor de NMDA: experiencia con seis pacientes pediátricos. Potencial eficacia del metotrexato

PubMed Central

Bravo-Oro, Antonio; Abud-Mendoza, Carlos; Quezada-Corona, Arturo; Dalmau, Josep; Campos-Guevara, Verónica

2016-01-01

Introducción La encefalitis por anticuerpos contra el receptor de N-metil-D-aspartato (NMDA) es una entidad cada vez más diagnosticada en edad pediátrica. A diferencia de los adultos, en muchos casos no se asocia a tumores y las manifestaciones iniciales en niños más frecuentes son crisis convulsivas y trastornos del movimiento, mientras que en los adultos predominan las alteraciones psiquiátricas. Casos clínicos Presentamos seis casos pediátricos confirmados con anticuerpos contra la subunidad NR1 del receptor de NMDA en suero y líquido cefalorraquídeo. Cinco de los casos comenzaron con crisis convulsivas como manifestación clínica inicial antes de desarrollar el cuadro clásico de esta entidad. En todos los casos se utilizaron esteroides como primera línea de tratamiento, con los que sólo se observó control de las manifestaciones en uno, por lo que el resto de los pacientes requirió inmunomoduladores de segunda línea. Todos los pacientes recibieron metotrexato como tratamiento inmunomodulador para evitar recaídas y la evolución fue a la mejoría en todos ellos. Conclusiones En nuestra serie de pacientes con encefalitis por anticuerpos contra el receptor de NMDA, ninguno se asoció a tumores. Todos los casos recibieron metotrexato por lo menos durante un año, no observamos eventos adversos clínicos ni por laboratorio, ni hubo secuelas neurológicas ni recaídas durante el tratamiento. Aunque es una serie pequeña y es deseable incrementar el número y tiempo de evolución, consideramos el metotrexato una excelente alternativa como tratamiento inmunomodulador para esta patología. PMID:24150952

Indoor air pollutants and health in the United Arab Emirates.

PubMed

Yeatts, Karin B; El-Sadig, Mohamed; Leith, David; Kalsbeek, William; Al-Maskari, Fatma; Couper, David; Funk, William E; Zoubeidi, Taoufik; Chan, Ronna L; Trent, Chris B; Davidson, Christopher A; Boundy, Maryanne G; Kassab, Maamoon M; Hasan, Mohamed Y; Rusyn, Ivan; Gibson, Jacqueline MacDonald; Olshan, Andrew F

2012-05-01

Comprehensive global data on the health effects of indoor air pollutants are lacking. There are few large population-based multi-air pollutant health assessments. Further, little is known about indoor air health risks in the Middle East, especially in countries undergoing rapid economic development. To provide multifactorial indoor air exposure and health data, we conducted a population-based study of indoor air pollution and health in the United Arab Emirates (UAE). We conducted a cross-sectional study in a population-based sample of 628 households in the UAE. Indoor air pollutants [sulfur dioxide (SO2), nitrogen dioxide (NO2), hydrogen sulfide (H2S), formaldehyde (HCHO), carbon monoxide (CO), and particulate matter] were measured using passive samplers over a 7-day period. Health information was collected from 1,590 household members via in-person interviews. Participants in households with quantified SO2, NO2, and H2S (i.e., with measured concentrations above the limit of quantification) were twice as likely to report doctor-diagnosed asthma. Participants in homes with quantified SO2 were more likely to report wheezing symptoms {ever wheezing, prevalence odds ratio [POR] 1.79 [95% confidence interval (CI) 1.05, 3.05]; speech-limiting wheeze, POR 3.53 (95% CI: 1.06, 11.74)}. NO2 and H2S were similarly associated with wheezing symptoms. Quantified HCHO was associated with neurologic symptoms (difficulty concentrating POR 1.47; 95% CI: 1.02, 2.13). Burning incense daily was associated with increased headaches (POR 1.87; 95% CI: 1.09, 3.21), difficulty concentrating (POR 3.08; 95% CI: 1.70, 5.58), and forgetfulness (POR 2.68: 95% CI: 1.47, 4.89). This study provides new information regarding potential health risks from pollutants commonly found in indoor environments in the UAE and other countries. Multipollutant exposure and health assessments in cohort studies are needed to better characterize health effects of indoor air pollutants.

Association of Low Dietary Intake of Fiber and Liquids with Constipation: Evidence from the National Health and Nutrition Examination Survey (NHANES)

PubMed Central

Markland, Alayne D.; Palsson, Olafur; Goode, Patricia S.; Burgio, Kathryn L.; Busby-Whitehead, Jan; Whitehead, William E.

2013-01-01

Objective Epidemiological studies support an association of self-defined constipation with fiber and physical activity, but not liquid intake. The aims of this study were to assess the prevalence and associations of dietary fiber and liquid intake to constipation. Methods Analyses were based on data from 10,914 adults (≥20 years) from the 2005-2008 cycles of the National Health and Nutrition Examination Surveys (NHANES). Constipation was defined as hard or lumpy stools (Bristol Stool Scale types 1 or 2) as the “usual or most common stool type.” Dietary fiber and liquid intake from total moisture content were obtained from dietary recall. Co-variables included: age, race, education, poverty income ratio, body mass index, self-reported general health status, chronic illnesses, and physical activity. Prevalence estimates and prevalence odds ratios (POR) were analyzed in adjusted multivariable models using appropriate sampling weights. Results Overall, 9,373 (85.9%) adults (4,787 women and 4,586 men) had complete stool consistency and dietary data. Constipation rates were 10.2% (95% CI: 9.6,10.9) for women and 4.0 (95% CI: 3.2,5.0) for men (p<.001). After multivariable adjustment, low liquid consumption remained a predictor of constipation among women (POR: 1.3, 95% CI: 1.0,1.6) and men (POR: 2.4, 95% CI: 1.5,3.9); however, dietary fiber was not a predictor. Among women, African-American race/ethnicity (POR: 1.4, 95% CI: 1.0,1.9), being obese (POR: 0.7, 95% CI: 0.5,0.9), and having a higher education level (POR: 0.8, 95% CI: 0.7,0.9) were significantly associated with constipation. Conclusions The findings support clinical recommendations to treat constipation with increased liquid, but not fiber or exercise. PMID:23567352

Factors associated with the incidence of pressure ulcer during hospital stay.

PubMed

Matozinhos, Fernanda Penido; Velasquez-Melendez, Gustavo; Tiensoli, Sabrina Daros; Moreira, Alexandra Dias; Gomes, Flávia Sampaio Latini

2017-05-25

Estimating the incidence rate of pressure ulcers and verifying factors associated with this occurrence in a cohort of hospitalized patients. This is a cohort study in which the considered outcome was the time until pressure ulcer occurrence. Estimated effect of the variables on the cumulative incidence ratio of the outcome was performed using the Cox proportional hazards model. Variable selection occurred via the Logrank hypothesis test. The sample consisted of 442 adults, with 25 incidents of pressure ulcers. Patients with high scores on the Braden scale presented a higher risk of pressure ulcer incidence when compared to those classified into the low score category. These results reinforce the importance of using the Braden Scale to assist in identifying patients more likely to develop pressure ulcers. Estimar a taxa de incidência de úlcera por pressão e verificar fatores associados a essa ocorrência em uma coorte de pacientes hospitalizados. Trata-se de estudo de coorte no qual o desfecho foi a ocorrência da úlcera por pressão. A estimativa do efeito das variáveis para a proporção de incidência acumulada do desfecho foi realizada utilizando o modelo de riscos proporcionais de Cox. A seleção das variáveis ocorreu por meio do teste de hipóteses Logrank. A amostra foi composta de 442 adultos, com 25 casos incidentes de úlcera por pressão. Pacientes com altos escores na escala de Braden apresentaram maior risco de incidência de úlcera por pressão quando comparados com aqueles classificados na categoria de baixo escore. Os resultados reforçam a importância do uso da Escala de Braden para auxiliar na identificação dos pacientes com maior probabilidade de desenvolver úlcera por pressão.

Missed Opportunities for Human Immunodeficiency Virus and Syphilis Testing Among Men Who Have Sex With Men in China: A Cross-Sectional Study.

PubMed

Ong, Jason J; Fu, Hongyun; Pan, Stephen; Smith, M Kumi; Wu, Dan; Wei, Chongyi; Cao, Bolin; Ma, Wei; Yang, Ligang; Tang, Weiming; Tucker, Joseph D

2018-06-01

Men who have sex with men (MSM) are at high risk of human immunodeficiency virus (HIV)/syphilis. To inform strategies for dual testing, we describe patterns of HIV/syphilis testing, and examine factors associated with never testing for HIV/syphilis in China. An online survey (2016) was completed by MSM from 8 cities: men born biologically male, 16 years or older, and had sex with another man at least once during their lifetime. Demographic, sexual behavioral, and HIV/syphilis testing data were collected. Multivariable multinomial logistic regression identified characteristics associated with men who never tested for HIV/syphilis compared with men who ever tested for both infections. Overall, 2105 men participated. Among them, 35.1% (738/2105) never tested for HIV/syphilis, and in those ever tested for HIV, only half (54.0%, 709/1312) had tested for syphilis. Relative to men who had ever tested for both infections, those with increased probability of never testing for HIV/syphilis include non-gay sexual identity (prevalence odds ratio [POR] 1.86; 95% confidence interval [CI], 1.45-2.37), not disclosed their sexuality/sexual history with men other than their regular partner (POR, 2.22; 95% CI, 1.75-2.78]) or with health professionals (POR, 11.11; 95% CI, 7.69-14.29), no condomless sex with casual partners in the last 3 months (POR, 1.89; 95% CI, 1.37-2.56), no community engagement in sexual health (POR, 15.16; 95% CI, 9.40-24.45), and mainly met partners offline (POR, 1.49; 95% CI, 1.16-1.92). There are significant gaps in lifetime testing for HIV/syphilis among Chinese MSM. Strategies to target never testers and integrate syphilis testing within HIV testing services are urgently needed. Future opportunities include point-of-care dual test kits, and testing in China's expanding primary healthcare system.

Atomic layer deposition of metal oxide by non-aqueous sol-gel chemistry =

NASA Astrophysics Data System (ADS)

Marichy, Catherine

O trabalho apresentado neste manuscrito foi desenvolvido no ambito do programa doutoral intitulado “Deposicao de Camadas Atomicas (ALD) de oxido de metais por sol-gel nao-aquoso”. O objectivo deste trabalho foi a preparacao de hetero-estruturas funcionais por ALD e a sua caracterizacao. Foi desenvolvido um novo processo de deposicao de oxido de estanho a temperatura baixa-moderada, utilizando um metodo ALD nao-aquoso, o qual foi aplicado com sucesso ao revestimento controlado das paredes internas e externas de nanotubos de carbono. Uma vez que a preparacao de nanomateriais funcionais requer uma elevada exatidao do processo de deposicao, foi demonstrada a deposicao precisa de filmes que se adaptem a forma do substrato ou de filmes nano-estruturados constituidos por particulas em varios substratos. Alem disso, foram depositados com grande exatidao varios oxidos de metal em nanotubos de carbono e demonstrou-se a possibilidade de ajustar o revestimento feito por ALD atraves do controlo da funcionalizacao da superficie do substrato nano-estruturado de carbono. As hetero-estruturas obtidas foram posteriormente aplicadas como sensores de gases. O melhoramento verificado na sensibilidade foi atribuido a formacao de heterojuncoes p-n entre o filme de oxido de metais e o suporte. O trabalho desenvolvido tendo como objetivo o controlo do revestimento por ALD atraves da funcionalizacao da superficie do suporte e certamente de interesse para o design de hetero-estruturas funcionais baseadas em substratos de carbono. De facto, durante o ultimo periodo do programa de doutoramento, este conceito foi alargado a funcionalizacao e revestimento com oxidos de metal de fibras de carbono preparadas por “electrospinning”, de forma a melhorar a estabilidade e a atividade eletrocatalitica de catalisadores a base de Pt. Este trabalho foi realizado maioritariamente na Universidade de Aveiro mas tambem na Universidade Nacional de Seul e beneficiou de varias colaboracoes internacionais devido a natureza multidisciplinar da area de investigacao em que esta inserido.

Flavobacterium johnsoniae sprB Is Part of an Operon Spanning the Additional Gliding Motility Genes sprC, sprD, and sprF ▿ †

PubMed Central

Rhodes, Ryan G.; Nelson, Shawn S.; Pochiraju, Soumya; McBride, Mark J.

2011-01-01

Cells of Flavobacterium johnsoniae move rapidly over surfaces by a process known as gliding motility. Gld proteins are thought to comprise the gliding motor that propels cell surface adhesins, such as the 669-kDa SprB. A novel protein secretion apparatus called the Por secretion system (PorSS) is required for assembly of SprB on the cell surface. Genetic and molecular analyses revealed that sprB is part of a seven-gene operon spanning 29.3 kbp of DNA. In addition to sprB, three other genes of this operon (sprC, sprD, and sprF) are involved in gliding. Mutations in sprB, sprC, sprD, and sprF resulted in cells that failed to form spreading colonies on agar but that exhibited some motility on glass in wet mounts. SprF exhibits some similarity to Porphyromonas gingivalis PorP, which is required for secretion of gingipain protease virulence factors via the P. gingivalis PorSS. F. johnsoniae sprF mutants produced SprB protein but were defective in localization of SprB to the cell surface, suggesting a role for SprF in secretion of SprB. The F. johnsoniae PorSS is involved in secretion of extracellular chitinase in addition to its role in secretion of SprB. SprF was not needed for chitinase secretion and may be specifically required for SprB secretion by the PorSS. Cells with nonpolar mutations in sprC or sprD produced and secreted SprB and propelled it rapidly along the cell surface. Multiple paralogs of sprB, sprC, sprD, and sprF are present in the genome, which may explain why mutations in sprB, sprC, sprD, and sprF do not result in complete loss of motility and suggests the possibility that semiredundant SprB-like adhesins may allow movement of cells over different surfaces. PMID:21131497

Indoor Air Pollutants and Health in the United Arab Emirates

PubMed Central

El-Sadig, Mohamed; Leith, David; Kalsbeek, William; Al-Maskari, Fatma; Couper, David; Funk, William E.; Zoubeidi, Taoufik; Chan, Ronna L.; Trent, Chris B.; Davidson, Christopher A.; Boundy, Maryanne G.; Kassab, Maamoon M.; Hasan, Mohamed Y.; Rusyn, Ivan; Gibson, Jacqueline MacDonald; Olshan, Andrew F.

2012-01-01

Background: Comprehensive global data on the health effects of indoor air pollutants are lacking. There are few large population-based multi–air pollutant health assessments. Further, little is known about indoor air health risks in the Middle East, especially in countries undergoing rapid economic development. Objectives: To provide multifactorial indoor air exposure and health data, we conducted a population-based study of indoor air pollution and health in the United Arab Emirates (UAE). Methods: We conducted a cross-sectional study in a population-based sample of 628 households in the UAE. Indoor air pollutants [sulfur dioxide (SO2), nitrogen dioxide (NO2), hydrogen sulfide (H2S), formaldehyde (HCHO), carbon monoxide (CO), and particulate matter] were measured using passive samplers over a 7-day period. Health information was collected from 1,590 household members via in-person interviews. Results: Participants in households with quantified SO2, NO2, and H2S (i.e., with measured concentrations above the limit of quantification) were twice as likely to report doctor-diagnosed asthma. Participants in homes with quantified SO2 were more likely to report wheezing symptoms {ever wheezing, prevalence odds ratio [POR] 1.79 [95% confidence interval (CI) 1.05, 3.05]; speech-limiting wheeze, POR 3.53 (95% CI: 1.06, 11.74)}. NO2 and H2S were similarly associated with wheezing symptoms. Quantified HCHO was associated with neurologic symptoms (difficulty concentrating POR 1.47; 95% CI: 1.02, 2.13). Burning incense daily was associated with increased headaches (POR 1.87; 95% CI: 1.09, 3.21), difficulty concentrating (POR 3.08; 95% CI: 1.70, 5.58), and forgetfulness (POR 2.68: 95% CI: 1.47, 4.89). Conclusions: This study provides new information regarding potential health risks from pollutants commonly found in indoor environments in the UAE and other countries. Multipollutant exposure and health assessments in cohort studies are needed to better characterize health effects of indoor air pollutants. PMID:22357138

Astronomía Gamma desde El Leoncito

NASA Astrophysics Data System (ADS)

Rovero, A. C.; Colombo, E.; Sahade, J.; Weekes, T. C.

La astronomía gamma, en el extremo de energías detectadas hasta el presente, se encuentra en desarrollo en muchas partes del mundo y proporciona resultados sorprendentes a medida que la tecnología avanza en el desarrollo de nuevos detectores. La técnica Cherenkov Atmosférica es la utilizada para la detección, mediante telescopios en tierra, del efecto secundario causado por la radiación gamma de muy altas energías (E ≈ TeV). Por medio de telescopios o arreglos de detectores y utilizando la técnica mencionada, se han podido detectar algunas fuentes puntuales de mucha importancia astrofísica como la Nebulosa del Cangrejo y la galaxia de núcleo activo Markarian 421. El sistema instalado en San Juan, en cooperación con el grupo de Radiación Gamma del Observatorio Whipple, está constituído por tres colectores de 1.5m que registran pulsos de luz generados por las cascadas de partículas producidas por rayos cósmicos de todo tipo al entrar en la atmósfera terrestre. El sistema opera por barrido en ascención recta de la fuente observada que, para esta etapa del experimento, es el Centro Galáctico. Esta fuente extensa es conocida como emisor gamma de energías inferiores al TeV y ha sido observada anteriormente en este rango de energía desde el hemisferio norte pero con elevaciones bajas, situación no óptima para este tipo de técnica. Se presentan los primeros resultados del análisis de los datos obtenidos observando la región del Centro Galáctico, luego de dos años de observaciones, así como una descripción de la técnica Cherenkov Atmosférica y del equipo utilizado en la experiencia.

Heterobimetallic Nitrido Complexes of Group 8 Metalloporphyrins.

PubMed

Cheung, Wai-Man; Chiu, Wai-Hang; de Vere-Tucker, Matthew; Sung, Herman H-Y; Williams, Ian D; Leung, Wa-Hung

2017-05-15

Heterobimetallic nitrido porphyrin complexes with the [(L)(por)M-N-M'(L OEt )Cl 2 ] formula {por 2- = 5,10,15,20-tetraphenylporphyrin (TPP 2- ) or 5,10,15,20-tetra(p-tolyl)porphyrin (TTP 2- ) dianion; L OEt - = [Co(η 5 -C 5 H 5 ){P(O)(OEt) 2 } 3 ] - ; M = Fe, Ru, or Os; M' = Ru or Os; L = H 2 O or pyridine} have been synthesized, and their electrochemistry has been studied. Treatment of trans-[Fe(TPP)(py) 2 ] (py = pyridine) with Ru(VI) nitride [Ru(L OEt )(N)Cl 2 ] (1) afforded Fe/Ru μ-nitrido complex [(py)(TPP)Fe(μ-N)Ru(L OEt )Cl 2 ] (2). Similarly, Fe/Os analogue [(py)(TPP)Fe(μ-N)Os(L OEt )Cl 2 ] (3) was obtained from trans-[Fe(TPP)(py) 2 ] and [Os(L OEt )(N)Cl 2 ]. However, no reaction was found between trans-[Fe(TPP)(py) 2 ] and [Re(L OEt )(N)Cl(PPh 3 )]. Treatment of trans-[M(TPP)(CO)(EtOH)] with 1 afforded μ-nitrido complexes [(H 2 O)(TPP)M(μ-N)Ru(L OEt )Cl 2 ] [M = Ru (4a) or Os (5)]. TTP analogue [(H 2 O)(TTP)Ru(μ-N)Ru(L OEt )Cl 2 ] (4b) was prepared similarly from trans-[Ru(TTP)(CO)(EtOH)] and 1. Reaction of [(H 2 O)(por)M(μ-N)M(L OEt )Cl 2 ] with pyridine gave adducts [(py)(por)M(μ-N)Ru(L OEt )Cl 2 ] [por = TTP, and M = Ru (6); por = TPP, and M = Os (7)]. The diamagnetism and short (por)M-N(nitride) distances in 2 [Fe-N, 1.683(3) Å] and 4b [Ru-N, 1.743(3) Å] are indicative of the M IV ═N═M' IV bonding description. The cyclic voltammograms of the Fe/Ru (2) and Ru/Ru (4b) complexes in CH 2 Cl 2 displayed oxidation couples at approximately +0.29 and +0.35 V versus Fc +/0 (Fc = ferrocene) that are tentatively ascribed to the oxidation of the {L OEt Ru} and {Ru(TTP)} moieties, respectively, whereas the Fe/Os (3) and Os/Ru (5) complexes exhibited Os-centered oxidation at approximately -0.06 and +0.05 V versus Fc +/0 , respectively. The crystal structures of 2 and 4b have been determined.

Hydrocarbon oxidation by beta-halogenated dioxoruthenium(VI) porphyrin complexes: effect of reduction potential (RuVI/V) and C-H bond-dissociation energy on rate constants.

PubMed

Che, Chi-Ming; Zhang, Jun-Long; Zhang, Rui; Huang, Jie-Sheng; Lai, Tat-Shing; Tsui, Wai-Man; Zhou, Xiang-Ge; Zhou, Zhong-Yuan; Zhu, Nianyong; Chang, Chi Kwong

2005-11-18

beta-Halogenated dioxoruthenium(VI) porphyrin complexes [Ru(VI)(F(28)-tpp)O(2)] [F(28)-tpp=2,3,7,8,12,13, 17,18-octafluoro-5,10,15,20-tetrakis(pentafluorophenyl)porphyrinato(2-)] and [Ru(VI)(beta-Br(8)-tmp)O(2)] [beta-Br(8)-tmp=2,3,7,8,12,13,17,18-octabromo-5,10,15,20- tetrakis(2,4,6-trimethylphenyl)porphyrinato(2-)] were prepared from reactions of [Ru(II)(por)(CO)] [por=porphyrinato(2-)] with m-chloroperoxybenzoic acid in CH(2)Cl(2). Reactions of [Ru(VI)(por)O(2)] with excess PPh(3) in CH(2)Cl(2) gave [Ru(II)(F(20)-tpp)(PPh(3))(2)] [F(20)-tpp=5,10,15,20-tetrakis(pentafluorophenyl)porphyrinato(2-)] and [Ru(II)(F(28)-tpp)(PPh(3))(2)]. The structures of [Ru(II)(por)(CO)(H(2)O)] and [Ru(II)(por)(PPh(3))(2)] (por=F(20)-tpp, F(28)-tpp) were determined by X-ray crystallography, revealing the effect of beta-fluorination of the porphyrin ligand on the coordination of axial ligands to ruthenium atom. The X-ray crystal structure of [Ru(VI)(F(20)-tpp)O(2)] shows a Ru=O bond length of 1.718(3) A. Electrochemical reduction of [Ru(VI)(por)O(2)] (Ru(VI) to Ru(V)) is irreversible or quasi-reversible, with the E(p,c)(Ru(VI/V)) spanning -0.31 to -1.15 V versus Cp(2)Fe(+/0). Kinetic studies were performed for the reactions of various [Ru(VI)(por)O(2)], including [Ru(VI)(F(28)-tpp)O(2)] and [Ru(VI)(beta-Br(8)-tmp)O(2)], with para-substituted styrenes p-X-C(6)H(4)CH=CH(2) (X=H, F, Cl, Me, MeO), cis- and trans-beta-methylstyrene, cyclohexene, norbornene, ethylbenzene, cumene, 9,10-dihydroanthracene, xanthene, and fluorene. The second-order rate constants (k(2)) obtained for the hydrocarbon oxidations by [Ru(VI)(F(28)-tpp)O(2)] are up to 28-fold larger than by [Ru(VI)(F(20)-tpp)O(2)]. Dual-parameter Hammett correlation implies that the styrene oxidation by [Ru(VI)(F(28)-tpp)O(2)] should involve rate-limiting generation of a benzylic radical intermediate, and the spin delocalization effect is more important than the polar effect. The k(2) values for the oxidation of styrene and ethylbenzene by [Ru(VI)(por)O(2)] increase with E(p,c)(Ru(VI/V)), and there is a linear correlation between log k(2) and E(p,c)(Ru(VI/V)). The small slope (approximately 2 V(-1)) of the log k(2) versus E(p,c)(Ru(VI/V)) plot suggests that the extent of charge transfer is small in the rate-determining step of the hydrocarbon oxidations. The rate constants correlate well with the C-H bond dissociation energies, in favor of a hydrogen-atom abstraction mechanism.

76 FR 34296 - Proposed Collection; Comment Request for Forms 1040-PR and 1040-SS

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-13

... Form 1040-PR, Planilla para la Declaraci[oacute]n de la Contribuci[oacute]n Federal sobre el Trabajo... Trabajo por Cuenta Propia (Incluyendo el Cr[eacute]dito Tributario Adicional por Hijos para Residentes... Subtitle A, and provide credit to the taxpayer's social security account. Anejo H-PR is used to compute...

76 FR 26241 - Certain Frozen Warmwater Shrimp From Thailand: Notice of Court Decision Not in Harmony With Final...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-06

... Shrimp From Thailand: Notice of Court Decision Not in Harmony With Final Results of Administrative Review... Thailand covering the period of review (POR) of February 1, 2006, through January 31, 2007. DATES... administrative review of certain frozen warmwater shrimp from Thailand covering the POR of February 1, 2006...

Using MOMP typing as an epidemiological tool to investigate outbreaks caused by milkborne Campylobacter jejuni isolates in California

USDA-ARS?s Scientific Manuscript database

We describe using major outer membrane protein (MOMP) typing as a screen to compare the C. jejuni porA gene sequences of clinical outbreak strains from human stool with the porA sequences of dairy farm strains isolated during two milkborne campylobacteriosis outbreak investigations in California. Th...

Mirta Yáñez's Dystopic Vision of Havana

ERIC Educational Resources Information Center

González, Flora M.

2017-01-01

In her 2010 novel "Sangra por la herida," the Cuban novelist, poet, and essayist Mirta Yáñez constructs a panoramic view of metropolitan Havana, following the model of Latin American fiction starting in the 1980s based on a revised version of the detective novel. "Sangra por la herida" functions best as a narrative that…

78 FR 29322 - Silicon Metal From the People's Republic of China: Final Results and Final No Shipments...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-20

... People's Republic of China: Final Results and Final No Shipments Determination of Antidumping Duty... the People's Republic of China (``PRC'').\\1\\ The period of review (``POR'') is June 1, 2011, through... any reviewable transactions during the POR. \\1\\ See Silicon Metal From the People's Republic of China...

77 FR 28570 - Honey From Argentina: Extension of Time Limit for the Final Results of Antidumping Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-15

... DEPARTMENT OF COMMERCE International Trade Administration [A-357-812] Honey From Argentina... administrative review for the 2009-2010 period of review (POR) of honey from Argentina. See Honey From Argentina... producers/exporters of honey from Argentina during the POR.\\1\\ \\1\\ See Preliminary Results for a detailed...

[Professor Frantisek Por MD and Professor Robert Klopstock MD, students at Budapest and Prague Faculties of Medicine].

PubMed

Mydlík, M; Derzsiová, K

2010-11-01

Professor Frantisek Por MD and Professor Robert Klopstock MD were contemporaries, both born in 1899, one in Zvolen, the other in Dombovar, at the time of Austro-Hungarian Monarchy. Prof. Por attended the Faculty of Medicine in Budapest from 1918 to 1920, and Prof. Klopstock studied at the same place between 1917 and 1919. From 1920 until graduation on 6th February 1926, Prof. Por continued his studies at the German Faculty of Medicine, Charles University in Prague. Prof. Klopstock had to interrupt his studies in Budapest due to pulmonary tuberculosis; he received treatment at Tatranske Matliare where he befriended Franz Kafka. Later, upon Kafka's encouragement, he changed institutions and continued his studies at the German Faculty of Medicine, Charles University in Prague, where he graduated the first great go. It is very likely that, during their studies in Budapest and Prague, both professors met repeatedly, even though their life paths later separated. Following his graduation, Prof. Por practiced as an internist in Prague, later in Slovakia, and from 1945 in Kosice. In 1961, he was awarded the title of university professor of internal medicine at the Faculty of Medicine, Pavol Jozef Safarik University in Kosice, where he practiced until his death in 1980. Prof. Klopstock continued his studies in Kiel and Berlin. After his graduation in 1933, he practiced in Berlin as a surgeon and in 1938 left for USA. In 1962, he was awarded the title of university professor of pulmonary surgery in NewYork, where he died in 1972.

77 FR 77017 - Certain Orange Juice From Brazil: Notice of Court Decision Not in Harmony With Final Results of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-31

..., International Trade Administration, Department of Commerce. SUMMARY: On October 24, 2012, the United States... juice (OJ) from Brazil covering the period of review (POR) of March 1, 2008, through February 28, 2009... administrative review of OJ from Brazil covering the POR of March 1, 2008, through February 28, 2009. See Certain...

Unidades generadoras de energía eléctrica para servicios públicos: Revocación del Plan de Energía Limpia: Propuesta

EPA Pesticide Factsheets

La EPA está proponiendo la revocación del Plan de Energía Limpia (CPP, por sus siglas en inglés) – después de completar una revisión minuciosa como fue dictaminada por la Orden Ejecutiva de Independencia Energética.

European Command Hazardous Material Management Program

DTIC Science & Technology

2011-05-12

cause the hazard>; ES: Puede provocar cáncer <indíquese la vía de exposición si se ha demostrado concluyentemente que el peligro no se produce por...demostrado concluyentemente que el peligro no se produce por ninguna otra vía>. H302: Harmful if swallowed; ES: Nocivo en caso de ingestión. H317: May

VERA-CS User Support Activities for PoR 14

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kochunas, Brendan

2017-11-01

The purpose of this milestone is to document the user support activities that took place between 10/1/2016 and 3/31/2017 (PoR 14). In the normal PHI workflow, that also extends to several activities within RTM, a Kanban process is followed. This involves creating tickets for specific work items and track the progress to complete these specific work items.

La EPA ayuda a restaurar el laboratorio de ciencias de Puerto Rico y las capacidades de monitorear la calidad del aire

EPA Pesticide Factsheets

La EPA continúa ayudando a Puerto Rico a responder tras los daños causados por los huracanes Irma y María. La EPA, conforme a una misión asignada por FEMA, y en estrecha cooperación con el gobierno de Puerto Rico, se encuentra apoya

Global Microlending in Education Reform: Enseñá Por Argentina and the Neoliberalization of the Grassroots

ERIC Educational Resources Information Center

Friedrich, Daniel S.

2010-01-01

This article examines the workings and underlying assumptions behind Enseñá por Argentina (Teach for Argentina), one specific program that takes part in the larger and expanding network of Teach for All, by thinking about the ways in which a global push for redefining teaching and teacher education encounters local characteristics and histories,…

78 FR 79665 - Welded Carbon Steel Standard Pipe and Tube Products From Turkey: Final Results of Antidumping...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-31

... Pipe and Tube Products From Turkey: Final Results of Antidumping Duty Administrative Review; 2011-2012... pipe and tube products (welded pipe and tube) from Turkey.\\1\\ The period of review (POR) is May 1, 2011... during the POR.\\2\\ \\1\\ See Welded Carbon Steel Standard Pipe and Tube Products from Turkey: Preliminary...

Clustering of four major lifestyle risk factors among Korean adults with metabolic syndrome.

PubMed

Ha, Shin; Choi, Hui Ran; Lee, Yo Han

2017-01-01

The purpose of this study was to investigate the clustering pattern of four major lifestyle risk factors-smoking, heavy drinking, poor diet, and physical inactivity-among people with metabolic syndrome in South Korea. There were 2,469 adults with metabolic syndrome aged 30 years or older available with the 5th Korean National Health and Nutrition Examination Survey dataset. We calculated the ratio of the observed to expected (O/E) prevalence for the 16 different combinations and the prevalence odds ratios (POR) of four lifestyle risk factors. The four lifestyle risk factors tended to cluster in specific multiple combinations. Smoking and heavy drinking was clustered (POR: 1.86 for male, 4.46 for female), heavy drinking and poor diet were clustered (POR: 1.38 for male, 1.74 for female), and smoking and physical inactivity were also clustered (POR: 1.48 for male). Those who were male, younger, low-educated and living alone were much more likely to have a higher number of lifestyle risk factors. Some helpful implications can be drawn from the knowledge on clustering pattern of lifestyle risk factors for more effective intervention program targeting metabolic syndrome.

Guidelines for Clinical Practice: Hymenoptera sting allergy in children: 2017 update

PubMed

2017-10-01

Las picaduras por himenópteros son frecuentes en la infancia. La mayoría producen reacciones locales, consecuencia de un mecanismo inflamatorio, no alérgico, no tienen progresión y se resuelven con simples medidas terapéuticas. Las reacciones más extensas, generalmente, están asociadas a mecanismos alérgicos, mediados por inmunoglobulina E. Su máxima expresión, la anafilaxia, presenta síntomas cutáneos, respiratorios, cardiovasculares, digestivos y/o neurológicos, con riesgo de muerte. La prevalencia de anafilaxia en pacientes con mastocitosis sistémica es más alta. La familia Hymenoptera, que incluye hormigas coloradas, abejas y avispas, es la causante de las picaduras de mayor riesgo, potencialmente fatales. Los pilares del diagnóstico son la historia clínica, la identificación del insecto, y las pruebas diagnósticas cutáneas y/o in vitro interpretadas por el especialista en Alergia e Inmunología. La inmunoterapia con veneno es el tratamiento de elección para prevenir reacciones anafilácticas por picaduras de himenópteros.

Edades relativas de cúmulos globulares

NASA Astrophysics Data System (ADS)

Miller Bertolami, M.; Forte, J. C.

El trabajo de Rossemberg et al (1999), estudia las edades relativas de cúmulos globulares galácticos mediante el análisis de ciertos parámetros morfológicos de los diagramas color-magnitud de dichos cúmulos. Este trabajo se centra en tres puntos: analizar la consistencia de los resultados obtenidos por Rossemberg et al (1999) al emplear observaciones en el sistema fotométrico de Washington, más precisamente, las magnitudes C y T1 en lugar de las magnitudes V e I utilizadas por dichos autores. De la existencia de colores integrados, metalicidad y edad (relativa) para 21 de los cúmulos utilizados en dicho trabajo, se analiza la consistencia de estos resultados con las dependencias de color integrado como función de la edad y la metalicidad que se desprenden de los modelos teóricos de luz integrada por Worthey (1994), Schulz (2002) y Lee et al (2002). Por último se lleva a cabo una breve comparación de la morfología de los diagramas color-magnitud de los cúmulos globulares y de las isocronas utilizadas, a fin de intentar identificar algunas de las posibles causas de las diferencias observadas en los incisos anteriores.

Crystallization and preliminary crystallographic analysis of selenomethionine-labelled progesterone 5β-reductase from Digitalis lanata Ehrh

DOE Office of Scientific and Technical Information (OSTI.GOV)

Egerer-Sieber, Claudia; Herl, Vanessa; Müller-Uri, Frieder

2006-03-01

Progesterone 5β-reductase is the first stereospecific enzyme in the pathway for the synthesis of cardenolides. To elucidate the structural mechanism of this reaction, we crystallized the selenomethionine-labelled enzyme from D. lanata and report the preliminary analysis of a MAD data set collected from these crystals. Progesterone 5β-reductase (5β-POR) catalyzes the reduction of progesterone to 5β-pregnane-3,20-dione and is the first stereospecific enzyme in the putative biosynthetic pathway of Digitalis cardenolides. Selenomethionine-derivatized 5β-POR from D. lanata was successfully overproduced and crystallized. The crystals belong to space group P4{sub 3}2{sub 1}2, with unit-cell parameters a = 71.73, c = 186.64 Å. A MADmore » data set collected at 2.7 Å resolution allowed the identification of six out of eight possible Se-atom positions. A first inspection of the MAD-phased electron-density map shows that 5β-POR is a Rossmann-type reductase and the quality of the map is such that it is anticipated that a complete atomic model of 5β-POR will readily be built.« less

NADPH: Protochlorophyllide Oxidoreductase-Structure, Catalytic Function, and Role in Prolamellar Body Formation and Morphogenesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Timko, Michael P

2013-02-01

The biosynthesis of chlorophyll is a critical biochemical step in the development of photosynthetic vascular plants and green algae. From photosynthetic bacteria (cyanobacteria) to algae, non-vascular plants, gymnosperms and vascular plants, mechanisms have evolved for protochlorophyllide reduction a key step in chlorophyll synthesis. Protochlorophyllide reduction is carried out by both a light-dependent (POR) and light-independent (LIPOR) mechanisms. NADPH: protochlorophyllide oxidoreductase (EC 1.3.1.33, abbreviated POR) catalyzes the light-dependent reduction of protochlorophyllide (PChlide) to chlorophyllide (Chlide). In contrast, a light-independent protochlorophyllide reductase (LIPOR) involves three plastid gene products (chlL, chlN, and chlB) and several nuclear factors. Our work focused on characterization ofmore » both the POR and LIPOR catalyzed processes.« less

Intraoperative body temperature control: esophageal thermometer versus infrared tympanic thermometer.

PubMed

Poveda, Vanessa de Brito; Nascimento, Ariane de Souza

2016-01-01

To verify the correlation between temperature measurements performed using an infrared tympanic thermometer and an esophageal thermometer during the intraoperative period. A longitudinal study of repeated measures was performed including subjects aged 18 years or older undergoing elective oncologic surgery of the digestive system, with anesthesia duration of at least 1 hour. Temperature measurements were performed simultaneously by a calibrated esophageal thermometer and by a calibrated infrared tympanic thermometer, with laboratory reading precision of ±0.2ºC. The operating room temperature remained between 19 and 21ºC. The study included 51 patients, mostly men (51%), white (80.4%). All patients were kept warm by a forced-air heating system, for an average of 264.14 minutes (SD = 87.7). The two temperature measurements showed no different behavior over time (p = 0.2205), however, tympanic measurements were consistently 1.24°C lower (p<0.0001). The tympanic thermometer presented reliable results but reflected lower temperatures than the esophageal thermometer. Verificar a correlação entre as medidas de temperatura realizadas por meio de um termômetro timpânico por infravermelho e por um termômetro esofágico, durante o período intraoperatório. Realizou-se um estudo longitudinal, de medidas repetidas, incluindo sujeitos com idade igual ou superior a 18 anos, submetidos à cirurgia oncológica eletiva do sistema digestório, com duração da anestesia de, no mínimo, 1 hora. As medidas de temperatura eram realizadas, ao mesmo tempo, por meio de um termômetro esofágico calibrado e por termômetro timpânico por infravermelho calibrado, com precisão de leitura em laboratório de ±0,2ºC. A temperatura da sala operatória permaneceu entre 19 e 21ºC. Foram incluídos 51 pacientes, em sua maioria homens (51%), brancos (80,4%). Todos os pacientes foram aquecidos com o sistema de ar forçado aquecido, em média por 264,14 minutos (DP = 87,7). As duas medidas de temperatura não tiveram comportamento diferente ao longo do tempo (p = 0,2205), mas a medida timpânica foi consistentemente menor em 1,24°C (p < 0,0001). O termômetro timpânico apresentou resultados confiáveis, mas refletiu temperaturas mais baixas do que o termômetro esofágico.

JIATF-SWB: Building an Operational Bridge for the Southwest Border

DTIC Science & Technology

2011-04-12

mexican_cartels_integr.htm. (accessed 20 March 2011). 4 Office of the President. “Obtener la base de datos de Fallecimientos ocurridos por presunta rivalidad...Obtener la base de datos de Fallecimientos ocurridos por presunta rivalidad delincuencial en el periodo diciembre 2006 a diciembre 2010... basing , technical, intelligence, and training support to JIATF-SWB. 15. SUBJECT TERMS Mexico, Southwest Border, USNORTHCOM, Interagency, 16

Increasing Access to Modern Multidisciplinary Breast Cancer Care

DTIC Science & Technology

1999-08-01

Hogan, Ed.M., Georgina De La Torre, B.A., Mary E. Avellone, Ph.D. Northwestern University Medical School Hispanics participate less in breast...Increasing Adherence to Physicians’ Screening Mammography 32-38 Recommendations Project 5: Mujeres Felices por ser Saludables: Happy Healthy Women. A...availability: Results of a controlled clinical trial. Archives of Internal Medicine, 1999; 159:393-398. 38 PROJECT 5 - Mujeres Felices por Ser Saludables

PubMed

Soriguer, Federico

2016-11-29

Desde hace algún tiempo sabemos que la talla de las poblaciones es un buen instrumento para analizar la evolución socioeconómica, habiendo dejado de ser motivo de estudio solo por la biomedicina para serlo también por los economistas y sociólogos. Es lo que han hecho Martínez Carrión y cols., con el trabajo que aparece en este número de Nutrición Hospitalaria.

Adult Student Retention and Achievement with Language-Based Modular Materials. POR FIN: Program Organizing Related Family Instruction in the Neighborhood.

ERIC Educational Resources Information Center

Bexar County School Board, San Antonio, TX.

The goal of the POR FIN research design was to develop a language-based curriculum emphasizing the audiolingual approach and integrating academic and social-functioning subject matter. The modular curriculum is designed so that each lesson is independent and complete in itself, and provides a high degree of motivation, retention, and achievement…

Characterisation by multilocus sequence and porA and flaA typing of Campylobacter jejuni isolated from samples of dog faeces collected in one city in New Zealand.

PubMed

Mohan, V; Stevenson, M A; Marshall, J C; French, N P

2017-07-01

To investigate the prevalence of Campylobacter spp. and C. jejuni in dog faecal material collected from dog walkways in the city of Palmerston North, New Zealand, and to characterise the C. jejuni isolates by multilocus sequence typing (MLST) and porA and flaA antigen gene typing. A total of 355 fresh samples of dogs faeces were collected from bins provided for the disposal of dog faeces in 10 walkways in Palmerston North, New Zealand, between August 2008-July 2009. Presumptive Campylobacter colonies, cultured on modified charcoal cefoperazone deoxycholate plates, were screened for genus Campylobacter and C. jejuni by PCR. The C. jejuni isolates were subsequently characterised by MLST and porA and flaA typing, and C. jejuni sequence types (ST) were assigned. Of the 355 samples collected, 72 (20 (95% CI=16-25)%) were positive for Campylobacter spp. and 22 (6 (95% CI=4-9)%) were positive for C. jejuni. Of the 22 C. jejuni isolates, 19 were fully typed by MLST. Ten isolates were assigned to the clonal complex ST-45 and three to ST-52. The allelic combinations of ST-45/flaA 21/porA 44 (n=3), ST-45/flaA 22/porA 53 (n=3) and ST-52/ flaA 57/porA 905 (n=3) were most frequent. The successful isolation of C. jejuni from canine faecal samples collected from faecal bins provides evidence that Campylobacter spp. may survive outside the host for at least several hours despite requiring fastidious growth conditions in culture. The results show that dogs carry C. jejuni genotypes (ST-45, ST-50, ST-52 and ST-696) that have been reported in human clinical cases. Although these results do not provide any evidence either for the direction of infection or for dogs being a potential risk factor for human campylobacteriosis, dog owners are advised to practice good hygiene with respect to their pets to reduce potential exposure to infection.

Estudio comparativo de las moléculas isovalentes de interés atmosférico CF3Cl y CF3Br y sus correspondientes halógenos aislados Cl y Br.

NASA Astrophysics Data System (ADS)

Mayor, E.; Velasco, A. M.; Martín, I.; Lavín, C.

Los estados Rydberg moleculares han suscitado en los últimos años un creciente interés entre los espectroscopistas experimentales, motivado en parte por el desarrollo de nuevas técnicas espectroscópicas capaces de investigar estos estados altamente excitados electrónicamente. Los procesos de fotoabsorción que implican estados Rydberg en los derivados halogenados del metano son de gran importancia, debido a su abundancia en la atmósfera y a sus implicaciones medioambientales. Por ello, la obtención de datos relativos a sus fuerzas de oscilador es de gran interés. En este trabajo se aborda el estudio de dichas propiedades para las moléculas isovalentes CF3Cl y CF3Br. Ambas moléculas presentan idéntica estructura electrónica para el estado fundamental por lo que se espera que sus espectros Rydberg presenten grandes similitudes, en ausencia de perturbaciones. Por ello y dada la escasez de datos relativos a fuerzas de oscilador, hemos establecido la corrección de nuestros resultados en base a las analogías esperadas en las intensidades espectrales correspondientes a transiciones análogas. Por otro lado, Novak y col. [1] han encontrado experimentalmente un marcado carácter atómico en el espectro correspondiente a estas moléculas, siendo muy similar a los de los átomos de Cl y Br. Por ello en el presente trabajo, además de establecer la comparación entre ambas moléculas hemos buscado las similitudes con sus respectivos halógenos. Los cálculos relativos a las especies moleculares se han realizado utilizando la Metodología Molécular de Orbítales de Defecto Cuántico (MQDO) [2], mientras que para el estudio de los átomos de Cl y Br se empleó la versión relativista del método (RQDO) [3].

Associations between vitamin D levels and polycystic ovary syndrome (PCOS) phenotypes.

PubMed

Davis, Erin M; Peck, Jennifer D; Hansen, Karl R; Neas, Barbara R; Craig, LaTasha B

2018-04-12

Studies comparing serum 25-hydroxyvitamin D concentrations in women with and without PCOS have produced inconsistent results. Additionally, no previous studies have evaluated associations between vitamin D and specific PCOS phenotypes. This case-control study was conducted among women undergoing intrauterine insemination. Cases (n=137) were diagnosed with PCOS and then further classified into 3 diagnostic phenotypes based on combinations of the Rotterdam criteria [ovulatory dysfunction +polycystic ovaries (n=55); ovulatory dysfunction +androgen excess (n=15); and ovulatory dysfunction, +polycystic ovaries, +androgen excess (n=67)]. Controls (n=103) were ovulatory women without PCOS who were undergoing IUI. Serum total 25-hydroxyvitamin D concentrations were categorized as deficient (≤20 ng/ml), insufficient (21-29 ng/ml), and sufficient (≥30 ng/ml). Prevalence odds ratios (PORs) were calculated using logistic regression. A higher proportion (59.9%) of PCOS cases lacked sufficient vitamin D levels compared to controls (47.6%; p-value=0.06). The odds of vitamin D deficiency in all PCOS cases were twice that of controls (POR=2.03, 95% CI 0.97-4.26); however, the association was attenuated after adjusting for body mass index (BMI) and race/ethnicity (adjPOR=1.43,95% CI 0.62, 3.26). When examining PCOS phenotypes exhibiting androgen excess, crude associations were observed for deficient vitamin D levels (unadjPOR=2.93, 95% CI: 1.27, 6.77); however, the association decreased after adjustment for BMI and race/ethnicity (adjPOR=2.03, 95% CI: 0.79, 5.19). Vitamin D deficiency occurred more frequently in PCOS cases with androgen excess, but associations were attenuated after adjusting for BMI and race/ethnicity. Combining etiologically distinct PCOS subgroups may obscure associations with lower vitamin D levels and other potential risk factors.

Self-reported adherence to medical treatment, breastfeeding behaviour, and disease activity during the postpartum period in women with Crohn's disease.

PubMed

Julsgaard, Mette; Nørgaard, Mette; Hvas, Christian Lodberg; Grosen, Anne; Hasseriis, Sara; Christensen, Lisbet Ambrosius

2014-08-01

Adherence to medical treatment among women with Crohn's disease (CD) in the postpartum period has never been examined. The impact of breast-feeding on disease activity remains controversial. We aimed to assess rates of non-adherence to medical treatment among women with CD in the postpartum period. Further, to assess breast-feeding rates and the impact of breast-feeding on the risk of relapse. Within a population of 1.6 million, we identified 154 women with CD who had given birth within a 6-year period. We combined questionnaire data, data from medical records and public register data. We used logistic regression to estimate prevalence odds ratios (POR) for non-adherence, relapse and breast-feeding according to different predictors. Among 105 (80%) respondents, 59 (56%) reported taking medication. Of these, 66.1% reported to be adherent to medical treatment. Fear of medication transmission to the breast milk was stated as the reason for non-adherence in 60%. Those who received counselling regarding medical treatment were less likely to be non-adherent (POR 0.55, 95% confidence interval [CI] 0.1-2.5). In total, 87.6% were breast-feeding. Breast-feeding rates did not vary by medical treatment. Predictors for relapse in CD were smoking (POR 1.85, 95% CI 0.62-5.54) and non-adherence among medical treated (POR 1.25, 95% CI 0.26-6.00). Breast-feeding seemed protective against relapse (POR 0.33, 95% CI 0.10-1.26). Adherence to medical treatment in the postpartum period was high, and counselling seemed to increase adherence. Relapse may be explained by non-adherence or smoking while breast-feeding seemed protective.

TENDENCIA DE LA TUBERCULOSIS EN LA REGIÓN SANITARIA V DE LA PROVINCIA DE BUENOS AIRES, AÑOS 2000–2011

PubMed Central

CHIRICO, CRISTINA; SANJURJO, MYRIAM; IRIBARREN, SARAH; APPENDINO, ANDREA; ZERBINI, ELSA; ETCHEVARRIA, MIRTA

2016-01-01

El objetivo del presente trabajo fue analizar la situación epidemiológica de la tuberculosis (TB) en la Región Sanitaria V (RSV), provincia de Buenos Aires. El estudio de tendencia permitió conocer un valor promedio de las variaciones de la tasa de incidencia (TI), calculadas por regresión lineal simple y expresadas como variación anual promedio (VAP). Se analizaron el número de casos notificados y TI por 100 000 habitantes de todas las formas de TB, los casos de TB pulmonar (TBP) y TBP confirmados por bacteriología, total casos por grupos de edad: 0 – 14; 15 – 29 y mayores de 64 años, entre el 1° de enero de 2000 al 31 de diciembre de 2011. La declinación de la TI fue menor al 5% para todas las formas de TB e inferior en las TBP confirmadas bacteriológicamente. Los casos de TBP y TI más elevadas, se concentraron en el grupo de 15 a 29 años, con tendencia estable o ligeramente ascendente de la TI en la TBP bacilífera. El mismo comportamiento presentaron los casos de TBP infantil con confirmación bacteriológica. La mayor velocidad de descenso en la TI de la TBP se produjo en este grupo de edad, mientras que en mayores de 64 años, el descenso fue sostenido en el tiempo. La TB persiste como un riesgo de salud en la RSV, con casos en edades jóvenes, por lo que sigue siendo necesario fortalecer el control de la TB en esta región. PMID:26117604

Pubertal presentation in seven patients with congenital adrenal hyperplasia due to P450 oxidoreductase deficiency.

PubMed

Idkowiak, Jan; O'Riordan, Stephen; Reisch, Nicole; Malunowicz, Ewa M; Collins, Felicity; Kerstens, Michiel N; Köhler, Birgit; Graul-Neumann, Luitgard Margarete; Szarras-Czapnik, Maria; Dattani, Mehul; Silink, Martin; Shackleton, Cedric H L; Maiter, Dominique; Krone, Nils; Arlt, Wiebke

2011-03-01

P450 oxidoreductase (POR) is a crucial electron donor to all microsomal P450 cytochrome (CYP) enzymes including 17α-hydroxylase (CYP17A1), 21-hydroxylase (CYP21A2) and P450 aromatase. Mutant POR causes congenital adrenal hyperplasia with combined glucocorticoid and sex steroid deficiency. P450 oxidoreductase deficiency (ORD) commonly presents neonatally, with disordered sex development in both sexes, skeletal malformations, and glucocorticoid deficiency. The aim of the study was to describe the clinical and biochemical characteristics of ORD during puberty. Clinical, biochemical, and genetic assessment of seven ORD patients (five females, two males) presenting during puberty was conducted. Predominant findings in females were incomplete pubertal development (four of five) and large ovarian cysts (five of five) prone to spontaneous rupture, in some only resolving after combined treatment with estrogen/progestin, GnRH superagonists, and glucocorticoids. Pubertal development in the two boys was more mildly affected, with some spontaneous progression. Urinary steroid profiling revealed combined CYP17A1 and CYP21A2 deficiencies indicative of ORD in all patients; all but one failed to mount an appropriate cortisol response to ACTH stimulation indicative of adrenal insufficiency. Diagnosis of ORD was confirmed by direct sequencing, demonstrating disease-causing POR mutations. Delayed and disordered puberty can be the first sign leading to a diagnosis of ORD. Appropriate testosterone production during puberty in affected boys but manifest primary hypogonadism in girls with ORD may indicate that testicular steroidogenesis is less dependent on POR than adrenal and ovarian steroidogenesis. Ovarian cysts in pubertal girls may be driven not only by high gonadotropins but possibly also by impaired CYP51A1-mediated production of meiosis-activating sterols due to mutant POR.

Gender Differences in Smoking Among U.S. Working Adults

PubMed Central

Syamlal, Girija; Mazurek, Jacek M.; Dube, Shanta R.

2015-01-01

Background Cigarette smoking remains a leading cause of morbidity and mortality. Although gender differences in cigarette smoking in the U.S. population have been documented, information on these differences among working adults is limited. Purpose To describe the current smoking prevalence by gender among working U.S. adults and examine gender differences in smoking by occupation. Methods The 2004–2011 National Health Interview Survey data for adults aged ≥18 years that were working in the week prior to the interview (N=132,215) were analyzed in 2013. Current cigarette smokers were those who smoked at least 100 cigarettes in their lifetime and currently smoke every day or some days. Results During 2004–2011, an estimated 22.8% of men workers and 18.3% of women workers were current smokers. Of the current smokers, women workers had higher odds of being an everyday smoker (prevalence OR [POR]=1.17, 95% CI=1.09, 1.26); having poor self-rated emotional health (POR=1.28, 95% CI=1.15, 1.41); and having chronic obstructive pulmonary disease (POR=2.45, 95% CI=2.14, 2.80), heart disease (POR=1.27, 95% CI=1.12, 1.45), and current asthma (POR=2.21, 95% CI=1.96, 2.49) compared with men workers. Women in “supervisors, construction, and extraction” (38.9%) occupations and men in “extraction” (40.5%) occupations had the highest smoking prevalence. Conclusion Among working adults, women had lower prevalence of smoking than men, yet women who smoke were more likely than men to have adverse health outcomes, including self-rated poorer physical and emotional health. PMID:25049215

Resonancias en la región trans-neptuniana

NASA Astrophysics Data System (ADS)

Gallardo, T.; Ferraz-Mello, S.

La expansión de la órbita del planeta Neptuno en la etapa de acreción del Sistema Solar exterior (Fernández e Ip 1984, 1996) parece ser un mecanismo eficiente para la captura de planetesimales en las resonancias exteriores con Neptuno (Malhotra 1995). Por otro lado, los estudios dinámicos realizados por varios autores indican que las resonancias son regiones de evolución estable, en contraste con el comportamiento caótico del resto de la región trans-neptuniana. Por estas razones, y si bien los datos observacionales son todavía muy limitados, se supone que los objetos descubiertos se encuentran en alguna de esas resonancias. En esta comunicación presentamos un estudio analítico y numérico de las principales resonancias exteriores con Neptuno.

Buracos negros primordiais e astrofísica observacional

NASA Astrophysics Data System (ADS)

Custódio, P. S.; Horvath, J. E.

2003-02-01

A história da física contemporânea é pródiga em grandes descobertas (a Relatividade e a Mecânica Quântica entre as mais importantes) até meados dos anos '30. O peso destes desenvolvimentos é tão grande que outros feitos de grande porte (por exemplo, a teoria da nucleossíntese nas estrelas) são geralmente considerados como "filhotes" dos primeiros, ao menos na imaginação popular. Porém, algumas exceções à regra não-escrita são dignas de menção. Entre estas últimas está a descoberta por S.W.Hawking e colaboradores das propriedades de emissão dos buracos negros, trabalho que iniciou uma disciplina com vida própria denominada Termodinâmica de Buracos Negros.

UPDATE: MAJOR EARTHQUAKE IN CHILE (II) | CTIO

Science.gov Websites

ciudad de Illapel a mitad de camino entre La Serena y Santiago. Esto fue seguido por un tsunami que en el posterior tsunami. Algunos tienen casas en las partes bajas de La Serena y Coquimbo y tuvieron que evacuar por la noche después de la alerta de tsunami, y algunos han sufrido daños en sus casas o

El proceso hacia la integracion de la equidad por genero al curriculo.(The Process of the Integration of Gender Equity in the Curriculum.)

ERIC Educational Resources Information Center

Rivera-Bermudez, Carmen D.

"El Proyecto Colaborativo de Equidad por Genero en la Educacion," or the Collaborative Project for Gender Equity in Education, was undertaken in Puerto Rico between 1990 and 1992 to study how to facilitate the integration of gender equity themes in the curriculum through the direct action of participating teachers. A study examined the…

Singlet and triplet excitation management in a bichromophoric near-infrared-phosphorescent BODIPY-benzoporphyrin platinum complex

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whited, M. T.; Djurovich, P. I.; Roberts, Sean T.

2011-01-12

Multichromophoric arrays provide one strategy for assembling molecules with intense absorptions across the visible spectrum but are generally focused on systems that efficiently produce and manipulate singlet excitations and therefore are burdened by the restrictions of (a) unidirectional energy transfer and (b) limited tunability of the lowest molecular excited state. In contrast, we present here a multichromophoric array based on four boron dipyrrins (BODIPY) bound to a platinum benzoporphyrin scaffold that exhibits intense panchromatic absorption and efficiently generates triplets. The spectral complementarity of the BODIPY and porphryin units allows the direct observation of fast bidirectional singlet and triplet energy transfermore » processes (k ST( 1BDP→ 1Por) = 7.8 × 10 11 s -1, k TT( 3Por→ 3BDP) = 1.0 × 10 10 s -1, k TT( 3BDP→ 3Por) = 1.6 × 10 10 s -1), leading to a long-lived equilibrated [ 3BDP][Por]⇌[BDP][ 3Por] state. This equilibrated state contains approximately isoenergetic porphyrin and BODIPY triplets and exhibits efficient near-infrared phosphorescence (λ em = 772 nm, Φ = 0.26). Taken together, these studies show that appropriately designed triplet-utilizing arrays may overcome fundamental limitations typically associated with core-shell chromophores by tunable redistribution of energy from the core back onto the antennae.« less

Head louse infestations: epidemiologic survey and treatment evaluation in Argentinian schoolchildren.

PubMed

Chouela, E; Abeldaño, A; Cirigliano, M; Ducard, M; Neglia, V; La Forgia, M; Colombo, A

1997-11-01

Our aim was to demonstrate that the treatment of individual cases is effective, but not sufficient, to control endemic Pediculus capitis, and that eradication of the epidemiologic school focus may lower significantly the prevalence of infestation. Statistical data on the degree of infestation relating to socio-economic and cultural variables were also updated. Therapeutic effects and educational impact were evaluated. An educational and motivational program was designed for pupils, parents, and teachers: 326 children and 15 adults were subjected to clinical and parasitologic evaluation. The recorded parameters included the age, sex, hair style and length, presence of other dermatologic diseases, degree of infestation, clinical remission, parasitologic remission, dwelling type and features, need to share a bed with co-dwellers, availability of home tap water supply, level of family income, and periodic medical controls. The entire population received treatment with neutral shampoo and rinsing cream containing 1% permethrin. Exclusion criteria were the presence of acute scalp inflammation and a history of pyrethrin and/or pyrethroid sensitivity. Statistical analysis was performed as required on data expressed as frequencies, percentages, means, and standard deviations by chi-square and Fisher exact tests. The overall infestation prevalence rate was 81.5%, the highest values corresponding to children from 6 to 11 years of age, with a slight predominance in males (55.4% vs. 44.6%). A significantly greater rate of clinical remission was observed in subjects enjoying home tap water supplies (p < 0.01). The model of research plus action adopted allows the following conclusions to be drawn: (i) individual and isolated treatments for pediculosis are useful, but will not by themselves allow for the epidemiologic control of this parasitosis; (ii) massive, complete, and simultaneous treatments lead to a significant decrease in infestation prevalence; (iii) educational measures tending to foster collective awareness enable greater epidemiologic surveillance to be achieved; (iv) careful inspection of the entire scalp is essential with the use of a powerful light source and lenses with high magnification, as the parasite has no predilection for any given area; (iv) socio-economic and cultural conditions are not relevant for infestation, although a good home tap water supply is essential for treatment.

The impact of asthma in Brazil: a longitudinal analysis of data from a Brazilian national database system.

PubMed

Cardoso, Thiago de Araujo; Roncada, Cristian; Silva, Emerson Rodrigues da; Pinto, Leonardo Araujo; Jones, Marcus Herbert; Stein, Renato Tetelbon; Pitrez, Paulo Márcio

2017-01-01

To present official longitudinal data on the impact of asthma in Brazil between 2008 and 2013. This was a descriptive study of data collected between 2008 and 2013 from an official Brazilian national database, including data on asthma-related number of hospitalizations, mortality, and hospitalization costs. A geographical subanalysis was also performed. In 2013, 2,047 people died from asthma in Brazil (5 deaths/day), with more than 120,000 asthma-related hospitalizations. During the whole study period, the absolute number of asthma-related deaths and of hospitalizations decreased by 10% and 36%, respectively. However, the in-hospital mortality rate increased by approximately 25% in that period. The geographic subanalysis showed that the northern/northeastern and southeastern regions had the highest asthma-related hospitalization and in-hospital mortality rates, respectively. An analysis of the states representative of the regions of Brazil revealed discrepancies between the numbers of asthma-related hospitalizations and asthma-related in-hospital mortality rates. During the study period, the cost of asthma-related hospitalizations to the public health care system was US$ 170 million. Although the numbers of asthma-related deaths and hospital admissions in Brazil have been decreasing since 2009, the absolute numbers are still high, resulting in elevated direct and indirect costs for the society. This shows the relevance of the burden of asthma in middle-income countries. Apresentar dados longitudinais oficiais sobre o impacto da asma no Brasil entre 2008 e 2013. Estudo descritivo de dados extraídos de um banco de dados do governo brasileiro entre 2008 e 2013, no qual foram analisados as hospitalizações e óbitos por asma, bem como o custo das hospitalizações. Foi também realizada uma subanálise geográfica. Em 2013, 2.047 pessoas morreram de asma no Brasil (5 óbitos/dia), com mais de 120.000 hospitalizações por asma. Durante o período de estudo, o número absoluto de óbitos e hospitalizações por asma diminuiu 10% e 36%, respectivamente. No entanto, a taxa de mortalidade hospitalar aumentou aproximadamente 25%. A subanálise geográfica mostrou que as regiões Norte/Nordeste e Sudeste apresentaram as maiores taxas de hospitalização e mortalidade hospitalar por asma, respectivamente. A análise dos estados representativos de cada região mostrou discrepâncias entre as hospitalizações por asma e as taxas de mortalidade hospitalar por asma. Durante o período de estudo, as hospitalizações por asma custaram US$ 170 milhões ao sistema público de saúde. Embora os óbitos e hospitalizações por asma no Brasil estejam diminuindo desde 2009, os números absolutos ainda são altos, com elevados custos diretos e indiretos para a sociedade, o que mostra a relevância do impacto da asma em países de renda média.

Que hay de nuevo acerca de la inmersion? Un Breve Recorrido por sus Fundamentos y por las Investigaciones Actuales (What's New in Immersion? A Brief Overview of Its Bases and Present-Day Research).

ERIC Educational Resources Information Center

Sierra, Josu

This discussion briefly surveys the development of the immersion method of second language teaching, outlining the central program strategies and characteristics using Curtain's and Pesola's descriptions. An overview of recent research focuses on error correction and feedback studies as an example of pedagogical-methodological evolution in this…

Como Lo Hago Yo: Anomalías del Tubo Neural en Guatemala — Mielomeningocele Unidad de Espina Bífida e Hidrocefalia

PubMed Central

Manucci, Graciela; von Quednow, Enzo

2014-01-01

En Guatemala nacen por añ 786 niños con defectos de tubo neural. Operamos 65 a 70 niños con mielomenigocele por año. Tenemos equipo multidisciplinario. Recomendamos parto por cesárea. Infección antes de la cirugía es un problema mayor. Derivación tardía es un problema. Disecamos la plaqueta con la técnica clásica. Suturamos la plaqueta para restituir la forma de la médula. Corpectomía en casos de cifósis. Hidrocefalía: Operamos el 80% de los niños. Chiari II: Operamos basados en los síntomas, primero nos aseguramos que la válvula funciona bien. Médula anclada: Operamos basados en los síntomas. PMID:24791216

A proposed contents astronomy for basic education

NASA Astrophysics Data System (ADS)

Albrecht, E.; Voelzke, M. R.

2014-08-01

A Astronomia é um tema que sempre exerceu fascínio sobre as pessoas de um modo geral. Conhecer e estudar o que há nos “céus”, além de nossos olhos, continua sendo instigador e de grande interesse. Baseado nestas justificativas desenvolveu-se uma pesquisa de Doutorado, na qual, o objetivo principal foi investigar sobre a presença dos conteúdos de Astronomia nas Propostas Curriculares da região Sul do Brasil, a saber, os estados de Paraná, Rio Grande do Sul e Santa Catarina e, posterior comparação com os Parâmetros Curriculares Nacionais (PCN) que trazem propostas de conteúdos para toda a Educação Básica brasileira. Tal investigação pautou-se na abordagem de caráter qualitativo e utilizouse para tal da Análise de Conteúdos (Bardin, 2011), que possibilitou a construção de quatro categorias, nas quais os conteúdos astronômicos foram agrupados: Terra, Sistema Solar, Via Láctea e Universo. Após a leitura, coleta de dados, construção de categorias, observou-se a dicotomia na apresentação destes conteúdos. As propostas curriculares analisadas foram as de Geografia, Ciências e Física dos estados do Paraná (2008), Rio Grande do Sul (2009) e de Santa Catarina (1998), responsáveis pelo trabalho com Astronomia nestes estados. No Ensino Fundamental, a proposta curricular do estado do Paraná apresenta conteúdos ligados à Astronomia desde o sexto ano até o nono ano, como conteúdo do primeiro bimestre, o que também é apresentado na proposta curricular do estado do Rio Grande do Sul, porém, este, não divide os conteúdos por bimestre e nem por ano, mas por ciclos, sexto e sétimo anos como primeiro ciclo e oitavo e nono anos como segundo ciclo, deixando livre para o professor estruturar sua sequência de conteúdos. A proposta curricular de Santa Catarina não apresenta estes conteúdos de maneira explícita, não divide dos conteúdos nem por ano, nem por série, traz uma sequência de conteúdos para serem trabalhados ao longo dos quatro anos, nos quais, aparecem timidamente alguns conteúdos de Astronomia. Para o Ensino Médio, as propostas curriculares do Paraná e de Santa Catarina parecem que se repetem, apresentando apenas o conteúdo Gravitação Universal, na primeira série do Ensino Médio, já a proposta curricular do Rio Grande do Sul, traz uma sequência que é proposta nos PCN (Brasil, 1998; 1999; 2002), na qual aparece o tema em questão, porém, em todos os anos, em todas as propostas, não há um detalhamento do que, de como trabalhar os conteúdos. O detalhamento facilita a prática pedagógica, pois, conteúdos simples como as Estações do Ano, Fases da Lua, sequer são citados nas propostas curriculares pesquisadas. Outro aspecto observado é que os conteúdos de um modo geral não trazem uma sequência e não primam por partir do entorno do aluno, daquilo que ele conhece para estruturar novos conceitos. Tais aspectos dificultam o fazer pedagógico, pois, por ser uma região com características culturais semelhantes, era esperado que as propostas fossem mais próximas, o! que facilitaria em muito, por exemplo, transferências dentro de um mesmo estado ou interestaduais. Pautando-se no que foi observado, na falta de especificidade dos conteúdos, clareza, sequência dos conteúdos e propostas de trabalho é proposto uma sequência de conteúdos de Astronomia, com materiais e recursos, pois, como apontado por Langhi e Nardi (2009), é necessário fornecer além da informação, do conteúdo, o como fazer. Tal proposta não visa estabelecer-se como regra, mas como suporte ao professor para facilitar sua prática pedagógica e tornar o trabalho com Astronomia presente nas escolas brasileiras. Bardin, L. Análise de conteúdo. Tradução Luís Antero Reto, Augusto Pinheiro. São Paulo: Edições 70, 2011. 279 p. Langhi, R; Nardi, R. Ensino da astronomia no Brasil: educação formal, informal, não-formal e divulgação científica. Revista Brasileira de Ensino de Física, v. 31, n. 4, p. 4402-1 a 4402-11, 2009.

Identification and characterization of smallest pore-forming protein in the cell wall of pathogenic Corynebacterium urealyticum DSM 7109.

PubMed

Abdali, Narges; Younas, Farhan; Mafakheri, Samaneh; Pothula, Karunakar R; Kleinekathöfer, Ulrich; Tauch, Andreas; Benz, Roland

2018-05-09

Corynebacterium urealyticum, a pathogenic, multidrug resistant member of the mycolata, is known as causative agent of urinary tract infections although it is a bacterium of the skin flora. This pathogenic bacterium shares with the mycolata the property of having an unusual cell envelope composition and architecture, typical for the genus Corynebacterium. The cell wall of members of the mycolata contains channel-forming proteins for the uptake of solutes. In this study, we provide novel information on the identification and characterization of a pore-forming protein in the cell wall of C. urealyticum DSM 7109. Detergent extracts of whole C. urealyticum cultures formed in lipid bilayer membranes slightly cation-selective pores with a single-channel conductance of 1.75 nS in 1 M KCl. Experiments with different salts and non-electrolytes suggested that the cell wall pore of C. urealyticum is wide and water-filled and has a diameter of about 1.8 nm. Molecular modelling and dynamics has been performed to obtain a model of the pore. For the search of the gene coding for the cell wall pore of C. urealyticum we looked in the known genome of C. urealyticum for a similar chromosomal localization of the porin gene to known porH and porA genes of other Corynebacterium strains. Three genes are located between the genes coding for GroEL2 and polyphosphate kinase (PKK2). Two of the genes (cur_1714 and cur_1715) were expressed in different constructs in C. glutamicum ΔporAΔporH and in porin-deficient BL21 DE3 Omp8 E. coli strains. The results suggested that the gene cur_1714 codes alone for the cell wall channel. The cell wall porin of C. urealyticum termed PorACur was purified to homogeneity using different biochemical methods and had an apparent molecular mass of about 4 kDa on tricine-containing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Biophysical characterization of the purified protein (PorACur) suggested indeed that cur_1714 is the gene coding for the pore-forming protein in C. urealyticum because the protein formed in lipid bilayer experiments the same pores as the detergent extract of whole cells. The study is the first report of a cell wall channel in the pathogenic C. urealyticum.

Basic Concepts of Astronomy: a Methodological Proposal. (Spanish Title: Conceptos Básicos de Astronomía: Una Propuesta Metodológica.) Conceitos Básicos de Astronomia: Uma Proposta Metodológica

NASA Astrophysics Data System (ADS)

Darroz, Luiz Marcelo; Heineck, Renato; Samudio Pérez, Carlos Ariel

2011-12-01

In this report, the development of a methodological proposal which approaches basic concepts of astronomy-grounded pedagogically on Meaningful Learning is described. The proposal, which consists of four meetings, was developed by teachers and academics of the course of Professor in Physics of the University of Passo Fundo (UPF), through an extension course to a group of highschool students of a public school of the town of Passo Fundo, RS. The work was focused into basic concepts of astronomy. The signs of Meaningful Learning have been obtained by means of research and evaluation tools that were applied at the end of each meeting. The evaluation of the proposal has been conducted by means of a final questionnaire which was answered by the participants at the end ofthe development of activities. By means of the results obtained from the different instruments, and the comments made by the participants during the activities and by means of the high rates of approval obtained in the final questionnaire, we think that the proposal reached the established goals and it may be repeated with the certainty of success. En este relato se describe una propuesta de desarrollo metodológico que aborda conceptos básicos de astronomía fundamentada pedagógicamente en el Aprendizaje Significativo. La propuesta que comprende cuatro encuentros, fue desarrollada por profesores y académicos del curso de Licenciatura en Física de la Universidad de Passo Fundo (UPF), a través de un curso de extensión para un grupo de Liceo del 6º año de una Escuela Pública de la ciudad de Passo Fundo/RS. El trabajo tuvo como eje principal los "conceptos básicos de astronomía". Los indicios de Aprendizaje Significativo fueron obtenidos por instrumentos de pesquisa y evaluación, siempre aplicados después de cada encuentro. La evaluación de la propuesta fue hecha a través de un cuestionario final y contestado por los participantes al finalizar el desarrollo de actividades. Por los resultados obtenidos en diferentes momentos, por los comentarios efectuados por los participantes durante las actividades y por los altos índices de aprobación al final de la etapa, consideramos que la propuesta atingió los objetivos establecidos y puede ser repetida con certeza de éxito. Neste relato, descreve-se o desenvolvimento de uma proposta metodológica que aborda conceitos básicos de astronomia fundamentada pedagogicamente na Aprendizagem Significativa. A proposta, que compreende quatro encontros, foi desenvolvida por professores e acadêmicos do curso de Licenciatura em Física da Universidade de Passo Fundo (UPF), através de um curso de extensão, a um grupo de dez estudantes do ensino médio de uma escola pública da cidade de Passo Fundo, RS. O trabalho centrou-se em conceitos básicos de astronomia. Os indícios da aprendizagem significativa foram obtidos por instrumentos de pesquisa e avaliação aplicados ao término de cada encontro. A avaliação da proposta foi efetuada através de um questionário final respondido pelos participantes ao término do desenvolvimento das atividades. Pelos resultados obtidos nos diferentes instrumentos, pelos comentários efetuados pelos participantes durante as atividades e pelos altos índices de aprovação alcançados no questionário final, consideramos que a proposta atingiu os objetivos estabelecidos e pode ser repetida com convicção de sucesso.

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Por encargo del Secretario Abraham, la Oficina de Eficiencia Energética y Energía Renovable suministra el liderazgo a nivel nacional para impulsar las tecnologías de eficiencia energética y energía renovables, para saltar por encima de las limitaciones del status quo, y para alcanzar beneficios ambientales notables. El Programa de Tecnologías Geotérmicas, parte crítica de nuestro esfuerzo conjunto, está avanzando a grandes zancadas para aumentar la viabilidad y el despliegue de electricidad ...

Strengthening North American Security: A Strategy to Engage Mexico

DTIC Science & Technology

2005-04-01

Secretaría de Comunicaciones y Transportes de México para ejercer más presión sobre SEDENA para que participe en NORAD. Incluso si SEDENA optara por no...participar, NORAD aún puede perseguir la iniciativa de intercambio de información por separado con la Secretaría de Comunicaciones y Transportes...Secretariat of Communication & Transportation Secretaría de Comunicaciones y Transportes Strategy Estrategia No loss of Mexican sovereignty No hay

See the World on the Internet: Tips for Parents of Young Readers--and "Surfers" = Vea el mundo por Internet: Ideas por padres de jovenes lectores y exploradores.

ERIC Educational Resources Information Center

Moss, Jeanette

Regardless of whether a parent has Internet access at home, it is essential that parents learn with their children and be aware of where their travels on the Internet are taking them. Many libraries have Internet workshops for parents or children or both. In the excitement of looking at sites, children may not even realize they are reading. Many…

Riego y fertirriego

Treesearch

R. Kasten Dumroese; Thomas D. Landis; Kim M. Wilkinson

2012-01-01

El agua es el factor que más puede afectar el crecimiento y la sanidad de las plantas por sí solo. Es esencial para casi todos los procesos vegetales: la fotosíntesis, el transporte de nutrientes, el crecimiento y el desarrollo celular. De hecho, del 80 al 90% del peso de un plantín es agua, por lo cual el manejo del riego es una de las tareas más trascendentes dentro...

Enzymology below 200 K: The kinetics and thermodynamics of the photochemistry catalyzed by protochlorophyllide oxidoreductase

PubMed Central

Heyes, Derren J.; Ruban, Alexander V.; Wilks, Helen M.; Hunter, C. Neil

2002-01-01

The chlorophyll biosynthesis enzyme protochlorophyllide reductase (POR) catalyzes the light-dependent reduction of protochlorophyllide (Pchlide) into chlorophyllide in the presence of NADPH. As POR is light-dependent, catalysis can be initiated by illumination of the enzyme-substrate complex at low temperatures, making it an attractive model for studying aspects of biological proton and hydride transfers. The early stages in the photoreduction, involving Pchlide binding and an initial photochemical reaction, have been studied in vitro by using low-temperature fluorescence and absorbance measurements. Formation of the ternary POR-NADPH-Pchlide complex produces red shifts in the fluorescence and absorbance maxima of Pchlide, allowing the dissociation constant for Pchlide binding to be measured. We demonstrate that the product of an initial photochemical reaction, which can occur below 200 K, is a nonfluorescent intermediate with a broad absorbance band at 696 nm (A696) that is suggested to represent an ion radical complex. The temperature dependence of the rate of A696 formation has allowed the activation energy for the photochemical step to be calculated and has shown that POR catalysis can proceed at much lower temperatures than previously thought. Calculations of differences in free energy between various reaction intermediates have been calculated; these, together with the quantum efficiency for Pchlide conversion, suggest a quantitative model for the thermodynamics of the light-driven step of Pchlide reduction. PMID:12177453

Identification of specific posttranslational O-mycoloylations mediating protein targeting to the mycomembrane.

PubMed

Carel, Clément; Marcoux, Julien; Réat, Valérie; Parra, Julien; Latgé, Guillaume; Laval, Françoise; Demange, Pascal; Burlet-Schiltz, Odile; Milon, Alain; Daffé, Mamadou; Tropis, Maryelle G; Renault, Marie A M

2017-04-18

The outer membranes (OMs) of members of the Corynebacteriales bacterial order, also called mycomembranes, harbor mycolic acids and unusual outer membrane proteins (OMPs), including those with α-helical structure. The signals that allow precursors of such proteins to be targeted to the mycomembrane remain uncharacterized. We report here the molecular features responsible for OMP targeting to the mycomembrane of Corynebacterium glutamicum , a nonpathogenic member of the Corynebacteriales order. To better understand the mechanisms by which OMP precursors were sorted in C. glutamicum , we first investigated the partitioning of endogenous and recombinant PorA, PorH, PorB, and PorC between bacterial compartments and showed that they were both imported into the mycomembrane and secreted into the extracellular medium. A detailed investigation of cell extracts and purified proteins by top-down MS, NMR spectroscopy, and site-directed mutagenesis revealed specific and well-conserved posttranslational modifications (PTMs), including O -mycoloylation, pyroglutamylation, and N -formylation, for mycomembrane-associated and -secreted OMPs. PTM site sequence analysis from C. glutamicum OMP and other O -acylated proteins in bacteria and eukaryotes revealed specific patterns. Furthermore, we found that such modifications were essential for targeting to the mycomembrane and sufficient for OMP assembly into mycolic acid-containing lipid bilayers. Collectively, it seems that these PTMs have evolved in the Corynebacteriales order and beyond to guide membrane proteins toward a specific cell compartment.

Identification of specific posttranslational O-mycoloylations mediating protein targeting to the mycomembrane

PubMed Central

Carel, Clément; Réat, Valérie; Parra, Julien; Latgé, Guillaume; Laval, Françoise; Burlet-Schiltz, Odile; Milon, Alain; Daffé, Mamadou; Tropis, Maryelle G.; Renault, Marie A. M.

2017-01-01

The outer membranes (OMs) of members of the Corynebacteriales bacterial order, also called mycomembranes, harbor mycolic acids and unusual outer membrane proteins (OMPs), including those with α-helical structure. The signals that allow precursors of such proteins to be targeted to the mycomembrane remain uncharacterized. We report here the molecular features responsible for OMP targeting to the mycomembrane of Corynebacterium glutamicum, a nonpathogenic member of the Corynebacteriales order. To better understand the mechanisms by which OMP precursors were sorted in C. glutamicum, we first investigated the partitioning of endogenous and recombinant PorA, PorH, PorB, and PorC between bacterial compartments and showed that they were both imported into the mycomembrane and secreted into the extracellular medium. A detailed investigation of cell extracts and purified proteins by top-down MS, NMR spectroscopy, and site-directed mutagenesis revealed specific and well-conserved posttranslational modifications (PTMs), including O-mycoloylation, pyroglutamylation, and N-formylation, for mycomembrane-associated and -secreted OMPs. PTM site sequence analysis from C. glutamicum OMP and other O-acylated proteins in bacteria and eukaryotes revealed specific patterns. Furthermore, we found that such modifications were essential for targeting to the mycomembrane and sufficient for OMP assembly into mycolic acid-containing lipid bilayers. Collectively, it seems that these PTMs have evolved in the Corynebacteriales order and beyond to guide membrane proteins toward a specific cell compartment. PMID:28373551

The effects of telemedicine on racial and ethnic disparities in access to acute stroke care.

PubMed

Lyerly, Michael J; Wu, Tzu-Ching; Mullen, Michael T; Albright, Karen C; Wolff, Catherine; Boehme, Amelia K; Branas, Charles C; Grotta, James C; Savitz, Sean I; Carr, Brendan G

2016-03-01

Racial and ethnic disparities have been previously reported in acute stroke care. We sought to determine the effect of telemedicine (TM) on access to acute stroke care for racial and ethnic minorities in the state of Texas. Data were collected from the US Census Bureau, The Joint Commission and the American Hospital Association. Access for racial and ethnic minorities was determined by summing the population that could reach a primary stroke centre (PSC) or telemedicine spoke within specified time intervals using validated models. TM extended access to stroke expertise by 1.5 million residents. The odds of providing 60-minute access via TM were similar in Blacks and Whites (prevalence odds ratios (POR) 1.000, 95% CI 1.000-1.000), even after adjustment for urbanization (POR 1.000, 95% CI 1.000-1.001). The odds of providing access via TM were also similar for Hispanics and non-Hispanics (POR 1.000, 95% CI 1.000-1.000), even after adjustment for urbanization (POR 1.000, 95% CI 1.000-1.000). We found that telemedicine increased access to acute stroke care for 1.5 million Texans. While racial and ethnic disparities exist in other components of stroke care, we did not find evidence of disparities in access to the acute stroke expertise afforded by telemedicine. © The Author(s) 2015.

Modos de produccion cientifica: Culturas y metodologias de investigacion en la Universidad de Cadiz

NASA Astrophysics Data System (ADS)

Gonzalez Ramos, Ana M.

2004-12-01

Este trabajo de investigacion supone un modelo teorico de caracter aplicado, que proporciona la oportunidad de evaluar la produccion cientifica de los investigadores. Se encuadra dentro de la tradiccion de la estadistica aplicada y la sociologia del conocimiento. Atiende especialmente a dos conjuntos de temas de interes, por una parte, las caracteristicas principales que determinan el nivel y tipo de produccion academica producida por las unidades de investigacion y por los propios investigadores; por otra, la utilizacion que se hace de los metodos y tecnicas de investigacion puesto que de ello tambien depende el modo de produccion cientifica. Los puntos novedosos de esta tesis son: la medicion cuantitativa del objeto de estudio, la suma de los productos y las condiciones externas a la produccion del conocimiento mas otros elementos internos como las caracteristicas de los investigadores y la metodologia utilizada para desarrollar sus trabajos; y, finalmente, el uso de las nuevas tecnologias. El aprovechamiento de los recursos estadisticos y las fuentes de informacion secundarias se complementan con el diseno propio de una encuesta donde se implementa las caracteristicas descritas en un capitulo anterior sobre los metodos cientificos mas idoneos descritos en los principales manuales y articulos cientificos desde distintas disciplinas de conocimiento. Dicha encuesta ha sido desarrollada como un programa propio y en base a los mas innovadores usos de la tecnologia en la metodologia de encuestas.

Pincharse sin infectarse: estrategias para prevenir la infección por el VIH y el VHC entre usuarios de drogas inyectables

PubMed Central

MATEU-GELABERT, P.; FRIEDMAN, S.; SANDOVAL, M.

2011-01-01

Resumen Objetivo Desde principios de los noventa, en la ciudad de Nueva York se han implementado con éxito programas para reducir la incidencia del virus de la inmunodeficiencia humana (VIH) y, en menor medida, del virus de la hepatitis C (VHC). A pesar de ello, aproximadamente el 70% de los usuario de drogas inyectables (UDI) están infectados por el VHC. Queremos investigar cómo el 30% restante se las ha arreglado para no infectarse. El Staying safe (nombre original del estudio) explora los comportamientos y mecanismos que ayudan a evitar la infección por el VHC y el VIH a largo plazo. Material y métodos Hemos utilizado el concepto de «desviación positiva» aplicado en otros campos de salud pública. Estudiamos las estrategias, prácticas y tácticas de prevención de aquellos UDI que, viviendo en contextos de alta prevalencia, se mantienen sin infectar por VIH y el VHC, a pesar de haberse inyectado heroína durante años. Los resultados preliminares presentados en este artículo incluyen el análisis de las entrevistas realizadas a 25 UDI (17 doble negativos, 3 doble positivos y 5 con infección por el VHC y sin infección por el VIH). Se usaron entrevistas semiestructuradas que exploraban con detalle la historia de vida de los sujetos, incluyendo su consumo de drogas, redes sociales, contacto con instituciones, relaciones sexuales y estrategias de protección y vigilancia. Resultados La intencionalidad es importante para no infectarse, especialmente durante períodos de involución (períodos donde hay un deterioro económico y/o social que llevan al que se inyecta a situaciones de mayor riesgo). Presentamos tres dimensiones independientes de intencionalidad que conllevan comportamientos que pueden ayudar a prevenir la infección: a) evitar «el mono» (síntomas de abstención) asegurando el acceso a la droga; b) «llevarlo bien» para no convertirse en un junkie y así evitar la «muerte social» y la falta de acceso a los recursos, y c) seguir sin infectarse por el VIH (sólo un doble negativo tuvo un amplio conocimiento sobre la hepatitis C). Estas intencionalidades no son mutuamente excluyentes. La presencia de varias refuerza la puesta en práctica a diario de comportamientos que pueden ayudar al que se inyecta a mantenerse libre de infecciones durante años. Algunas prácticas que hemos identificado se implementan en grupo y se comunican de UDI a UDI, de esta manera se extienden entre algunas redes sociales de UDI. Conclusiones Los UDI que permanecen sin infectarse planean e implementan estrategias de prevención en circunstancias donde otros UDI aplican prácticas de riesgo. El mantenimiento de la no infección no es, por lo tanto, un resultado del azar, sino más bien el resultado del esfuerzo (agencia) de los UDI. Investigar y extender estas estrategias y tácticas a través de programas de prevención podría contribuir a la prevención del VIH y el VHC. PMID:21915175

Effect of endotoxin on the expression of GnRH and GnRHR genes in the hypothalamus and anterior pituitary gland of anestrous ewes.

PubMed

Herman, Andrzej Przemysław; Tomaszewska-Zaremba, Dorota

2010-07-01

An immune/inflammatory challenge can affect reproduction at the level of the hypothalamus, pituitary gland, or gonads. Nonetheless, the major impact is thought to occur within the brain or the pituitary gland. The present study was designed to examine the effect of intravenous (i.v.) lipopolysaccharide (LPS) injection on the expression of gonadotropin-releasing hormone (GnRH) and the gonadotropin-releasing hormone receptor (GnRHR) genes in the hypothalamic structures where GnRH neurons are located as well as in the anterior pituitary gland (AP) of anestrous ewes. We also determined the effect of LPS on luteinizing hormone (LH) release. It was found that i.v. LPS injection significantly decreased GnRH and GnRHR mRNAs levels in the preoptic area (40%, p

Gonococcal Resistance to β-Lactams and Tetracycline Involves Mutation in Loop 3 of the Porin Encoded at the penB Locus

PubMed Central

Gill, M. J.; Simjee, S.; Al-Hattawi, K.; Robertson, B. D.; Easmon, C. S. F.; Ison, C. A.

1998-01-01

penB is a chromosomal mutation that confers resistance to β-lactams and tetracyclines and reduced susceptibility to quinolones in Neisseria gonorrhoeae. It is linked to the porin gene (por) and requires the increased expression of an efflux pump due to mtr. Transformation of a susceptible gonococcus (strain H1) with chromosomal DNA from strain FA140 (penA mtr penB; porin serovar IB1) and conjugal transfer of a β-lactamase-expressing plasmid was used to produce isogenic strains for determination of equilibrium periplasmic penicillin concentrations by the method of Zimmermann and Rosselet (W. Zimmermann and A. Rosselet, Antimicrob. Agents Chemother. 12:368–372, 1977). In transformants with the Mtr and PenB phenotypes, equilibrium concentrations of penicillin were reduced. DNA sequence analysis of por from isogenic penB and penB+ transformants revealed 14 sequence differences; nine of these differences resulted in amino acid changes. Three amino acid changes were found in the putative gonococcal equivalent of the pore-constricting loop 3 of Escherichia coli OmpF. Two of these changes (Gly-101–Ala-102→Asp-Asp) result in an increased negative charge at this position in por loop 3. PCR products comprising the complete por gene from strain FA140 were transformed into strain H1-2 (penA mtr; porin serovar IB-3), with the resulting transformants having the antibiotic susceptibility phenotype associated with penB. penB-like mutations were found in loop 3 of clinical isolates of gonococci with chromosomally mediated resistance to penicillin. We conclude that penB is a mutation in loop 3 of por that reduces porin permeability to hydrophilic antibiotics and plays an important role in the development of chromosomally mediated resistance to penicillin and tetracycline in gonococci. PMID:9797206

Effect of follicular flushing on reproductive outcomes in patients with poor ovarian response undergoing assisted reproductive technology.

PubMed

Souza, Anna L M; Sampaio, Marcos; Noronha, Graciele B; Coster, Ludiana G R; de Oliveira, Roberta S G; Geber, Selmo

2017-10-01

The purpose of this study is to investigate the impact of follicular flushing on the number of oocytes retrieved, oocyte maturity, fertilization rate, embryo development, and pregnancy rate of poor ovarian responders (POR). Retrospective study of 524 cycles of 384 patients with POR submitted to assisted reproductive technology (ART) and who had follicular flushing during oocyte retrieval was used in the study. We included patients with <5 oocytes at oocyte retrieval (POR group) and matching the Bologna criteria. POR patients had a mean age of 38.2 ± 4.2 years. A total of 1355 follicles (mean = 3.5 ± 1.6) were aspirated and 1040 oocytes recovered, with 709 (68.2%) obtained by direct aspiration and 331 (31.8%) by follicular flushing. We found a difference between the total number of oocytes and the number of aspirated oocytes. Overall pregnancy rate was 22%. Association was observed between pregnancy rate and the number of oocytes retrieved, the number of MII oocytes, and the number of embryos transferred. The patients matching the Bologna criteria had a mean age of 38.9 ± 3.9 years. A total of 309 follicles were aspirated (mean = 3.1 ± 1.5) and 242 oocytes recovered, with 156 (64.5%) obtained by direct aspiration and 86 (35.5%) by follicular flushing. There was a significant difference between the total number of oocytes and the number of aspirated oocytes. Overall pregnancy rate was 12.1%. There was no association between the pregnancy rate and the number of oocytes retrieved, the number of MII, and the number of embryos. Follicular flushing might be a suitable alternative to increase the number of oocytes and pregnancy rates in patients with POR.

PubMed

Medina Arnaudo, Gisel Ivana

2017-09-08

Resumen: La valoración del Índice de Filtrado Glomerular (IFG) es fundamental para la selección de potenciales donantes renales. Para su medición existen métodos poco prácticos y complejos, por lo cual se han desarrollado ecuaciones de estimación del IFG. Objetivo: Evaluar el rendimiento diagnóstico de ecuaciones de estimación del IFG a partir de Creatinina y Cistatina C en una población de adultos sanos candidatos a donantes renales. Materiales y métodos: Se llevó a cabo un estudio transversal en 72 pacientes de ambos sexos de entre 18 y 75 años de edad, candidatos a donantes renales. Se les midió el IFG a través del clearance de Iotalamato no marcado (IFGm). Se evaluaron cuatro ecuaciones de estimación del FG (IFGe): MDRD, del estudio "Modification of Diet in Renal Disease"; CKD-EPI-Creatinina (CKD-EPI-CREAT) y CKD-EPI-Creatinina y Cistatina C (CKD-EPI-CREAT+CIS), desarrolladas por el grupo "Chronic Kidney Disease Epidemiology Collaboration"; y la que incluye Creatinina y Cistatina C propuesta por Stevens y col. (STEVENS-CREAT+CIS). Se analizó el desempeño de cada ecuación con respecto al IFGm. Resultados: Las ecuaciones CKD-EPI-CREAT+CIS, STEVENS-CREAT+CIS y CKD-EPI-CREAT mostraron ser más exactas (bias= 1,93; -0,71; -1,53 mL/min/1,73m2 respectivamente) que MDRD (bias= -10,36 mL/min/1,73m2). El mejor rendimiento diagnóstico lo mostró  el IFGe CKD-EPI-CREAT+CIS (LR(+)=9,8; "Positive Likelihood Ratios"), seguido por IFGe STEVENS-CREAT+CIS (LR(+)=4,7) y luego por IFGe CKD-EPI-CREAT (LR(+)=3,7). Discusión: Las ecuaciones CKD-EPI-CREAT+CIS, STEVENS-CREAT+CIS y CKD-EPI-CREAT demostraron tener un desempeño claramente superior a MDRD para estimar el IFG en la población estudiada.

Diabetes is associated with chronic liver disease and liver cancer in the adult population of Puerto Rico.

PubMed

Ortiz, Ana P; Romero, Carlos; Disdier, Orville; Santana, Erik; Torres, Margaret; Torres, Esther A; Pérez, Cynthia M

2011-09-01

Diabetes mellitus (DM) has been proposed as a risk factor for both chronic liver disease (CLD) and for hepatocellular carcinoma (HCC); however, studies among Hispanics are limited. Puerto Rico (PR) has a high prevalence of DM (13%), supporting the need for a better understanding of the public health implications associated with DM in this population. We assessed the association of DM with CLD and with HCC in a population of Puerto Rican adults with health insurance. The study sample consisted of 1,040,025 individuals, aged > or = 18 years, all covered by the government-run healthcare program in PR, in 2002. The ICD-9 codes for DM, CLD, and HCC were obtained in order to determine the prevalence of these conditions. Logistic regression models were used to determine the association of DM with CLD and with HCC, after adjusting for covariates. The prevalence of DM was higher in patients with CLD (17%) and those with HCC (18%) than it was in patients without either of these conditions (8% and 7%, respectively). Among women, those with DM were significantly more likely to have CLD than were those without DM (POR: 35-49 yrs: 3.26, 95% CI = 2.12, 5.00; POR: 50-64 yrs: 2.10, 95% CI = 1.63, 2.71; POR: > or = 65 yrs: 2.33, 95% CI = 1.67, 3.25). Among men, those with DM were more likely to have CLD than were those without DM; this association was significant among males aged 50-64 (POR: 1.30, 95% CI = 1.03-1.63) and those aged > or = 65 yrs (POR: 1.94, 95% CI = 1.35-2.80). Consistent with other studies, we observed a strong association of DM with CLD and HCC. In order to reduce the burden of these conditions in PR, research and public health efforts should be concentrated on gaining a better understanding of these associations.

[Not Available].

PubMed

Angulo, Daniela; Bustos, Edson; Sánchez, Andrés; Barja, Salesa

2016-07-19

Introducción: la rehabilitación de la alimentación por vía oral (RVO) es compleja en pacientes que han recibido nutrición enteral (NE) prolongada. Objetivo: describir este proceso en niños con enfermedades respiratorias crónicas y sonda nasoenteral (SNE) o gastrostomía (GT).Pacientes y métodos: estudio retrospectivo con revisión de registros clínicos de niños con NE mayor a dos meses, ingresados entre 2005 y 2014 al Hospital Josefina Martínez.Resultados: Se incluyeron 116 pacientes, con mediana de edad 10 meses (Rango: 3 a 101), 56% hombres. Diagnóstico: 34,5% Daño pulmonar crónico postinfeccioso (DPC), 29,3% Insuficiencia respiratoria por enfermedad neuromuscular, 19% Displasia broncopulmonar y 17,2% enfermedad de la vía aérea. Con traqueostomía: 82,8%. Eran usuarios de GT 89,7% y de SNG 10,3%, instaladas con mediana de edad 6 meses (0 a 74), por ingesta insuficiente (6,6%) o trastorno de deglución (92,4%). Del grupo total, 36,2% (42/116) tenía indicación de RVO, los cuales habían recibido NE durante 12,2 meses (2 a 41); de estos 50% (21/42) logró alimentarse exclusivamente por vía oral (91% SNG y 35,4% GT, Chi2 p = 0,023), 14% parcialmente y 36% no lo logró. El tiempo para lograr la vía oral exclusiva fue de 9,75 meses (0,5 a 47), sin diferencia por edad, sexo, vía de acceso, duración NE ni presencia de enfermedad neurológica.Conclusión: en pacientes con enfermedades respiratorias crónicas graves y NE prolongada, la RVO es un proceso lento pero posible: 64% lo logra de modo completo o parcial.

La Aventura de las Partículas

Science.gov Websites

ciertas formas fundamentales. Explore las siguientes rutas que le explicarán la materia del universo! La grande del logo de la Ruta SM) La ruta de las evidencias experimentales : aprenda como los físicos diseà explicación de los "por qué" de las interacciones físicas hay todavía muchos misterios por

DNA Vaccination of the American Crow (Corvus brachyrhynchos) Provides Partial Protection Against Lethal Challenge with West Nile Virus

DTIC Science & Technology

2007-01-01

mortality but did not provide sterile immunity. RESUMEN. La vacunación del cuervo Americano (Corvus brachyrhynchos) con vacuna de ADN proporciona...casi 100% fatal en el cuervo Americano (Corvus brachyrhynchos). Evaluamos cuatro formulaciones de vacunas en cuervos Americanos, incluyendo una vacuna de...ADN, una vacuna de ADN con adyuvante, ambas aplicadas por la vı́a intramuscular, una vacuna de ADN microencapsulada aplicada por la vı́a oral, y una

Relationship between Spain and the United States during the 18th and 19th Centuries

DTIC Science & Technology

1990-03-21

buiena correspandencis pars lo sucesivo; y si esta se difiriese a quando hubiese salida dle sus aprielas, ni sot voluntad estaria tan bien dispuesta, ni...ndidndase a voluntad . se podrdn internar hacia nuestres posesiones par [a espalda de Is Luisisna. H-ay que tcner presente quc el rio San Larenzo por el...serd en su mano on poderoso ynstrumento. pars menearlo a so voluntad contra dichas naciones: y que Wse no quedara sin exercicia, por mocha tiempo nadie

Antimicrobial susceptibility of Salmonella isolates from healthy pigs and chickens (2008-2011).

PubMed

de Jong, Anno; Smet, Annemieke; Ludwig, Carolin; Stephan, Bernd; De Graef, Evelyne; Vanrobaeys, Mia; Haesebrouck, Freddy

2014-07-16

Using the agar dilution method, antimicrobial susceptibility to human-use antibiotics was determined among Belgian faecal Salmonella isolates from healthy pigs and broiler chickens. Both epidemiological cut-off values and clinical breakpoints were applied for interpretation of the results. Cephalosporin-resistant isolates were examined for the presence of genes encoding CTX-M, SHV, TEM and CMY β-lactamases. All isolates with decreased quinolone susceptibility were screened for plasmid-borne genes qnr, qepA and aac(6')-Ib-cr. In all, 368 Salmonella isolates were recovered from pigs and 452 from chickens. Clinical resistance to ciprofloxacin was absent in isolates of both host species, and was 1.9 and 13.1% to cefotaxime in pig and poultry isolates, respectively. Decreased susceptibility to cefotaxime amounted to 2.2 and 0.7%, whereas for ciprofloxacin this was 3.0 and 23.0% in pig and poultry isolates, respectively. Ciprofloxacin decreased susceptibility was limited to few serovars, mainly Paratyphi B. Multidrug resistance was markedly higher for pig isolates (39.7%) than for chicken isolates (17.3%). Sixty-six cefotaxime-resistant isolates, 59 from chickens and 7 from pigs, were phenotypically determined as ESBL/AmpC producers; predominantly Paratyphi B and Typhimurium serovars. BlaCTX-M (mostly blaCTXM-1, but also blaCTXM-2 and blaCTXM-9) and blaTEM-52 were the predominant ESBL genes. Only few isolates expressed SHV-12 or an AmpC enzyme (CMY-2). Isolates of four serovars carried qnr genes: Brandenburg and Llandof from pigs, both qnrS; Indiana and Paratyphi B from chickens with qnrB and qnrA. The latter isolate carried blaCTX-M-9 and was the only strain with a plasmid-borne quinolone resistance gene among the ESBL/AmpC producers. This Salmonella survey confirms that the ESBL/AmpC producers are particularly prevalent in chickens (12.8%), and much less in pigs (1.9%). A link between plasmid-borne quinolone resistance genes and ESBLs/AmpC was uncommon. Copyright © 2014 Elsevier B.V. All rights reserved.

Bioaccumulation of pharmaceuticals and other anthropogenic waste indicators in earthworms from agricultural soil amended with biosolid or swine manure

USGS Publications Warehouse

Kinney, C.A.; Furlong, E.T.; Kolpin, D.W.; Burkhardt, M.R.; Zaugg, S.D.; Werner, S.L.; Bossio, J.P.; Benotti, M.J.

2008-01-01

Analysis of earthworms offers potential for assessing the transfer of organic anthropogenic waste indicators (AWIs) derived from land-applied biosolid or manure to biota. Earthworms and soil samples were collected from three Midwest agricultural fields to measure the presence and potential for transfer of 77 AWIs from land-applied biosolids and livestock manure to earthworms. The sites consisted of a soybean field with no amendments of human or livestock waste (Site 1), a soybean field amended with biosolids from a municipal wastewater treatment plant (Site 2), and a cornfield amended with swine manure (Site 3). The biosolid applied to Site 2 contained a diverse composition of 28 AWIs, reflecting the presence of human-use compounds. The swine manure contained 12 AWIs, and was dominated by biogenic sterols. Soil and earthworm samples were collected in the spring (about 30 days after soil amendment) and fall (140-155 days after soil amendment) at all field sites. Soils from Site 1 contained 21 AWIs and soil from Sites 2 and 3 contained 19 AWIs. The AWI profiles at Sites 2 and 3 generally reflected the relative composition of AWIs present in waste material applied. There were 20 AWIs detected in earthworms from Site 1 (three compounds exceeding concentrations of 1000 ??g/kg), 25 AWIs in earthworms from Site 2 (seven compounds exceeding concentrations of 1000 ??g/kg), and 21 AWIs in earthworms from Site 3 (five compounds exceeding concentrations of 1000 ??g/kg). A number of compounds thatwere present in the earthworm tissue were at concentrations less than reporting levels in the corresponding soil samples. The AWIs detected in earthworm tissue from the three field sites included pharmaceuticals, synthetic fragrances, detergent metabolites, polycyclic aromatic hydrocarbons (PAHs), biogenic sterols, disinfectants, and pesticides, reflecting a wide range of physicochemical properties. For those contaminants detected in earthworm tissue and soil, bioaccumulation factors (BAF) ranged from 0.05 (galaxolide) to 27 (triclosan). This study documents that when AWIs are present in source materials that are land applied, such as biosolids and swine manure, AWIs can be transferred to earthworms. ?? 2008 American Chemical Society.

Humans Strengthen Bottom-Up Effects and Weaken Trophic Cascades in a Terrestrial Food Web

PubMed Central

Muhly, Tyler B.; Hebblewhite, Mark; Paton, Dale; Pitt, Justin A.; Boyce, Mark S.; Musiani, Marco

2013-01-01

Ongoing debate about whether food webs are primarily regulated by predators or by primary plant productivity, cast as top-down and bottom-up effects, respectively, may becoming superfluous. Given that most of the world's ecosystems are human dominated we broadened this dichotomy by considering human effects in a terrestrial food-web. We studied a multiple human-use landscape in southwest Alberta, Canada, as opposed to protected areas where previous terrestrial food-web studies have been conducted. We used structural equation models (SEMs) to assess the strength and direction of relationships between the density and distribution of: (1) humans, measured using a density index; (2) wolves (Canis lupus), elk (Cervus elpahus) and domestic cattle (Bos taurus), measured using resource selection functions, and; (3) forage quality, quantity and utilization (measured at vegetation sampling plots). Relationships were evaluated by taking advantage of temporal and spatial variation in human density, including day versus night, and two landscapes with the highest and lowest human density in the study area. Here we show that forage-mediated effects of humans had primacy over predator-mediated effects in the food web. In our parsimonious SEM, occurrence of humans was most correlated with occurrence of forage (β = 0.637, p<0.0001). Elk and cattle distribution were correlated with forage (elk day: β = 0.400, p<0.0001; elk night: β = 0.369, p<0.0001; cattle day: β = 0.403, p<0.0001; cattle, night: β = 0.436, p<0.0001), and the distribution of elk or cattle and wolves were positively correlated during daytime (elk: β = 0.293, p <0.0001, cattle: β = 0.303, p<0.0001) and nighttime (elk: β = 0.460, p<0.0001, cattle: β = 0.482, p<0.0001). Our results contrast with research conducted in protected areas that suggested human effects in the food web are primarily predator-mediated. Instead, human influence on vegetation may strengthen bottom-up predominance and weaken top-down trophic cascades in ecosystems. We suggest that human influences on ecosystems may usurp top-down and bottom-up effects. PMID:23667705

Conserving tigers in working landscapes.

PubMed

Chanchani, Pranav; Noon, Barry R; Bailey, Larissa L; Warrier, Rekha A

2016-06-01

Tiger (Panthera tigris) conservation efforts in Asia are focused on protected areas embedded in human-dominated landscapes. A system of protected areas is an effective conservation strategy for many endangered species if the network is large enough to support stable metapopulations. The long-term conservation of tigers requires that the species be able to meet some of its life-history needs beyond the boundaries of small protected areas and within the working landscape, including multiple-use forests with logging and high human use. However, understanding of factors that promote or limit the occurrence of tigers in working landscapes is incomplete. We assessed the relative influence of protection status, prey occurrence, extent of grasslands, intensity of human use, and patch connectivity on tiger occurrence in the 5400 km(2) Central Terai Landscape of India, adjacent to Nepal. Two observer teams independently surveyed 1009 km of forest trails and water courses distributed across 60 166-km(2) cells. In each cell, the teams recorded detection of tiger signs along evenly spaced trail segments. We used occupancy models that permitted multiscale analysis of spatially correlated data to estimate cell-scale occupancy and segment-scale habitat use by tigers as a function of management and environmental covariates. Prey availability and habitat quality, rather than protected-area designation, influenced tiger occupancy. Tiger occupancy was low in some protected areas in India that were connected to extensive areas of tiger habitat in Nepal, which brings into question the efficacy of current protection and management strategies in both India and Nepal. At a finer spatial scale, tiger habitat use was high in trail segments associated with abundant prey and large grasslands, but it declined as human and livestock use increased. We speculate that riparian grasslands may provide tigers with critical refugia from human activity in the daytime and thereby promote tiger occurrence in some multiple-use forests. Restrictions on human-use in high-quality tiger habitat in multiple-use forests may complement existing protected areas and collectively promote the persistence of tiger populations in working landscapes. © 2015 Society for Conservation Biology.

Study of the interaction mechanisms between absorbed NO{sub 2} and por-Si/SnO{sub x} nanocomposite layers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolotov, V. V.; Kan, V. E., E-mail: kan@obisp.oscsbras.ru; Makushenko, R. K.

2013-10-15

The interaction mechanisms between NO{sub 2} molecules and the surface of por-Si/SnO{sub x} nanocomposites obtained by magnetron deposition and chemical vapor deposition (CVD) are studied by infrared absorption spectroscopy and electron paramagnetic resonance methods. The observed increase in the free carrier concentration in the por-Si/SnO{sub x} nanocomposite layers is explained by a change in the charge state of P{sub b} centers due to the formation of neutral 'surface defect-adsorbed NO{sub 2} molecule' complexes with free carrier generation in the crystallite bulk. In the nanocomposite layers grown by the CVD method, the increase in the free hole concentration during NO{sub 2}more » adsorption is much less pronounced in comparison with the composite grown by magnetron deposition, which is caused by the competing interaction channel of NO{sub 2} molecules with electrically neutral P{sub b} centers.« less

A importância de reconhecer a síndrome antifosfolípide na medicina vascular

PubMed Central

Funke, Andreas; Danowski, Adriana; de Andrade, Danieli Castro Oliveira; Rêgo, Jozelia; Levy, Roger Abramino

2017-01-01

Resumo A síndrome antifosfolipíde (SAF) é uma doença autoimune sistêmica caracterizada por trombose arterial ou venosa recorrente e/ou morbidade gestacional e pela presença dos anticorpos antifosfolipídeos, podendo apresentar outras manifestações vasculares, como microangiopatia, arteriopatia crônica e SAF catastrófica. Determinados testes laboratoriais para a síndrome (por exemplo, o anticoagulante lúpico) podem sofrer interferência do uso de medicações anticoagulantes, dificultando o diagnóstico. A fisiopatologia da SAF é complexa, sendo enumerados no texto diversos mecanismos patogênicos relacionados à coagulação, ao endotélio e às plaquetas. Por fim, discutimos o tratamento da SAF de acordo com a presença e o tipo de manifestações clínicas, o uso dos anticoagulantes orais diretos e o manejo perioperatório de pacientes com SAF. PMID:29930638

Trombose venosa profunda e vírus chicungunha

PubMed Central

Marques, Marcos Arêas; Adami de Sá, Fernanda Penza; Lupi, Otília; Brasil, Patricia; von Ristow, Arno

2017-01-01

Resumo Algumas infecções virais sistêmicas podem estar relacionadas ao desenvolvimento de trombose venosa profunda e/ou embolia pulmonar. Essa associação já está bem descrita em pacientes com infeções pelo vírus da imunodeficiência humana (HIV), hepatite C ou influenza. Recentemente introduzido no continente americano, o vírus chicungunha, agente etiológico da febre de chicungunha, ainda não tem essa relação bem sedimentada, mas com o aumento progressivo de sua incidência e pelo fato dessa infecção causar, muitas vezes, uma restrição severa da locomoção por poliartralgia e uma possível lesão endotelial direta, casos de tromboembolismo venoso podem começar a ser descritos. Neste relato de caso, descrevemos um paciente que desenvolveu trombose de veia poplítea direita durante internação para tratamento de febre por infecção por vírus chicungunha e poliartralgia severa. PMID:29930626

Association between diabetes mellitus, hypothyroidism or hyperadrenocorticism, and atherosclerosis in dogs.

PubMed

Hess, Rebecka S; Kass, Philip H; Van Winkle, Thomas J

2003-01-01

The objective of this study was to determine whether dogs with atherosclerosis are more likely to have concurrent diabetes mellitus, hypothyroidism, or hyperadrenocorticism than dogs that do not have atherosclerosis. A retrospective mortality prevalence case-control study was performed. The study group included 30 dogs with histopathological evidence of atherosclerosis. The control group included 142 dogs with results of a complete postmortem examination, a final postmortem examination diagnosis of neoplasia, and no histopathological evidence of atherosclerosis. Control dogs were frequency matched for age and year in which the postmortem examination was performed. Proportionate changes in the prevalence of diabetes mellitus, hypothyroidism, and hyperadrenocorticism were calculated by exact prevalence odds ratios (POR), 95% confidence intervals (95% CI), and P values. Multiple logistic regression analysis was used to examine the combined effects of prevalence determinants while controlling for age and year of postmortem examination. Dogs with atherosclerosis were over 53 times more likely to have concurrent diabetes mellitus than dogs without atherosclerosis (POR = 53.6; 95% CI, 4.6-627.5; P = .002) and over 51 times more likely to have concurrent hypothyroidism than dogs without atherosclerosis (POR = 51.1; 95% CI, 14.5-180.1; P < .001). Dogs with atherosclerosis were not found to be more likely to have concurrent hyperadrenocorticism than dogs that did not have atherosclerosis (POR = 1.8; 95% CI, 0.2-17.6; P = .59). Diabetes mellitus and hypothyroidism, but not hyperadrenocorticism, are more prevalent in dogs with atherosclerosis compared to dogs without atherosclerosis on postmortem examination.

Neurobiología del autismo y TDAH mediante técnicas de neuroimagen: divergencias y convergencias

PubMed Central

Proal, Erika; Olvera, Jorge González; Blancas, Aurea S.; Chalita, Pablo J.; Castellanos, F. Xavier

2013-01-01

En el área clínica algunos síntomas del trastorno por déficit de atención e hiperactividad (TDAH), se presentan en los pacientes con trastorno del espectro autista (TEA). Se ha demostrado que existen alteraciones en circuitos cerebrales que impactan en fallas cognitivas y de comportamiento específicas de cada uno de estos trastornos. Sin embargo, han sido poco estudiados los correlatos cerebrales que hay detrás tanto de las similitudes como de las diferencias sintomatológicas. En la presente revisión se analizaron los estudios meta-analíticos existentes estructurales y funcionales en TDAH y TEA. Por un lado, se observaron convergencias en circuitos como el dorsal atencional, de funciones ejecutivas, visual, somatomotor y circuito de activación por defecto. Estas similitudes posiblemente explican las manifestaciones comórbidas entre los trastornos como la falla en la integración de información, motricidad fina y procesos atencionales específicos. Por otro lado, específicamente en el TDAH se observan déficits en el circuito de recompensa y ventral atencional, sistemas involucrados en la medición de efectos de reforzamiento y monitoreo atencional. En TEA los circuitos más afectados fueron los implicados en procesos de cognición social y lenguaje. En conclusión, existen correlatos neuronales en TEA que explican las manifestaciones clínicas tanto convergentes como divergentes presentes en TDAH. PMID:23897144

PubMed

Rivera, Souhail Malavé; Díaz, Nelson Varas

2006-01-01

Las profesiones de la salud tienen un papel social dual. Por un lado, velan por el mantenimiento de la salud de la población protegiendo el bien común. Por el otro, dictaminan las formas saludables, y por lo tanto socialmente apropiadas, de ser, actuar y pensar. Este último papel, está más ligado al control social de la población que a una preocupación altruista hacia la misma. A través de esta supervisión y control, se construyen los sujetos a los cuales todos/as debemos aspirar a ser para gozar de aceptación social. Los/as profesionales de la salud han jugado un rol protagónico en dicho proceso, siendo los agentes que delimitan y definen lo que es enfermo vs. saludable, útil vs. inútil, apropiado vs. inapropiado. En el caso de la epidemia del VIH, este esfuerzo se ha hecho cada vez más vigente ya que estos/as profesionales juegan un papel importante en el tratamiento de las personas que viven con VIH/SIDA (PVVS). Sin embargo, su función está plasmada de definiciones que sirven para criminalizar a las PVVS. El objetivo de este estudio fue explorar la manera en que una muestra de profesionales de la salud en Puerto Rico construyen a las PVVS. Con este propósito, entrevistamos 80 profesionales de la salud y estudiantes de estas profesiones. Estas entrevistas fueron grabadas, transcritas y sometidas a un análisis de discurso. Los resultados reflejaron que según las personas participantes: 1) la PVVS no es una persona "normal" o funcional bajo los estándares sociales debido a que su salud no se los permite, 2) representa una carga para la sociedad incluyendo familiares, amigos/as, el mundo del trabajo, e incluso para el gobierno, 3) debe ser vigilada porque representa un riesgo para la persona seronegativa que es descrita como saludable y productiva, y 4) necesita que su salud y conducta sexual sean controladas por vía legal y/o por las personas que representan las instituciones sociales, como lo son los/as profesionales de la salud. En este artículo abordamos el potencial rol de la psicología para servir como vehículo de reconstrucción de dichas nociones, tomando en consideración su propio rol en la formación y mantenimiento de dicho sujeto socialmente deseable.

Queda dos homicídios em São Paulo, Brasil: uma análise descritiva

PubMed Central

Peres, Maria Fernanda Tourinho; Vicentin, Diego; Nery, Marcelo Batista; de Lima, Renato Sérgio; de Souza, Edinilsa Ramos; Cerda, Magdalena; Cardia, Nancy; Adorno, e Sérgio

2012-01-01

Objetivo Descrever a evolução da mortalidade por homicídios no Município de São Paulo segundo tipo de arma, sexo, raça ou cor, idade e áreas de exclusão/inclusão social entre 1996 e 2008. Métodos Estudo ecológico de série temporal. Os dados sobre óbitos ocorridos no Município foram coletados da base de dados do Programa de Aprimoramento das Informações sobre Mortalidade, seguindo a Classificação Internacional de Doenças, Décima Revisão (CID-10). Foram calculadas as taxas de mortalidade por homicídio (TMH) para a população total, por sexo, raça ou cor, faixa etária, tipo de arma e área de exclusão/inclusão social. As TMH foram padronizadas por idade pelo método direto. Foram calculados os percentuais de variação no período estudado. Para as áreas de exclusão/inclusão social foram calculados os riscos relativos de morte por homicídio. Resultados As TMH apresentaram queda de 73,7% entre 2001 e 2008. Foi observada redução da TMH em todos os grupos analisados, mais pronunciada em homens (−74,5%), jovens de 15 a 24 anos (−78,0%) e moradores de áreas de exclusão social extrema (−79,3%). A redução ocorreu, sobretudo, nos homicídios cometidos com armas de fogo (−74,1%). O risco relativo de morte por homicídio nas áreas de exclusão extrema (tendo como referência áreas com algum grau de exclusão social) foi de 2,77 em 1996, 3,9 em 2001 e 2,13 em 2008. Nas áreas de alta exclusão social, o risco relativo foi de 2,07 em 1996 e 1,96 em 2008. Conclusões Para compreender a redução dos homicídios no Município, é importante considerar macrodeterminantes que atingem todo o Município e todos os subgrupos populacionais e microdeterminantes que atuam localmente, influenciando de forma diferenciada os homicídios com armas de fogo e os homicídios na população jovem, no sexo masculino e em residentes em áreas de alta exclusão social. PMID:21390415

The Nursing Diagnosis of risk for pressure ulcer: content validation.

PubMed

Santos, Cássia Teixeira Dos; Almeida, Miriam de Abreu; Lucena, Amália de Fátima

2016-06-14

to validate the content of the new nursing diagnosis, termed risk for pressure ulcer. the content validation with a sample made up of 24 nurses who were specialists in skin care from six different hospitals in the South and Southeast of Brazil. Data collection took place electronically, through an instrument constructed using the SurveyMonkey program, containing a title, definition, and 19 risk factors for the nursing diagnosis. The data were analyzed using Fehring's method and descriptive statistics. The project was approved by a Research Ethics Committee. title, definition and seven risk factors were validated as "very important": physical immobilization, pressure, surface friction, shearing forces, skin moisture, alteration in sensation and malnutrition. Among the other risk factors, 11 were validated as "important": dehydration, obesity, anemia, decrease in serum albumin level, prematurity, aging, smoking, edema, impaired circulation, and decrease in oxygenation and in tissue perfusion. The risk factor of hyperthermia was discarded. the content validation of these components of the nursing diagnosis corroborated the importance of the same, being able to facilitate the nurse's clinical reasoning and guiding clinical practice in the preventive care for pressure ulcers. validar o conteúdo do novo diagnóstico de enfermagem, denominado risco de úlcera por pressão. trata-se de uma validação de conteúdo, com amostra composta por 24 enfermeiros especialistas no cuidado à pele, procedentes de seis diferentes hospitais do Sul e Sudeste brasileiro. A coleta de dados ocorreu por meio eletrônico, em instrumento construído pelo programa SurveyMonkey, que continha título, definição e 19 fatores de risco para o diagnóstico de enfermagem. Os dados foram analisados pelo método de Fehring e pela estatística descritiva. O projeto foi aprovado em Comitê de Ética em Pesquisa. título, definição e sete fatores de risco foram validados como "muito importante", sendo: imobilidade, pressão, fricção, cisalhamento, umidade, sensações prejudicadas e desnutrição. Dentre os demais fatores de risco, onze foram validados como "importante": desidratação, obesidade, anemia, baixo nível de albumina, prematuridade, envelhecimento, tabagismo, edema, circulação prejudicada, diminuição da oxigenação e da perfusão tissular. O fator de risco hipertermia foi descartado. a validação de conteúdo desses componentes do diagnóstico de enfermagem corroborou a importância dos mesmos, podendo facilitar o raciocínio clínico do enfermeiro, norteando a prática clínica no cuidado preventivo à úlcera por pressão. validar el contenido del nuevo diagnóstico de enfermería denominado riesgo de úlcera por presión. se trata de una validación de contenido, con muestra compuesta por 24 enfermeros especialistas en el cuidado de la piel, procedentes de seis diferentes hospitales del Sur y Sureste brasileño. La recolección de datos se realizó por medio electrónico, con un instrumento construido por el programa SurveyMonkey, que contenía: título, definición y 19 factores de riesgo para el diagnóstico de enfermería. Los datos fueron analizados por el método de Fehring y con la estadística descriptiva. El proyecto fue aprobado en el Comité de Ética en Investigación. título, definición y siete factores de riesgo fueron validados como "muy importante"; los factores fueron: inmovilidad, presión, fricción, cizallamiento, humedad, sensaciones perjudicadas y desnutrición. Entre los demás factores de riesgo, once fueron validados como "importante": deshidratación, obesidad, anemia, bajo nivel de albumina sérica, prematuridad, envejecimiento, tabaquismo, edema, circulación perjudicada, disminución de la oxigenación y perfusión tisular. El factor de riesgo hipertermia fue descartado. la validación de contenido, de esos componentes del diagnóstico de enfermería, confirmó la importancia de los mismos, lo que puede facilitar el raciocinio clínico del enfermero, orientando la práctica clínica en el cuidado preventivo de la úlcera por presión.

Assessment of Management to Mitigate Anthropogenic Effects on Large Whales

PubMed Central

Van Der Hoop, Julie M; Moore, Michael J; Barco, Susan G; Cole, Timothy VN; Daoust, Pierre-Yves; Henry, Allison G; McAlpine, Donald F; McLellan, William A; Wimmer, Tonya; Solow, Andrew R

2013-01-01

Abstract United States and Canadian governments have responded to legal requirements to reduce human-induced whale mortality via vessel strikes and entanglement in fishing gear by implementing a suite of regulatory actions. We analyzed the spatial and temporal patterns of mortality of large whales in the Northwest Atlantic (23.5°N to 48.0°N), 1970 through 2009, in the context of management changes. We used a multinomial logistic model fitted by maximum likelihood to detect trends in cause-specific mortalities with time. We compared the number of human-caused mortalities with U.S. federally established levels of potential biological removal (i.e., species-specific sustainable human-caused mortality). From 1970 through 2009, 1762 mortalities (all known) and serious injuries (likely fatal) involved 8 species of large whales. We determined cause of death for 43% of all mortalities; of those, 67% (502) resulted from human interactions. Entanglement in fishing gear was the primary cause of death across all species (n = 323), followed by natural causes (n = 248) and vessel strikes (n = 171). Established sustainable levels of mortality were consistently exceeded in 2 species by up to 650%. Probabilities of entanglement and vessel-strike mortality increased significantly from 1990 through 2009. There was no significant change in the local intensity of all or vessel-strike mortalities before and after 2003, the year after which numerous mitigation efforts were enacted. So far, regulatory efforts have not reduced the lethal effects of human activities to large whales on a population-range basis, although we do not exclude the possibility of success of targeted measures for specific local habitats that were not within the resolution of our analyses. It is unclear how shortfalls in management design or compliance relate to our findings. Analyses such as the one we conducted are crucial in critically evaluating wildlife-management decisions. The results of these analyses can provide managers with direction for modifying regulated measures and can be applied globally to mortality-driven conservation issues. Evaluación del Manejo para Mitigar Efectos Antropogénicos sobre Ballenas Mayores Resumen Los gobiernos de Estados Unidos y Canadá han respondido a requerimientos legales para reducir la mortalidad de ballenas inducida por humanos por medio de impacto con embarcaciones y enmarañamiento en artes de pesca mediante la implementación de un conjunto de acciones reguladoras. Analizamos los patrones espaciales y temporales de la mortalidad de ballenas mayores en el Atlántico Noroccidental (23.5°N a 48.0°N), de 1970 a 2009, en el contexto de cambios de manejo. Utilizamos un modelo logístico multinomial ajustado por la máxima probabilidad de detección de tendencias en mortalidades por causa específica en el tiempo. Comparamos el número de muertes provocadas por humanos con los niveles de remoción biológica potencial (i.e., mortalidad específica provocada por humanos sustentable). De 1970 a 2009, hubo 1762 muertes (conocidas) y lesiones serias (casi fatales) involucrando 8 especies de ballenas mayores. Determinamos la causa de 43% de todas las muertes; de ellas, 67% (502) resultaron de interacciones humanas. El enmarañamiento en artes de pesca fue la causa principal de muerte en todas las especies (n = 323), seguida de causas naturales (n = 248) e impacto de embarcaciones (n = 171). Los niveles sustentables de mortalidad establecidos fueron excedidos consistentemente hasta en 650% en 2 especies. Las probabilidades de muerte por enmarañamiento y por impacto de embarcaciones incrementaron significativamente de 1990 a 2009. No hubo cambio significativo en la intensidad local de mortalidad por todas las causas o por impacto de embarcaciones antes y después de 2003, año en el que se implementaron numerosos esfuerzos de mitigación. Hasta ahora, los esfuerzos regulatorios no han reducido los efectos letales de las actividades humanas sobre las ballenas a nivel de población, aunque no excluimos la posibilidad de éxito de medidas enfocadas a hábitats locales específicos que no estuvieron dentro de la resolución de nuestro análisis. No es claro como se relacionan con nuestros resultados las deficiencias en el diseño o implementación del manejo. Análisis como el que realizamos son cruciales para la evaluación crítica de decisiones para el manejo de vida silvestre, y los resultados de estos análisis pueden proporcionar directrices a los manejadores para que modifiquen medidas regulatorias y puedan ser aplicadas globalmente en temas de conservación relacionadas con mortalidad. PMID:23025354

Strategic Insights, Volume 5, Issue 2, February 2006. Uribe’s Second Mandate, the War, and the Implications for Civil-Military Relations in Colombia

DTIC Science & Technology

2006-02-01

6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS( ES ) Naval Postgraduate...ADDRESS( ES ) 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION/AVAILABILITY STATEMENT Approved for public release...19. “Las FARC – Repliegue por ‘ estrategia ’, o por necesidad,” Centro de Analisis Socilpolitico, June 3, 2005; and “Situación de los terroristas

Assessing the Potential for Interstate Conflict Between Chile and Peru: A Political Economy Approach

DTIC Science & Technology

2009-03-01

Militares Peru-Chile no Se Han Afectado por Diferendo,” El Comercio , April 6, 2008. 329 Chile/Peru: Tensions Flare on Maritime Border Change.” 330 “FF...Relaciones Militares Peru-Chile no Se Han Afectado por Diferendo.” El Comercio , April 6, 2008. “Relations Falter for Peru, Chile.” Chicago Tribune...América Latina y el Mediterráneo (Centro de Estudios e Investigaciones Militares: Santiago, 2000), 82. 129 “A. P. Bureau Chief in Peru is Ordered out of

Unusual Bloom of Tetraselmis sp. in the Valparaiso Bay, Chile

DTIC Science & Technology

2012-01-01

Universidad Técnica Federico Santa María, Sede Viña del Mar, Chile (33º02`05.50``S; 71º35`44.54``O). Los datos de magnitud – dirección del viento por la...λ (nm) 372 Gayana Bot. 69(2), 2012 AGRADECIMIENTOS A Gloria Collantes por identificación del género Tetraselmis. Universidad Técnica Federico Santa...Tetraselmis sp. pudo ser el factor excluyente de las especies de diatomeas, permitiendo alcanzar una alta densidad celular, debido al rápido consumo

[Medical movement in Mexico. To 50 years. Open file].

PubMed

Sandoval-Gutiérrez, José Luis

2017-01-01

Gutiérrez-Samperio hace una excelente narrativa del movimiento denominado «blanco» hace medio siglo, encabezado por médicos y otros trabajadores de salud, principalmente enfermeras. Es importante revisar los logros y limitaciones que dicho fenómeno alcanzó. Por ejemplo, actualmente el residente que cursa una especialidad cuenta con un reconocimiento institucional, universitario y de profesiones al término de su formación, además de tener una beca económica (probablemente insuficiente) y días de vacaciones programados.

OPERATION DOMINIC. FISH BOWL SERIES. Project Officer’s Report. Project 8A.3. Close-In Thermal and X-Ray Vulnerability Measurements--Shots Blue Gill and King Fish

DTIC Science & Technology

1985-09-01

QDC hLt umi ^ POR.2037 (WT-2037)(EX) VOLUME 1 EXTRACTED VERSION OPERATION DOMINIC, FISH BOWL SERIES Project Officer’s Report—Project 8A.3...Close-In Thermal and X-ray Vulnerability Measurements—Shots Blue Gill and King Fish F. D. Adams, Project Officer Flight Dynamics Laboratory Wright...version of POR-2037 (WT-2037), Volume 1, OPERATION DOMINIC; Fish Bowl Series, Project 8A. 3. Approved for public release; distribution is unlimited

Evaluation of the educational technology "Caring for dependent people" by family caregivers in changes and transfers of patients and tube feeding.

PubMed

Landeiro, Maria José Lumini; Peres, Heloísa Helena Ciqueto; Martins, Teresa Vieira

2016-08-18

to assess the contributions of interactive educational technology "Caring for Dependent People" in the development of knowledge to family caregivers of dependent people in a household context and their satisfaction in its use. quasi-experimental study, not randomized, of the before and after type, with a convenience sample of 65 family caregivers, from two Medicine services of a hospital in Porto, Portugal. The Control Group consisted of 33 family caregivers and the Experimental Group of 32, identified by consecutive sampling. The experimental group had access to educational technology at home. Data were collected by socio-demographic, satisfaction and evaluation of knowledge questionnaire, about how to feed by nasogastric tube, positioning and transferring the dependent person. The assessment in both groups had two moments: initial, during hospitalization and one month after discharge. the experimental group had a larger increase in knowledge related to the use of the educational technology. In the control group the knowledge did not differ in the two evaluation time points. these results confirm the improvement of interactive educational technologies and in the training of family caregivers to care for dependents. This technology successfully met the technical quality and learning needs of caregivers, and was considered easy and stimulating. avaliar os contributos da tecnologia educacional interativa "Cuidar de Pessoas Dependentes" no desenvolvimento de conhecimentos aos familiares cuidadores de pessoas dependentes, no contexto domiciliário e a satisfação no seu uso. estudo quasi-experimental, não randomizado, do tipo antes e depois, com amostra de conveniência constituída por 65 familiares cuidadores, de dois Serviços de Medicina de um hospital do Porto, Portugal. O Grupo Controle foi constituído por 33 familiares cuidadores e o Grupo Experimental por 32, identificados por amostragem consecutiva. O grupo experimental teve Acesso à tecnologia educacional no domicílio. Os dados foram colhidos por questionário sociodemográfico de satisfação e avaliação de conhecimentos sobre como alimentar por sonda nasogástrica, posicionar e transferir a pessoa dependente. A avaliação nos dois grupos teve dois momentos: inicial, no internamento e um mês após alta hospitalar. registou-se no grupo experimental um ganho maior de conhecimentos relacionado com a utilização da tecnologia educacional. No grupo controle os conhecimentos não variaram nos dois momentos de avaliação. esses resultados corroboraram na melhoria das tecnologias educacionais interativas e na capacitação dos familiares cuidadores para cuidar de pessoas dependentes. Essa tecnologia atendeu satisfatoriamente as necessidades de qualidade técnica e de aprendizagem dos cuidadores, sendo considerada fácil e estimulante. evaluar las contribuciones de la tecnología educativa interactiva "Cuidar de personas dependientes" en el desarrollo de conocimiento de los familiares cuidadores de personas dependientes en el contexto domiciliario y la satisfacción en su uso. estudio cuasi-experimental, no aleatorizado, de tipo antes-después, con una muestra de 65 familiares cuidadores, de dos servicios de Medicina de un hospital en Oporto, Portugal. El grupo control consistió en 33 familiares cuidadores y el grupo experimental en 32, identificados por muestreo consecutivo. El grupo experimental tuvo acceso a la tecnología de la educación en el hogar. Los datos fueron recolectados por cuestionario sociodemográfico de satisfacción y evaluación de los conocimientos sobre cómo alimentar por sonda nasogástrica, posicionar y transferir a la persona dependiente. La evaluación en ambos grupos tuvo dos etapas: inicial, durante la hospitalización y un mes después del alta. se registraron en el grupo experimental aumentos del conocimiento relacionado con el uso de la tecnología educativa. En el grupo control el conocimiento no difirió en los dos puntos en el tiempo. estos resultados confirmaron el beneficio de las tecnologías interactivas educativas y la formación de los familiares cuidadores para el cuidado de personas dependientes. Esta tecnología cumplió con éxito con las necesidades técnicas y de calidad de aprendizaje de los cuidadores, siendo considerada fácil y estimulante.

Nursing care missed in patients at risk of or having pressure ulcers.

PubMed

Valles, Jonathan Hermayn Hernández; Monsiváis, María Guadalupe Moreno; Guzmán, Ma Guadalupe Interial; Arreola, Leticia Vázquez

2016-11-21

to determine the nursing care missed as perceived by the nursing staff and its relation with the nursing care missed identified in the assessment of patients at risk of or having pressur ulcers. descriptive correlation study. The participants were 161 nurses and 483 patients from a public hospital. The MISSCARE survey was used in combination with a Nursing Care Assessment Form for Patients at Risk of or having pressure ulcers. For the analysis, descriptive and inferential statistics were used. the nursing staff indicated greater omission in skin care (38.5%), position change (31.1%) and the registration of risk factors for the development of pressure ulcers (33.5%). The nursing care missed identified in the assessment related to the use of pressure relief on bony prominences and drainage tubes interfering in the patient's movements (both with 58.6%) and the use of pneumatic mattresses (57.6%). a high percentage of nursing care missed was found according to the staff's perception. Nevertheless, the assessment of the nursing care missed was much higher. No significant relation was found between both. Therefore, it is a priority to reflect on the importance of objective patient assessments. determinar o cuidado de enfermagem omitido percebido pela equipe de enfermagem e sua relação com o cuidado omitido identificado na avaliação de pacientes com risco ou com de úlceras por pressão. estudo descritivo correlacional. Participaram 161 enfermeiras e 483 pacientes de um hospital público. Foram utilizados o levantamento MISSCARE e um Formulário de Avaliação de Cuidados de Enfermagem em Pacientes com Risco ou com úlceras por pressão. Para a análise foi utilizada estatística descritiva e inferencial. a equipe de enfermagem assinalou que há maior omissão no cuidado da pele (38,5%), reposicionamento (31,1%) e no registro de fatores de risco para o aparecimento de úlceras por pressão (33,5%). Os cuidados de enfermagem omitidos identificados na avaliação foram o uso de redutor de pressão em proeminências ósseas e tubos de drenagem que interferem nos movimentos do paciente (ambos com 58,6%) e uso de colchões pneumáticos (57,6%). foi encontrada alta porcentagem de cuidado de enfermagem omitido na percepção da equipe. Porém, a avaliação do cuidado omitido foi muito superior. Não foi encontrada associação significativa entre ambos, priorizando reflexões sobre a importância de avaliações objetivas dos pacientes. determinar el cuidado de enfermería perdido percibido por el personal de enfermería y su relación con el cuidado perdido identificado en la valoración de pacientes con riesgo o con presencia de úlceras por presión. estudio descriptivo correlacional. Participaron 161 enfermeras y 483 pacientes de un hospital público. Se utilizó la encuesta MISSCARE y una Cédula de Valoración de Cuidados de Enfermería en Pacientes con Riesgo o con úlceras por presión. Para el análisis se utilizó estadística descriptiva e inferencial. el personal de enfermería señaló que existe mayor omisión en el cuidado de la piel (38.5%), cambio de posición (31.1%) y en el registro de factores de riesgo para la aparición de úlceras por presión (33.5%). Los cuidados de enfermería perdidos identificados en la valoración fueron uso de liberador de presión en prominencias óseas y tubos de drenaje que interfieren en movimientos del paciente (ambos con 58.6%) y uso de colchones neumáticos (57.6%). se encontró un alto porcentaje de cuidado de enfermería perdido de acuerdo a la percepción del personal, sin embargo, el cuidado perdido valorado fue mucho mayor. No se encontró relación significativa entre ambos por lo que es prioritario reflexionar acerca de la importancia de realizar valoraciones objetivas en los pacientes.

Detección y estudio mediante Fluorescencia Inducida por Láser de radicales libres formados por Disociación Multifotónica Infrarroja

NASA Astrophysics Data System (ADS)

Santos, M.; Díaz, L.; Torresano, J. A.; Rubio, L.; Samoudi, B.

Una de las principales aplicaciones actuales de los procesos de disociación multifotónica inducidos por radiación láser infrarroja (DMI) es la producción de radiales libres, con el fin de estudiar sus propiedades cinéticas y espectroscópicas. La disociación de moléculas poliatómicas en el IR con láseres de CO2 tiene lugar desde la superficie de energía molecular mas baja y conduce generalmente a la formación de fragmentos en el estado electrónico fundamental, con diversos grados de excitación vibracional. En el Grupo de Procesos Multifotónicos del Instituto de Estructura de la Materia del C.S.I.C. hemos puesto a punto la técnica de Fluorescencia Inducida por Láser (LIF) para la detección y análisis en tiempo real de los fragmentos producidos en la DMI inducida mediante uno o dos campos láseres de diferentes longitudes de onda. Objetivos de nuestro trabajo han sido el estudio de los canales de disociación mayoritarios y de las especies transitoria producidas, así como de la distribución de energía interna con que éstas son generadas. En particular hemos detectado mediante LIF las especies: C2, CF, CH, SiH2, CF2, CH2, SiHCl, y CF3 a partir de la disociación de, entre otras, las siguientes moléculas: C2H3Br, C3F6, C4H8Si, C2H5ClSi y CH5ClSi. En este trabajo presentamos algunos de los resultados obtenidos mediante el estudio por LIF de estos radicales: estudio temporal de la señal LIF obtenida con determinación de tiempos de vida, espectros de excitación y fluorescencia, temperaturas vibracionales de formación, variación de la intensidad LIF con el tiempo de retraso entre los láseres de disociación y prueba, etc.

Protection by meningococcal outer membrane protein PorA-specific antibodies and a serogroup B capsular polysaccharide-specific antibody in complement-sufficient and C6-deficient infant rats.

PubMed

Toropainen, Maija; Saarinen, Leena; Vidarsson, Gestur; Käyhty, Helena

2006-05-01

The relative contributions of antibody-induced complement-mediated bacterial lysis and antibody/complement-mediated phagocytosis to host immunity against meningococcal infections are currently unclear. Further, the in vivo effector functions of antibodies may vary depending on their specificity and Fc heavy-chain isotype. In this study, a mouse immunoglobulin G2a (mIgG2a) monoclonal antibody (MN12H2) to meningococcal outer membrane protein PorA (P1.16), its human IgG subclass derivatives (hIgG1 to hIgG4), and an mIgG2a monoclonal antibody (Nmb735) to serogroup B capsular polysaccharide (B-PS) were evaluated for passive protection against meningococcal serogroup B strain 44/76-SL (B:15:P1.7,16) in an infant rat infection model. Complement component C6-deficient (PVG/c-) rats were used to assess the importance of complement-mediated bacterial lysis for protection. The PorA-specific parental mIgG2a and the hIgG1 to hIgG3 derivatives all induced efficient bactericidal activity in vitro in the presence of human or infant rat complement and augmented bacterial clearance in complement-sufficient HsdBrlHan:WIST rats, while the hIgG4 was unable to do so. In C6-deficient PVG/c- rats, lacking complement-mediated bacterial lysis, the augmentation of bacterial clearance by PorA-specific mIgG2a and hIgG1 antibodies was impaired compared to that in the syngeneic complement-sufficient PVG/c+ rat strain. This was in contrast to the case for B-PS-specific mIgG2a, which conferred similar protective activity in both rat strains. These data suggest that while anti-B-PS antibody can provide protection in the infant rats without membrane attack complex formation, the protection afforded by anti-PorA antibody is more dependent on the activation of the whole complement pathway and subsequent bacterial lysis.

Resistance of the peripheral nervous system to the effects of chronic canine hypothyroidism.

PubMed

Rossmeisl, J H

2010-01-01

Hypothyroidism has been implicated in the development of multiple peripheral mono- and polyneuropathies in dogs. The objectives of this study were to evaluate the clinical and electrophysiologic effects of experimentally induced hypothyroidism on the peripheral nervous system of dogs. Chronic hypothyroidism will induce peripheral nerve sensorimotor dysfunction. Eighteen purpose-bred, female dogs. Prospective, longitudinal study: Hypothyroidism was induced by radioactive iodine administration in 9 dogs, and the remaining 9 served as untreated controls. Neurological examinations were performed monthly. Electrophysiologic testing consisting of electromyography (EMG); motor nerve conduction studies of the sciatic-tibial, radial, ulnar, and recurrent laryngeal nerves; sciatic-tibial and ulnar F-wave studies; sensory nerve conduction studies of the tibial, ulnar, and radial nerves; and evaluation of blink reflex and facial responses were performed before and 6, 12, and 18 months after induction of hypothyroidism and compared with controls. Clinical evidence of peripheral nervous dysfunction did not occur in any dog. At 6 month and subsequent evaluations, all hypothyroid dogs had EMG and histologic evidence of hypothyroid myopathy. Hypothyroid dogs had significant (Por=.1) or sensory nerve conduction velocity (P>or=.24) or nerve roots (P>or=.16) throughout the study period, with values remaining within reference ranges in all dogs. Chronic hypothyroidism induced by thyroid irradiation does not result in clinical or electrophysiologic evidence of peripheral neuropathy, but does cause subclinical myopathy.

PubMed

Espuig Sebastián, Rosana; Noreña Peña, Ana Lucía; Cortés Castel, Ernesto; González-San, Juan de Diego

2016-09-20

Introducción: el estado nutricional previo de la embarazada, la adecuada ganancia de peso y la ingesta de ciertos nutrientes pueden tener una influencia importante tanto para la madre como para el recién nacido, a corto y largo plazo. Las recomendaciones de la Organización Mundial de la Salud son transmitidas durante el control del embarazo por la matrona.Objetivos: analizar los principales estudios sobre la percepción de las embarazadas acerca de los consejos nutricionales recibidos e identificar las estrategias utilizadas por las matronas para su implementación.Metodología: búsqueda bibliográfica sobre embarazadas de bajo riesgo controladas por matronas y que reciben consejos nutricionales realizada en WOS, CINHAL y PubMed. Se utilizaron los descriptores: pregnancy, pregnant, midwife, counselling, nutritiony sus diferentes combinaciones. Los criterios de inclusión fueron artículos originales y revisiones en inglés, español o portugués de los últimos diez años y disponibles en texto completo.Resultados: se encontraron 184 referencias. Solo 11 tratan el tema abordado. Existen múltiples artículos con consejos nutricionales en el embarazo, pero muy pocos que incluyan estrategias educativas implementadas por las matronas que aborden recomendaciones dietético-nutricionales y su utilidad.Conclusión: existen escasos estudios que investiguen los conocimientos que las matronas tienen sobre nutrición en el embarazo y los consejos que aportan sobre el tema. Igualmente sucede con los trabajos que estudian la percepción que tienen las gestantes sobre los consejos nutricionales recibidos.

Geochemical analyses reveal the importance of environmental history for blue carbon sequestration

NASA Astrophysics Data System (ADS)

Kelleway, J. J.; Saintilan, N.; Macreadie, P. I.; Baldock, J. A.; Heijnis, H.; Zawadzki, A.; Gadd, P.; Jacobsen, G.; Ralph, P. J.

2017-07-01

Coastal habitats including saltmarshes and mangrove forests can accumulate and store significant blue carbon stocks, which may persist for millennia. Despite this implied stability, the distribution and structure of intertidal-supratidal wetlands are known to respond to changes imposed by geomorphic evolution, climatic, sea level, and anthropogenic influences. In this study, we reconstruct environmental histories and biogeochemical conditions in four wetlands of similar contemporary vegetation in SE Australia. The objective is to assess the importance of historic factors to contemporary organic carbon (C) stocks and accumulation rates. Results from the four cores—two collected from marine-influenced saltmarshes (Wapengo marine site (WAP-M) and Port Stephens marine site (POR-M)) and two from fluvial influenced saltmarshes (Wapengo fluvial site (WAP-F) and Port Stephens fluvial site (POR-F))—highlight different environmental histories and preservation conditions. High C stocks are associated with the presence of a mangrove phase below the contemporary saltmarsh sediments in the POR-M and POR-F cores. 13C nuclear magnetic resonance analyses show this historic mangrove root C to be remarkably stable in its molecular composition despite its age, consistent with its position in deep sediments. WAP-M and WAP-F cores did not contain mangrove root C; however, significant preservation of char C (up to 46% of C in some depths) in WAP-F reveals the importance of historic catchment processes to this site. Together, these results highlight the importance of integrating historic ecosystem and catchment factors into attempts to upscale C accounting to broader spatial scales.

Subjeans Condensations due to a Thermal Instability

NASA Astrophysics Data System (ADS)

Opher, R.; Valio, A.

1990-11-01

RESUMEN. Las observaciones recientes muestran que las nubes moleculares no son homogeneas, sino que tienen condensaciones. Se observa que estas condensaciones estan libres gravitacionalmente. C6mo se forman estas condensaciones? Sugerimos explicar estas conden sac jones como debidas a que la inestabilidad termica ayuda a la gravedad. Se estudi6 una funci5n de enfriamiento por gramo de la forma general A p T , en donde p y T son la densidad y la temperatura. Estamos interesados en el valor maximo de para la cual el colapso ocurre. Se estudiaron varios mode- los. Nuestros resultados indican que los valores de comparables con aquellos sugeridos por la literatura (1 < son suficientes para provocar el colapso de masas inferiores a la masa de Jeans por medio de inestabilidad termica, ayudada por gravedad y asi se forman las condensaciones libres gravitacionalmente. ABSTRACT: Recent observations show that molecular clouds are not homogeneous, but clumpy. Some clumps are observed to be gravitationally unbound. How did these clumps then form? We suggest explaining these condensation as due to thermal instability aiding gravit y The cooling function per gram studied is of the general form A p T,where pand T are the density and temperature, respectively. We are interested in the maximum value of for which collapse still occurs. Various models are studied. Our results indicate that values comparable to those suggested in the literature (1 < %< 2) are sufficient to trigger the collapse of subjeans masses by thermal instability, when aided by gravity, and form the observed gravitationally unbound clumps. Keq o : HYDRODYNAMICS - INTERSTELLAR CLOUDS

The role of appearance investment in the adjustment of women with breast cancer.

PubMed

Moreira, Helena; Silva, Sónia; Canavarro, Maria Cristina

2010-09-01

Appearance investment can be considered an important factor in the explanation of individual differences in adjustment to breast cancer. This study aims to analyze the role of this variable on a set of adjustment outcomes, namely, quality of life (QOL), emotional adjustment (depression and anxiety) and fear of negative evaluations. The differential role of motivational salience facet of appearance investment (MS; the individual's efforts to be or feel attractive), conceptualized as a protective factor, and of self-evaluative salience facet (SES; the importance an individual places on physical appearance for their definition of self-worth), conceptualized as a vulnerability factor, is explored. This cross-sectional study included 117 Portuguese breast cancer patients (mean age=52.47; SD=8.81), on average 2.32 months (SD=2.17) post-diagnosis. Appearance investment was measured by the ASI-R; QOL by the WHOQOL-bref; emotional adjustment by the HADS; and fear of negative evaluations by the FNE (Portuguese versions). Several hierarchical multiple regressions were conducted for each outcome, using investment facets as a predictor variable. Both facets of investment contributed to the explanation of social (p

ROBOTIC ASSISTED SINGLE SITE FOR BILATERAL INGUINAL HERNIA REPAIR.

PubMed

Bosi, Henrique Rasia; Guimarães, José Ricardo; Cavazzola, Leandro Totti

2016-01-01

The inguinal hernia is one of the most frequent surgical diseases, being frequent procedure and surgeon´s everyday practice. To present technical details in making hernioplasty using robotic equipment on bilateral inguinal hernia repair with single port and preliminary results with the method. The bilateral inguinal hernia repair was performed by using the Single-Site(c) Da Vinci Surgical Access Platform to the abdominal cavity and the placement of clamps. This technique proved to be effective for inguinal hernia and have more aesthetic result when compared to other techniques. Inguinal hernia repair robot-assisted with single-trocar is feasible and effective. However, still has higher costs needing surgical team special training. A hérnia inguinal é uma das doenças cirúrgicas mais frequentes, tornando-a procedimento frequente e do cotidiano do cirurgião. Apresentar detalhes da técnica da hernioplastia inguinal bilateral robótica por single-site e resultados preliminares com o método. Foi realizada hernioplastia inguinal bilateral assistida por robô, utilizando-se da Vinci Single-Site(c) Surgical Platform para acesso a cavidade abdominal e colocação das pinças. Esta técnica demonstrou-se efetiva para correção da hérnia inguinal, além de apresentar melhor resultado estético quando comparado às outras técnicas. A hernioplastia inguinal assistida por robô com trocarte único é viável e eficaz. Contudo, ainda apresenta custos mais elevados e necessidade de treinamento especial por parte da equipe cirúrgica.

El espectro de KX TrA entre 1990 y 1996

NASA Astrophysics Data System (ADS)

Brandi, E.; García, L.; Ferrer, O.; Barbá, R.

La estrella simbiótica KX TrA = He2-177 fue observada espectroscópicamente con el telescopio de 2.15 m del CASLEO entre los años 1990 y 1996, utilizándose resoluciones intermedia y alta. El rango espectral estudiado se extiende desde 4400 Åa 7200 Å. La historia fotométrica de KX TrA presenta explosiones del mismo tipo que las mostradas por la nova lenta RR Tel y su espectro de alta excitación, muy rico en líneas de emisión, es también similar al de RR Tel. Por lo tanto, es importante analizar la evolución espectral de KX TrA en el tiempo, prestando especial atención a los posibles cambios en los niveles de excitación. Las emisiones presentes corresponden a transiciones permitidas y prohibidas con un amplio rango de ionización, incluyéndose las anchas e intensas líneas originadas por scattering Raman de O VI en λλ 6825 y 7082 Å. En el período cubierto por nuestras observaciones se estudia la variación de la intensidad relativa de las emisiones, el comportamiento de las velocidades radiales y los cambios de perfiles de las líneas, especialmente en Hα y Hβ. El contínuo de la región roja observada indica un tipo espectral no más tardío que M3 para la componente gigante fría del sistema.

Efficacy and safety of follitropin alfa/lutropin alfa in ART: a randomized controlled trial in poor ovarian responders.

PubMed

Humaidan, P; Chin, W; Rogoff, D; D'Hooghe, T; Longobardi, S; Hubbard, J; Schertz, J

2017-03-01

How does the efficacy and safety of a fixed-ratio combination of recombinant human FSH plus recombinant human LH (follitropin alfa plus lutropin alfa; r-hFSH/r-hLH) compare with that of r-hFSH monotherapy for controlled ovarian stimulation (COS) in patients with poor ovarian response (POR)? The primary and secondary efficacy endpoints were comparable between treatment groups and the safety profile of both treatment regimens was favourable. Although meta-analyses of clinical trials have suggested some beneficial effect on reproductive outcomes with r-hLH supplementation in patients with POR, the definitions of POR were heterogeneous and limit the comparability across studies. Phase III, single-blind, active-comparator, randomized, parallel-group clinical trial. Patients were followed for a single ART cycle. A total of 939 women were randomized (1:1) to receive either r-hFSH/r-hLH or r-hFSH. Randomization, stratified by study site and participant age, was conducted via an interactive voice response system. Women classified as having POR, based on criteria incorporating the ESHRE Bologna criteria, were down-regulated with a long GnRH agonist protocol and following successful down-regulation were randomized (1:1) to COS with r-hFSH/r-hLH or r-hFSH alone. The primary efficacy endpoint was the number of oocytes retrieved following COS. Safety endpoints included the incidence of adverse events, including ovarian hyperstimulation syndrome (OHSS). Post hoc analyses investigated safety outcomes and correlations between live birth and baseline characteristics (age and number of oocytes retrieved in previous ART treatment cycles or serum anti-Müllerian hormone (AMH)). The significance of the treatment effect was tested by generalized linear models (Poisson regression for counts and logistic regression for binary endpoints) adjusting for age and country. Of 949 subjects achieving down-regulation, 939 were randomized to r-hFSH/r-hLH (n = 477) or r-hFSH (n = 462) and received treatment. Efficacy assessment: In the intention-to-treat (ITT) population, the mean (SD) number of oocytes retrieved (primary endpoint) was 3.3 (2.71) in the r-hFSH/r-hLH group compared with 3.6 (2.82) in the r-hFSH group (between-group difference not statistically significant). The observed difference between treatment groups (r-hFSH/r-hLH and r-hFSH, respectively) for efficacy outcomes decreased over the course of pregnancy (biochemical pregnancy rate: 17.3% versus 23.9%; clinical pregnancy rate: 14.1% versus 16.8%; ongoing pregnancy rate: 11.0% versus 12.4%; and live birth rate: 10.6% versus 11.7%). An interaction (identified post hoc) between baseline characteristics related to POR and treatment effect was noted for live birth, with r-hFSH/r-hLH associated with a higher live birth rate for patients with moderate or severe POR, whereas r-hFSH was associated with a higher live birth rate for those with mild POR. A post hoc logistic regression analysis indicated that the incidence of total pregnancy outcome failure was lower in the r-hFSH/r-hLH group (6.7%) compared with the r-hFSH group (12.4%) with an odds ratio of 0.52 (95% CI 0.33, 0.82; P = 0.005). Safety assessment: The overall proportion of patients with treatment-emergent adverse events (TEAEs) occurring during or after r-hFSH/r-hLH or r-hFSH use (stimulation or post-stimulation phase) was 19.9% and 26.8%, respectively. There was no consistent pattern of TEAEs associated with either treatment. Despite using inclusion criteria for POR incorporating the ESHRE Bologna criteria, further investigation is needed to determine the impact of the heterogeneity of POR in the Bologna patient population. The observed correlation between baseline clinical characteristics related to POR and live birth rate, as well as the observed differences between groups regarding total pregnancy outcome failure were from post hoc analyses, and the study was not powered for these endpoints. In addition, the attrition rate for pregnancy outcomes in this trial may not reflect general medical practice. Furthermore, as the patient population was predominantly White these results might not be applicable to other ethnicities. In the population of women with POR investigated in this study, although the number of oocytes retrieved was similar following stimulation with either a fixed-ratio combination of r-hFSH/r-hLH or r-hFSH monotherapy, post hoc analyses showed that there was a lower rate of total pregnancy outcome failure in patients receiving r-hFSH/r-hLH, in addition to a higher live birth rate in patients with moderate and severe POR. These findings are clinically relevant and require additional investigation. The benefit:risk balance of treatment with either r-hFSH/r-hLH or r-hFSH remains positive. This study was funded by Merck KGaA, Darmstadt, Germany. P.H. has received honoraria for lectures and unrestricted research grants from Ferring, Merck KGaA and MSD. D.R. is a former employee of EMD Serono, a business of Merck KGaA, Darmstadt, Germany. J.S., J.H. and W.C. are employees of EMD Serono Research and Development Institute, a business of Merck KGaA, Darmstadt, Germany. T.D.'H. and S.L. are employees of Merck KGaA, Darmstadt, Germany. ClinicalTrials.gov identifier: NCT02047227; EudraCT Number: 2013-003817-16. ClinicalTrials.gov: 24 January 2014; EudraCT: 19 December 2013. 30 January 2014. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology.

Observaciones de la corona solar interior con un coronógrafo de espejo

NASA Astrophysics Data System (ADS)

Stenborg, G.; Schwenn, R.; Francile, C.; Rovira, M.

El plasma de la corona solar es un buen indicador de las líneas de fuerza del campo magnético. Por lo tanto, el análisis de estructuras coronales cuasiestacionarias en la corona da importante información sobre el campo magnético y la actividad asociada. Se trata de poner límites a los modelos teóricos existentes mediante el estudio de distintas estructuras en la corona interior. En agosto de 1997 comenzó a operar el coronógrafo solar (MICA) en El Leoncito como parte del Observatorio Solar Alemán-Argentino. Desde su instalación obtiene imágenes de la corona solar (1.05 a 2.0 radios solares) en 2 líneas espectrales correspondientes a la emisión de Fe XIV y Fe X. El instrumento puede obtener imágenes cada minuto por lo que es ideal para estudiar procesos rápidos. Presentamos observaciones recientes que muestran la capacidad del coronógrafo así como la evolución de algunos eventos dinámicos observados por MICA.

Proteomic analysis of human follicular fluid in poor ovarian responders during in vitro fertilization.

PubMed

Oh, Jae Won; Kim, Seul Ki; Cho, Kyung-Cho; Kim, Min-Sik; Suh, Chang Suk; Lee, Jung Ryeol; Kim, Kwang Pyo

2017-03-01

Poor ovarian response (POR) in controlled ovarian stimulation is often observed during in vitro fertilization and embryo transfer cycles and it is a major problem. A POR has been found to be related to several factors, including advanced age, high body mass index, and history of ovarian or pelvic surgery. However, it is difficult to predict POR, as there are no specific biomarkers known. In this study, we used quantitative proteomic analyses to investigate potential biomarkers that can predict poor response during in vitro fertilization based on follicular fluid samples. A total of 1079 proteins were identified using a high-resolution orbitrap mass spectrometer coupled online to a nanoflow-LC system. It is notable that 65 upregulated and 66 downregulated proteins were found to be functionally enriched in poor responders. We also validated these differentially expressed proteins using a triple-quadrupole mass spectrometer for quantification of targeted proteins. Of the differentially expressed proteins, three proteins (pregnancy zone protein, renin, and sushi repeat-containing protein SRPX) were regarded as statistically significant (p < 0.05). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

La edad de las familias Eos, Themis y Koronis

NASA Astrophysics Data System (ADS)

Gil-Hutton, R.

Las familias de asteroides son el producto de la disrupción colisional de objetos destruídos por impactos ocurridos en el cinturón principal. Las colisiones posteriores han modificado los tamaños y las órbitas de los miembros de estas familias, por lo que las distribuciones que vemos hoy en día pueden ser muy diferentes de aquellas producidas inmediatamente después de la fragmentación del objeto original. En esta hipótesis, puede ser difícil reconstruir la evolución colisional de la familia basándose sólo en las actuales distribuciones y puede ser necesario hacer ciertas suposiciones para obtener información sobre las condiciones iniciales. En este trabajo se deriva una estimación de la edad de las familias Eos, Themis y Koronis obtenida de una simulación de la evolución colisional de un cuerpo original teórico para cada familia usando un modelo de distribución para el cinturón propuesto por Gil-Hutton (1996).

Trombocitopenia induzida por heparina em paciente com oclusão arterial aguda

PubMed Central

Pimenta, Rafael Elias Farres; Yoshida, Winston Bonetti; Rollo, Hamilton Almeida; Sobreira, Marcone Lima; Bertanha, Matheus; Mariúba, Jamil Victor de Oliveira; Jaldin, Rodrigo Gibin; de Camargo, Paula Angeleli Bueno

2016-01-01

Resumo A trombocitopenia induzida por heparina é uma complicação grave da terapêutica anticoagulante com heparina e está associada à formação de anticorpos antifator IV plaquetário. Costuma surgir a partir do quinto dia do tratamento, com queda de pelo menos 50% da contagem plaquetária. Em decorrência da ativação plaquetária concomitante, pode ocorrer quadro de trombose, venosa ou arterial, com repercussões clínicas graves. Apresentamos um caso de paciente portador de síndrome do anticorpo antifosfolípide, com quadro de oclusão arterial aguda, que foi tratado cirurgicamente e recebeu heparina não fracionada no intra e pós-operatório. No quinto dia de tratamento anticoagulante, apresentou queda maior de 50% da contagem de plaquetas em relação à contagem pré-heparina. A suspeita de trombocitopenia induzida por heparina e seus aspectos diagnósticos e terapêuticos serão abordados neste desafio terapêutico.

Effect of SPM-based cleaning POR on EUV mask performance

NASA Astrophysics Data System (ADS)

Choi, Jaehyuck; Lee, Han-shin; Yoon, Jinsang; Shimomura, Takeya; Friz, Alex; Montgomery, Cecilia; Ma, Andy; Goodwin, Frank; Kang, Daehyuk; Chung, Paul; Shin, Inkyun; Cho, H.

2011-11-01

EUV masks include many different layers of various materials rarely used in optical masks, and each layer of material has a particular role in enhancing the performance of EUV lithography. Therefore, it is crucial to understand how the mask quality and patterning performance can change during mask fabrication, EUV exposure, maintenance cleaning, shipping, or storage. The fact that a pellicle is not used to protect the mask surface in EUV lithography suggests that EUV masks may have to undergo more cleaning cycles during their lifetime. More frequent cleaning, combined with the adoption of new materials for EUV masks, necessitates that mask manufacturers closely examine the performance change of EUV masks during cleaning process. We have investigated EUV mask quality and patterning performance during 30 cycles of Samsung's EUV mask SPM-based cleaning and 20 cycles of SEMATECH ADT exposure. We have observed that the quality and patterning performance of EUV masks does not significantly change during these processes except mask pattern CD change. To resolve this issue, we have developed an acid-free cleaning POR and substantially improved EUV mask film loss compared to the SPM-based cleaning POR.

Diagnostic labels of NANDA-I in a southern region of Spain.

PubMed

González-Rodríguez, Rafael; Martelo-Baro, María de Los Ángeles; Bas-Sarmiento, Pilar

2017-06-08

to determine the incidence of NANDA-I diagnostic labels (North American Nursing Diagnosis Association-International) and to establish the distribution of cases of assistance and the associated labels, according to sociodemographic variables (age and sex). descriptive, cross-sectional epidemiological study of labels of NANDA-I, under ecological design. The distribution of labels was analyzed according to sex and age; the corresponding frequencies were calculated and for each label the incidence were calculated rates with aggregate data from the attended cases. the total number of cases of care under study was 9,928 (41.65% men and 58.35% women). The identified labels were 16,456 (7,084 men and 9,372 women); average of 1.7 labels per case of care; Out of 216 labels proposed by NANDA-I, in its 2012-14 classification, 152 were used, representing 70.4%. The labels with the highest incidence rates per thousand inhabitants were: Anxiety, Willingness to Improve Knowledge and Risk of Infection. the study allowed detecting, through NANDA-I, the answers to the health problems of greater incidence in the users attended. determinar la incidencia de las etiquetas diagnósticas de la NANDA-I (North American Nursing Diagnosis Association-International) y establecer la distribución de los episodios asistenciales y de sus respectivas etiquetas, en función de variables sociodemográficas (edad y sexo). estudio epidemiológico descriptivo y de corte transversal de las etiquetas de la NANDA-I, bajo diseño ecológico. Se analizó la distribución de las etiquetas según sexo y edad, se calcularon las frecuencias correspondientes y se computaron las tasas de incidencia con datos agregados para los episodios asistenciales por etiqueta. el número total de episodios asistenciales del estudio fue de 9.928 (41,65% hombres y 58,35% mujeres). Las etiquetas identificadas en los episodios fueron 16.456 (7.084 hombres y 9.372 mujeres), con un promedio de 1,7 etiquetas por episodio; de las 216 etiquetas propuestas por la NANDA-I, en su clasificación 2012-14, se utilizaron 152, lo que representó 70,4%. Las etiquetas con mayores tasas de incidencia por mil habitantes fueron: Ansiedad, Disposición para mejorar los conocimientos y Riesgo de infección. el estudio permitió detectar, a través de la NANDA-I, las respuestas a los problemas de salud de mayor incidencia en los usuarios atendidos. determinar a incidência das etiquetas diagnósticas da NANDA-I (North American Nursing Diagnosis Association - International) e estabelecer a distribuição dos episódios assistenciais e de suas respectivas etiquetas em função de variáveis sociodemográficas (idade e sexo). estudo epidemiológico descritivo, de corte transversal, das etiquetas da NANDA-I, de desenho ecológico. A distribuição das etiquetas segundo sexo e idade foi analisada; as frequências correspondentes foram calculadas e as taxas de incidência com dados agregados para os episódios assistenciais por etiqueta foram computadas. o número total de episódios assistenciais do estudo foi de 9.928 (41,65% homens e 58,35% mulheres). As etiquetas identificadas nesses episódios foram 16.456 (7.084 de homens e 9.372 de mulheres), com uma média de 1,7 etiquetas por episódio; das 216 etiquetas propostas pela NANDA-I, na sua classificação 2012-14, foram utilizadas 152, o que representou 70,4%. As etiquetas com maiores taxas de incidência por mil habitantes foram: Ansiedade, Disposição para melhorar os conhecimentos e Risco de infecção. o estudo permitiu detectar, por meio da NANDA-I, as respostas aos problemas de saúde de maior incidência nos usuários atendidos.

Pasado, presente y futuro de la epidemiología. Una perspective latinoamericana

PubMed Central

Morabia, Alfredo

2015-01-01

Este artículo intenta contestar tres preguntas. Sobre el pasado: ¿Por qué no existió una epidemiología precolombina? Sobre el presente: ¿Cuáles son los orígenes de la epidemiología moderna, incluyendo sus raíces sudamericanas? Y sobre el futuro, escogí un título surrealista para enfatizar el hecho que estoy consciente de que es siempre delicado hacer predicciones: ¿Por qué fenómenos complejos son los “objetos oscuros del deseo” epidemiológico? PMID:25124247

?Cuales son las amenazas o peligros volcanicos?

USGS Publications Warehouse

Myers, Bobbie; Brantley, Steven R.; Stauffer, Peter; Hendley, James W.

2000-01-01

Los volcanes son capaces de producir numerosos peligros geologicos e hidrologicos. Los cientificos del Servicio Geologico de los EE. UU. (USGS, por sus siglas en ingles) y de otras instituciones alrededor del mundo estan estudiando los peligros de muchos de los centenares de volcanes activos y potencialmente activos del mundo. Estos cientificos vigilan muy de cerca la actividad de algunos de los volcanes mas peligrosos, por lo que estan preparados para alertar a las autoridades y/o a la poblacion en caso de que aumente sustancialmente la probabilidad de que ocurra una erupcion u otro evento peligroso.

Trends in corrected lung cancer mortality rates in Brazil and regions.

PubMed

Malta, Deborah Carvalho; Abreu, Daisy Maria Xavier de; Moura, Lenildo de; Lana, Gustavo C; Azevedo, Gulnar; França, Elisabeth

2016-06-27

To describe the trend in cancer mortality rates in Brazil and regions before and after correction for underreporting of deaths and redistribution of ill-defined and nonspecific causes. The study used data of deaths from lung cancer among the population aged from 30 to 69 years, notified to the Mortality Information System between 1996 and 2011, corrected for underreporting of deaths, non-registered sex and age , and causes with ill-defined or garbage codes according to sex, age, and region. Standardized rates were calculated by age for raw and corrected data. An analysis of time trend in lung cancer mortality was carried out using the regression model with autoregressive errors. Lung cancer in Brazil presented higher rates among men compared to women, and the South region showed the highest death risk in 1996 and 2011. Mortality showed a trend of reduction for males and increase for women. Lung cancer in Brazil presented different distribution patterns according to sex, with higher rates among men and a reduction in the mortality trend for men and increase for women. Descrever a tendência da mortalidade por câncer de pulmão no Brasil e regiões, antes e após as correções por sub-registro de óbitos, redistribuição de causas mal definidas e causas inespecíficas. Foram utilizados dados de óbitos por câncer de pulmão da população de 30 a 69 anos, notificados ao Sistema de Informação sobre Mortalidade, entre 1996 e 2011, corrigidos para sub-registro de óbitos, declaração de sexo e idade ignorados e causas com códigos mal definidos e inespecíficos segundo sexo, idade e região. Foram calculadas taxas padronizadas por idade para dados brutos e corrigidos. Realizou-se análise da tendência temporal da mortalidade por câncer de pulmão por meio do modelo de regressão com erros autorregressivos. O câncer de pulmão no Brasil apresentou taxas mais elevadas em homens que em mulheres e a região Sul foi a que apresentou maior risco de morte em 1996 e 2011. A mortalidade tendeu a reduzir para o sexo masculino e a aumentar para o sexo feminino. O câncer de pulmão no Brasil apresenta padrão de distribuição diferente segundo sexo, com taxas mais elevadas em homens e com redução da tendência de mortalidade para o sexo masculino e aumento das taxas para o sexo feminino.

Regulando la Enfermedad a través de la Definición y la Restricción: Profesionales de la Salud Hablan sobre el VIH/SIDA1

PubMed Central

Rivera, Souhail Malavé; Díaz, Nelson Varas

2009-01-01

Resumen Las profesiones de la salud tienen un papel social dual. Por un lado, velan por el mantenimiento de la salud de la población protegiendo el bien común. Por el otro, dictaminan las formas saludables, y por lo tanto socialmente apropiadas, de ser, actuar y pensar. Este último papel, está más ligado al control social de la población que a una preocupación altruista hacia la misma. A través de esta supervisión y control, se construyen los sujetos a los cuales todos/as debemos aspirar a ser para gozar de aceptación social. Los/as profesionales de la salud han jugado un rol protagónico en dicho proceso, siendo los agentes que delimitan y definen lo que es enfermo vs. saludable, útil vs. inútil, apropiado vs. inapropiado. En el caso de la epidemia del VIH, este esfuerzo se ha hecho cada vez más vigente ya que estos/as profesionales juegan un papel importante en el tratamiento de las personas que viven con VIH/SIDA (PVVS). Sin embargo, su función está plasmada de definiciones que sirven para criminalizar a las PVVS. El objetivo de este estudio fue explorar la manera en que una muestra de profesionales de la salud en Puerto Rico construyen a las PVVS. Con este propósito, entrevistamos 80 profesionales de la salud y estudiantes de estas profesiones. Estas entrevistas fueron grabadas, transcritas y sometidas a un análisis de discurso. Los resultados reflejaron que según las personas participantes: 1) la PVVS no es una persona “normal” o funcional bajo los estándares sociales debido a que su salud no se los permite, 2) representa una carga para la sociedad incluyendo familiares, amigos/as, el mundo del trabajo, e incluso para el gobierno, 3) debe ser vigilada porque representa un riesgo para la persona seronegativa que es descrita como saludable y productiva, y 4) necesita que su salud y conducta sexual sean controladas por vía legal y/o por las personas que representan las instituciones sociales, como lo son los/as profesionales de la salud. En este artículo abordamos el potencial rol de la psicología para servir como vehículo de reconstrucción de dichas nociones, tomando en consideración su propio rol en la formación y mantenimiento de dicho sujeto socialmente deseable. PMID:22025907

A Diagnostic Assessment for the Teaching of Astronomy. (Spanish Title: Una Evaluación Diagnóstica Para la Enseñanza de la Astronomia.) Uma Avaliação Diagnóstica Para o Ensino da Astronomia

NASA Astrophysics Data System (ADS)

Pacifico Ribeiro de Assis Silveira, Felipa; Soares Gomes de Sousa, Célia Maria; Moreira, Antonio

2011-07-01

This article aims to present the results of a diagnostic evaluation, used as a tool for collecting data on prior knowledge of scientific concepts needed to understand the topic "Earth and Universe", from a group comprised of 47 students of 6th grade. The educational method of diagnosing the student's prior knowledge before teaching them is founded on the Meaningful Learning theory, proposed by David Ausubel. The diagnostic evaluation consisted of 25 questions; the answers were analyzed and categorized, making possible their interpretation, which allows us to understand the meanings assigned by the student to these concepts. It follows from the diagnostic evaluation, that the majority of students surveyed had difficulties in exposing scientific concepts on the topic "Earth and Universe" when starting the 6th grade. However, we identified relevant ideas and representations that contributed to the re-signification of scientific concepts proposed for the teaching of the subject in this grade. The results of diagnostic evaluation served as reference to the organization of the syllabus, making possible the learning process by matching the sequence of teaching to the students" characteristics and context of the classroom. It is expected that other researchers in this topic can also use the instrument presented in this paper. Este artículo tiene como objetivo presentar los resultados de una evaluación diagnóstica, utilizada como una herramienta para recoger datos sobre el conocimiento previo de los conceptos científicos necesarios para comprender el tema "Tierra y Universo", de un grupo compuesto por 47 alumnos de 6º grado de la escuela primaria. La acción pedagógica del diagnóstico de los conocimientos previos del estudiante antes de enseñarles está justificada por la teoría del Aprendizaje Significativo, propuesta por David Ausubel. La evaluación de diagnóstico consistió en 25 preguntas, las respuestas fueron analizadas y clasificadas objetivando-se su interpretación, lo que nos permite comprender los significados asignados por el estudiante a estos conceptos. Se desprende de la evaluación diagnóstica que la mayoría de los encuestados ha tenido dificultades para exponer los conceptos científicos sobre el Universo y la Tierra, para iniciar el 6 º grado. Sin embargo, se identificaron ideas relevantes y las representaciones que contribuyeron a la re-significación de los conceptos científicos propuestos para la enseñanza del tema en esta serie. Los resultados de la evaluación diagnóstica han servido como referencia para la organización del Programa, facilitando el proceso de aprendizaje, haciendo coincidir la secuencia didáctica a las características de los estudiantes y el contexto del aula. Se espera que el instrumento presentado en este documento también pueda ser utilizado por otros investigadores en investigaciones relacionadas con el tema. Este artigo tem como objetivo apresentar os resultados de uma avaliação diagnóstica, utilizada como instrumento para a coleta de dados sobre o conhecimento prévio de conceitos científicos, necessários à compreensão do tema Terra e Universo, de um grupo composto por 47 estudantes, da 6ª série do Ensino Fundamental. A ação pedagógica de diagnosticar os conhecimentos prévios, do estudante, antes de ensiná-los, tem fundamento na teoria da Aprendizagem Significativa, proposta por David Ausubel. Essa avaliação diagnóstica foi composta por 25 questões, cujas respostas foram analisadas e categorizadas visando sua interpretação, o que permitiu compreender os significados atribuídos pelo estudante a esses conceitos. Conclui-se, a partir da avaliação diagnóstica, que a maioria dos estudantes pesquisados apresentou dificuldades em expor conceitos científicos sobre o tema Terra e Universo ao iniciar a 6ª série. Entretanto, foram identificadas ideias e representações relevantes que contribuíram para a (re)significação dos conceitos científicos propostos para o ensino do tema nessa série. Os resultados da avaliação diagnóstica serviram como referência para a organização do plano de ensino, viabilizando o processo de aprendizagem, por adequar a sequência didática às características dos estudantes e ao contexto da sala de aula. É esperado que o instrumento apresentado nesse artigo possa ser utilizado também por outros pesquisadores em investigações relacionadas ao tema.

[Injecting without getting infected: injectors' strategies to prevent HIV and HCV.

PubMed

Mateu-Gelabert, P; Friedman, S; Sandoval, M

2007-10-01

OBJETIVO: Desde principios de los noventa, en la ciudad de Nueva York se han implementado con éxito programas para reducir la incidencia del virus de la inmunodeficiencia humana (VIH) y, en menor medida, del virus de la hepatitis C (VHC). A pesar de ello, aproximadamente el 70% de los usuario de drogas inyectables (UDI) están infectados por el VHC. Queremos investigar cómo el 30% restante se las ha arreglado para no infectarse. El Staying safe (nombre original del estudio) explora los comportamientos y mecanismos que ayudan a evitar la infección por el VHC y el VIH a largo plazo. MATERIAL Y M#ENTITYSTARTX000E9;TODOS: Hemos utilizado el concepto de «desviación positiva» aplicado en otros campos de salud pública. Estudiamos las estrategias, prácticas y tácticas de prevención de aquellos UDI que, viviendo en contextos de alta prevalencia, se mantienen sin infectar por VIH y el VHC, a pesar de haberse inyectado heroína durante años. Los resultados preliminares presentados en este artículo incluyen el análisis de las entrevistas realizadas a 25 UDI (17 doble negativos, 3 doble positivos y 5 con infección por el VHC y sin infección por el VIH). Se usaron entrevistas semiestructuradas que exploraban con detalle la historia de vida de los sujetos, incluyendo su consumo de drogas, redes sociales, contacto con instituciones, relaciones sexuales y estrategias de protección y vigilancia. RESULTADOS: La intencionalidad es importante para no infectarse, especialmente durante períodos de involución (períodos donde hay un deterioro económico y/o social que llevan al que se inyecta a situaciones de mayor riesgo). Presentamos tres dimensiones independientes de intencionalidad que conllevan comportamientos que pueden ayudar a prevenir la infección: a) evitar «el mono» (síntomas de abstención) asegurando el acceso a la droga; b) «llevarlo bien» para no convertirse en un junkie y así evitar la «muerte social» y la falta de acceso a los recursos, y c) seguir sin infectarse por el VIH (sólo un doble negativo tuvo un amplio conocimiento sobre la hepatitis C). Estas intencionalidades no son mutuamente excluyentes. La presencia de varias refuerza la puesta en práctica a diario de comportamientos que pueden ayudar al que se inyecta a mantenerse libre de infecciones durante años. Algunas prácticas que hemos identificado se implementan en grupo y se comunican de UDI a UDI, de esta manera se extienden entre algunas redes sociales de UDI. CONCLUSIONES: Los UDI que permanecen sin infectarse planean e implementan estrategias de prevención en circunstancias donde otros UDI aplican prácticas de riesgo. El mantenimiento de la no infección no es, por lo tanto, un resultado del azar, sino más bien el resultado del esfuerzo (agencia) de los UDI. Investigar y extender estas estrategias y tácticas a través de programas de prevención podría contribuir a la prevención del VIH y el VHC.

Anatomic pulmonary resection by video-assisted thoracoscopy: the Brazilian experience (VATS Brazil study).

PubMed

Terra, Ricardo Mingarini; Kazantzis, Thamara; Pinto-Filho, Darcy Ribeiro; Camargo, Spencer Marcantonio; Martins-Neto, Francisco; Guimarães, Anderson Nassar; Araújo, Carlos Alberto; Losso, Luis Carlos; Ghefter, Mario Claudio; Lima, Nuno Ferreira de; Gomes-Neto, Antero; Brito-Filho, Flávio; Haddad, Rui; Saueressig, Maurício Guidi; Lima, Alexandre Marcelo Rodrigues; Siqueira, Rafael Pontes de; Pinho, Astunaldo Júnior de Macedo E; Vannucci, Fernando

2016-01-01

The objective of this study was to describe the results of anatomic pulmonary resections performed by video-assisted thoracoscopy in Brazil. Thoracic surgeons (members of the Brazilian Society of Thoracic Surgery) were invited, via e-mail, to participate in the study. Eighteen surgeons participated in the project by providing us with retrospective databases containing information related to anatomic pulmonary resections performed by video-assisted thoracoscopy. Demographic, surgical, and postoperative data were collected with a standardized instrument, after which they were compiled and analyzed. The surgeons provided data related to a collective total of 786 patients (mean number of resections per surgeon, 43.6). However, 137 patients were excluded because some data were missing. Therefore, the study sample comprised 649 patients. The mean age of the patients was 61.7 years. Of the 649 patients, 295 (45.5%) were male. The majority-521 (89.8%)-had undergone surgery for neoplasia, which was most often classified as stage IA. The median duration of pleural drainage was 3 days, and the median hospital stay was 4 days. Of the 649 procedures evaluated, 598 (91.2%) were lobectomies. Conversion to thoracotomy was necessary in 30 cases (4.6%). Postoperative complications occurred in 124 patients (19.1%), the most common complications being pneumonia, prolonged air leaks, and atelectasis. The 30-day mortality rate was 2.0%, advanced age and diabetes being found to be predictors of mortality. Our analysis of this representative sample of patients undergoing pulmonary resection by video-assisted thoracoscopy in Brazil showed that the procedure is practicable and safe, as well as being comparable to those performed in other countries. O objetivo deste estudo foi descrever os resultados de ressecções pulmonares anatômicas por videotoracoscopia no Brasil. Cirurgiões torácicos (membros da Sociedade Brasileira de Cirurgia Torácica) foram convidados, por correio eletrônico, a participar do estudo. Dezoito cirurgiões participaram do projeto enviando seus bancos de dados retrospectivos referentes a ressecções anatômicas de pulmão por videotoracoscopia. Dados demográficos, cirúrgicos e pós-operatórios foram coletados em um instrumento padronizado e posteriormente compilados e analisados. Dados referentes a 786 pacientes foram encaminhados (média de 43,6 ressecções por cirurgião), sendo 137 excluídos por informações incompletas. Logo, 649 pacientes constituíram nossa população estudada. A média de idade dos pacientes foi de 61,7 anos, 295 eram homens (45,5%), e a maioria - 521 (89,8%) - foi submetida à cirurgia por neoplasia, mais frequentemente classificada como estádio IA. A mediana do tempo de drenagem pleural foi de 3 dias, e a do tempo de internação, 4 dias. Dos 649 procedimentos realizados, 598 (91,2%) foram lobectomias. A taxa de conversão para toracotomia foi de 4,6% (30 casos). Complicações pós-operatórias ocorreram em 124 pacientes (19,1%), sendo pneumonia, escape aéreo prolongado e atelectasia as mais frequentes. A mortalidade em 30 dias foi de 2,0%, tendo como preditores idade avançada e diabetes. A casuística brasileira mostra que as ressecções pulmonares por cirurgia torácica videoassistida são factíveis e seguras, além de comparáveis àquelas de registros internacionais.

The Moon Phases in a Paper Box. (Spanish Title: Las Fases de la Luna en Una Caja de Cartón.) As Fases da Lua Numa Caixa de Papelão

NASA Astrophysics Data System (ADS)

de Fátima O. Saraiva, Maria; Amador, Cláudio B.; Kemper, Érico; Goulart, Paulo; Muller, Angela

2007-12-01

We present a very simple concrete model to demonstrate the concept of phases of an illuminated body. The main objective of our model is to help the understanding of the Moon phases as viewed from the perspective of an observer on Earth. The material allows the visualization of two important effects: (1st) even though all the time half Moon is illuminated by the Sun, we see different fractions of the illuminated Moon surface, depending on our angle of sight; (2nd) the orientation of the convex part of the Moon in the crescent and waning phases on the sky also depends on our perspective from Earth. The use of a closed box allows one to see the contrast among the different phases with no need of a dark room. We also present a text on the Moon phases, emphasizing the dependence of the aspect of the bright part on the angle of sight. En este trabajo proponemos la construcción de material didáctico de bajo costo para demostración del concepto de fases de un cuerpo iluminado. El principal objetivo de nuestro material es facilitar la comprensión de las fases de la Luna desde la perspectiva de un observador en la Tierra. El material ayuda la visualización de dos efectos importantes: (1º) a pesar de tener siempre la mitad de la Luna (representada por una bolita de espuma plástica o de ping-pong), iluminada por el Sol ( representado por una fuente de luz natural o artificial), vemos diferentes fracciones de su superficie iluminada, dependiendo del ángulo por el cual la vemos; (2º) la orientación del borde convexo de la Luna en las fases Creciente y Menguante también depende de la perspectiva por la cual la miramos desde la Tierra. El uso de una caja cerrada permite observar el contraste entre las diferentes fases sin necesidad de estar en un recinto oscuro. Presentamos también un texto explicativo sobre las fases de la Luna, enfatizando la dependencia de la apariencia de la parte iluminada con el ángulo de visión. Neste trabalho propomos a construção de material didático de baixo custo para demonstração do conceito de fases de um corpo iluminado. O principal objetivo de nosso material é facilitar a compreensão das fases da Lua da perspectiva de um observador na Terra. O material ajuda na visualização de dois efeitos importantes: (1º) mesmo tendo sempre a metade da "Lua" (representada por uma bolinha de isopor ou de ping-pong) iluminada pelo "Sol" (representado por uma fonte de luz natural ou artificial), nós vemos diferentes frações de sua superfície iluminada, dependendo do ângulo pelo qual a olhamos; (2º) a orientação da borda convexa da Lua nas fases Crescente e Minguante também depende da perspectiva pela qual a olhamos da Terra. O uso de uma caixa fechada permite observar o contraste entre as diferentes fases sem necessidade de estar em uma sala escurecida. Apresentamos também um texto explicativo sobre fases da Lua, enfatizando a dependência da aparência da parte iluminada com o ângulo de visada.

AIRUSE-LIFE+: a harmonized PM speciation and source apportionment in 5 Southern European cities

NASA Astrophysics Data System (ADS)

Amato, F.; Alastuey, A.; Karanasiou, A.; Lucarelli, F.; Nava, S.; Calzolai, G.; Severi, M.; Becagli, S.; Gianelle, V. L.; Colombi, C.; Alves, C.; Custódio, D.; Nunes, T.; Cerqueira, M.; Pio, C.; Eleftheriadis, K.; Diapouli, E.; Reche, C.; Minguillón, M. C.; Manousakas, M.; Maggos, T.; Vratolis, S.; Harrison, R. M.; Querol, X.

2015-09-01

The AIRUSE-LIFE+ project aims at characterising similarities and heterogeneities in PM sources and contributions in urban areas from the Southern Europe. Once the main PMx sources are identified, AIRUSE aims at developing and testing the efficiency of specific and non-specific measures to improve urban air quality. This article reports the results of the source apportionment of PM10 and PM2.5 conducted at three urban background sites (Barcelona, Florence and Milan, BCN-UB, FI-UB, MLN-UB) one sub-urban background site (Athens, ATH-SUB) and one traffic site (Porto, POR-TR). After collecting 1047 PM10 and 1116 PM2.5 24 h samples from January 2013 to February 2014 simultaneously at the 5 cities, these were analysed for the contents of OC, EC, anions, cations, major and trace elements and levoglucosan. The USEPA PMF5 receptor model was applied to these datasets in a harmonised way for each city. The sum of vehicle exhaust and non-exhaust contributes within 3.9-10.8 μg m-3 (16-32 %) to PM10 and 2.3-9.4 μg m-3 (15-36 %) to PM2.5, although a fraction of secondary nitrate is also traffic-related but could not be estimated. Important contributions arise from secondary particles (nitrate, sulphate and organics) in PM2.5 (37-82 %) but also in PM10 (40-71 %) mostly at background sites, revealing the importance of abating gaseous precursors in designing air quality plans. Biomass burning (BB) contributions vary widely, from 14-24 % of PM10 in POR-TR, MLN-UB and FI-UB, 7 % in ATH-SUB to < 2 % in BCN-UB. In PM2.5, BB is the second most important source in MLN-UB (21 %) and in POR-TR (18 %), the third one in FI-UB (21 %) and ATH-SUB (11 %), but again negligible (< 2 %) in BCN-UB. This large variability among cities is mostly due to the degree of penetration of biomass for residential heating. In Barcelona natural gas is very well supplied across the city and used as fuel in 96 % of homes, while, in other cities, PM levels increase on an annual basis by 1-9 μg m-3 due to this source. Other significant sources are: - Local dust, 7-12 % of PM10 at SUB and UB sites and 19 % at the TR site, revealing a contribution from road dust resuspension. In PM2.5 percentages decrease to 2-7 % at SUB-UB sites and 15 % at the TR site. - Industries, mainly metallurgy, contributing 4-11 % of PM10 (5-12 % in PM2.5), but only at BCN-UB, POR-TR and MLN-UB. No clear impact of industrial emissions was found in FI-UB and ATH-SUB. - Natural contributions from sea salt (13 % of PM10 in POR-TR but only 2-7 % in the other cities) and Saharan dust (14 % in ATH-SUB), but less than 4 % in the other cities. During high pollution days, the largest specific source (i.e. excluding SSO and SNI) of PM10 and PM2.5 are: VEX+NEX in BCN-UB (27-22 %) and POR-TR (31-33 %), BB in FI-UB (30-33 %) and MLN-UB (35-26 %) and Saharan dust in ATH-SUB (52-45 %) During those days, there are also quite important Industrial contributions in BCN-UB (17-18 %) and Local dust in POR-TR (28-20 %).

Study and optimization of the macroscopic electrical response of carbon based nanocomposites for advanced applications

NASA Astrophysics Data System (ADS)

Silva, Jaime Pedro Oliveira da

A presente tese centrou-se no estudo da resposta da constante dieletrica e condutividade eletrica em materiais compositos nos quais o reforco tinha uma elevada proporcao entre comprimento e diametro. O objeto de estudo foi o efeito de um reforco com uma elevada razao entre comprimento e diametro, concentracao e orientacao na resposta eletrica e dieletrica de um composito. Estes compositos tem uma grande importancia no desenvolvimento de materiais para sensores e atuadores. Num primeiro momento da dissertacao, explorou-se a resposta da constante dieletrica de um composito constituido por nanotubos de carbono como reforco e uma matriz polimerica. Verificou-se que um aumento da razao entre comprimento e diametro do reforco tem o efeito de aumentar a constante dieletrica do composito para uma igual fracao volumetrica de reforco. Constatou-se tambem que materiais na fase nematica demonstram uma constante dieletrica mais baixa quando comparados com materiais onde o reforco esta distribuido aleatoriamente. Ficou ainda demonstrado nesta dissertacao que materiais na fase nematica com razoes entre o comprimento e diametro diferentes a constante dieletrica segue uma lei de potencia. Numa segunda fase do trabalho, foi explorada a condutividade de nanocompositos polimericos reforcados com nanotubos de carbono, atraves de um modelo baseado em cilindros impenetraveis. Ficou demonstrado que o modelo e apropriado para descrever a condutividade eletrica de um nanocomposito polimerico reforcado com nanotubos. As simulacoes desenvolvidas demonstram que, aumentando a razao entre o comprimento e o diametro dos nanotubos de carbono, aumenta a condutividade eletrica do nanocomposito. No entanto, verifica-se que aumentando a anisotropia diminui a condutividade, sendo este efeito mais evidente para fracoes volumetricas maiores. Nesta dissertacao comprovou-se ainda que uma microestrutura gerada por um algoritmo de empacotamento sequencial pode ser descrita por um grafo aleatorio e que a condutividade num composito reforcado com nanofibras de carbono pode ser descrito por uma rede de Bethe. Atraves do uso da teoria das redes complexas, chegou-se a uma expressao para o limite de percolacao e, do mesmo modo, demonstrou-se que “hopping” entre fibras adjacentes resulta numa expressao que corresponde a um regime de desordem fraca. No trabalho desenvolvido tambem foi calculado os expoentes criticos, atraves da teoria das redes, para um sistema 3D composto por cilindros impenetraveis com uma interacao de curto alcance, demonstrando que os expoentes criticos estao relacionados por uma relacao de hiperescala comum para 3D e nao pertencem a mesma classe de universalidade como a percolacao numa rede. A aplicacao do modelo desenvolvido a compositos de epoxy reforcada, com diferentes metodos de dispersao de nanofibras de carbono, revelou que os metodos de dispersao usados para preparar os compositos tem uma forte influencia nas propriedades eletricas que podem ser capturadas pelo modelo. Neste contexto, ficou ainda demonstrado que a condutividade eletrica pode ser descrita por um regime de desordem fraca, isto ´e, um regime onde todas as conexoes fibra-fibra participam na condutividade do composito. O modelo desenvolvido foi aplicado igualmente a compositos de poly (vinylidene fluoride) reforcado com nanotubos de carbono com diferentes tratamentos de termicos de oxidacao. Verificou-se que os tratamentos de superficie aumentam o limite de percolacao e diminuem a condutividade. Nesta dissertacao provamos ainda que a condutividade do composito pode ser atribuida a um mecanismo de “hopping”, fortemente afetado pelos tratamentos de superficie dos reforcos.

AIRUSE-LIFE+: a harmonized PM speciation and source apportionment in five southern European cities

NASA Astrophysics Data System (ADS)

Amato, Fulvio; Alastuey, Andrés; Karanasiou, Angeliki; Lucarelli, Franco; Nava, Silvia; Calzolai, Giulia; Severi, Mirko; Becagli, Silvia; Gianelle, Vorne L.; Colombi, Cristina; Alves, Celia; Custódio, Danilo; Nunes, Teresa; Cerqueira, Mario; Pio, Casimiro; Eleftheriadis, Konstantinos; Diapouli, Evangelia; Reche, Cristina; Cruz Minguillón, María; Manousakas, Manousos-Ioannis; Maggos, Thomas; Vratolis, Stergios; Harrison, Roy M.; Querol, Xavier

2016-03-01

The AIRUSE-LIFE+ project aims at characterizing similarities and heterogeneities in particulate matter (PM) sources and contributions in urban areas from southern Europe. Once the main PMx sources are identified, AIRUSE aims at developing and testing the efficiency of specific and non-specific measures to improve urban air quality. This article reports the results of the source apportionment of PM10 and PM2.5 conducted at three urban background sites (Barcelona, Florence and Milan, BCN-UB, FI-UB and MLN-UB), one suburban background site (Athens, ATH-SUB) and one traffic site (Porto, POR-TR). After collecting 1047 PM10 and 1116 PM2.5 24 h samples during 12 months (from January 2013 on) simultaneously at the five cities, these were analysed for the contents of OC, EC, anions, cations, major and trace elements and levoglucosan. The USEPA PMF5 receptor model was applied to these data sets in a harmonized way for each city. The sum of vehicle exhaust (VEX) and non-exhaust (NEX) contributes between 3.9 and 10.8 µg m-3 (16-32 %) to PM10 and 2.3 and 9.4 µg m-3 (15-36 %) to PM2.5, although a fraction of secondary nitrate is also traffic-related but could not be estimated. Important contributions arise from secondary particles (nitrate, sulfate and organics) in PM2.5 (37-82 %) but also in PM10 (40-71 %), mostly at background sites, revealing the importance of abating gaseous precursors in designing air quality plans. Biomass burning (BB) contributions vary widely, from 14-24 % of PM10 in POR-TR, MLN-UB and FI-UB, 7 % in ATH-SUB, to < 2 % in BCN-UB. In PM2.5, BB is the second most important source in MLN-UB (21 %) and in POR-TR (18 %), the third one in FI-UB (21 %) and ATH-SUB (11 %), but is again negligible (< 2 %) in BCN-UB. This large variability among cities is mostly due to the degree of penetration of biomass for residential heating. In Barcelona natural gas is very well supplied across the city and is used as fuel in 96 % of homes, while in other cities, PM levels increase on an annual basis by 1-9 µg m-3 due to biomass burning influence. Other significant sources are the following. - Local dust, 7-12 % of PM10 at SUB and UB sites and 19 % at the TR site, revealing a contribution from road dust resuspension. In PM2.5 percentages decrease to 2-7 % at SUB-UB sites and 15 % at the TR site. - Industry, mainly metallurgy, contributing 4-11 % of PM10 (5-12 % in PM2.5), but only at BCN-UB, POR-TR and MLN-UB. No clear impact of industrial emissions was found in FI-UB and ATH-SUB. - Natural contributions from sea salt (13 % of PM10 in POR-TR, but only 2-7 % in the other cities) and Saharan dust (14 % in ATH-SUB, but less than 4 % in the other cities). During high pollution days, the largest sources (i.e. excluding secondary aerosol factors) of PM10 and PM2.5 are VEX + NEX in BCN-UB (27-22 %) and POR-TR (31-33 %), BB in FI-UB (30-33 %) and MLN-UB (35-26 %) and Saharan dust in ATH-SUB (52-45 %). During those days, there are also quite important industrial contributions in BCN-UB (17-18 %) and local dust in POR-TR (28-20 %).

Effects of Air Pollutant Exposure on Acute Myocardial Infarction, According to Gender.

PubMed

Tuan, Tássia Soldi; Venâncio, Taís Siqueira; Nascimento, Luiz Fernando Costa

2016-09-01

There is evidence of the effects of air pollution on hospital admissions due to cardiovascular diseases, including myocardial infarction. To estimate the association between exposure to air pollutants and hospital admissions due to myocardial infarction according to gender, between January 1st 2012 and December 31st 2013, in São Jose dos Campos-SP. An ecological time series study was carried out with daily data of admissions due to AMI, pollutants CO, O3, PM10, SO2, and NO2, according to gender. We used the Poisson regression generalized linear model to estimate the relative risks of hospital admissions with lags of 0-5 days, adjusted for temperature, humidity, seasonality and days of the week. There were 1837 admissions for ischemic heart diseases, with 636 women and 1201 men. For females, the risks were significant for CO in lag 0 (RR = 1,09), lag1 (RR = 1,08) and lag 5 (RR = 1,10) and SO2 in lag 0 (RR = 1,10) and 3 (RR = 1,09). For men there was significance of the CO in, lag 3 and lag 5 (RR = 1,05). There was significance, regardless of gender, for CO at lag 1 (RR = 1,05) and lag 5 (RR = 1,07) and lag 0 for SO2 (RR = 1,06). The data presented show the important role of CO and SO2 in the genesis of myocardial infarction admissions, and responses to pollutant exposure are different if analyzed by gender and together - hence the importance of a stratified analyses. Existem evidências sobre os efeitos da poluição do ar nas internações por doenças cardiovasculares, entre elas o infarto do miocárdio. Estimar a associação entre exposição a poluentes do ar e internações por infarto segundo gêneros, entre 01 de Janeiro de 2012 e 31 de Dezembro de 2013, em São José dos Campos - SP. Estudo ecológico de série temporal com dados diários de internações por IAM dos poluentes CO, O3, PM10, SO2, NO2, segundo gêneros. Utilizou-se modelo linear generalizado da Regressão de Poisson para estimar os riscos relativos para internações com defasagens de 0 a 5 dias, ajustados por temperatura, umidade, sazonalidade e dias da semana. Foram 1837 internações por doenças isquêmicas do coração, sendo 636 mulheres e 1201 homens. Para o gênero feminino, os riscos foram significativos para o CO nos lag 0 (RR = 1,09), lag1 (RR = 1,08) e lag 5 (RR = 1,10) e para o SO2 no lag 0 (RR = 1,10) e 3 (RR = 1,09). Para o gênero masculino houve significância para o CO no lag 3 e lag 5 (RR = 1,05). Sem distinção de gênero houve significância para o CO no lag 1 (RR = 1,05) e lag 5 (RR = 1,07) e no lag 0 para o SO2 (RR = 1,06). Os dados apresentados mostram o importante papel do CO e do SO2 na gênese das internações por infarto e que as respostas à exposição aos poluentes são diferentes se analisadas por sexo e em conjunto, daí a importância de se estratificarem as análises.

Espectroscopía de Microondas en Jets Supersónicos

NASA Astrophysics Data System (ADS)

Alonso, J. L.; López, J. C.; Lesarri, A.; Blanco, S.; Sanz, M. E.; Mata, S.; Cocinero, J. E.; Sánchez, R.

Complejos con Enlace de Hidrógeno. El entorno de bajas temperaturas de una expansión supersónica es un excelente laboratorio para estudiar el comportamiento conformacional de los complejos con enlace de hidrógeno. Nuestro grupo ha observado por vez primera enlaces de hidrógeno axial y ecuatorial en los complejos de tetrahidropirano, sulfuro de pentametileno y sulfuro de trimetileno con HCl y HF [1-6] generados en las expansiones adiabáticas en He, Ne o Ar y caracterizados por espectroscopía de microondas con transformadas de Fouier. Existe controversia a la hora de considerar a las interacciones C-H\\cdotsO como enlaces de hidrógeno o como simples interacciones de van der Waals. Las interacciones C-H\\cdotsO han sido estudiadas en el dímero del dimetil eter generado en la expansión supersónica y caracterizado por espectroscopía de microondas [7]. Estas interacciones se han analizado en los complejos formados entre los alcanos sustituidos del trifluorometano y difluorometano con oxirano [8] caracterizándose la existencia de interacciones C-F\\cdotsH-C que contribuyen a la estabilización de estos complejos. Ablación Láser: Estructura de Aminoácidos. Los aminoácidos poseen puntos de fusión elevados (>200oC) y se presentan en fases condensadas como formas dipolares (+H3N-CH(R)-COO-) distintas de las neutras de las cadenas polipéptidas. Con el fin de obtener la estructura de estas formas neutras es necesario experimentar en fase gas, en un entorno libre de interacciones como el de una expansión supersónica. Para solventar el problema de su baja presión de vapor, se ha diseñado un nuevo instrumento que combina la espectroscopía de microondas en jet supersónicos con técnicas de ablación láser [9] que evita los métodos de vaporización por calentamiento que conducen a la descomposición de los aminoácidos. Diversos confórmeros de los aminoácidos naturales de la prolina [10], valina [11], cis- y trans- hidroxiprolina, serina, cisteina, ldots han sido caracterizados hasta el presente. Con este mismo dispositivo experimental de ablación láser ha sido igualmente posible generar clusters metálicos como los de Si3, Se-Te, ldots. entre otros. Moléculas generadas por descargas eléctricas. Utilizando diferentes precursores (1,1-difluoroetileno, trifluoroacetileno, acetileno, ldots) diversos fluoropoliinos [12] y fluorometilpoliinos [13] han sido por primera vez generados y caracterizados por sus espectros de rotación en la expansión adiabática de un instrumento de MBFTMW dotado de un dispositivo de descargas. Solvatación en fase gas. La formación de complejos de biomoléculas con agua en fase gas es de gran importancia para entender la naturaleza de la solvatación a escala microscópica. Los complejos indol\\cdotsH2O [14], glicina\\cdotsH2O (mediante ablación láser) azetidinona\\cdotsH2O, azetidinona\\cdots2H2O, ldots entre otros, han sido analizados en fase gas.

No increase in HIV or sexually transmissible infection testing following a social marketing campaign among men who have sex with men.

PubMed

Guy, R; Goller, J; Leslie, D; Thorpe, R; Grierson, J; Batrouney, C; Kennedy, M; Lewis, J; Fairley, C; Ginige, S; Zablotska, I; Hellard, M

2009-05-01

A social marketing campaign ran in 2004 in the Victoria to increase rates of HIV/sexually transmissible infection (STI) testing among men having sex with men (MSM). To evaluate the initiative data from HIV sentinel surveillance, laboratory data on testing for HIV/STIs and STI/HIV testing uptake reported in annual surveys were analysed. The sentinel surveillance network showed no increase in the overall extent of HIV testing and no difference in the proportion of MSM reporting regular annual HIV testing during the campaign (43%) and post campaign (41%). The annual behavioural surveys showed that between 2004 and 2006 there was no significant increase in this overall proportion of MSM reporting having an HIV test in the last 12 months (p = 0.96). The behavioural surveys also showed an increasing trend in the proportion reporting specific STI tests over time: anal swab (26% to 39%, p

Characterization of the Porphyromonas gingivalis conjugative transposon CTnPg1: determination of the integration site and the genes essential for conjugal transfer.

PubMed

Naito, Mariko; Sato, Keiko; Shoji, Mikio; Yukitake, Hideharu; Ogura, Yoshitoshi; Hayashi, Tetsuya; Nakayama, Koji

2011-07-01

In our previous study, extensive genomic rearrangements were found in two strains of the Gram-negative anaerobic bacterium Porphyromonas (Por.) gingivalis, and most of these rearrangements were associated with mobile genetic elements such as insertion sequences and conjugative transposons (CTns). CTnPg1, identified in Por. gingivalis strain ATCC 33277, was the first complete CTn reported for the genus Porphyromonas. In the present study, we found that CTnPg1 can be transferred from strain ATCC 33277 to another Por. gingivalis strain, W83, at a frequency of 10(-7) to 10(-6). The excision of CTnPg1 from the chromosome in a donor cell depends on an integrase (Int; PGN_0094) encoded in CTnPg1, whereas CTnPg1 excision is independent of PGN_0084 (a DNA topoisomerase I homologue; Exc) encoded within CTnPg1 and recA (PGN_1057) on the donor chromosome. Intriguingly, however, the transfer of CTnPg1 between Por. gingivalis strains requires RecA function in the recipient. Sequencing analysis of CTnPg1-integrated sites on the chromosomes of transconjugants revealed that the consensus attachment (att) sequence is a 13 bp sequence, TTTTCNNNNAAAA. We further report that CTnPg1 is able to transfer to two other bacterial species, Bacteroides thetaiotaomicron and Prevotella oralis. In addition, CTnPg1-like CTns are located in the genomes of other oral anaerobic bacteria, Porphyromonas endodontalis, Prevotella buccae and Prevotella intermedia, with the same consensus att sequence. These results suggest that CTns in the CTnPg1 family are widely distributed among oral anaerobic Gram-negative bacteria found in humans and play important roles in horizontal gene transfer among these bacteria.

Structural and regulatory mutations in Vibrio parahaemolyticus type III secretion systems display variable effects on virulence.

PubMed

Calder, Thomas; de Souza Santos, Marcela; Attah, Victoria; Klimko, John; Fernandez, Jessie; Salomon, Dor; Krachler, Anne-Marie; Orth, Kim

2014-12-01

The Gram-negative bacterium, Vibrio parahaemolyticus, is a major cause of seafood-derived food poisoning throughout the world. The pathogenicity of V. parahaemolyticus is attributed to several virulence factors, including two type III secretion systems (T3SS), T3SS1 and T3SS2. Herein, we compare the virulence of V. parahaemolyticus POR strains, which harbor a mutation in the T3SS needle apparatus of either system, to V. parahaemolyticus CAB strains, which harbor mutations in positive transcriptional regulators of either system. These strains are derived from the clinical RIMD 2210633 strain. We demonstrate that each mutation affects the virulence of the bacterium in a different manner. POR and CAB strains exhibited similar levels of swarming motility and T3SS effector production and secretion, but the CAB3 and CAB4 strains, which harbor a mutation in the T3SS2 master regulator gene, formed reduced biofilm growth under T3SS2 inducing conditions. Additionally, while the cytotoxicity of the POR and CAB strains was similar, the CAB2 (T3SS1 regulatory mutant) strain was strikingly more invasive than the comparable POR2 (T3SS1 structural mutant) strain. In summary, creating structural or regulatory mutations in either T3SS1 or T3SS2 causes differential downstream effects on other virulence systems. Understanding the biological differences of strains created from a clinical isolate is critical for interpreting and understanding the pathogenic nature of V. parahaemolyticus. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Possible association between different congenital abnormalities and use of different sulfonamides during pregnancy.

PubMed

Czeizel, Andrew E; Puhó, Erzsébet; Sørensen, Henrik T; Olsen, Jørn

2004-06-01

The objective of the study presented here was to check the debated human teratogenic potential of sulfonamide drugs. Five different sulfonamides such as sulfamethazine, sulfathiourea, sulfamethoxypyridazine, sulfamethoxydiazine and the combination of sulfamethazine-sulfathiourea-sulfamethoxypyridazine were differentiated. Cases with congenital abnormalities were compared with their matched controls without congenital abnormalities in the population-based large data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities between 1980 and 1996. Of 38,151 newborn infants without any congenital abnormalities (control group), 163 (0.4%) had mothers who were treated with the sulfonamides studied during pregnancy, while of 22,843 cases with congenital abnormalities, 140 (0.6%) had mothers who were treated with the sulfonamides studied during pregnancy. The analysis of cases and matched controls indicated a higher rate of cardiovascular malformation (adjusted prevalence odds ratios [POR] with 95% CI: 3.5, 1.9-6.4) and clubfoot (adjusted POR with 95% CI: 2.6, 1.1-6.2) in infants born to mothers with sulfonamide treatment in the second and third months of pregnancy. The detailed analysis of different sulfonamides showed a possible association between cardiovascular malformations (adjusted POR with 95%; CI: 6.5, 2.6-15.9), particularly ventricular septal defect (17.1, 1.3-141.1) and sulfamethoxydiazine during the second and third months of pregnancy. In addition, a possible association was found between clubfoot and sulfathiourea, both during the entire pregnancy (adjusted POR with 95% CI: 2.3, 1.2-4.3) and in the second and third months of gestation (3.9, 1.1-13.8). Thus, maternal treatment of sulfamethoxydiazine may cause ventricular septal defect, while sulfathiourea may induce clubfoot; however, further studies are needed to verify or reject these associations.

Carriage rates and serogroups of Neisseria meningitidis among freshmen in a University dormitory in Korea.

PubMed

Durey, Areum; Bae, Song-Mee; Lee, Hye-Jin; Nah, So-Yun; Kim, Mijeong; Baek, Ji Hyeon; Kang, Yeon-Ho; Chung, Moon-Hyun; Lee, Jin-Soo

2012-07-01

Neisseria meningitidis is a leading cause of bacterial meningitis in young adults. University students, especially those living in dormitories, have been known to be at increased risk of meningococcal disease. We performed a longitudinal study to determine the carriage rates of N. meningitidis and the changes thereof. We recruited Inha University freshmen who were, at that time, admitted to a student dormitory. A pharyngeal swab was taken from all participant who were also asked to complete a questionnaire. This was repeated four weeks later. A total of 136 students were enrolled at the first culture. After four weeks, 128 students were enrolled, including 106 re-participants. The overall carriage rates changed from 11.8% to 14.1%. In analysis of the 106 re-participants, "visiting to pubs" was associated with carriage of N. meningitis for both the first (p=0.047) and second cultures (p=0.026). Serogroup C was found to be the most frequent serogroup (5 isolates), while 3 isolates were found from serogroup B. The most prevalent PorA types were P1.22,14-6 (4 isolates) and P1.19,15 (3 isolates). The DNA sequences of PorA VR2 were changed in 2 students during prolonged carriage. The meningococcal carriage rate among first year university students who resided in a dormitory did not significantly increase over 4-week interval between cultures, which is markedly different from those reported in Western studies. Close social contact appeared to be related with carriage. Our data also revealed diversity in PorA types, suggesting the possibility of rapid mutation of the PorA gene during the 4-week interval.

Carriage Rates and Serogroups of Neisseria meningitidis among Freshmen in a University Dormitory in Korea

PubMed Central

Durey, Areum; Bae, Song-Mee; Lee, Hye-Jin; Nah, So-Yun; Kim, Mijeong; Baek, Ji Hyeon; Kang, Yeon-Ho; Chung, Moon-Hyun

2012-01-01

Purpose Neisseria meningitidis is a leading cause of bacterial meningitis in young adults. University students, especially those living in dormitories, have been known to be at increased risk of meningococcal disease. We performed a longitudinal study to determine the carriage rates of N. meningitidis and the changes thereof. Materials and Methods We recruited Inha University freshmen who were, at that time, admitted to a student dormitory. A pharyngeal swab was taken from all participant who were also asked to complete a questionnaire. This was repeated four weeks later. Results A total of 136 students were enrolled at the first culture. After four weeks, 128 students were enrolled, including 106 re-participants. The overall carriage rates changed from 11.8% to 14.1%. In analysis of the 106 re-participants, "visiting to pubs" was associated with carriage of N. meningitis for both the first (p=0.047) and second cultures (p=0.026). Serogroup C was found to be the most frequent serogroup (5 isolates), while 3 isolates were found from serogroup B. The most prevalent PorA types were P1.22,14-6 (4 isolates) and P1.19,15 (3 isolates). The DNA sequences of PorA VR2 were changed in 2 students during prolonged carriage. Conclusion The meningococcal carriage rate among first year university students who resided in a dormitory did not significantly increase over 4-week interval between cultures, which is markedly different from those reported in Western studies. Close social contact appeared to be related with carriage. Our data also revealed diversity in PorA types, suggesting the possibility of rapid mutation of the PorA gene during the 4-week interval. PMID:22665340

Homozygous Mutation G539R in the Gene for P450 Oxidoreductase in a Family Previously Diagnosed as Having 17,20-Lyase Deficiency

PubMed Central

Hershkovitz, Eli; Parvari, Ruthi; Wudy, Stefan A.; Hartmann, Michaela F.; Gomes, Larissa G.; Loewental, Neta; Miller, Walter L.

2008-01-01

Context: Very few patients have been described with isolated 17,20-lyase deficiency who have had their mutations in P450c17 (17α-hydroxylase/17,20-lyase) proven by DNA sequencing and in vitro characterization of the mutations. Most patients with 17,20-lyase deficiency have mutations in the domain of P450c17 that interact with the electron-donating redox partner, P450 oxidoreductase (POR). Objective: Our objective was to clarify the genetic and functional basis of isolated 17,20-lyase deficiency in familial cases who were previously reported as having 17,20-lyase deficiency. Patients: Four undervirilized males of an extended Bedouin family were investigated. One of these has previously been reported to carry mutations in the CYP17A1 gene encoding P450c17 causing isolated 17,20-lyase deficiency. Methods: Serum hormones were evaluated before and after stimulation with ACTH. Urinary steroid metabolites were profiled by gas chromatography-mass spectrometry. Exons 1 and 8 of CYP17A1 previously reported to harbor mutations in one of these patients and all 15 coding exons of POR were sequenced. Results: Gas chromatography-mass spectrometry (GC-MS) urinary steroid profiling and serum steroid measurements showed combined deficiencies of 17,20-lyase and 21-hydroxylase. Sequencing of exons 1 and 8 of CYP17A1 in two different laboratories showed no mutations. Sequencing of POR showed that all four patients were homozygous for G539R, a previously studied mutation that retains 46% of normal capacity to support the 17α-hydroxylase activity but only 8% of the 17,20-lyase activity of P450c17. Conclusion: POR deficiency can masquerade clinically as isolated 17,20-lyase deficiency. PMID:18559916

Homozygous mutation G539R in the gene for P450 oxidoreductase in a family previously diagnosed as having 17,20-lyase deficiency.

PubMed

Hershkovitz, Eli; Parvari, Ruthi; Wudy, Stefan A; Hartmann, Michaela F; Gomes, Larissa G; Loewental, Neta; Miller, Walter L

2008-09-01

Very few patients have been described with isolated 17,20-lyase deficiency who have had their mutations in P450c17 (17alpha-hydroxylase/17,20-lyase) proven by DNA sequencing and in vitro characterization of the mutations. Most patients with 17,20-lyase deficiency have mutations in the domain of P450c17 that interact with the electron-donating redox partner, P450 oxidoreductase (POR). Our objective was to clarify the genetic and functional basis of isolated 17,20-lyase deficiency in familial cases who were previously reported as having 17,20-lyase deficiency. Four undervirilized males of an extended Bedouin family were investigated. One of these has previously been reported to carry mutations in the CYP17A1 gene encoding P450c17 causing isolated 17,20-lyase deficiency. Serum hormones were evaluated before and after stimulation with ACTH. Urinary steroid metabolites were profiled by gas chromatography-mass spectrometry. Exons 1 and 8 of CYP17A1 previously reported to harbor mutations in one of these patients and all 15 coding exons of POR were sequenced. Gas chromatography-mass spectrometry (GC-MS) urinary steroid profiling and serum steroid measurements showed combined deficiencies of 17,20-lyase and 21-hydroxylase. Sequencing of exons 1 and 8 of CYP17A1 in two different laboratories showed no mutations. Sequencing of POR showed that all four patients were homozygous for G539R, a previously studied mutation that retains 46% of normal capacity to support the 17alpha-hydroxylase activity but only 8% of the 17,20-lyase activity of P450c17. POR deficiency can masquerade clinically as isolated 17,20-lyase deficiency.

HIV and syphilis infection among men attending a [corrected] sexually transmitted infection clinic in Puerto Rico.

PubMed

Colón-López, Vivian; Ortiz, Ana P; Banerjee, Geetanjoli; Gertz, Alida M; García, Hermes

2013-03-01

This study aimed to assess the demographic, behavioral, and clinical factors associated with HIV and syphilis infection among a sample of men attending a sexually transmitted infection clinic during 2009 to 2010 in San Juan, Puerto Rico (PR). A sample of 350 clinical records from men visiting the clinic for the first time during 2009 to 2010 was reviewed. Descriptive statistics were used to describe the study sample, and bivariate analyses were performed separately for HIV and syphilis to identify factors associated with these infectious diseases. Variables that were significantly associated (p < 0.05) with HIV and syphilis in the bivariate analysis were considered for inclusion in the logistic regression models. Overall, 11.2% and 14.1% of the men were infected with HIV and syphilis, respectively, and 5.1% were coinfected with HIV and syphilis. In multivariate logistic regression models, ever injecting drugs (POR = 8.1; 95% CI 3.0, 21.8) and being a man who has sex with men (MSM) (POR = 5.3; 95% CI 2.3, 11.9) were positively associated with HIV infection. Being a man older than 45 years (POR = 4.0; 95% CI: 1.9, 8.9) and being an MSM (POR = 2.5; 95% CI: 1.3, 4.9) were both significantly associated with syphilis infection. These findings reinforce the need for greater education and prevention efforts for HIV and other STIs among men in PR, particularly those who are MSM. However, there is a need to make an a priori assessment of the level of health literacy in the members of this group so that a culturally sensitive intervention can be provided to the men who attend this STI clinic.

HIV and Syphilis Infection among Men attending a Sexually Transmitted Infection Clinic in Puerto Rico

PubMed Central

Colón-López, Vivian; Ortiz, Ana P.; Banerjee, Geetanjoli; Gertz, Alida M.; García, Hermes

2013-01-01

Objective This study aimed to assess the demographic, behavioral, and clinical factors associated with HIV and syphilis infection among a sample of men attending a sexually transmitted infection clinic during 2009 to 2010 in San Juan, Puerto Rico (PR). Methods A sample of 350 clinical records from men visiting the clinic for the first time during 2009 to 2010 was reviewed. Descriptive statistics were used to describe the study sample, and bivariate analyses were performed separately for HIV and syphilis to identify factors associated with these infectious diseases. Variables that were significantly associated (p<0.05) with HIV and syphilis in the bivariate analysis were considered for inclusion in the logistic regression models. Results Overall, 11.2% and 14.1% of the men were infected with HIV and syphilis, respectively, and 5.1% were coinfected with HIV and syphilis. In multivariate logistic regression models, ever injecting drugs (POR = 8.1; 95%Cl 3.0, 21.8) and being a man who has sex with men (MSM) (POR = 5.3; 95%CI 2.3, 11.9) were positively associated with HIV infection. Being a man older than 45 years (POR = 4.0; 95%CI: 1.9, 8.9) and being an MSM (POR = 2.5; 95%CI: 1.3, 4.9) were both significantly associated with syphilis infection. Conclusion These findings reinforce the need for greater education and prevention efforts for HIV and other STIs among men in PR, particularly those who are MSM. However, there is a need to make an a priori assessment of the level of health literacy in the members of this group so that a culturally sensitive intervention can be provided to the men who attend this STI clinic. PMID:23556260

Comparative pan genome analysis of oral Prevotella species implicated in periodontitis.

PubMed

Ibrahim, Maziya; Subramanian, Ahalyaa; Anishetty, Sharmila

2017-09-01

Prevotella is part of the oral bacterial community implicated in periodontitis. Pan genome analyses of eight oral Prevotella species, P. dentalis, P. enoeca, P. fusca, P. melaninogenica, P. denticola, P. intermedia 17, P. intermedia 17-2 and P. sp. oral taxon 299 are presented in this study. Analysis of the Prevotella pan genome revealed features such as secretion systems, resistance to oxidative stress and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas systems that enable the bacteria to adapt to the oral environment. We identified the presence of type VI secretion system (T6SS) in P. fusca and P. intermedia strains. For some VgrG and Hcp proteins which were not part of the core T6SS loci, we used gene neighborhood analysis and identified putative effector proteins and putative polyimmunity loci in P. fusca and polymorphic toxin systems in P. intermedia strains. Earlier studies have identified the presence of Por secretion system (PorSS) in P. gingivalis, P. melaninogenica and P. intermedia. We noted the presence of their homologs in six other oral Prevotella studied here. We suggest that in Prevotella, PorSS is used to secrete cysteine proteases such as interpain and C-terminal domain containing proteins with a "Por_secre_tail" domain. We identified subtype I-B CRISPR-Cas system in P. enoeca. Putative CRISPR-Cas system subtypes for 37 oral Prevotella and 30 non-oral Prevotella species were also predicted. Further, we performed a BLASTp search of the Prevotella proteins which are also conserved in the red-complex pathogens, against the human proteome to identify potential broad-spectrum drug targets. In summary, the use of a pan genome approach enabled identification of secretion systems and defense mechanisms in Prevotella that confer adaptation to the oral cavity.

PubMed

Müller Velázquez, Lucía; Bobadilla, Fernando; Novosak, Marina; Cortese, Iliana; Laczeski, Margarita

2018-03-20

Streptococcus agalactiae (SGB) es causa de infecciones severas en menores de tres meses. Meningitis, neumonía y sepsis son los principales cuadros en estos niños. Estas infecciones se encuentran entre las más graves que puede sufrir un individuo en sus primeras doce horas de vida. El niño adquiere la infección por transmisión vertical de la madre colonizada. Para prevenir la enfermedad neonatal se recomienda penicilina como droga de elección en la profilaxis intraparto (PIP) en embarazadas colonizadas. Sin embargo, actualmente se han detectado cepas con sensibilidad disminuida a penicilina por lo que resulta importante realizar la vigilancia de la sensibilidad al mismo para asegurar su utilidad durante la profilaxis. El objetivo de este trabajo fue determinar la sensibilidad a penicilina en cepas de SGB recuperados de mujeres embarazadas de 35-37 semanas de gestación. Se estudiaron 96 aislamientos y se determinó la sensibilidad por método epsilométrico Etest® (LIOFILCHEM, Italia), siguiendo las recomendaciones del Clinical Laboratory Standards Institute (CLSI). Se obtuvo la Concentración Inhibitoria Mínima (CIM) para cada aislamiento bacteriano. El 100% (96) de las cepas estudiadas fue sensible a penicilina con valores de CIM comprendidos entre 0,012 y 0,094 µg mL-1. Estos resultados indican que penicilina sigue siendo el antimicrobiano de elección durante la profilaxis intraparto, para la prevención de la enfermedad neonatal causada por SGB en nuestra región. Se destaca la importancia de la vigilancia epidemiológica de la sensibilidad a penicilina y a otros antimicrobianos para alertar sobre nuevos mecanismos de resistencia y adecuar estrategias de tratamiento.

Mini-mastoidectomía para anastomosis hipogloso-facial con sección parcial del nervio hipogloso

PubMed Central

Campero, Álvaro; Ajler, Pablo; Socolovsky, Mariano; Martins, Carolina; Rhoton, Albert

2012-01-01

Introducción: La anastomosis hipogloso-facial es la técnica de elección para la reparación de la parálisis facial cuando no se dispone de un cabo proximal sano del nervio facial. La técnica de anastomosis mediante fresado mastoideo y sección parcial del hipogloso minimiza la atrofia lingual sin sacrificar resultados a nivel facial. Método: La porción mastoidea del nervio facial transcurre por la pared anterior de la AM, a un promedio de 18+/-3 mm de profundidad respecto de la pared lateral. Se debe reconocer la cresta supramastoidea, desde la cual se marca una línea vertical paralela al eje mayor de la AM, 1 cm por detrás de la pared posterior del CAE El fresado se comienza desde la línea medio mastoidea hasta la pared posterior del CAE. Una vez encontrado el nervio facial en el tercio medio del canal mastoideo, el mismo es seguido hacia proximal y distal. Resultados: El abordaje descripto permite acceder al nervio facial intratemporal en su porción mastoidea, y efectuar un fresado óseo sin poner en riesgo al nervio o a estructuras vasculares cercanas. Se trata de un procedimiento técnicamente más sencillo que los abordajes amplios habitualmente utilizados al hueso temporal; no obstante su uso debe ser restringido mayormente a la anastomosis hipogloso-facial. Conclusión: Esta es una técnica relativamente sencilla, que puede ser reproducida por cirujanos sin mayor experiencia en el tema, luego de su paso por el laboratorio de anatomía. PMID:23596555

Differences in preeclampsia rates between African American and Caucasian women: trends from the National Hospital Discharge Survey.

PubMed

Breathett, Khadijah; Muhlestein, David; Foraker, Randi; Gulati, Martha

2014-11-01

African Americans are at higher risk for preeclampsia compared with Caucasians, but longitudinal changes are unknown. We hypothesized that preeclampsia rates among African Americans would be higher than that of Caucasians and over time would maintain a consistent divergence. We analyzed the annual prevalence rates and calculated prevalence odds ratios (POR) with 95% confidence intervals (95% CI) for preeclampsia comparing 4,644 African American (weighted 608,109) with 12,131 Caucasian (weighted 1,844,391) women from the National Hospital Discharge Survey (1979-2006), including all women for whom a delivery was associated with preeclampsia. We estimated the race-specific prevalence of preeclampsia while adjusting for age, geographic region, diabetes, essential hypertension, prior myocardial infarction, heart failure, benign essential hypertension complicating a pregnancy, transient hypertension, and gestational diabetes. There was an increasing trend in preeclampsia rates per year from 1979 to 2006 for African Americans [POR 0.76 (95% CI 0.49, 1.03)] and Caucasians [0.29 (95% CI 0.17, 0.41)]. However, there was an initial decrease in prevalence from 1979-1988 among African-Americans [-0.96 (95% CI -1.78, -0.14)] that was not seen in Caucasians [0.12 (95% CI -0.33, 0.57)]. Across all study years, preeclampsia rates remained higher for African Americans compared to Caucasians, from a POR of 0.98 (95% CI 0.96, 1.0) to POR of 1.75 (95% CI 1.73, 1.78). There was an increase in the prevalence of preeclampsia in African Americans compared to Caucasians in the most recent decade under study. This may be explained by healthcare system changes and disparities in obesity. Action is needed to reduce the trajectory of future cardiovascular disease caused by preeclampsia.

High effort, low reward, and cardiovascular risk factors in employed Swedish men and women: baseline results from the WOLF Study

PubMed Central

Peter, R.; Alfredsson, L.; Hammar, N.; Siegrist, J.; Theorell, T.; Westerholm, P.

1998-01-01

STUDY OBJECTIVE: To examine associations between measures of work stress (that is, the combination of high effort and low reward) and cardiovascular risk factors. DESIGN: Cross sectional first screening of a prospective cohort study. SETTING AND PARTICIPANTS: The study was conducted among 5720 healthy employed men and women living in the greater Stockholm area aged 19-70 years. All analyses were restricted to subjects with complete data (n = 4958). The investigation of associations between indicators of effort-reward imbalance and cardiovascular risk factors was restricted to the age group 30-55 years (n = 3427). MAIN RESULTS: Subjects reporting high effort and low reward at work had a higher prevalence of well known risk factors for coronary heart disease. After adjustment for relevant confounders, associations between a measure of extrinsic effort and reward (the effort-reward ratio) and hypertension (multivariate prevalence odds ratio (POR) 1.62- 1.68), increased total cholesterol (upper tertile 220 mg/dl)(POR = 1.24) and the total cholesterol/high density lipoprotein(HDL)- cholesterol ratio (upper tertile 4.61)(POR 1.26-1.30) were found among men. Among women a measure of high intrinsic effort (immersion) was related to increased low density lipoprotein (LDL)-cholesterol (upper tertile 130 mg/dl)(POR 1.37-1.39). Analyses of variance showed increasing mean values of LDL cholesterol with an increasing degree of the effort-reward ratio among men and increased LDL-cholesterol among women with high levels of intrinsic effort (upper tertile of immersion). CONCLUSIONS: Findings lend support to the hypothesis that effort-reward imbalance represents a specific constellation of stressful experience at work related to cardiovascular risk. The relation was not explained by relevant confounders (for example, lack of physical exercise, body weight, cigarette smoking).   PMID:10320854

Prostitution, HIV, and cervical neoplasia: a survey in Spain and Colombia.

PubMed

de Sanjosé, S; Palacio, V; Tafur, L; Vazquez, S; Espitia, V; Vazquez, F; Roman, G; Muñoz, N; Bosch, F X

1993-01-01

The prevalence of cervical intraepithelial neoplasia (CIN) and the association of CIN with prostitution was examined in Oviedo, a region in Spain with low incidence of cervical cancer, and in Cali, Colombia, where the incidence of cervical cancer is 6-10 times higher. In Oviedo, the study included 758 prostitutes attending a sexually transmitted diseases clinic and 1203 nonprostitutes attending a family-planning clinic. In Cali, 775 prostitutes and 1795 nonprostitutes attending health centers were included. Seropositivity to common sexually transmitted agents was investigated in Spanish prostitutes. No significant difference was found in the prevalence of CIN between Oviedo and Cali in both prostitutes (2.5 versus 1.8%) and nonprostitutes (1.2 versus 1.1%). Prostitutes had a 2-fold increased risk of CIN as compared to nonprostitutes; in Spain, the prevalence odds ratio (POR) was 2.3 and the 95% confidence interval (CI) was 1.1-4.5, and, in Colombia, POR was 1.8 and the 95% CI was 0.9-3.5. Among prostitutes in Oviedo, human immunodeficiency virus (HIV) prevalence was 4.9% and HIV-positive prostitutes showed a high risk of CIN as compared to HIV-negative prostitutes (POR, 12.7; 95% CI, 3.9-40.9); 76% of HIV-positive prostitutes were i.v. drug users and showed an increased seroprevalence of other sexually transmitted diseases. HIV-negative prostitutes did not show any increased risk of CIN (POR, 1.2; 95% CI, 0.5-2.8). These results show that among nonprostitutes the prevalence of CIN was not statistically different between the two cities in Spain and Colombia; prostitutes were at moderate increased risk compared to nonprostitutes in both cities.(ABSTRACT TRUNCATED AT 250 WORDS)

Incidence of Cardiac Perforation With Conventional and With Leadless Pacemaker Systems: A Systematic Review and Meta-Analysis.

PubMed

Vamos, Mate; Erath, Julia W; Benz, Alexander P; Bari, Zsolt; Duray, Gabor Z; Hohnloser, Stefan H

2017-03-01

Two leadless pacemaker (PM) systems were recently developed to avoid pocket- and lead-related complications. As leadless PMs are implanted with a large delivery catheter, cardiac perforation remains a major safety concern. We aimed to provide a literature review on incidence of cardiac perforation with conventional and with leadless PM systems. A systematic review over the last 25 years for studies reporting data on PM lead perforation was performed. Findings were synthesized descriptively. Where control groups were available, data were meta-analyzed to identify important clinical risk factors. A total of 28 studies comprising 60,744 patients undergoing conventional PM implantation were analyzed. The incidence of lead perforation ranged from 0% to 6.37% (mean 0.82%, weighted mean 0.31%, median of 0.40%). There was no significant difference in perforation risk between atrial and ventricular electrodes (POR 0.72, 95% confidence interval [CI], 0.28-1.87, P = 0.50) and between MRI conditional and conventional leads (POR 5.93, 95% CI, 0.72-48.76, P = 0.10). The use of active fixation leads (POR 4.25, 95% CI, 1.00-17.95, P = 0.05) and utilization of DDD versus VVI PM systems (POR 3.50, 95% CI, 1.48-8.28, P < 0.01) were associated with higher rates of perforation. In the 2 leadless PM studies, the incidence of cardiac perforation was 1.52% for each. PM lead perforation rates vary in individual studies with an overall low incidence. Leadless PMs seem to be associated with a slightly higher perforation risk, most likely reflecting a learning curve effect of this novel technology. © 2016 Wiley Periodicals, Inc.

Individual and school environment factors associated with overweight in adolescents of the municipality of Rio de Janeiro, Brazil.

PubMed

Cardoso, Letícia de Oliveira; de Castro, Inês Rugani Ribeiro; Gomes, Fabio da Silva; Leite, Iuri da Costa

2011-05-01

To identify the association of individual and school environment factors with overweight among adolescents. Cross-sectional study. Sociodemographic and behavioural information was collected using an anonymous self-administered questionnaire. Indicators on human and physical resources of the schools were based on information collected in interviews with school principals. Overweight was defined based on the BMI Z-score for age and sex recommended by WHO. Logistic regression models were used for statistical analysis. Rio de Janeiro, Brazil. By means of a two-stage (classrooms and students) probabilistic sampling, subjects comprised 1632 students enrolled in the last year of primary education of the municipal public school network, stratified by city region. The mean prevalence of overweight at schools was 17·2%, ranging from 0% to 50%. Adolescents more likely to be overweight were those who attended schools without knives and forks or ceramic/glass plates for students in the school refectory (prevalence odds ratio (POR) = 1·40; P = 0·04), those whose head of household had completed between 8 and 10 years of schooling (POR = 1·46; P = 0·03), those who did not live with both parents (POR = 1·24; P = 0·06) and those who had not practised physical activity outside school on at least 1 d in the 7 d before the study (POR = 1·56; P = 0·04). Sociodemographic and behavioural variables of adolescents and school characteristics were associated with overweight, confirming individual and context effects on this health disorder. Studies such as the present one, identifying variables in context, may support actions to prevent overweight among adolescents.

Progresos recientes en Astronomía de Rayos Gamma

NASA Astrophysics Data System (ADS)

Romero, G. E.

Tras la exitosa misión del Compton Gamma-Ray Observatory durante los años 1990, la astronomía de rayos gamma ha entrado en una etapa de madurez, convirtiéndose en una de las principales herramientas para el estudio de procesos relativistas en el universo. En este reporte, presentaré una revisión de los principales tópicos abordados a través de estudios con rayos gamma en los últimos años, con particular énfasis en los intentos más recientes por establecer la naturaleza de las fuentes de rayos gamma no identificadas, detectadas por el instrumento EGRET.

Aplicación del Teorema de Nekhorochev para tiempos de estabilidad en Mecánica Celeste

NASA Astrophysics Data System (ADS)

Miloni, O.; Núñez, J.; Brunini, A.

En Mecánica Celeste, uno de los problemas centrales consiste en la determinación de los tiempos de estabilidad. El teorema de Nekhorochev proporciona un método para dicho estudio, para un sistema determinado por un hamiltoniano descripto en las variables acción-ángulo. El trabajo consiste en la acotación tanto del potencial perturbador y de la matriz hessiana del hamiltoniano integrable para determinar luego el tiempo de estabilidad de dicho sistema, donde por estabilidad se entiende la separación en norma infinito en el espacio de las acciones.

Analysis by Activation. Part III. Simultaneous Determination of Copper and Uranium in Minerals by Radioactivation; ANALISES POR ATIVACAO. PARTE III. DETERMINACAO SIMULTANEA DE OURO E URANIC NOS MINERAIS POR RADIOATIVACAO

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abrao, A.

1959-04-01

ABS>Copper and uranium frequently associated in the same mineral, can be qualitatively and quantitatlvely determined by means of the radioisotopes Au/sup 198/ and Np/sup 239/ formed during the irradiation of the mineral in a reactor The copper is separated from the neptunium and fission products by anion resin without the addition of isotopic carriers. The efficiency of the chemical separation and the purity of the two radioisotopes is controlled by gamma spectroscopy and bidetermination of the half lives. (tr-auth)

Aquisição fonológica do português brasileiro por crianças ouvintes bilíngues bimodais e surdas usuárias de implante coclear

PubMed Central

Cruz, Carina Rebello; Finger, Ingrid

2014-01-01

Resumo O presente estudo investiga a aquisição fonológica do Português Brasileiro (PB) por 24 crianças ouvintes bilíngues bimodais, com acesso irrestrito à Língua Brasileira de Sinais (Libras), e por 6 crianças surdas que utilizam implante coclear (IC), com acesso restrito ou irrestrito à Libras. Para a avaliação do sistema fonológico das crianças em PB, foi utilizada a Parte A, Prova de Nomeação, do ABFW – Teste de Linguagem Infantil (ANDRADE et al. 2004). Os resultados revelaram que as crianças ouvintes bilíngues bimodais e a criança surda usuária de IC com acesso irrestrito à Libras apresentaram processo de aquisição fonológica esperada (normal) para a sua faixa etária. Considera-se que a aquisição precoce e o acesso irrestrito à Libras podem ter sido determinantes para o desempenho dessas crianças no teste oral utilizado. PMID:25506105

Data Sharing Statements for Clinical Trials: A Requirement of the International Committee of Medical Journal Editors.

PubMed

Taichman, Darren B; Sahni, Peush; Pinborg, Anja; Peiperl, Larry; Laine, Christine; James, Astrid; Hong, Sung-Tae; Haileamlak, Abraham; Gollogly, Laragh; Godlee, Fiona; Frizelle, Franka; Florenzano, Fernando; Drazen, Jeffrey M; Bauchner, Howard; Baethge, Christopher; Backus, Joyce

2017-06-01

El Comité Internacional de Editores de Revista Médicas (ICMJE) ha tomado la posición que el compartir los datos generados por los ensayos clínicos es una obligación ética, por cuanto los participantes en esos estudios se colocaron en riesgo al aceptar su inclusión. En esta editorial el ICMJE expresa que requerirá desde Julio 2018 que los manuscritos enviados a sus revistas deben incluir una declaración sobre compartir datos. A su vez, los ensayos clínicos que comiencen a enrolar pacientes a partir de Enero 2019, deben incluir un plan sobre compartir datos en el registro de tales ensayos. Se dan en esta declaración cuatro ejemplos de declaraciones sobre compartir datos, referidos a qué datos se compartirán, cuándo estarán disponibles y qué criterios de acceso se establecerán. El ICMJE visualiza un futuro cercano en el cual el compartir los datos será la norma, con el fin de maximizar el conocimiento ganado por los esfuerzos y sacrificios de los participantes.

Improved purification of native meningococcal porin PorB and studies on its structure/function.

PubMed

Massari, Paola; King, Carol A; MacLeod, Heather; Wetzler, Lee M

2005-12-01

The outer membrane protein PorB of Neisseria meningitidis is a pore-forming protein which has various effects on eukaryotic cells. It has been shown to (1) up-regulate the surface expression of the co-stimulatory molecule CD86 and of MHC class II (which are TLR2/MyD88 dependent and related to the porin's immune-potentiating ability), (2) be involved in prevention of apoptosis by modulating the mitochondrial membrane potential, and (3) form pores in eukaryotic cells. As an outer membrane protein, its native trimeric form isolation is complicated by its insoluble nature, requiring the presence of detergent throughout the whole procedure, and by its tight association with other outer membrane components, such as neisserial LOS or lipoproteins. In this study, an improved chromatographic purification method to obtain an homogeneous product free of endotoxin and lipoprotein is described, without loss of any of the above-mentioned properties of the porin. Furthermore, we have investigated the requirement of the native trimeric structure for the porin's activity. Inactivation of functional PorB trimers into non-functional monomers was achieved by incubation on ice. Thus, routine long- and medium-term storage at low temperature may be a cause of porin inactivation.

A mechanism of charge transport in electroluminescent structures consisting of porous silicon and single-crystal silicon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Evtukh, A. A., E-mail: dept_5@isp.kiev.ua; Kaganovich, E. B.; Manoilov, E. G.

2006-02-15

Electroluminescent structures that emit in the visible region of the spectrum and are based on porous silicon (por-Si) formed on the p-Si substrate electrolytically using an internal current source are fabricated. The photoluminescent and electroluminescent properties, as well as the current-and capacitance-voltage characteristics of the structures are studied. Electroluminescence is observed only if the forward bias voltage is applied to the structure; the electroluminescence mechanism is based on the injection and is related to the radiative recombination of electrons and holes in quantum-dimensional Si nanocrystals. The injection of holes is controlled by the condition of their accumulation in the space-chargemore » region of p-Si and by a comparatively low concentration of electronic states at the por-Si/p-Si interface. The charge transport in por-Si is caused by the direct tunneling of charge carriers between the quantum-mechanical levels, which is ensured by an appreciable number of quantum-dimensional Si nanocrystals. The leakage currents are low as a result of a small variance in the sizes of Si nanocrystals and the absence of comparatively large nanocrystals.« less

Significance of Algal Polymer in Designing Amphotericin B Nanoparticles

PubMed Central

Bhatia, Saurabh; Kumar, Vikash; Sharma, Kiran; Nagpal, Kalpana; Bera, Tanmoy

2014-01-01

Development of oral amphotericin B (AmB) loaded nanoparticles (NPs) demands a novel technique which reduces its toxicity and other associated problems. Packing of AmB in between two oppositely charged ions by polyelectrolyte complexation technique proved to be a successful strategy. We have developed a novel carrier system in form of polyelectrolyte complex of AmB by using chitosan (CS) and porphyran (POR) as two oppositely charged polymers with TPP as a crosslinking agent. Initially POR was isolated from Porphyra vietnamensis followed by the fact that its alkali induced safe reduction in molecular weight was achieved. Formulation was optimized using three-factor three-level (33) central composite design. High concentration of POR in NPs was confirmed by sulfated polysaccharide (SP) assay. Degradation and dissolution studies suggested the stability of NPs over wide pH range. Hemolytic toxicity data suggested the safety of prepared formulation. In vivo and in vitro antifungal activity demonstrated the high antifungal potential of optimized formulation when compared with standard drug and marketed formulations. Throughout the study TPP addition did not cause any significant changes. Therefore, these experimental oral NPs may represent an interesting carrier system for the delivery of AmB. PMID:25478596

Associations between a voluntary restaurant menu designation initiative and patron purchasing behavior.

PubMed

Sosa, Erica T; Biediger-Friedman, Lesli; Banda, Martha

2014-03-01

Restaurant initiatives provide an efficient opportunity to impact large numbers of patrons. The purpose of this study is to measure patron purchasing behaviors during the ¡Por Vida! menu designation initiative. This study used a cross-sectional design and survey data to assess 23 restaurants throughout Bexar County and 152 restaurant patrons. The Patron Awareness Questionnaire assessed if patrons noticed the logo; believed nutrition, cost, and taste were important in making purchasing decisions; and purchased a ¡Por Vida! item. Descriptive statistics, Spearman correlations, and logistic regression were used to analyze the data. Most (93.4%) patrons considered taste very important when deciding what to eat. Cost was very important to 63.8% and nutrition was very important to 55.9% of the sample. The strongest predictors of purchasing a ¡Por Vida! item were the patrons' ages being between 18 and 35 years (odds ratio = 1.474; confidence interval = 0.017, 0.812; p < .05) and if patrons saw the logo (odds ratio = 4.327; confidence interval = 1.696-11.036; p < .01). Menu logo designation initiatives can potentially influence patron purchasing behaviors among a segment of the population when the logo is visible.

La inserción en el mercado laboral de los inmigrantes latinos en España y en los Estados Unidos: Diferencias por país de origen y estatus legal

PubMed Central

Connor, Phillip; Massey, Douglas

2013-01-01

Resumen Este artículo compara los resultados económicos entre los inmigrantes latinoamericanos en España y Estados Unidos. Detectamos un efecto de selección por el que la mayoría de los inmigrantes latinoamericanos en España proceden de Sudamérica de un entorno de clases medias, mientras la mayoría de los inmigrantes que van a los Estados Unidos son centroamericanos de clase baja. Este efecto de selección explica las diferencias transnacionales en la probabilidad de empleo, logro ocupacional y salarios obtenidos. A pesar de las diferencias en los orígenes y las características de los latinoamericanos en ambos países, los factores demográficos, humanos y de capital social parecen operar de forma similar en ambos países; y cuando los modelos se estiman separadamente por estatus legal, descubrimos que los efectos se acentúan más entre los inmigrantes irregulares cuando se los compara con los regulares, especialmente en Estados Unidos. PMID:24532857

Evolución de estrellas enanas blancas de Helio de masa baja e intermedia

NASA Astrophysics Data System (ADS)

Althaus, L. G.; Benvenuto, O. G.

Numerosas observaciones realizadas particularmente en los últimos dos años parecen confirmar que las enanas blancas (EB) de helio de masa baja e intermedia son el resultado de la evolución de sistemas binarios cercanos. Con el objeto de realizar una adecuada interpretación de estos objetos son necesarios modelos de EBs de helio lo más detallado posibles. En este estudio presentamos cálculos detallados de la evolución de EBs de helio con masas entre M=0.1Msolar y M=0.5Msolar a intervalos de 0.05Msolar . Para ello, hemos tenido en cuenta los efectos de temperatura finita mediante un código de evolución estelar lo más actualizado posible. En particular, el transporte de energía es descripto en el marco del nuevo modelo para la convección turbulenta desarrollado por Canuto - Mazzitelli. Además hemos considerado la nueva ecuación de estado para plasmas de helio de Saumon et al. y nuevas opacidades radiativas OPAL. Las pérdidas por neutrinos fueron asimismo tenidas en cuenta. Excepto para las EBs más masivas, nuestros modelos iniciales están ubicados en las cercanías de la correspondiente línea de Hayashi para configuraciones de helio. Nuestros resultados muestran que existe una región prohibida en el diagrama observacional HR donde ninguna EB de helio puede encontrarse. Dicha región es para log{(L/Lsolar )}>= -0.25 and log{Teff} >= 4.45. Hemos encontrado también que los tracks evolutivos en el diagrama HR en el dominio de alta luminosidad (pre - EB) son fuertemente afectados por la eficiencia convectiva y que las pérdidas por neutrinos son importantes en los modelos más masivos. Finalmente hemos analizado la estructura de la zona convectiva externa encontrando que la teoría de Canuto - Mazzitelli conduce a un perfil convectivo muy diferente del dado por cualquier versión de la popular teoría de la mixing length. Si bién este comportamiento es decisivo en el contexto de las inestabilides pulsacionales, los radios y gravedades superficiales de los modelos no son afectados al incluir la nueva teoría de convección.

Microstructure design of titanate-based electroceramics =

NASA Astrophysics Data System (ADS)

Amaral, Luis Miguel de Almeida

Electrocerâmicos sao uma classe de materiais avancados com propriedades electricas valiosas para aplicacoes. Estas propriedades sao geralmente muito dependentes da microestrutura dos materiais. Portanto, o objectivo geral deste trabalho e investigar o desenho da resposta dielectrica de filmes espessos obtidos por Deposicao Electroforetica (EPD) e cerâmicos monoliticos, atraves do controlo da evolucao da microestrutura durante a sinterizacao de electrocerâmicos a base de titanatos. Aplicacoes sem fios na industria microelectronica e de comunicacoes, em rapido crescimento, tornaram-se um importante mercado para os fabricantes de semicondutores. Devido a constante necessidade de miniaturizacao, reducao de custos e maior funcionalidade e integracao, a tecnologia de filmes espessos esta a tornar-se uma abordagem de processamento de materiais funcionais cada vez mais importante. Uma tecnica adequada neste contexto e EPD. Os filmes espessos resultantes necessitam de um passo subsequente de sinterizacao que e afectada pelo substrato subjacente, tendo este um forte efeito sobre a evolucao da microestrutura. Relacionado com a miniaturizacao e a discriminacao do sinal, materiais dielectricos usados como componentes operando a frequencias das microondas em aplicacoes na industria microelectronica de comunicacoes devem apresentar baixas perdas dielectricas e elevadas permitividade dielectrica e estabilidade com a temperatura. Materiais do sistema BaO-Ln2O3- TiO2 (BLnT: Ln = La ou Nd), como BaLa4Ti4O15 (BLT) e Ba4.5Nd9Ti18O54 (BNT), cumprem esses requisitos e sao interessantes para aplicacoes, por exemplo, em estacoes de base para comunicacoes moveis ou em ressonadores para telefones moveis, onde a miniaturizacao dos dispositivos e muito importante. Por sua vez, o titanato de estroncio (SrTiO3, STO) e um ferroelectrico incipiente com constante dielectrica elevada e baixas perdas, que encontra aplicacao em, por exemplo, condensadores de camada interna, tirando partido de fronteiras de grao altamente resistivas. A dependencia da permitividade dielectrica do campo electrico aplicado torna este material muito interessante para aplicacoes em dispositivos de microondas sintonizaveis. Materiais a base de STO sao tambem interessantes para aplicacoes termoelectricas, que podem contribuir para a reducao da actual dependencia de combustiveis fosseis por meio da geracao de energia a partir de calor desaproveitado. No entanto, as mesmas fronteiras de grao resistivas sao um obstaculo relativamente a eficiencia do STO para aplicacoes termoelectricas. (Abstract shortened by ProQuest.).

Nonthermal Radiation Processes in Interplanetary Plasmas

NASA Astrophysics Data System (ADS)

Chian, A. C. L.

1990-11-01

RESUMEN. En la interacci6n de haces de electrones energeticos con plasmas interplanetarios, se excitan ondas intensas de Langmuir debido a inestabilidad del haz de plasma. Las ondas Langmuir a su vez interaccio nan con fluctuaciones de densidad de baja frecuencia para producir radiaciones. Si la longitud de las ondas de Langmujr exceden las condicio nes del umbral, se puede efectuar la conversi5n de modo no lineal a on- das electromagneticas a traves de inestabilidades parametricas. As se puede excitar en un plasma inestabilidades parametricas electromagneticas impulsadas por ondas intensas de Langmuir: (1) inestabilidades de decaimiento/fusi5n electromagnetica impulsadas por una bomba de Lang- muir que viaja; (2) inestabilidades dobles electromagneticas de decai- miento/fusi5n impulsadas por dos bombas de Langrnuir directamente opues- tas; y (3) inestabilidades de dos corrientes oscilatorias electromagne- ticas impulsadas por dos bombas de Langmuir de corrientes contrarias. Se concluye que las inestabilidades parametricas electromagneticas in- ducidas por las ondas de Langmuir son las fuentes posibles de radiacio- nes no termicas en plasmas interplanetarios. ABSTRACT: Nonthermal radio emissions near the local electron plasma frequency have been detected in various regions of interplanetary plasmas: solar wind, upstream of planetary bow shock, and heliopause. Energetic electron beams accelerated by solar flares, planetary bow shocks, and the terminal shock of heliosphere provide the energy source for these radio emissions. Thus, it is expected that similar nonthermal radiation processes may be responsible for the generation of these radio emissions. As energetic electron beams interact with interplanetary plasmas, intense Langmuir waves are excited due to a beam-plasma instability. The Langmuir waves then interact with low-frequency density fluctuations to produce radiations near the local electron plasma frequency. If Langmuir waves are of sufficiently large amplitude to exceed the thresfiold conditions, nonlinear mode conversion electromagnetic waves can be effected through parametric instabilities. A number of electromagnetic parametric instabilities driven by intense Langmuir waves can be excited in a plasma: (1) electromagnetic decay/fusion instabilities driven by a traveling Langmuir pump; (2) double electromagnetic decay/fusion instabilities driven by two oppositely directed Langmuir pumps; and (3) electromagnetic oscillating two-stream instabilities driven by two counterstreaming Langmuir pumps. It is concluded that the electromagnetic parametric instabilities induced by Langmuir waves are likely sources of nonthermal radiations in interplanetary plasmas. Keq ( : INTERPLANETARY MEDIUM - PLASMAS

Estudo de propriedades estruturais e opticas de multicamadas epitaxiais emissoras de luz baseadas em InGaN/GaN

NASA Astrophysics Data System (ADS)

Pereira, Sergio Manuel de Sousa

Esta tese apresenta os resultados de uma investigacao experimental em filmes epitaxiais emissores de luz baseados em InxGa1-xN. O InxGa1-xN e uma liga semicondutora ternaria do grupo III-N muito utilizada como camada activa numa gama de dispositivos optoelectronicos em desenvolvimento, incluindo diodos emissores de luz (LEDs) e diodos laser (LDs), para operacao na regiao do visivel e ultravioleta do espectro electromagnetico. Neste estudo, caracterizam-se as propriedade opticas e estruturais de camadas simples e pocos quânticos multiplos (Multiple Quantum Wells, MQWs) de InxGa1-xN/GaN, com enfase nas suas propriedades fisicas fundamentais. O objectivo central do trabalho prende-se com a compreensao mais profunda dos processos fisicos que estao por tras das suas propriedades opticas, preenchendo o fosso existente entre aplicacoes tecnologicas e o conhecimento cientifico. Nomeadamente, a tese aborda os problemas da medicao da fraccao de InN (x) em multicamadas ultrafinas sujeitas a tensoes, a influencia da composicao e das tensoes microscopicas nas propriedades opticas e estruturais. A questao relativa a segregacao de fases em multicamadas de InxGa1-xN/GaN e tambem discutida a luz dos resultados obtidos. A metodologia seguida assenta na integracao de resultados obtidos por tecnicas complementares atraves de uma analise sistematica e multidisciplinar. Esta abordagem passa pela combinacao de: 1) Crescimento de amostras por deposicao epitaxial em fase de vapor organometalico (MOVPE) com caracteristicas especificas de forma a tentar isolar parâmetros estruturais, tais como espessura e composicao; 2) Caracterizacao nanoestrutural por microscopia de forca atomica (AFM), microscopica electronica de varrimento (SEM), difraccao de raios-X e retro-dispersao de Rutherford (RBS); 3) Caracterizacao optica a escalas complementares por: espectroscopia de absorcao optica (OA), fotoluminescencia (PL), catodoluminescencia (CL) e microscopia confocal (CM) com analise espectral. Com base nos resultados obtidos, a tese propoe modelos de interpretacao para as propriedades estruturais e opticas, dando enfase as suas correlacoes. Em particular, estabelece-se a necessidade de considerar fenomenos relacionados com tensoes microscopicas na interpretacao dos resultados experimentais. Com este trabalho fica clara a necessidade de um conhecimento detalhado das caracteristicas nanoestruturais para interpretar as propriedades opticas das ligas de InxGa1-xN. None

Caracterización espectroscópica de hielos de interés atmosférico y astrofísico

NASA Astrophysics Data System (ADS)

Escribano, R.

En años recientes se ha incrementado el estudio de procesos físicos y químicos que tienen lugar en la superficie o el interior de hielos, tanto en medios astrofísicos como en la atmósfera terrestre y en otros cuerpos del sistema solar. Se ha comprobado que las partículas heladas actúan como catalizadores de reacciones químicas, que no ocurrirían en su ausencia. En la atmósfera terrestre, es bien conocida la importancia de partículas de hidratos de ácido nítrico, formando las llamadas nubes estratosféricas polares, en los procesos de destrucción de ozono estratosférico. En hielos astrofísicos, átomos como H, C, N y O pueden adherirse o introducirse en la estructura cristalina o amorfa del hielo, y dar lugar a reacciones de formación de moléculas evitando su barrera de activación. Existen partículas heladas en el medio interestelar formando parte de las llamadas nubes moleculares densas y frías, con valores del orden de 106 átomos de H por cm3 y temperaturas entre 3 y 90 K. Alrededor de protoestrellas, pueden formarse hielos de distinta composición, polares o apolares, en las zonas de alejamiento y temperatura decreciente a partir del núcleo caliente. Por su parte, los cometas están formados por un núcleo de hielo y rocas, sobre el que se encuentran adheridas moléculas gaseosas, y una cola, formada por los gases liberados por efecto del calentamiento debido a la radiación solar incidente. En nuestro sistema solar, los polos de La Tierra y de Marte están cubiertos de hielo, así como la mayoría de los cuerpos externos. Los satélites de Júpiter han sido estudiados detalladamente, y se han encontrado en ellos, y en Tritón (satélite de Neptuno), hielos de moléculas como SON2, CO2, N2, CH4 y otros. Para la caracterización espectroscópica de estos hielos se precisan medidas en el laboratorio, aún conociendo la imposibilidad intrínseca de reproducir exactamente las condiciones en que se formaron y se encuentran en los medios astrofísicos. El montaje experimental requiere un sistema que permita alcanzar bajas presiones y temperaturas, formado usualmente por una cámara en cuyo interior se forman películas de hielo de la composición deseada, depositadas sobre un sustrato inerte. Las películas pueden ser a continuación tratadas por diversas técnicas, tales como irradiación UV, bombardeo con electrones o iones, calentamiento y enfriamiento, etc. Habitualmente todos los procesos se controlan por espectroscopía de infrarrojo. La radiación proveniente de un espectrómetro se hace incidir sobre la muestra y se extrae de la cámara mediante ventanas, y se enfoca posteriormente sobre el detector. En el laboratorio de Física Molecular del Instituto de Estructura de la Materia disponemos de un montaje experimental diseñado para el estudio de partículas de hielo similares a las formadas en las nubes estratosféricas polares de nuestra atmósfera. El montaje es similar al descrito anteriormente, excepto en lo que se refiere a las condiciones de presión y temperatura, que son menos estrictas en nuestros experimentos. La extensión de estas condiciones de trabajo a las requeridas en medios astrofísicos es una posibilidad a discutir. Por otra parte, disponemos de un método de cálculo de estructuras periódicas, basado en el programa SIESTA (acrónimo de Spanish Initiative for Electronic Simulations of Thousands of Atoms), que ha proporcionado excelentes resultados en lo relativo a la determinación de estructuras cristalinas y predicción de su espectro infrarrojo, en los sistemas estudiados hasta la fecha, es decir, los hidratos de ácido nítrico de interés atmosféricos. Su aplicación para el estudio de hielos de relevancia astrofísica podría ser del máximo interés.

Microbiological evaluation of the steam sterilization of assembled laparoscopic instruments.

PubMed

Camargo, Tamara Carolina de; Graziano, Kazuko Uchikawa; Almeida, Alda Graciele Claudio Dos Santos; Suzuki, Karina; Silva, Cely Barreto da; Pinto, Flávia Morais Gomes

2016-11-21

assess the safety of steam sterilization of assembled laparoscopic instruments with challenge contamination. a laboratory experimental study, using as test samples trocars and laparoscopic graspers. Geobacillus stearothermophillus ATCC-7953 was used, with a microbial population of 106UFC/Filter paper substrate, removed from the biological indicator. Three of them were introduced into each instrument at the time of assembly, and sterilized at pressurized saturated steam, 134oC for 5 minutes. After sterilization, the instrument was disassembled and each filter paper substrate was inoculated in soybean casein culture and incubated at 56oC for 21 days. In case of absence of growth, they were subjected to heat shock of 80oC, for 20 minutes and re-incubated for 72 hours. Sample size: 185 graspers and 185 trocars, with 95% power. We paired the experiments with comparative negative control groups (5 graspers and 5 trocars with challenge contamination, sterilized disassembled) and positive control (30 filter paper supports, unsterilized), subject to the same incubation procedures. there was no microbial growth in experimental and negative control. The results of the positive control were satisfactory. this study provided strong scientific evidence to support the safety of steam sterilizing of the assembled laparoscopic instrument. avaliar a segurança da esterilização a vapor, do instrumental laparoscópico montado com desafio da contaminação. estudo experimental laboratorial, cujo corpo de prova foram trocarte e pinça laparoscópica. Utilizou-se esporos Geobacillus stearothermophillus ATCC-7953, com população microbiana de 106UFC/suporte de papel filtro, removidos do indicador biológico. Três deles foram introduzidos no interior de cada instrumento, no momento da montagem, sendo esterilizados a vapor saturado sob pressão, 134oC por 5 minutos. Depois da esterilização, o instrumental foi desmontado, e cada suporte de papel filtro foi inoculado em meio de cultura de caseína soja, incubado a 56oC por 21 dias. Não havendo crescimento, foram submetidos a um choque térmico de 80oC, por 20 minutos e reincubados por 72 horas. Tamanho da amostra, 185 pinças e 185 trocartes, com poder de 95%. Os experimentos foram acompanhados dos grupos controle negativo comparativo (5 pinças e 5 trocartes com contaminação desafio, esterilizados desmontados) e positivo (30 suportes de papel filtro, não esterilizados), submetidos aos mesmos procedimentos de incubação. não houve nenhum crescimento microbiano nos grupos experimental e controle negativo. Os resultados do controle positivo foram satisfatórios. este estudo forneceu fortes evidências científicas para sustentar a segurança da prática de esterilização a vapor do instrumental laparoscópico montado. evaluar la seguridad de la esterilización a través de vapor, de instrumental laparoscópico previamente montado con desafío de contaminación. estudio experimental en laboratorio, cuyo cuerpo de prueba fueron trócarte y pinza laparoscópica. Se utilizó esporas Geobacillus stearothermophilus ATCC-7953, con población microbiana de 106UFC/soporte de papel filtro, removidos del indicador biológico. Tres de ellos fueron introducidos en el interior de cada instrumento, en el momento del montaje, los que fueron esterilizados a vapor saturado bajo presión, 134oC por 5 minutos. Después de la esterilización, el instrumental fue desmontado y cada soporte de papel filtro fue inoculado en medio de una cultura de caseína y soya, incubado a 56oC por 21 días. No habiendo crecimiento, fueron sometidos a un choque térmico de 80oC, por 20 minutos y nuevamente incubados por 72 horas. La muestra estuvo constituida por 185 pinzas y 185 trócartes, con poder de 95%. Los experimentos fueron acompañados en los grupos: control negativo comparativo (5 pinzas y 5 trócartes con contaminación desafío, esterilizados desmontados) y positivo (30 soportes de papel filtro, no esterilizados), sometidos a los mismos procedimientos de incubación. no se encontró crecimiento microbiano en los grupos experimental y control negativo. Los resultados del control positivo fueron satisfactorios. este estudio suministra fuertes evidencias científicas para sustentar que la práctica, de esterilización a vapor del instrumental laparoscópico montado, es segura.

Dose-effect relationships between manganese exposure and neurological, neuropsychological and pulmonary function in confined space bridge welders.

PubMed

Bowler, Rosemarie M; Roels, Harry A; Nakagawa, Sanae; Drezgic, Marija; Diamond, Emily; Park, Robert; Koller, William; Bowler, Russell P; Mergler, Donna; Bouchard, Maryse; Smith, Donald; Gwiazda, Roberto; Doty, Richard L

2007-03-01

Although adverse neuropsychological and neurological health effects are well known among workers with high manganese (Mn) exposures in mining, ore-processing and ferroalloy production, the risks among welders with lower exposures are less well understood. Confined space welding in construction of a new span of the San Francisco-Oakland Bay Bridge without adequate protection was studied using a multidisciplinary method to identify the dose-effect relationship between adverse health effects and Mn in air or whole blood. Bridge welders (n = 43) with little or no personal protection equipment and exposed to a welding fume containing Mn, were administered neurological, neuropsychological, neurophysiological and pulmonary tests. Outcome variables were analysed in relation to whole blood Mn (MnB) and a Cumulative Exposure Index (CEI) based on Mn-air, duration and type of welding. Welders performed a mean of 16.5 months of welding on the bridge, were on average 43.8 years of age and had on average 12.6 years of education. The mean time weighted average of Mn-air ranged from 0.11-0.46 mg/m(3) (55% >0.20 mg/m(3)). MnB >10 microg/l was found in 43% of the workers, but the concentrations of Mn in urine, lead in blood and copper and iron in plasma were normal. Forced expiratory volume at 1s: forced vital capacity ratios (FEV(1)/FVC) were found to be abnormal in 33.3% of the welders after about 1.5 years of welding at the bridge. Mean scores of bradykinesia and Unified Parkinson Disease Rating Scale exceeded 4 and 6, respectively. Computer assisted tremor analysis system hand tremor and body sway tests, and University of Pennsylvania Smell Identification Test showed impairment in 38.5/61.5, 51.4 and 88% of the welders, respectively. Significant inverse dose-effect relationships with CEI and/or MnB were found for IQ (p

Modelo analítico del efecto de PRS sobre satélites GPS

NASA Astrophysics Data System (ADS)

Meza, A.; Brunini, C.; Usandivaras, J. C.

El sistema GPS (Global Position System) es, hoy en día, la herramienta de navegación y posicionamiento más potente y lo será sin duda en la próxima década. Gran parte de su valiosa utilidad se debe a la alta precisión que permite lograr y ésta, a su vez, depende, entre otras causas, de la precisión con que se conocen las órbitas de los satélites. La presión de radiación solar (PRS) fija el límite de la precisión con que pueden calcularse en la actualidad las efemérides satelitarias. El objetivo de este trabajo es proponer una mejor resolución de este fenómeno. El modelo analítico aquí presentado, se basa en el análisis del comportamiento de los residuos de un ajuste por mínimos cuadrados en el que se utiliza el modelo de PRS propuesto por Beutler. El mismo consiste en un modelo determinista del fenómeno con dos parámetros libres. Los resultados obtenidos ponen de manifiesto que, aún después de aplicar dichos parámetros, prevalecen en los residuos efectos semidiurnos en las componentes radial,tangencial y normal. Estos resultados obtenidos se comparan con los de un trabajo desarrollado por el Instituto de Berne (Beutler et al., 1994), en el que se utilizaron como pseudo-observaciones las órbitas precisas del IGS (CODE). El intervalo de integración escogido por este centro fueron las semanas 680 y 681. En resumen se tienen arcos de 14 días para todos los satélites, donde las efemérides precisas de los mismos para los 14 días fueron utilizados como pseudo-observaciones. El modelo de fuerza que empleó dicho centro fue básicamente el tradicional en lo que respecta al modelo de las fuerzas gravitacionales, y para la PRS utilizo el modelo standard de Beutler. Los parámetros de este modelo junto con las 6 condiciones iniciales (posición y velocidad) fueron ajustados por el método general de mínimos cuadrados. Los residuos en la componente radial, tangencial y normal, para los satélites con un buen comportamiento, presentan una componente semidiurna. El modelo analítico planteado en este trabajo, predice el comportamiento de los residuos que se observan en las publicaciones más recientes. Esto abre el camino para plantear una estimación distinta de las incógnitas del problema, basado en el método de colocación por mínimos cuadrados. Ello requiere modelar estadísticamente la señal debida a las componentes de la PRS que no son tomadas en cuenta en el modelo determinista.

A protocol for storage and long-distance shipment of Mediterranean fruit fly (Diptera: Tephritidae) eggs. 1. Effect of temperature, embryo age , and storage time on survival and quality

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caceres, C.; Wornoayporn, V.; Islam, S.M.

The operational use of Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann), genetic sexing strains in Sterile Insect Technique applications can be maximized by developing methods for effective shipment of eggs. This would enable a central production facility to maintain the relevant mother stocks and large colonies to supply eggs to satellite centers that would mass produce only males for irradiation and release. In order to achieve this, the survival of medfly embryos of different ages was assessed after storage at 5, 10, 15, 20, and 25 deg. C in water for different periods of time. Survival was affected by allmore » 3 variables, i.e., embryo age, water temperature, and length of storage. Storage of embryos at any temperature for 120 h resulted in almost no survival. Controlling the age of the embryo at the time of the temperature treatment is crucial for the success of this procedure. Embryos collected between 0 to 12 h after oviposition and pre-incubated at 25 deg. C for 12 h provide a suitable 72 h window for shipment when maintained between 10 to 15 deg. C. Under these conditions, no significant reductions in survival during all the developmental stages were observed. (author) [Spanish] El uso operacional de cepas de la mosca del mediterraneo Ceratitis capitata (Wiedemann) en las cuales es posible separar los sexos a traves de mecanismos geneticos para su utilizacion en la Tecnica del Insecto Esteril (TIE), puede ser maximizado con el desarrollo de metodos efectivos para el envio y transporte de huevos. Esto permite que un laboratorio de produccion centralizada mantenga las respectivas colonias responsables por la produccion de huevos para este abastecer laboratorios satelites responsables por la produccion masiva de solamente machos para subsiguiente irradiacion y liberacion. Para ser posible esta alternativa fue evaluada la supervivencia de embriones de diferentes edades despues de su almacenamiento en agua a 5, 10, 15, 20 y 25 deg. C por diferentes periodos de tiempo. La supervivencia fue afectada por las 3 variables evaluadas, la edad del embrion, la temperatura del agua y el periodo de almacenamiento. El almacenamiento de los embriones a cualquier temperatura por 120 horas dio como resultado la casi no supervivencia. Una edad controlada de los embriones a tratar es crucial para el exito de este protocolo. Embriones colectados entre 0 a 12 horas despues de la oviposicion y su previa incubacion a 25 deg. C por 12 horas brinda un margen de hasta de 72 horas de duracion del almacenamiento y transporte, siempre y cuando estos se mantengan en una temperatura de entre 10 a 15{sup o}C. En estas condiciones, fue registrada una reduccion no significante de la supervivencia de los diferentes estados de desarrollo. (author)« less

Generacion de Nuevas Capacidades en el Ejercito de Guatemala para el Combate al Trafico de Drogas y Delitos Conexos (Generating New Capacities within the Guatemalan Army in Order to Combat Drug Trafficking and Related Crimes)

DTIC Science & Technology

2014-06-13

la pérdida de control territorial por parte del Estado en el tema de seguridad y la poca credibilidad que la sociedad tiene en sus fuerzas...de seguridad civil y segundo: como efecto no buscado de la presión ejercida por el gobierno de Colombia y el de México en alianza con los Estados...naturales y líneas rectas que unen detalles topográficos fijados y descritos en el mismo Laudo. Para la defensa de la seguridad nacional, el Ejército

Estudio de los Efectos Gravitomagnéticos en Cuerpos Masivos Rotantes

NASA Astrophysics Data System (ADS)

Velandia Heredia, N.; Tejeiro, J. M.

2008-03-01

A partir del estudio de los Efectos Gravitomagnéticos en cuerpos masivos rotantes, planteamos la expresión para medir el desfase en el tiempo, para diferentes observadores, que se dan cuando viajan dos rayos de luz por una guía de onda o de manera libre (geodésicas), en el plano azimutal y en el plano polar. Con lo anterior queremos abordar el experimento tipo Michelson y Morley, de forma que podamos involucrar el valor de la densidad del momento angular (a) en el retraso temporal para los dos haces de luz que viajan por los brazos del interferómetro, cuando este último es ubicado en el plano ecuatorial.

Uso de curativo a vácuo como terapia adjuvante na cicatrização de sítio cirúrgico infectado

PubMed Central

de Camargo, Paula Angeleli Bueno; Bertanha, Matheus; Moura, Regina; Jaldin, Rodrigo Gibin; Yoshida, Ricardo de Alvarenga; Pimenta, Rafael Elias Farres; Mariúba, Jamil Victor de Oliveira; Sobreira, Marcone Lima

2016-01-01

Resumo Infecções de sítios cirúrgicos com envolvimento de próteses sintéticas constituem grande desafio para tratamento. Apresentamos o caso de uma paciente com múltiplas comorbidades, histórico de enxerto aortobifemoral há 6 anos e reabordagem das anastomoses femorais por reestenoses há 5 anos. Apresentou dor inguinal esquerda e abaulamento súbitos com diagnóstico de pseudoaneurisma femoral roto e instabilidade hemodinâmica. Foi submetida a correção emergencial com interposição de prótese de dácron recoberta por prata e correção de grande hérnia incisional abdominal com tela sintética ao mesmo tempo. No pós-operatório, manteve-se por longo período sob terapia intensiva com dificuldade de extubação. Nesse ínterim, apresentou deiscência das suturas e fístula purulenta inguinal esquerda em contato com a prótese vascular. Optou-se pelo tratamento conservador, com desbridamento das feridas e aplicação de curativo a vácuo. A paciente evoluiu com melhora e cicatrização das feridas. Essa pode se constituir em ferramenta importante em casos similares.

Regulación del flujo sanguíneo uterino. II. Funciones de estrógeno y receptores estrogénicos α/β en acciones genómicas y no-genómicas del endotelio uterino *

PubMed Central

Mayra, Pastore R.; Rosalina, Villalón L.; López, Gladys; Iruretagoyena, Jesús; Magness, Ronald

2015-01-01

Resumen El embarazo está marcado por cambios y adaptaciones cardiovasculares que son importantes para el crecimiento y mantenimiento de la placenta y el feto. Durante este periodo, las adaptaciones vasculares uterinas manifiestan cambios clasificados como de corto o largo plazo los cuales están relacionados con adaptaciones vasodilatadoras, angiogénicas o de remodelación. El estrógeno y los receptores estrogénicos clásicos (REs), RE-α y RE-β, han demostrado ser parcialmente responsables por facilitar el incremento dramático en el fluido sanguíneo uterino necesario durante el embarazo. En ésta revisión bibliográfica se discuten la base estructural para la diversidad y selectividad funcional de los REs por el estrógeno, el papel de los REs sobre los efectos genómicos y no-genómicos en células endoteliales de arterias uterinas (CEAU). Estos temas integran el conocimiento científico sobre la regulación molecular de CEAU para mantener el incremento fisiológico en la perfusión útero-placentaria observada durante un embarazo normal. PMID:26113751

Actitudes Éticas de los estudiantes y egresados en carrera de medicina con metodologías activas

PubMed Central

Novaes, Maria Rita Carvalho Garbi; Novaes, Luiz Carlos Garcez; Guilhem, Dirce; Stepke, Fernando Lolas; Silveira, Carla Cristina Costa; Komatsu, Ricardo Shoiti; Trindade, Eliane Mendonça Vilar; Guiotti, Murilo Galvão

2010-01-01

El presente estudio tiene por objeto desarrollar un diagnostico de la inserción integrada de la ética en la carrera de medicina brasileña con una metodología de aprendizaje basada en problemas y describir las percepciones de actitudes éticas de los estudiantes y egresados. El diseño metodológico es un estudio de caso, descriptivo y documental, con abordaje cualitativo y cuantitativo. La muestra de esta investigación ha sido constituida por 120 estudiantes y 40 egresados de dos promociones del Curso de Medicina de la ESCS. Este proyecto fue aprobado por el Comité de Ética en Investigación - SES/DF. Los estudiantes y egresados de la ESCS demostraron un buen manejo en el abordaje de los conflictos éticos y respeto a los pacientes. Sin embargo, el análisis de sensibilidad ética mostró una fragilidad en las percepciones y aptitudes inapropiadas de los estudiantes de la carrera de medicina, identificada básicamente en los años iniciales, que necesitan más discusiones sistematizadas sobre los aspectos éticos y bioéticos integrados a las actividades prácticas para estimular y fortalecer la reflexión ética de los estudiantes. PMID:20981242