Horizontal and vertical transmissions in the US oil supply chain

International Nuclear Information System (INIS)

Kaufmann, Robert K.; Dees, Stephane; Mann, Micheal

2009-01-01

Oil prices, inventory levels, and utilization rates are influenced by changes that are transmitted horizontally and/or vertically through the energy supply chain. We define horizontal transmissions as changes that are generated by linkages among fuels at a similar stage of processing while vertical transmissions are changes that are generated by upstream/downstream linkages in the oil supply chain. Here, we investigate vertical and horizontal transmissions by estimating vector error correction models (VECMs) that represent relationships among the price of crude oil, US refinery utilization rates, US stocks of crude oil, US stocks of motor gasoline, the US price of motor gasoline, and the US price of a substitute fuel, natural gas. Causal relationships estimated from both weekly and quarterly observations indicate that the price of crude oil is an important gateway for disturbances to the oil supply chain. Impulse response functions indicate that disturbances to crude oil prices ripple down the oil supply chain and affect inventory behaviors, refinery utilization rates, and the price of motor gasoline, and are transmitted laterally to the natural gas market. (author)

First record of natural vertical transmission of dengue virus in Aedes aegypti from Cuba.

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Gutiérrez-Bugallo, Gladys; Rodriguez-Roche, Rosmari; Díaz, Gisell; Vázquez, Antonio A; Alvarez, Mayling; Rodríguez, Magdalena; Bisset, Juan A; Guzman, Maria G

2017-10-01

While horizontal transmission (human-mosquito-human) of dengue viruses largely determines the epidemiology of the disease, vertical transmission (infected female mosquito- infected offspring) has been suggested as a mechanism that ensures maintenance of the virus during adverse conditions for horizontal transmission to occur. The purpose of this study was to analyze the natural infection of larval stages of Aedes aegypti (Diptera: Culicidae) with the dengue virus (DENV) in Cuba. Here, we report vertical transmission of DENV-3 genotype III in natural populations of Ae. aegypti through RT-PCR detection and serotyping plus sequencing. Our report constitutes the first record of vertical transmission of DENV in Ae. aegypti from Cuba with details of its serotype and genotype. Copyright © 2017 Elsevier B.V. All rights reserved.

Intensification of antiretroviral treatment with raltegravir for pregnant women living with HIV at high risk of vertical transmission.

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Puthanakit, Thanyawee; Thepnarong, Nattawan; Chaithongwongwatthana, Surasith; Anugulruengkitt, Suvaporn; Anunsittichai, Orawan; Theerawit, Tuangtip; Ubolyam, Sasiwimol; Pancharoen, Chitsanu; Phanuphak, Praphan

2018-04-01

Objectives:  The rate of vertical HIV transmission for women at high risk of HIV transmission stands at approximately 7.6%. In the present study we describe infant infection rates in women who had received raltegravir (RAL) intensification during pregnancy to a standard three-drug antiretroviral (ART) regimen in Thailand. Methods:  This prospective cohort study enrolled HIV-1-positive pregnant women at high risk of vertical transmission, as defined by (1) ART initiation at a gestational age (GA) ≥32 weeks or (2) HIV-1 RNA >1000 copies/mL at GA of 32-38 weeks while on ART. Women received a standard three-drug ART regimen with RAL intensification (400 mg twice daily) until delivery and continued on a three-drug ART regimen after delivery. Plasma HIV-1 RNA testing was performed before intensification and at delivery. Infant HIV-1 status was determined using DNA PCR at birth, and at 1, 2 and 4 months of life. Results:  Between February 2016 and November 2017, 154 pregnant women on ART were enrolled into the study with a median CD4 cell count and plasma HIV-1 RNA level of 382 cells/mm 3 and 4.0 log 10 copies/mL, respectively. The three-drug combination consisted of either a lopinavir/ritonavir- (53%) or efavirenz-based (43%) regimen. Median GA at time of RAL initiation was 34 weeks (interquartile range [IQR] 33-36) and median duration was 21 days (IQR 8-34). The proportion of women who had a plasma HIV-1 RNA HIV infection, three in utero and three peripartum. Overall vertical transmission rate was 3.9% (95% confidence interval [CI] 1.4-8.2). Conclusion:  The majority of high-risk pregnant women living with HIV-1 who had received RAL intensification achieved viral suppression at delivery with a relatively low rate of vertical transmission. This intensification strategy represents an option for prevention in HIV-positive women at high risk of vertical transmission.

Invasion fitness for gene-culture co-evolution in family-structured populations and an application to cumulative culture under vertical transmission.

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Mullon, Charles; Lehmann, Laurent

2017-08-01

Human evolution depends on the co-evolution between genetically determined behaviors and socially transmitted information. Although vertical transmission of cultural information from parent to offspring is common in hominins, its effects on cumulative cultural evolution are not fully understood. Here, we investigate gene-culture co-evolution in a family-structured population by studying the invasion fitness of a mutant allele that influences a deterministic level of cultural information (e.g., amount of knowledge or skill) to which diploid carriers of the mutant are exposed in subsequent generations. We show that the selection gradient on such a mutant, and the concomitant level of cultural information it generates, can be evaluated analytically under the assumption that the cultural dynamic has a single attractor point, thereby making gene-culture co-evolution in family-structured populations with multigenerational effects mathematically tractable. We apply our result to study how genetically determined phenotypes of individual and social learning co-evolve with the level of adaptive information they generate under vertical transmission. We find that vertical transmission increases adaptive information due to kin selection effects, but when information is transmitted as efficiently between family members as between unrelated individuals, this increase is moderate in diploids. By contrast, we show that the way resource allocation into learning trades off with allocation into reproduction (the "learning-reproduction trade-off") significantly influences levels of adaptive information. We also show that vertical transmission prevents evolutionary branching and may therefore play a qualitative role in gene-culture co-evolutionary dynamics. More generally, our analysis of selection suggests that vertical transmission can significantly increase levels of adaptive information under the biologically plausible condition that information transmission between relatives is

Transmissão vertical do HIV: situação encontrada em uma maternidade de Teresina Transmisión vertical del HIV: situación encontrada en una maternidade de Teresina Vertical transmission of HIV: situation found in a maternity of Teresina

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Liliam Mendes de Araújo

2007-08-01

prevent the vertical transmission of HIV in maternity houses of Teresina-PI. The theoretical-methodological approach included the study of organizational dynamics and its actors, by means of qualitative approach. In order to obtain data, 17 semi-structured interviews were carried out. The results revealed that the recommendations of the Ministry of Health were totally followed, making more evident the weakness of the assistance provided, to the mother/son binomial.

Barriers to uptake of prevention of mother-to-child transmission of HIV services among mothers of vertically infected HIV-seropositive infants in Makurdi, Nigeria

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Anígilájé EA

2016-01-01

Full Text Available Emmanuel Ademola Anígilájé,1 Bem Ruben Ageda,2 Nnamdi Okechukwu Nweke1 1Department of Paediatrics, 2Department of Obstetrics and Gynaecology, Federal Medical Centre, Makurdi, Nigeria Background: Perinatal transmission of human immunodeficiency virus (HIV continues in Nigeria because of the poor use of prevention of mother-to-child transmission of HIV (PMTCT services. This study reports on the barriers preventing mothers of vertically infected HIV-seropositive infants to use the PMTCT services at the Federal Medical Centre, Makurdi, Nigeria.Methods: This is a descriptive study conducted between January and April, 2014. A quantitative survey was applied to detect barriers along the PMTCT services cascade among 52 mothers of vertically infected HIV-seropositive infants. This includes 22 women who attended antenatal care at the Federal Medical Centre (designated as Group A mothers and 30 women who did not receive any form of PMTCT service (Group B mothers. The study was supplemented with a focused group discussion involving 12 discussants from the two groups.Results: In the quantitative assessment: among the Group A mothers, falling asleep was the most common reason (n=22, 100% for missing therapeutic/prophylactic antiretroviral medicine; financial constraint (n=22, 100% was the most common reason for antenatal care visit defaults; and a lot of the mothers (n=11, 50.0% did not give nevirapine to their newborns because they delivered at home. Among Group B mothers, unawareness of HIV-seropositive status was the most common reason (n=28, 93.3% given for not accessing PMTCT services. In the qualitative study: noninvolvement of male partners, stigma and discrimination experienced by HIV-seropositive mothers, financial constraints in couples, involvement of traditional birth attendants in antenatal care and delivery of HIV-infected women, unawareness of HIV-seropositive status by pregnant women, poor health system, and the lack of funding for PMTCT

Comparative vertical transmission of Rickettsia by Dermacentor variabilis and Amblyomma maculatum.

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Harris, Emma K; Verhoeve, Victoria I; Banajee, Kaikhushroo H; Macaluso, Jacqueline A; Azad, Abdu F; Macaluso, Kevin R

2017-06-01

The geographical overlap of multiple Rickettsia and tick species coincides with the molecular detection of a variety of rickettsial agents in what may be novel tick hosts. However, little is known concerning transmissibility of rickettsial species by various tick hosts. To examine the vertical transmission potential between select tick and rickettsial species, two sympatric species of ticks, Dermacentor variabilis and Amblyomma maculatum, were exposed to five different rickettsial species, including Rickettsia rickettsii, Rickettsia parkeri, Rickettsia montanensis, Rickettsia amblyommatis, or flea-borne Rickettsia felis. Fitness-related metrics including engorgement weight, egg production index, nutrient index, and egg hatch percentage were then assessed. Subsamples of egg clutches and unfed larvae, nymphs, and adults for each cohort were assessed for transovarial and transstadial transmission of rickettsiae by qPCR. Rickettsial exposure had a minimal fitness effect in D. variabilis and transovarial transmission was observed for all groups except R. rickettsii. In contrast, rickettsial exposure negatively influenced A. maculatum fitness and transovarial transmission of rickettsiae was demonstrated only for R. amblyommatis- and R. parkeri-exposed ticks. Sustained maintenance of rickettsiae via transstadial transmission was diminished from F 1 larvae to F 1 adults in both tick species. The findings of this study suggest transovarial transmission specificity may not be tick species dependent, and sustained vertical transmission is not common. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

Prevención de la transmisión vertical del VIH-1 en un hospital público de complejidad terciaria de Buenos Aires, Argentina Prevention of vertical HIV-1 transmission in a tertiary care public hospital in Buenos Aires, Argentina

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Diego Cecchini

2011-09-01

Full Text Available OBJETIVO: Describir las características de los binomios madre-hijo, la profilaxis antirretroviral, la evolución temporal de la transmisión vertical del VIH-1 y sus variables asociadas en una población asistida por un hospital público de complejidad terciaria de Argentina. MÉTODOS: Estudio descriptivo prospectivo desarrollado por el Grupo de trabajo en prevención de la Transmisión Vertical del Hospital General de Agudos Dr. Cosme Argerich, Buenos Aires, Argentina, entre 1998 y 2008. Se compararon los períodos 1998-2003 y 2004-2008, y se identificaron las variables asociadas a esta vía de contagio. RESULTADOS: De 357 binomios madre-hijo, 21,0% de las madres presentaron coinfección con el virus de la hepatitis C y 68,0% linfocitos CD4 OBJECTIVE: To describe characteristics of mother-child binomium (MCB, antiretroviral (ARV prophylaxis, time trends, and variables associated with vertical transmission of HIV-1 in a population assisted by a tertiary public hospital in Argentina. METHODS: Prospective descriptive study undertaken by the Hospital Cosme Argerich s Vertical Transmission Working Group, Buenos Aires city, Argentina 1998-2008. Periods 1998-2003 vs. 2004-2008 were compared and variables associated with vertical transmission identified. RESULTS: Of 357 MCB, 21.0% of the mothers had HCV coinfection and 68.0% CD4 < 500/µL. During pregnancy, 75.0% received ARV: zidovudine (17.8%, zidovudinelamivudine (19.8%, zidovudine-lamivudine-nevirapine (41.9%, and zidovudinelamivudine-protease inhibitor (11.4%; 74.0% had viral load (VL peripartum < 1 000 copies/mL. Caesarean delivery: 58.0%. Intrapartum zidovudine: 83.4%; 98.0% of infants received prophylaxis; zidovudine monotherapy was the most frequently used (73.0%. Of neonates, 15.4% had low birthweight and 6.7% were premature. The global vertical transmission was 3.3% (10/302. Comparing both periods, an increase in triple ARV and VL < 1 000 copies/mL in peripartum and a decrease in the

Successful prevention of HIV transmission from mother to infant in Brazil using a multidisciplinary team approach

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Susie A. Nogueira

Full Text Available OBJECTIVES: To determine the HIV vertical transmission rate (VTR and associated risk factors by use of zidovudine and infant care education in Brazil. METHODS: Since 1995, a prospective cohort of HIV infected pregnant women has been followed at the Federal University of Rio de Janeiro. A multidisciplinary team was established to implement the best available strategy to prevent maternal-infant HIV transmission. Patients with AIDS or low CD4 and high viral load received anti-retroviral drugs in addition to zidovudine. Children were considered infected if they had 2 positive PCR-RNA tests between 1 and 4 months of age, or were HIV antibody positive after 18 months. Education regarding infant treatment and use of formula instead of breast feeding was provided. RESULTS: Between 1995 and August, 2000, HIV status was determined for 145 infants. Compliance with intra-partum treatment, infant treatment and use of formula was 88.2%. Intra-partum zidovudine treatment was completed in 134/145 (92.6% of patients; 88.1% had rupture of membranes 4 hours were associated with increased HIV transmission. CONCLUSION: HIV vertical transmission in Brazil was reduced to a level similar to other countries with the most effective prevention programs using a multidisciplinary team approach. A high level of compliance for use of anti-retroviral drugs, the provision of health education to mothers, and use of formula for all exposed infants.

Successful prevention of HIV transmission from mother to infant in Brazil using a multidisciplinary team approach

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Nogueira Susie A.

2001-01-01

Full Text Available OBJECTIVES: To determine the HIV vertical transmission rate (VTR and associated risk factors by use of zidovudine and infant care education in Brazil. METHODS: Since 1995, a prospective cohort of HIV infected pregnant women has been followed at the Federal University of Rio de Janeiro. A multidisciplinary team was established to implement the best available strategy to prevent maternal-infant HIV transmission. Patients with AIDS or low CD4 and high viral load received anti-retroviral drugs in addition to zidovudine. Children were considered infected if they had 2 positive PCR-RNA tests between 1 and 4 months of age, or were HIV antibody positive after 18 months. Education regarding infant treatment and use of formula instead of breast feeding was provided. RESULTS: Between 1995 and August, 2000, HIV status was determined for 145 infants. Compliance with intra-partum treatment, infant treatment and use of formula was 88.2%. Intra-partum zidovudine treatment was completed in 134/145 (92.6% of patients; 88.1% had rupture of membranes 4 hours were associated with increased HIV transmission. CONCLUSION: HIV vertical transmission in Brazil was reduced to a level similar to other countries with the most effective prevention programs using a multidisciplinary team approach. A high level of compliance for use of anti-retroviral drugs, the provision of health education to mothers, and use of formula for all exposed infants.

Lousy mums: patterns of vertical transmission of an amphibious louse.

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Leonardi, M S; Crespo, E A; Raga, J A; Aznar, F J

2013-09-01

In this study, we document patterns of vertical transmission of the amphibious louse Antarctophthirus microchir (Echinophthiriidae) in pups of South American sea lion, Otaria flavescens, from Patagonia. Vertical transmission is fundamental for the long-term stability of A. microchir populations because only pups stay long enough (1 month) on land for the louse to reproduce. A total of 72 pups ≤7 days old from a single rookery were captured and examined for lice. Infection parameters and population structure of A. microchir did not differ among pups collected at the beginning, middle, and end of the reproductive season, suggesting that patterns of early vertical transmission are not affected by the increase of rookery size during this period. Over 60% of 1-day-old pups were infected with A. microchir, and recruitment increased in pups up to 3 days old and then leveled off. In 1-day-old pups, significantly more adults than nymphs were found, but the pattern was reversed in older pups. The number of first-stage nymphs was significantly smaller than that of second- and third-stage nymphs, as it was the number of males vs. females, particularly in 1-day-old pups. Three non-exclusive hypotheses could account for these patterns, i.e., recruitment merely reflects the population structure of A. microchir is cows; the relative ability of lice to pass from cows onto pups increases in advanced instars; and/or natural selection favors transmission of adults, especially females, because they accrue greater fitness. The importance of latter hypothesis should not be underestimated in a species with a tight reproductive schedule.

Lack of evidence for vertical transmission of Campylobacter spp. in chickens.

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Callicott, Kenneth A; Friethriksdóttir, Vala; Reiersen, Jarle; Lowman, Ruff; Bisaillon, Jean-Robert; Gunnarsson, Eggert; Berndtson, Eva; Hiett, Kelli L; Needleman, David S; Stern, Norman J

2006-09-01

Campylobacter jejuni is a major cause of bacterial food-borne infection in the industrial world. There is evidence that C. jejuni is present in eggs and hatchery fluff, opening the possibility for vertical transmission from hens to progeny. Poultry operations in Iceland provide an excellent opportunity to study this possibility, since breeding flocks are established solely from eggs imported from grandparent flocks in Sweden. This leaves limited opportunity for grandparents and their progeny to share isolates through horizontal transmission. While Campylobacter was not detected in all grandparent flocks, 13 of the 16 egg import lots consisted of eggs gathered from one or more Campylobacter-positive grandparent flocks. No evidence of Campylobacter was found by PCR in any of the 10 relevant quarantine hatchery fluff samples examined, and no Campylobacter was isolated from the parent birds through 8 weeks, while they were still in quarantine rearing facilities. After the birds were moved to less biosecure rearing facilities, Campylobacter was isolated, and 29 alleles were observed among the 224 isolates studied. While three alleles were found in both Sweden and Iceland, in no case was the same allele found both in a particular grandparent flock and in its progeny. We could find no evidence for vertical transmission of Campylobacter to the approximately 60,000 progeny parent breeders that were hatched from eggs coming from Campylobacter-positive grandparent flocks. If vertical transmission is occurring, it is not a significant source for the contamination of chicken flocks with Campylobacter spp.

Transmission of vertical stress in a real soil profile. Part III

DEFF Research Database (Denmark)

Lamandé, Mathieu; Schjønning, Per

2011-01-01

The transmission of stress in soils is extremely sensitive to changes in water content. According to the elasticity theory, for a given load applied to a given soil, an increase in soil water content yields a higher concentration of stresses under the centre of the load and a deeper propagation...... of stresses. We quantified the effect of soil water content of topsoil/subsoil layers (wet/wet, wet/dry, and dry/dry) on stress transmission. 3D measurements of vertical stresses under a towed wheel (800/50R34) were performed in situ in a Stagnic Luvisol. The tyre was loaded with 60 kN, and we used...... were measured in separate tests. Increase of water content in the topsoil by 114% increased the contact area by 149%, decreased the vertical stresses at the tyre–soil interface by 50%, and decreased the maximum vertical stress at 0.3 and 0.6 m depth by 46 and 63%, respectively. Stress attenuation...

Vertical transmission of group B Streptococcus and associated factors among pregnant women: a cross-sectional study, Eastern Ethiopia

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Yadeta TA

2018-03-01

Full Text Available Tesfaye Assebe Yadeta,1 Alemayehu Worku,2 Gudina Egata,3 Berhanu Seyoum,4 Dadi Marami,4 Yemane Berhane5 1School of Nursing and Midwifery, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia; 2Department of Epidemiology and Biostatistics, School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia; 3School of Public Health, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia; 4Department of Medical Laboratory Science, College of Health and Medical Sciences, Haramaya University, Harar, Ethiopia; 5Department of Epidemiology, Addis Continental Institute of Public Health, Addis Ababa, Ethiopia Background: Vertically transmitted group B Streptococcus (GBS causes fetal and neonatal infections. However, there is limited information on the vertical transmission of GBS in low-income countries. This study, therefore, aimed to determine the rate of vertical transmission of GBS and associated factors among pregnant women in Eastern Ethiopia.Subjects and methods: A cross-sectional, facility-based study was conducted among pregnant women in Harar town, Eastern Ethiopia, from June to October, 2016. GBS positivity of pregnant women was confirmed by culture of rectovaginal swab. Vertical transmission at birth was confirmed by culture on swabs taken from the ear canal, umbilicus, axilla, groin, and nose within 6 hours after birth. Prevalence ratio (PR along with 95% CI was estimated to examine factors associated with vertical transmission using log binomial regression analysis.Results: Out of 231 GBS-colonized pregnant women at delivery, 104 births were identified as GBS colonized with a vertical transmission rate of 45.02% and 95% CI: 38.49, 51.68. Of 104 vertical transmission cases, 65 (62.50% received no intrapartum antibiotic prophylaxis (IAP, 28 (26.92% received it <4 hours before delivery, and 11 (10.58% received it ≥4 hours before delivery. Pre-labor rupture of membranes at term (PR: 1.93; 95

Vertical transmission of macular telangiectasia type 2.

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Delaere, Lien; Spielberg, Leigh; Leys, Anita M

2012-01-01

The purpose of this study was to report vertical transmission of macular telangiectasia type 2 and type 2 diabetes mellitus in 3 families. In this retrospective interventional case series, the charts of patients with inherited macular telangiectasia type 2 were reviewed. A large spectrum of presentations of macular telangiectasia type 2 was observed and has been studied with different techniques including best-corrected visual acuity, microperimetry, confocal blue reflectance fundus autofluorescence, fluorescein angiography, and time domain and spectral domain optical coherence tomography. Vertical transmission of macular telangiectasia type 2 and associated type 2 diabetes mellitus is described in 3 families. Symptomatic as well as asymptomatic eyes with macular telangiectasia type 2 were identified. In 2 families, a mother and son experienced visual loss and were diagnosed with macular telangiectasia type 2. All 4 patients had type 2 diabetes. Diabetic retinopathy was observed in one mother and her son. In the third family, the index patient was diagnosed macular telangiectasia type 2 after complaints of metamorphopsia. She and her family members had type 2 diabetes mellitus, and further screening of her family revealed familial macular telangiectasia type 2. None of the patients were treated for macular telangiectasia type 2. Macular telangiectasia type 2 may be more common than previously assumed, as vision can remain preserved and patients may go undiagnosed. Screening of family members is indicated, and detection of mild anomalies is possible using fundus autofluorescence and spectral domain optical coherence tomography.

Transmission of vertical soil stress under agricultural tyres

DEFF Research Database (Denmark)

Keller, Thomas; Berli, M.; Ruiz, S.

2014-01-01

and simulate soil stress under defined loads. Stress in the soil profile at 0.3, 0.5 and 0.7 m depth was measured during wheeling at a water content close to field capacity on five soils (13–66% clay). Stress transmission was then simulated with a semi-analytical model, using vertical stress at 0.1 m depth......The transmission of stress induced by agricultural machinery within an agricultural soil is typically modelled on the basis of the theory of stress transmission in elastic media, usually in the semi-empirical form that includes the “concentration factor” (v). The aim of this paper was to measure...... estimated from tyre characteristics as the upper boundary condition, and v was obtained at minimum deviation between measurements and simulations. For the five soils, we obtained an average v of 3.5 (for stress transmitting from 0.1 to 0.7 m depth). This was only slightly different from v = 3 for which...

Natural vertical transmission of dengue viruses by Aedes aegypti in Bolivia

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Le Goff, G.; Revollo, J.; Guerra, M.; Cruz, M.; Barja Simon, Z.; Roca, Y.; Vargas Florès, J.; Hervé, J.P.

2011-01-01

The natural transmission of dengue virus from an infected female mosquito to its progeny, namely the vertical transmission, was researched in wild caught Aedes aegypti during an important outbreak in the town of Santa Cruz de la Sierra, Bolivia. Mosquitoes were collected at the preimaginal stages (eggs, larvae and pupae) then reared up to adult stage for viral detection using molecular methods. Dengue virus serotypes 1 and 3 were found to be co-circulating with significant higher prevalence in male than in female mosquitoes. Of the 97 pools of Ae. aegypti (n = 635 male and 748 female specimens) screened, 14 pools, collected in February-May in 2007, were found positive for dengue virus infection: five DEN-1 and nine DEN-3. The average true infection rate (TIR) and minimum infection rate (MIR) were respectively 1.08% and 1.01%. These observations suggest that vertical transmission of dengue virus may be detected in vectors at the peak of an outbreak as well as several months before an epidemic occurs in human population. PMID:21894270

Diverse strategies for vertical symbiont transmission among subsocial stinkbugs.

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Takahiro Hosokawa

Full Text Available Sociality may affect symbiosis and vice versa. Many plant-sucking stinkbugs harbor mutualistic bacterial symbionts in the midgut. In the superfamily Pentatomoidea, adult females excrete symbiont-containing materials from the anus, which their offspring ingest orally and establish vertical symbiont transmission. In many stinkbug families whose members are mostly non-social, females excrete symbiont-containing materials onto/beside eggs upon oviposition. However, exceptional cases have been reported from two subsocial species representing the closely related families Cydnidae and Parastrachiidae, wherein females remain nearby eggs for maternal care after oviposition, and provide their offspring with symbiont-containing secretions at later stages, either just before or after hatching. These observations suggested that sociality of the host stinkbugs may be correlated with their symbiont transmission strategies. However, we found that cydnid stinkbugs of the genus Adomerus, which are associated with gammaproteobacterial gut symbionts and exhibit elaborate maternal care over their offspring, smear symbiont-containing secretions onto eggs upon oviposition as many non-social stinkbugs do. Surface sterilization of the eggs resulted in aposymbiotic insects of slower growth, smaller size and abnormal body coloration, indicating vertical symbiont transmission via egg surface contamination and presumable beneficial nature of the symbiosis. The Adomerus symbionts exhibited AT-biased nucleotide compositions, accelerated molecular evolutionary rates and reduced genome size, while these degenerative genomic traits were less severe than those in the symbiont of a subsocial parastrachiid. These results suggest that not only sociality but also other ecological and evolutionary aspects of the host stinkbugs, including the host-symbiont co-evolutionary history, may have substantially affected their symbiont transmission strategies.

Similar sponge-associated bacteria can be acquired via both vertical and horizontal transmission

DEFF Research Database (Denmark)

Sipkema, Detmer; de Caralt, Sònia; Morillo, Jose A

2015-01-01

Marine sponges host diverse communities of microorganisms that are often vertically transmitted from mother to oocyte or embryo. Horizontal transmission has often been proposed to co-occur in marine sponges, but the mechanism is poorly understood. To assess the impact of the mode of transmission...... on the microbial assemblages of sponges, we analysed the microbiota in sympatric sponges that have previously been reported to acquire bacteria via either vertical (Corticium candelabrum and Crambe crambe) or horizontal transmission (Petrosia ficiformis). The comparative study was performed by PCR......-DGGE and pyrosequencing of barcoded PCR-amplified 16S rRNA gene fragments. We found that P. ficiformis and C. candelabrum each harbor their own species-specific bacteria, but they are similar to other high-microbial-abundance sponges, while the low-microbial-abundance sponge C. crambe hosts microbiota of a very different...

Community voices: barriers and opportunities for programmes to successfully prevent vertical transmission of HIV identified through consultations among people living with HIV.

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Anderson, Ginna; Caswell, Georgina; Edwards, Olive; Hsieh, Amy; Hull, Beri; Mallouris, Christoforos; Mason, Naisiadet; Nöstlinger, Christiana

2012-07-11

In 2010, two global networks of people living with HIV, the International Community of Women Living with HIV (ICW Global) and the Global Network of People living with HIV (GNP+) were invited to review a draft strategic framework for the global scale up of prevention of vertical transmission (PVT) through the primary prevention of HIV and the prevention of unintended pregnancies among women living with HIV. In order to ensure recommendations were based on expressed needs of people living with HIV, GNP+ and ICW Global undertook a consultation amongst people living with HIV which highlighted both facilitators and barriers to prevention services. This commentary summarizes the results of that consultation. The consultation was comprised of an online consultation (moderated chat-forum with 36 participants from 16 countries), an anonymous online e-survey (601 respondents from 58 countries), and focus-group discussions with people living with HIV in Jamaica (27 participants). The consultation highlighted the discrepancies across regions with respect to access to essential packages of PVT services. However, the consultation participants also identified common barriers to access, including a lack of trustworthy sources of information, service providers' attitudes, and gender-based violence. In addition, participant responses revealed common facilitators of access, including quality counselling on reproductive choices, male involvement, and decentralized services. The consultation provided some understanding and insight into the participants' experiences with and recommendations for PVT strategies. Participants agreed that successful, comprehensive PVT programming require greater efforts to both prevent primary HIV infection among young women and girls and, in particular, targeted efforts to ensure that women living with HIV and their partners are supported to avoid unintended pregnancies and to have safe, healthy pregnancies instead. In addition to providing the insights

VERTICAL TRANSMISSION OF DENGUE INFECTION: THE FIRST PUTATIVE CASE REPORTED IN CHINA

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Xueru YIN

Full Text Available SUMMARY Dengue is a systemic viral infection that is commonly transmitted between humans via mosquitoes. Other modes of transmission such as the vertical one are rare and have been infrequently reported in the literature. This report investigates one case of vertical transmission of dengue in Guangzhou, China. A G1P1 lady at 39 weeks of gestation was referred to the Huzhong Hospital presenting a fever for two days. She subsequently developed a skin rash on the back and lower limb and at that time she had already experienced five days of fever. She subsequently went into labor and delivered a female neonate weighting 3,500 g at birth. The neonate developed fever on the third day of life which was associated with a systemic erythematous skin rash. There was no report or evidence of mosquito bites after birth. A complete blood count showed leucopenia, thrombocytopenia and anemia and the liver function test showed elevated AST, GGT and bilirubin. Dengue was diagnosed in the mother and the neonate by the ELISA dengue virus NS1 antigen test (Wantai, Beijing, China and dengue virus fluorogenic quantitative PCR test (Liferiver, Shanghai, China.The case report illustrates the possibility of the vertical transmission of dengue. Clinicians should be alert to this possibility and institute early treatment. Further direct evidence and research are required.

Long-term infection and vertical transmission of a gammaretrovirus in a foreign host species.

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Sakuma, Toshie; Tonne, Jason M; Malcolm, Jessica A; Thatava, Tayaramma; Ohmine, Seiga; Peng, Kah-Whye; Ikeda, Yasuhiro

2012-01-01

Increasing evidence has indicated natural transspecies transmission of gammaretroviruses; however, viral-host interactions after initial xeno-exposure remain poorly understood. Potential association of xenotropic murine leukemia virus-related virus (XMRV) in patients with prostate cancer and chronic fatigue syndrome has attracted broad interests in this topic. Although recent studies have indicated that XMRV is unlikely a human pathogen, further understanding of XMRV xenoinfection would allow in vivo modeling of the initial steps of gammaretroviral interspecies transmission, evolution and dissemination in a new host population. In this study, we monitored the long-term consequences of XMRV infection and its possible vertical transmission in a permissive foreign host, wild-derived Mus pahari mice. One year post-infection, XMRV-infected mice showed no notable pathological changes, while proviral DNA was detected in three out of eight mice. XMRV-infected mice remained seropositive throughout the study although the levels of gp70 Env- and p30 capsid-specific antibodies gradually decreased. When vertical XMRV transmission was assessed, no viremia, humoral immune responses nor endogenization were observed in nine offspring from infected mothers, yet one offspring was found PCR-positive for XMRV-specific sequences. Amplified viral sequences from the offspring showed several mutations, including one amino acid deletion in the receptor binding domain of Env SU. Our results therefore demonstrate long-term asymptomatic infection, low incidence of vertical transmission and limited evolution of XMRV upon transspecies infection of a permissive new host, Mus pahari.

Long-term infection and vertical transmission of a gammaretrovirus in a foreign host species.

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Toshie Sakuma

Full Text Available Increasing evidence has indicated natural transspecies transmission of gammaretroviruses; however, viral-host interactions after initial xeno-exposure remain poorly understood. Potential association of xenotropic murine leukemia virus-related virus (XMRV in patients with prostate cancer and chronic fatigue syndrome has attracted broad interests in this topic. Although recent studies have indicated that XMRV is unlikely a human pathogen, further understanding of XMRV xenoinfection would allow in vivo modeling of the initial steps of gammaretroviral interspecies transmission, evolution and dissemination in a new host population. In this study, we monitored the long-term consequences of XMRV infection and its possible vertical transmission in a permissive foreign host, wild-derived Mus pahari mice. One year post-infection, XMRV-infected mice showed no notable pathological changes, while proviral DNA was detected in three out of eight mice. XMRV-infected mice remained seropositive throughout the study although the levels of gp70 Env- and p30 capsid-specific antibodies gradually decreased. When vertical XMRV transmission was assessed, no viremia, humoral immune responses nor endogenization were observed in nine offspring from infected mothers, yet one offspring was found PCR-positive for XMRV-specific sequences. Amplified viral sequences from the offspring showed several mutations, including one amino acid deletion in the receptor binding domain of Env SU. Our results therefore demonstrate long-term asymptomatic infection, low incidence of vertical transmission and limited evolution of XMRV upon transspecies infection of a permissive new host, Mus pahari.

Two profitless delays for an SEIRS epidemic disease model with vertical transmission and pulse vaccination

International Nuclear Information System (INIS)

Meng Xinzhu; Jiao Jianjun; Chen Lansun

2009-01-01

Since the investigation of impulsive delay differential equations is beginning, the literature on delay epidemic models with pulse vaccination is not extensive. In this paper, we propose a new SEIRS epidemic disease model with two profitless delays and vertical transmission, and analyze the dynamics behaviors of the model under pulse vaccination. Using the discrete dynamical system determined by the stroboscopic map, we obtain a 'infection-free' periodic solution, further, show that the 'infection-free' periodic solution is globally attractive when some parameters of the model are under appropriate conditions. Using a new modeling method, we obtain sufficient condition for the permanence of the epidemic model with pulse vaccination. We show that time delays, pulse vaccination and vertical transmission can bring different effects on the dynamics behaviors of the model by numerical analysis. Our results also show the delays are 'profitless'. In this paper, the main feature is to introduce two discrete time delays, vertical transmission and impulse into SEIRS epidemic model and to give pulse vaccination strategies.

Fatores protetores e de risco envolvidos na transmissão vertical do HIV-1 Protective and risk factors related to vertical transmission of the HIV-1

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Rosângela P. Gianvecchio

2005-04-01

Full Text Available Este estudo avalia os fatores maternos e fetais envolvidos na transmissão vertical do HIV-1 em 47 pares de mãe e filho. As variáveis comportamentais, demográficas e obstétricas foram obtidas mediante entrevista; os dados referentes ao parto e ao recém-nascido, dos prontuários das maternidades. Durante o terceiro trimestre de gestação foi realizada a contagem da carga viral materna e dos linfócitos T CD4+. A média de idade foi de 25 anos e 23,4% das gestantes eram primigestas, e o fator comportamental mais prevalente foi não usar preservativos. Dentre as gestantes, 48,9% tinham células CD4+ superior a 500 células/mm³ e 93,6% se enquadravam na categoria clínica A; 95,7% submeteram-se à profilaxia com zidovudina durante a gestação ou no parto, a qual foi ministrada a todos os recém-nascidos; 50,0% delas foram submetidas à cesárea eletiva. Apesar de expostas a vários fatores de risco e protetores, nenhuma criança tornou-se infectada. A transmissão vertical resulta de um desequilíbrio entre os fatores, com predomínio dos de risco sobre os protetores.This study aimed to evaluate maternal and fetal factors related to vertical transmission of HIV-1. Participants included 47 mother-child pairs. Behavioral, demographic, and obstetric data were obtained through interviews. Data related to delivery and newborns were collected from registries in the maternity hospitals. During the third trimester of pregnancy, CD4+ T lymphocytes and maternal viral load were measured. Mean age of the mothers was 25 years and 23.4% of the pregnant women were primigravidae. The most prevalent behavioral factor was lack of condom use. 48.9% of the women presented a CD4+ count greater than 500 cells/ mm³, and 93.6% belonged to clinical category A. 95.7% of the women received zidovudine prophylaxis during pregnancy or childbirth, and the medication was also administered to all the neonates. 50.0% of patients were submitted to elective cesareans. Despite

Vertical transmission of HIV-1 in the western region of the State of São Paulo

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Vera Lúcia Maria Alves Gonçalves

2011-02-01

Full Text Available INTRODUCTION: This study aimed to determine the prevalence of vertical HIV-1 transmission in the western region of the State of São Paulo, Brazil. METHODS: The study analyzed the medical records of HIV-1-infected mothers and infant pairs living in the municipalities of São Paulo Regional Health Departments DRS II (Araçatuba and DRS XI (Presidente Prudente. From March 2001 to March 2006, blood samples were collected and referred to the Molecular Biology Unit of the Adolfo Lutz Institute (ALI, Presidente Prudente. HIV-1-RNA viral load was determined by bDNA assay. RESULTS: The number of births (109/217, 50.2% and vertical HIV-1 transmissions (6/109, 5.5% that occurred in DRS II was similar to births (108/217, 49.8% and vertical transmissions (7/108, 6.5% in DRS XI (p > 0.05. Although 80% (4/5 of the infected children were male in DRS II, while in DRS XI, 75% (6/8 were female, no differences between sex regarding infected and noninfected children in the regions of Araçatuba and Presidente Prudente were verified. The overall vertical HIV-1 transmission rate was 6%. No consistent reduction in the prevalence of vertical HIV-1 transmission occurred over the years. About 20% of mothers did not know the HIV-1 status of their newborns eight months after delivery. CONCLUSIONS: In the present study, MTCT prevalence rates were about 70% higher than those previously determined in the State of São Paulo, with noreduction throughout the period.Furthermore, a significant number of mothers did not know the HIV-status of their newborns eight months after delivery.

Knowledge of HIV serodiscordance, transmission, and prevention among couples in Durban, South Africa.

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William Kilembe

Full Text Available Couples' voluntary HIV counseling and testing (CVCT significantly decreases HIV transmission within couples, the largest risk group in sub-Saharan Africa, but it is not currently offered in most HIV testing facilities. To roll out such an intervention, understanding locale-specific knowledge barriers is critical. In this study, we measured knowledge of HIV serodiscordance, transmission, and prevention before and after receipt of CVCT services in Durban.Pre- and post-CVCT knowledge surveys were administered to a selection of individuals seeking CVCT services.Changes in knowledge scores were assessed with McNemar Chi-square tests for balanced data and generalized estimating equation methods for unbalanced data.The survey included 317 heterosexual black couples (634 individuals who were primarily Zulu (87%, unemployed (47%, and had at least a secondary level education (78%. 28% of couples proved to be discordant. Only 30% of individuals thought serodiscordance between couples was possible pre-CVCT compared to 95% post-CVCT. One-third thought there was at least one benefit of CVCT pre-CVCT, increasing to 96% post-CVCT. Overall, there were positive changes in knowledge about HIV transmission and prevention. However, many respondents thought all HIV positive mothers give birth to babies with AIDS (64% pre-CVCT, 59% post-CVCT and that male circumcision does not protect negative men against HIV (70% pre-CVCT, 67% post-CVCT.CVCT was well received and was followed by improvements in understanding of discordance, the benefits of joint testing, and HIV transmission. Country-level health messaging would benefit from targeting gaps in knowledge about serodiscordance, vertical transmission, and male circumcision.

First report of venereal and vertical transmission of canine leishmaniosis from naturally infected dogs in Germany

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Naucke Torsten J

2012-04-01

Full Text Available Abstract Background Canine leishmaniosis (CanL is a zoonotic disease caused by Leishmania (L. infantum. It is endemic to several tropical and subtropical countries but also to the Mediterranean region. It is transmitted by phlebotomine sandflies but occasional non-vector transmissions have been reported, including vertical and horizontal transmission. Findings The authors report a case of CanL in a female boxer dog from Dusseldorf, Germany, that had never been in an endemic region. A serum sample from the bitch was tested positive for antibodies against Leishmania (IFAT 1:2,000, ELISA 72. The bitch had whelped three litters, and one puppy from the third litter was also found to be seropositive for Leishmania antibodies (IFAT 1:4,000, ELISA 78. Conclusions Up to now, despite intensive searching, the occurrence of sandflies could not be proved in the bitch's region of origin. Thus, vertical and horizontal transmission are to be discussed as possible ways of infection. This may be the first report of venereal and vertical transmission of L. infantum in naturally infected dogs in Germany.

VERTICAL TRANSMISSION OF HIV: A STUDY PERFORMED AT THE MUNICIPALITY OF SOUTHWEST BAIANO

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Maria Tereza Magalhães Morais

2014-09-01

Full Text Available The Human Immunodeficiency Virus (HIV is a Retrovirus RNA of simple filament, responsible for the Acquired Immune Deficiency Syndrome (AIDS. The virus affects the body's immunologic system destroying the defense cells, particularly the CD4 + T lymphocytes. By the infection of women of reproductive age comes another form of HIV transmission, the vertical transmission, it is a kind of contamination from mother to fetus or to newborn. Such transmission can occur during pregnancy, through birth or through breastfeeding. The research's scope was to evaluate the social and economic profile of HIV positive pregnant women among 2007- 2012, in a city located in southwestern of Bahia (Brazil country. Through data primaries gathered by analyzing records research and notification of HIV positive pregnant women living in Vitória da Conquista, Bahia, Brazil, registered in the Information System for Notifiable Diseases (SINAN could be verified records of 110 cases of pregnant women infected by HIV in the city among the researched period. Through the research, could be verified a high rate of young women with low education level and living in the urban area of city, as well a low rate of vertical transmission.

Neonatal Anaplasma platys infection in puppies: Further evidence for possible vertical transmission

Czech Academy of Sciences Publication Activity Database

Matei, I.A.; Stuen, S.; Modrý, David; Degan, A.; D'Amico, G.; Mihalca, A. D.

2017-01-01

Roč. 219, 1 January (2017), s. 40-41 ISSN 1090-0233 Institutional support: RVO:60077344 Keywords : Anaplasma platys * canine * vertical transmission Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine OBOR OECD: Veterinary science Impact factor: 1.802, year: 2016

Prevenção da transmissão vertical do HIV: atitude dos obstetras em Salvador, Brasil Prevention of HIV vertical transmission: obstetricians'atitude in Salvador, Brasil

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João Paulo Queiroz Farias

2008-03-01

Full Text Available OBJETIVO: avaliar as atitudes e conhecimento dos obstetras das maternidades públicas da cidade de Salvador (MPS sobre as recomendações do Ministério da Saúde para a profilaxia da transmissão vertical do vírus humano da imunodeficiência (HIV e terapia antiretroviral em gestantes. Avaliou-se também a influência das condições de trabalho, disponibilidade da testagem rápida e da terapia antiretroviral em relação à aplicação destas recomendações. MÉTODOS: realizou-se um estudo de corte transversal entre agosto e novembro de 2005, envolvendo 129/152 (85% dos obstetras de todas as MPS. Utilizou-se como instrumento um questionário anônimo, estruturado e auto-explicativo, com questões sobre as características da população, condições de trabalho e disponibilidade de insumos, conhecimento e atitudes relacionadas ao aconselhamento e testagem para o HIV e condutas com as pacientes (uso da zidovudina (AZT, reconhecimento de fatores de risco, escolha e manejo da via de parto e cuidados no puerpério. RESULTADOS: dos obstetras, 69% referiram conhecer integralmente as recomendações do Ministério da Saúde; 90,7% concordaram com a solicitação compulsória da testagem rápida para o HIV; 63,6% escolheram a cesariana para via de parto; 38% contra-indicaram o parto por via vaginal; 37,5% recomendaram isolamento das pacientes soropositivas e 58,1% indicaram laqueadura tubária. A maioria (90% dos sujeitos referiram a existência de fatores prejudiciais à aplicabilidade das recomendações, sendo que os mais apontados foram a realização inadequada e a indisponibilidade das informações do pré-natal na admissão. Embora a testagem rápida estivesse disponível, apenas um terço dos entrevistados afirmou que o resultado estava sempre disponível em tempo hábil. CONCLUSÕES: algumas atitudes relacionadas à assistência à gestante com HIV foram discordantes das recomendações do Ministério da Saúde. Na opinião dos

Health workers' views on quality of prevention of mother-to-child transmission and postnatal care for HIV-infected women and their children

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Hardon Anita

2009-05-01

Full Text Available Abstract Background Prevention of mother-to-child transmission has been considered as not a simple intervention but a comprehensive set of interventions requiring capable health workers. Viet Nam's extensive health care system reaches the village level, but still HIV-infected mothers and children have received inadequate health care services for prevention of mother-to-child transmission. We report here the health workers' perceptions on factors that lead to their failure to give good quality prevention of mother-to-child transmission services. Methods Semistructured interviews with 53 health workers and unstructured observations in nine health facilities in Hanoi were conducted. Selection of respondents was based on their function, position and experience in the development or implementation of prevention of mother-to-child transmission policies/programmes. Results Factors that lead to health workers' failure to give good quality services for prevention of mother-to-child transmission include their own fear of HIV infection; lack of knowledge on HIV and counselling skills; or high workloads and lack of staff; unavailability of HIV testing at commune level; shortage of antiretroviral drugs; and lack of operational guidelines. A negative attitude during counselling and provision of care, treating in a separate area and avoidance of providing service at all were seen by health workers as the result of fear of being infected, as well as distrust towards almost all HIV-infected patients because of the prevailing association with antisocial behaviours. Additionally, the fragmentation of the health care system into specialized vertical pillars, including a vertical programme for HIV/AIDS, is a major obstacle to providing a continuum of care. Conclusion Many hospital staff were not being able to provide good care or were even unwilling to provide appropriate care for HIV-positive pregnant women The study suggests that the quality of prevention of

An investigation on vertical transmission of Leishmania infantum in experimentally infected dogs and assessment of offspring's infectiousness potential by xenodiagnosis.

Science.gov (United States)

Ben Slimane, T; Chouihi, E; Ben Hadj Ahmed, S; Chelbi, I; Barhoumi, W; Cherni, S; Zoghlami, Z; Gharbi, M; Zhioua, E

2014-12-15

Dogs are the main reservoir host of Leishmania infantum, etiologic agent of human visceral leishmaniasis (HVL) and canine visceral leishmaniasis (CVL). Transmission of L. infantum to humans and dogs is mainly through the bite of infected sand flies. In the Western Mediterranean basin, Phlebotomus perniciosus is the main vector of L. infantum. However, occasional vertical transmission of L. infantum has been reported. This study investigated L. infantum vertical transmission in offspring of experimentally infected dogs. Among 14 surviving puppies from three female beagle dogs that developed CVL following an experimental infection with L. infantum, one was tested positive by indirect immunofluorescence antibody test, by PCR and by xenodiagnosis with a high parasite burden in the spleen at 14 months old. None of the remaining puppies were tested positive for L. infantum. These findings strongly suggest that infected puppies following vertical transmission can sustain infection and contribute in infecting sand flies with L. infantum. Any strategy for controlling CVL should take into consideration the vertical transmission of L. infantum. Copyright © 2014 Elsevier B.V. All rights reserved.

Maternal Proviral Load and Vertical Transmission of Human T Cell Lymphotropic Virus Type 1 in Guinea-Bissau

NARCIS (Netherlands)

van Tienen, Carla; McConkey, Samuel J.; de Silva, Thushan I.; Cotten, Matthew; Kaye, Steve; Sarge-Njie, Ramu; da Costa, Carlos; Gonçalves, Nato; Parker, Julia; Vincent, Tim; Jaye, Assan; Aaby, Peter; Whittle, Hilton; Schim van der Loeff, Maarten

2012-01-01

The relative importance of routes of transmission of human T cell lymphotropic virus type 1 (HTLV-1) in Guinea-Bissau is largely unknown; vertical transmission is thought to be important, but there are very few existing data. We aimed to examine factors associated with transmission in mothers and

Rhabdoviruses in two species of Drosophila: vertical transmission and a recent sweep.

Science.gov (United States)

Longdon, Ben; Wilfert, Lena; Obbard, Darren J; Jiggins, Francis M

2011-05-01

Insects are host to a diverse range of vertically transmitted micro-organisms, but while their bacterial symbionts are well-studied, little is known about their vertically transmitted viruses. We have found that two sigma viruses (Rhabdoviridae) recently discovered in Drosophila affinis and Drosophila obscura are both vertically transmitted. As is the case for the sigma virus of Drosophila melanogaster, we find that both males and females can transmit these viruses to their offspring. Males transmit lower viral titers through sperm than females transmit through eggs, and a lower proportion of their offspring become infected. In natural populations of D. obscura in the United Kingdom, we found that 39% of flies were infected and that the viral population shows clear evidence of a recent expansion, with extremely low genetic diversity and a large excess of rare polymorphisms. Using sequence data we estimate that the virus has swept across the United Kingdom within the past ∼11 years, during which time the viral population size doubled approximately every 9 months. Using simulations based on our lab estimates of transmission rates, we show that the biparental mode of transmission allows the virus to invade and rapidly spread through populations at rates consistent with those measured in the field. Therefore, as predicted by our simulations, the virus has undergone an extremely rapid and recent increase in population size. In light of this and earlier studies of a related virus in D. melanogaster, we conclude that vertically transmitted rhabdoviruses may be common in insects and that these host-parasite interactions can be highly dynamic.

Rhabdoviruses in Two Species of Drosophila: Vertical Transmission and a Recent Sweep

Science.gov (United States)

Longdon, Ben; Wilfert, Lena; Obbard, Darren J.; Jiggins, Francis M.

2011-01-01

Insects are host to a diverse range of vertically transmitted micro-organisms, but while their bacterial symbionts are well-studied, little is known about their vertically transmitted viruses. We have found that two sigma viruses (Rhabdoviridae) recently discovered in Drosophila affinis and Drosophila obscura are both vertically transmitted. As is the case for the sigma virus of Drosophila melanogaster, we find that both males and females can transmit these viruses to their offspring. Males transmit lower viral titers through sperm than females transmit through eggs, and a lower proportion of their offspring become infected. In natural populations of D. obscura in the United Kingdom, we found that 39% of flies were infected and that the viral population shows clear evidence of a recent expansion, with extremely low genetic diversity and a large excess of rare polymorphisms. Using sequence data we estimate that the virus has swept across the United Kingdom within the past ∼11 years, during which time the viral population size doubled approximately every 9 months. Using simulations based on our lab estimates of transmission rates, we show that the biparental mode of transmission allows the virus to invade and rapidly spread through populations at rates consistent with those measured in the field. Therefore, as predicted by our simulations, the virus has undergone an extremely rapid and recent increase in population size. In light of this and earlier studies of a related virus in D. melanogaster, we conclude that vertically transmitted rhabdoviruses may be common in insects and that these host–parasite interactions can be highly dynamic. PMID:21339477

Vertical transmission of infectious hematopoietic necrosis virus in sockeye salmon (Oncorhynchus nerka): Isolation of virus from dead eggs and fry

Science.gov (United States)

Mulcahy, D.; Pascho, R.J.

1985-01-01

The control of epizootics of infectious haematopoietic necrosis (IHN) virus in salmonid fishes is presently based on examination and certification of adult brood fish to prevent the introduction of virus-infected eggs into hatcheries (Canadian Fisheries and Marine Service 1976; McDaniel 1979). This strategy is based on the assumption that the virus is vertically transmitted in association with the gametes. However, evidence for vertical transmission of IHN virus is circumstantial, based mostly on the appearance of the disease outside the enzootic area (the west coast of North America) in fish hatched from eggs obtained from within that area (Plumb 1972; Holway & Smith 1973; Wolf, Quimby, Pettijohn & Landolt 1973; Sano, Nishimura, Okamoto, Yamazaki, Hanada & Watanabe1977; Carlisle, Schat & Elston 1979). An indirect demonstration of vertical transmission was made by placing known virus-free fish in the water above and below raceways containing fish that suffered an IHN epizootic in an effort to eliminate waterborne virus as a source of infection (Wingfield & Chan 1970). The fish placed below the raceway developed IHN, due to waterborne virus released from the affected fish in the raceway, but the fish placed above the raceway failed to develop IHN. These results suggested that the source of infection of the fish in the raceway was not the water supply, although it is possible that the virus was no longer present in the water supply at the time the sentinel fish were exposed to the water.

Prevalência de HIV em gestantes e transmissão vertical segundo perfil socioeconômico, Vitória, ES

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Anne Caroline Barbosa Cerqueira Vieira

2011-08-01

Full Text Available OBJETIVO: Descrever a prevalência de infecção por HIV em gestantes e a taxa de transmissão vertical, segundo o perfil socioeconômico dos bairros de residência das mães. MÉTODOS: Estudo ecológico exploratório utilizando a base de dados do Sistema de Informação de Agravos de Notificação de gestantes HIV-positivas e aids em crianças notificadas entre 2000 e 2006 em Vitória, ES. Para análise das informações socioeconômicas foi utilizado o Índice de Qualidade Urbana. A prevalência de HIV em gestantes e a taxa de transmissão vertical foram calculadas. A distribuição espacial dos casos foi realizada no programa Terraview 3.2.0. Para verificar a associação entre a qualidade urbana e a prevalência de HIV em gestantes utilizou-se o modelo de regressão de Poisson. RESULTADOS: Um total de 137 gestantes e 14 crianças infectadas por transmissão vertical foi notificado no período. Sete crianças correspondiam a mães HIV-positivas sem notificação de caso no período analisado. A prevalência de infecção em gestantes no período foi de 0,44% e a taxa de transmissão vertical foi de 9,7%. CONCLUSÕES: A prevalência de infecção por HIV em gestantes e a transmissão vertical associam-se à qualidade urbana do bairro de residência, indicando que os bairros com menor qualidade urbana devem ser priorizados quanto às ações para redução da transmissão vertical.

The magnitude of syphilis: from prevalence to vertical transmission.

Science.gov (United States)

Cerqueira, Luciane Rodrigues Pedreira de; Monteiro, Denise L M; Taquette, Stella R; Rodrigues, Nádia C P; Trajano, Alexandre J B; Souza, Flavio Monteiro de; Araújo, Bianca De Melo

2017-12-21

In 2013, the World Health Organization (WHO) reported that 1.9 million pregnant women were infected with syphilis worldwide, of which 66.5% had adverse fetal effects in cases of untreated syphilis. Congenital syphilis contributes significantly to infant mortality, accounting for 305,000 perinatal deaths worldwide annually. To estimate the prevalence of syphilis in parturients, the incidence of congenital syphilis and the vertical transmission rate. a cross-sectional study with data collected from 2041 parturients who had undergone treatment between 2012 and 2014 in the maternity section of the Pedro Ernesto Hospital of the State University of Rio de Janeiro, in the metropolitan area of Rio de Janeiro. The inclusion criterion was positive VDRL and treponemal test in a hospital environment. the prevalence of syphilis in pregnant women was 4.1% in 2012, 3.1% in 2013 and 5% in 2014, with official reporting of 15.6%, 25.0% and 48.1%, respectively. The incidence of congenital syphilis (CS) was 22/1,000 in live births (LB) in 2012; 17/1,000 LB in 2013 and 44.8/1,000 LB in 2014. CS underreporting during the period was 6.7%. Vertical transmission occurred in 65.8% of infants from infected mothers. It was concluded that, in 34.6% of the CS cases, maternal VDRL titers were = 1/4. Results demonstrate the magnitude of the disease, fragility of the reporting system in the assessment of the actual prevalence, impact on perinatal outcomes, and they are a warning about the real situation of syphilis, which is still underestimated in the State.

An Audit of Perineal Trauma and Vertical Transmisson Of HIV ...

African Journals Online (AJOL)

Restrictive episiotomy is recommended for the prevention of vertical transmission of HIV. The study compared the frequency of episiotomy use and the occurrence of perineal tears; and related factors in HIV positive and HIV negative women and to assess their effect on Mother-to-child transmission (MTCT) of HIV. A total of ...

Threshold Dynamics of a Stochastic SIR Model with Vertical Transmission and Vaccination

OpenAIRE

Miao, Anqi; Zhang, Jian; Zhang, Tongqian; Pradeep, B. G. Sampath Aruna

2017-01-01

A stochastic SIR model with vertical transmission and vaccination is proposed and investigated in this paper. The threshold dynamics are explored when the noise is small. The conditions for the extinction or persistence of infectious diseases are deduced. Our results show that large noise can lead to the extinction of infectious diseases which is conducive to epidemic diseases control.

Strategies to prevent HIV transmission to serodiscordant couples.

Science.gov (United States)

Hallal, Ronaldo Campos; Raxach, Juan Carlos; Barcellos, Nêmora Tregnago; Maksud, Ivia

2015-09-01

The use antiretroviral reduces the sexual transmission of HIV, expanding interventions for serodiscordant couples. This article aims to review the use of antiretroviral and other prevention interventions among serodiscordant couples and to analyze its use in Brazil. A retrospective review was performed through the MEDLINE database and bases included in the Biblioteca Virtual em Saúde. The articles recovered exhibit four main strategies: (1) condom; (2) reduction of risks in sexual practices; (3) use of antiretrovirals, particularly early initiation of antiretroviral therapy (TASP) and pre-exposure prophylaxis (PrEP); (4) risk reduction in reproduction. TASP is highly effective in reducing sexual transmission, PrEP was tested in serodiscordant couples and both reduce the sexual transmission risk in different sexual practices, enabling individualized prevention strategies. When used in combination, antiretrovirals and sexual practices with condoms offer greater efficacy than any single strategy. The combined use of new and old strategies allows us to build a prevention policy for all.

Strategies to prevent HIV transmission to serodiscordant couples

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Ronaldo Campos Hallal

2015-09-01

Full Text Available ABSTRACTIntroduction:The use antiretroviral reduces the sexual transmission of HIV, expanding interventions for serodiscordant couples.Objective:This article aims to review the use of antiretroviral and other prevention interventions among serodiscordant couples and to analyze its use in Brazil.Methods:A retrospective review was performed through the MEDLINE database and bases included in the Biblioteca Virtual em Saúde.Results:The articles recovered exhibit four main strategies: (1 condom; (2 reduction of risks in sexual practices; (3 use of antiretrovirals, particularly early initiation of antiretroviral therapy (TASP and pre-exposure prophylaxis (PrEP; (4 risk reduction in reproduction.Discussion:TASP is highly effective in reducing sexual transmission, PrEP was tested in serodiscordant couples and both reduce the sexual transmission risk in different sexual practices, enabling individualized prevention strategies.Conclusions:When used in combination, antiretrovirals and sexual practices with condoms offer greater efficacy than any single strategy. The combined use of new and old strategies allows us to build a prevention policy for all.

Risk factors of HIV-1 vertical transmission (VT) and the influence of antiretroviral therapy (ART) in pregnancy outcome.

Science.gov (United States)

Barral, Maria F M; de Oliveira, Gisele R; Lobato, Rubens C; Mendoza-Sassi, Raul A; Martínez, Ana M B; Gonçalves, Carla V

2014-01-01

In the absence of intervention, the rate of vertical transmission of HIV can range from 15-45%. With the inclusion of antiretroviral drugs during pregnancy and the choice of delivery route this amounts to less than 2%. However ARV use during pregnancy has generated several questions regarding the adverse effects of the gestational and neonatal outcome. This study aims to analyze the risk factors for vertical transmission of HIV-1 seropositive pregnant women living in Rio Grande and the influence of the use of ARVs in pregnancy outcome. Among the 262 pregnant women studied the rate of vertical transmission of HIV was found to be 3.8%. Regarding the VT, there was a lower risk of transmission when antiretroviral drugs were used and prenatal care was conducted at the referral service. However, the use of ART did not influence the outcome of pregnancy. However, initiation of prenatal care after the first trimester had an influence on low birth weight, as well as performance of less than six visits increased the risk of prematurity. Therefore, the risk factors analyzed in this study appear to be related to the realization of inadequate pre-natal and maternal behavior.

RISK FACTORS OF HIV-1 VERTICAL TRANSMISSION (VT AND THE INFLUENCE OF ANTIRETROVIRAL THERAPY (ART IN PREGNANCY OUTCOME

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Maria F.M. Barral

2014-04-01

Full Text Available In the absence of intervention, the rate of vertical transmission of HIV can range from 15-45%. With the inclusion of antiretroviral drugs during pregnancy and the choice of delivery route this amounts to less than 2%. However ARV use during pregnancy has generated several questions regarding the adverse effects of the gestational and neonatal outcome. This study aims to analyze the risk factors for vertical transmission of HIV-1 seropositive pregnant women living in Rio Grande and the influence of the use of ARVs in pregnancy outcome. Among the 262 pregnant women studied the rate of vertical transmission of HIV was found to be 3.8%. Regarding the VT, there was a lower risk of transmission when antiretroviral drugs were used and prenatal care was conducted at the referral service. However, the use of ART did not influence the outcome of pregnancy. However, initiation of prenatal care after the first trimester had an influence on low birth weight, as well as performance of less than six visits increased the risk of prematurity. Therefore, the risk factors analyzed in this study appear to be related to the realization of inadequate pre-natal and maternal behavior.

Possible vertical transmission of Bartonella bacilliformis in Peru.

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Tuya, Ximena L; Escalante-Kanashiro, Raffo; Tinco, Carmen; Pons, Maria J; Petrozzi, Verónica; Ruiz, Joaquim; del Valle, Juana

2015-01-01

A 22-day-old male was admitted with a 2-day history of irritability, dyspnea, jaundice, fever, and gastrointestinal bleeding. A thin blood smear was performed, which showed the presence of intraerythrocyte bacteria identified as Bartonella bacilliformis, and subsequently, the child was diagnosed with Carrion's disease. The diagnosis was confirmed by specific polymerase chain reaction. The child was born in a non-endemic B. bacilliformis area and had not traveled to such an area before hospitalization. However, the mother was from an endemic B. bacilliformis area, and posterior physical examination showed the presence of a wart compatible with B. bacilliformis in semi-immune subjects. These data support vertical transmission of B. bacilliformis. © The American Society of Tropical Medicine and Hygiene.

Vertical transmission of infectious haematopoietic necrosis virus in sockeye salmon, Oncorhynchus nerka (Walbaum): isolation of virus from dead eggs and fry

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Mulcahy, D.; Pascho, R.J.

1985-01-01

The control of epizootics of infectious haematopoietic necrosis (IIHN) virus in salmonid fishes is presently based on examination and certification of adult brood fish to prevent the introduction of virus-infected eggs into hatcheries (Canadian Fisherics and Marine Service 1976; McDaniel 1979). This strategy is based on the assumption that the virus is vertically transmitted in association with the gametes. However, evidence for vertical transmission of lHN virus is circumstantial, based mostly on the appearance of the disease outside the enzootic area (the west coast of North America) in fish hatched from eggs obtained from within that area (Plumb 1972; Holway & Smith 1973; Wolf, Quimby, Pettijohn & Landolt 1973, Sano, Nishimura, Okamoto, Yamazaki, Hanada & Watanabe 1977. Carlisle, Schat & Elston 1979). An indirect demonstration of vertical transmission was made by placing known virus-free fish in the water above and below raceways containing fish that suffered an IEEN epizootic in an cffort to climinate waterborne virus as a source of infection (Wingficid & Chan 1970). The fish placed below the raceway developed IHN, due to waterborne virus released from the affected fish in the raceway, but the fish placed above the raceway failed to develop IHN. These results suggested that the source of infection of the fish in the raceway was not the water supply, although it is possible that the virus was no longer present in the water supply at the time the sentinel fish were exposed to the water.

Threshold Dynamics of a Stochastic SIR Model with Vertical Transmission and Vaccination

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Anqi Miao

2017-01-01

Full Text Available A stochastic SIR model with vertical transmission and vaccination is proposed and investigated in this paper. The threshold dynamics are explored when the noise is small. The conditions for the extinction or persistence of infectious diseases are deduced. Our results show that large noise can lead to the extinction of infectious diseases which is conducive to epidemic diseases control.

The magnitude of syphilis: from prevalence to vertical transmission

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Luciane Rodrigues Pedreira de Cerqueira

2017-12-01

Full Text Available ABSTRACT Introduction: In 2013, the World Health Organization (WHO reported that 1.9 million pregnant women were infected with syphilis worldwide, of which 66.5% had adverse fetal effects in cases of untreated syphilis. Congenital syphilis contributes significantly to infant mortality, accounting for 305,000 perinatal deaths worldwide annually. Aim: To estimate the prevalence of syphilis in parturients, the incidence of congenital syphilis and the vertical transmission rate. Material and methods: a cross-sectional study with data collected from 2041 parturients who had undergone treatment between 2012 and 2014 in the maternity section of the Pedro Ernesto Hospital of the State University of Rio de Janeiro, in the metropolitan area of Rio de Janeiro. The inclusion criterion was positive VDRL and treponemal test in a hospital environment. Results: the prevalence of syphilis in pregnant women was 4.1% in 2012, 3.1% in 2013 and 5% in 2014, with official reporting of 15.6%, 25.0% and 48.1%, respectively. The incidence of congenital syphilis (CS was 22/1,000 in live births (LB in 2012; 17/1,000 LB in 2013 and 44.8/1,000 LB in 2014. CS underreporting during the period was 6.7%. Vertical transmission occurred in 65.8% of infants from infected mothers. It was concluded that, in 34.6% of the CS cases, maternal VDRL titers were = 1/4. Conclusion: Results demonstrate the magnitude of the disease, fragility of the reporting system in the assessment of the actual prevalence, impact on perinatal outcomes, and they are a warning about the real situation of syphilis, which is still underestimated in the State.

When prevention of mother-to-child HIV transmission fails: preventing pretreatment drug resistance in African children

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Inzaule, Seth C.; Hamers, Raph L.; Calis, Job; Boerma, Ragna; Sigaloff, Kim; Zeh, Clement; Mugyenyi, Peter; Akanmu, Sulaimon; Rinke de Wit, Tobias F.

2018-01-01

: The scale-up of antiretroviral prophylaxis to prevent mother-to-child transmission of HIV has significantly reduced new pediatric infections in sub-Saharan Africa. However, among infants who become HIV-infected despite prevent mother-to-child transmission, more than 50% have drug-resistant HIV.

Hepatitis C Virus Sensing by Human Trophoblasts Induces Innate Immune Responses and Recruitment of Maternal NK Cells: Potential Implications for Limiting Vertical Transmission.

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Giugliano, Silvia; Petroff, Margaret G; Warren, Bryce D; Jasti, Susmita; Linscheid, Caitlin; Ward, Ashley; Kramer, Anita; Dobrinskikh, Evgenia; Sheiko, Melissa A; Gale, Michael; Golden-Mason, Lucy; Winn, Virginia D; Rosen, Hugo R

2015-10-15

Hepatitis C virus (HCV) is the world's most common blood-borne viral infection for which there is no vaccine. The rates of vertical transmission range between 3 and 6% with odds 90% higher in the presence of HIV coinfection. Prevention of vertical transmission is not possible because of lack of an approved therapy for use in pregnancy or an effective vaccine. Recently, HCV has been identified as an independent risk factor for preterm delivery, perinatal mortality, and other complications. In this study, we characterized the immune responses that contribute to the control of viral infection at the maternal-fetal interface (MFI) in the early gestational stages. In this study, we show that primary human trophoblast cells and an extravillous trophoblast cell line (HTR8), from first and second trimester of pregnancy, express receptors relevant for HCV binding/entry and are permissive for HCV uptake. We found that HCV-RNA sensing by human trophoblast cells induces robust upregulation of type I/III IFNs and secretion of multiple chemokines that elicit recruitment and activation of decidual NK cells. Furthermore, we observed that HCV-RNA transfection induces a proapoptotic response within HTR8 that could affect the morphology of the placenta. To our knowledge, for the first time, we demonstrate that HCV-RNA sensing by human trophoblast cells elicits a strong antiviral response that alters the recruitment and activation of innate immune cells at the MFI. This work provides a paradigm shift in our understanding of HCV-specific immunity at the MFI as well as novel insights into mechanisms that limit vertical transmission but may paradoxically lead to virus-related pregnancy complications. Copyright © 2015 by The American Association of Immunologists, Inc.

High-pass filtering and dynamic gain regulation enhance vertical bursts transmission along the mossy fiber pathway of cerebellum

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Jonathan Mapelli

2010-05-01

Full Text Available Signal elaboration in the cerebellum mossy fiber input pathway presents controversial aspects, especially concerning gain regulation and the spot-like (rather than beam-like appearance of granular-to-molecular layer transmission. By using voltage-sensitive dye (VSD imaging in rat cerebellar slices (Mapelli et al., 2010, we found that mossy fiber bursts optimally excited the granular layer above ~50 Hz and the overlaying molecular layer above ~100 Hz, thus generating a cascade of high-pass filters. NMDA receptors enhanced transmission in the granular, while GABA-A receptors depressed transmission in both the granular and molecular layer. Burst transmission gain was controlled through a dynamic frequency-dependent involvement of these receptors. Moreover, while high-frequency transmission was enhanced along vertical lines connecting the granular to molecular layer, no high-frequency enhancement was observed along the parallel fiber axis in the molecular layer. This was probably due to the stronger effect of Purkinje cell GABA-A receptor-mediated inhibition occurring along the parallel fibers than along the granule cell axon ascending branch. The consequent amplification of burst responses along vertical transmission lines could explain the spot-like activation of Purkinje cells observed following punctuate stimulation in vivo .

The use of social network analysis to examine the transmission of Salmonella spp. within a vertically integrated broiler enterprise.

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Crabb, Helen Kathleen; Allen, Joanne Lee; Devlin, Joanne Maree; Firestone, Simon Matthew; Stevenson, Mark Anthony; Gilkerson, James Rudkin

2018-05-01

To better understand factors influencing infectious agent dispersal within a livestock population information is needed on the nature and frequency of contacts between farm enterprises. This study uses social network analysis to describe the contact network within a vertically integrated broiler poultry enterprise to identify the potential horizontal and vertical transmission pathways for Salmonella spp. Nodes (farms, sheds, production facilities) were identified and the daily movement of commodities (eggs, birds, feed, litter) and people between nodes were extracted from routinely kept farm records. Three time periods were examined in detail, 1- and 8- and 17-weeks of the production cycle and contact networks were described for all movements, and by commodity and production type. All nodes were linked by at least one movement during the study period but network density was low indicating that all potential pathways between nodes did not exist. Salmonella spp. transmission via vertical or horizontal pathways can only occur along directed pathways when those pathways are present. Only two locations (breeder or feed nodes) were identified where the transmission of a single Salmonella spp. clone could theoretically percolate through the network to the broiler or processing nodes. Only the feed transmission pathway directly connected all parts of the network. Copyright © 2017 Elsevier Ltd. All rights reserved.

Performance-based incentives may be appropriate to address challenges to delivery of prevention of vertical transmission of HIV services in rural Mozambique: a qualitative investigation.

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Schuster, Roseanne C; de Sousa, Octávio; Rivera, Jacqueline; Olson, Rebecca; Pinault, Delphine; Young, Sera L

2016-10-07

Performance-based incentives (PBIs) have garnered global attention as a promising strategy to improve healthcare delivery to vulnerable populations. However, literature gaps in the context in which an intervention is implemented and how the PBIs were developed exist. Therefore, we (1) characterized the barriers and promoters to prevention of vertical transmission of HIV (PVT) service delivery in rural Mozambique, where the vertical transmission rate is 12 %, and (2) assessed the appropriateness for a PBI's intervention and application to PVT. We conducted 24 semi-structured interviews with nurses, volunteers, community health workers, and traditional birth attendants about the barriers and promoters they experienced delivering PVT services. We then explored emergent themes in subsequent focus group discussions (n = 7, total participants N = 92) and elicited participant perspectives on PBIs. The ecological motivation-opportunity-ability framework guided our iterative data collection and thematic analysis processes. The interviews revealed that while all health worker cadres were motivated intrinsically and by social recognition, they were dissatisfied with low and late remuneration. Facility-based staff were challenged by factors across the rest of the ecological levels, primarily in the opportunity domain, including the following: poor referral and record systems (work mandate), high workload, stock-outs, poor infrastructure (facility environment), and delays in obtaining patient results and donor payment discrepancies (administrative). Community-based cadres' opportunity challenges included lack of supplies, distance (work environment), lack of incorporation into the health system (administration), and ability challenges of incorrect knowledge (health worker). PBIs based on social recognition and that enable action on intrinsic motivation through training, supervision, and collaboration were thought to have the most potential for targeting improvements

The Threshold of a Stochastic SIRS Model with Vertical Transmission and Saturated Incidence

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Chunjuan Zhu

2017-01-01

Full Text Available The threshold of a stochastic SIRS model with vertical transmission and saturated incidence is investigated. If the noise is small, it is shown that the threshold of the stochastic system determines the extinction and persistence of the epidemic. In addition, we find that if the noise is large, the epidemic still prevails. Finally, numerical simulations are given to illustrate the results.

Micro-size antenna structure with vertical nanowires for wireless power transmission and communication.

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Kang, Jong-Gu; Jeong, Yeri; Shin, Jeong Hee; Choi, Ji-Woong; Sohn, Jung Inn; Cha, Seung Nam; Jang, Jae Eun

2014-11-01

For biomedical implanted devices, a wireless power or a signal transmission is essential to protect an infection and to enhance durability. In this study, we present a magnetic induction technique for a power transmission without any wire connection between transmitter (Tx) and receiver (Rx) in a micro scale. Due to a micro size effect of a flat spiral coil, a magnetic inductance is not high. To enhance the magnetic inductance, a three dimensional magnetic core is added to an antenna structure, which is consisted of ZnO nano wires coated by a nickel (Ni) layer. ZnO nano wires easily supply a large effective surface area with a vertical structural effect to the magnetic core structure, which induces a higher magnetic inductance with a ferro-magnetic material Ni. The magnetic induction antenna with the magnetic core shows a high inductance value, a low reflection power and a strong power transmission. The power transmission efficiencies are tested under the air and the water medium are almost the same values, so that the magnetic induction technique is quite proper to body implanted systems.

[HIV and syphilis coinfection in pregnancy and vertical HIV transmission: a study based on epidemiological surveillance data].

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Acosta, Lisiane M W; Gonçalves, Tonantzin Ribeiro; Barcellos, Nêmora Tregnago

2016-12-01

To estimate the rate of HIV and syphilis coinfection among pregnant women living in Porto Alegre, Brazil, as well as the association of coinfection with vertical HIV transmission and socioeconomic variables. This analytical retrospective cross-sectional study employed data from the regular epidemiological surveillance system for the period from 2010 to 2013. Data were obtained regarding pregnant women with HIV and exposed children, syphilis in pregnancy, and congenital syphilis. The study population included 1 500 HIV-positive women with deliveries from 2010 to 2013. Of these, 155 (10.3%) were also infected with syphilis, corresponding to an HIV and syphilis coinfection rate of 10.2% (± 1.5%). The coinfected group had lower education levels, higher prevalence of black women, and greater HIV exposure related to drug use by the woman or a partner. Coinfected women had more delayed HIV diagnosis (for example, during childbirth) and greater prevalence of lacking prenatal care (44%). Crude analysis showed an association between vertical HIV transmission and HIV and syphilis co-infection (PR = 2.1; 95%CI: 1.21-3.74; P = 0.01) that persisted in the adjusted analysis. A profile of increased vulnerability was identified among pregnant women with HIV and syphilis coinfection. A positive impact of the treatment to reduce congenital syphilis and eliminate vertical transmission of HIV depends on enhanced access to qualified health care.

Vertically acquired hepatitis C virus infection: Correlates of transmission and disease progression.

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Tovo, Pier-Angelo; Calitri, Carmelina; Scolfaro, Carlo; Gabiano, Clara; Garazzino, Silvia

2016-01-28

The worldwide prevalence of hepatitis C virus (HCV) infection in children is 0.05%-0.4% in developed countries and 2%-5% in resource-limited settings, where inadequately tested blood products or un-sterile medical injections still remain important routes of infection. After the screening of blood donors, mother-to-child transmission (MTCT) of HCV has become the leading cause of pediatric infection, at a rate of 5%. Maternal HIV co-infection is a significant risk factor for MTCT and anti-HIV therapy during pregnancy seemingly can reduce the transmission rate of both viruses. Conversely, a high maternal viral load is an important, but not preventable risk factor, because at present no anti-HCV treatment can be administered to pregnant women to block viral replication. Caution is needed in adopting obstetric procedures, such as amniocentesis or internal fetal monitoring, that can favor fetal exposure to HCV contaminated maternal blood, though evidence is lacking on the real risk of single obstetric practices. Mode of delivery and type of feeding do not represent significant risk factors for MTCT. Therefore, there is no reason to offer elective caesarean section or discourage breast-feeding to HCV infected parturients. Information on the natural history of vertical HCV infection is limited. The primary infection is asymptomatic in infants. At least one quarter of infected children shows a spontaneous viral clearance (SVC) that usually occurs within 6 years of life. IL-28B polymorphims and genotype 3 infection have been associated with greater chances of SVC. In general, HCV progression is mild or moderate in children with chronic infection who grow regularly, though cases with marked liver fibrosis or hepatic failure have been described. Non-organ specific autoantibodies and cryoglobulins are frequently found in children with chronic infection, but autoimmune diseases or HCV associated extrahepatic manifestations are rare.

Dual and triple therapy to prevent mother-to-child transmission of ...

African Journals Online (AJOL)

Objective. To determine outcomes of pregnant women and their infants at McCord Hospital in Durban, South Africa, where dual and triple therapy to reduce HIV vertical transmission have been used since 2004 despite national guidelines recommending simpler regimens. Method. We retrospectively examined records of all ...

The unknown risk of vertical transmission in sleeping sickness--a literature review.

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Andreas K Lindner

Full Text Available BACKGROUND: Children with human African trypanosomiasis (HAT present with a range of generally non-specific symptoms. Late diagnosis is frequent with often tragic outcomes. Trypanosomes can infect the foetus by crossing the placenta. Unequivocal cases of congenital infection that have been reported include newborn babies of infected mothers who were diagnosed with HAT in the first 5 days of life and children of infected mothers who had never entered an endemic country themselves. METHODS: This review systematically summarizes the literature on the vertical transmission of HAT, to our knowledge for the first time. To approach the broader aspects of the subject, articles considering the epidemiology of childhood HAT and HAT in pregnancy were also included. The HAT guidelines and technical reports of the World Health Organisation, Médecins Sans Frontières, Institut de Recherche pour le Développement, and of one endemic country were reviewed. RESULTS: Publications describing congenital HAT are very limited and consist only of single case reports and small case series. Generally it is assumed to be a rare event, but it has never been systematically investigated. In two publications, it is hypothesized that congenital HAT occurs more often than suspected. Not all guidelines and not all HAT literature mention this transmission route. CONCLUSIONS: The risk of vertical transmission is unknown. Awareness of congenital HAT is insufficient, and as a result opportunities for an early diagnosis in newborns may be missed. All HAT guidelines and local HAT protocols should stress that in endemic areas pregnant women should be systematically checked for HAT and that newborns of HAT infected mothers should be assessed for the disease as soon as possible. Studies on the impact of HAT on fertility and pregnancy and studies on congenital HAT are long overdue.

Recombinant IgA Is Sufficient To Prevent Influenza Virus Transmission in Guinea Pigs

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Seibert, Christopher W.; Rahmat, Saad; Krause, Jens C.; Eggink, Dirk; Albrecht, Randy A.; Goff, Peter H.; Krammer, Florian; Duty, J. Andrew; Bouvier, Nicole M.; García-Sastre, Adolfo

2013-01-01

A serum hemagglutination inhibition (HAI) titer of 40 or greater is thought to be associated with reduced influenza virus pathogenesis in humans and is often used as a correlate of protection in influenza vaccine studies. We have previously demonstrated that intramuscular vaccination of guinea pigs with inactivated influenza virus generates HAI titers greater than 300 but does not protect vaccinated animals from becoming infected with influenza virus by transmission from an infected cage mate. Only guinea pigs intranasally inoculated with a live influenza virus or a live attenuated virus vaccine, prior to challenge, were protected from transmission (A. C. Lowen et al., J. Virol. 83:2803–2818, 2009.). Because the serum HAI titer is mostly determined by IgG content, these results led us to speculate that prevention of viral transmission may require IgA antibodies or cellular immune responses. To evaluate this hypothesis, guinea pigs and ferrets were administered a potent, neutralizing mouse IgG monoclonal antibody, 30D1 (Ms 30D1 IgG), against the A/California/04/2009 (H1N1) virus hemagglutinin and exposed to respiratory droplets from animals infected with this virus. Even though HAI titers were greater than 160 1 day postadministration, Ms 30D1 IgG did not prevent airborne transmission to passively immunized recipient animals. In contrast, intramuscular administration of recombinant 30D1 IgA (Ms 30D1 IgA) prevented transmission to 88% of recipient guinea pigs, and Ms 30D1 IgA was detected in animal nasal washes. Ms 30D1 IgG administered intranasally also prevented transmission, suggesting the importance of mucosal immunity in preventing influenza virus transmission. Collectively, our data indicate that IgG antibodies may prevent pathogenesis associated with influenza virus infection but do not protect from virus infection by airborne transmission, while IgA antibodies are more important for preventing transmission of influenza viruses. PMID:23698296

Polymorphisms in DC-SIGN and L-SIGN genes are associated with HIV-1 vertical transmission in a Northeastern Brazilian population.

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da Silva, Ronaldo Celerino; Segat, Ludovica; Zanin, Valentina; Arraes, Luiz Claudio; Crovella, Sergio

2012-11-01

DC-SIGN and L-SIGN are receptors expressed on specialized macrophages in decidua, (Hofbauer and placental capillary endothelial cells), known to interact with several pathogens, including HIV-1. To disclose the possible involvement of these molecules in the susceptibility to HIV vertical transmission, we analyzed DC-SIGN and L-SIGN gene single nucleotide polymorphisms (SNPs) in 192 HIV-1 positive children and 58 HIV-1 negative children all born to HIV-1 positive mothers, as well as 96 healthy uninfected children not exposed to HIV-1, all from Northeast Brazil. The frequency of three SNPs in the DC-SIGN promoter (-139G>A, -201G>T and -336A>G) were significantly different when comparing HIV positive children with HIV-1 exposed uninfected children, indicating an association with susceptibility to HIV-1 vertical transmission. This genetic association suggests that DC-SIGN molecule may play a role in susceptibility to HIV-1 infection through vertical transmission. Copyright © 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Effectiveness of interventions to prevent mother-to-child transmission of HIV in Southern Ethiopia

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Merdekios B

2011-11-01

Full Text Available Behailu Merdekios1, Adebola A Adedimeji2 1College of Medicine and Health Sciences, Arba Minch University, Ethiopia; 2Albert Einstein College of Medicine, Jack and Pearl Resnick Campus, New York, USA Background: In Ethiopia, Progress in Reducing Mother-to-Child-Transmission (PMTCT of human immunodeficiency virus (HIV is being curtailed by behavioral and cultural factors that continue to put unborn children at risk, and mother-to-child transmission is responsible for more than 90% of HIV infection in children. The objective of this study was to assess PMTCT services by examining knowledge about reducing vertical transmission among pregnant women. Methods: A multistaged sampling institution-based survey was conducted in 113 pregnant women in Arba Minch. Qualitative and quantitative data were obtained. Results: Of the 113 respondents, 89.4% were from Arba Minch, 43.4% were at least 25 years of age, 73.4% had formal education at primary level or above, 100% reported acceptance of voluntary counseling and testing, 92.0% were knowledgeable about mother-to-child transmission, and 90.3% were aware of the availability of the PMTCT service in the health facility. Of 74 HIV-positive women in PMTCT, only three (4.1% had had skilled birth attendants at delivery. There was an unacceptable degree of loss of women from PMTCT. Maternal educational level had a statistical association with income (P < 0.001 and voluntary counseling and testing for pregnant women (P < 0.05. Factors that determined use of PMTCT included culture, socioeconomic status, and fear of stigma and discrimination. Conclusion: In the area studied, intervention to reduce mother-to-child transmission of HIV is failing to reach its goal. This is an alarming discovery requiring quick reconsideration and strengthening of preventive strategies at all levels. Keywords: human immunodeficiency virus, mother-to-child transmission, pregnant women, Ethiopia

Evaluation of preventive measures for mother-to-child transmission of HIV in Aracaju, State of Sergipe, Brazil

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Lígia Mara Dolce de Lemos

2012-12-01

Full Text Available INTRODUCTION: The main route of human immunodeficiency virus (HIV infection in children is from mother to child. The preventive measures established for the Aids Clinical Trial Group protocol 076 (ACTG 076 significantly reduces HIV vertical transmission rates. This study aims to evaluate the implementation of the ACTG 076 protocol in the maternity units of State of Sergipe, Brazilian northeast. METHODS: This is a descriptive, retrospective study with a quantitative approach, with HIV positive women and children exposed, attending a Maternity reference for high-risk pregnancies. Data were obtained from patient records registered in the years 1994 to 2010. RESULTS: Amongst the 110 pregnant women and exposed newborns, the ACTG 076 protocol was fully utilized in only 31.8% of the participants. During the prenatal period, zidovudine (ZDV was taken by 79.1% of the pregnant women. Only 49.1% of HIV seropositive patients used ZDV during delivery. Two (1.8% children were considered infected and 50 (45.5% do not have a conclusive diagnosis to date. CONCLUSIONS: There were significant deficiencies in the prevention of mother-to-child transmission of HIV, including lack of compliance with the three phases of the ACTG 076 protocol; inadequacies in prenatal care; inappropriate mode of delivery and lack of adequate follow up of exposed children.

Expectations of vertical transmission of hiv from HIV-infected mothers in a research process at Sorocaba/SP

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Danilo de Assis Pereira; Denise Moraes Horiy; Evelise de Oliveira Proença; Acácio Sidinei Almeida Santos

2014-01-01

ABSTRACT Introduction: Vertical transmission of AIDS is defined as a transmission that occurs from mother to child during pregnancy, birth or breastfeeding and is today the main route of HIV infection in children under 13 in the world. Objective: in order to understand the history of life and the therapeutic itinerary of HIV positive pregnant women, it was conducted a study with a qualitative approach to social phenomenology as theoretical and methodological references. Methods: For the st...

Molecular characteristics of Streptococcus agalactiae in a mother-baby prospective cohort study: Implication for vaccine development and insights into vertical transmission.

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Li, Shunming; Wen, Guoming; Cao, Xuelian; Guo, Dan; Yao, Zhenjiang; Wu, Chuan'an; Ye, Xiaohua

2018-04-05

Streptococcus agalactiae (GBS) is a leading cause of neonatal sepsis and meningitis in many countries. This study aimed to determine the molecular characteristics of GBS colonized in mothers and their infants so as to provide implication for vaccine strategies and confirm vertical transmission. A prospective cohort study was conducted to recruit 1815 mother-neonate pairs. All GBS isolates from pregnant women and her infants were tested for serotypes, multilocus sequence types and virulence genes. The relationship between multiple molecular characteristics of GBS isolates was tested by the correspondence analysis, and the agreement between mother-neonate paired data in molecular characteristics was analyzed using Kappa tests. The predominant serotypes were III, Ia and V, and the most prevalent sequence types (STs) were ST19, ST17, ST10, and ST12. All isolates carried at least one pilus island (PI). The most common combination of PIs was PI-2b alone, followed by PI-1+PI-2a and PI-2a alone, and the most prevalent alpha-like protein (alp) genes were rib, epsilon and alphaC. Moreover, a strong relationship was noted between STs, serotypes, alp genes and PIs, including ST17 associated with serotype-III/rib/PI-2b, ST19 with serotype-III/rib/PI-1+PI-2a, and ST485 with serotype-Ia/epsilon/PI-2b. The rate of GBS vertical transmission was 14.1%, and the kappa test revealed good agreement in multiple molecular characteristics among GBS-positive mother-neonate pairs. Notably, the switching of molecular characteristics was found during vertical transmission. Our findings underscore the value of monitoring multiple molecular characteristics so as to provide implication for multivalent strategies and gain insights into GBS vertical transmission and vertical characteristic switching. Copyright © 2018 Elsevier Ltd. All rights reserved.

Vector independent transmission of the vector-borne bluetongue virus.

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van der Sluijs, Mirjam Tineke Willemijn; de Smit, Abraham J; Moormann, Rob J M

2016-01-01

Bluetongue is an economically important disease of ruminants. The causative agent, Bluetongue virus (BTV), is mainly transmitted by insect vectors. This review focuses on vector-free BTV transmission, and its epizootic and economic consequences. Vector-free transmission can either be vertical, from dam to fetus, or horizontal via direct contract. For several BTV-serotypes, vertical (transplacental) transmission has been described, resulting in severe congenital malformations. Transplacental transmission had been mainly associated with live vaccine strains. Yet, the European BTV-8 strain demonstrated a high incidence of transplacental transmission in natural circumstances. The relevance of transplacental transmission for the epizootiology is considered limited, especially in enzootic areas. However, transplacental transmission can have a substantial economic impact due to the loss of progeny. Inactivated vaccines have demonstrated to prevent transplacental transmission. Vector-free horizontal transmission has also been demonstrated. Since direct horizontal transmission requires close contact of animals, it is considered only relevant for within-farm spreading of BTV. The genetic determinants which enable vector-free transmission are present in virus strains circulating in the field. More research into the genetic changes which enable vector-free transmission is essential to better evaluate the risks associated with outbreaks of new BTV serotypes and to design more appropriate control measures.

Melanotic pathology and vertical transmission of the gut commensal Elizabethkingia meningoseptica in the major malaria vector Anopheles gambiae.

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Idir G Akhouayri

Full Text Available The resident gut flora is known to have significant impacts on the life history of the host organism. Endosymbiotic bacterial species in the Anopheles mosquito gut are potent modulators of sexual development of the malaria parasite, Plasmodium, and thus proposed as potential control agents of malaria transmission.Here we report a melanotic pathology in the major African malaria vector Anopheles gambiae, caused by the dominant mosquito endosymbiont Elizabethkingiameningoseptica. Transfer of melanised tissues into the haemolymph of healthy adult mosquitoes or direct haemolymph inoculation with isolated E. meningoseptica bacteria were the only means for transmission and de novo formation of melanotic lesions, specifically in the fat body tissues of recipient individuals. We show that E. meningoseptica can be vertically transmitted from eggs to larvae and that E. meningoseptica-mono-associated mosquitoes display significant mortality, which is further enhanced upon Plasmodium infection, suggesting a synergistic impact of E. meningoseptica and Plasmodium on mosquito survival.The high pathogenicity and permanent association of E. meningoseptica with An. Gambiae through vertical transmission constitute attractive characteristics towards the potential design of novel mosquito/malaria biocontrol strategies.

Prevalência de HIV em gestantes e transmissão vertical segundo perfil socioeconômico, Vitória, ES Factores asociados a recidiva en hanseníasis en Mato Grosso, Centro-oeste de Brasil HIV prevalence in pregnant women and vertical transmission in according to socioeconomic status, Southeastern Brazil

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Anne Caroline Barbosa Cerqueira Vieira

2011-08-01

Full Text Available OBJETIVO: Descrever a prevalência de infecção por HIV em gestantes e a taxa de transmissão vertical, segundo o perfil socioeconômico dos bairros de residência das mães. MÉTODOS: Estudo ecológico exploratório utilizando a base de dados do Sistema de Informação de Agravos de Notificação de gestantes HIV-positivas e aids em crianças notificadas entre 2000 e 2006 em Vitória, ES. Para análise das informações socioeconômicas foi utilizado o Índice de Qualidade Urbana. A prevalência de HIV em gestantes e a taxa de transmissão vertical foram calculadas. A distribuição espacial dos casos foi realizada no programa Terraview 3.2.0. Para verificar a associação entre a qualidade urbana e a prevalência de HIV em gestantes utilizou-se o modelo de regressão de Poisson. RESULTADOS: Um total de 137 gestantes e 14 crianças infectadas por transmissão vertical foi notificado no período. Sete crianças correspondiam a mães HIV-positivas sem notificação de caso no período analisado. A prevalência de infecção em gestantes no período foi de 0,44% e a taxa de transmissão vertical foi de 9,7%. CONCLUSÕES: A prevalência de infecção por HIV em gestantes e a transmissão vertical associam-se à qualidade urbana do bairro de residência, indicando que os bairros com menor qualidade urbana devem ser priorizados quanto às ações para redução da transmissão vertical.OBJETIVO: Analizar factores asociados a la ocurrencia de recidiva en hanseníasis. MÉTODOS: Estudio retrospectivo caso-control con 159 pacientes mayores de 15 años diagnosticados con hanseníasis en cinco municipios del Estado de Mato Grosso, Centro-oeste de Brasil, cuyas unidades de salud eran consideradas de referencia para el atendimiento. El grupo de casos incluyó 53 individuos con recidiva de 2005 a 2007 y fue comparado con el grupo control (106 con alta por cura en 2005, pareados por sexo y clasificación operacional. Se usaron datos del Sistema de Informaci

Evidence of vertical transmission and tissue tropism of Streptococcosis from naturally infected red tilapia (Oreochromis spp.

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Padmaja Jayaprasad Pradeep

2016-05-01

Full Text Available Streptococcosis is a highly problematic disease in the aquaculture of freshwater fishes, especially for tilapia. The possibility of vertical transmission of streptococcosis and the pattern of tissue tropism of this pathogen in various organs was examined in red tilapia (Oreochromis sp.. Healthy broodstock without any clinical signs of Streptococcus spp. were selected from a farm earlier reported to have the disease and a total of 10 pairs were forced spawned to provide samples of gametes and progeny for pathogen testing. A colorimetric LAMP assay was used to confirm whether the bacterial pathogens Streptococcus. agalactiae and Streptococcus. iniae was present in samples of milt, unfertilized eggs, fertilized eggs, and offspring at various stages of development, as well as internal organs of broodstock (reproductive organs, gill, liver, spleen, kidney and brain as well as samples of water from culture systems. The majority of samples of milt (9/10 and unfertilized eggs (7/10 collected from the broodstock were infected with S. iniae at the time of spawning and was transmitted to all of their offspring. Nevertheless, when the same samples of gametes were analyzed for S. agalactiae, they were all found to be negative but the pathogen was found to be present in some 10-day-old larval offspring (4/10. However, when the pathogenic presence was analyzed from the reproductive organs of the parents, both S. agalactiae (11/20 and S. iniae (18/20 bacterium were common. Although, all broodstock were asymptomatic, almost all broodstock harboured the bacteria in many organs. Confirmation of vertical transmission of streptococcosis in tilapia means that intergenerational break cannot be used as a reliable and simple means of reducing or eliminating the prevalence of these difficult pathogens in aquaculture stock. Keywords: Tilapia, Vertical transmission, Specific pathogen free, Streptococcus, Tissue tropism

Risk adapted transmission prophylaxis to prevent vertical HIV–1 transmission: Effectiveness and safety of an abbreviated regimen of postnatal oral Zidovudine

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Neubert Jennifer

2013-01-01

Full Text Available Abstract Background Antiretroviral drugs including zidovudine (ZDV are effective in reducing HIV mother to child transmission (MTCT, however safety concern remains. The optimal duration of postnatal ZDV has not been established in clinical studies and there is a lack of consensus regarding optimal management. The objective of this study was to investigate the effectiveness and safety of a risk adapted two week course of oral postnatal ZDV as part of a combined intervention to reduce MTCT. Methods 118 mother infant pairs were treated according to the German-Austrian recommendations for HIV therapy in pregnancy and in HIV exposed newborns between 2000–2010. In the absence of factors associated with an increased HIV–1 transmission risk, children were assigned to the low risk group and treated with an abbreviated postnatal regimen with oral ZDV for 2 weeks. In the presence of risk factors, postnatal ZDV was escalated accordingly. Results Of 118 mother-infant pairs 79 were stratified to the low risk group, 27 to the high risk group and 11 to the very high risk group for HIV–1 MTCT. 4 children were lost to follow up. Overall Transmission risk in the group regardless of risk factors and completion of prophylaxis was 1.8% (95% confidence interval (CI 0.09–6.6. If transmission prophylaxis was complete, transmission risk was 0.9% (95% CI 0.01-5.7. In the low risk group receiving two week oral ZDV transmission risk was 1.4% (95% CI 0.01–8.4 Conclusion These data demonstrate the effectiveness of a short neonatal ZDV regimen in infants of women on stable ART and effective HIV–1 suppression. Further evaluation is needed in larger studies.

HIV prevention and transmission myths among heterosexually active adults in low-income areas of South Florida.

Science.gov (United States)

Beck, Dano W; Lalota, Marlene; Metsch, Lisa R; Cardenas, Gabriel A; Forrest, David W; Lieb, Spencer; Liberti, Thomas M

2012-04-01

Misconceptions about HIV transmission and prevention may inhibit individuals' accurate assessment of their level of risk. We used venue-based sampling to conduct a cross-sectional study of heterosexually active adults (N = 1,221) within areas exhibiting high poverty and HIV/AIDS rates in Miami-Dade and Broward counties in 2007. Two logistic regression analyses identified correlates of holding inaccurate beliefs about HIV transmission and prevention. Belief in incorrect HIV prevention methods (27.2%) and modes of transmission (38.5%) was common. Having at least one incorrect prevention belief was associated with being Hispanic compared to white (non-Hispanic), being depressed, and not knowing one's HIV status. Having at least one incorrect transmission belief was associated with being younger, heavy alcohol use, being depressed, not having seen a physician in the past 12 months, and not knowing one's HIV status. Among low-income heterosexuals, HIV prevention and transmission myths are widespread. Debunking them could have HIV prevention value.

HIV-1 transmission linkage in an HIV-1 prevention clinical trial

Energy Technology Data Exchange (ETDEWEB)

Leitner, Thomas [Los Alamos National Laboratory; Campbell, Mary S [UNIV OF WASHINGTON; Mullins, James I [UNIV OF WASHINGTON; Hughes, James P [UNIV OF WASHINGTON; Wong, Kim G [UNIV OF WASHINGTON; Raugi, Dana N [UNIV OF WASHINGTON; Scrensen, Stefanie [UNIV OF WASHINGTON

2009-01-01

HIV-1 sequencing has been used extensively in epidemiologic and forensic studies to investigate patterns of HIV-1 transmission. However, the criteria for establishing genetic linkage between HIV-1 strains in HIV-1 prevention trials have not been formalized. The Partners in Prevention HSV/HIV Transmission Study (ClinicaITrials.gov NCT00194519) enrolled 3408 HIV-1 serodiscordant heterosexual African couples to determine the efficacy of genital herpes suppression with acyclovir in reducing HIV-1 transmission. The trial analysis required laboratory confirmation of HIV-1 linkage between enrolled partners in couples in which seroconversion occurred. Here we describe the process and results from HIV-1 sequencing studies used to perform transmission linkage determination in this clinical trial. Consensus Sanger sequencing of env (C2-V3-C3) and gag (p17-p24) genes was performed on plasma HIV-1 RNA from both partners within 3 months of seroconversion; env single molecule or pyrosequencing was also performed in some cases. For linkage, we required monophyletic clustering between HIV-1 sequences in the transmitting and seroconverting partners, and developed a Bayesian algorithm using genetic distances to evaluate the posterior probability of linkage of participants sequences. Adjudicators classified transmissions as linked, unlinked, or indeterminate. Among 151 seroconversion events, we found 108 (71.5%) linked, 40 (26.5%) unlinked, and 3 (2.0%) to have indeterminate transmissions. Nine (8.3%) were linked by consensus gag sequencing only and 8 (7.4%) required deep sequencing of env. In this first use of HIV-1 sequencing to establish endpoints in a large clinical trial, more than one-fourth of transmissions were unlinked to the enrolled partner, illustrating the relevance of these methods in the design of future HIV-1 prevention trials in serodiscordant couples. A hierarchy of sequencing techniques, analysis methods, and expert adjudication contributed to the linkage

conference report prevention of mother-to-child transmission

African Journals Online (AJOL)

2004-08-02

Aug 2, 2004 ... prevention of mother-to-child transmission (PMTCT) of. HIV1 were presented at an evening satellite session. ... They complement other guidelines on treatment issued by the WHO and the 3 by 5 Initiative. ..... Further work on infant feeding and programmatic experiences added to the knowledge base.

Prevention of mother to child transmission of HIV/AIDS in Eritrea: the ...

African Journals Online (AJOL)

Objective: The objective of this study was to assess the use of IMCI guidelines in children presenting with diarrhea at Ghindae Hospital. Methods: The ... guidelines, the rates of vertically transmission of HIV/. AIDS has been decimated to less ... to assess the effect of PMTCT by comparing the data before the start of PMTCT in ...

Prevalence, genetic identity and vertical transmission of Babesia microti in three naturally infected species of vole, Microtus spp. (Cricetidae).

Science.gov (United States)

Tołkacz, Katarzyna; Bednarska, Małgorzata; Alsarraf, Mohammed; Dwużnik, Dorota; Grzybek, Maciej; Welc-Falęciak, Renata; Behnke, Jerzy M; Bajer, Anna

2017-02-06

Vertical transmission is one of the transmission routes for Babesia microti, the causative agent of the zoonotic disease, babesiosis. Congenital Babesia invasions have been recorded in laboratory mice, dogs and humans. The aim of our study was to determine if vertical transmission of B. microti occurs in naturally-infected reservoir hosts of the genus Microtus. We sampled 124 common voles, Microtus arvalis; 76 root voles, M. oeconomus and 17 field voles, M. agrestis. In total, 113 embryos were isolated from 20 pregnant females. Another 11 pregnant females were kept in the animal house at the field station in Urwitałt until they had given birth and weaned their pups (n = 62). Blood smears and/or PCR targeting the 550 bp 18S rRNA gene fragment were used for the detection of B. microti. Selected PCR products, including isolates from females/dams and their embryos/pups, were sequenced. Positive PCR reactions were obtained for 41% (89/217) of the wild-caught voles. The highest prevalence of B. microti was recorded in M. arvalis (56/124; 45.2%), then in M. oeconomus (30/76; 39.5%) and the lowest in M. agrestis (3/17; 17.7%). Babesia microti DNA was detected in 61.4% (27/44) of pregnant females. Vertical transmission was confirmed in 81% (61/75) of the embryos recovered from Babesia-positive wild-caught pregnant females. The DNA of B. microti was detected in the hearts, lungs and livers of embryos from 98% of M. arvalis, 46% of M. oeconomus and 0% of M. agrestis embryos from Babesia-positive females. Of the pups born in captivity, 90% were born to Babesia-positive dams. Babesia microti DNA was detected in 70% (35/50) of M. arvalis and 83% (5/6) of M. oeconomus pups. Congenitally acquired infections had no impact on the survival of pups over a 3-week period post partum. Among 97 B. microti sequences, two genotypes were found. The IRU1 genotype (Jena-like) was dominant in wild-caught voles (49/53; 92%), pregnant females (9/11; 82%) and dams (3/5; 60%). The IRU2

Vertical Integration, Monopoly, and the First Amendment.

Science.gov (United States)

Brennan, Timothy J.

This paper addresses the relationship between the First Amendment, monopoly of transmission media, and vertical integration of transmission and content provision. A survey of some of the incentives a profit-maximizing transmission monopolist may have with respect to content is followed by a discussion of how vertical integration affects those…

Deeply-etched micromirror with vertical slit and metallic coating enabling transmission-type optical MEMS filters

Science.gov (United States)

Othman, Muhammad A.; Sabry, Yasser M.; Sadek, Mohamed; Nassar, Ismail M.; Khalil, Diaa A.

2016-03-01

In this work we report a novel optical MEMS deeply-etched mirror with metallic coating and vertical slot, where the later allows reflection and transmission by the micromirror. The micromirror as well as fiber grooves are fabricated using deep reactive ion etching technology, where the optical axis is in-plane and the components are self-aligned. The etching depth is 150 μm chosen to improve the micromirror optical throughput. The vertical optical structure is Al metal coated using the shadow mask technique. A fiber-coupled Fabry-Pérot filter is successfully realized using the fabricated structure. Experimental measurements were obtained based on a dielectric-coated optical fiber inserted into a fiber groove facing the slotted micromirror. A versatile performance in terms of the free spectral range and 3-dB bandwidth is achieved.

[Perinatal HIV transmission prophylaxis in the Liege region].

Science.gov (United States)

Jacquet, Y; Hoyoux, C; Dresse, M F

1998-08-01

In Liège, since February 1994, Protocole ACTG 076 has been followed for prevention of perinatal transmission of VIH. The pregnant women are treated by AZT during pregnancy and delivery. The newborn is also treated during 6 weeks. Following this treatment strategy, vertical transmission rate of VIH has dropped from 25.6% to 8.7%. The PCR is particulary promising for the early detection of infection in newborn, but definitive conclusion about infective status of the newborn can't be done during the first week of life. The potential role of intrapartum transmission is now under evaluation in the hope to establish the safest mode of delivery.

Perfil clínico-laboratorial de crianças vivendo com HIV/AIDS por transmissão vertical em uma cidade do Nordeste brasileiro Clinical and laboratory profile of children living with vertically transmitted HIV/AIDS in a city in northeastern Brazily

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Margareth Jamil Maluf e Silva

2010-02-01

Full Text Available INTRODUÇÃO: a transmissão vertical constitui a principal via de infecção infantil pelo vírus HIV-1 (vírus da imunodeficiência humana. A presente pesquisa tem como objetivo estudar a evolução clínica e laboratorial de crianças vivendo com HIV/AIDS decorrente da transmissão vertical. MÉTODOS: trata-se de um estudo descritivo, retrospectivo, realizado a partir da coleta de dados em prontuário médico de todas as crianças atendidas em um Serviço de Assistência Especializada, no período de janeiro de 1998 a junho de 2006. RESULTADOS: foram avaliadas 80 crianças que preencheram critérios de inclusão. Observou-se que em 56 (70% crianças, o diagnóstico da infecção pelo HIV na mãe deu-se após o parto e que em 44 (55% o parto foi via vaginal. Amamentação ao seio materno foi documentada em 56 (70% crianças e esta variou de um mês até mais de 12 meses. A não utilização ou uso incompleto do Protocolo ACTG 076 foi documentado em 63 (78,5% casos. CONCLUSÕES: os dados observados em nosso estudo são bastante preocupantes e revelam falha na assistência materno-infantil, especialmente voltada para prevenção da transmissão.INTRODUCTION: Vertical transmission constitutes the main route for child infection by the HIV-1 virus (human immune deficiency virus. This study aimed to investigate the clinical and laboratory evolution of children with vertically transmitted HIV/AIDS. METHODS: This was a retrospective descriptive study based on data gathered from the medical records of all the children who were seen at a specialized care unit between January 1998 and June 2006. RESULTS: Eighty children who met the inclusion criteria were evaluated. In the cases 56 (70% of the children, their mothers were diagnosed as HIV-positive after childbirth. The delivery was vaginal for 44 (55% of the children. Fifty-six children (70% were breastfed by their mothers for periods ranging from one to more than 12 months. Failure to use or incomplete

Cultural macroevolution on neighbor graphs : vertical and horizontal transmission among Western North American Indian societies.

Science.gov (United States)

Towner, Mary C; Grote, Mark N; Venti, Jay; Borgerhoff Mulder, Monique

2012-09-01

What are the driving forces of cultural macroevolution, the evolution of cultural traits that characterize societies or populations? This question has engaged anthropologists for more than a century, with little consensus regarding the answer. We develop and fit autologistic models, built upon both spatial and linguistic neighbor graphs, for 44 cultural traits of 172 societies in the Western North American Indian (WNAI) database. For each trait, we compare models including or excluding one or both neighbor graphs, and for the majority of traits we find strong evidence in favor of a model which uses both spatial and linguistic neighbors to predict a trait's distribution. Our results run counter to the assertion that cultural trait distributions can be explained largely by the transmission of traits from parent to daughter populations and are thus best analyzed with phylogenies. In contrast, we show that vertical and horizontal transmission pathways can be incorporated in a single model, that both transmission modes may indeed operate on the same trait, and that for most traits in the WNAI database, accounting for only one mode of transmission would result in a loss of information.

The transmission of vertical vibration through seats: Influence of the characteristics of the human body

Science.gov (United States)

Toward, Martin G. R.; Griffin, Michael J.

2011-12-01

The transmission of vibration through a seat depends on the impedance of the seat and the apparent mass of the seat occupant. This study was designed to determine how factors affecting the apparent mass of the body (age, gender, physical characteristics, backrest contact, and magnitude of vibration) affect seat transmissibility. The transmission of vertical vibration through a car seat was measured with 80 adults (41 males and 39 females aged 18-65) at frequencies between 0.6 and 20 Hz with two backrest conditions (no backrest and backrest), and with three magnitudes of random vibration (0.5, 1.0, and 1.5 m s -2 rms). Linear regression models were used to study the effects of subject physical characteristics (age, gender, and anthropometry) and features of their apparent mass (resonance frequency, apparent mass at resonance and at 12 Hz) on the measured seat transmissibility. The strongest predictor of both the frequency of the principal resonance in seat transmissibility and the seat transmissibility at resonance was subject age, with other factors having only marginal effects. The transmissibility of the seat at 12 Hz depended on subject age, body mass index, and gender. Although subject weight was strongly associated with apparent mass, weight was not strongly associated with seat transmissibility. The resonance frequency of the seat decreased with increases in the magnitude of the vibration excitation and increased when subjects made contact with the backrest. Inter-subject variability in the resonance frequency and transmissibility at resonance was less with greater vibration excitation, but was largely unaffected by backrest contact. A lumped parameter seat-person model showed that changes in seat transmissibility with age can be predicted from changes in apparent mass with age, and that the dynamic stiffness of the seat appeared to increase with increased loading so as to compensate for increases in subject apparent mass associated with increased sitting

Evidence of environmental and vertical transmission of Burkholderia symbionts in the oriental chinch bug, Cavelerius saccharivorus (Heteroptera: Blissidae).

Science.gov (United States)

Itoh, Hideomi; Aita, Manabu; Nagayama, Atsushi; Meng, Xian-Ying; Kamagata, Yoichi; Navarro, Ronald; Hori, Tomoyuki; Ohgiya, Satoru; Kikuchi, Yoshitomo

2014-10-01

The vertical transmission of symbiotic microorganisms is omnipresent in insects, while the evolutionary process remains totally unclear. The oriental chinch bug, Cavelerius saccharivorus (Heteroptera: Blissidae), is a serious sugarcane pest, in which symbiotic bacteria densely populate the lumen of the numerous tubule-like midgut crypts that the chinch bug develops. Cloning and sequence analyses of the 16S rRNA genes revealed that the crypts were dominated by a specific group of bacteria belonging to the genus Burkholderia of the Betaproteobacteria. The Burkholderia sequences were distributed into three distinct clades: the Burkholderia cepacia complex (BCC), the plant-associated beneficial and environmental (PBE) group, and the stinkbug-associated beneficial and environmental group (SBE). Diagnostic PCR revealed that only one of the three groups of Burkholderia was present in ∼89% of the chinch bug field populations tested, while infections with multiple Burkholderia groups within one insect were observed in only ∼10%. Deep sequencing of the 16S rRNA gene confirmed that the Burkholderia bacteria specifically colonized the crypts and were dominated by one of three Burkholderia groups. The lack of phylogenetic congruence between the symbiont and the host population strongly suggested host-symbiont promiscuity, which is probably caused by environmental acquisition of the symbionts by some hosts. Meanwhile, inspections of eggs and hatchlings by diagnostic PCR and egg surface sterilization demonstrated that almost 30% of the hatchlings vertically acquire symbiotic Burkholderia via symbiont-contaminated egg surfaces. The mixed strategy of symbiont transmission found in the oriental chinch bug might be an intermediate stage in evolution from environmental acquisition to strict vertical transmission in insects. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Smart Transmission Grids - Benefits and Risks

Directory of Open Access Journals (Sweden)

Velasco-Ramírez E.

2013-01-01

Full Text Available Nowadays the Power Systems are working near their stability limits, for this reason it is necessary and essential a transition to new transmission systems that ensure efficient delivery of electrical energy, with the objective to prevent “blackouts” that causesignificant losses in the economy of any country in the world. This paper analyzes important elements to consider having a healthy and efficient transition from a power grid vertically integrated into a smart transmission grid. A comparative analysis in the model, development, benefits and risks of the implementation of these systems, between two of the main marc of references of smart grids, the EU and the USA is presented.

Prevention of mother-to-child transmission of HIV guidelines: Nurses ...

African Journals Online (AJOL)

Prevention of mother-to-child transmission of HIV guidelines: Nurses' views at four primary ... lifelong antiretroviral therapy (ART) for all HIV-positive pregnant women regardless of CD4 cell count. ... Data were analysed using thematic analysis.

Prevention of mother-to-child transmission of HIV: the Georgian experience.

Science.gov (United States)

Tsertsvadze, Tengiz; Kakabadze, Tea; Shermadini, Ketevan; Abutidze, Akaki; Karchava, Marika; Chkhartishvili, Nikoloz; Badridze, Nino; Bokhua, Zaza; Asatiani, Tengiz

2008-09-01

the 28th week of pregnancy only 1 child was infected. As of December 2007, 5 women are still pregnant. Three of them receive antiretroviral drugs (ARV) prophylaxis with AZT+3TC+SQV/r. Two women are under 28 weeks of gestational age. Over the last several years the national response to AIDS in Georgia achieved significant progress. The provision of comprehensive packages of PMTCT services in Georgia has been shown to minimize the risk of vertical transmission. As described above none of the women completing full course of ARV prophylaxis, combined with appropriate infant feeding, transmitted HIV to their children. PMTCT programmes are indisputably the main entry point not only for HIV related care and treatment for women, but also for other comprehensive care and prevention.

AIDS em gestantes: possibilidade de reduzir a transmissão vertical

Directory of Open Access Journals (Sweden)

Fernanda Scherer Wiethäuper

2003-06-01

Full Text Available Neste estudo, buscamos investigar o conhecimento que gestantes possuem sobre a transmissão vertical, o comprometimento do feto e o significado do resultado soropositivo que a identifica como infectada pelo HIV. A pesquisa exploratória, de natureza qualitativa, foi desenvolvida em Unidades Sanitárias de São Leopoldo/RS. A análise permitiu captar a percepção de 63 gestantes entre 16 e 40 anos sobre os motivos e os significados para realização do teste, os conhecimentos e vivências do cotidiano e as perspectivas e cuidados com o bebê. Os resultados trazem um alerta aos profissionais que atuam no pré-natal, visto que necessitam atender uma complexidade de situações que emergem quando se vincula gestação e AIDS.

Rift Valley fever virus: strategies for maintenance, survival and vertical transmission in mosquitoes.

Science.gov (United States)

Lumley, Sarah; Horton, Daniel L; Hernandez-Triana, Luis L M; Johnson, Nicholas; Fooks, Anthony R; Hewson, Roger

2017-05-01

Rift Valley fever virus (RVFV) is a mosquito-borne arbovirus causing severe disease in humans and ruminants. Spread of RVFV out of Africa has raised concerns that it could emerge in Europe or the USA. Virus persistence is dependent on successful infection of, replication in, and transmission to susceptible vertebrate and invertebrate hosts, modulated by virus-host and vector-virus interactions. The principal accepted theory for the long-term maintenance of RVFV involves vertical transmission (VT) of virus to mosquito progeny, with the virus surviving long inter-epizootic periods within the egg. This VT hypothesis, however, is yet to be comprehensively proven. Here, evidence for and against the VT of RVFV is reviewed along with the identification of factors limiting its detection in natural and experimental data. The observations of VT for other arboviruses in the genera Alphavirus, Flavivirus and Orthobunyavirus are discussed within the context of RVFV. The review concludes that VT of RVFV is likely but that current data are insufficient to irrefutably prove this hypothesis.

Illness during Pregnancy and Bacterial Vaginosis are Associated with In Utero HIV-1 Transmission

Science.gov (United States)

Farquhar, Carey; Mbori-Ngacha, Dorothy; Overbaugh, Julie; Wamalwa, Dalton; Harris, Jennifer; Bosire, Rose; John-Stewart, Grace

2009-01-01

HIV-1 transmission in utero accounts for 20–30% of vertical transmission events in breastfeeding populations. In a prospective study of 463 HIV-1-infected mothers and infants, illness during pregnancy was associated with 2.6-fold increased risk of in utero HIV-1 transmission (95% CI 1.2, 5.8) and bacterial vaginosis with a 3-fold increase (95% CI 1.0–7.0) after adjusting for maternal HIV-1 viral load. Interventions targeting these novel risk factors could lead to more effective prevention of transmission during pregnancy. PMID:19952542

Prevention of Mother-to-Child Transmission of HIV data ...

African Journals Online (AJOL)

2014-08-21

Aug 21, 2014 ... service delivery in the public health sector of South Africa .... professional nurse in charge of the PMTCT programme at ... 1. antenatal care (ANC) clients pre-test counselled for HIV ..... CD4, Cluster of differentiation; NVP, Nevirapine; PMTCT, prevention of mother-to-child transmission of HIV; DHIS, District.

Prevention of Mother-to-Child Transmission of HIV data ...

African Journals Online (AJOL)

Background: Even though significant progress has been made in the roll-out and quality of the prevention of mother-to-child transmission of HIV (PMTCT) services in South Africa, the quality of patient data recording remains a challenge. Objectives: To assess PMTCT data completeness and accuracy at primary healthcare ...

Scaling up Prevention of Mother to Child Transmission of HIV ...

African Journals Online (AJOL)

AJRH Managing Editor

Nigeria is scaling up prevention of mother-to-child transmission (PMTCT) of HIV interventions to primary health care ... Of 10,289 women who had antenatal HIV test, 74 had positive results. ..... counselling and lack of reinforcement of contents.

Prevention of mother-to-child transmission outcomes in the private ...

African Journals Online (AJOL)

Prevention of mother-to-child transmission outcomes in the private sector in central Durban. ... Median viral loads and CD4 counts were 11 391 copies/ml and 426 cells/μl, respectively. Eighty-six women ... Article Metrics ... HOW TO USE AJOL.

Hydraulic transmissivity determination for the groundwater exploration using vertical electric sounding method in comparison to the traditional methods

International Nuclear Information System (INIS)

Arshad, M.; Shakoor, A.; Ahmad, M.

2013-01-01

An important aquifer characteristic, transmissivity significantly contributes to the development of local and regional groundwater resources and solute transport management. Estimation of this property allows quantitative prediction of the hydraulic response and solute transport of the aquifer to recharge and pumping. This study presents the three techniques, used to compare transmissivity determination by Vertical Electric Sounding (VES) over the traditional techniques. The validation of VES was compared with the old widely used methods such as grain size distribution and pumping test techniques. Grain size distribution analysis was carried out to determine transmissivity. Pumping test was performed to determine transmissivity using the type curves solution for unconfined aquifer and taking into account the delayed yield. In resistivity imaging survey, the soil layers were detected through interpretation of resistivity data. Formation factor for each layer was determined with the relation of aquifer soil resistivity and ground water resistivity. The estimated transmissivities though grain size distribution, pumping test and resistivity survey were 0.588, 0.578 and 0.756m/sup 2//min, respectively. The results emphasized the potential of the resistivity survey for aquifer transmissivity determination. (author)

Comparative cost-effectiveness of Option B+ for prevention of mother-to-child transmission of HIV in Malawi.

Science.gov (United States)

Tweya, Hannock; Keiser, Olivia; Haas, Andreas D; Tenthani, Lyson; Phiri, Sam; Egger, Matthias; Estill, Janne

2016-03-27

To estimate the cost-effectiveness of prevention of mother-to-child transmission (MTCT) of HIV with lifelong antiretroviral therapy (ART) for pregnant and breastfeeding women ('Option B+') compared with ART during pregnancy or breastfeeding only unless clinically indicated ('Option B'). Mathematical modelling study of first and second pregnancy, informed by data from the Malawi Option B+ programme. Individual-based simulation model. We simulated cohorts of 10 000 women and their infants during two subsequent pregnancies, including the breastfeeding period, with either Option B+ or B. We parameterized the model with data from the literature and by analysing programmatic data. We compared total costs of antenatal and postnatal care, and lifetime costs and disability-adjusted life-years of the infected infants between Option B+ and Option B. During the first pregnancy, 15% of the infants born to HIV-infected mothers acquired the infection. With Option B+, 39% of the women were on ART at the beginning of the second pregnancy, compared with 18% with Option B. For second pregnancies, the rates MTCT were 11.3% with Option B+ and 12.3% with Option B. The incremental cost-effectiveness ratio comparing the two options ranged between about US$ 500 and US$ 1300 per DALY averted. Option B+ prevents more vertical transmissions of HIV than Option B, mainly because more women are already on ART at the beginning of the next pregnancy. Option B+ is a cost-effective strategy for PMTCT if the total future costs and lost lifetime of the infected infants are taken into account.

The Achilles’ heel of prevention to mother-to-child transmission of HIV: Protocol implementation, uptake, and sustainability

Science.gov (United States)

Rodriguez, Violeta J.; LaCabe, Richard P.; Privette, C. Kyle; Douglass, K. Marie; Peltzer, Karl; Matseke, Gladys; Mathebula, Audrey; Ramlagan, Shandir; Sifunda, Sibusiso; Prado, Guillermo “Willy”; Horigian, Viviana; Weiss, Stephen M.; Jones, Deborah L.

2017-01-01

Abstract The Joint United Nations Programme on HIV and AIDS proposed to reduce the vertical transmission of HIV from ∼72,200 to ∼8300 newly infected children by 2015 in South Africa (SA). However, cultural, infrastructural, and socio-economic barriers hinder the implementation of the prevention of mother-to-child transmission (PMTCT) protocol, and research on potential solutions to address these barriers in rural areas is particularly limited. This study sought to identify challenges and solutions to the implementation, uptake, and sustainability of the PMTCT protocol in rural SA. Forty-eight qualitative interviews, 12 focus groups discussions (n = 75), and one two-day workshop (n = 32 participants) were conducted with district directors, clinic leaders, staff, and patients from 12 rural clinics. The delivery and uptake of the PMTCT protocol was evaluated using the Consolidated Framework for Implementation Research (CFIR); 15 themes associated with challenges and solutions emerged. Intervention characteristics themes included PMTCT training and HIV serostatus disclosure. Outer-setting themes included facility space, health record management, and staff shortage; inner-setting themes included supply use and availability, staff–patient relationship, and transportation and scheduling. Themes related to characteristics of individuals included staff relationships, initial antenatal care visit, adherence, and culture and stigma. Implementation process themes included patient education, test results delivery, and male involvement. Significant gaps in care were identified in rural areas. Information obtained from participants using the CFIR framework provided valuable insights into solutions to barriers to PMTCT implementation. Continuously assessing and correcting PMTCT protocol implementation, uptake and sustainability appear merited to maximize HIV prevention. PMID:28922974

The Achilles' heel of prevention to mother-to-child transmission of HIV: Protocol implementation, uptake, and sustainability.

Science.gov (United States)

Rodriguez, Violeta J; LaCabe, Richard P; Privette, C Kyle; Douglass, K Marie; Peltzer, Karl; Matseke, Gladys; Mathebula, Audrey; Ramlagan, Shandir; Sifunda, Sibusiso; Prado, Guillermo Willy; Horigian, Viviana; Weiss, Stephen M; Jones, Deborah L

2017-12-01

The Joint United Nations Programme on HIV and AIDS proposed to reduce the vertical transmission of HIV from ∼72,200 to ∼8300 newly infected children by 2015 in South Africa (SA). However, cultural, infrastructural, and socio-economic barriers hinder the implementation of the prevention of mother-to-child transmission (PMTCT) protocol, and research on potential solutions to address these barriers in rural areas is particularly limited. This study sought to identify challenges and solutions to the implementation, uptake, and sustainability of the PMTCT protocol in rural SA. Forty-eight qualitative interviews, 12 focus groups discussions (n = 75), and one two-day workshop (n = 32 participants) were conducted with district directors, clinic leaders, staff, and patients from 12 rural clinics. The delivery and uptake of the PMTCT protocol was evaluated using the Consolidated Framework for Implementation Research (CFIR); 15 themes associated with challenges and solutions emerged. Intervention characteristics themes included PMTCT training and HIV serostatus disclosure. Outer-setting themes included facility space, health record management, and staff shortage; inner-setting themes included supply use and availability, staff-patient relationship, and transportation and scheduling. Themes related to characteristics of individuals included staff relationships, initial antenatal care visit, adherence, and culture and stigma. Implementation process themes included patient education, test results delivery, and male involvement. Significant gaps in care were identified in rural areas. Information obtained from participants using the CFIR framework provided valuable insights into solutions to barriers to PMTCT implementation. Continuously assessing and correcting PMTCT protocol implementation, uptake and sustainability appear merited to maximize HIV prevention.

Expectations of vertical transmission of hiv from HIV-infected mothers in a research process at Sorocaba/SP

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Danilo de Assis Pereira

2014-04-01

Introduction: Vertical transmission of AIDS is defined as a transmission that occurs from mother to child during pregnancy, birth or breastfeeding and is today the main route of HIV infection in children under 13 in the world. Objective: in order to understand the history of life and the therapeutic itinerary of HIV positive pregnant women, it was conducted a study with a qualitative approach to social phenomenology as theoretical and methodological references. Methods: For the study, a Likert-type questionnaire and a semi structured interview were applied for each participant. Results and Discussion: The study revealed the dilemmas faced and the actions taken by these women, HIV positive mothers, waiting for the diagnosis of the fetus, both participants in the Zero Vertical Transmission Program Clinic STD / AIDS in the city of Sorocaba, state of São Paulo. Prejudice and stigma related to AIDS is the leading source stressful and promoter of social isolation of this population, which faces the prejudice by relying mainly on their children and on their religiosity/spirituality as the second largest mainstay. Women often do not see their companion as supportive and fight back the situation of suffering, anguish, fear, and disappointment with their own courage and hope to overcome the adversity caused by the disease. Conclusion: The implications of this study suggest the risk and protective factors promoting resilience in this clientele, besides suggesting creating spaces that encourage discussion of the medical context, cultural, social and economic development in which these women are entered and that influence their daily decisions

Transmissão Vertical Zero: parceria entre o serviço público e o terceiro setor Transmisión Vertical Cero: sociedad entre el servicio público y el Tercer Sector Project Zero Perinatal HIV Transmission: partnership between public and private agencies

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Janie Maria de Almeida

2009-01-01

Full Text Available OBJETIVOS: Divulgar experiência multidisciplinar de parceria entre gestores da rede pública de saúde e organizações não-governamentais voltadas à atenção à gestante HIV positivo; e caracterizar as situações de exposição ao HIV por gestantes atendidas pelo Projeto Transmissão Vertical Zero do Município de Sorocaba - SP. MÉTODOS: Estudo retrospectivo com emprego de fontes documentais, e com levantamento de dados para caracterização sócio-demográfica e situações de exposição ao risco de infecção pelo HIV de 120 gestantes atendidas pelo Projeto, entre 1998 e 2004. RESULTADOS: O compartilhamento de ações entre o público e o terceiro setor constituiu-se em eficiente alternativa de assistência à mulher soropositiva para o HIV, ainda que 56,7% das gestantes desconhecessem a sorologia do parceiro e 73,3% nunca terem usado preservativo. CONCLUSÃO: A parceria contribuiu para a redução da transmissão vertical do HIV em Sorocaba - SP.OBJETIVOS: Divulgar la experiencia multidisciplinaria de sociedad entre gestores de la red pública de salud y organizaciones no gubernamentales dirigidas a la atención de la gestante VIH positivo; y caracterizar las situaciones de exposición al VIH por gestantes atendidas por el Proyecto Transmisión Vertical Zero del Municipio de Sorocaba - SP. MÉTODOS: Se trata de un estudio retrospectivo realizado con el empleo de fuentes documentales, y con el levantamiento de datos para caracterización socio-demográfica y situaciones de exposición al riesgo de infección por el VIH de 120 gestantes atendidas por el Proyecto, entre 1998 y 2004. RESULTADOS: El compartir acciones entre el público y el tercer sector se constituye en una eficiente alternativa de asistencia a la mujer seropositiva para el VIH, aunque el 56,7% de las gestantes desconociese la serología de la pareja y el 73,3% nunca haya usado preservativo. CONCLUSIÓN: La sociedad contribuyó a la reducción de la transmisión vertical

Preventing HIV transmission in chinese internal migrants: A behavioral approach

NARCIS (Netherlands)

X. Liu (Xiaona); V. Erasmus (Vicky); X. Sun (Xinying); R. Cai (Rui); Y. Shi (Yuhui); J.H. Richardus (Jan Hendrik)

2014-01-01

textabstractThis study is a step towards a behavioral intervention to prevent HIV transmission among Chinese internal migrants. To explore important and changeable determinants of condom use and inspect effective and feasible methods to increase condom use for the target population, we conducted a

Transmission XMCD-PEEM imaging of an engineered vertical FEBID cobalt nanowire with a domain wall

Science.gov (United States)

Wartelle, A.; Pablo-Navarro, J.; Staňo, M.; Bochmann, S.; Pairis, S.; Rioult, M.; Thirion, C.; Belkhou, R.; de Teresa, J. M.; Magén, C.; Fruchart, O.

2018-01-01

Using focused electron-beam-induced deposition, we fabricate a vertical, platinum-coated cobalt nanowire with a controlled three-dimensional structure. The latter is engineered to feature bends along the height: these are used as pinning sites for domain walls, which are obtained at remanence after saturation of the nanostructure in a horizontally applied magnetic field. The presence of domain walls is investigated using x-ray magnetic circular dichroism (XMCD) coupled to photoemission electron microscopy (PEEM). The vertical geometry of our sample combined with the low incidence of the x-ray beam produce an extended wire shadow which we use to recover the wire’s magnetic configuration. In this transmission configuration, the whole sample volume is probed, thus circumventing the limitation of PEEM to surfaces. This article reports on the first study of magnetic nanostructures standing perpendicular to the substrate with XMCD-PEEM. The use of this technique in shadow mode enabled us to confirm the presence of a domain wall without direct imaging of the nanowire.

A test of vertical economies for non-vertically integrated firms: The case of rural electric cooperatives

International Nuclear Information System (INIS)

Greer, Monica L.

2008-01-01

This paper seeks to evaluate unrealized economies of vertical integration for rural electric cooperatives. Given the well-established network economies that are inherent in the generation, transmission, and distribution of electricity, the coops long-standing choice of market structure is questionable (especially if their strategy is welfare maximization). Organized as either generation-and-transmission or distribution-only, the traditional measures of vertical economies will not work. Thus, I have devised an alternative method by which to measure such economies and find that, on average, cost savings in excess of 39% could have been realized had the coops adopted a vertically integrated structure. (author)

Knowledge and beliefs of international travellers about the transmission and prevention of HIV infection.

Science.gov (United States)

Allard, R; Lambert, G

1992-02-01

To measure the perceived risk of acquired immunodeficiency syndrome (AIDS) among international travellers, to measure their knowledge of the transmission and prevention of HIV infection abroad and to identify some of the determinants of this knowledge. Survey. Travellers' immunization clinic providing mostly primary preventive care to international travellers. All clients aged 18 to 50 years seen at the clinic between Oct. 2 and Dec. 21, 1989, before their departure. Sixteen statements measured knowledge of transmission and prevention of HIV infection. Standardized scales measured health beliefs. The response rate was 81% (331/409). Compared with other diseases AIDS was perceived to be associated with a low risk except by those travelling to countries with a high prevalence of AIDS. Most of the clients were found to have a good knowledge of HIV transmission to travellers, although some myths remained popular and some real routes of transmission, especially blood, remained underrated. In all, 70% of the subjects believed in the efficacy of condoms when used with local people, as compared with 79% when used with other tourists; this difference was greatest among travellers who perceived AIDS as being particularly severe but difficult to prevent. The determinants of the knowledge of HIV transmission and prevention were a high level of education, a mother tongue other than French, unmarried status, a high prevalence of AIDS at the destination, the duration of the trip and a high perceived risk of HIV infection. Counselling should teach travellers (a) not to underestimate their risk of HIV infection during their trip, (b) to decrease the risk of requiring health care in developing countries and (c) to rely on their own prudent sexual behaviour rather than on their assessment of the level of risk posed by the environment.

Transmissão vertical do HIV: expectativas e ações da gestante soropositiva Transmisión vertical del VHI: expectativas y acciones de la gestante seropositiva HIV perinatal transmission: expectations and actions of hiv-positive pregnant women

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Edilene Lins de Moura

2006-06-01

Full Text Available Este estudo descritivo, com abordagem qualitativa, foi motivado pelo elevado número de casos de transmissão vertical do HIV. Teve como objetivo identificar as expectativas e ações da gestante HIV positivo quanto à gravidez e ao concepto. A amostra constituiu-se de 14 gestantes infectadas, assintomáticas, que conheciam sua soropositividade antes da gravidez e que estavam no 3º trimestre de gestação. Utilizou-se entrevista para a coleta de dados que ocorreu em 2001 e 2002. Empregou-se o Método do Discurso do Sujeito Coletivo para analisar os dados. Verificou-se que, quanto à maternidade, as gestantes tinham expectativas semelhantes, adaptaram-se à gravidez, e acreditavam na soronegatividade do bebê e na efetividade do tratamento. Concluiu-se pela necessidade de implementação de orientação para a saúde direcionada à mulher com enfoque na transmissão vertical do HIV/aids.Este estudio descriptivo, con aproximación cualitativa, fue motivado por el gran número de niños con transmisión vertical del VHI. Tuvo como objetivo identificar las expectativas y acciones de la gestante VHI positivo en cuanto al embarazo y al concepto. La muestra se constituyó de 14 gestantes infectadas, asintomáticas, que conocían su seropositividad antes del embarazo y que estaban en el 3.er trimestre de gestación. Para la recolección de los datos, realizada en el período de 2001 y 2002, se utilizó la entrevista. El Método de Discurso de Sujeto Colectivo fue empleado para analizar los datos. Se verificó que, en cuanto a la maternidad, las gestantes tenían expectativas semejantes. Se adaptaron a la gestación, confiaban en que el bebé seria suero negativo y en la efectividad del tratamiento realizado. Las conclusiones orientan hacia la necesidad de implementación de orientación sobre la salud de la mujer con acercamiento en la transmisión vertical del VHI/SIDA.This descriptive study with a qualitative approach was motivated by the high number

Prevention of Mother-to-Child HIV Transmission: Predictors of Utilization & Future Policy Implication

OpenAIRE

Martz, Tyler Elizabeth

2015-01-01

Despite the availability of highly efficacious antiretroviral drug regimens for the prevention of mother-to-child HIV transmission (PMTCT), transmission rates remain higher than those achieved in clinical trials. Access to these efficacious drug regimens continues to expand rapidly in countries most affected by HIV. Such expansion is an important first step in dramatically reducing mother-to-child HIV transmission rates. However, beyond access to drug regimens, programs must also identify and...

Vertical transmission of Prunus necrotic ringspot virus: hitch-hiking from gametes to seedling.

Science.gov (United States)

Amari, Khalid; Burgos, Lorenzo; Pallás, Vicente; Sánchez-Pina, Maria Amelia

2009-07-01

The aim of this work was to follow Prunus necrotic ringspot virus (PNRSV) infection in apricot reproductive tissues and transmission of the virus to the next generation. For this, an analysis of viral distribution in apricot reproductive organs was carried out at different developmental stages. PNRSV was detected in reproductive tissues during gametogenesis. The virus was always present in the nucellus and, in some cases, in the embryo sac. Studies within infected seeds at the embryo globular stage revealed that PNRSV infects all parts of the seed, including embryo, endosperm and testa. In the torpedo and bent cotyledon developmental stages, high concentrations of the virus were detected in the testa and endosperm. At seed maturity, PNRSV accumulated slightly more in the embryo than in the cotyledons. In situ hybridization showed the presence of PNRSV RNA in embryos obtained following hand-pollination of virus-free pistils with infected pollen. Interestingly, tissue-printing from fruits obtained from these pistils showed viral RNA in the periphery of the fruits, whereas crosses between infected pistils and infected pollen resulted in a total invasion of the fruits. Taken together, these results shed light on the vertical transmission of PNRSV from gametes to seedlings.

Status of nosocomial tuberculosis transmission prevention in hospitals in Thailand.

Science.gov (United States)

Unahalekhaka, Akeau; Lueang-a-papong, Suchada; Chitreecheur, Jittaporn

2014-03-01

A national survey was conducted during July to September 2009 to determine tuberculosis (TB) prevention activities, problems, and support needed of Thai hospitals. Ninety-seven percent of hospitals established TB isolation policy, 96.3% provided guidelines for caring of TB patients, 95% and 91.8% provided prevention of TB transmission and environmental management guideline, and 92.6% established screening system for TB in the outpatient department (OPD). A half of hospitals had problems with isolation rooms and difficulties in screening TB cases in the OPD. Support needed included consultation on structure and ventilation systems, personnel training, national TB prevention, and TB screening guideline. Strengthening TB prevention activities, providing expert consultation, and national guidelines may help hospitals improve their TB prevention activities. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Korean clinical practice guidelines for preventing the transmission of infections in hemodialysis facilities

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Hayne Cho Park

2018-03-01

Full Text Available Patients receiving hemodialysis are vulnerable to infectious diseases due to their impaired immunity and high risk of exposure to pathogens. To protect patients, staff, and visitors from potential infections, each hemodialysis unit should establish and follow standard infection control and prevention measures. Therefore, clinical practice guidelines were developed by a working group of nephrologists and infection control specialists to provide evidence-based guidance for dialysis physicians and nurses, with the aim of preventing infection transmission and controlling infection sources in hemodialysis facilities. The areas of infection control covered by these guidelines include standard precautions, isolation strategies, vascular access, water treatment, cleaning/disinfecting/sterilizing, and vaccination. This special report summarizes the key recommendations from the Korean clinical practice guidelines for preventing the transmission of infections in hemodialysis facilities.

Effectiveness of condoms in preventing HIV transmission.

Science.gov (United States)

Pinkerton, S D; Abramson, P R

1997-05-01

The consistent use of latex condoms continues to be advocated for primary prevention of HIV infection despite limited quantitative evidence regarding the effectiveness of condoms in blocking the sexual transmission of HIV. Although recent meta-analyses of condom effectiveness suggest that condoms are 60 to 70% effective when used for HIV prophylaxis, these studies do not isolate consistent condom use, and therefore provide only a lower bound on the true effectiveness of correct and consistent condom use. A reexamination of HIV seroconversion studies suggests that condoms are 90 to 95% effective when used consistently, i.e. consistent condom users are 10 to 20 times less likely to become infected when exposed to the virus than are inconsistent or non-users. Similar results are obtained utilizing model-based estimation techniques, which indicate that condoms decrease the per-contact probability of male-to-female transmission of HIV by about 95%. Though imperfect, condoms provide substantial protection against HIV infection. Condom promotion therefore remains an important international priority in the fight against AIDS.

Vertical transmission of Trypanosoma cruzi in the Province of Choapa, IV Region, Chile: Preliminary Report (2005-2008

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Werner Apt

2010-01-01

Full Text Available Congenital Chagas disease acquired special importance in Chile after the certification of the control of Triatoma infestans and transmission by blood donors affected with Trypanosoma cruzi. In order to establish adequate protocols for intervention and control in infected mother-neonate pairs in endemic zones of Chagas disease, we present partial results (2005-2008 of a pilot project which is being carried out in the Province of Choapa, IV Region, Chile, whose objectives are: determine the current prevalence of the disease in pregnant women, estimate the incidence of vertical transmission of T. cruzi to newborns, determine the lineages of the parasite present in mothers who do and do not transmit the disease, determine the prevalence of Chagas disease in maternal grandmothers of neonates and study placental histopathology. Preliminary results indicated that in this study period, 3.7% of the women who gave birth in the Province have Chagas disease and 2.5% of their newborns were infected. The most frequent T. cruzi genotypes found in mothers studied during pregnancy were TCI and TCIId, either alone or in mixed infections. A high percentage (74.3% of the grandmothers studied was infected with the parasite. In 29 placentas from mothers with Chagas disease we observed edema, necrosis, fibrinoid deposits and slight lymphoplasmocyte infiltration. In three placentas we found erythroblastosis and in one of them amastigote forms of T. cruzi; this was one of the cases of congenital infection. The evaluation of the diagnostic and control protocols generated will allow us to determine if it has been possible to modify the natural history of vertical transmission of T. cruzi in Chile.

Antiretroviral pre-exposure prophylaxis prevents vaginal transmission of HIV-1 in humanized BLT mice.

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Paul W Denton

2008-01-01

Full Text Available Worldwide, vaginal transmission now accounts for more than half of newly acquired HIV-1 infections. Despite the urgency to develop and implement novel approaches capable of preventing HIV transmission, this process has been hindered by the lack of adequate small animal models for preclinical efficacy and safety testing. Given the importance of this route of transmission, we investigated the susceptibility of humanized mice to intravaginal HIV-1 infection.We show that the female reproductive tract of humanized bone marrow-liver-thymus (BLT mice is reconstituted with human CD4+ T and other relevant human cells, rendering these humanized mice susceptible to intravaginal infection by HIV-1. Effects of HIV-1 infection include CD4+ T cell depletion in gut-associated lymphoid tissue (GALT that closely mimics what is observed in HIV-1-infected humans. We also show that pre-exposure prophylaxis with antiretroviral drugs is a highly effective method for preventing vaginal HIV-1 transmission. Whereas 88% (7/8 of BLT mice inoculated vaginally with HIV-1 became infected, none of the animals (0/5 given pre-exposure prophylaxis of emtricitabine (FTC/tenofovir disoproxil fumarate (TDF showed evidence of infection (Chi square = 7.5, df = 1, p = 0.006.The fact that humanized BLT mice are susceptible to intravaginal infection makes this system an excellent candidate for preclinical evaluation of both microbicides and pre-exposure prophylactic regimens. The utility of humanized mice to study intravaginal HIV-1 transmission is particularly highlighted by the demonstration that pre-exposure prophylaxis can prevent intravaginal HIV-1 transmission in the BLT mouse model.

Cost Analysis of an Intervention to Prevent Methicillin-Resistant Staphylococcus Aureus (MRSA Transmission.

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Michal Chowers

Full Text Available Our objective was to assess the cost implications of a vertical MRSA prevention program that led to a reduction in MRSA bacteremia.We performed a matched historical cohort study and cost analysis in a single hospital in Israel for the years 2005-2011. The cost of MRSA bacteremia was calculated as total hospital cost for patients admitted with bacteremia and for patients with hospital-acquired bacteremia, the difference in cost compared to matched controls. The cost of prevention was calculated as the sum of the cost of microbiology tests, single-use equipment used for patients in isolation, and infection control personnel.An average of 20,000 patients were screened yearly. The cost of prevention was $208,100 per year, with the major contributor being laboratory cost. We calculated that our intervention averted 34 cases of bacteremia yearly: 17 presenting on admission and 17 acquired in the hospital. The average cost of a case admitted with bacteremia was $14,500, and the net cost attributable to nosocomial bacteremia was $9,400. Antibiotics contributed only 0.4% of the total disease management cost. When the annual cost of averted cases of bacteremia and that of prevention were compared, the intervention resulted in annual cost savings of $199,600.A vertical MRSA prevention program targeted at high-risk patients, which was highly effective in preventing bacteremia, is cost saving. These results suggest that allocating resources to targeted prevention efforts might be beneficial even in a single institution in a high incidence country.

Cost Analysis of an Intervention to Prevent Methicillin-Resistant Staphylococcus Aureus (MRSA) Transmission.

Science.gov (United States)

Chowers, Michal; Carmeli, Yehuda; Shitrit, Pnina; Elhayany, Asher; Geffen, Keren

2015-01-01

Our objective was to assess the cost implications of a vertical MRSA prevention program that led to a reduction in MRSA bacteremia. We performed a matched historical cohort study and cost analysis in a single hospital in Israel for the years 2005-2011. The cost of MRSA bacteremia was calculated as total hospital cost for patients admitted with bacteremia and for patients with hospital-acquired bacteremia, the difference in cost compared to matched controls. The cost of prevention was calculated as the sum of the cost of microbiology tests, single-use equipment used for patients in isolation, and infection control personnel. An average of 20,000 patients were screened yearly. The cost of prevention was $208,100 per year, with the major contributor being laboratory cost. We calculated that our intervention averted 34 cases of bacteremia yearly: 17 presenting on admission and 17 acquired in the hospital. The average cost of a case admitted with bacteremia was $14,500, and the net cost attributable to nosocomial bacteremia was $9,400. Antibiotics contributed only 0.4% of the total disease management cost. When the annual cost of averted cases of bacteremia and that of prevention were compared, the intervention resulted in annual cost savings of $199,600. A vertical MRSA prevention program targeted at high-risk patients, which was highly effective in preventing bacteremia, is cost saving. These results suggest that allocating resources to targeted prevention efforts might be beneficial even in a single institution in a high incidence country.

What is the benefit of the biomedical and behavioral interventions in preventing HIV transmission?

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Ricardo Kuchenbecker

2015-09-01

Full Text Available ABSTRACTIntroduction:Scientific evidence supports the sinergy between biomedical and behavioral interventions aimed at preventing the transmission of HIV as a strategy to eradicate AIDS.Objective:To characterize comparatively the benefits from biomedical and behavioral interventions to prevent HIV transmission.Methods:Narrative review. We performed a comparative analysis of the benefits of studied interventions by means of estimating the number needed to treat (NNT. Evaluated interventions: counseling activities for behavior change to prevent exposure to HIV; antiretroviral pre-exposure prophylaxis (PrEP and antiretroviral post-exposure prophylasis (PEP for HIV and treatment of serodiscordant couples as a strategy for prevention of HIV transmission (TasP.Results:counseling interventions and TasP have smaller NNTs, equal to, respectively, 11 (95%CI 9 - 18 at 12 months and 34 (95%CI 23 - 54 in 42 months comparatively to PrEP interventions, that resulted in 41 (95%CI 28 - 67 individuals receiving antiretrovirals in order to prevent one case of HIV infection at 36 months for men and serodiscordant couples. PEP interventions are associated with protective effects estimated at 81%. Lack of trials evaluating PEP prevents estimate of NNT.Conclusion:The estimate of the NNT can be a helpful parameter in the comparison between the effectiveness of different behavioral and biomedical HIV prevention strategies. Studies evaluating the benefit and safety of combined behavioral and biomedical interventions are needed, especially considering the attributable fraction of each component. Integration of behavioral and biomedical interventions is required to achieve complete suppression of the virus, and thus reducing viral replication, infectivity and the number of cases.

[Hemorrhagic dengue and vertical transmission to the newborn: a case report and literature review].

Science.gov (United States)

Morgan-Ortiz, Fred; Rodríguez-Lugo, Silvia Mirelle; León-Gil, María del Socorro; Gaxiola-Villa, Marisela; Martínez-Félix, Nora Selene; Lara-Avila, Leticia

2014-06-01

To describe the case of a patient with term pregnancy and infection with hemorrhagic dengue and vertical transmission to the newborn. Thirty-two year old patient with pregnancy at 38 weeks was admitted with fever 2 days earlier (38 degrees C). During her stay she continued with fever of 39 degrees C and platelets of 85,000/mm3. Serology for dengue NS1 antigen was reported positive. Labor was induced getting a new-born, male, 3,220 g, who breathed and cried at birth. During the postpartum period continued with fever, malaise, retro-ocular pain, generalized rash in upper and lower limbs, bleeding gums and petechial on the soft palate and thrombocytopenia of 5,000/mm3, later. At 8 days of stay, platelet concentration increased to 42,000/mm3 without requiring platelet concentrates and she was discharged after ten days in hospital with platelets of 94,000/mm3. The 4th day of extra-uterine live (EUL), neonate shows generalized rash over the trunk; The 5th day starts with 38 degrees C fever and thrombocytopenia (78,000/mm3). Dengue serological tests reported positive for Ag NS1 and negative for Abs IgM and IgG. Neonate was admitted to NICU, he continued with a decrease in platelet of 14,000/mm3- and ecchymotic areas by pressure and veno-punction sites. Four platelet concentrates were transfused. At 10th day of EUL platelet count was reported with 387,000/mm3. In an endemic area, such as Sinaloa state, in a pregnant woman with fever and thrombocytopenia, we should be alert to possibility of a DV infection and its complications. Although rare, such as this case, infection can be transmitted to fetus (vertical transmission) and produce a primary congenital dengue, even in its severe hemorrhagic types.

Vertical price transmission in the Danish food chain

DEFF Research Database (Denmark)

Jensen, Jørgen Dejgård; Møller, Anja Skadkær

2005-01-01

This purpose of this paper is to investigate price transmission patterns through selected Danish food chains – from primary production to processing, from processing to wholesale and from wholesale to retail prices. Specifically, the study addresses the following research questions: To what extent...... are commodity prices transmitted from one stage to another in the food chain? What is the time horizon in the price transmission? Is price transmission symmetric – in the short run and in the long run? Is the degree of price transmission affected by the degree of concentration in the supply and demand stage...... considered? These questions are analysed theoretically and empirically using econometric analysis. 6 food chains are investigated: pork, chicken, eggs, milk, sugar and apples. Preliminary empirical results suggest that for most commodities, price transmission tends to be upward asymmetric, i.e. stronger...

Prevention of mother-to-child HIV transmission cascade in China: a systematic review and meta-analysis.

Science.gov (United States)

Zeng, Huan; Chow, Eric P F; Zhao, Yong; Wang, Yang; Tang, Maozhi; Li, Leyu; Tang, Xue; Liu, Xi; Zhong, Yi; Wang, Ailing; Lo, Ying-Ru; Zhang, Lei

2016-03-01

The Chinese government has invested US$140 million annually on prevention of mother-to-child transmission (PMTCT) of HIV. This study evaluates the programme by examining the improvements in programme coverage HIV testing and provision of antiviral drugs along the PMTCT cascade. Data for PMTCT cascade indicators were collected through a comprehensive systematic review of published peer-reviewed English and Chinese literature during 2003-2011. Meta-analysis was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. This study included 113 publications. HIV prevalence among pregnant women in China who accessed antenatal care (ANC) remained below 0.1% during the past decade. HIV testing coverage in pregnant women attending ANC and in HIV-exposed infants at 18 months significantly increased from 62.4% (95% CI 4.7% to 98.2%) and 22.1% (16.3% to 32.3%) in 2003 to 90.3% (88.4% to 91.8%) and 82.8% (66.9% to 99.5%) in 2011 respectively, whereas antiretroviral (ARV) prophylaxis uptake increased from 35.2% (12.2% to 47.3%) and 26.9% (24.3% to 28.9%) to 86.2% (53.2% to 97.2%) and 90.3% (85.5% to 93.7%). HIV vertical transmission rate substantially decreased from 31.8% (25.7% to 38.6%) prior to the programme to 2.3% (1.4% to 3.8%) in 2011. During 2003-2011, among 25,312 (23,995-26,644) infants born to HIV-positive mothers who received ARV prophylaxis, 975 (564-1395) were diagnosed with HIV, corresponding to an average transmission rate of 3.9% (3.2% to 4.6%). However, while including transmissions among HIV-positive pregnant women who were lost along the cascade, the average transmission rate during 2003-2011 was 17.4% (15.8% to 19.0%). PMTCT programmes have reduced HIV mother-to-child transmission in China. Further improvements in the continuum of care remain essential in realising the full potential of the programme. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence

Interventions for preventing late postnatal mother-to-child transmission of HIV.

Science.gov (United States)

Horvath, Tara; Madi, Banyana C; Iuppa, Irene M; Kennedy, Gail E; Rutherford, George; Read, Jennifer S

2009-01-21

Worldwide, mother-to-child transmission (MTCT) of human immunodeficiency virus type 1 (HIV) represents the most common means by which children acquire HIV infection. Efficacious and effective interventions to prevent in utero and intrapartum transmission of HIV infection have been developed and implemented. However, a large proportion of MTCT of HIV occurs postnatally, through breast milk transmission. The objectives of this systematic review were to collate and assess the evidence regarding interventions to decrease late postnatal MTCT of HIV, and to determine the efficacy of such interventions in decreasing late postnatal MTCT of HIV, increasing overall survival, and increasing HIV-free survival. Electronic searches were undertaken using PubMed, EMBASE and other databases for 1980-2008. Hand searches of reference lists of pertinent reviews and studies, as well as abstracts from relevant conferences, were also conducted. Experts in the field were contacted to locate any other studies. The search strategy was iterative. Randomized clinical trials assessing the efficacy of interventions to prevent MTCT of HIV through breast milk were included in the analysis. Other trials and intervention cohort studies with relevant data also were included, but only when randomization was not feasible due to the nature of the intervention (i.e., infant feeding modality). Data regarding HIV infection status and vital status of infants born to HIV-infected women, according to intervention, were extracted from the reports of the studies. Six randomized clinical trials and one intervention cohort study were included in this review. Two trials addressed the issue of shortening the duration of (or eliminating) exposure to breast milk. In a trial of breastfeeding versus formula feeding, formula feeding was efficacious in preventing MTCT of HIV (the cumulative probability of HIV infection at 24 months was 36.7% in the breastfeeding arm and 20.5% in the formula arm [p = 0.001]), but the

A qualitative investigation into knowledge, beliefs, and practices surrounding mastitis in sub-Saharan Africa: what implications for vertical transmission of HIV?

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Hofmann Jennifer

2007-02-01

Full Text Available Abstract Background Mastitis constitutes an important risk factor in HIV vertical transmission. Very little, however, is known on how women in sub-Saharan Africa conceptualise health problems related to breastfeeding, such as mastitis, and how they act when sick. We aimed at filling this gap in knowledge, by documenting the indigenous nosography of mastitis, health seeking behaviour, and remedies for prophylaxis and treatment in rural sub-Saharan Africa. Methods The study was conducted in the Nouna Health District, rural Burkina Faso. We employed a combination of in-depth individual interviews and focus group discussions reaching both women and guérisseuers. All material was transcribed, translated, and analysed inductively, applying data and analyst triangulation. Results Respondents perceived breast problems related to lactation to be highly prevalent and described a sequence of symptoms which resembles the biomedical understanding of pathologies related to breastfeeding, ranging from breast engorgement (stasis to inflammation (mastitis and infection (breast abscess. The aetiology of disease, however, differed from biomedical notions as both women and guerisseurs distinguished between "natural" and "unnatural" causes of health problems related to breastfeeding. To prevent and treat such pathologies, women used a combination of traditional and biomedical therapies, depending on the perceived cause of illness. In general, however, a marked preference for traditional systems of care was observed. Conclusion Health problems related to breastfeeding are perceived to be very common in rural Burkina Faso. Further epidemiological research to assess the actual prevalence of such pathologies is urgently needed to inform the design of adequate control measures, especially given the impact of mastitis on HIV vertical transmission. Our investigation into local illness concepts and health care seeking behaviour is useful to ensure that such measures be

A Study on Knowledge, Attitude and Practice in Preventing Transmission of Scabies in Pesantren Darul Fatwa, Jatinangor

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Mahirah Binti Mohd Yusof

2015-03-01

Full Text Available Background: Scabies is caused by infestation and sensitization of Sarcoptess cabiei and is an endemic in tropical and subtropical regions around the world. Several factors in the disease transmission are overcrowded living conditions, poor personal hygiene, unhealthy behaviors and population density. Pesantren is a spesific name for an educational Islamic institution in Indonesia and which w could be one of the risk factors of the transmission the disease. Most of the students (santri are staying at the institution for a long time. The objective of this study was to know the level of knowledge, attitude and practice of santri in preventing scabies. Methods: A descriptive study was conducted on 45 santri in Pesantren Darul Fatwa in Jatinangor during September–December 2012. A questionnaire was set up consisting of questions about age, sex, basic knowledge, attitude, and practice of preventing the transmission of scabies. Data were analyzed using frequency distribution. Results: The level of knowledge and attitude of the respondents to prevent the transmission of scabies were good, meanwhile the level of practice was moderate. There were still questions that could not be answer by the respondents those were the etiology (31.1%, the cut off chain of transmission (40%, and how to prevent scabies (37.8%. Not washing the towel, changing the bed linen and pillow case every 2 weeks were the less good practice performed by the respondents. Conclusions: The knowledge and attitude towards the prevention of transmission of scabies are good while the practices are moderate. A further study with more sample size should be carried out including enviromental assessment.

Older Americans and AIDS: Transmission Risks and Primary Prevention Research Needs.

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Catania, Joseph A.; And Others

1989-01-01

Growing number of Acquired Immune Deficiency Syndrome (AIDS) cases among older Americans is of increasing concern. In context of primary prevention, reviews findings that bear on modes of human immunodeficiency virus (HIV) transmission (blood transfusions, sexual) among older individuals and knowledge of magnitude of the AIDS problem represented…

Ebselen alleviates testicular pathology in mice with Zika virus infection and prevents its sexual transmission.

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Yogy Simanjuntak

2018-02-01

Full Text Available Despite the low case fatality, Zika virus (ZIKV infection has been associated with microcephaly in infants and Guillain-Barré syndrome. Antiviral and vaccine developments against ZIKV are still ongoing; therefore, in the meantime, preventing the disease transmission is critical. Primarily transmitted by Aedes species mosquitoes, ZIKV also can be sexually transmitted. We used AG129 mice lacking interferon-α/β and -γ receptors to study the testicular pathogenesis and sexual transmission of ZIKV. Infection of ZIKV progressively damaged mouse testes, increased testicular oxidative stress as indicated by the levels of reactive oxygen species, nitric oxide, glutathione peroxidase 4, spermatogenesis-associated-18 homolog in sperm and pro-inflammatory cytokines including IL-1β, IL-6, and G-CSF. We then evaluated the potential role of the antioxidant ebselen (EBS in alleviating the testicular pathology with ZIKV infection. EBS treatment significantly reduced ZIKV-induced testicular oxidative stress, leucocyte infiltration and production of pro-inflammatory response. Furthermore, it improved testicular pathology and prevented the sexual transmission of ZIKV in a male-to-female mouse sperm transfer model. EBS is currently in clinical trials for various diseases. ZIKV infection could be on the list for potential use of EBS, for alleviating the testicular pathogenesis with ZIKV infection and preventing its sexual transmission.

Ebselen alleviates testicular pathology in mice with Zika virus infection and prevents its sexual transmission.

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Simanjuntak, Yogy; Liang, Jian-Jong; Chen, Si-Yu; Li, Jin-Kun; Lee, Yi-Ling; Wu, Han-Chung; Lin, Yi-Ling

2018-02-01

Despite the low case fatality, Zika virus (ZIKV) infection has been associated with microcephaly in infants and Guillain-Barré syndrome. Antiviral and vaccine developments against ZIKV are still ongoing; therefore, in the meantime, preventing the disease transmission is critical. Primarily transmitted by Aedes species mosquitoes, ZIKV also can be sexually transmitted. We used AG129 mice lacking interferon-α/β and -γ receptors to study the testicular pathogenesis and sexual transmission of ZIKV. Infection of ZIKV progressively damaged mouse testes, increased testicular oxidative stress as indicated by the levels of reactive oxygen species, nitric oxide, glutathione peroxidase 4, spermatogenesis-associated-18 homolog in sperm and pro-inflammatory cytokines including IL-1β, IL-6, and G-CSF. We then evaluated the potential role of the antioxidant ebselen (EBS) in alleviating the testicular pathology with ZIKV infection. EBS treatment significantly reduced ZIKV-induced testicular oxidative stress, leucocyte infiltration and production of pro-inflammatory response. Furthermore, it improved testicular pathology and prevented the sexual transmission of ZIKV in a male-to-female mouse sperm transfer model. EBS is currently in clinical trials for various diseases. ZIKV infection could be on the list for potential use of EBS, for alleviating the testicular pathogenesis with ZIKV infection and preventing its sexual transmission.

Effectiveness of semen washing to prevent HIV transmission and assist pregnancy in HIV-discordant couples: a systematic review and meta-analysis

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Zafer, Maryam; Horvath, Hacsi; Mmeje, Okeoma; van der Poel, Sheryl; Semprini, Augusto; Rutherford, George; Brown, Joelle

2015-01-01

Objective To evaluate the effectiveness of semen washing in HIV-discordant couples in which the male partner is infected Design Systematic review and meta-analysis Setting All countries Patient(s) Forty single-arm, open label studies among HIV-discordant couples that underwent intrauterine insemination (IUI) or in vitro fertilization (IVF) with or without intracytoplasmic sperm injection (ICSI) using washed semen Intervention(s) Semen washing followed by IUI, IVF, or IVF/ICSI Main outcome measure(s) Primary outcome: HIV transmission to HIV-uninfected women; secondary outcomes: HIV transmission to newborns and proportion of couples achieving a clinical pregnancy Result(s) No HIV transmission occurred in 11,585 cycles of assisted reproduction using washed semen among 3,994 women (95% confidence interval [CI] = 0–0.0001). Among the subset of HIV-infected men without plasma viral suppression at the time of semen washing, no HIV seroconversions occurred among 1,023 women following 2,863 cycles of assisted reproduction using washed semen (95%CI= 0–0.0006). Studies that measured HIV transmission to infants reported no cases of vertical transmission (0/1,026, 95% CI= 0–0.0029). Overall, 56.3% (2,357/4,184, 95%CI=54.8%–57.8%) of couples achieved a clinical pregnancy using washed semen. Conclusion(s) Semen washing appears to significantly reduce the risk of transmission in HIV-discordant couples desiring children, regardless of viral suppression in the male partner. There are no randomized, controlled studies or studies from low-income countries, especially those with a large burden of HIV. Continued development of lower-cost semen washing and assisted reproduction technologies is needed. Integration of semen washing into HIV prevention interventions could help further reduce the spread of HIV. PMID:26688556

Neglected Non-Traditional Routes of Hepatitis B Virus Transmission

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Ling Wang

2016-11-01

Full Text Available According to Chinese Guideline of Prevention and Treatment for Chronic Hepatitis B which is published in October, 2015, hepatitis B virus (HBV is mainly transmitted via injection, vertical transmission, and sexual contact, furthermore, invasive procedures including pedicure and tattooing as well as sharing shavers and toothbrushes are also regarded as risk factors. These traditional HBV transmission pathways are in accordance with the corresponding WHO guideline. However, some of the statements in the guidelines such as close contact with active HBV carriers like sharing hygiene facilities and dining together as well as bites by blood-sucking arthropod like mosquito do not transmit HBV need to be questioned because related previous studies did not support these statements.

HLA-G and vertical mother-to-child transmission of human papillomavirus infection.

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Louvanto, Karolina; Roger, Michel; Faucher, Marie-Claude; Syrjänen, Kari; Grenman, Seija; Syrjänen, Stina

2018-06-01

Role of host factors in transmission of human papillomavirus (HPV)-infection from mother to her offspring is not known. Our aim was to study whether human leukocyte antigen (HLA)-G allele concordance among the mother-child pairs could facilitate vertical transmission of HPV, because HLA-G may contribute to immune tolerance in pregnancy. Altogether, 310 mother-child pairs were included from the Finnish Family HPV study. Overall, nine different HLA-G alleles were identified. The HLA-G genotype concordance of G ∗ 01:01:01/01:04:01 increased the risk of high risk (HR)-HPV genotype positivity in cord blood and infant's oral mucosa. The mother-child concordance of G ∗ 01:01:02/01:01:02 increased the risk of oral HPV positivity with HR-HPV genotypes both in the mother and offspring; OR 2.45 (95%CI 1.24-4.85). Discordant HLA-G allele for G ∗ 01:04:01 and for G ∗ 01:06 was significantly associated with infant's oral low risk (LR)-HPV at birth, OR 3.07 (95%CI 1.01-9.36) and OR 5.19 (95%CI 1.22-22.03), respectively. HLA-G had no association with HPV genotype-specific concordance between the mother and child at birth nor influence on perinatal HPV status of the child. Taken together, our results show that HLA-G molecules have a role in predicting the newborn's likelihood for oral HPV infection at birth. Copyright © 2018 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Measurement of the wetting profile in concrete samples with vertical water by gamma radiation transmission method

International Nuclear Information System (INIS)

Silva, L.M. da; Rocha, M.C. da; Appoloni, C.R.; Portezan Filho, O.; Lopes, F.; Melquiades, F.L.; Santos, E.A. dos; Santos, A.O. dos; Moreira, A.C.; Poetker, W.E.; Almeida, E. de; Tannous, C.Q.; Kuramoto, R.; Cavalcante, F.H. de M.; Barbieri, P.F.

2000-01-01

Samples of concrete for popular habitation (0,1x0,03x0,1 m) and cellular concrete (0,1x0,05x0,1 m) were submitted to water vertical ascending infiltration. The moisture content spatial and temporal evolution of each sample it was monitored in three halfway positions in a same horizontal line, applying the gamma rays transmission method. The data were taken with a 137 Cs (3,7x10 10 Bq, 0662 MeV) source, NaI (Tl) of 2x2' detector coupled to between wetting profiles and concrete strength. The cellular concrete showed a wetting profile compatible to its greater porosity. (author)

Fatores que influenciam a transmissão vertical do vírus da imunodeficiência humana tipo 1 Risk factors for vertical transmission of the human immunodeficiency virus type 1

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Geraldo Duarte

2005-11-01

Full Text Available Um dos mais expressivos avanços visando controlar a dispersão da infecção pelo vírus da imunodeficiência humana tipo 1 (HIV-1 ocorreu no contexto da transmissão vertical (TV, reduzindo-a de cifras que chegavam a 40% para menos de 3%. O progresso tecnológico, aliado ao melhor conhecimento fisiopatológico dessa infecção, permitiu elencar as situações e os fatores que elevam as taxas de transmissão perinatal desse vírus, indicando quais as intervenções mais adequadas para o seu controle. Estas situações de maior risco para a TV do HIV-1 podem ser agrupadas em fatores maternos, anexiais, obstétricos, fetais, virais e pós-natais. Dos fatores maternos destaca-se a carga viral, o principal indicador do risco desta forma de transmissão. No entanto, a despeito da relevância da carga viral, ela não é a única variável desta equação, devendo ser lembrado o uso de drogas ilícitas, parceria sexual múltipla com sexo desprotegido, desnutrição, tabagismo, doença materna avançada e falta de adesão ou de acesso aos anti-retrovirais. Dos fatores anexiais apontam-se a corioamniorrexe prolongada, a perda da integridade placentária e a expressão dos receptores secundários no tecido placentário. Entre os fatores obstétricos deve ser lembrado que intervenções invasivas sobre o feto ou câmara amniótica, cardiotocografia interna, tipo de parto e contato do feto/recém-nascido com sangue materno também são importantes elementos a serem controlados. Dos fatores fetais são citados a expressão de receptores secundários para o HIV-1, a suscetibilidade genética, a função reduzida dos linfócitos T-citotóxicos e a prematuridade. Sobre os fatores virais aventa-se que a presença de mutações e cepas indutoras de sincício sejam fatores de risco para a TV. Finalmente, há os fatores pós-natais, representados pela carga viral elevada no leite, baixa concentração de anticorpos neste fluído, mastite clínica e les

Estratégias que reduzem a transmissão vertical do vírus da imunodeficiência humana tipo 1 Strategies to avoid vertical transmission of human immunodeficiency virus type 1

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Geraldo Duarte

2005-12-01

Full Text Available O conhecimento dos fatores ou situações que influenciam a transmissão vertical (TV do vírus da imunodeficiência humana tipo 1 (HIV-1 levou à adoção de estratégias com redução de taxas ao longo dos anos: de 40% para menos de 3% na atualidade. Um dos maiores avanços foi o uso profilático da zidovudina (AZT, administrada durante o pré-natal (via oral, no período anteparto (via endovenosa e ao recém-nascido (via oral. Esta intervenção reduz a TV do HIV-1 em 68%, fazendo com que seja considerada a estratégia isolada de maior efetividade. Na seqüência cronológica dos avanços, observou-se que a carga viral elevada é o principal indicador do risco para esta forma de transmissão. Como o AZT não reduz a carga viral e não consegue controlar a taxa residual observada na TV do HIV-1, a utilização dos esquemas profiláticos utilizando três anti-retrovirais foi objetivamente impulsionada. Completando o ciclo das estratégias obstétricas de maior impacto na redução da TV do HIV-1 está a cesárea eletiva, cuja efetividade está ligada à observação dos critérios de sua indicação: carga viral aferida após a 34ª semana de gravidez apresentando contagem maior que 1000 cópias/ml, gestação com mais de 38 semanas confirmada por ultra-sonografia, membranas corioamnióticas íntegras e fora de trabalho de parto. Nos casos em que a via de parto tem indicação obstétrica, deve ser lembrado que a corioamniorrexe prolongada, manobras invasivas sobre o feto, parto instrumentalizado e a episiotomia são situações que devem ser evitadas. Das intervenções pós-natais consideradas importantes para a redução da TV do HIV-1 são apontadas a recepção pediátrica (deve ser efetivada por profissional treinado evitando microtraumatismos de mucosa nas manobras aspirativas, utilização do AZT neonatal (por período de seis semanas e a amamentação artificial. Especial atenção deve ser dispensada às orientações para as nutrizes

Lack of protection against vertical transmission of HIV-1 by interferons produced during pregnancy in a cohort from East African republic of Malawi

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Zachar, V.; Fazio-Tirrozzo, G.; Fink, T.; Roberts, D. J.; Broadhead, R. L.; Brabin, B.; Ebbesen, P.

2000-01-01

Interferons (IFNs) associated with pregnancy were studied for their possible role in inhibition of vertical transmission of the human immunodeficiency virus type 1 (HIV-1). A study group was composed of 43 HIV-1-positive mothers, of whom 15 transmitted the virus to the offspring and 28 did not. The

Modeling social transmission dynamics of unhealthy behaviors for evaluating prevention and treatment interventions on childhood obesity.

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Frerichs, Leah M; Araz, Ozgur M; Huang, Terry T-K

2013-01-01

Research evidence indicates that obesity has spread through social networks, but lever points for interventions based on overlapping networks are not well studied. The objective of our research was to construct and parameterize a system dynamics model of the social transmission of behaviors through adult and youth influence in order to explore hypotheses and identify plausible lever points for future childhood obesity intervention research. Our objectives were: (1) to assess the sensitivity of childhood overweight and obesity prevalence to peer and adult social transmission rates, and (2) to test the effect of combinations of prevention and treatment interventions on the prevalence of childhood overweight and obesity. To address the first objective, we conducted two-way sensitivity analyses of adult-to-child and child-to-child social transmission in relation to childhood overweight and obesity prevalence. For the second objective, alternative combinations of prevention and treatment interventions were tested by varying model parameters of social transmission and weight loss behavior rates. Our results indicated child overweight and obesity prevalence might be slightly more sensitive to the same relative change in the adult-to-child compared to the child-to-child social transmission rate. In our simulations, alternatives with treatment alone, compared to prevention alone, reduced the prevalence of childhood overweight and obesity more after 10 years (1.2-1.8% and 0.2-1.0% greater reduction when targeted at children and adults respectively). Also, as the impact of adult interventions on children was increased, the rank of six alternatives that included adults became better (i.e., resulting in lower 10 year childhood overweight and obesity prevalence) than alternatives that only involved children. The findings imply that social transmission dynamics should be considered when designing both prevention and treatment intervention approaches. Finally, targeting adults may

Modeling social transmission dynamics of unhealthy behaviors for evaluating prevention and treatment interventions on childhood obesity.

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Leah M Frerichs

Full Text Available Research evidence indicates that obesity has spread through social networks, but lever points for interventions based on overlapping networks are not well studied. The objective of our research was to construct and parameterize a system dynamics model of the social transmission of behaviors through adult and youth influence in order to explore hypotheses and identify plausible lever points for future childhood obesity intervention research. Our objectives were: (1 to assess the sensitivity of childhood overweight and obesity prevalence to peer and adult social transmission rates, and (2 to test the effect of combinations of prevention and treatment interventions on the prevalence of childhood overweight and obesity. To address the first objective, we conducted two-way sensitivity analyses of adult-to-child and child-to-child social transmission in relation to childhood overweight and obesity prevalence. For the second objective, alternative combinations of prevention and treatment interventions were tested by varying model parameters of social transmission and weight loss behavior rates. Our results indicated child overweight and obesity prevalence might be slightly more sensitive to the same relative change in the adult-to-child compared to the child-to-child social transmission rate. In our simulations, alternatives with treatment alone, compared to prevention alone, reduced the prevalence of childhood overweight and obesity more after 10 years (1.2-1.8% and 0.2-1.0% greater reduction when targeted at children and adults respectively. Also, as the impact of adult interventions on children was increased, the rank of six alternatives that included adults became better (i.e., resulting in lower 10 year childhood overweight and obesity prevalence than alternatives that only involved children. The findings imply that social transmission dynamics should be considered when designing both prevention and treatment intervention approaches. Finally

Effectiveness of semen washing to prevent human immunodeficiency virus (HIV) transmission and assist pregnancy in HIV-discordant couples: a systematic review and meta-analysis.

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Zafer, Maryam; Horvath, Hacsi; Mmeje, Okeoma; van der Poel, Sheryl; Semprini, Augusto E; Rutherford, George; Brown, Joelle

2016-03-01

To evaluate the effectiveness of semen washing in human immunodeficiency virus (HIV)-discordant couples in which the male partner is infected. Systematic review and meta-analysis. Not applicable. Forty single-arm open-label studies among HIV-discordant couples that underwent intrauterine insemination (IUI) or in vitro fertilization (IVF) with or without intracytoplasmic sperm injection (ICSI) using washed semen. Semen washing followed by IUI, IVF, or IVF/ICSI. HIV transmission to HIV-uninfected women; secondary outcomes: HIV transmission to newborns and proportion of couples achieving a clinical pregnancy. No HIV transmission occurred in 11,585 cycles of assisted reproduction with the use of washed semen among 3,994 women. Among the subset of HIV-infected men without plasma viral suppression at the time of semen washing, no HIV seroconversions occurred among 1,023 women after 2,863 cycles of assisted reproduction with the use of washed semen. Studies that measured HIV transmission to infants reported no cases of vertical transmission. Overall, 56.3% of couples (2,357/4,184) achieved a clinical pregnancy with the use of washed semen. Semen washing appears to significantly reduce the risk of transmission in HIV-discordant couples desiring children, regardless of viral suppression in the male partner. There are no randomized controlled studies or studies from low-income countries, especially those with a large burden of HIV. Continued development of lower-cost semen washing and assisted reproduction technologies is needed. Integration of semen washing into HIV prevention interventions could help to further reduce the spread of HIV. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Prevention of mother to child HIV transmission Prevención de la transmisión perinatal de HIV

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Adriana S. Duran

2006-02-01

Full Text Available We describe the impact of strategies to reduce HIV-1 vertical transmission on a cohort of pregnant women and evaluate toxicity related to antiretroviral (ARV therapy and prevalence of birth defects. In this observational, retrospective, longitudinal and descriptive study, we have reviewed the data base and clinical charts from a cohort of 351 pregnant women with HIV infection admitted to a public hospital in Buenos Aires from April 1994 to August 2003. Eighty percent of women were infected by sexual transmission. Diagnosis of HIV infection was performed before pregnancy in 38.5% of cases; 241 patients received some kind of ARV therapy, combined therapy was administered in 123 of cases. The overall transmission rate was 9.6%, and antiretroviral therapy was the most significant factor associated with the transmission rate. HIV transmission odds were 0.04 for any ARV treatment versus no therapy. No cases of HIV transmission were observed among women given combination ARV therapy. More prevalent secondary effects associated to ARV therapy were anemia, hypercholesterolemia, increase of ALP and hypertrigliceridemia. In conclusion, antiretroviral therapy, particularly combined ARV therapy, irrespective of type of delivery, was associated with a reduced risk of HIV transmission without an increase in toxicity or incidence of congenital abnormalities in the short-term.En este estudio se describe el impacto de las estrategias implementadas para reducir la trasmisión vertical de HIV en una cohorte de mujeres embarazadas. Se evaluó, también, la toxicidad relacionada a la terapia antirretroviral y la prevalencia de malformaciones congénitas. Se revisaron, retrospectivamente, las historias clínicas y la base de datos de 351 mujeres embarazadas, con infección por HIV, admitidas en un hospital público de la Ciudad de Buenos Aires, entre abril de 1994 y agosto de 2003. Se obtuvieron datos completos de 351 pacientes. El 80% de las mujeres adquirieron la

Computational modeling of interventions and protective thresholds to prevent disease transmission in deploying populations.

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Burgess, Colleen; Peace, Angela; Everett, Rebecca; Allegri, Buena; Garman, Patrick

2014-01-01

Military personnel are deployed abroad for missions ranging from humanitarian relief efforts to combat actions; delay or interruption in these activities due to disease transmission can cause operational disruptions, significant economic loss, and stressed or exceeded military medical resources. Deployed troops function in environments favorable to the rapid and efficient transmission of many viruses particularly when levels of protection are suboptimal. When immunity among deployed military populations is low, the risk of vaccine-preventable disease outbreaks increases, impacting troop readiness and achievement of mission objectives. However, targeted vaccination and the optimization of preexisting immunity among deployed populations can decrease the threat of outbreaks among deployed troops. Here we describe methods for the computational modeling of disease transmission to explore how preexisting immunity compares with vaccination at the time of deployment as a means of preventing outbreaks and protecting troops and mission objectives during extended military deployment actions. These methods are illustrated with five modeling case studies for separate diseases common in many parts of the world, to show different approaches required in varying epidemiological settings.

Computational Modeling of Interventions and Protective Thresholds to Prevent Disease Transmission in Deploying Populations

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Colleen Burgess

2014-01-01

Full Text Available Military personnel are deployed abroad for missions ranging from humanitarian relief efforts to combat actions; delay or interruption in these activities due to disease transmission can cause operational disruptions, significant economic loss, and stressed or exceeded military medical resources. Deployed troops function in environments favorable to the rapid and efficient transmission of many viruses particularly when levels of protection are suboptimal. When immunity among deployed military populations is low, the risk of vaccine-preventable disease outbreaks increases, impacting troop readiness and achievement of mission objectives. However, targeted vaccination and the optimization of preexisting immunity among deployed populations can decrease the threat of outbreaks among deployed troops. Here we describe methods for the computational modeling of disease transmission to explore how preexisting immunity compares with vaccination at the time of deployment as a means of preventing outbreaks and protecting troops and mission objectives during extended military deployment actions. These methods are illustrated with five modeling case studies for separate diseases common in many parts of the world, to show different approaches required in varying epidemiological settings.

Current Perspectives on Prevention of Mother-to-Child Transmission of Syphilis

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2016-01-01

This article aims to provide an update on the prevention of mother-to-child transmission of syphilis by drawing upon some important basic concepts and reviewing the most recent literature on the diagnosis and treatment of syphilis in pregnancy. New technologies, such as automated and point-of-care immunologic tests, are shifting some paradigms, which will certainly be further investigated in the forthcoming years. This is the time to carefully evaluate traditional as well as new strategies to prevent congenital syphilis. Adverse outcomes of mother-to-child transmission of syphilis can be prevented with antenatal screening and penicillin therapy, which proved to have an excellent cost-benefit ratio even in populations with a low prevalence of syphilis. However, syphilis epidemiology is influenced by socioeconomic and cultural factors, and major challenges are faced by poor and developing countries in which the severity of the problem is extremely alarming. On the other hand, the emergence of new technologies has raised doubts about the best algorithm to be used when proper laboratory resources are available. Conditions are quite heterogeneous across populations, and some procedures should not be generalized while there is no evidence that supports some changes and while in-depth studies about local conditions are not conducted. Official organizations need to be alert in order to avoid isolated decisions and ensure that evidence-based guidelines be used in the management of syphilis in pregnancy. PMID:27081586

Comparative cost-effectiveness of Option B+ for prevention of mother to child transmission of HIV in Malawi: Mathematical modelling study

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Tweya, Hannock; Keiser, Olivia; Haas, Andreas D.; Tenthani, Lyson; Phiri, Sam; Egger, Matthias; Estill, Janne

2016-01-01

Objective To estimate the cost-effectiveness of prevention of mother to child transmission (MTCT) of HIV with lifelong antiretroviral therapy (ART) for pregnant and breastfeeding women (‘Option B+’) compared to ART during pregnancy or breastfeeding only unless clinically indicated (‘Option B’). Design Mathematical modelling study of first and second pregnancy, informed by data from the Malawi Option B+ programme. Methods Individual-based simulation model. We simulated cohorts of 10,000 women and their infants during two subsequent pregnancies, including the breastfeeding period, with either Option B+ or B. We parameterised the model with data from the literature and by analysing programmatic data. We compared total costs of ante-natal and post-natal care, and lifetime costs and disability-adjusted life-years (DALYs) of the infected infants between Option B+ and Option B. Results During the first pregnancy, 15% of the infants born to HIV-infected mothers acquired the infection. With Option B+, 39% of the women were on ART at the beginning of the second pregnancy, compared to 18% with Option B. For second pregnancies, the rates MTCT were 11.3% with Option B+ and 12.3% with Option B. The incremental cost-effectiveness ratio comparing the two options ranged between about US$ 500 and US$ 1300 per DALY averted. Conclusion Option B+ prevents more vertical transmissions of HIV than Option B, mainly because more women are already on ART at the beginning of the next pregnancy. Option B+ is a cost-effective strategy for PMTCT if the total future costs and lost lifetime of the infected infants are taken into account. PMID:26691682

Prevalence of toxoplasmosis in pregnant women and vertical transmission of Toxoplasma gondii in patients from basic units of health from Gurupi, Tocantins, Brazil, from 2012 to 2014.

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Gontijo da Silva, Marcos; Clare Vinaud, Marina; de Castro, Ana Maria

2015-01-01

Toxoplasmosis is a parasitary disease that presents high rates of gestational and congenital infection worldwide being therefore considered a public health problem and a neglected disease. To determine the prevalence of toxoplasmosis amongst pregnant women and vertical transmission of Toxoplasma gondii in their newborns attended in the Basic Units of Health (BUH) from the city of Gurupi, state of Tocantins, Brazil. A prevalence study was performed, including 487 pregnant women and their newborns attended in the BUH of the urban zone of the city of Gurupi, state of Tocantins, Brazil, during the period from February 2012 to February 2014. The selection of the pregnant women occurred by convenience. In the antenatal admission they were invited to participate in this study. Three samples of peripheral blood were collected for the detection of specific anti-T. gondii IgG, IgM and IgA through ELISA, for the polimerase chain reaction (PCR) and IgG avidity during pregnancy. When IgM antibodies were detected the fetal and newborn infection investigation took place. The newborn was investigated right after birth and after one year of age through serology and PCR to confirm/exclude the vertical transmission. The analyses were performed in the Studies of the Host-Parasite Relationship Laboratory (LAERPH, IPTSP-UFG), Goiania, state of Goias, Brazil. The results were inserted in a data bank in Epi-Info 3.3.2 statistic software in which the analysis was performed with p≤5%. The toxoplasmosis infection was detected in 68.37% (333/487, CI95%: 64.62-72.86). The toxoplasmosis chronic infection prevalence was of 63.03% (307/487, CI95%: 58.74-67.32). The prevalence of maternal acute infection was of 5.33% (26/487; CI95%: 3.3-7.3) suspected by IgM antibodies detection in the peripheral blood. The prevalence of confirmed vertical transmission was of 28% (7/25; CI95%: 10.4-45.6). These results show an elevated prevalence of toxoplasmosis in pregnant women and vertical transmission of T

Experimental toxoplasmosis in Balb/c mice. Prevention of vertical disease transmission by treatment and reproductive failure in chronic infection

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B Fux

2000-01-01

Full Text Available In a study of congenital transmission during acute infection of Toxoplasma gondii, 23 pregnant Balb/c mice were inoculated orally with two cysts each of the P strain. Eight mice were inoculated 6-11 days after becoming pregnant (Group 1. Eight mice inoculated on the 10th-15th day of pregnancy (Group 2 were treated with 100 mg/kg/day of minocycline 48 h after inoculation. Seven mice inoculated on the 10th-15th day of pregnancy were not treated and served as a control (Group 3. Congenital transmission was evaluated through direct examination of the brains of the pups or by bioassay and serologic tests. Congenital transmission was observed in 20 (60.6% of the 33 pups of Group 1, in one (3.6% of the 28 pups of Group 2, and in 13 (54.2% of the 24 pups of Group 3. Forty-nine Balb/c mice were examined in the study of congenital transmission of T. gondii during chronic infection. The females showed reproductive problems during this phase of infection. It was observed accentuated hypertrophy of the endometrium and myometrium. Only two of the females gave birth. Our results demonstrate that Balb/c mice with acute toxoplasmosis can be used as a model for studies of congenital T. gondii infection. Our observations indicate the potential of this model for testing new chemotherapeutic agents against congenital toxoplasmosis.

The role of adaptations in two-strain competition for sylvatic Trypanosoma cruzi transmission.

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Kribs-Zaleta, Christopher M; Mubayi, Anuj

2012-01-01

This study presents a continuous-time model for the sylvatic transmission dynamics of two strains of Trypanosoma cruzi enzootic in North America, in order to study the role that adaptations of each strain to distinct modes of transmission (classical stercorarian transmission on the one hand, and vertical and oral transmission on the other) may play in the competition between the two strains. A deterministic model incorporating contact process saturation predicts competitive exclusion, and reproductive numbers for the infection provide a framework for evaluating the competition in terms of adaptive trade-off between distinct transmission modes. Results highlight the importance of oral transmission in mediating the competition between horizontal (stercorarian) and vertical transmission; its presence as a competing contact process advantages vertical transmission even without adaptation to oral transmission, but such adaptation appears necessary to explain the persistence of (vertically-adapted) T. cruzi IV in raccoons and woodrats in the southeastern United States.

Insights into the mechanisms of vertical transmission of HIV-1. BIOMED2 Working Group on the in utero transmission of HIV-1.

Science.gov (United States)

Menu, E; Mognetti, B; Moussa, M; Nardese, V; Tresoldi, L; Tscherning, C; Mbopi Keou, F X; Dubanchet, S; Mauclere, P; Fenyö, E M; Scarlatti, G; Barre-Sinoussi, F; Chaouat, G

1997-12-01

This paper is a summary of three oral presentations, as well as the ensuing discussion, at the Rijeka/Opatija 3rd Alps Adria Immunology meeting by three members of the European Biomed group on vertical transmission of HIV (G. Chaouat, F. Barre-Sinoussi, G. Scarlatti). This group also involves the laboratories of D. Dormont (CEA, Fontenay aux roses, France), P. Gounon (Electron Microscopy, the Pasteur Institute, France; Irène Athanassakis, University of Crete, Greece; Eva Maria Fenyö, Karolinska Institute, Sweden; and Larry Guilbert, Canada). As such, this paper intends to be neither a review, nor an original article, but rather is an opinion paper discussing the working hypothesis of this network, as well as some of their recent results, which were presented at this meeting. The paper was issued at the request of the organizers of the meeting.

Vertical transmission of avian leukosis virus subgroup J (ALV-J) from hens infected through artificial insemination with ALV-J infected semen.

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Li, Yang; Cui, Shuai; Li, Weihua; Wang, Yixin; Cui, Zhizhong; Zhao, Peng; Chang, Shuang

2017-06-29

Avian leukosis virus (ALV) is one of the main causes of tumour development within the poultry industry in China. The subgroup J avian leukosis viruses (ALV-J), which induce erythroblastosis and myelocytomatosis, have the greatest pathogenicity and transmission ability within this class of viruses. ALV can be transmitted both horizontally and vertically; however, the effects of ALV infection in chickens-especially roosters-during the propagation, on future generations is not clear. Knowing the role of the cock in the transmission of ALV from generation to generation might contribute to the eradication programs for ALV. The results showed that two hens inseminated with ALV-J-positive semen developed temporary antibody responses to ALV-J at 4-5 weeks post insemination. The p27 antigen was detected in cloacal swabs of six hens, and in 3 of 26 egg albumens at 1-6 weeks after insemination. Moreover, no viremia was detected at 6 weeks after insemination even when virus isolation had been conducted six times at weekly intervals for each of the 12 females. However, ALV-J was isolated from 1 of their 34 progeny chicks at 1 week of age, and its gp85 had 98.4%-99.2% sequence identity with the gp85 of ALV-J isolated from semen samples of the six cocks. Our findings indicated that females that were late horizontally infected with ALV-J by artificial insemination might transmit the virus to progeny through eggs, which amounts to vertical transmission.

Screening of Pregnant Women for Anti-Toxoplasma Antibodies and their Newborn for Vertical Transmission

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Aysha Yasmeen

2017-10-01

Full Text Available Introduction: Toxoplasmosis is a world-wide protozoan-zoonosis caused by Toxoplasma gondii (T. gondii. Primary infections during pregnancy may result in miscarriages, still births, and congenital malformations in the new born. Studies on vertical transmission of toxoplasmosis from India are lacking. Aim: To estimate the seroprevalence of antibodies to T. gondii among pregnant women from the rural population of Kolar and to document vertical transmissions, if any. Materials and Methods: Anti-Toxoplasma IgG levels were estimated among 251 women admitted for labour at a tertiary care hospital in Kolar, Karnataka, between December 2014 and October 2016, by Enzyme Linked Immunosorbent Assay (ELISA. Demographic, socio-economic, and obstetrical data along with exposure to risk factors among the participants were recorded. Two hundred and fifty one cord blood samples of the newborns of the above mothers were tested for anti-Toxoplasma IgM antibodies by µ capture ELISA. The validity of an IgM positive reaction was evaluated. The differences in proportions were analysed by the Chi-square test and the differences in means were analysed by the unpaired t-test. A p-value <0.05 was considered significant. Results: IgG antibodies to T. gondii could be detected in 53 (21.1% of the mothers tested; the titres ranged between 35 IU/ml – 350 IU/ml. Mothers from lower socio-economic strata had significantly higher prevalence as compared to mothers from middle classes. The seropositivity was not significantly associated with gravid status, literacy, occupation, exposure to cats, consumption of raw meat, salad, or drinking untreated water, gestational age, previous history of abortion or the mode of delivery. Cord blood samples from 5 (2 % of the newborns gave positive IgM reactions, but they were interpreted as false positives as there was no evidence of infection in their respective mothers or the baby lacked antibodies on follow up. Conclusion: About one fifth of

Modelling the role of transmission companies in the downstream European gas market

International Nuclear Information System (INIS)

Boots, M.A.; Rijkers, F.A.M.

2000-07-01

This paper describes the empirical model GASTALE and shows several analyses of the European gas market using this model. These analyses are mainly focused on the role of the downstream transmission companies. Producers of natural gas are assumed to form an oligopoly throughout the paper. Considering an oligopolistic transmission structure our model results show that the level of transmitters' profits strongly depends on the possibilities of discrimination on the border prices. If price discrimination by producers is allowed, these producers collect the main part of the margins on end-use prices. Without price discrimination the transmission companies collect most of the margins. Assuming an oligopolistic downstream structure, end-use prices converge to prices corresponding to perfect competition when the number of transmitters increases. Given the oligopolistic structure of the upstream industry, it is of importance to prevent (or abolish) monopolistic structures in the downstream gas market. In the case where oligopolistic competition between downstream gas companies cannot be prevented, vertical integration should be supported (or at least not be discouraged). 14 refs

Doubling transmission capacity in optical wireless system by antenna horizontal- and vertical-polarization multiplexing.

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Li, Xinying; Yu, Jianjun; Zhang, Junwen; Dong, Ze; Chi, Nan

2013-06-15

We experimentally demonstrate 2×56 Gb/s two-channel polarization-division-multiplexing quadrature-phase-shift-keying signal delivery over 80 km single-mode fiber-28 and 2 m Q-band (33-50 GHz) wireless link, adopting antenna horizontal- (H-) and vertical-polarization (V-polarization) multiplexing. At the wireless receiver, classic constant-modulus-algorithm equalization based on digital signal processing can realize polarization demultiplexing and remove the crosstalk at the same antenna polarization. By adopting antenna polarization multiplexing, the signal baud rate and performance requirements for optical and wireless devices can be reduced but at the cost of double antennas and devices, while wireless transmission capacity can also be increased but at the cost of stricter requirements for V-polarization. The isolation is only about 19 dB when V-polarization deviation approaches 10°, which will affect high-speed (>50 Gb/s) wireless delivery.

First isolation of Aedes flavivirus in the Western Hemisphere and evidence of vertical transmission in the mosquito Aedes (Stegomyia) albopictus (Diptera: Culicidae)

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Haddow, Andrew D., E-mail: adhaddow@gmail.com [Institute for Human Infections and Immunity, Center for Emerging Infectious Diseases and Biodefense, Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States); Guzman, Hilda; Popov, Vsevolod L. [Institute for Human Infections and Immunity, Center for Emerging Infectious Diseases and Biodefense, Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States); Wood, Thomas G.; Widen, Steven G. [Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States); Haddow, Alastair D. [Mercy Clinic, 2115 S. Fremont, Springfield, MO 65804 (United States); Tesh, Robert B.; Weaver, Scott C. [Institute for Human Infections and Immunity, Center for Emerging Infectious Diseases and Biodefense, Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States)

2013-06-05

We report here the first evidence of vertical transmission of Aedes flavivirus (AEFV) and its first isolation in the Western Hemisphere. AEFV strain SPFLD-MO-2011-MP6 was isolated in C6/36 cells from a pool of male Aedes albopictus mosquitoes that were reared to adults from larvae collected in southwest Missouri, USA, in 2011. Electron micrographs of the virus showed virions of approximately 45 nm in diameter with morphological characteristics associated with flaviviruses. The genomic sequence demonstrated that AEFV-SPFLD-MO-2011-MP6 shares a high degree of nucleotide and amino acid sequence identity with the AEFV Narita-21 strain, isolated in Japan in 2003. Intracerebral inoculation of newborn mice with the virus failed to produce observable illness or death and the virus did not replicate in vertebrate cells, consistent with a lack of vertebrate host range. - Highlights: ► The first report of Aedes flavivirus (AEFV) in the Western Hemisphere. ► The first evidence of vertical transmission of AEFV in mosquitoes. ► The first electron micrograph of AEFV. ► The first attempt to infect animals with AEFV.

First isolation of Aedes flavivirus in the Western Hemisphere and evidence of vertical transmission in the mosquito Aedes (Stegomyia) albopictus (Diptera: Culicidae)

International Nuclear Information System (INIS)

Haddow, Andrew D.; Guzman, Hilda; Popov, Vsevolod L.; Wood, Thomas G.; Widen, Steven G.; Haddow, Alastair D.; Tesh, Robert B.; Weaver, Scott C.

2013-01-01

We report here the first evidence of vertical transmission of Aedes flavivirus (AEFV) and its first isolation in the Western Hemisphere. AEFV strain SPFLD-MO-2011-MP6 was isolated in C6/36 cells from a pool of male Aedes albopictus mosquitoes that were reared to adults from larvae collected in southwest Missouri, USA, in 2011. Electron micrographs of the virus showed virions of approximately 45 nm in diameter with morphological characteristics associated with flaviviruses. The genomic sequence demonstrated that AEFV-SPFLD-MO-2011-MP6 shares a high degree of nucleotide and amino acid sequence identity with the AEFV Narita-21 strain, isolated in Japan in 2003. Intracerebral inoculation of newborn mice with the virus failed to produce observable illness or death and the virus did not replicate in vertebrate cells, consistent with a lack of vertebrate host range. - Highlights: ► The first report of Aedes flavivirus (AEFV) in the Western Hemisphere. ► The first evidence of vertical transmission of AEFV in mosquitoes. ► The first electron micrograph of AEFV. ► The first attempt to infect animals with AEFV

Systemic administration of antiretrovirals prior to exposure prevents rectal and intravenous HIV-1 transmission in humanized BLT mice.

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Paul W Denton

2010-01-01

Full Text Available Successful antiretroviral pre-exposure prophylaxis (PrEP for mucosal and intravenous HIV-1 transmission could reduce new infections among targeted high-risk populations including discordant couples, injection drug users, high-risk women and men who have sex with men. Targeted antiretroviral PrEP could be particularly effective at slowing the spread of HIV-1 if a single antiretroviral combination were found to be broadly protective across multiple routes of transmission. Therefore, we designed our in vivo preclinical study to systematically investigate whether rectal and intravenous HIV-1 transmission can be blocked by antiretrovirals administered systemically prior to HIV-1 exposure. We performed these studies using a highly relevant in vivo model of mucosal HIV-1 transmission, humanized Bone marrow/Liver/Thymus mice (BLT. BLT mice are susceptible to HIV-1 infection via three major physiological routes of viral transmission: vaginal, rectal and intravenous. Our results show that BLT mice given systemic antiretroviral PrEP are efficiently protected from HIV-1 infection regardless of the route of exposure. Specifically, systemic antiretroviral PrEP with emtricitabine and tenofovir disoproxil fumarate prevented both rectal (Chi square = 8.6, df = 1, p = 0.003 and intravenous (Chi square = 13, df = 1, p = 0.0003 HIV-1 transmission. Our results indicate that antiretroviral PrEP has the potential to be broadly effective at preventing new rectal or intravenous HIV transmissions in targeted high risk individuals. These in vivo preclinical findings provide strong experimental evidence supporting the potential clinical implementation of antiretroviral based pre-exposure prophylactic measures to prevent the spread of HIV/AIDS.

Knowledge and perceptions of HIV/AIDS and mother to child transmission among antenatal mothers at Nnamdi Azikiwe University Teaching hospital, Nnewi.

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Igwegbe, A O; Ilika, A L

2005-12-01

Knowledge of HIV/AIDS by pregnant mothers is very important in the prevention of mother to child transmission. This study evaluates the knowledge and perceptions of HIV/AIDS and mother to child transmission among pregnant women attending antenatal clinic at a University Teaching Hospital. Pre-tested questionnaires were interviewer administered to 312 pregnant women randomly selected at the antenatal clinic of the Nnamdi Azikiwe University Teaching Hospital Nnewi. The level of awareness of HIV/AIDS among antenatal mothers was very high (99%) and the main sources of information were radio (44.7%), television (38.8%), and print media (34.0%). Though majority (94.2%) was aware HIV infection can coexist with pregnancy, only 76.9% were aware of mother to child transmission. Transplacental (46.1%), breastfeeding (31.7%), and vaginal delivery (16.3%) were the commonly identified routes of vertical transmission. Surprisingly, eighteen respondents (5.8%) indicated that caesarean section is a possible route of vertical transmission. Though the percentage of HIV/AIDS knowledge is high, the level of knowledge and perceptions of mother to child transmission is inadequate. This suggests the need to scale up health education about mother to child transmission in our health facilities.

Imported Zika Virus in a European City: How to Prevent Local Transmission?

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Joan-Pau Millet

2017-07-01

Full Text Available Background: On February 1st 2016 the WHO declared the Zika Virus (ZIKV infection a worldwide public health emergency because of its rapid expansion and severe complications, such as Guillain-Barré Syndrome or microcephaly in newborn. The huge amount of people traveling to endemic areas and the presence of Aedes albopictus in Barcelona increase the risk of autochtonous transmission. The objective of this study was to describe the first ZIKV cases diagnosed in our city and to analyze the surveillance, prevention, and control measures implemented to avoid autochthonous transmission.Methods: An observational cross-sectional population-based study in Barcelona, Spain was performed.An analysis of the socio-demographic, epidemiological, clinical characteristics, and mosquito control activities of the ZIKV cases detected between January 1st and December 2016 was carried out using a specific ZIKV epidemiological survey of the Barcelona Public Health Agency.Results: A total of 118 notifications of possible ZIKV infections were received, and 44 corresponded to confirmed cases in Barcelona residents.Amongst these, the median age was 35 years and 57% were women. All cases were imported, 48% were Spanish-born and 52% foreign-born. Dominican Republic was the most visited country amongst foreign-born patients and Nicaragua amongst Spanish-born. The most frequent symptoms were exanthema, fever, and arthralgia. Among the 24 diagnosed women, 6 (25% were pregnant. There was one case of microcephaly outside Barcelona city. Entomological inspections were done at the homes of 19 cases (43.2% of the total and in 34 (77.3% public spaces. Vector activity was found in one case of the 44 confirmed cases, and 134 surveillance and vector control were carried out associated to imported ZIKV cases. In all cases prevention measures were recommended to avoid mosquito bites on infected cases.Conclusion: Epidemiological and entomological surveillance are essential for the

Knowledge and beliefs of international travellers about the transmission and prevention of HIV infection.

OpenAIRE

Allard, R; Lambert, G

1992-01-01

OBJECTIVES: To measure the perceived risk of acquired immunodeficiency syndrome (AIDS) among international travellers, to measure their knowledge of the transmission and prevention of HIV infection abroad and to identify some of the determinants of this knowledge. DESIGN: Survey. SETTING: Travellers' immunization clinic providing mostly primary preventive care to international travellers. PARTICIPANTS: All clients aged 18 to 50 years seen at the clinic between Oct. 2 and Dec. 21, 1989, before...

Upper-room ultraviolet light and negative air ionization to prevent tuberculosis transmission.

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A Roderick Escombe

2009-03-01

Full Text Available Institutional tuberculosis (TB transmission is an important public health problem highlighted by the HIV/AIDS pandemic and the emergence of multidrug- and extensively drug-resistant TB. Effective TB infection control measures are urgently needed. We evaluated the efficacy of upper-room ultraviolet (UV lights and negative air ionization for preventing airborne TB transmission using a guinea pig air-sampling model to measure the TB infectiousness of ward air.For 535 consecutive days, exhaust air from an HIV-TB ward in Lima, Perú, was passed through three guinea pig air-sampling enclosures each housing approximately 150 guinea pigs, using a 2-d cycle. On UV-off days, ward air passed in parallel through a control animal enclosure and a similar enclosure containing negative ionizers. On UV-on days, UV lights and mixing fans were turned on in the ward, and a third animal enclosure alone received ward air. TB infection in guinea pigs was defined by monthly tuberculin skin tests. All guinea pigs underwent autopsy to test for TB disease, defined by characteristic autopsy changes or by the culture of Mycobacterium tuberculosis from organs. 35% (106/304 of guinea pigs in the control group developed TB infection, and this was reduced to 14% (43/303 by ionizers, and to 9.5% (29/307 by UV lights (both p < 0.0001 compared with the control group. TB disease was confirmed in 8.6% (26/304 of control group animals, and this was reduced to 4.3% (13/303 by ionizers, and to 3.6% (11/307 by UV lights (both p < 0.03 compared with the control group. Time-to-event analysis demonstrated that TB infection was prevented by ionizers (log-rank 27; p < 0.0001 and by UV lights (log-rank 46; p < 0.0001. Time-to-event analysis also demonstrated that TB disease was prevented by ionizers (log-rank 3.7; p = 0.055 and by UV lights (log-rank 5.4; p = 0.02. An alternative analysis using an airborne infection model demonstrated that ionizers prevented 60% of TB infection and 51% of TB

Cost-effectiveness of quantitative hepatitis B virus surface antigen testing in pregnancy in predicting vertical transmission risk.

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Samadi Kochaksaraei, Golasa; Congly, Stephen E; Matwiy, Trudy; Castillo, Eliana; Martin, Steven R; Charlton, Carmen L; Coffin, Carla S

2016-11-01

Vertical transmission of hepatitis B virus (HBV) can occur despite immunoprophylaxis in mothers with high HBV DNA levels (>5-7 log 10 IU/ml). Quantitative hepatitis B surface antigen (qHBsAg) testing could be used as a surrogate marker to identify high viral load carriers, but there is limited data in pregnancy. We conducted a prospective observational study to determine the cost-effectiveness and utility of qHBsAg as a valid surrogate marker of HBV DNA. Pregnant patients with chronic hepatitis B were recruited from a tertiary referral centre. HBV DNA levels and qHBsAg were assessed in the second to third trimester. Statistical analysis was performed by Spearman's rank correlation and student's t-test. The cost-effectiveness of qHBsAg as compared to HBV DNA testing was calculated. Ninety nine women with 103 pregnancies, median age 32 years, 65% Asian, 23% African and 12% other [Hispanic, Caucasian] were enrolled. Overall, 23% (23/99) were HBV e Ag (HBeAg)-positive. A significant correlation between qHBsAg and HBV DNA levels was noted in HBeAg-positive patients (r = 0.79, P < 0.05) but not in HBeAg-negative patients (r = 0.17, P = 0.06). In receiver operating characteristic analysis, the optimal qHBsAg cut-off values for predicting maternal viraemia associated with immunoprophylaxis failure (i.e., HBV DNA ≥7 log 10 IU/ml) was 4.3 log 10 IU/ml (accuracy 98.7%, sensitivity 94.7%, specificity 94.4%) (95% CI, 97-100%, P < 0.05). Use of HBV DNA as compared to qHBsAg costs approximately $20 000 more per infection prevented. In resource poor regions, qHBsAg could be used as a more cost-effective marker for high maternal viraemia, and indicate when anti-HBV nucleos/tide analogue therapy should be used to prevent HBV immunoprophylaxis failure. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Measurement of the vertical infiltration parameters and water redistribution in LRd and LEa soils by gamma-ray transmission technique

International Nuclear Information System (INIS)

Souza, A.D.B. de; Saito, H.; Appoloni, C.R.; Coimbra, M.M.; Parreira, P.S.

1991-01-01

The properties of soil water diffusivity and soil hydraulic conductivity of two horizons (0-20 cm and 20-40 cm) from Latossolo Roxo distrofico (LRd) and Latossolo Vermelho escuro (LEa) soil samples, have been measured in laboratory through the vertical infiltration and redistribution of water in soil columns. The moisture profile as a function of time for each position in the soil column were obtained with the gamma-ray transmission technique, using a sup(241)Am gamma-ray source, a Na (I) T1 scintillation detector and gamma spectrometry standard electronic. (author)

Local Stability of AIDS Epidemic Model Through Treatment and Vertical Transmission with Time Delay

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Novi W, Cascarilla; Lestari, Dwi

2016-02-01

This study aims to explain stability of the spread of AIDS through treatment and vertical transmission model. Human with HIV need a time to positively suffer AIDS. The existence of a time, human with HIV until positively suffer AIDS can be delayed for a time so that the model acquired is the model with time delay. The model form is a nonlinear differential equation with time delay, SIPTA (susceptible-infected-pre AIDS-treatment-AIDS). Based on SIPTA model analysis results the disease free equilibrium point and the endemic equilibrium point. The disease free equilibrium point with and without time delay are local asymptotically stable if the basic reproduction number is less than one. The endemic equilibrium point will be local asymptotically stable if the time delay is less than the critical value of delay, unstable if the time delay is more than the critical value of delay, and bifurcation occurs if the time delay is equal to the critical value of delay.

Overview of revised measures to prevent malaria transmission by blood transfusion in France.

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Garraud, O; Assal, A; Pelletier, B; Danic, B; Kerleguer, A; David, B; Joussemet, M; de Micco, P

2008-10-01

Plasmodial transmission by blood donation is rare in non-endemic countries, but a very serious complication of blood transfusion. The French national blood service (Etablissement Français du Sang and Centre de Transfusion sanguine des Armees) intended to revise the measures to strengthen blood safety with regard to Plasmodiae as transmissible pathogens. To limit the risk of transmission during infusion, serious additive measures have been taken for more than a decade in France, which is the European country with the highest rate of exposure to imported plasmodial infections or malaria. These measures were revised and strengthened after the occurrence of a lethal transfusion-transmitted infection in 2002, but did not prevent another occurrence in 2006. This report examines the weaknesses of the systems and aims at emphasizing the safety measures already taken and addresses issues to best respond to that risk.

The optimal vertical structure in the electricity industry when the incumbent has a cost advantage

International Nuclear Information System (INIS)

Kurakawa, Yukihide

2013-01-01

This paper studies how the vertical structure of the electricity industry affects the social welfare when the incumbent has a cost advantage in generation relative to the entrants. The model consists of a generation sector and a transmission sector. In the generation sector the incumbent and entrants compete in a Cournot fashion taking as given the access charge to the transmission network set in advance by the regulator to maximize the social welfare. Two vertical structures, integration and separation, are considered. Under vertical separation the transmission network is established as an organization independent of every generator, whereas under vertical integration it is a part of the incumbent's organization. The optimal vertical structure is shown to depend on the number of entrants. If the number of entrants is smaller than a certain threshold, vertical separation is superior in welfare to vertical integration, and vice versa. This is because the choice of vertical structure produces a trade-off in the effects on competition promotion and production efficiency. If a break-even constraint is imposed in the transmission sector, however, vertical integration is shown to be always superior in welfare. - Highlights: • We examine the optimal vertical structure in the electricity industry. • We model a generation sector in which the incumbent has a cost advantage. • A trade-off between production efficiency and competition promotion occurs. • The optimal vertical structure depends on the number of entrants. • Vertical integration is always superior if a break-even constraint is imposed

Prevention Strategies Against HIV Transmission: A Proactive Approach.

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Carrion, Antonio J; Miles, Jovan D; Mosley, Juan F; Smith, Lillian L; Prather, April S; Gurley, Marcus M; Phan, Linh D; Everton, Emily C

2018-02-01

Human immunodeficiency virus (HIV) has now transformed into a manageable chronic condition. Highly active antiretroviral therapy (HAART) has proven efficacious at controlling the disease progression. Based on compelling evidence, the Department of Health and Human Services (DHHS) and the Infectious Disease Society of America (IDSA) developed guidelines for the management of persons infected with HIV. However, there are approximately 50 000 new cases of HIV in the United States each year. In this article, we review proactive methods to reduce the transmission of HIV, which include reinforcing patient education, gel-coated condoms that destroy HIV, HIV vaccinations, and adequately utilizing pre-exposure prophylaxis (PrEP), and post-exposure prophylaxis (PEP). Further development and consistent utilization of innovative prevention tools can significantly reduce the incidence of HIV infections regardless of HIV status.

The Hidden Habit of the Entomopathogenic Fungus Beauveria bassiana: First Demonstration of Vertical Plant Transmission

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Quesada-Moraga, Enrique; López-Díaz, Cristina; Landa, Blanca Beatriz

2014-01-01

Beauveria bassiana strain 04/01-Tip, obtained from a larva of the opium poppy stem gall wasp Iraella luteipes (Hymenoptera; Cynipidae), endophytically colonizes opium poppy (Papaver somniferum L.) plants and protects them against this pest. The goal of this study was to monitor the dynamics of endophytic colonization of opium poppy by B. bassiana after the fungus was applied to the seed and to ascertain whether the fungus is transmitted vertically via seeds. Using a species-specific nested PCR protocol and DNA extracted from surface-sterilised leaf pieces or seeds of B. bassiana-inoculated opium poppy plants, the fungus was detected within the plant beginning at the growth stage of rosette building and them throughout the entire plant growth cycle (about 120–140 days after sowing). The fungus was also detected in seeds from 50% of the capsules sampled. Seeds that showed positive amplification for B. bassiana were planted in sterile soil and the endophyte was again detected in more than 42% of the plants sampled during all plant growth stages. Beauveria bassiana was transmitted to seeds in 25% of the plants from the second generation that formed a mature capsule. These results demonstrate for the first time the vertical transmission of an entomopathogenic fungus from endophytically colonised maternal plants. This information is crucial to better understand the ecological role of entomopathogenic fungi as plant endophytes and may allow development of a sustainable and cost effective strategy for I. luteipes management in P. somniferum. PMID:24551242

The hidden habit of the entomopathogenic fungus Beauveria bassiana: first demonstration of vertical plant transmission.

Science.gov (United States)

Quesada-Moraga, Enrique; López-Díaz, Cristina; Landa, Blanca Beatriz

2014-01-01

Beauveria bassiana strain 04/01-Tip, obtained from a larva of the opium poppy stem gall wasp Iraella luteipes (Hymenoptera; Cynipidae), endophytically colonizes opium poppy (Papaver somniferum L.) plants and protects them against this pest. The goal of this study was to monitor the dynamics of endophytic colonization of opium poppy by B. bassiana after the fungus was applied to the seed and to ascertain whether the fungus is transmitted vertically via seeds. Using a species-specific nested PCR protocol and DNA extracted from surface-sterilised leaf pieces or seeds of B. bassiana-inoculated opium poppy plants, the fungus was detected within the plant beginning at the growth stage of rosette building and them throughout the entire plant growth cycle (about 120-140 days after sowing). The fungus was also detected in seeds from 50% of the capsules sampled. Seeds that showed positive amplification for B. bassiana were planted in sterile soil and the endophyte was again detected in more than 42% of the plants sampled during all plant growth stages. Beauveria bassiana was transmitted to seeds in 25% of the plants from the second generation that formed a mature capsule. These results demonstrate for the first time the vertical transmission of an entomopathogenic fungus from endophytically colonised maternal plants. This information is crucial to better understand the ecological role of entomopathogenic fungi as plant endophytes and may allow development of a sustainable and cost effective strategy for I. luteipes management in P. somniferum.

Challenges and Strategies for Prevention of Multidrug-Resistant Organism Transmission in Nursing Homes.

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Dumyati, Ghinwa; Stone, Nimalie D; Nace, David A; Crnich, Christopher J; Jump, Robin L P

2017-04-01

Nursing home residents are at high risk for colonization and infection with bacterial pathogens that are multidrug-resistant organisms (MDROs). We discuss challenges and potential solutions to support implementing effective infection prevention and control practices in nursing homes. Challenges include a paucity of evidence that addresses MDRO transmission during the care of nursing home residents, limited staff resources in nursing homes, insufficient infection prevention education in nursing homes, and perceptions by nursing home staff that isolation and contact precautions negatively influence the well being of their residents. A small number of studies provide evidence that specifically address these challenges. Their outcomes support a paradigm shift that moves infection prevention and control practices away from a pathogen-specific approach and toward one that focuses on resident risk factors.

Recent progress in immune-based interventions to prevent HIV-1 transmission to children.

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Voronin, Yegor; Jani, Ilesh; Graham, Barney S; Cunningham, Coleen K; Mofenson, Lynne M; Musoke, Philippa M; Permar, Sallie R; Scarlatti, Gabriella

2017-12-01

Globally, 150,000 new paediatric human immunodeficiency virus type 1 (HIV-1) infections occurred in 2015. There remain complex challenges to the global elimination of paediatric HIV-1 infection. Thus, for the global community to achieve elimination of new paediatric HIV-1 infections, innovative approaches need to be explored. Immune-based approaches to prevention of mother-to-child transmission (MTCT) may help fill some of the remaining gaps and provide new opportunities to achieve an AIDS-free generation. Immune-based interventions to prevent MTCT of HIV-1 may include paediatric HIV vaccines and passive immunization approaches. Recent discoveries providing evidence of robust immune responses to HIV in infants open new and exciting prospects for paediatric HIV vaccines. Moreover, successful vaccination of infants has a different set of requirements than vaccination of adults and may be easier to achieve. Proof-of-concept has been established over the last two decades that passively administered HIV-1 Env-specific monoclonal antibody (mAbs) can prevent chimeric simian human immunodeficiency virus (SHIV) transmission to newborn nonhuman primates. There has been tremendous progress in isolating and characterizing broadly neutralizing antibodies to HIV, and clinical testing of these antibodies for treatment and prevention in both infants and adults is a major effort in the field. Immune-based interventions need to be actively explored as they can provide critically important tools to address persistent challenges in MTCT prevention. It is a pivotal time for the field with active discussions on the best strategy to further reduce HIV infection of infants and accomplish the World Health Organization Fast-Track 2030 goals to eliminate new paediatric HIV infections. © 2017 The Authors. Journal of the International AIDS Society published by John Wiley & sons Ltd on behalf of the International AIDS Society.

HIV positive mothers' beliefs about mother-to-child transmission Creencias de las madres seropositivas respecto a la transmisión vertical del HIV Crenças das mães soropositivas ao HIV acerca da transmissão vertical da doença

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Lis Aparecida de Souza Neves

2006-10-01

Full Text Available Beliefs can influence health behavior. This qualitative study aimed to understand the beliefs that influence HIV positive mothers' behaviors towards prevention methods against mother-to-child transmission. Fourteen women were interviewed. Our research was based on the theoretical Health Belief Model, formed by the following dimensions: perceived susceptibility, perceived severity, perceived benefits and perceived obstacles. Data analysis showed reflections that evidence the paradox in the AIDS epidemic: knowledge does not change behavior; gender relations; fear of death; fear of stigma; financial problems; disbelief in the virus' existence. Identifying beliefs and understanding how to influence the conduction of the health problem can help services to promote patients' adherence.Las creencias son capaces de influenciar el comportamiento del hombre. El objetivo de este estudio cualitativo fue comprender las creencias que influencian el comportamiento de las madres HIV respecto a las medidas profilácticas de la transmisión vertical. Fueron entrevistadas 14 mujeres portadoras de HIV. Los datos fueron analizados utilizando como referencial teórico el Modelo de Creencias de la Salud, que es compuesto por las dimensiones de susceptibilidad percibida, severidad percibida, beneficios percibidos y barreras percibidas. Fueron observadas las contradicciones de la epidemia de SIDA: el conocimiento no muda comportamiento; miedo de la muerte; subestimación del HIV; dificultades financieras; no creer en la existencia del virus. Identificar y comprender las creencias puede ayudar los servicios de salud a promover la adhesión de la clientela.As crenças parecem influenciar diretamente nas atitudes dos seres humanos. Neste estudo qualitativo buscamos identificar as crenças que influenciam a adesão das mães portadoras do HIV às medidas profiláticas da transmissão vertical. Foram entrevistadas 14 mães soropositivas. A análise foi feita utilizando

Risk factors for secondary transmission of Shigella infection within households: implications for current prevention policy

NARCIS (Netherlands)

Boveé, Lian; Whelan, Jane; Sonder, Gerard J. B.; van Dam, Alje P.; van den Hoek, Anneke

2012-01-01

Background: Internationally, guidelines to prevent secondary transmission of Shigella infection vary widely. Cases, their contacts with diarrhoea, and those in certain occupational groups are frequently excluded from work, school, or daycare. In the Netherlands, all contacts attending pre-school

Healthcare workers and prevention of hepatitis C virus transmission: exploring knowledge, attitudes and evidence-based practices in hemodialysis units in Italy

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Bianco Aida

2013-02-01

Full Text Available Abstract Background Evidence exists regarding the full prevention of HCV transmission to hemodialysis patients by implementing universal precaution. However, little information is available regarding the frequency with which hospitals have adopted evidence-based practices for preventing HCV infection among hemodialysis patients. A cross-sectional survey has been conducted among nurses in Calabria region (Italy in order to acquire information about the level of knowledge, the attitudes and the frequencies of evidence-based practices that prevent hospital transmission of HCV. Methods All 37 hemodialysis units (HDU of Calabria were included in the study and all nurses were invited to participate in the study and to fill in a self-administered questionnaire. Results 90% of the nurses working in HDU participated in the study. Correct answers about HCV pattern of transmission ranged from 73.7% to 99.3% and were significantly higher in respondents who knew that isolation of HCV-infected patients is not recommended and among those who knew that previous bloodstream infections should be included in medical record and among nurses with fewer years of practice. Most correctly thought that evidence-based infection control measures provide adequate protection against transmission of bloodborne pathogens among healthcare workers. Positive attitude was significantly higher among more knowledgeable nurses. Self-reporting of appropriate handwashing procedures were significantly more likely in nurses who were aware that transmission of bloodborne pathogens among healthcare workers may be prevented through adoption of evidence-based practices and with a correct knowledge about HCV transmission patterns. Conclusions Behavior changes should be aimed at abandoning outdated practices and adopting and maintaining evidence-based practices. Initiatives focused at enabling and reinforcing adherence to effective prevention practices among nurses in HDU are strongly needed.

Barriers to control syphilis and HIV vertical transmission in the health care system in the city of Sao Paulo

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Valdete Maria Ramos

2014-12-01

Full Text Available OBJECTIVE: The objective of this study was to identify possible barriers to control vertical transmission of syphilis and HIV through the analysis of the orientation process of pregnant women from prenatal care to the obstetric center at an university hospital in Sao Paulo (Reference and their return (with their exposed babies for follow-up after hospital discharge (counter-reference. METHODS: It is a retrospective cross-sectional study including interviews with healthcare personnel. Pregnant women with syphilis and/or HIV-infection admitted for labor or miscarriage were identified from August 2006 to August 2007. Routine care for mothers and babies were analyzed. RESULTS: 56 pregnant women were identified: 43 were HIV-infected, 11 had syphilis and two were coinfected (syphilis/HIV; 22 health care professionals were interviewed. Prenatal care was identified in 91.1% of these women: 7/11 (63.6% with syphilis; 44/45 (97.8% HIV-infected or coinfected. The reference for delivery was satisfactory for 57.7% of the syphilis-infected women and 97.7% of the HIV-infected ones. The counter-reference was satisfactory for all babies and mothers at hospital discharge, besides the non-adherence to this recommendation. Interviews with health care professionals showed there are better routines for assisting and following-up pregnant women, puerperal women and HIV-infected or exposed babies than for those infected with syphilis. The epidemiological report and surveillance system are also better for HIV-infected patients. CONCLUSION: The difficulties in the reference and counter-reference system of these women and their babies are evident barriers to control the vertical transmission of these infectious diseases.

The first evidence for vertical transmission of [i]Babesia canis[/i] in a litter of Central Asian Shepherd dogs

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Ewa J Mierzejewska

2014-09-01

Full Text Available [b]Introduction and objective[/b]. Tick-borne infections constitute an increasing health problem in dogs and may lead to death, especially in young or elderly individuals. Canine babesiosis constitutes a serious health problem in dogs worldwide. The aim of the study was to verify the probability of vertical transmission of [i]Babesia canis[/i] between the bitch and the pups. [b]Materials and methods[/b]. In Autumn 2011, cases of babesiosis were diagnosed in a litter of 6-week-old puppies of a Central Asian Shepherd dog. Immediately following the first case of infection, blood samples were collected from all the pups in the litter (n=10 and from the female. Detection of Babesia infection was performed by molecular and microscopical techniques. [b]Results.[/b] The presence of[i] B. canis [/i]DNA was detected using PCR in three pups, presenting at the time or 24–48 hours later with babesiosis symptoms, and in their asymptomatic mother. The isolates derived from the pups and the female – 520 bp 18S rRNA gene fragment – were compared and analyzed. All isolates from the pups and their mother were identical and showed 100% homology with [i]B. canis[/i] group B (EU622793, supporting the same source of infection. Additionally, the USG of the peritoneal cavity was performed in the female, presenting evidence for splenomegaly. [b]Conclusions.[/b] On the basis of (1 the same timing of three pup cases; (2 the identical [i]B. canis[/i] sequences derived from all positive dogs; (3 evident splenomegaly in the asymptomatic female, this provides the first evidence of the vertical transmission of this piroplasm in dogs.

Stakeholders’ perceptions on factors influencing male involvement in prevention of mother to child transmission of HIV services in Blantyre, Malawi

OpenAIRE

Nyondo, Alinane Linda; Chimwaza, Angela Faith; Muula, Adamson Sinjani

2014-01-01

Background Male Involvement (MI) in the Prevention of Mother to Child Transmission (PMTCT) of Human Immunodeficiency Virus (HIV) services is essential in a patriarchal society where men are decision makers of the household. Male partners have a role in the woman’s risk of acquiring HIV, uptake of HIV testing and participation in Mother to Child Transmission (MTCT) prevention programmes. Although MI is important for uptake of PMTCT interventions, it remains low in Africa. The purpose of this s...

Prevention of mother-to-child transmission outcomes in the private sector in central Durban

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Shakira M Cassim

2010-11-01

Full Text Available The prevention of mother-to-child transmission (PMTCT programme in the central region of Ethekweni Metro, KwaZulu-Natal (Durban central area, was investigated. Data for all HIV-exposed infants from eight private paediatric practices seen between January 2004 and June 2005 were reviewed retrospectively. One hundred and one black African infants were born to 100 HIV-positive women of average age 30 years. Median viral loads and CD4 counts were 11 391 copies/ml and 426 cells/μl, respectively. Eighty-six women received HAART and 5 had no prophylaxis. Of the 92 infants tested, 2 were HIV positive, giving a transmission rate of 2.2%. Both their mothers had received suboptimal prophylaxis, and if they are excluded, the transmission rate falls to less than 1%, a rate consistent with those in the developed world.

A single-dose live-attenuated vaccine prevents Zika virus pregnancy transmission and testis damage.

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Shan, Chao; Muruato, Antonio E; Jagger, Brett W; Richner, Justin; Nunes, Bruno T D; Medeiros, Daniele B A; Xie, Xuping; Nunes, Jannyce G C; Morabito, Kaitlyn M; Kong, Wing-Pui; Pierson, Theodore C; Barrett, Alan D; Weaver, Scott C; Rossi, Shannan L; Vasconcelos, Pedro F C; Graham, Barney S; Diamond, Michael S; Shi, Pei-Yong

2017-09-22

Zika virus infection during pregnancy can cause congenital abnormities or fetal demise. The persistence of Zika virus in the male reproductive system poses a risk of sexual transmission. Here we demonstrate that live-attenuated Zika virus vaccine candidates containing deletions in the 3' untranslated region of the Zika virus genome (ZIKV-3'UTR-LAV) prevent viral transmission during pregnancy and testis damage in mice, as well as infection of nonhuman primates. After a single-dose vaccination, pregnant mice challenged with Zika virus at embryonic day 6 and evaluated at embryonic day 13 show markedly diminished levels of viral RNA in maternal, placental, and fetal tissues. Vaccinated male mice challenged with Zika virus were protected against testis infection, injury, and oligospermia. A single immunization of rhesus macaques elicited a rapid and robust antibody response, conferring complete protection upon challenge. Furthermore, the ZIKV-3'UTR-LAV vaccine candidates have a desirable safety profile. These results suggest that further development of ZIKV-3'UTR-LAV is warranted for humans.Zika virus infection can result in congenital disorders and cause disease in adults, and there is currently no approved vaccine. Here Shan et al. show that a single dose of a live-attenuated Zika vaccine prevents infection, testis damage and transmission to the fetus during pregnancy in different animal models.

Prevention of post-transfusion hepatitis c transmission through donor blood and its components

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A. V. Chechetkin

2015-01-01

Full Text Available The aim of organizational aspects of preventing the transmission of hepatitis C virus with donor blood and its components.Materials and methods. An activity of the blood service establishments in Russia for the prevention of HCV infection through transfusion of blood and its components on the basis of the analysis of sectoral statistical surveys was studied.Results. The frequency of detection of antibodies to hepatitis C virus in blood donors and its components during 2009–2013 decreased by more than 1,5 times. The percentage of donors who have identified markers of hepatitis C virus was significantly different in different regions: from 0,51% to 1,36%. The activity of the blood service implemented method of plasma quarantine resulting annually rejected from 0,32% to 0,23% as a result of the identified markers of HCV. Pathogen inactivated plasma volume increased in 3 times, the platelet concentrate in 3,2 times.Conclusion. To ensure the safety of donated blood and its components in the blood service effectively the modern technology use for to prevention transmission of the HCV: quarantine of plasma, donor selection and development, inactivation of pathogens. The degree of implementation in practice of nonpaid voluntary blood transfusions significantly increased and is characterized by regional features in recent years .

Recognising and managing increased HIV transmission risk in newborns

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Max Kroon

2015-05-01

Full Text Available Prevention of mother-to-child transmission (PMTCT programmes have improved maternalhealth outcomes and reduced the incidence of paediatric HIV, resulting in improved childhealth and survival. Nevertheless, high-risk vertical exposures remain common and areresponsible for a high proportion of transmissions. In the absence of antiretrovirals (ARVs,an 8- to 12-hour labour has approximately the same 15% risk of transmission as 18 monthsof mixed feeding. The intensity of transmission risk is highest during labour and delivery;however, the brevity of this intra-partum period lends itself to post-exposure interventions toreduce such risk. There is good evidence that infant post-exposure prophylaxis (PEP reducesintra-partum transmission even in the absence of maternal prophylaxis. Recent reports suggestthat infant combination ARV prophylaxis (cARP is more efficient at reducing intra-partumtransmission than a single agent in situations of minimal pre-labour prophylaxis. Guidelinesfrom the developed world have incorporated infant cARP for increased-risk scenarios. Incontrast, recent guidelines for low-resource settings have rightfully focused on reducingpostnatal transmission to preserve the benefits of breastfeeding, but have largely ignored thepotential of augmented infant PEP for reducing intra-partum transmissions. Minimal prelabourprophylaxis, poor adherence in the month prior to delivery, elevated maternal viralload at delivery, spontaneous preterm labour with prolonged rupture of membranes andchorioamnionitis are simple clinical criteria that identify increased intra-partum transmissionrisk. In these increased-risk scenarios, transmission frequency may be halved by combiningnevirapine and zidovudine as a form of boosted infant PEP. This strategy may be important toreduce intra-partum transmissions when PMTCT is suboptimal.

Partner testing, linkage to care, and HIV-free survival in a program to prevent parent-to-child transmission of HIV in the Highlands of Papua New Guinea

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Carmone, Andy; Bomai, Korai; Bongi, Wayaki; Frank, Tarua Dale; Dalepa, Huleve; Loifa, Betty; Kiromat, Mobumo; Das, Sarthak; Franke, Molly F.

2014-01-01

Background To eliminate new pediatric HIV infections, interventions that facilitate adherence, including those that minimize stigma, enhance social support, and mitigate the influence of poverty, will likely be required in addition to combination antiretroviral therapy (ART). We examined the relationship between partner testing and infant outcome in a prevention of parent-to-child transmission of HIV program, which included a family-centered case management approach and a supportive environment for partner disclosure and testing. Design We analyzed routinely collected data for women and infants who enrolled in the parent-to-child transmission of HIV program at Goroka Family Clinic, Eastern Highlands Provincial Hospital, Papua New Guinea, from 2007 through 2011. Results Two hundred and sixty five women were included for analysis. Of these, 226 (85%) had a partner, 127 (56%) of whom had a documented HIV test. Of the 102 HIV-infected partners, 81 (79%) had been linked to care. In adjusted analyses, we found a significantly higher risk of infant death, infant HIV infection, or loss to follow-up among mother–infant pairs in which the mother reported having no partner or a partner who was not tested or had an unknown testing status. In a second multivariable analysis, infants born to women with more time on ART or who enrolled in the program in later years experienced greater HIV-free survival. Conclusions In a program with a patient-oriented and family-centered approach to prevent vertical HIV transmission, the majority of women's partners had a documented HIV test and, if positive, linkage to care. Having a tested partner was associated with program retention and HIV-free survival for infants. Programs aiming to facilitate diagnosis disclosure, partner testing, and linkage to care may contribute importantly to the elimination of pediatric HIV. PMID:25172429

Vertical Transmission of Bacterial Eye Infections, Angola, 2011–2012

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Alexandre, Isabel; Martínez, Prudencio; Sanz, Iván; Rodriguez-Fernandez, Ana; Fernandez, Itziar; Pastor, Jose Carlos; Ortiz de Lejarazu, Raúl

2015-01-01

To determine transmission rates for neonatal conjunctivitis causative microorganisms in Angola, we analyzed 312 endocervical and 255 conjunctival samples from mothers and newborns, respectively, during 2011–2012. Transmission rates were 50% for Chlamydia trachomatis and Neisseria gonorrhoeae and 10.5% for Mycoplasma genitalium. Possible pathogenic effects of M. genitalium in children’s eyes are unknown. PMID:25695394

Extended-Spectrum-Beta-Lactamase- and Plasmid-Encoded Cephamycinase-Producing Enterobacteria in the Broiler Hatchery as a Potential Mode of Pseudo-Vertical Transmission.

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Projahn, Michaela; Daehre, Katrin; Roesler, Uwe; Friese, Anika

2017-01-01

Antimicrobial resistance through extended-spectrum beta-lactamases (ESBLs) and transferable (plasmid-encoded) cephamycinases (pAmpCs) represents an increasing problem in human and veterinary medicine. The presence of ESBL-/pAmpC-producing commensal enterobacteria in farm animals, such as broiler chickens, is considered one possible source of food contamination and could therefore also be relevant for human colonization. Studies on transmission routes along the broiler production chain showed that 1-day-old hatchlings are already affected. In this study, ESBL-/pAmpC-positive broiler parent flocks and their corresponding eggs, as well as various environmental and air samples from the hatchery, were analyzed. The eggs were investigated concerning ESBL-/pAmpC-producing enterobacteria on the outer eggshell surface (before/after disinfection), the inner eggshell surface, and the egg content. Isolates were analyzed concerning their species, their phylogroup in the case of Escherichia coli strains, the respective resistance genes, and the phenotypical antibiotic resistance. Of the tested eggs, 0.9% (n = 560) were contaminated on their outer shell surface. Further analyses using pulsed-field gel electrophoresis showed a relationship of these strains to those isolated from the corresponding parent flocks, which demonstrates a pseudo-vertical transfer of ESBL-/pAmpC-producing enterobacteria into the hatchery. Resistant enterobacteria were also found in environmental samples from the hatchery, such as dust or surfaces which could pose as a possible contamination source for the hatchlings. All 1-day-old chicks tested negative directly after hatching. The results show a possible entry of ESBL-/pAmpC-producing enterobacteria from the parent flocks into the hatchery; however, the impact of the hatchery on colonization of the hatchlings seems to be low. ESBL-/pAmpC-producing enterobacteria occur frequently in broiler-fattening farms. Recent studies investigated the prevalence and

Analysis of nevirapine (NVP) resistance in Ugandan infants who were HIV infected despite receiving single-Dose (SD) NVP versus SD NVP plus daily NVP up to 6 weeks of age to prevent HIV vertical transmission.

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Church, Jessica D; Omer, Saad B; Guay, Laura A; Huang, Wei; Lidstrom, Jessica; Musoke, Philippa; Mmiro, Francis; Jackson, J Brooks; Eshleman, Susan H

2008-10-01

Single-dose nevirapine (SD NVP) at birth plus NVP prophylaxis for the infant up to 6 weeks of age is superior to SD NVP alone for prevention of vertical transmission of human immunodeficiency virus (HIV) through breastfeeding. We analyzed NVP resistance in HIV-infected Ugandan infants who received either SD NVP or extended NVP prophylaxis. We tested plasma HIV by using a genotyping assay (ViroSeq; Celera Diagnostics), a phenotypic resistance assay (PhenoSense; Monogram Biosciences), and sensitive point mutation assay (LigAmp, for K103N, Y181C, and G190A). When infants were 6 weeks old, ViroSeq detected NVP resistance in a higher proportion of infants in the extended NVP arm than in the SD NVP arm (21 of 25 [84%] vs. 12 of 24 [50%]; P = .01). Similar results were obtained with LigAmp and PhenoSense. In both study arms, infants who were HIV infected at birth frequently had NVP resistance detected. In contrast, infants in the extended NVP arm who were HIV infected after birth were more likely to have resistance detected at 6 weeks, compared with infants in the SD NVP arm. The use of extended NVP prophylaxis was also associated with detection of NVP resistance by ViroSeq at 6 months (7 of 7 [100%] infants in the extended NVP arm had resistance detected, compared with 1 of 6 [16.7%] infants in the SD NVP arm; P = .005). The use of extended NVP prophylaxis was associated with increased selection for and persistence of NVP resistance in HIV-infected Ugandan infants.

Incidence of vertical phoria on postural control during binocular vision: what perspective for prevention to nonspecific chronic pain management?

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Matheron, Eric; Kapoula, Zoï

2015-01-01

Vertical heterophoria (VH) is the latent vertical misalignment of the eyes when the retinal images are dissociated, vertical orthophoria (VO) when there is no misalignment. Studies on postural control, during binocular vision in upright stance, reported that healthy subjects with small VH vs. VO are less stable, but the experimental cancellation of VH with an appropriate prism improves postural stability. The same behavior was recorded in nonspecific chronic back pain subjects, all with VH. It was hypothesized that, without refraction problems, VH indicates a perturbation of the somaesthetic cues required in the sensorimotor loops involved in postural control and the capacity of the CNS to optimally integrate these cues, suggesting prevention possibilities. Sensorimotor conflict can induce pain and modify sensory perception in some healthy subjects; some nonspecific pain or chronic pain could result from such prolonged conflict in which VH could be a sign, with new theoretical and clinical implications.

Knowledge, perceptions, and practices of methicillin-resistant Staphylococcus aureus transmission prevention among health care workers in acute-care settings.

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Seibert, Dorothy J; Speroni, Karen Gabel; Oh, Kyeung Mi; DeVoe, Mary C; Jacobsen, Kathryn H

2014-03-01

Health care workers (HCWs) play a critical role in prevention of health care-associated infections such as methicillin-resistant Staphylococcus aureus (MRSA), but glove and gown contact precautions and hand hygiene may not be consistently used with vulnerable patients. A cross-sectional survey of MRSA knowledge, attitudes/perceptions, and practices among 276 medical, nursing, allied health, and support services staff at an acute-care hospital in the eastern United States was completed in 2012. Additionally, blinded observations of hand hygiene behaviors of 104 HCWs were conducted. HCWs strongly agreed that preventive behaviors reduce the spread of MRSA. The vast majority reported that they almost always engage in preventive practices, but observations of hand hygiene found lower rates of adherence among nearly all HCW groups. HCWs who reported greater comfort with telling others to take action to prevent MRSA transmission were significantly more likely to self-report adherence to recommended practices. It is important to reduce barriers to adherence with preventive behaviors and to help all HCWs, including support staff who do not have direct patient care responsibilities, to translate knowledge about MRSA transmission prevention methods into consistent adherence of themselves and their coworkers to prevention guidelines. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Vertically transmitted rhabdoviruses are found across three insect families and have dynamic interactions with their hosts.

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Longdon, Ben; Day, Jonathan P; Schulz, Nora; Leftwich, Philip T; de Jong, Maaike A; Breuker, Casper J; Gibbs, Melanie; Obbard, Darren J; Wilfert, Lena; Smith, Sophia C L; McGonigle, John E; Houslay, Thomas M; Wright, Lucy I; Livraghi, Luca; Evans, Luke C; Friend, Lucy A; Chapman, Tracey; Vontas, John; Kambouraki, Natasa; Jiggins, Francis M

2017-01-25

A small number of free-living viruses have been found to be obligately vertically transmitted, but it remains uncertain how widespread vertically transmitted viruses are and how quickly they can spread through host populations. Recent metagenomic studies have found several insects to be infected with sigma viruses (Rhabdoviridae). Here, we report that sigma viruses that infect Mediterranean fruit flies (Ceratitis capitata), Drosophila immigrans, and speckled wood butterflies (Pararge aegeria) are all vertically transmitted. We find patterns of vertical transmission that are consistent with those seen in Drosophila sigma viruses, with high rates of maternal transmission, and lower rates of paternal transmission. This mode of transmission allows them to spread rapidly in populations, and using viral sequence data we found the viruses in D. immigrans and C. capitata had both recently swept through host populations. The viruses were common in nature, with mean prevalences of 12% in C. capitata, 38% in D. immigrans and 74% in P. aegeria We conclude that vertically transmitted rhabdoviruses may be widespread in a broad range of insect taxa, and that these viruses can have dynamic interactions with their hosts. © 2017 The Authors.

Vertically transmitted rhabdoviruses are found across three insect families and have dynamic interactions with their hosts

Science.gov (United States)

Day, Jonathan P.; Schulz, Nora; Leftwich, Philip T.; de Jong, Maaike A.; Wilfert, Lena; Smith, Sophia C. L.; McGonigle, John E.; Houslay, Thomas M.; Livraghi, Luca; Evans, Luke C.; Friend, Lucy A.; Vontas, John; Kambouraki, Natasa

2017-01-01

A small number of free-living viruses have been found to be obligately vertically transmitted, but it remains uncertain how widespread vertically transmitted viruses are and how quickly they can spread through host populations. Recent metagenomic studies have found several insects to be infected with sigma viruses (Rhabdoviridae). Here, we report that sigma viruses that infect Mediterranean fruit flies (Ceratitis capitata), Drosophila immigrans, and speckled wood butterflies (Pararge aegeria) are all vertically transmitted. We find patterns of vertical transmission that are consistent with those seen in Drosophila sigma viruses, with high rates of maternal transmission, and lower rates of paternal transmission. This mode of transmission allows them to spread rapidly in populations, and using viral sequence data we found the viruses in D. immigrans and C. capitata had both recently swept through host populations. The viruses were common in nature, with mean prevalences of 12% in C. capitata, 38% in D. immigrans and 74% in P. aegeria. We conclude that vertically transmitted rhabdoviruses may be widespread in a broad range of insect taxa, and that these viruses can have dynamic interactions with their hosts. PMID:28100819

Prevention of mother-to-child transmission of HIV: Postpartum adherence to Option B+ until 18 months in Western Uganda.

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Decker, Sarah; Rempis, Eva; Schnack, Alexandra; Braun, Vera; Rubaihayo, John; Busingye, Priscilla; Tumwesigye, Nazarius Mbona; Harms, Gundel; Theuring, Stefanie

2017-01-01

Since 2012, the WHO recommends Option B+ for the prevention of mother-to-child transmission of HIV. This approach entails the initiation of lifelong antiretroviral therapy in all HIV-positive pregnant women, also implying protection during breastfeeding for 12 months or longer. Research on long-term adherence to Option B+ throughout breastfeeding is scarce to date. Therefore, we conducted a prospective observational cohort study in Fort Portal, Western Uganda, to assess adherence to Option B+ until 18 months postpartum. In 2013, we recruited 67 HIV-positive, Option B+ enrolled women six weeks after giving birth and scheduled them for follow-up study visits after six, twelve and 18 months. Two adherence measures, self-reported drug intake and amount of drug refill visits, were combined to define adherence, and were assessed together with feeding information at all study visits. At six months postpartum, 51% of the enrolled women were considered to be adherent. Until twelve and 18 months postpartum, adherence for the respective follow-up interval decreased to 19% and 20.5% respectively. No woman was completely adherent until 18 months. At the same time, 76.5% of the women breastfed for ≥12 months. Drug adherence was associated with younger age (ptravel costs (p = 0.02), and lower number of previous deliveries (p = 0.04). Long-term adherence to Option B+ seems to be challenging. Considering that in our cohort, prolonged breastfeeding until ≥12 months was widely applied while postpartum adherence until the end of breastfeeding was poor, a potential risk of postpartum vertical transmission needs to be taken seriously into account for Option B+ implementation.

Prevention of mother-to-child transmission of HIV: Postpartum adherence to Option B+ until 18 months in Western Uganda.

Directory of Open Access Journals (Sweden)

Sarah Decker

Full Text Available Since 2012, the WHO recommends Option B+ for the prevention of mother-to-child transmission of HIV. This approach entails the initiation of lifelong antiretroviral therapy in all HIV-positive pregnant women, also implying protection during breastfeeding for 12 months or longer. Research on long-term adherence to Option B+ throughout breastfeeding is scarce to date. Therefore, we conducted a prospective observational cohort study in Fort Portal, Western Uganda, to assess adherence to Option B+ until 18 months postpartum. In 2013, we recruited 67 HIV-positive, Option B+ enrolled women six weeks after giving birth and scheduled them for follow-up study visits after six, twelve and 18 months. Two adherence measures, self-reported drug intake and amount of drug refill visits, were combined to define adherence, and were assessed together with feeding information at all study visits. At six months postpartum, 51% of the enrolled women were considered to be adherent. Until twelve and 18 months postpartum, adherence for the respective follow-up interval decreased to 19% and 20.5% respectively. No woman was completely adherent until 18 months. At the same time, 76.5% of the women breastfed for ≥12 months. Drug adherence was associated with younger age (p<0.01, lower travel costs (p = 0.02, and lower number of previous deliveries (p = 0.04. Long-term adherence to Option B+ seems to be challenging. Considering that in our cohort, prolonged breastfeeding until ≥12 months was widely applied while postpartum adherence until the end of breastfeeding was poor, a potential risk of postpartum vertical transmission needs to be taken seriously into account for Option B+ implementation.

[Initial evaluation of a programme to prevent mother-to-child transmission of human immunodeficiency virus infection in Equatorial Guinea].

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Badillo-Navarro, Katie; Prieto-Tato, Luis; Obiang-Esomoyo, Jacinta; Avedillo-Jiménez, Pedro; Vargas-Brizuela, Antonio; Rojo-Conejo, Pablo

2014-01-01

The prevalence of human immunodeficiency virus (HIV)-infected pregnant women in Equatorial Guinea (EG) has been reported as 7.3%. In 2008 an updated version of the PMTCT protocol was accepted according to the current WHO guidelines. The aim of this study was to describe the characteristics and outcome of children exposed to HIV after the introduction of the protocol. A retrospective review was conducted on the clinical characteristics of the infants born to HIV-infected mothers in the Hospital Regional de Bata and Primary Health Care Centre Maria Rafols in Bata (EG) between June 2008 and November 2011. The diagnosis of HIV infection in children was based on rapid serology tests. A total of 103 children were included, of which 47 were males. Fifty three patients (51%) completed the follow-up (51%). Fourteen children (26%) were diagnosed with HIV infection (11 presumptive diagnosis, 3 due to persistence of antibodies at 18 months). Six children (12%) died before a definitive diagnosis. Just over than half (52%) of mothers received antiretroviral therapy (ART) during pregnancy. The transmission rate in children whose mothers received ART was 16% (3/19), compared with 43% (10/23) in children whose mothers did not receive it. Only one child was infected (8%) when the mother received ART, and child received postnatal prophylaxis. The PMTCT protocol compliance was still very low. Antiretroviral therapy in pregnant women decreased the rate of vertical transmission, but the rate still remains very high. Many children were lost to follow-up. Strategies to prevent loss to follow-up and methods for earlier virological diagnostic are needed. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Multiple ways to prevent transmission of paternal mitochondrial DNA for maternal inheritance in animals.

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Sato, Ken; Sato, Miyuki

2017-10-01

Mitochondria contain their own DNA (mtDNA). In most sexually reproducing organisms, mtDNA is inherited maternally (uniparentally); this type of inheritance is thus referred to as 'maternal (uniparental) inheritance'. Recent studies have revealed various mechanisms to prevent the transmission of sperm-derived paternal mtDNA to the offspring, thereby ensuring maternal inheritance of mtDNA. In the nematode Caenorhabditis elegans, paternal mitochondria and their mtDNA degenerate almost immediately after fertilization and are selectively degraded by autophagy, which is referred to as 'allophagy' (allogeneic [non-self] organelle autophagy). In the fruit fly Drosophila melanogaster, paternal mtDNA is largely eliminated by an endonuclease G-mediated mechanism. Paternal mitochondria are subsequently removed by endocytic and autophagic pathways after fertilization. In many mammals, including humans, paternal mitochondria enter fertilized eggs. However, the fate of paternal mitochondria and their mtDNA in mammals is still a matter of debate. In this review, we will summarize recent knowledge on the molecular mechanisms underlying the prevention of paternal mtDNA transmission, which ensures maternal mtDNA inheritance in animals. © The Authors 2017. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

Strategic investment in merchant transmission: The impact of capacity utilization rules

International Nuclear Information System (INIS)

Boffa, Federico; Pingali, Viswanath; Sala, Francesca

2015-01-01

In this paper we look at the relative merits of two capacity utilization regimes in the merchant electricity transmission network: Must offer (Mo) where the entire capacity installed has to be made available for transmission and Non Must Offer (NMo) where some capacity could be withheld. We look at two specific cases: (i) demand for transmission varies across time, and (ii) vertical integration is allowed between investors in transmission network and electricity generators. In the case of time-varying demand under Mo, we find that a monopolist may underinvest in transmission when compared to NMo, although NMo may lead to more capacity withholding. In the case of vertical integration, we find that when the market power is with the generators of the exporting node, without vertical integration no welfare-enhancing merchant investment would occur, neither under Mo nor NMo. Further, if the generators in the importing node have market power, in case vertical integration is allowed, Mo is better than NMo. Finally, we also argue that the incentive to collude among various transmission network investors is mitigated with Mo in place. -- Highlights: •We model merits of Must offer (Mo) versus non-Must offer (NMo) regimes. •With fluctuating demand, NMo in general may generate more investment in capacity. •At the same time it may reduce capacity utilization. •With market power in the inefficient generating node, Mo is welfare-enhancing. •Collusion is mitigated with 'must offer' regime in place

An interactive multimedia program to prevent HIV transmission in men with intellectual disability.

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Wells, Jennifer; Clark, Khaya; Sarno, Karen

2014-05-01

The efficacy of a computer-based interactive multimedia HIV/AIDS prevention program for men with intellectual disability (ID) was examined using a quasi-experimental within-subjects design. Thirty-seven men with mild to moderate intellectual disability evaluated the program. The pretest and posttest instruments assessed HIV/AIDS knowledge (high-risk fluids, HIV transmission, and condom facts) and condom application skills. All outcome measures showed statistically significant gains from pretest to posttest, with medium to large effect sizes. In addition, a second study was conducted with twelve service providers who work with men with ID. Service providers reviewed the HIV/AIDS prevention program, completed a demographics questionnaire, and a program satisfaction survey. Overall, service providers rated the program highly on several outcome measures (stimulation, relevance, and usability).

Antenatal interventions for preventing the transmission of cytomegalovirus (CMV) from the mother to fetus during pregnancy and adverse outcomes in the congenitally infected infant.

LENUS (Irish Health Repository)

McCarthy, Fergus P

2012-01-31

BACKGROUND: Cytomegalovirus (CMV) is a herpesvirus and the most common cause of congenital infection in developed countries. Congenital CMV infection can have devastating consequences to the fetus. The high incidence and the serious morbidity associated with congenital CMV infection emphasise the need for effective interventions to prevent the antenatal transmission of CMV infection. OBJECTIVES: The aim of this review was to assess the benefits and harms of interventions used during pregnancy to prevent mother to fetus transmission of CMV infection. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group\\'s Trials Register (31 December 2010). SELECTION CRITERIA: All randomised controlled trials (RCTs) and quasi RCTs investigating antenatal interventions for preventing the transmission of CMV from the mother to fetus during pregnancy and adverse outcomes in the congenitally infected infant. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for inclusion. MAIN RESULTS: We identified six studies from the search. None of these studies met the pre-defined criteria for inclusion in this review. AUTHORS\\' CONCLUSIONS: To date, no RCTs are available that examine antenatal interventions for preventing the transmission of CMV from the infected mother to fetus during pregnancy and adverse outcomes in the congenitally infected infant. Further research is needed to assess the efficacy of interventions aimed at preventing the transmission of CMV from the mother to fetus during pregnancy including a long-term follow-up of exposed infants and a cost effective analysis.

Towards an optimal transmission system

International Nuclear Information System (INIS)

Calviou, M.

2005-01-01

This presentation provided background on National Grid USA and discussed transmission investment in the United States (US) and United Kingdom. It also discussed barriers to transmission investments and improvements, thoughts on solutions and a long-term vision. The presentation identified that transmission investment should follow from clear reliability rules designed to promote better operation and management; investment does not necessarily mean new rights-of-way; and transmission investment should target benefits to customers. It was stated that US transmission investment levels have decreased. A comparison between US and UK transmission investment was presented along with a chart of increasing US congestion costs. Barriers to investment in US transmission include vertical integration; misperception of transmission as a market product; federal and state jurisdiction issues; fragmentation in transmission ownership and operation; rate cap based plans that impact transmission; lack of clarity in cost allocation; and the site selection process. Possible solutions include policy and incentives, promoting independence and resolving structural issues. tabs., figs

Preventing HIV transmission in Chinese internal migrants: a behavioral approach.

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Liu, Xiaona; Erasmus, Vicki; Sun, Xinying; Cai, Rui; Shi, Yuhui; Richardus, Jan Hendrik

2014-01-01

This study is a step towards a behavioral intervention to prevent HIV transmission among Chinese internal migrants. To explore important and changeable determinants of condom use and inspect effective and feasible methods to increase condom use for the target population, we conducted a three-round web-based Delphi study among a panel of 62 experts between October 2012 and March 2013. The panelists were purposely selected using a stepwise procedure to represent topic-related areas of expertise. The response rate per round ranges from 21% to 81%. The panelists identified 19 possible determinants of condom use and reported 16 intervention methods they considered successful. They agreed that attitude towards condom use was the most important and changeable determinant, while applying behavioral theory, increasing sexual education and condom access, performing worksite health promotion, detecting risk factors, and working closely with relevant organizations and the government were effective and feasible methods to increase condom use among internal migrants in China. In conclusion, results of this study highlight the importance of attitude in changing condom use and underscore the need to apply behavior theory and integrate multiple educational approaches for developing behavioral HIV prevention interventions targeting internal migrants in China.

Preventing HIV Transmission in Chinese Internal Migrants: A Behavioral Approach

Science.gov (United States)

Erasmus, Vicki; Sun, Xinying; Shi, Yuhui; Richardus, Jan Hendrik

2014-01-01

This study is a step towards a behavioral intervention to prevent HIV transmission among Chinese internal migrants. To explore important and changeable determinants of condom use and inspect effective and feasible methods to increase condom use for the target population, we conducted a three-round web-based Delphi study among a panel of 62 experts between October 2012 and March 2013. The panelists were purposely selected using a stepwise procedure to represent topic-related areas of expertise. The response rate per round ranges from 21% to 81%. The panelists identified 19 possible determinants of condom use and reported 16 intervention methods they considered successful. They agreed that attitude towards condom use was the most important and changeable determinant, while applying behavioral theory, increasing sexual education and condom access, performing worksite health promotion, detecting risk factors, and working closely with relevant organizations and the government were effective and feasible methods to increase condom use among internal migrants in China. In conclusion, results of this study highlight the importance of attitude in changing condom use and underscore the need to apply behavior theory and integrate multiple educational approaches for developing behavioral HIV prevention interventions targeting internal migrants in China. PMID:25610903

Teaching and the life history of cultural transmission in Fijian villages.

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Kline, Michelle A; Boyd, Robert; Henrich, Joseph

2013-12-01

Much existing literature in anthropology suggests that teaching is rare in non-Western societies, and that cultural transmission is mostly vertical (parent-to-offspring). However, applications of evolutionary theory to humans predict both teaching and non-vertical transmission of culturally learned skills, behaviors, and knowledge should be common cross-culturally. Here, we review this body of theory to derive predictions about when teaching and non-vertical transmission should be adaptive, and thus more likely to be observed empirically. Using three interviews conducted with rural Fijian populations, we find that parents are more likely to teach than are other kin types, high-skill and highly valued domains are more likely to be taught, and oblique transmission is associated with high-skill domains, which are learned later in life. Finally, we conclude that the apparent conflict between theory and empirical evidence is due to a mismatch of theoretical hypotheses and empirical claims across disciplines, and we reconcile theory with the existing literature in light of our results.

Transplacental transmission of Leishmania infantum as a means for continued disease incidence in North America.

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Boggiatto, Paola Mercedes; Gibson-Corley, Katherine Nicole; Metz, Kyle; Gallup, Jack Michael; Hostetter, Jesse Michael; Mullin, Kathleen; Petersen, Christine Anne

2011-04-12

Dogs are the predominant domestic reservoir for human L. infantum infection. Zoonotic visceral leishmaniasis (ZVL) is an emerging problem in some U.S. dog breeds, with an annual quantitative PCR prevalence of greater than 20% within an at-risk Foxhound population. Although classically Leishmania is transmitted by infected sand flies and phlebotomine sand flies exist in the United States, means of ongoing L. infantum transmission in U.S. dogs is currently unknown. Possibilities include vertical (transplacental/transmammary) and horizontal/venereal transmission. Several reports have indicated that endemic ZVL may be transmitted vertically. Our aims for this present study were to establish whether vertical/transplacental transmission was occurring in this population of Leishmania-infected US dogs and determine the effect that this means of transmission has on immune recognition of Leishmania. A pregnant L. infantum-infected dam donated to Iowa State University gave birth in-house to 12 pups. Eight pups humanely euthanized at the time of birth and four pups and the dam humanely euthanized three months post-partum were studied via L. infantum-kinetoplast specific quantitative PCR (kqPCR), gross and histopathological assessment and CD4+ T cell proliferation assay. This novel report describes disseminated L. infantum parasites as identified by kqPCR in 8 day old pups born to a naturally-infected, seropositive U.S. dog with no travel history. This is the first report of vertical transmission of L. infantum in naturally-infected dogs in North America, emphasizing that this novel means of transmission could possibly sustain infection within populations. Evidence that vertical transmission of ZVL may be a driving force for ongoing disease in an otherwise non-endemic region has significant implications on current control strategies for ZVL, as at present parasite elimination efforts in endemic areas are largely focused on vector-borne transmission between canines and people

Transplacental transmission of Leishmania infantum as a means for continued disease incidence in North America.

Directory of Open Access Journals (Sweden)

Paola Mercedes Boggiatto

2011-04-01

Full Text Available Dogs are the predominant domestic reservoir for human L. infantum infection. Zoonotic visceral leishmaniasis (ZVL is an emerging problem in some U.S. dog breeds, with an annual quantitative PCR prevalence of greater than 20% within an at-risk Foxhound population. Although classically Leishmania is transmitted by infected sand flies and phlebotomine sand flies exist in the United States, means of ongoing L. infantum transmission in U.S. dogs is currently unknown. Possibilities include vertical (transplacental/transmammary and horizontal/venereal transmission. Several reports have indicated that endemic ZVL may be transmitted vertically.Our aims for this present study were to establish whether vertical/transplacental transmission was occurring in this population of Leishmania-infected US dogs and determine the effect that this means of transmission has on immune recognition of Leishmania.A pregnant L. infantum-infected dam donated to Iowa State University gave birth in-house to 12 pups. Eight pups humanely euthanized at the time of birth and four pups and the dam humanely euthanized three months post-partum were studied via L. infantum-kinetoplast specific quantitative PCR (kqPCR, gross and histopathological assessment and CD4+ T cell proliferation assay.This novel report describes disseminated L. infantum parasites as identified by kqPCR in 8 day old pups born to a naturally-infected, seropositive U.S. dog with no travel history. This is the first report of vertical transmission of L. infantum in naturally-infected dogs in North America, emphasizing that this novel means of transmission could possibly sustain infection within populations.Evidence that vertical transmission of ZVL may be a driving force for ongoing disease in an otherwise non-endemic region has significant implications on current control strategies for ZVL, as at present parasite elimination efforts in endemic areas are largely focused on vector-borne transmission between canines

Preventing the transmission of mitochondrial DNA disorders using prenatal or preimplantation genetic diagnosis.

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Smeets, Hubert J M; Sallevelt, Suzanne C E H; Dreesen, Jos C F M; de Die-Smulders, Christine E M; de Coo, Irenaeus F M

2015-09-01

Mitochondrial disorders are among the most common inborn errors of metabolism; at least 15% are caused by mitochondrial DNA (mtDNA) mutations, which occur de novo or are maternally inherited. For familial heteroplasmic mtDNA mutations, the mitochondrial bottleneck defines the mtDNA mutation load in offspring, with an often high or unpredictable recurrence risk. Oocyte donation is a safe option to prevent the transmission of mtDNA disease, but the offspring resulting from oocyte donation are genetically related only to the father. Prenatal diagnosis (PND) is technically possible but usually not applicable because of limitations in predicting the phenotype. For de novo mtDNA point mutations, recurrence risks are low and PND can be offered to provide reassurance regarding fetal health. PND is also the best option for female carriers with low-level mutations demonstrating skewing to 0% or 100%. A fairly new option for preventing the transmission of mtDNA diseases is preimplantation genetic diagnosis (PGD), in which embryos with a mutant load below a mutation-specific or general expression threshold of 18% can be transferred. PGD is currently the best reproductive option for familial heteroplasmic mtDNA point mutations. Nuclear genome transfer and genome editing techniques are currently being investigated and might offer additional reproductive options for specific mtDNA disease cases. © 2015 New York Academy of Sciences.

Mother-to-Child HIV-1 Transmission Events Are Differentially Impacted by Breast Milk and Its Components from HIV-1-Infected Women.

Directory of Open Access Journals (Sweden)

Ruizhong Shen

Full Text Available Breast milk is a vehicle of infection and source of protection in post-natal mother-to-child HIV-1 transmission (MTCT. Understanding the mechanism by which breast milk limits vertical transmission will provide critical insight into the design of preventive and therapeutic approaches to interrupt HIV-1 mucosal transmission. However, characterization of the inhibitory activity of breast milk in human intestinal mucosa, the portal of entry in postnatal MTCT, has been constrained by the limited availability of primary mucosal target cells and tissues to recapitulate mucosal transmission ex vivo. Here, we characterized the impact of skimmed breast milk, breast milk antibodies (Igs and non-Ig components from HIV-1-infected Ugandan women on the major events of HIV-1 mucosal transmission using primary human intestinal cells and tissues. HIV-1-specific IgG antibodies and non-Ig components in breast milk inhibited the uptake of Ugandan HIV-1 isolates by primary human intestinal epithelial cells, viral replication in and transport of HIV-1- bearing dendritic cells through the human intestinal mucosa. Breast milk HIV-1-specific IgG and IgA, as well as innate factors, blocked the uptake and transport of HIV-1 through intestinal mucosa. Thus, breast milk components have distinct and complementary effects in reducing HIV-1 uptake, transport through and replication in the intestinal mucosa and, therefore, likely contribute to preventing postnatal HIV-1 transmission. Our data suggests that a successful preventive or therapeutic approach would require multiple immune factors acting at multiple steps in the HIV-1 mucosal transmission process.

Outcomes of prevention of mother to child transmission of the human immunodeficiency virus-1 in rural Kenya--a cohort study.

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Nduati, Eunice Wambui; Hassan, Amin Shaban; Knight, Miguel Garcia; Muema, Daniel Muli; Jahangir, Margaret Nassim; Mwaringa, Shalton Lwambi; Etyang, Timothy Juma; Rowland-Jones, Sarah; Urban, Britta Christina; Berkley, James Alexander

2015-10-03

Success in prevention of mother-to-child transmission (PMTCT) raises the prospect of eliminating pediatric HIV infection. To achieve global elimination, however, strategies are needed to strengthen PMTCT interventions. This study aimed to determine PMTCT outcomes and identify challenges facing its successful implementation in a rural setting in Kenya. A retrospective cohort design was used. Routine demographic and clinical data for infants and mothers enrolling for PMTCT care at a rural hospital in Kenya were analysed. Cox and logistic regression were used to determine factors associated with retention and vertical transmission respectively. Between 2006 and 2012, 1338 infants were enrolled and followed up for PMTCT care with earlier age of enrollment and improved retention observed over time. Mother to child transmission of HIV declined from 19.4 % in 2006 to 8.9 % in 2012 (non-parametric test for trend p = 0.024). From 2009 to 2012, enrolling for care after 6 months of age, adjusted Odds Ratio [aOR]: 23.3 [95 % confidence interval (CI): 8.3-65.4], presence of malnutrition ([aOR]: 2.3 [95 % CI: 1.1-5.2]) and lack of maternal use of highly active antiretroviral therapy (HAART) (aOR: 6.5 [95 % CI: 1.4-29.4]) was associated with increased risk of HIV infection. Infant's older age at enrollment, malnutrition and maternal HAART status, were also associated with drop out from care. Infants who were not actively followed up were more likely to drop out from care (adjusted Hazard Ratio: 6.6 [95 % CI: 2.9-14.6]). We report a temporal increase in the proportion of infants enrolling for PMTCT care before 3 months of age, improved retention in PMTCT and a significant reduction in the proportion of infants enrolled who became HIV-infected, emphasizing the benefits of PMTCT. A simple set of risk factors at enrollment can identify mother-infant pairs most at risk of infection or drop out for targeted intervention.

Assessment of topical microbicides to prevent HIV-1 transmission: concepts, testing, lessons learned.

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Friend, David R; Kiser, Patrick F

2013-09-01

The development of topically applied products capable of preventing vaginal and rectal transmission of HIV-1 has been on-going for nearly 20 years. Despite this, only one clinical trial has demonstrated protection against sexual transmission of HIV-1 in women. This review covers the development of microbicides, also referred to as topical pre-exposure prophylaxis (PrEP), through three stages. The first stage focused on nonspecific agents, including surfactants such as nonoxynol-9 (N-9), to prevent HIV-1 transmission. Unfortunately, N-9 enhanced susceptibility to sexual transmission of HIV-1 when evaluated for efficacy. Soon thereafter, other nonspecific agents (polyanions) were quickly moved into large efficacy trials. Due to a lack of coordination among investigators and funders, a large investment was made in a class of compounds shown ultimately to be ineffective, although poor adherence may have contributed to these findings. The second stage involved the assessment of the antiretroviral drug tenofovir, formulated as a vaginal gel, which was found to be modestly effective in a Phase IIb trial (CAPRISA-004) when dosed in a coitally-dependent manner. In another Phase IIb trial, VOICE (MTN-003), tenofovir gel was found to be ineffective when dosed once-daily in a coitally-independent manner. Based on pharmacokinetic data, it was concluded the participants were poorly adherent to this dosing regimen, leading to a lack of efficacy. Tenofovir gel is currently in a Phase III safety and efficacy trial in South Africa (FACTS-001), using the coitally-dependent dosing regimen employed in CAPRISA-004. We are now in the third stage of microbicide research. The antiretroviral drug dapivirine is currently in two Phase III safety and efficacy studies formulated as a vaginal ring. It is hoped that the once-monthly dosing regimen will lead to higher adherence than found in the VOICE study. It is now clear that product adherence could be the greatest challenge to demonstrating

EFFECT OF HIV PREVENTION AND TREATMENT PROGRAM ON HIV AND HCV TRANSMISSION AND HIV MORTALITY AT AN INDONESIAN NARCOTIC PRISON.

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Nelwan, Erni J; Indrati, Agnes K; Isa, Ahmad; Triani, Nurlita; Alam, Nisaa Nur; Herlan, Maria S; Husen, Wahid; Pohan, Herdiman T; Alisjahbana, Bachti; Meheus, Andre; Van Crevel, Reinout; van der Ven, Andre Jam

2015-09-01

Validated data regarding HIV-transmission in prisons in developing countries is scarce. We examined sexual and injecting drug use behavior and HIV and HCV transmission in an Indonesian narcotic prison during the implementation of an HIV prevention and treatment program during 2004-2007 when the Banceuy Narcotic Prison in Indonesia conducted an HIV transmission prevention program to provide 1) HIV education, 2) voluntary HIV testing and counseling, 3) condom supply, 4) prevention of rape and sexual violence, 5) antiretroviral treatment for HIV-positive prisoners and 6) methadone maintenance treatment. During a first survey that was conducted between 2007 and 2009, new prisoners entered Banceuy Narcotics Prison were voluntary tested for HIV and HCV-infection after written informed consent was obtained. Information regarding sexual and injecting risk behavior and physical status were also recorded at admission to the prison. Participants who tested negative for both HIV and HCV during the first survey were included in a second survey conducted during 2008-2011. During both surveys, data on mortality among HIV-seropositive patients were also recorded. All HIV-seropositive participants receive treatment for HIV. HIV/ AIDS-related deaths decreased: 43% in 2006, 18% in 2007, 9% in 2008 and 0% in 2009. No HIV and HCV seroconversion inside Banceuy Narcotic Prison were found after a median of 23 months imprisonment (maximum follow-up: 38 months). Total of 484.8 person-years observation was done. Participants reported HIV transmission risk-behavior in Banceuy Prison during the second survey was low. After implementation of HIV prevention and treatment program, no new HIV or HCV cases were detected and HIV-related mortality decreased.

Historical development of vaginal microbicides to prevent sexual transmission of HIV in women: from past failures to future hopes

Directory of Open Access Journals (Sweden)

Notario-Pérez F

2017-06-01

Full Text Available Fernando Notario-Pérez, Roberto Ruiz-Caro, María-Dolores Veiga-Ochoa Department of Pharmacy and Pharmaceutical Technology, School of Pharmacy, Universidad Complutense de Madrid, Madrid, Spain Abstract: Infection with human immunodeficiency virus (HIV remains a global public health concern and is particularly serious in low- and middle-income countries. Widespread sexual violence and poverty, among other factors, increase the risk of infection in women, while currently available prevention methods are outside the control of most. This has driven the study of vaginal microbicides to prevent sexual transmission of HIV from men to women in recent decades. The first microbicides evaluated were formulated as gels for daily use and contained different substances such as surfactants, acidifiers and monoclonal antibodies, which failed to demonstrate efficacy in clinical trials. A gel containing the reverse transcriptase inhibitor tenofovir showed protective efficacy in women. However, the lack of adherence by patients led to the search for dosage forms capable of releasing the active principle for longer periods, and hence to the emergence of the vaginal ring loaded with dapivirine, which requires a monthly application and is able to reduce the sexual transmission of HIV. The future of vaginal microbicides will feature the use of alternative dosage forms, nanosystems for drug release and probiotics, which have emerged as potential microbicides but are still in the early stages of development. Protecting women with vaginal microbicide formulations would, therefore, be a valuable tool for avoiding sexual transmission of HIV. Keywords: vaginal formulations, microbicides, prevention, sexual transmission, acquired immunodeficiency syndrome (AIDS, human immunodeficiency virus (HIV

Genetic Variability of Bovine Viral Diarrhea Virus and Evidence for a Possible Genetic Bottleneck during Vertical Transmission in Persistently Infected Cattle.

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Natalie Dow

Full Text Available Bovine viral diarrhea virus (BVDV, a Pestivirus in the family Flaviviridae, is an economically important pathogen of cattle worldwide. The primary propagators of the virus are immunotolerant persistently infected (PI cattle, which shed large quantities of virus throughout life. Despite the absence of an acquired immunity against BVDV in these PI cattle there are strong indications of viral variability that are of clinical and epidemiological importance. In this study the variability of E2 and NS5B sequences in multiple body compartments of PI cattle were characterized using clonal sequencing. Phylogenetic analyses revealed that BVDV exists as a quasispecies within PI cattle. Viral variants were clustered by tissue compartment significantly more often than expected by chance alone with the central nervous system appearing to be a particularly important viral reservoir. We also found strong indications for a genetic bottleneck during vertical transmission from PI animals to their offspring. These quasispecies analyses within PI cattle exemplify the role of the PI host in viral propagation and highlight the complex dynamics of BVDV pathogenesis, transmission and evolution.

Barriers and facilitating factors to the uptake of antiretroviral drugs for prevention of mother-to-child transmission of HIV in sub-Saharan Africa: a systematic review

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Gourlay, Annabelle; Birdthistle, Isolde; Mburu, Gitau; Iorpenda, Kate; Wringe, Alison

2013-01-01

Objectives To investigate and synthesize reasons for low access, initiation and adherence to antiretroviral drugs by mothers and exposed babies for prevention of mother-to-child transmission (PMTCT) of HIV in sub-Saharan Africa. Methods A systematic literature review was conducted. Four databases were searched (Medline, Embase, Global Health and Web of Science) for studies conducted in sub-Saharan Africa from January 2000 to September 2012. Quantitative and qualitative studies were included that met pre-defined criteria. Antiretroviral (ARV) prophylaxis (maternal/infant) and combination antiretroviral therapy (ART) usage/registration at HIV care and treatment during pregnancy were included as outcomes. Results Of 574 references identified, 40 met the inclusion criteria. Four references were added after searching reference lists of included articles. Twenty studies were quantitative, 16 were qualitative and eight were mixed methods. Forty-one studies were conducted in Southern and East Africa, two in West Africa, none in Central Africa and one was multi-regional. The majority (n=25) were conducted before combination ART for PMTCT was emphasized in 2006. At the individual-level, poor knowledge of HIV/ART/vertical transmission, lower maternal educational level and psychological issues following HIV diagnosis were the key barriers identified. Stigma and fear of status disclosure to partners, family or community members (community-level factors) were the most frequently cited barriers overall and across time. The extent of partner/community support was another major factor impeding or facilitating the uptake of PMTCT ARVs, while cultural traditions including preferences for traditional healers and birth attendants were also common. Key health-systems issues included poor staff-client interactions, staff shortages, service accessibility and non-facility deliveries. Conclusions Long-standing health-systems issues (such as staffing and service accessibility) and community

Prevention of Congenital Transmission of Malaria in Sub-Saharan African Countries: Challenges and Implications for Health System Strengthening

OpenAIRE

Osungbade, Kayode O.; Oladunjoye, Olubunmi O.

2012-01-01

Objectives. Review of burden of congenital transmission of malaria, challenges of preventive measures, and implications for health system strengthening in sub-Saharan Africa. Methods. Literature from Pubmed (MEDLINE), Biomed central, Google Scholar, and Cochrane Database were reviewed. Results. The prevalence of congenital malaria in sub-Saharan Africa ranges from 0 to 23%. Diagnosis and existing preventive measures are constantly hindered by weak health systems and sociocultural issues. WHO ...

Dynamic investigation of a locomotive with effect of gear transmissions under tractive conditions

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Chen, Zaigang; Zhai, Wanming; Wang, Kaiyun

2017-11-01

Locomotive is used to drag trailers to move or supply the braking forces to slow the running speed of a train. The electromagnetic torque of the motor is always transmitted by the gear transmission system to the wheelset for generation of the tractive or braking forces at the wheel-rail contact interface. Consequently, gear transmission system is significant for power delivery of a locomotive. This paper develops a comprehensive locomotive-track vertical-longitudinal coupled dynamics model with dynamic effect of gear transmissions. This dynamics model enables considering the coupling interactions between the gear transmission motion, the vertical and the longitudinal motions of the vehicle, and the vertical vibration of the track structure. In this study, some complicated dynamic excitations, such as the gear time-varying mesh stiffness, nonlinear gear tooth backlash, the nonlinear wheel-rail normal contact force and creep force, and the rail vertical geometrical irregularity, are considered. Then, the dynamic responses of the locomotive under the tractive conditions are demonstrated by numerical simulations based on the established dynamics model and by experimental test. The developed dynamics model is validated by the good agreement between the experimental and the theoretical results. The calculated results reveal that the gear transmission system has strong dynamic interactions with the wheel-rail contact interface including both the vertical and the longitudinal motions, and it has negligible effect on the vibrations of the bogie frame and carbody.

Thermal conductivity of vertically aligned carbon nanotube arrays: Growth conditions and tube inhomogeneity

Energy Technology Data Exchange (ETDEWEB)

Bauer, Matthew L.; Pham, Quang N.; Saltonstall, Christopher B.; Norris, Pamela M. [Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904-4746 (United States)

2014-10-13

The thermal conductivity of vertically aligned carbon nanotube arrays (VACNTAs) grown on silicon dioxide substrates via chemical vapor deposition is measured using a 3ω technique. For each sample, the VACNTA layer and substrate are pressed to a heating line at varying pressures to extract the sample's thermophysical properties. The nanotubes' structure is observed via transmission electron microscopy and Raman spectroscopy. The presence of hydrogen and water vapor in the fabrication process is tuned to observe the effect on measured thermal properties. The presence of iron catalyst particles within the individual nanotubes prevents the array from achieving the overall thermal conductivity anticipated based on reported measurements of individual nanotubes and the packing density.

A Survey of Knowledge, Attitude, and Practice of AIDS Patients with Regard to the Prevention of Disease Transmission in Yazd and Ahvaz, Iran

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Mohammad Hosein Baghianimoghadam

2016-12-01

Full Text Available Introduction The aim of this study was to determine the knowledge, attitude, and practice of AIDS patients with regard to the prevention of disease transmission in Yazd and Ahvaz, Iran. Methods In this cross-sectional study, we evaluated the knowledge, attitude, and practice of 130 patients, selected via simple sampling, with regard to the prevention of disease transmission in Yazd and Ahvaz, Iran (65 cases from each city. Data were collected by researchers, using a questionnaire and a checklist. For statistical analysis, descriptive and analytical tests were performed, using SPSS version 16. Results In this study, the sample included 130 AIDS patients from Yazd and Ahvaz. Overall, 67.6% of the patients were male; on the other hand, 29.2% and 32.3% of the participants from Yazd and Ahvaz were female, respectively. As the findings revealed, 44.6% and 55.4% of the patients from Yazd and Ahvaz were married, respectively. The mean scores of knowledge, attitude, and practice of the patients regarding the prevention of HIV transmission were 40.31 ± 3.3, 41.92 ± 8.8, and 43.28 ± 5.3 in Yazd, respectively. Also, the mean scores of knowledge, attitude, and practice with regard to the prevention of HIV transmission were 40.68 ± 3.2.5, 42.52 ± 9.05, and 43.24 ± 6.08 among patients from Ahvaz, respectively. Overall, the results showed that the knowledge, attitude, and practice of most patients were at a medium level. Also, most of the participants from Yazd (70.8% and Ahvaz (56.9% had obtained information at AIDS counseling centers. Conclusions The results highlighted the need to educate patients regarding the prevention of HIV transmission.

Low pH immobilizes and kills human leukocytes and prevents transmission of cell-associated HIV in a mouse model

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Markham Richard B

2005-09-01

Full Text Available Abstract Background Both cell-associated and cell-free HIV virions are present in semen and cervical secretions of HIV-infected individuals. Thus, topical microbicides may need to inactivate both cell-associated and cell-free HIV to prevent sexual transmission of HIV/AIDS. To determine if the mild acidity of the healthy vagina and acid buffering microbicides would prevent transmission by HIV-infected leukocytes, we measured the effect of pH on leukocyte motility, viability and intracellular pH and tested the ability of an acidic buffering microbicide (BufferGel® to prevent the transmission of cell-associated HIV in a HuPBL-SCID mouse model. Methods Human lymphocyte, monocyte, and macrophage motilities were measured as a function of time and pH using various acidifying agents. Lymphocyte and macrophage motilities were measured using video microscopy. Monocyte motility was measured using video microscopy and chemotactic chambers. Peripheral blood mononuclear cell (PBMC viability and intracellular pH were determined as a function of time and pH using fluorescent dyes. HuPBL-SCID mice were pretreated with BufferGel, saline, or a control gel and challenged with HIV-1-infected human PBMCs. Results Progressive motility was completely abolished in all cell types between pH 5.5 and 6.0. Concomitantly, at and below pH 5.5, the intracellular pH of PBMCs dropped precipitously to match the extracellular medium and did not recover. After acidification with hydrochloric acid to pH 4.5 for 60 min, although completely immotile, 58% of PBMCs excluded ethidium homodimer-1 (dead-cell dye. In contrast, when acidified to this pH with BufferGel, a microbicide designed to maintain vaginal acidity in the presence of semen, only 4% excluded dye at 10 min and none excluded dye after 30 min. BufferGel significantly reduced transmission of HIV-1 in HuPBL-SCID mice (1 of 12 infected compared to saline (12 of 12 infected and a control gel (5 of 7 infected. Conclusion These

Planning for pre-exposure prophylaxis to prevent HIV transmission: challenges and opportunities

Science.gov (United States)

2010-01-01

There are currently several ongoing or planned trials evaluating the efficacy of pre-exposure prophylaxis (PrEP) as a preventative approach to reducing the transmission of HIV. PrEP may prove ineffective, demonstrate partial efficacy, or show high efficacy and have the potential to reduce HIV infection in a significant way. However, in addition to the trial results, it is important that issues related to delivery, implementation and further research are also discussed. As a part of the ongoing discussion, in June 2009, the Bill & Melinda Gates Foundation sponsored a Planning for PrEP conference with stakeholders to review expected trial results, outline responsible educational approaches, and develop potential delivery and implementation strategies. The conference reinforced the need for continued and sustained dialogue to identify where PrEP implementation may fit best within an integrated HIV prevention package. This paper identifies the key action points that emerged from the Planning for PrEP meeting. PMID:20624303

Description of an oral Chagas disease outbreak in Venezuela, including a vertically transmitted case.

Science.gov (United States)

Noya, Belkisyolé Alarcón de; Pérez-Chacón, Gladymar; Díaz-Bello, Zoraida; Dickson, Sonia; Muñoz-Calderón, Arturo; Hernández, Carlos; Pérez, Yadira; Mauriello, Luciano; Moronta, Eyleen

2017-08-01

We describe the eleventh major outbreak of foodborne Trypanosoma cruzi transmission in urban Venezuela, including evidence for vertical transmission from the index case to her fetus. After confirming fetal death at 24 weeks of gestation, pregnancy interruption was performed. On direct examination of the amniotic fluid, trypomastigotes were detected. T. cruzi specific-polymerase chain reaction (PCR) also proved positive when examining autopsied fetal organs. Finally, microscopic fetal heart examination revealed amastigote nests. Acute orally transmitted Chagas disease can be life threatening or even fatal for pregnant women and unborn fetuses owing to vertical transmission. There is therefore an urgent need to improve national epidemiologic control measures.

Effectiveness of ART and condom use for prevention of sexual HIV transmission in serodiscordant couples: a systematic review and meta-analysis.

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Huixin Liu

Full Text Available BACKGROUND: Consistent and correct condom use and suppressive antiretroviral therapy for the infected partner are two of the primary strategies recommended for prevention of heterosexual HIV transmission in serodiscordant couples today. The applied effectiveness of treatment as a prevention strategy in China is still under investigation, and much less is known about its effects in the presence of other prevention strategies such as consistent condom use. METHODS: We conducted a systematic search in PubMed and three Chinese language databases to identify relevant articles for the estimation of relative effectiveness of a consistent condom use and b ART use by index partners for preventing HIV transmission in serodiscordant couples. We also estimated the prevention effectiveness of ART stratified by condom use level and the prevention effectiveness of consistent condom use stratified by ART use level. RESULTS: Pooled results from the eleven eligible studies found a pooled HIV seroconversion incidence of 0.92 cases per 100 person years (PY among HIV-negative spouses whose index partners were taking ART versus 2.45 cases per 100 PY in untreated couples. The IRR comparing seroconversion in couples where the index-partner was on ART versus not on ART was 0.47 (95%CI: 0.43, 0.52, while stratified by condom use, the IRR was 0.33(0.17,0.64. The IRR comparing incidence in couples reporting "consistent condom use" versus those reporting otherwise was 0.02(95%CI:0.01,0.04, after stratified by ART use level, the IRR was 0.01(95%CI: 0.00, 0.06. CONCLUSIONS: ART use by index partners could reduce HIV transmission in serodiscordant couples, and the effectiveness of this prevention strategy could be further increased with consistent condom use.

Spatiotemporal dynamics of HIV-1 transmission in France (1999-2014) and impact of targeted prevention strategies.

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Chaillon, Antoine; Essat, Asma; Frange, Pierre; Smith, Davey M; Delaugerre, Constance; Barin, Francis; Ghosn, Jade; Pialoux, Gilles; Robineau, Olivier; Rouzioux, Christine; Goujard, Cécile; Meyer, Laurence; Chaix, Marie-Laure

2017-02-21

Characterizing HIV-1 transmission networks can be important in understanding the evolutionary patterns and geospatial spread of the epidemic. We reconstructed the broad molecular epidemiology of HIV from individuals with primary HIV-1 infection (PHI) enrolled in France in the ANRS PRIMO C06 cohort over 15 years. Sociodemographic, geographic, clinical, biological and pol sequence data from 1356 patients were collected between 1999 and 2014. Network analysis was performed to infer genetic relationships, i.e. clusters of transmission, between HIV-1 sequences. Bayesian coalescent-based methods were used to examine the temporal and spatial dynamics of identified clusters from different regions in France. We also evaluated the use of network information to target prevention efforts. Participants were mostly Caucasian (85.9%) and men (86.7%) who reported sex with men (MSM, 71.4%). Overall, 387 individuals (28.5%) were involved in clusters: 156 patients (11.5%) in 78 dyads and 231 participants (17%) in 42 larger clusters (median size: 4, range 3-41). Compared to individuals with single PHI (n = 969), those in clusters were more frequently men (95.9 vs 83%, p turnaround time for sample processing, targeting prevention efforts based on phylogenetic monitoring may be an efficient way to deliver prevention interventions but would require near real time targeted interventions on the identified index cases and their partners.

Price formation and transmission along the food commodity chain

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Ivana Blažková

2012-01-01

Full Text Available The article is focused on analysis of price transmission along the wheat commodity chain in the Czech Republic, with the distinction on wheat products with low value added (wheat flour, respectively high value added (wheat rolls. The degree of vertical price transmission is measured to identify potential market failures, because asymmetric price transmission can be the result of existence of market power within the food commodity chain. The data basis is made up from monthly prices on partial markets of the analyzed commodity chain published by Czech Statistical Office and Ministry of Agriculture of the Czech Republic. The monitored time period is from January 2000 till October 2009. The analysis is based on calculation of the price transmission elasticity coefficient (evaluation of price transmission along the chain and the intensity of dependency of positive and negative inter-market price differences (evaluation whether positive or negative price changes are better transmitted among particular vertical markets. Time lag is tested as well. The assessment of price transmission along the wheat commodity chain confirmed the existence of market power especially on the retail stage and low impact of price changes of farm prices on final consumer food prices.

The Effects of Peer Education on The Behaviors Regarding HIV/AIDS Transmission Prevention Among Street Children in Bandung City

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Lia Meilianingsih

2017-07-01

Full Text Available All adolescents are vulnerable to HIV/AIDS, including street children. The behaviors of street children are much influenced by their peers. Peer education can enhance knowledge, attitudes, beliefs, and skills and empower children to be responsible for protecting the health of themselves and their peers (Wahyuni, 2012. This study aims to determine the effects of peer health education on the HIV/AIDS Preventive Behaviors of Street Children in Bandung City in 2015. The research employed a quasi-experimental method with the pre-post-test control group design. The sample was 26 people for the treatment group and 26 people for the control group, respectively, taken with purposive sampling technique. Interventions began with peer educator training and then the peer educators provided health education on HIV/AIDS transmission prevention through small group discussions for 2 days. The data in this study were not normally distributed. The paired or dependent data were analyzed using the Wilcoxon test, while the unpaired or independent data using Mann-Whitney test. The results of the research show that peer health education had effects on the knowledge and attitudes of the street children (p values 0.00 and 0.00, respectively; however, there was no effect of peer health education on the actions regarding HIV/AIDS transmission prevention among the street children (p value 0.09. Hence, it is advisable to conduct health promotion with peer health education method in an effort of increasing knowledge and attitudes regarding HIV/AIDS transmission prevention among street children that is sustainable and integrated with the existing programs at puskesmas (Community Health Center.

Experimental study of fire barriers preventing vertical fire spread in ETISs

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Xin Huang

2013-11-01

Full Text Available In recent years, the external thermal insulation system (ETIS has been applied increasingly in a large amount of buildings for energy conservation purpose. However, the increase use of combustible insulation materials in the ETIS has raised serious fire safety problems. Fires involving this type of ETIS have caused severe damage and loss. In order to improve its fire safety, fire barriers were suggested to be installed. This paper introduces fire experiments that have been done to study the effects of fire barriers on preventing vertical fire spread along the ETIS. The experiments were performed according to BS 8414-1:2002 “Fire performance of external cladding systems – Part 1: Test method for non-loadbearing external cladding systems applied to the face of the building”. The test facility consists of a 9 m high wall. The fire sources were wood cribs with a fire size of 3 ± 0.5 MW. The insulation materials were expanded polystyrene foam (EPS. The fire barrier was a horizontal strip of rockwool with a width of 300 mm. Thermocouples were used to measure temperatures outside and inside the ETIS. A series of experiments with different fire scenarios were done: no fire barrier, two fire barriers and three fire barriers at different heights. Test results were compared. The results show that the ETIS using EPS without fire barriers almost burned out, while the ETIS with fire barriers performed well in preventing fire spread. The temperatures above the fire barrier were much lower than those below the fire barrier, and most of the insulation materials above the top fire barrier stayed in place.

Eliminating Perinatal HIV Transmission

Centers for Disease Control (CDC) Podcasts

2012-11-26

In this podcast, CDC’s Dr. Steve Nesheim discusses perinatal HIV transmission, including the importance of preventing HIV among women, preconception care, and timely HIV testing of the mother. Dr. Nesheim also introduces the revised curriculum Eliminating Perinatal HIV Transmission intended for faculty of OB/GYN and pediatric residents and nurse midwifery students.  Created: 11/26/2012 by Division of HIV/AIDS Prevention.   Date Released: 11/26/2012.

Strategies to prevent HIV transmission among heterosexual African-American women

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Peters Ronald J

2005-03-01

Full Text Available Abstract Background African-American women are disproportionately affected by HIV, accounting for 60% of all cases among women in the United States. Although their race is not a precursor for HIV, the socioeconomic and cultural disparities associated with being African American may increase their risk of infection. Prior research has shown that interventions designed to reduce HIV infection among African-American women must address the life demands and social problems they encounter. The present study used a qualitative exploratory design to elicit information about strategies to prevent HIV transmission among young, low-income African-American women. Methods Twenty five low income African American women, ages 18–29, participated in five focus groups of five women each conducted at a housing project in Houston, Texas, a large demographically diverse metropolitan area that is regarded as one of the HIV/AIDS epicenters in the United States. Each group was audiotaped, transcribed, and analyzed using theme and domain analysis. Results The participants revealed that they had most frequently placed themselves at risk for HIV infection through drugs and drinking and they also reported drug and alcohol use as important barriers to practicing safer sex. The women also reported that the need for money and having sex for money to buy food or drugs had placed them at risk for HIV transmission. About one-third of the participants stated that a barrier to their practicing safe sex was their belief that there was no risk based on their being in a monogamous relationship and feeling no need to use protection, but later learning that their mate was unfaithful. Other reasons given were lack of concern, being unprepared, partner's refusal to use a condom, and lack of money to buy condoms. Finally, the women stated that they were motivated to practice safe sex because of fear of contracting sexually transmitted diseases and HIV, desire not to become pregnant, and

HIV pre-exposure prophylaxis for women and infants prevents vaginal and oral HIV transmission in a preclinical model of HIV infection.

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Kovarova, Martina; Shanmugasundaram, Uma; Baker, Caroline E; Spagnuolo, Rae Ann; De, Chandrav; Nixon, Christopher C; Wahl, Angela; Garcia, J Victor

2016-11-01

Approximately 1.5 million HIV-positive women become pregnant annually. Without treatment, up to 45% will transmit HIV to their infants, primarily through breastfeeding. These numbers highlight that HIV acquisition is a major health concern for women and children globally. They also emphasize the urgent need for novel approaches to prevent HIV acquisition that are safe, effective and convenient to use by women and children in places where they are most needed. 4'-Ethynyl-2-fluoro-2'-deoxyadenosine, a potent NRTI with low cytotoxicity, was administered orally to NOD/SCID/γc -/- mice and to bone marrow/liver/thymus (BLT) humanized mice, a preclinical model of HIV infection. HIV inhibitory activity in serum, cervicovaginal secretions and saliva was evaluated 4 h after administration. 4'-Ethynyl-2-fluoro-2'-deoxyadenosine's ability to prevent vaginal and oral HIV transmission was evaluated using highly relevant transmitted/founder viruses in BLT mice. Strong HIV inhibitory activity in serum, cervicovaginal secretions and saliva obtained from animals after a single oral dose of 4'-ethynyl-2-fluoro-2'-deoxyadenosine (10 mg/kg) demonstrated efficient drug penetration into relevant mucosal sites. A single daily oral dose of 4'-ethynyl-2-fluoro-2'-deoxyadenosine resulted in efficient prevention of vaginal and oral HIV transmission after multiple high-dose exposures to transmitted/founder viruses in BLT humanized mice. Our data demonstrated that 4'-ethynyl-2-fluoro-2'-deoxyadenosine efficiently prevents both vaginal and oral HIV transmission. Together with 4'-ethynyl-2-fluoro-2'-deoxyadenosine's relatively low toxicity and high potency against drug-resistant HIV strains, these data support further clinical development of 4'-ethynyl-2-fluoro-2'-deoxyadenosine as a potential pre-exposure prophylaxis agent to prevent HIV transmission in women and their infants. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial

Methicillin-resistant Staphylococcus aureus transmission

DEFF Research Database (Denmark)

Andersen, Leif Percival; Nielsen, Xiaohui

2015-01-01

INTRODUCTION: Even though methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of nosocomial infections, it may often be difficult to evaluate the exact route of transmission. METHODS: In this study, we describe four cases of nosocomial transmission of MRSA in a hospital with a low...... increase the risk of contaminating hands, arms and the front of the uniform. Hand hygiene is therefore essential, but the use of protection gowns with long sleeves is also important in order to prevent transmission of MRSA. After culture of MRSA and implementation of specific precautions to prevent...

Vertical Integration: Teachers' Knowledge and Teachers' Voice.

Science.gov (United States)

Corrie, L.

1995-01-01

Traces the theoretical basis for vertical integration in early school years. Contrasts transmission-based pedagogy with a higher level of teacher control, and acquirer-based pedagogy with a higher level of student control. Suggests that early childhood pedagogy will be maintained when teachers are able to articulate their pedagogical knowledge and…

Almost there: transmission routes of bacterial symbionts between trophic levels.

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Elad Chiel

Full Text Available Many intracellular microbial symbionts of arthropods are strictly vertically transmitted and manipulate their host's reproduction in ways that enhance their own transmission. Rare horizontal transmission events are nonetheless necessary for symbiont spread to novel host lineages. Horizontal transmission has been mostly inferred from phylogenetic studies but the mechanisms of spread are still largely a mystery. Here, we investigated transmission of two distantly related bacterial symbionts--Rickettsia and Hamiltonella--from their host, the sweet potato whitefly, Bemisia tabaci, to three species of whitefly parasitoids: Eretmocerus emiratus, Eretmocerus eremicus and Encarsia pergandiella. We also examined the potential for vertical transmission of these whitefly symbionts between parasitoid generations. Using florescence in situ hybridization (FISH and transmission electron microscopy we found that Rickettsia invades Eretmocerus larvae during development in a Rickettsia-infected host, persists in adults and in females, reaches the ovaries. However, Rickettsia does not appear to penetrate the oocytes, but instead is localized in the follicular epithelial cells only. Consequently, Rickettsia is not vertically transmitted in Eretmocerus wasps, a result supported by diagnostic polymerase chain reaction (PCR. In contrast, Rickettsia proved to be merely transient in the digestive tract of Encarsia and was excreted with the meconia before wasp pupation. Adults of all three parasitoid species frequently acquired Rickettsia via contact with infected whiteflies, most likely by feeding on the host hemolymph (host feeding, but the rate of infection declined sharply within a few days of wasps being removed from infected whiteflies. In contrast with Rickettsia, Hamiltonella did not establish in any of the parasitoids tested, and none of the parasitoids acquired Hamiltonella by host feeding. This study demonstrates potential routes and barriers to horizontal

Factors affecting adherence to short-course ARV prophylaxis for preventing mother-to-child transmission of HIV in sub-Saharan Africa: a review and lessons for future elimination.

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Colombini, Manuela; Stöckl, Heidi; Watts, Charlotte; Zimmerman, Cathy; Agamasu, Enyonam; Mayhew, Susannah H

2014-01-01

Despite the biomedical potential to eliminate vertical HIV transmission, drug adherence to short regimens is often sub-optimal. To inform future programmes, we reviewed evidence on the factors influencing maternal and infant drug adherence to preventing MTCT drug regimens at delivery in sub-Saharan Africa. A literature review yielding 14 studies on adherence to drug regimes among HIV-positive pregnant women and mothers in sub-Saharan Africa was conducted. Rates of maternal adherence to preventive drug regimens at time of delivery varied widely across sites between 35 and 93.5%. Factors most commonly associated with low adherence to antiretroviral therapy (ARV) prophylaxis for preventing MTCT at the health system level include giving birth at home, quality and timing of HIV testing and counselling, and late distribution of nevirapine (NVP). Socio-demographic and demand-side factors include fear of stigma, lack of male involvement, fear of partner's reaction to disclosure, few antenatal (ANC) visits, young age and lack of education. With the implementation of the newly published WHO guidelines recommending triple-drug ARV regimen during pregnancy and breastfeeding for all women with HIV, it is important that women are able to adhere to recommended drug regimens. Service improvements should include clear and timely communication with women about the benefits of combined regimens and greater emphasis on patient confidentiality. Efforts must be made to help women overcome barriers that reduce adherence, such as financial logistical challenges, social stigma and women's fear of violence.

Prevention of mother-to-child transmission of human immunodeficiency virus among pregnant women using injecting drugs in Ukraine, 2000–10

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Thorne, Claire; Semenenko, Igor; Malyuta, Ruslan

2012-01-01

Aims To compare clinical status, mother-to-child transmission (MTCT) rates, use of prevention of (PMTCT) interventions and pregnancy outcomes between HIV-infected injecting drug users (IDUs) and non-IDUs. Design and setting Prospective cohort study conducted in seven human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) Centres in Ukraine, 2000–10. Participants Pregnant HIV-infected women, identified before/during pregnancy or intrapartum, and their live-born infants (n = 6200); 1028 women followed post-partum. Measurements Maternal and delivery characteristics, PMTCT prophylaxis, MTCT rates, preterm delivery (PTD) and low birth weight (LBW). Findings Of 6200 women, 1111 (18%) reported current/previous IDU. The proportion of IDUs diagnosed with HIV before conception increased from 31% in 2000/01 to 60% in 2008/09 (P Ukraine have worse clinical status, poorer access to prevention of mother-to-child transmission prophylaxis and highly active antiretroviral therapy, more adverse pregnancy outcomes and higher risk of mother-to-child transmission than non-injecting drug user women. PMID:21819473

Dengue knowledge in indoor dengue patients from low socioeconomic class; etiology, symptoms, mode of transmission and prevention

International Nuclear Information System (INIS)

Shams, N.; Ahmed, W.; Seetlani, N.K.; Farhat, S.

2018-01-01

Dengue fever has emerged as an emerging public health issue during last decade bearing significant morbidity and economic burden particularly in third world countries. Current study aims to assess various domains of knowledge of indoor dengue patients. Methods: This descriptive cross-sectional study was conducted at Medicine dept. Rawal Institute of Health Sciences Islamabad and BBH Rawalpindi over 6 months. One hundred and twenty-five adult indoor confirmed cases of dengue from lower socioeconomic class were included after ethical approval. The 25-item dengue knowledge questionnaire including aetiology, symptoms, modes of transmission and prevention of dengue was filled. Results: Among 125 cases (77% males and 23% females), mean age was 30+-13 years. Mean knowledge score was 11+-5 points; with excellent knowledge in 6%, good knowledge (22%), moderate knowledge (23%), fair knowledge (34%) and poor knowledge (17%). Mosquito being a vector of dengue was identified by 78%, with peak time in afternoon (48%). Symptoms identified include fever (95%), headache (55%), muscle pain (44%), rash (33%), retro-orbital pain (32%), joint pains (28%) and abdominal pain (18%). Flies and ticks aren't the vectors of dengue according to 61% and 74% respectively, special mosquito is vector (54%), i.e., Aedes Aegypti (18%) that breeds in standing water (53%). Preventive measures identified were netting (56%), insecticide sprays (54%), covering water containers (38%), removing standing water (36%), mosquito repellents (17%), cutting down bushes (22%) and pouring chemicals in standing water (18%). Conclusion: Our patients from lower socioeconomic class, though aware of vector and mode of transmission, have insufficient knowledge of prevention and vector control measures. There is need to strengthen dengue awareness through community based programs, social media, schools and health care centres for high risk people well before the expected epidemic season about mode of transmission

Efficacy of malaria prevention during pregnancy in an area of low and unstable transmission

DEFF Research Database (Denmark)

Ndyomugyenyi, Richard; Clarke, Siân E; Hutchison, Coll L.

2011-01-01

-randomised placebo-controlled trial involving 5775 women of all parities examined the effect of IPTp, ITNs alone, or ITNs used in combination with IPTp on maternal anaemia and low birth weight (LBW) in a highland area of southwestern Uganda. The overall prevalence of malaria infection, maternal anaemia and LBW...... services was observed. With ITNs offering a number of advantages over IPTp, yet showing comparable efficacy, we discuss why ITNs could be an appropriate preventive strategy for malaria control during pregnancy in areas of low and unstable transmission....

Possible non-sexual modes of transmission of human papilloma virus.

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Sabeena, Sasidharanpillai; Bhat, Parvati; Kamath, Veena; Arunkumar, Govindakarnavar

2017-03-01

There is strong evidence to suggest vertical and horizontal modes of transmission of human papilloma virus (HPV), an established etiologic agent of cervical cancer. Infants, children, and adults can acquire both high-risk and low-risk infections by birth or by close contact even though HPV is mainly transmitted sexually. A thorough review of the literature was performed to assess the possible non-sexual modes of transmission of HPV. An electronic search of databases for review articles, cross-sectional studies, cohort studies, and case reports on non-sexual modes of transmission among sexually unexposed women and children was carried out using search terms such as "human papilloma virus, HPV, transmission, horizontal transmission, vertical transmission, and fomites". Articles published between 1983 and 2015 were retrieved. Epidemiological and clinical data support various non-sexual modes of transmission especially at the time of birth and by close contact. Even though the role of fomites in the transmission of HPV is not well established, HPV-DNA positivity has been reported in transvaginal ultrasound probes and colposcopes after routine disinfection. Awareness needs to be spread among the public about alternate modes of transmission. For a proper understanding of the exact natural history of HPV infection acquired via the non-sexual route, long-term prospective studies need to be undertaken. © 2017 Japan Society of Obstetrics and Gynecology.

Vertical Transmission of Hypopituitarism: Critical Importance of Appropriate Interpretation of Thyroid Function Tests and Levothyroxine Therapy During Pregnancy

Science.gov (United States)

Romero, Christopher J.; Radovick, Sally

2013-01-01

Background Typically, newborns with congenital hypothyroidism are asymptomatic at birth, having been exposed to euthyroid mothers. However, hypopituitarism may be associated with central hypothyroidism, preserved fertility, and autosomal dominant inheritance, requiring increased attention to thyroid management during pregnancy. Patient Findings A woman with a history of growth hormone deficiency and central hypothyroidism gave birth to a term male neonate appropriate for gestational age. Due to low thyrotropin (TSH) in the second trimester, the levothyroxine dose was decreased by the obstetrician, and free T4 was low throughout the latter half of pregnancy. The neonatal laboratory evaluation showed central hypothyroidism with a low T4 of 2.1 μg/dL (4.5–11.5) and an inappropriately normal TSH of 0.98 uIU/mL (0.5–4.5); undetectable growth hormone, IGF-I, and IGFBP3; a normal cortisol level; and a normal gonadotropin surge. After initiation of levothyroxine in the first week, both tone and feeding tolerance improved. However, the patient was found to have hearing loss, gross motor delay, and speech delay. Summary In this report, we review a case of vertical transmission of a dominant negative POU1F1 mutation in which fetal abnormalities due to the hypothyroxinemic state during gestation may have been exacerbated by a decrease in the mother's levothyroxine dose based on a low TSH in early gestation. Both mother and fetus were unable to synthesize sufficient thyroid hormone, which may be responsible for the patient's clinical presentation. Conclusion This case underscores several important points in the management of women with hypopituitarism. First, it is important that patients and clinicians are both aware of the differences in etiology, as well as appropriate screening and treatment, of primary versus central hypothyroidism. Second, it is necessary to monitor the thyroid hormone status closely during pregnancy to prevent fetal sequelae of maternal

4 Gbps Impulse Radio (IR) Ultra-Wideband (UWB) Transmission over 100 Meters Multi Mode Fiber with 4 Meters Wireless Transmission

DEFF Research Database (Denmark)

Jensen, Jesper Bevensee; Rodes Lopez, Roberto; Caballero Jambrina, Antonio

2009-01-01

We present experimental demonstrations of in-building impulse radio (IR) ultra-wideband (UWB) link consisting of 100 m multi mode fiber (MMF) and 4 m wireless transmission at a record 4 Gbps, and a record 8 m wireless transmission at 2.5 Gbps. A directly modulated vertical cavity surface emitting...... laser (VCSEL) was used for the generation of the optical signal. 8 m at 2.5 Gbps corresponds to a bit rate - distance product of 20; the highest yet reported for wireless IR-UWB transmission...

Infection control strategies for preventing the transmission of meticillin-resistant Staphylococcus aureus (MRSA) in nursing homes for older people.

Science.gov (United States)

Hughes, Carmel; Tunney, Michael; Bradley, Marie C

2013-11-19

Nursing homes for older people provide an environment likely to promote the acquisition and spread of meticillin-resistant Staphylococcus aureus (MRSA), putting residents at increased risk of colonisation and infection. It is recognised that infection prevention and control strategies are important in preventing and controlling MRSA transmission. To determine the effects of infection prevention and control strategies for preventing the transmission of MRSA in nursing homes for older people. In August 2013, for this third update, we searched the Cochrane Wounds Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), Database of Abstracts of Reviews of Effects (DARE, The Cochrane Library), Ovid MEDLINE, OVID MEDLINE (In-process and Other Non-Indexed Citations), Ovid EMBASE, EBSCO CINAHL, Web of Science and the Health Technology Assessment (HTA) website. Research in progress was sought through Current Clinical Trials, Gateway to Reseach, and HSRProj (Health Services Research Projects in Progress). All randomised and controlled clinical trials, controlled before and after studies and interrupted time series studies of infection prevention and control interventions in nursing homes for older people were eligible for inclusion. Two review authors independently reviewed the results of the searches. Another review author appraised identified papers and undertook data extraction which was checked by a second review author. For this third update only one study was identified, therefore it was not possible to undertake a meta-analysis. A cluster randomised controlled trial in 32 nursing homes evaluated the effect of an infection control education and training programme on MRSA prevalence. The primary outcome was MRSA prevalence in residents and staff, and a change in infection control audit scores which measured adherence to infection control standards. At the end of the 12 month study, there was no change in MRSA

Nanoformulations of Rilpivirine for Topical Pericoital and Systemic Coitus-Independent Administration Efficiently Prevent HIV Transmission

Science.gov (United States)

Date, Abhijit A.; Long, Julie M.; Nochii, Tomonori; Belshan, Michael; Shibata, Annemarie; Vincent, Heather; Baker, Caroline E.; Thayer, William O.; Kraus, Guenter; Lachaud-Durand, Sophie; Williams, Peter; Destache, Christopher J.; Garcia, J. Victor

2015-01-01

Vaginal HIV transmission accounts for the majority of new infections worldwide. Currently, multiple efforts to prevent HIV transmission are based on pre-exposure prophylaxis with various antiretroviral drugs. Here, we describe two novel nanoformulations of the reverse transcriptase inhibitor rilpivirine for pericoital and coitus-independent HIV prevention. Topically applied rilpivirine, encapsulated in PLGA nanoparticles, was delivered in a thermosensitive gel, which becomes solid at body temperature. PLGA nanoparticles with encapsulated rilpivirine coated the reproductive tract and offered significant protection to BLT humanized mice from a vaginal high-dose HIV-1 challenge. A different nanosuspension of crystalline rilpivirine (RPV LA), administered intramuscularly, protected BLT mice from a single vaginal high-dose HIV-1 challenge one week after drug administration. Using transmitted/founder viruses, which were previously shown to establish de novo infection in humans, we demonstrated that RPV LA offers significant protection from two consecutive high-dose HIV-1 challenges one and four weeks after drug administration. In this experiment, we also showed that, in certain cases, even in the presence of drug, HIV infection could occur without overt or detectable systemic replication until levels of drug were reduced. We also showed that infection in the presence of drug can result in acquisition of multiple viruses after subsequent exposures. These observations have important implications for the implementation of long-acting antiretroviral formulations for HIV prevention. They provide first evidence that occult infections can occur, despite the presence of sustained levels of antiretroviral drugs. Together, our results demonstrate that topically- or systemically administered rilpivirine offers significant coitus-dependent or coitus-independent protection from HIV infection. PMID:26271040

Disposable gendine antimicrobial gloves for preventing transmission of pathogens in health care settings.

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Reitzel, Ruth; Rosenblatt, Joel; Jiang, Ying; Hachem, Ray; Raad, Issam

2014-01-01

Transmission of organisms by contact of gloves with surfaces following contact with a pathogen source has been recognized as an important vector for pathogenesis of health care-associated infections. In these cases, the gloves protect the wearer from contact with the pathogenic organisms; however, this personal protection can facilitate the wearer unwittingly becoming a carrier of the pathogens from one location to another. A novel gendine (combination of chlorhexidine and gentian violet) antiseptic coating for the external surface of the glove was developed as a potential intervention to prevent this mode of transmission. We characterized the ability of the coating to rapidly kill bacterial and fungal pathogens within 1 minute of contact with the glove surface. The International Organization of Standardization 22196 concentrated inoculum contact testing methodology was followed. The gendine-coated gloves were able to fully eradicate multidrug-resistant organisms included methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterocci, multidrug-resistant Pseudomonas aeruginosa, and Klebsiella pneumoniae carbapenemase producing. In addition, Candida albicans, Candida glabarata, and 2 pathogenic Escherichia coli strains commonly associated with invasive gastroenteritis were also fully eradicated within 1 minute of contact. The gendine coating did not adversely impact the finish or integrity of the disposable gloves. The highly efficacious gendine-coated antimicrobial gloves potentially provide an additional means of protection against horizontal transmission of common pathogens in a hospital setting. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Galantamine Prevents Long-Lasting Suppression of Excitatory Synaptic Transmission in CA1 Pyramidal Neurons of Soman-Challenged Guinea Pigs

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Alexandrova, E. A.; Alkondon, M.; Aracava, Y.; Pereira, E. F. R.; Albuquerque, E. X.

2014-01-01

Galantamine, a drug currently approved for treatment of Alzheimer's disease, has recently emerged as an effective pretreatment against the acute toxicity and delayed cognitive deficits induced by organophosphorus (OP) nerve agents, including soman. Since cognitive deficits can result from impaired glutamatergic transmission in the hippocampus, the present study was designed to test the hypothesis that hippocampal glutamatergic transmission declines following an acute exposure to soman and that this effect can be prevented by galantamine. To test this hypothesis, spontaneous excitatory postsynaptic currents (EPSCs) were recorded from CA1 pyramidal neurons in hippocampal slices obtained at 1 h, 24 h, or 6-9 days after guinea pigs were injected with: (i) 1xLD50 soman (26.3 μg/kg, s.c.); (ii) galantamine (8 mg/kg, i.m.) followed 30 min later by 1xLD50 soman, (iii) galantamine (8 mg/kg, i.m.), or (iv) saline (0.5 ml/kg, i.m.). In soman-injected guinea pigs that were not pretreated with galantamine, the frequency of EPSCs was significantly lower than that recorded from saline-injected animals. There was no correlation between the severity of soman-induced acute toxicity and the magnitude of soman-induced reduction of EPSC frequency. Pretreatment with galantamine prevented the reduction of EPSC frequency observed at 6-9 days after the soman challenge. Prevention of soman-induced long-lasting reduction of hippocampal glutamatergic synaptic transmission may be an important determinant of the ability of galantamine to counter cognitive deficits that develop long after an acute exposure to the nerve agent. PMID:25064080

Modeling effective transmission pathways and control of the world's most successful parasite.

Science.gov (United States)

Turner, Matthew; Lenhart, Suzanne; Rosenthal, Benjamin; Zhao, Xiaopeng

2013-06-01

Toxoplasma gondii(T. gondii) is a single-celled, intracellular protozoan responsible for the disease toxoplasmosis. The parasite is prevalent worldwide, and it infects all warm-blooded vertebrates. Consumption of meats in which this parasite has encysted confers risk of infection to people and other animals, as does ingestion of water or foods contaminated with environmentally resistant oocysts excreted by cats. Vertical transmission (from mother to offspring) is also possible, leading to disease risk and contributing additional means of ensuring perpetuation of transmission. In this work, we adopt a differential equation model to investigate the effective transmission pathways of T. gondii, as well as potential control mechanisms. Detailed analyses are carried out to examine the significance of transmission routes, virulence, vertical transmission, parasite-induced changes in host behavior, and controls based on vaccination and harvesting. Modeling and analysis efforts may shed insights into understanding the complex life cycle of T. gondii. Copyright © 2013 Elsevier Inc. All rights reserved.

Resultados de la aplicación de tres guías nacionales para prevenir la transmisión vertical del VIH en el Instituto Nacional Materno Perinatal. Lima, Perú Results of the implementation of three national guidelines for the prevention of HIV vertical transmission in instituto Nacional Materno Perinatal. Lima, Perú

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Carlos Velásquez

2011-09-01

Full Text Available Se realiza un análisis retrospectivo de tres periodos sucesivos entre los años 1996 al 2009, para evaluar el impacto de la aplicación de tres guías nacionales para la prevención de la transmisión vertical del VIH. Se incluyeron 275 nacimientos en los 13 años de estudio. Se encontraron diferencias significativas en el porcentaje de casos de VIH entre los niños expuestos al virus en los tres periodos: 15 % durante el periodo en el cual solo se administraba zidovudina (AZT a la gestante; 6,4 % durante el segundo (administración de AZT a la gestante sin criterios de inicios de TARGA, y TARGA a las que tenían criterios para este tratamiento, y 4 % durante el tercer periodo en el cual se aplicó TARGA a todas las gestantes con infección por VIH. El 95 % de las gestantes culminaron el embarazo por cesárea y el 100 % de niños recibió fórmula maternizada. Los cambios realizados en las guías nacionales han producido un impacto favorable en la disminución de nacimientos de niños infectados por el VIH en el Instituto Nacional Materno Perinatal en Perú.A retrospective analysis is performed in three successive periods between the years 1996 and 2009, in order to evaluate the impact of the implementation of three national guidelines for the prevention of the vertical transmission of HIV. 275 births were included in 13 years. Significant statistical differences were found in the percentage of HIV cases in the children exposed to the virus between the three periods: 15% during the period in which only zidovudine (AZT was administered to the pregnant woman, 6.4% during the second period (administration of AZT to the pregnant woman not fulfilling HAART initiation criteria and HAART to those fulfilling criteria for this treatment, and 4% during the third period in which HAART was applied to all pregnant women with HIV infection. 95% of pregnant women ended their pregnancy by cesarean section and the 100% of children received infant formula

Historical development of vaginal microbicides to prevent sexual transmission of HIV in women: from past failures to future hopes.

Science.gov (United States)

Notario-Pérez, Fernando; Ruiz-Caro, Roberto; Veiga-Ochoa, María-Dolores

2017-01-01

Infection with human immunodeficiency virus (HIV) remains a global public health concern and is particularly serious in low- and middle-income countries. Widespread sexual violence and poverty, among other factors, increase the risk of infection in women, while currently available prevention methods are outside the control of most. This has driven the study of vaginal microbicides to prevent sexual transmission of HIV from men to women in recent decades. The first microbicides evaluated were formulated as gels for daily use and contained different substances such as surfactants, acidifiers and monoclonal antibodies, which failed to demonstrate efficacy in clinical trials. A gel containing the reverse transcriptase inhibitor tenofovir showed protective efficacy in women. However, the lack of adherence by patients led to the search for dosage forms capable of releasing the active principle for longer periods, and hence to the emergence of the vaginal ring loaded with dapivirine, which requires a monthly application and is able to reduce the sexual transmission of HIV. The future of vaginal microbicides will feature the use of alternative dosage forms, nanosystems for drug release and probiotics, which have emerged as potential microbicides but are still in the early stages of development. Protecting women with vaginal microbicide formulations would, therefore, be a valuable tool for avoiding sexual transmission of HIV.

Shock to the System: Prevention of Mother-to-Child Transmission of HIV and Child Mortality

OpenAIRE

Nicholas Wilson

2012-01-01

This paper examines the effect of introducing a new HIV/AIDS service, prevention of mother-to-child transmission of HIV (PMTCT), on overall quality of prenatal and postnatal care. My results suggest that local PMTCT introduction in Zambia may have actually increased all cause child mortality in the short term. There is some evidence that vaccinations may have declined in the short term in association with local PMTCT introduction, suggesting that the new service may have partly crowded out ex...

Zoonotic transmission of Chlamydia psittaci in a chicken and turkey hatchery.

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Dickx, Veerle; Vanrompay, Daisy

2011-06-01

Chlamydia psittaci is an obligately intracellular Gram-negative bacterium causing respiratory disease (chlamydiosis) or asymptomatic carriage in birds. C. psittaci is a zoonotic agent causing psittacosis or parrot fever in humans. Vertical and/or horizontal transmission via eggs might have serious repercussions on the C. psittaci infection status of poultry flocks and thus on zoonotic risk for all workers along the poultry supply chain. We therefore studied the presence of C. psittaci in a hatchery. In addition, we examined all (n = 4) employees of the hatchery to evaluate the zoonotic risk. We could not detect C. psittaci on either eggshells or eggshell membranes. However, C. psittaci isolates of different outer-membrane protein A (ompA) genotypes were cultured from the air of both turkey (genotypes A and C) and chicken (genotype D) hatching chambers. Zoonotic transmission occurred in all employees and a mixed infection with up to three different genotypes (A, D and C), also found in air samples, was discovered. Diagnostic monitoring and reporting of C. psittaci infections in poultry workers should be promoted. Additionally, an efficient veterinary vaccine and information campaigns on zoonotic risk and preventive measures against C. psittaci transmission would be beneficial to public health.

Intermittent preventive treatment for the prevention of malaria during pregnancy in high transmission areas

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Massougbodji Achille

2007-12-01

Full Text Available Abstract Malaria in pregnancy is one of the major causes of maternal morbidity and adverse birth outcomes. In high transmission areas, its prevention has recently changed, moving from a weekly or bimonthly chemoprophylaxis to intermittent preventive treatment (IPTp. IPTp consists in the administration of a single curative dose of an efficacious anti-malarial drug at least twice during pregnancy – regardless of whether the woman is infected or not. The drug is administered under supervision during antenatal care visits. Sulphadoxine-pyrimethamine (SP is the drug currently recommended by the WHO. While SP-IPTp seems an adequate strategy, there are many issues still to be explored to optimize it. This paper reviewed data on IPTp efficacy and discussed how to improve it. In particular, the determination of both the optimal number of doses and time of administration of the drug is essential, and this has not yet been done. As both foetal growth and deleterious effects of malaria are maximum in late pregnancy women should particularly be protected during this period. Monitoring of IPTp efficacy should be applied to all women, and not only to primi- and secondigravidae, as it has not been definitively established that multigravidae are not at risk for malaria morbidity and mortality. In HIV-positive women, there is an urgent need for specific information on drug administration patterns (need for higher doses, possible interference with sulpha-based prophylaxis of opportunistic infections. Because of the growing level of resistance of parasites to SP, alternative drugs for IPTp are urgently needed. Mefloquine is presently one of the most attractive options because of its long half life, high efficacy in sub-Saharan Africa and safety during pregnancy. Also, efforts should be made to increase IPTp coverage by improving the practices of health care workers, the motivation of women and their perception of malaria complications in pregnancy. Because IPTp

Control of mother-to-child transmission of infectious diseases in Brazil: progress in HIV/AIDS and failure in congenital syphilis Controle da transmissão vertical de doenças infecciosas no Brasil: avanços na infecção pelo HIV/AIDS e descompasso na sífilis congênita

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Alberto Novaes Ramos Jr.

2007-01-01

Full Text Available In Brazil, syphilis and HIV infection are considered serious public health problems. However, in practice, epidemiological surveillance, prevention measures, and prenatal care seem to be more effective in the control of mother-to-child transmission of the HIV than in the control of transmission of the Treponema pallidum. Here we discuss the differences in surveillance, prenatal care, and care of the newborn. Important differences were identified. It is concluded that there is an urgent need to establish prevention of mother-to-child transmission of syphilis as a public health priority, using an integrated approach including women's health, children's health, primary health care, and STD/AIDS programs on all governmental levels. These issues also need to be discussed with all stakeholders involved. Important aspects related to the problem are the training of public health professionals, as well as the participation of the community. The elimination of congenital syphilis does not require expensive drugs, and diagnostic tools, but a long-term sustainable approach.No Brasil, a infecção pelo Treponema pallidum e pelo vírus da imunodeficiência humana são eventos considerados prioritários. No entanto, apesar das políticas públicas, a resposta em termos das ações de vigilância e prevenção, assistência pré-natal e ao recém-nascido, é diferenciada, parecendo ser mais bem estruturada para a redução da transmissão vertical do HIV do que para a do T. pallidum. No presente artigo, potenciais diferenças são analisadas quanto ao desenvolvimento das ações. Identificou-se que as desigualdades existentes na atenção aos dois problemas apresentam dimensões diferenciadas nas regiões do país. Reconheceu-se a necessária e urgente priorização da sífilis na gravidez, envolvendo áreas técnicas como atenção básica, saúde da mulher, saúde da criança e controle de doenças sexualmente transmissíveis, em todas as esferas de governo

Reticence in disclosure of HIV infection and reasons for bereavement: impact on perinatally infected adolescents' mental health and understanding of HIV treatment and prevention in Johannesburg, South Africa.

Science.gov (United States)

Woollett, Nataly; Black, Vivian; Cluver, Lucie; Brahmbhatt, Heena

2017-07-01

Survival rates of perinatally infected HIV-positive adolescents (PIA) are increasing in sub-Saharan Africa. There is a gap in understanding how disclosure and bereavement have an impact on PIA beliefs and understanding of their HIV infection and its management. In-depth interviews were conducted with 25 purposively selected adolescents aged 13-19 years from 5 public health clinics in Johannesburg, South Africa. Data were analysed using NVivo 10 using a thematic approach. PIA experience incomplete disclosure both of their HIV status and reasons for their bereavements, which limits their understanding of how they became infected, vertical transmission and prevention options like prevention of mother-to-child transmission (PMTCT). Most participants were orphaned and were experiencing complicated grieving (i.e., engaged in unresolved tasks of grieving) which had a negative impact on their mental health, and ability to accept their HIV status and adhere to treatment. PIA need improved communication regarding vertical transmission and how they became HIV-positive, as well as reasons for death of their loved ones to properly understand their HIV status and engage effectively in management. Honest communication about how relatives died and truthful engagement in the process of disclosure of HIV status is necessary to reduce stigma and complicated grieving, and improve mental health in this population.

Ownership unbundling of gas transmission networks. Empirical evidence

Energy Technology Data Exchange (ETDEWEB)

Growitsch, Christian [Koeln Univ. (Germany). Energiewirtschaftliches Inst.; Stronzik, Marcus [Scientific Institute for Infrastructure and Communication Services (WIK), Bad Honnef (Germany)

2011-07-15

The European Commission has intensively discussed the mandatory separation of natural gas transmission from production and services. However, economic theory is ambiguous on the price effects of vertical separation. In this paper, we empirically analyse the effect of ownership unbundling of gas transmission networks as the strongest form of vertical separation on the level of end-user prices. Therefore, we apply different dynamic estimators as system GMM and the bias-corrected least-squares dummy variable or LSDVC estimator on an unbalanced panel out of 18 EU countries over 19 years, allowing us to avoid the endogeneity problem and to estimate the long-run effects of regulation. We introduce a set of regulatory indicators as market entry regulation, ownership structure, vertical separation and market structure and account for structural and economic country specifics. Among these different estimators, we consistently find that ownership unbundling has no impact on natural gas end-user prices, while the more modest legal unbundling reduces them significantly. Furthermore, third-party access, market structure and privatisation show significant influence with the latter leading to higher price levels.

Prevention of parent to child transmission of HIV: Urgent need to be addressed

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Dhrubajyoti J Debnath

2013-01-01

Full Text Available Context: An estimated 430,000 children were newly infected with HIV in 2008, over 90% of them through mother-to-child transmission (MTCT. Without intervention, the risk of MTCT ranges from 20% to 45% as per the World Health Organization (WHO. Aim: To find the uptake of Prevention of Parent to Child Transmission of HIV/AIDS (PPTCT services during pregnancy. Setting and Design: Cross-sectional study. Materials and Methods: Ethical approval and informed consent was taken. Uptake of PPTCT services by the mother was obtained in 222 pregnancies. This was compared with the HIV status of children born to them. Statistical Analysis Used: Percentages. Results: In 25.7% pregnancies, the mothers were tested for HIV. One child was born was to a mother who had tested HIV negative in pregnancy. In 50% of the mother-child pairs, both mother and child received PPTCT. Where both the mother and child received PPTCT, only 13.3% children born were HIV positive as against 40% children who were HIV positive where neither mother nor the child had received PPTCT. Conclusion: Uptake of PPTCT services was low. In countries like India where the chances of parent to child transmission of HIV are likely to be more than in developed countries due to breastfeeding practices, the uptake of PPTCT services should be maximized to decrease the burden of pediatric HIV because even a single pediatric HIV infection counts. All the pregnant women need to be voluntarily tested twice for HIV in pregnancy, in which the second test for HIV may be in late pregnancy.

Investigation into the possibility of vertical transmission of avian bornavirus in free-ranging Canada geese (Branta canadensis).

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Delnatte, Pauline; Nagy, Eva; Ojkic, Davor; Crawshaw, Graham; Smith, Dale A

2014-01-01

To investigate the possibility of in ovo infection with avian bornavirus (ABV) in wild Canada geese (Branta canadensis), 53 eggs were opportunistically collected at various stages of embryonic development from 16 free-ranging goose nests at a large urban zoo site where ABV infection is known to be present in this species. ABV RNA was detected in the yolk of one of three unembryonated eggs using real-time reverse transcription polymerase chain reaction. ABV RNA was not identified in the brains from 23 newly hatched goslings or 19 embryos, nor from three early whole embryos. Antibodies against ABV were not detected in the plasma of any of the hatched goslings using an enzyme-linked immunosorbent assay. Possible reasons for the failure to detect ABV RNA in hatchlings or embryos include low sample size, eggs deriving from parents not actively infected with ABV, the testing of only brain tissue, and failure of the virus to replicate in Canada goose embryos. In conclusion, this preliminary investigation demonstrating the presence of ABV RNA in the yolk of a Canada goose egg provides the first evidence for the potential for vertical transmission of ABV in waterfowl.

Full standard triple wireless transmission over 50m large core diameter graded index POF

NARCIS (Netherlands)

Shi, Y.; Morant, M.; Tangdiongga, E.; Llorente, R.; Koonen, A.M.J.

2011-01-01

We demonstrated for the first time a successful radio-over-1mm core diameter plastic optical fibre transmission of three simultaneous full standard wireless signals. Up to 50-m long transmission distance employing an eye-safe vertical cavity surface emitting laser has been achieved. The transmission

Prevention of sexually transmitted HIV infections through the President's Emergency Plan for AIDS Relief: a history of achievements and lessons learned.

Science.gov (United States)

Ryan, Caroline A; Conly, Shanti R; Stanton, David L; Hasen, Nina S

2012-08-15

HIV prevention in the President's Emergency Plan for AIDS Relief (PEPFAR) began when both data on HIV prevalence and the toolbox of interventions for prevention of sexual transmission were relatively limited. PEPFAR's early focus was on scaling-up information, education, and communication programs that included messaging on abstinence for youth and faithfulness primarily through nongovernmental organizations, including faith-based organizations. Additional activities included condom promotion, distribution, and social marketing. In epidemics concentrated within key populations, PEPFAR's prevention efforts focused on a minimum package of services including outreach, information, education, and communication programs, STI treatment (where appropriate), and condom promotion and distribution. As more epidemiological data became available and with experience gleaned in these early efforts, the need for tailored and flexible approaches became evident. The next iteration of prevention efforts still emphasized behavioral interventions, but incorporated a sharper focus on key epidemic drivers, especially multiple partners; a data-driven emphasis on high transmission areas and populations, including prevention with people living with HIV; and a more strategic and coordinated approach at the national level. Recently, the paradigm for prevention efforts has shifted yet again. Evidence that biomedical interventions such as male circumcision, treatment for prevention of vertical and horizontal transmission, and treatment itself could lead to declines in incidence has refocused PEPFAR's prevention portfolio. New guidance on sexually transmitted HIV focuses on combination prevention, emphasizing biomedical, behavioral and structural approaches. Landmark speeches by the President and the Secretary of State and new ambitious targets for PEPFAR point toward a new goal: an AIDS-free generation.

Role of male partners in the prevention of mother-to-child HIV transmission

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Osoti A

2014-07-01

Full Text Available Alfred Osoti,1–3 Hannah Han,4 John Kinuthia,1,5 Carey Farquhar3,4,6 1Department of Obstetrics and Gynecology, University of Nairobi, Nairobi, Kenya; 2Department of Obstetrics and Gynecology, AIC Kijabe Hospital, Kijabe, Kenya; 3Department of Epidemiology, 4Department of Global Health, University of Washington, Seattle, USA; 5Department of Obstetrics and Gynecology, Kenyatta National Hospital, Nairobi, Kenya; 6Department of Medicine, University of Washington, Seattle, USA Abstract: There is emerging evidence that in resource-limited settings with a high human immunodeficiency virus (HIV burden, male partner involvement in prevention of mother-to-child HIV transmission (PMTCT is associated with improved uptake of effective interventions and infant HIV-free survival. There is also increasing evidence that male partner involvement positively impacts non-HIV related outcomes, such as skilled attendance at delivery, exclusive breastfeeding, uptake of effective contraceptives, and infant immunizations. Despite these associations, male partner involvement remains low, especially when offered in the standard antenatal clinic setting. In this review we explore strategies for improving rates of antenatal male partner HIV testing and argue that the role of male partners in PMTCT must evolve from one of support for HIV-infected pregnant and breastfeeding women to one of comprehensive engagement in prevention of primary HIV acquisition, avoidance of unintended pregnancies, and improved HIV-related care and treatment for the HIV-infected and uninfected women, their partners, and children. Involving men in all components of PMTCT has potential to contribute substantially to achieving virtual elimination of mother-to-child HIV transmission; promoting partner-friendly programs and policies, as well as pursuing research into numerous gaps in knowledge identified in this review, will help drive this process. Keywords: male involvement, limited-resource settings

Infection control strategies for preventing the transmission of meticillin-resistant Staphylococcus aureus (MRSA) in nursing homes for older people.

Science.gov (United States)

Hughes, Carmel; Smith, Michael; Tunney, Michael; Bradley, Marie C

2011-12-07

Nursing homes for older people provide an environment likely to promote the acquisition and spread of meticillin-resistant Staphylococcus aureus (MRSA), putting residents at increased risk of colonisation and infection. It is recognised that infection prevention and control strategies are important in preventing and controlling MRSA transmission. To determine the effects of infection prevention and control strategies for preventing the transmission of MRSA in nursing homes for older people. We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library 2011, Issue 2), the Cochrane Wounds Group Specialised Register (searched May 27th, 2011). We also searched Ovid MEDLINE (from 1950 to April Week 2 2011), OVID MEDLINE (In-process and Other Non-Indexed Citations, April 26th 2011) Ovid EMBASE (1980 to 2011 Week 16), EBSCO CINAHL (1982 to April 21st 2011), DARE (1992 to 2011, week 16), Web of Science (1981 to May 2011), and the Health Technology Assessment (HTA) website (1988 to May 2011). Research in progress was sought through Current Clinical Trials (www.controlled-trials.com), Medical Research Council Research portfolio, and HSRPRoj (current USA projects). All randomised and controlled clinical trials, controlled before and after studies and interrupted time series studies of infection prevention and control interventions in nursing homes for older people were eligible for inclusion. Two review authors independently reviewed the results of the searches. Another review author appraised identified papers and undertook data extraction which was checked by a second review author. For this second update only one study was identified, therefore it was not possible to undertake a meta-analysis. A cluster randomised controlled trial in 32 nursing homes evaluated the effect of an infection control education and training programme on MRSA prevalence. The primary outcome was MRSA prevalence in residents and staff, and a change in infection

Veterans Affairs methicillin-resistant Staphylococcus aureus prevention initiative associated with a sustained reduction in transmissions and health care-associated infections.

Science.gov (United States)

Evans, Martin E; Kralovic, Stephen M; Simbartl, Loretta A; Freyberg, Ron W; Obrosky, D Scott; Roselle, Gary A; Jain, Rajiv

2013-11-01

Implementation of a methicillin-resistant Staphylococcus aureus (MRSA) Prevention Initiative was associated with significant declines in MRSA transmission and MRSA health care-associated infection rates in Veterans Affairs acute care facilities nationwide in the 33-month period from October 2007 through June 2010. Here, we show continuing declines in MRSA transmissions (P = .004 for trend, Poisson regression) and MRSA health care-associated infections (P < .001) from July 2010 through June 2012. The Veterans Affairs Initiative was associated with these effects, sustained over 57 months, in a large national health care system. Published by Mosby, Inc.

Atlas transmission line breakdown analysis

CERN Document Server

Nielsen, K E; Ballard, E O; Elizondo, J M; Gribble, R F; McCuistian, B T; Parsons, W M

1999-01-01

The Atlas facility will use 24 radially converging, vertically oriented and tapered, oil insulated, triplate transmission lines between the Marx generators and the central load region. Among the requirements of the transmission lines are low inductance and high reliability. The inter-conductor gap is nominally 2 cm and the lines taper from a height of 1.75 m at the Marx end to 0.32 m at the output end. The aluminum conductors, held together by 20 insulating spacers, are assembled and inserted as a unit into radial oil-filled steel tanks. The negative, high-voltage, center conductor is 2.54-cm thick and the outer ground conductors are 1.59-cm thick. All 24 triplate transmission lines connect to a transition section at near 1 m radius that couples the transmission lines to a disk/conical solid- dielectric-insulated power flow channel transmission line terminating at the load. Peak operating voltage on the lines can be as high as 240 kV with an effective stress time of 0.8 mu s. Testing of small sections of the ...

Evaluating the cost-effectiveness of combination antiretroviral therapy for the prevention of mother-to-child transmission of HIV in Uganda

NARCIS (Netherlands)

Kuznik, Andreas; Lamorde, Mohammed; Hermans, Sabine; Castelnuovo, Barbara; Auerbach, Brandon; Semeere, Aggrey; Sempa, Joseph; Ssennono, Mark; Ssewankambo, Fred; Manabe, Yukari C.

2012-01-01

Objective To model the cost-effectiveness in Uganda of combination antiretroviral therapy (ART) to prevent mother-to-child transmission of human immunodeficiency virus (HIV). Methods The cost-effectiveness of ART was evaluated on the assumption that ART reduces the risk of an HIV-positive pregnant

High-Speed Semiconductor Vertical-Cavity Surface-Emitting Lasers for Optical Data-Transmission Systems (Review)

Science.gov (United States)

Blokhin, S. A.; Maleev, N. A.; Bobrov, M. A.; Kuzmenkov, A. G.; Sakharov, A. V.; Ustinov, V. M.

2018-01-01

The main problems of providing a high-speed operation semiconductor lasers with a vertical microcavity (so-called "vertical-cavity surface-emitting lasers") under amplitude modulation and ways to solve them have been considered. The influence of the internal properties of the radiating active region and the electrical parasitic elements of the equivalent circuit of lasers are discussed. An overview of approaches that lead to an increase of the cutoff parasitic frequency, an increase of the differential gain of the active region, the possibility of the management of mode emission composition and the lifetime of photons in the optical microcavities, and reduction of the influence of thermal effects have been presented. The achieved level of modulation bandwidth of ˜30 GHz is close to the maximum achievable for the classical scheme of the direct-current modulation, which makes it necessary to use a multilevel modulation format to further increase the information capacity of optical channels constructed on the basis of vertical-cavity surface-emitting lasers.

Francisella tularensis: No Evidence for Transovarial Transmission in the Tularemia Tick Vectors Dermacentor reticulatus and Ixodes ricinus

Science.gov (United States)

Genchi, Marco; Prati, Paola; Vicari, Nadia; Manfredini, Andrea; Sacchi, Luciano; Clementi, Emanuela; Bandi, Claudio; Epis, Sara; Fabbi, Massimo

2015-01-01

Background Tularemia is a zoonosis caused by the Francisella tularensis, a highly infectious Gram-negative coccobacillus. Due to easy dissemination, multiple routes of infection, high environmental contamination and morbidity and mortality rates, Francisella is considered a potential bioterrorism threat and classified as a category A select agent by the CDC. Tick bites are among the most prevalent modes of transmission, and ticks have been indicated as a possible reservoir, although their reservoir competence has yet to be defined. Tick-borne transmission of F. tularensis was recognized in 1923, and transstadial transmission has been demonstrated in several tick species. Studies on transovarial transmission, however, have reported conflicting results. Objective The aim of this study was to evaluate the role of ticks as reservoirs for Francisella, assessing the transovarial transmission of F. tularensis subsp. holarctica in ticks, using experimentally-infected females of Dermacentor reticulatus and Ixodes ricinus. Results Transmission electron microscopy and fluorescence in situ hybridization showed F. tularensis within oocytes. However, cultures and bioassays of eggs and larvae were negative; in addition, microscopy techniques revealed bacterial degeneration/death in the oocytes. Conclusions These results suggest that bacterial death might occur in oocytes, preventing the transovarial transmission of Francisella. We can speculate that Francisella does not have a defined reservoir, but that rather various biological niches (e.g. ticks, rodents), that allow the bacterium to persist in the environment. Our results, suggesting that ticks are not competent for the bacterium vertical transmission, are congruent with this view. PMID:26244842

Francisella tularensis: No Evidence for Transovarial Transmission in the Tularemia Tick Vectors Dermacentor reticulatus and Ixodes ricinus.

Directory of Open Access Journals (Sweden)

Marco Genchi

Full Text Available Tularemia is a zoonosis caused by the Francisella tularensis, a highly infectious Gram-negative coccobacillus. Due to easy dissemination, multiple routes of infection, high environmental contamination and morbidity and mortality rates, Francisella is considered a potential bioterrorism threat and classified as a category A select agent by the CDC. Tick bites are among the most prevalent modes of transmission, and ticks have been indicated as a possible reservoir, although their reservoir competence has yet to be defined. Tick-borne transmission of F. tularensis was recognized in 1923, and transstadial transmission has been demonstrated in several tick species. Studies on transovarial transmission, however, have reported conflicting results.The aim of this study was to evaluate the role of ticks as reservoirs for Francisella, assessing the transovarial transmission of F. tularensis subsp. holarctica in ticks, using experimentally-infected females of Dermacentor reticulatus and Ixodes ricinus.Transmission electron microscopy and fluorescence in situ hybridization showed F. tularensis within oocytes. However, cultures and bioassays of eggs and larvae were negative; in addition, microscopy techniques revealed bacterial degeneration/death in the oocytes.These results suggest that bacterial death might occur in oocytes, preventing the transovarial transmission of Francisella. We can speculate that Francisella does not have a defined reservoir, but that rather various biological niches (e.g. ticks, rodents, that allow the bacterium to persist in the environment. Our results, suggesting that ticks are not competent for the bacterium vertical transmission, are congruent with this view.

Mother to offspring transmission of chronic wasting disease in reeves' muntjac deer.

Directory of Open Access Journals (Sweden)

Amy V Nalls

Full Text Available The horizontal transmission of prion diseases has been well characterized in bovine spongiform encephalopathy (BSE, chronic wasting disease (CWD of deer and elk and scrapie of sheep, and has been regarded as the primary mode of transmission. Few studies have monitored the possibility of vertical transmission occurring within an infected mother during pregnancy. To study the potential for and pathway of vertical transmission of CWD in the native cervid species, we used a small cervid model-the polyestrous breeding, indoor maintainable, Reeves' muntjac deer-and determined that the susceptibility and pathogenesis of CWD in these deer reproduce that in native mule and white-tailed deer. Moreover, we demonstrate here that CWD prions are transmitted from doe to fawn. Maternal CWD infection also appears to result in lower percentage of live birth offspring. In addition, evolving evidence from protein misfolding cyclic amplification (PMCA assays on fetal tissues suggest that covert prion infection occurs in utero. Overall, our findings demonstrate that transmission of prions from mother to offspring can occur, and may be underestimated for all prion diseases.

The evolution of transmission mode

Science.gov (United States)

Forbes, Mark R.; Hauffe, Heidi C.; Kallio, Eva R.; Okamura, Beth; Sait, Steven M.

2017-01-01

This article reviews research on the evolutionary mechanisms leading to different transmission modes. Such modes are often under genetic control of the host or the pathogen, and often in conflict with each other via trade-offs. Transmission modes may vary among pathogen strains and among host populations. Evolutionary changes in transmission mode have been inferred through experimental and phylogenetic studies, including changes in transmission associated with host shifts and with evolution of the unusually complex life cycles of many parasites. Understanding the forces that determine the evolution of particular transmission modes presents a fascinating medley of problems for which there is a lack of good data and often a lack of conceptual understanding or appropriate methodologies. Our best information comes from studies that have been focused on the vertical versus horizontal transmission dichotomy. With other kinds of transitions, theoretical approaches combining epidemiology and population genetics are providing guidelines for determining when and how rapidly new transmission modes may evolve, but these are still in need of empirical investigation and application to particular cases. Obtaining such knowledge is a matter of urgency in relation to extant disease threats. This article is part of the themed issue ‘Opening the black box: re-examining the ecology and evolution of parasite transmission’. PMID:28289251

[Preventive measures for avoiding transmission of microorganisms between hospitalised patients. Hand hygiene].

Science.gov (United States)

Lupión, Carmen; López-Cortés, Luis Eduardo; Rodríguez-Baño, Jesús

2014-11-01

Health-care associated infections are an important public health problem worldwide. The rates of health-care associated infections are indicators of the quality of health care. The infection control activities related to prevention of transmission of hospital microorganisms can be grouped in 4 mayor areas: standard precautions, specific precautions (including isolation if appropriate), environmental cleaning and disinfection, and surveillance activities (including providing infection rates and monitoring procedures). Hand hygiene and the correct use of gloves are the most important measures to prevent health-care associated infections and to avoid the dissemination of multidrug-resistant microorganisms. Continuous educational activities aimed at improving adherence to hand hygiene are needed. Periodical assessment of adherence to hand hygiene recommendations with feed-back have been shown to provide sustained improvement. Several complementary activities are being evaluated, including skin decolonization prior to certain surgeries, a package of measures in patients with central venous catheters or mechanical ventilation, and universal body hygiene with chlorhexidine. The present area of discussion concerns in which situations and in which groups would such measures be effective and efficient. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Eliminating Perinatal HIV Transmission

Centers for Disease Control (CDC) Podcasts

In this podcast, CDC’s Dr. Steve Nesheim discusses perinatal HIV transmission, including the importance of preventing HIV among women, preconception care, and timely HIV testing of the mother. Dr. Nesheim also introduces the revised curriculum Eliminating Perinatal HIV Transmission intended for faculty of OB/GYN and pediatric residents and nurse midwifery students.

Co-infecting Reptarenaviruses Can Be Vertically Transmitted in Boa Constrictor.

Directory of Open Access Journals (Sweden)

Saskia Keller

2017-01-01

Full Text Available Boid inclusion body disease (BIBD is an often fatal disease affecting mainly constrictor snakes. BIBD has been associated with infection, and more recently with coinfection, by various reptarenavirus species (family Arenaviridae. Thus far BIBD has only been reported in captive snakes, and neither the incubation period nor the route of transmission are known. Herein we provide strong evidence that co-infecting reptarenavirus species can be vertically transmitted in Boa constrictor. In total we examined five B. constrictor clutches with offspring ranging in age from embryos over perinatal abortions to juveniles. The mother and/or father of each clutch were initially diagnosed with BIBD and/or reptarenavirus infection by detection of the pathognomonic inclusion bodies (IB and/or reptarenaviral RNA. By applying next-generation sequencing and de novo sequence assembly we determined the "reptarenavirome" of each clutch, yielding several nearly complete L and S segments of multiple reptarenaviruses. We further confirmed vertical transmission of the co-infecting reptarenaviruses by species-specific RT-PCR from samples of parental animals and offspring. Curiously, not all offspring obtained the full parental "reptarenavirome". We extended our findings by an in vitro approach; cell cultures derived from embryonal samples rapidly developed IB and promoted replication of some or all parental viruses. In the tissues of embryos and perinatal abortions, viral antigen was sometimes detected, but IB were consistently seen only in the juvenile snakes from the age of 2 mo onwards. In addition to demonstrating vertical transmission of multiple species, our results also indicate that reptarenavirus infection induces BIBD over time in the offspring.

Our views on transmission policy

International Nuclear Information System (INIS)

Wellford, W.H.; Sutley, N.H.

1990-01-01

In this article the authors discuss the need for predictable and fair access to transmission facilities in order to ensure competitive generation of power. They propose that the Federal Energy Regulatory Commission should regulate transmission to prevent a utility from gaining a competitive advantage in electricity generation markets, the incorporation of transmission access into every bidding program under state jurisdiction, and requirement of transmission rates, terms and conditions for all in-state utilities be included in the request for proposal

Creation of a high yielding recombinant maize hybrid for the production of a microbicide for the prevention of HIV-1 transmission

CSIR Research Space (South Africa)

Barros, E

2010-06-01

Full Text Available The aim of this study was to use conventional breeding to increase the production in maize of the human monoclonal antibody 2G12, known to have potential therapeutic properties in the prevention of HIV-1 transmission. The recombinant antibody...

Larvivorous fish for preventing malaria transmission

Science.gov (United States)

Walshe, Deirdre P; Garner, Paul; Adeel, Ahmed A; Pyke, Graham H; Burkot, Thomas R

2017-01-01

-target species. Fish that feed on mosquito larvae for preventing malaria transmission What is the aim of this review? Adult female Anopheles mosquitoes transmit the Plasmodium parasites that cause malaria. The aim of this Cochrane Review was to evaluate whether introducing fish that eat mosquito larvae and pupae (early life stages of mosquitoes) into water sources near where people live will decrease the adult Anopheles mosquito population and thus the number of people infected with Plasmodium parasites. Key messages We do not know if introducing fish that eat mosquito larvae and pupae has an impact on the number of people with malaria or on the adult Anopheles mosquito population. What was studied in the review? The review authors examined the available research that evaluated introducing fish that eat larvae ('larvivorous') to Anopheles mosquito larval habitats in areas where malaria was common. Fifteen small studies looked at the effects of larvivorous fish on Anopheles larvae and pupae in different larval habitats, including localized water bodies (such as wells, domestic water containers, fishponds, and pools; seven studies), riverbed pools below dams (two studies), rice field plots (four studies), and water canals (two studies). These studies were undertaken in Sri Lanka (two studies), India (three studies), Ethiopia (one study), Kenya (two studies), Sudan (one study), Grande Comore Island (one study), Korea (two studies), Indonesia (one study), and Tajikistan (two studies). This is an update of a 2013 Cochrane Review and includes some older unpublished studies from Tajikistan and a new trial from India. What are the main results of the review? In our main analysis, we found no studies that looked at the effects of larvivorous fish on adult Anopheles mosquito populations or on the number of people infected with Plasmodium parasites. In our analysis exploring the effect of fish introduction on the number of Anopheles larvae and pupae in water collections, these studies

Executive summary of the Consensus Statement on monitoring HIV: pregnancy, birth, and prevention of mother-to-child transmission.

Science.gov (United States)

Polo Rodríguez, Rosa; Muñoz Galligo, Eloy; Iribarren, José Antonio; Domingo Pedrol, Pere; Leyes García, María; Maiques Montesinos, Vicente; Miralles Martín, Pilar; Noguera Julian, Antoni; Ocampo Hernandez, Antonio; Peres Bares, María Lourdes; López Rojano, Marta; Suy Franch, Anna; Viñuela Beneitez, M Carmen; González Tomé, María Isabel

2014-05-01

The main objective in the management of HIV-infected pregnant women is prevention of mother-to-child transmission; therefore, it is essential to provide universal antiretroviral treatment, regardless of CD4 count. All pregnant women must receive adequate information and undergo HIV serology testing at the first visit. If the serological status is unknown at the time of delivery, or in the immediate postpartum, HIV serology testing has to be performed as soon as possible. In this document, recommendations are made regarding the health of the mother and from the perspective of minimizing mother-to-child transmission. Copyright © 2013 Elsevier España, S.L. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Influence of Chitosan Swelling Behaviour on Controlled Release of Tenofovir from Mucoadhesive Vaginal Systems for Prevention of Sexual Transmission of HIV

Science.gov (United States)

Notario-Pérez, Fernando; Martín-Illana, Araceli; Cazorla-Luna, Raúl; Ruiz-Caro, Roberto; Bedoya, Luis-Miguel; Tamayo, Aitana; Rubio, Juan; Veiga, María-Dolores

2017-01-01

The main challenges facing efforts to prevent the transmission of human immunodeficiency virus (HIV) are the lack of access to sexual education services and sexual violence against young women and girls. Vaginal formulations for the prevention of sexually transmitted infections are currently gaining importance in drug development. Vaginal mucoadhesive tablets can be developed by including natural polymers that have good binding capacity with mucosal tissues, such as chitosan or guar gum, semisynthetic polymers such as hydroxypropylmethyl cellulose, or synthetic polymers such as Eudragit® RS. This paper assesses the potential of chitosan for the development of sustained-release vaginal tablets of Tenofovir and compares it with different polymers. The parameters assessed were the permanence time of the bioadhesion—determined ex vivo using bovine vaginal mucosa as substrate—the drug release profiles from the formulation to the medium (simulated vaginal fluid), and swelling profiles in the same medium. Chitosan can be said to allow the manufacture of tablets that remain adhered to the vaginal mucosa and release the drug in a sustained way, with low toxicity and moderate swelling that ensures the comfort of the patient and may be useful for the prevention of sexual transmission of HIV. PMID:28230790

Influence of Chitosan Swelling Behaviour on Controlled Release of Tenofovir from Mucoadhesive Vaginal Systems for Prevention of Sexual Transmission of HIV.

Science.gov (United States)

Notario-Pérez, Fernando; Martín-Illana, Araceli; Cazorla-Luna, Raúl; Ruiz-Caro, Roberto; Bedoya, Luis-Miguel; Tamayo, Aitana; Rubio, Juan; Veiga, María-Dolores

2017-02-21

The main challenges facing efforts to prevent the transmission of human immunodeficiency virus (HIV) are the lack of access to sexual education services and sexual violence against young women and girls. Vaginal formulations for the prevention of sexually transmitted infections are currently gaining importance in drug development. Vaginal mucoadhesive tablets can be developed by including natural polymers that have good binding capacity with mucosal tissues, such as chitosan or guar gum, semisynthetic polymers such as hydroxypropylmethyl cellulose, or synthetic polymers such as Eudragit ® RS. This paper assesses the potential of chitosan for the development of sustained-release vaginal tablets of Tenofovir and compares it with different polymers. The parameters assessed were the permanence time of the bioadhesion-determined ex vivo using bovine vaginal mucosa as substrate-the drug release profiles from the formulation to the medium (simulated vaginal fluid), and swelling profiles in the same medium. Chitosan can be said to allow the manufacture of tablets that remain adhered to the vaginal mucosa and release the drug in a sustained way, with low toxicity and moderate swelling that ensures the comfort of the patient and may be useful for the prevention of sexual transmission of HIV.

Coinfection and vertical transmission of Brucella and Morbillivirus in a neonatal sperm whale (Physeter macrocephalus) in Hawaii, USA.

Science.gov (United States)

West, Kristi L; Levine, Gregg; Jacob, Jessica; Jensen, Brenda; Sanchez, Susan; Colegrove, Kathleen; Rotstein, David

2015-01-01

The viral genus Morbillivirus and the bacterial genus Brucella have emerged as important groups of pathogens that are known to affect cetacean health on a global scale, but neither pathogen has previously been reported from endangered sperm whales (Physeter macrocephalus). A female neonate sperm whale stranded alive and died near Laie on the island of Oahu, Hawaii, US, in May of 2011. Congestion of the cerebrum and enlarged lymph nodes were noted on the gross necropsy. Microscopic findings included lymphoid depletion, chronic meningitis, and pneumonia, suggesting an in utero infection. Cerebrum, lung, umbilicus, and select lymph nodes (tracheobronchial and mediastinal) were positive for Brucella by PCR. Brucella sp. was also cultured from the cerebrum and from mediastinal and tracheobronchial lymph nodes. Twelve different tissues were screened for Morbillivirus by reverse-transcriptase (RT)-PCR and select tissues by immunohistochemistry, but only the tracheobronchial lymph node and spleen were positive by RT-PCR. Pathologic findings observed were likely a result of Brucella, but Morbillivirus may have played a key role in immune suppression of the mother and calf. The in utero infection in this individual strongly supports vertical transmission of both pathogens.

Reductions in Transmission Risk Behaviors in HIV-Positive Clients Receiving Prevention Case Management Services: Findings from a Community Demonstration Project

Science.gov (United States)

Gasiorowicz, Mari; Llanas, Michelle R.; DiFranceisco, Wayne; Benotsch, Eric G.; Brondino, Michael J.; Catz, Sheryl L.; Hoxie, Neil J.; Reiser, William J.; Vergeront, James M.

2005-01-01

Prevention case management (PCM) for HIV-infected persons is an HIV risk reduction intervention designed to assist clients who are aware of their HIV infection and who continue to engage in risk transmission behaviors. PCM combines individual risk reduction counseling with case management to address the psychosocial factors affecting HIV…

Model projections on the impact of HCV treatment in the prevention of HCV transmission among people who inject drugs in Europe

DEFF Research Database (Denmark)

Fraser, Hannah; Martin, Natasha K; Brummer-Korvenkontio, Henrikki

2018-01-01

BACKGROUND: Prevention of hepatitis C virus (HCV) transmission among people who inject drugs (PWID) is critical to eliminating HCV in Europe. We estimate impact of current and scaled-up HCV treatment with and without scaling-up opioid substitution therapy (OST) and needle and syringe programmes (...

Creating an African HIV clinical research and prevention trials network: HIV prevalence, incidence and transmission.

Directory of Open Access Journals (Sweden)

Anatoli Kamali

Full Text Available HIV epidemiology informs prevention trial design and program planning. Nine clinical research centers (CRC in sub-Saharan Africa conducted HIV observational epidemiology studies in populations at risk for HIV infection as part of an HIV prevention and vaccine trial network. Annual HIV incidence ranged from below 2% to above 10% and varied by CRC and risk group, with rates above 5% observed in Zambian men in an HIV-discordant relationship, Ugandan men from Lake Victoria fishing communities, men who have sex with men, and several cohorts of women. HIV incidence tended to fall after the first three months in the study and over calendar time. Among suspected transmission pairs, 28% of HIV infections were not from the reported partner. Volunteers with high incidence were successfully identified and enrolled into large scale cohort studies. Over a quarter of new cases in couples acquired infection from persons other than the suspected transmitting partner.

Creating an African HIV Clinical Research and Prevention Trials Network: HIV Prevalence, Incidence and Transmission

Science.gov (United States)

Kamali, Anatoli; Price, Matt A.; Lakhi, Shabir; Karita, Etienne; Inambao, Mubiana; Sanders, Eduard J.; Anzala, Omu; Latka, Mary H.; Bekker, Linda-Gail; Kaleebu, Pontiano; Asiki, Gershim; Ssetaala, Ali; Ruzagira, Eugene; Allen, Susan; Farmer, Paul; Hunter, Eric; Mutua, Gaudensia; Makkan, Heeran; Tichacek, Amanda; Brill, Ilene K.; Fast, Pat; Stevens, Gwynn; Chetty, Paramesh; Amornkul, Pauli N.; Gilmour, Jill

2015-01-01

HIV epidemiology informs prevention trial design and program planning. Nine clinical research centers (CRC) in sub-Saharan Africa conducted HIV observational epidemiology studies in populations at risk for HIV infection as part of an HIV prevention and vaccine trial network. Annual HIV incidence ranged from below 2% to above 10% and varied by CRC and risk group, with rates above 5% observed in Zambian men in an HIV-discordant relationship, Ugandan men from Lake Victoria fishing communities, men who have sex with men, and several cohorts of women. HIV incidence tended to fall after the first three months in the study and over calendar time. Among suspected transmission pairs, 28% of HIV infections were not from the reported partner. Volunteers with high incidence were successfully identified and enrolled into large scale cohort studies. Over a quarter of new cases in couples acquired infection from persons other than the suspected transmitting partner. PMID:25602351

Failure to demonstrate experimental vertical transmission of the epidemic strain of Chikungunya virus in Aedes albopictus from La Réunion Island, Indian Ocean

Directory of Open Access Journals (Sweden)

Marie Vazeille

2009-07-01

Full Text Available Aedes albopictus was responsible for transmission in the first outbreak of chikungunya (CHIK on La Réunion Island, Indian Ocean, in 2005-2006. The magnitude of the outbreak on this island, which had been free of arboviral diseases for over 30 years, as well as the efficiency of Ae. albopictus as the main vector, raises questions about the maintenance of the CHIK virus (CHIKV through vertical transmission mechanisms. Few specimens collected from the field as larvae were found to be infected. In this study, Ae. albopictus originating from La Réunion were orally infected with a blood-meal containing 10(8 pfu/mL of the CHIKV epidemic strain (CHIKV 06.21. Eggs from the first and second gonotrophic cycles were collected and raised to the adult stage. The infectious status of the progeny was checked (i by immunofluorescence on head squashes of individual mosquitoes to detect the presence of viral particles or (ii by quantitative RT-PCR on mosquito pools to detect viral RNA. We analysed a total of 1,675 specimens from the first gonotrophic cycle and 1,709 from the second gonotrophic cycle without detecting any viral particles or viral RNA. These laboratory results are compared to field records.

(Not) getting political: indigenous women and preventing mother-to-child transmission of HIV in West Papua.

Science.gov (United States)

Munro, Jenny; McIntyre, Lynn

2016-01-01

This paper builds on critiques that call for a more nuanced and contextualised understanding of conditions that affect HIV prevention by looking at West Papuan women's experiences of prevention of mother-to-child transmission services. Drawing on qualitative, ethnographic research with indigenous women and health workers, the paper demonstrates that women experience poor-quality HIV education and counselling, and that indigenous practices and concerns are largely not addressed by HIV services. We attribute this to a combination of national anti-indigenous and anti-separatist political concerns with donor-led interventions that result in limited localisation and reduced effectiveness of HIV prevention measures. In West Papua, services are needed that enhance cooperation and shared commitment, and that acknowledge and work to overcome existing inequalities, ethnic tensions and discrimination in the health system. Beyond Indonesia, donor-led HIV programmes and interventions need to balance avoidance of politically sensitive issues with complicity in perpetuating health inequalities. Translating global health interventions and donor priorities into locally compelling HIV prevention activities involves more than navigating local cultural and religious beliefs. Programme development and implementation strategies that entail confronting structural questions as well as social hierarchies, cleavages and silences are needed to render more effective services; strategies that are inherently political.

A systems biology approach to predictive developmental neurotoxicity of a larvicide used in the prevention of Zika virus transmission

DEFF Research Database (Denmark)

Audouze, Karine; Taboureau, Olivier; Grandjean, Philippe

2018-01-01

The need to prevent developmental brain disorders has led to an increased interest in efficient neurotoxicity testing. When an epidemic of microcephaly occurred in Brazil, Zika virus infection was soon identified as the likely culprit. However, the pathogenesis appeared to be complex, and a larvi......The need to prevent developmental brain disorders has led to an increased interest in efficient neurotoxicity testing. When an epidemic of microcephaly occurred in Brazil, Zika virus infection was soon identified as the likely culprit. However, the pathogenesis appeared to be complex...... the potential developmental neurotoxicity, and we applied this method to examine the larvicide pyriproxyfen widely used in the prevention of Zika virus transmission. Our computational model covered a wide range of possible pathways providing mechanistic hypotheses between pyriproxyfen and neurological disorders...

USING TERRESTRIAL LASER SCANNERS TO CALCULATE AND MAP VERTICAL BRIDGE CLEARANCE

OpenAIRE

C. Zhang; D. Arditi; Z. Chen

2013-01-01

The vertical clearance of a bridge over a highway is important in preventing oversized vehicles from hitting the bridge. The vertical clearance of a bridge is traditionally measured by using surveying equipment such as leveling rods and total stations. Typically, measurements are taken at multiple locations in order to determine the minimum vertical clearance under the bridge. This process is time and labor consuming. Also, these measurements may not be accurate because of the traffi...

Review of transmission routes of 24 infectious diseases preventable by biosecurity measures and comparison of the implementation of these measures in pig herds in six European countries

DEFF Research Database (Denmark)

Filippitzi, M. E.; Kruse, Amanda Brinch; Postma, M.

2018-01-01

This study aimed to review the transmission routes of important infectious pig diseases and to translate these into biosecurity measures preventing or reducing the transmission between and within pig herds. Furthermore, it aimed to identify the level of implementation of these measures in different...... European countries and discuss the observed variations to identify potentials for improvement. First, a literature review was performed to show which direct and indirect transmission routes of 24 infectious pig diseases can be prevented through different biosecurity measures. Second, a quantitative...... on biosecurity since 1971 in Denmark. However, the observed pattern may also be attributed to differences in data collection methods. The qualitative analysis identified differences in applied policies, legislation, disease status, pig farm density, farming culture and habits between countries that can be used...

Condoms for sexually transmissible infection prevention: politics versus science.

Science.gov (United States)

Mindel, Adrian; Sawleshwarkar, Shailendra

2008-03-01

The present review assesses the protection that condoms offer against sexually transmissible infections (STI) and the impact that social, political and religious opinion in the USA has had in the past 8 years on promoting condoms for safer sex. Condoms offer protection against most STI. However, the degree of protection depends on correct and consistent use, the type of sexual activity and the biological characteristics of different infections. Cross-sectional and case-control studies and other observational data provide the majority of evidence for STI prevention. Condoms provide a high level of protection against those infections that are transmitted mainly via infected secretions, including HIV, gonorrhoea, chlamydia and trichomoniasis. Protection against those infections transmitted via skin and mucous membrane contact, including Herpes simplex virus infection and human papilloma virus, appears to be less. The Bush administration, driven by conservative political, social and religious elements in the USA, has mounted a concerted campaign to undermine the role of the condom in health-promotion activities in the USA and overseas by undervaluing and misrepresenting scientific data, and through a sustained and well-funded promotion of abstinence-only education. However, this has lead to considerable controversy and disillusionment with abstinence-only education, both at home and abroad, and there is now incontrovertible evidence that abstinence-only programs are ineffectual.

Systematic review of public health research on prevention of mother-to-child transmission of HIV in India with focus on provision and utilization of cascade of PMTCT services

NARCIS (Netherlands)

Darak, Shrinivas; Panditrao, Mayuri; Parchure, Ritu; Kulkarni, Vinay; Kulkarni, Sanjeevani; Janssen, Fanny

2012-01-01

Background: In spite of effective strategies to eliminate mother-to-child-transmission of HIV, the implementation of such strategies remains a major challenge in developing countries. In India, programs for the prevention of mother-to-child transmission (PMTCT) have been scaled up widely since 2005.

Molecular identification of the first local dengue fever outbreak in Shenzhen city, China: a potential imported vertical transmission from Southeast Asia?

Science.gov (United States)

Yang, F; Guo, G Z; Chen, J Q; Ma, H W; Liu, T; Huang, D N; Yao, C H; Zhang, R L; Xue, C F; Zhang, L

2014-02-01

A suspected dengue fever outbreak occurred in 2010 at a solitary construction site in Shenzhen city, China. To investigate this epidemic, we used serological, molecular biological, and bioinformatics techniques. Of nine serum samples from suspected patients, we detected seven positive for dengue virus (DENV) antibodies, eight for DENV-1 RNA, and three containing live viruses. The isolated virus, SZ1029 strain, was sequenced and confirmed as DENV-1, showing the highest E-gene homology to D1/Malaysia/36000/05 and SG(EHI)DED142808 strains recently reported in Southeast Asia. Further phylogenetic tree analysis confirmed their close relationship. At the epidemic site, we also detected 14 asymptomatic co-workers (out of 291) positive for DENV antibody, and DENV-1-positive mosquitoes. Thus, we concluded that DENV-1 caused the first local dengue fever outbreak in Shenzhen. Because no imported case was identified, the molecular fingerprints of the SZ1029 strain suggest this outbreak may be due to vertical transmission imported from Southeast Asia.

Prevention of Mother-to-Child Transmission: Precarious Hopes and Childbearing Choices Among HIV-Infected Women in a Northern Province of Vietnam

DEFF Research Database (Denmark)

Gammeltoft, Tine; Rasch, Vibeke; Bui, Kim Chi

2012-01-01

's faith in their futures and childbearing capacities. Based on the findings, the authors discuss the new forms of gendered uncertainty that arise in the era of HIV/AIDS in Vietnam. They conclude that prevention of mother-to-child transmission, including the counseling offered by health providers, plays...

Tracking transmission of apicomplexan symbionts in diverse Caribbean corals.

Directory of Open Access Journals (Sweden)

Nathan L Kirk

Full Text Available Symbionts in each generation are transmitted to new host individuals either vertically (parent to offspring, horizontally (from exogenous sources, or a combination of both. Scleractinian corals make an excellent study system for understanding patterns of symbiont transmission since they harbor diverse symbionts and possess distinct reproductive modes of either internal brooding or external broadcast spawning that generally correlate with vertical or horizontal transmission, respectively. Here, we focused on the under-recognized, but apparently widespread, coral-associated apicomplexans (Protista: Alveolata to determine if symbiont transmission depends on host reproductive mode. Specifically, a PCR-based assay was utilized towards identifying whether planula larvae and reproductive adults from brooding and broadcast spawning scleractinian coral species in Florida and Belize harbored apicomplexan DNA. Nearly all (85.5%; n = 85/89 examined planulae of five brooding species (Porites astreoides, Agaricia tenuifolia, Agaricia agaricites, Favia fragum, Mycetophyllia ferox and adults of P. astreoides were positive for apicomplexan DNA. In contrast, no (n = 0/10 apicomplexan DNA was detected from planulae of four broadcast spawning species (Acropora cervicornis, Acropora palmata, Pseudodiploria strigosa, and Orbicella faveolata and rarely in gametes (8.9%; n = 5/56 of these species sampled from the same geographical range as the brooding species. In contrast, tissue samples from nearly all (92.0%; n = 81/88 adults of the broadcast spawning species A. cervicornis, A. palmata and O. faveolata harbored apicomplexan DNA, including colonies whose gametes and planulae tested negative for these symbionts. Taken together, these data suggest apicomplexans are transmitted vertically in these brooding scleractinian coral species while the broadcast spawning scleractinian species examined here acquire these symbionts horizontally. Notably, these transmission

Tracking transmission of apicomplexan symbionts in diverse Caribbean corals.

Science.gov (United States)

Kirk, Nathan L; Ritson-Williams, Raphael; Coffroth, Mary Alice; Miller, Margaret W; Fogarty, Nicole D; Santos, Scott R

2013-01-01

Symbionts in each generation are transmitted to new host individuals either vertically (parent to offspring), horizontally (from exogenous sources), or a combination of both. Scleractinian corals make an excellent study system for understanding patterns of symbiont transmission since they harbor diverse symbionts and possess distinct reproductive modes of either internal brooding or external broadcast spawning that generally correlate with vertical or horizontal transmission, respectively. Here, we focused on the under-recognized, but apparently widespread, coral-associated apicomplexans (Protista: Alveolata) to determine if symbiont transmission depends on host reproductive mode. Specifically, a PCR-based assay was utilized towards identifying whether planula larvae and reproductive adults from brooding and broadcast spawning scleractinian coral species in Florida and Belize harbored apicomplexan DNA. Nearly all (85.5%; n = 85/89) examined planulae of five brooding species (Porites astreoides, Agaricia tenuifolia, Agaricia agaricites, Favia fragum, Mycetophyllia ferox) and adults of P. astreoides were positive for apicomplexan DNA. In contrast, no (n = 0/10) apicomplexan DNA was detected from planulae of four broadcast spawning species (Acropora cervicornis, Acropora palmata, Pseudodiploria strigosa, and Orbicella faveolata) and rarely in gametes (8.9%; n = 5/56) of these species sampled from the same geographical range as the brooding species. In contrast, tissue samples from nearly all (92.0%; n = 81/88) adults of the broadcast spawning species A. cervicornis, A. palmata and O. faveolata harbored apicomplexan DNA, including colonies whose gametes and planulae tested negative for these symbionts. Taken together, these data suggest apicomplexans are transmitted vertically in these brooding scleractinian coral species while the broadcast spawning scleractinian species examined here acquire these symbionts horizontally. Notably, these transmission patterns are

Currencies of Mutualisms: Sources of Alkaloid Genes in Vertically Transmitted Epichloae

Directory of Open Access Journals (Sweden)

Christopher L. Schardl

2013-06-01

Full Text Available The epichloae (Epichloë and Neotyphodium species, a monophyletic group of fungi in the family Clavicipitaceae, are systemic symbionts of cool-season grasses (Poaceae subfamily Poöideae. Most epichloae are vertically transmitted in seeds (endophytes, and most produce alkaloids that attack nervous systems of potential herbivores. These protective metabolites include ergot alkaloids and indole-diterpenes (tremorgens, which are active in vertebrate systems, and lolines and peramine, which are more specific against invertebrates. Several Epichloë species have been described which are sexual and capable of horizontal transmission, and most are vertically transmissible also. Asexual epichloae are mainly or exclusively vertically transmitted, and many are interspecific hybrids with genomic contributions from two or three ancestral Epichloë species. Here we employ genome-scale analyses to investigate the origins of biosynthesis gene clusters for ergot alkaloids (EAS, indole-diterpenes (IDT, and lolines (LOL in 12 hybrid species. In each hybrid, the alkaloid-gene and housekeeping-gene relationships were congruent. Interestingly, hybrids frequently had alkaloid clusters that were rare in their sexual ancestors. Also, in those hybrids that had multiple EAS, IDT or LOL clusters, one cluster lacked some genes, usually for late pathway steps. Possible implications of these findings for the alkaloid profiles and endophyte ecology are discussed.

Currencies of Mutualisms: Sources of Alkaloid Genes in Vertically Transmitted Epichloae

Science.gov (United States)

Schardl, Christopher L.; Young, Carolyn A.; Pan, Juan; Florea, Simona; Takach, Johanna E.; Panaccione, Daniel G.; Farman, Mark L.; Webb, Jennifer S.; Jaromczyk, Jolanta; Charlton, Nikki D.; Nagabhyru, Padmaja; Chen, Li; Shi, Chong; Leuchtmann, Adrian

2013-01-01

The epichloae (Epichloë and Neotyphodium species), a monophyletic group of fungi in the family Clavicipitaceae, are systemic symbionts of cool-season grasses (Poaceae subfamily Poöideae). Most epichloae are vertically transmitted in seeds (endophytes), and most produce alkaloids that attack nervous systems of potential herbivores. These protective metabolites include ergot alkaloids and indole-diterpenes (tremorgens), which are active in vertebrate systems, and lolines and peramine, which are more specific against invertebrates. Several Epichloë species have been described which are sexual and capable of horizontal transmission, and most are vertically transmissible also. Asexual epichloae are mainly or exclusively vertically transmitted, and many are interspecific hybrids with genomic contributions from two or three ancestral Epichloë species. Here we employ genome-scale analyses to investigate the origins of biosynthesis gene clusters for ergot alkaloids (EAS), indole-diterpenes (IDT), and lolines (LOL) in 12 hybrid species. In each hybrid, the alkaloid-gene and housekeeping-gene relationships were congruent. Interestingly, hybrids frequently had alkaloid clusters that were rare in their sexual ancestors. Also, in those hybrids that had multiple EAS, IDT or LOL clusters, one cluster lacked some genes, usually for late pathway steps. Possible implications of these findings for the alkaloid profiles and endophyte ecology are discussed. PMID:23744053

Currencies of mutualisms: sources of alkaloid genes in vertically transmitted epichloae.

Science.gov (United States)

Schardl, Christopher L; Young, Carolyn A; Pan, Juan; Florea, Simona; Takach, Johanna E; Panaccione, Daniel G; Farman, Mark L; Webb, Jennifer S; Jaromczyk, Jolanta; Charlton, Nikki D; Nagabhyru, Padmaja; Chen, Li; Shi, Chong; Leuchtmann, Adrian

2013-06-06

The epichloae (Epichloë and Neotyphodium species), a monophyletic group of fungi in the family Clavicipitaceae, are systemic symbionts of cool-season grasses (Poaceae subfamily Poöideae). Most epichloae are vertically transmitted in seeds (endophytes), and most produce alkaloids that attack nervous systems of potential herbivores. These protective metabolites include ergot alkaloids and indole-diterpenes (tremorgens), which are active in vertebrate systems, and lolines and peramine, which are more specific against invertebrates. Several Epichloë species have been described which are sexual and capable of horizontal transmission, and most are vertically transmissible also. Asexual epichloae are mainly or exclusively vertically transmitted, and many are interspecific hybrids with genomic contributions from two or three ancestral Epichloë species. Here we employ genome-scale analyses to investigate the origins of biosynthesis gene clusters for ergot alkaloids (EAS), indole-diterpenes (IDT), and lolines (LOL) in 12 hybrid species. In each hybrid, the alkaloid-gene and housekeeping-gene relationships were congruent. Interestingly, hybrids frequently had alkaloid clusters that were rare in their sexual ancestors. Also, in those hybrids that had multiple EAS, IDT or LOL clusters, one cluster lacked some genes, usually for late pathway steps. Possible implications of these findings for the alkaloid profiles and endophyte ecology are discussed.

Influence of Chitosan Swelling Behaviour on Controlled Release of Tenofovir from Mucoadhesive Vaginal Systems for Prevention of Sexual Transmission of HIV

Directory of Open Access Journals (Sweden)

Fernando Notario-Pérez

2017-02-01

Full Text Available The main challenges facing efforts to prevent the transmission of human immunodeficiency virus (HIV are the lack of access to sexual education services and sexual violence against young women and girls. Vaginal formulations for the prevention of sexually transmitted infections are currently gaining importance in drug development. Vaginal mucoadhesive tablets can be developed by including natural polymers that have good binding capacity with mucosal tissues, such as chitosan or guar gum, semisynthetic polymers such as hydroxypropylmethyl cellulose, or synthetic polymers such as Eudragit® RS. This paper assesses the potential of chitosan for the development of sustained-release vaginal tablets of Tenofovir and compares it with different polymers. The parameters assessed were the permanence time of the bioadhesion—determined ex vivo using bovine vaginal mucosa as substrate—the drug release profiles from the formulation to the medium (simulated vaginal fluid, and swelling profiles in the same medium. Chitosan can be said to allow the manufacture of tablets that remain adhered to the vaginal mucosa and release the drug in a sustained way, with low toxicity and moderate swelling that ensures the comfort of the patient and may be useful for the prevention of sexual transmission of HIV.

Maximal network reliability for a stochastic power transmission network

International Nuclear Information System (INIS)

Lin, Yi-Kuei; Yeh, Cheng-Ta

2011-01-01

Many studies regarded a power transmission network as a binary-state network and constructed it with several arcs and vertices to evaluate network reliability. In practice, the power transmission network should be stochastic because each arc (transmission line) combined with several physical lines is multistate. Network reliability is the probability that the network can transmit d units of electric power from a power plant (source) to a high voltage substation at a specific area (sink). This study focuses on searching for the optimal transmission line assignment to the power transmission network such that network reliability is maximized. A genetic algorithm based method integrating the minimal paths and the Recursive Sum of Disjoint Products is developed to solve this assignment problem. A real power transmission network is adopted to demonstrate the computational efficiency of the proposed method while comparing with the random solution generation approach.

Engineering a segmented dual-reservoir polyurethane intravaginal ring for simultaneous prevention of HIV transmission and unwanted pregnancy.

Directory of Open Access Journals (Sweden)

Justin T Clark

Full Text Available The HIV/AIDS pandemic and its impact on women prompt the investigation of prevention strategies to interrupt sexual transmission of HIV. Long-acting drug delivery systems that simultaneously protect womenfrom sexual transmission of HIV and unwanted pregnancy could be important tools in combating the pandemic. We describe the design, in silico, in vitro and in vivo evaluation of a dual-reservoir intravaginal ring that delivers the HIV-1 reverse transcriptase inhibitor tenofovir and the contraceptive levonorgestrel for 90 days. Two polyether urethanes with two different hard segment volume fractions were used to make coaxial extruded reservoir segments with a 100 µm thick rate controlling membrane and a diameter of 5.5 mm that contain 1.3 wt% levonorgestrel. A new mechanistic diffusion model accurately described the levonorgestrel burst release in early time points and pseudo-steady state behavior at later time points. As previously described, tenofovir was formulated as a glycerol paste and filled into a hydrophilic polyurethane, hollow tube reservoir that was melt-sealed by induction welding. These tenofovir-eluting segments and 2 cm long coaxially extruded levonorgestrel eluting segments were joined by induction welding to form rings that released an average of 7.5 mg tenofovir and 21 µg levonorgestrel per day in vitro for 90 days. Levonorgestrel segments placed intravaginally in rabbits resulted in sustained, dose-dependent levels of levonorgestrel in plasma and cervical tissue for 90 days. Polyurethane caps placed between segments successfully prevented diffusion of levonorgestrel into the tenofovir-releasing segment during storage.Hydrated rings endured between 152 N and 354 N tensile load before failure during uniaxial extension testing. In summary, this system represents a significant advance in vaginal drug delivery technology, and is the first in a new class of long-acting multipurpose prevention drug delivery systems.

Elephant-to-Human Transmission of Tuberculosis

Centers for Disease Control (CDC) Podcasts

This podcast reports on the transmission of TB from elephants to humans. Dr. Rendi Murphree, Epidemic Intelligence Service Officer at the Centers for Disease Control and Prevention and Vanderbilt University Visiting Scholar, discusses the recent elephant-to-human transmission of tuberculosis at an elephant refuge in Tennessee.

Gendered discourses of youth sexualities--an exploration of PubMed articles on prevention of sexually transmissible infections.

Science.gov (United States)

Johansson, Eva E; Alex, Lena; Christianson, Monica

2014-10-01

To explore how gender is addressed in medical articles on the prevention of sexually transmissible infections (STI) among adolescents. Sixtyone articles were retrieved from a PubMed search and scrutinized by qualitative content analysis. Most articles were affiliated with North American research institutions, but there were also reports from Europe, Africa, South America, and Asia. Gender turned up in the following four recurrent discourses: Gendered Receptiveness for Information, Stereotyped Heterosexual Expectations, Power Imbalance in Sexual Relations, and Gendered Prevention Approaches. Young women were described as knowledgeable, communicative, and responsible, but at risk because of feminine ideals and a lack of negotiating power. Men were described as less informed, more reluctant to discuss, and more risk taking due to masculine ideals and power dominance. Prevention approaches concerned how to postpone sex and/or tailor gender-sensitive programs for specific groups of young women and men. Researchers' own gender expectations might have a substantial impact on how sex and sexual health is considered in prevention research. To avoid reconstruction of current inequalities and stereotypes regarding sexual practices of young women and men, the impact of gender, the power structures in intimate relations, and the cultural context should be considered. Medical research on STI prevention could benefit from including a wider array of gender perspectives. Copyright © 2014 Elsevier B.V. All rights reserved.

Analytical computation of reflection and transmission coefficients for love waves

International Nuclear Information System (INIS)

Romanelli, F.; Vaccari, F.

1995-09-01

The computation of the transmission and reflection coefficients is an important step in the construction, if modal summation technique is used, of synthetic seismograms for 2-D or 3-D media. These coupling coefficients for Love waves at a vertical discontinuity are computed analytically. Numerical test for realistic structures show how the energy carried by an incoming mode is redistributed on the various modes existing on both sides of the vertical interface. (author). 15 refs, 8 figs

Blocking effects of human tau on squid giant synapse transmission and its prevention by T-817 MA

Directory of Open Access Journals (Sweden)

Herman eMoreno

2011-05-01

Full Text Available Filamentous tau inclusions are hallmarks of Alzheimer’s disease (AD and related neurodegenerative tauopathies, but the molecular mechanisms involved in tau mediated changes in neuronal function and their possible effects on synaptic transmission are unknown. We have evaluated the effects of human tau protein injected directly into the presynaptic terminal axon of the squid giant synapse, which affords functional, structural, and biochemical analysis of its action on the synaptic release process. Indeed, we have found that at physiological concentrations recombinant human tau isoforms (h-tau 42 become phosphorylated, produce a rapid synaptic transmission block, and induce the formation of clusters of aggregated synaptic vesicles in the vicinity of the active zone. Presynaptic voltage clamp recordings demonstrate that h-tau does not modify the presynaptic calcium current amplitude or kinetics. Analysis of synaptic noise at the post-synaptic axon following pre-synaptic h-tau42 microinjection revealed an initial phase of increase spontaneous transmitter release followed by a marked reduction in noise. Finally, systemic administration of T-817MA, a proposed neuro-protective agent, rescued tau-induced synaptic abnormalities. Our results show novel mechanisms of h-tau42 mediated synaptic transmission failure and more importantly identify a potential therapeutic agent to treat/prevent tau-related neurotoxicity.

Interventions for preventing mother-to-child HIV transmission: protocol of an overview of systematic reviews.

Science.gov (United States)

Wariki, Windy Mariane Virenia; Ota, Erika; Mori, Rintaro; Wiysonge, Charles S; Horvath, Hacsi; Read, Jennifer S

2017-06-21

Various interventions to prevent mother-to-child-transmission (MTCT) of HIV have been investigated and implemented. A number of systematic reviews assessing the efficacy of interventions for the prevention of MTCT of HIV reported antiretroviral prophylaxis, caesarean section before labour and before ruptured membranes, and complete avoidance of breastfeeding were efficacious for preventing MTCT of HIV. Recent WHO guidelines recommend lifelong antiretroviral therapy for all pregnant women for treatment of the woman's own HIV infection and for prevention of MTCT of HIV. Therefore, the objective of this overview is to evaluate the currently available systematic reviews of interventions for preventing MTCT of HIV, and to identify the current best evidence-based interventions for reducing the risk of MTCT of HIV. We will include only peer-reviewed systematic reviews of randomised or quasi-randomised controlled trials assessing the effects of interventions for preventing MTCT of HIV that target both HIV-infected women and children aged 2 years and younger born to HIV-infected women. We will search the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effectiveness, Ovid MEDLINE and EMBASE. We will assess review eligibility, the methodological quality of included systematic reviews using A Measurement Tool to Assess The Systematic Reviews and will extract data, comparing our results and resolving discrepancies by consensus. Finally, we will independently assess the certainty of the evidence using Grades of Recommendation, Assessment, Development and Evaluation. Ethics approval is not required. We will publish the results in a peer-reviewed journal and present at conferences, which will inform future research and will be useful for healthcare managers, administrators and policymakers to guide resource allocation decisions and optimisation of interventions to prevent the MTCT of HIV. © Article author(s) (or their employer(s) unless

Knowledge, Attitudes and Perceptions of Secondary School Teenagers towards HIV Transmission and Prevention in Rural and Urban Areas of Central Uganda.

Science.gov (United States)

Rukundo, Annamaria; Muwonge, Mathias M; Mugisha, Danny; Aturwanaho, Dickens; Kasangaki, Arabat; Bbosa, Godfrey S

2016-01-01

HIV/AIDS has remained a challenge in Uganda among adolescent despite the ABC strategy used globally to prevent HIV infection. The study assessed the knowledge, attitudes and perceptions of secondary school teenagers towards HIV transmission and prevention in rural and urban schools of central Uganda. A cross sectional study using self-administered questionnaires and structured interviews was used to collect data from adolescents in secondary schools in Kampala and Buikwe districts. Eight schools were randomly selected with 4 schools in each district. A total of 245 students from schools were recruited in the study with 120 and 125 students from urban Kampala and rural Buikwe district schools respectively. Data were analyzed using SPSS version 11. The results were expressed as percentages in a 2 × 2 tables. The mean age of the participants was 15.9 ± 2.5 years. Results showed that 95.1% participants had knowledge on HIV/AIDS in both urban and rural schools and 27.4% knew all the modes of HIV transmission. About 83.7% knew the ABC strategy for HIV prevention and 37.6% would talk about HIV/AIDS mainly with friends. For HIV cure, 62.0% of study participants reported non-cure and 24.9% were not sure. The remaining 13.1% of the study participants in both urban and rural schools reported that HIV can be cured. And the modes of curing HIV that were mentioned by participants included spiritual healing, transmitting it to others through sexual intercourse and that antiretroviral (ARVs) drugs can cure it as well as that it can be cured abroad. About 65.7% of participants reported recognition of one with HIV/ AIDS and by having red lips, being sickly; weight loss, skin rash and being very rich were mentioned. About 39.2% of the study participants mentioned that they cannot get infected with HIV and can't contract HIV at all and 18.4% believed that chances of getting HIV infection were high. On perception and attitude on condoms and their use, participants reported that it is

Cost-effectiveness of strategies to prevent methicillin-resistant Staphylococcus aureus transmission and infection in an intensive care unit.

Science.gov (United States)

Gidengil, Courtney A; Gay, Charlene; Huang, Susan S; Platt, Richard; Yokoe, Deborah; Lee, Grace M

2015-01-01

OBJECTIVE To create a national policy model to evaluate the projected cost-effectiveness of multiple hospital-based strategies to prevent methicillin-resistant Staphylococcus aureus (MRSA) transmission and infection. DESIGN Cost-effectiveness analysis using a Markov microsimulation model that simulates the natural history of MRSA acquisition and infection. PATIENTS AND SETTING Hypothetical cohort of 10,000 adult patients admitted to a US intensive care unit. METHODS We compared 7 strategies to standard precautions using a hospital perspective: (1) active surveillance cultures; (2) active surveillance cultures plus selective decolonization; (3) universal contact precautions (UCP); (4) universal chlorhexidine gluconate baths; (5) universal decolonization; (6) UCP + chlorhexidine gluconate baths; and (7) UCP+decolonization. For each strategy, both efficacy and compliance were considered. Outcomes of interest were: (1) MRSA colonization averted; (2) MRSA infection averted; (3) incremental cost per colonization averted; (4) incremental cost per infection averted. RESULTS A total of 1989 cases of colonization and 544 MRSA invasive infections occurred under standard precautions per 10,000 patients. Universal decolonization was the least expensive strategy and was more effective compared with all strategies except UCP+decolonization and UCP+chlorhexidine gluconate. UCP+decolonization was more effective than universal decolonization but would cost $2469 per colonization averted and $9007 per infection averted. If MRSA colonization prevalence decreases from 12% to 5%, active surveillance cultures plus selective decolonization becomes the least expensive strategy. CONCLUSIONS Universal decolonization is cost-saving, preventing 44% of cases of MRSA colonization and 45% of cases of MRSA infection. Our model provides useful guidance for decision makers choosing between multiple available hospital-based strategies to prevent MRSA transmission.

Direct growth of vertically aligned carbon nanotubes on silicon substrate by spray pyrolysis of Glycine max oil

Directory of Open Access Journals (Sweden)

K. T. Karthikeyan

2017-11-01

Full Text Available Vertically aligned carbon nanotubes have been synthesized by spray pyrolysis from Glycine max oil on silicon substrate using ferrocene as catalyst at 650 °C. Glycine max oil, a plant-based hydrocarbon precursor was used as a source of carbon and argon as a carrier gas. The as-grown vertically aligned carbon nanotubes were characterized by scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and Raman spectroscopy. Scanning electron microscopic images reveal that the dense bundles of aligned carbon nanotubes. High resolution transmission electron microscopy and Raman spectroscopy observations indicate that as-grown aligned carbon nanotubes are well graphitized.

Broadcast spawning coral Mussismilia hispida can vertically transfer its associated bacterial core

NARCIS (Netherlands)

Leite, Deborah C. A.; Leao, Pedro; Garrido, Amana G.; Lins, Ulysses; Santos, Henrique F.; Pires, Debora O.; Castro, Clovis B.; van Elsas, Jan D.; Zilberberg, Carla; Rosado, Alexandre S.; Peixoto, Raquel S.

2017-01-01

The hologenome theory of evolution (HTE), which is under fierce debate, presupposes that parts of the microbiome are transmitted from one generation to the next [vertical transmission (VT)], which may also influence the evolution of the holobiont. Even though bacteria have previously been described

Federal travel restrictions to prevent disease transmission in the United States: An analysis of requested travel restrictions.

Science.gov (United States)

Jungerman, M Robynne; Vonnahme, Laura A; Washburn, Faith; Alvarado-Ramy, Francisco

Individuals with certain communicable diseases may pose risks to the health of the traveling public; there has been documented transmission on commercial aircraft of tuberculosis (TB), measles, and severe acute respiratory syndrome (SARS). Federal public health travel restrictions (PHTR) prevent commercial air or international travel of persons with communicable diseases that pose a public health threat. We described demographics and clinical characteristics of all cases considered for PHTR because of suspected or confirmed communicable disease from May 22, 2007, to December 31, 2015. We reviewed 682 requests for PHTR; 414 (61%) actions were completed to place 396 individuals on PHTR. The majority (>99%) had suspected (n = 27) or confirmed (n = 367) infectious pulmonary TB; 58 (16%) had multidrug-resistant-TB. There were 128 (85%) interceptions that prevented the initiation or continuation of travel. PHTR were removed for 310 (78%) individuals after attaining noninfectious status and 86 (22%) remained on PHTR at the end of the analysis period. PHTR effectively prevent exposure during commercial air travel to persons with potentially infectious diseases. In addition, they are effective tools available to public health agencies to prevent commercial travel of individuals with certain communicable diseases and possibly reconnect them with public health authorities. Published by Elsevier Ltd.

New movable plate for efficient millimeter wave vertical on-chip antenna

KAUST Repository

Marnat, Loic; Carreno, Armando Arpys Arevalo; Conchouso Gonzalez, David; Galicia Martinez, Miguel Angel; Foulds, Ian G.; Shamim, Atif

2013-01-01

A new movable plate concept is presented in this paper to realize mm-wave vertical on-chip antennas through MEMS based post-processing steps in a CMOS compatible process. By virtue of its vertical position, the antenna is isolated from the lossy Si substrate and hence performs with a better efficiency as compared to the horizontal position. In addition, the movable plate concept enables polarization diversity by providing both horizontal and vertical polarizations on the same chip. Through a first iteration fractal bowtie antenna design, dual band (60 and 77 GHz) operation is demonstrated in both horizontal and vertical positions without any change in dimensions or use of switches for two different mediums (Si and air). To support the movable plate concept, the transmission line and antenna are designed on a flexible polyamide, where the former has been optimized to operate in the bent position. The design is highly suitable for compact, low cost and efficient SoC solutions. © 1963-2012 IEEE.

New movable plate for efficient millimeter wave vertical on-chip antenna

KAUST Repository

Marnat, Loic

2013-04-01

A new movable plate concept is presented in this paper to realize mm-wave vertical on-chip antennas through MEMS based post-processing steps in a CMOS compatible process. By virtue of its vertical position, the antenna is isolated from the lossy Si substrate and hence performs with a better efficiency as compared to the horizontal position. In addition, the movable plate concept enables polarization diversity by providing both horizontal and vertical polarizations on the same chip. Through a first iteration fractal bowtie antenna design, dual band (60 and 77 GHz) operation is demonstrated in both horizontal and vertical positions without any change in dimensions or use of switches for two different mediums (Si and air). To support the movable plate concept, the transmission line and antenna are designed on a flexible polyamide, where the former has been optimized to operate in the bent position. The design is highly suitable for compact, low cost and efficient SoC solutions. © 1963-2012 IEEE.

Stress transmission in soil

DEFF Research Database (Denmark)

Lamandé, Mathieu; Schjønning, Per

We urgently need increased quantitative knowledge on stress transmission in real soils loaded with agricultural machinery. 3D measurements of vertical stresses under tracked wheels were performed in situ in a Stagnic Luvisol (clay content 20 %) continuously cropped with small grain cereals......). Seven load cells were inserted horizontally from a pit with minimal disturbance of soil in each of three depths (0.3, 0.6 and 0.9 m), covering the width of the wheeled area. The position of the wheel relative to the transducers was recorded using a laser sensor. Finally, the vertical stresses near...... the soil-tyre interface were measured in separate tests by 17 stress transducers across the width of the tyres. The results showed that the inflation pressure controlled the level of maximum stresses at 0.3 m depth, while the wheel load was correlated to the measured stresses at 0.9 m depth. This supports...

Dynamic characteristic analysis of mother to child transmission of HIV in India

Directory of Open Access Journals (Sweden)

A. S. Kadi

2014-01-01

Full Text Available In this study, a mathematical model of HIV/AIDS mother to child transmission to analyze the effectiveness of prevention of HIV mother to child transmission programmes has been presented. The result reveals that prevention of HIV mother to child transmission programmes focusing only on biological transmission cannot control the increase of the HIV mother to child transmission in India. Hence, to control the HIV MTCT epidemic in India, in spite of strengthening the PMTCT programmes to reduce transmission rates, effective measures should be taken to prevent HIV infection in women of reproductive ages. Since the overall HIV MTCT epidemic is dependent on the HIV incidence in women of reproductive age group, the integration of pediatric HIV model with a detailed model of adult HIV would be investigated in future studies in order to model these dynamics more accurately.

MoS2 Nanosheets Vertically Grown on Carbonized Corn Stalks as Lithium-Ion Battery Anode.

Science.gov (United States)

Ma, Luxiang; Zhao, Binglu; Wang, Xusheng; Yang, Junfeng; Zhang, Xinxiang; Zhou, Yuan; Chen, Jitao

2018-06-25

In this study, MoS 2 nanosheets are vertically grown on the inside and outside surfaces of the carbonized corn stalks (CCS) by a simple hydrothermal reaction. The vertically grown structure can not only improve the transmission rate of Li + and electrons but also avoid the agglomeration of the nanosheets. Meanwhile, a new approach of biomass source application is presented. We use CCS instead of graphite powders, which can not only avoid the exploitation of graphite resources, but also be used as a matrix for MoS 2 growth to prevent the electrode from being further decomposed during long cycles and at high current densities. Meanwhile, lithium-ion batteries show remarkable electrochemical performance. They demonstrate a high specific capacity of 1409.5 mA g -1 at 100 mA g -1 in the initial cycle. After 250 cycles, the discharge capacity is still as high as 1230.9 mAh g -1 . Even at 4000 mA g -1 , they show a high specific capacity of 777.7 mAh g -1 . Furthermore, the MoS 2 /CCS electrodes show long cycle life, and the specific capacity is still up to ∼500 mAh g -1 at 5000 mA g -1 after 1000 cycles.

Does Nigeria need the birth dose of the hepatitis B vaccine? | Sadoh ...

African Journals Online (AJOL)

The control of hepatitis B infection involves several strategies of which the most effective is vaccination. Schedules which include a birth dose (which can prevent vertical transmission when administered within 24 hours of birth) are recommended for use in countries with a high rate of vertical transmission. Nigeria is highly ...

Evaluation of 4 weeks' neonatal antiretroviral prophylaxis as a component of a prevention of mother-to-child transmission program in a resource-rich setting.

LENUS (Irish Health Repository)

Ferguson, Wendy

2011-05-01

In resource-rich settings, universal adoption of a 4- rather than 6-week neonatal antiretroviral (ARV) prophylaxis regimen could reduce toxicity and results in cost savings, provided prevention of mother-to-child transmission program effectiveness is not compromised.

Using Multiple Outcomes of Sexual Behavior to Provide Insights Into Chlamydia Transmission and the Effectiveness of Prevention Interventions in Adolescents.

Science.gov (United States)

Enns, Eva Andrea; Kao, Szu-Yu; Kozhimannil, Katy Backes; Kahn, Judith; Farris, Jill; Kulasingam, Shalini L

2017-10-01

Mathematical models are important tools for assessing prevention and management strategies for sexually transmitted infections. These models are usually developed for a single infection and require calibration to observed epidemiological trends in the infection of interest. Incorporating other outcomes of sexual behavior into the model, such as pregnancy, may better inform the calibration process. We developed a mathematical model of chlamydia transmission and pregnancy in Minnesota adolescents aged 15 to 19 years. We calibrated the model to statewide rates of reported chlamydia cases alone (chlamydia calibration) and in combination with pregnancy rates (dual calibration). We evaluated the impact of calibrating to different outcomes of sexual behavior on estimated input parameter values, predicted epidemiological outcomes, and predicted impact of chlamydia prevention interventions. The two calibration scenarios produced different estimates of the probability of condom use, the probability of chlamydia transmission per sex act, the proportion of asymptomatic infections, and the screening rate among men. These differences resulted in the dual calibration scenario predicting lower prevalence and incidence of chlamydia compared with calibrating to chlamydia cases alone. When evaluating the impact of a 10% increase in condom use, the dual calibration scenario predicted fewer infections averted over 5 years compared with chlamydia calibration alone [111 (6.8%) vs 158 (8.5%)]. While pregnancy and chlamydia in adolescents are often considered separately, both are outcomes of unprotected sexual activity. Incorporating both as calibration targets in a model of chlamydia transmission resulted in different parameter estimates, potentially impacting the intervention effectiveness predicted by the model.

The echolocation transmission beam of free-ranging Indo-Pacific humpback dolphins (Sousa chinensis).

Science.gov (United States)

Fang, Liang; Wu, Yuping; Wang, Kexiong; Pine, Matthew K; Wang, Ding; Li, Songhai

2017-08-01

While the transmission beam of odontocetes has been described in a number of studies, the majority of them that have measured the transmission beam in two dimensions were focused on captive animals. Within the current study, a dedicated cross hydrophone array with nine elements was used to investigate the echolocation transmission beam of free-ranging Indo-Pacific humpback dolphins. A total of 265 on-axis clicks were analyzed, from which the apparent peak to peak source levels ranged between 168 to 207 dB (mean 184.5 dB ± 6.6 dB). The 3-dB beam width along the horizontal and vertical plane was 9.6° and 7.4°, respectively. Measured separately, the directivity index of the horizontal and vertical plane was 12.6 and 13.5 dB, respectively, and the overall directivity index (both planes combined) was 29.5 dB. The beam shape was slightly asymmetrical along the horizontal and vertical axis. Compared to other species, the characteristics of the transmitting beam of Indo-Pacific humpback dolphins were relatively close to the bottlenose dolphin (Tursiops truncatus), likely due to the similarity in the peak frequency and waveform of echolocation clicks and comparable body sizes of the two species.

Malaria infection during pregnancy in area of stable transmission ...

African Journals Online (AJOL)

Malaria infection during pregnancy in area of stable transmission. ... (LBW), a leading cause of neonatal death in areas of stable malaria transmission. ... areas of stable malaria transmission and the effective strategies for prevention and control. Keywords: malaria, pregnancy, semi-immune women, anaemia, low birthweight

Vertical-axis turbine/propeller for ship propulsion

Energy Technology Data Exchange (ETDEWEB)

Barkla, H.M.

1984-01-01

There are so many variables in the design and operating conditions of a vertical-axis turbine/propeller for the propulsion of a ship by wind that a preliminary study is offered, based on two simplified models. Study of a linear motion of blades in air and water shows optimum conditions for blade-speed and blade-incidence. Analysis of the second, cyclical model is simplified by the assumption of constant angles of incidence. While the logical superiority of the vertical-axis system, with its low transmission loss, may not alone give it the advantage over all other systems in upwind and downwind sailing, there are indications that in the beam wind it is in a class of its own; the Voith-Schneider-Type propeller then produces a thrust with a major component to windward, so that the combined unit leaves little or no athwartships force.

Increased risk of mother-to-infant transmission of hepatitis C virus by intrapartum infantile exposure to maternal blood.

Science.gov (United States)

Steininger, Christoph; Kundi, Michael; Jatzko, Gerlinde; Kiss, Herbert; Lischka, Andreas; Holzmann, Heidemarie

2003-02-01

Virological and clinical data from 73 hepatitis C virus (HCV)-infected pregnant women who gave birth to 75 children were merged retrospectively, by logistic regression analysis, to investigate risk factors for vertical transmission of HCV. Eighty-two percent of the HCV-infected mothers were HCV-RNA-positive during pregnancy, and 10% were coinfected with human immunodeficiency virus (HIV). Nine children were HCV infected, 1 was HIV infected, but none was HIV-HCV coinfected. Among vaginal deliveries, the mean HCV load of mothers who transmitted HCV to their infants was higher than that of those who did not (8.1 x 10(5) vs. 1.4 x 10(4) copies/mL; P=.056). A reduction in umbilical cord-blood pH (relative risk, 3.9; P=.04) or the occurrence of perineal or vaginal laceration (relative risk, 6.4; P=.028) during vaginal delivery significantly increased the risk of vertical HCV transmission. In conclusion, high maternal viremia, infantile hypoxia, and intrapartum exposure to virus-contaminated maternal blood increased the risk of HCV transmission during vaginal deliveries. Consequently, cesarean section may reduce the risk of vertical HCV transmission in selected cases.

Collective effect of personal behavior induced preventive measures and differential rate of transmission on spread of epidemics

Science.gov (United States)

Sagar, Vikram; Zhao, Yi

2017-02-01

In the present work, the effect of personal behavior induced preventive measures is studied on the spread of epidemics over scale free networks that are characterized by the differential rate of disease transmission. The role of personal behavior induced preventive measures is parameterized in terms of variable λ, which modulates the number of concurrent contacts a node makes with the fraction of its neighboring nodes. The dynamics of the disease is described by a non-linear Susceptible Infected Susceptible model based upon the discrete time Markov Chain method. The network mean field approach is generalized to account for the effect of non-linear coupling between the aforementioned factors on the collective dynamics of nodes. The upper bound estimates of the disease outbreak threshold obtained from the mean field theory are found to be in good agreement with the corresponding non-linear stochastic model. From the results of parametric study, it is shown that the epidemic size has inverse dependence on the preventive measures (λ). It has also been shown that the increase in the average degree of the nodes lowers the time of spread and enhances the size of epidemics.

The costs and benefits of Option B+ for the prevention of mother-to-child transmission of HIV.

Science.gov (United States)

Gopalappa, Chaitra; Stover, John; Shaffer, Nathan; Mahy, Mary

2014-01-01

Most countries follow WHO 2010 guidelines for the prevention of mother-to-child transmission (PMTCT) of HIV using either Option A or B for women not yet eligible for antiretroviral therapy (ART). Both of these approaches involve the use of antiretrovirals during pregnancy and breastfeeding. Some countries have adopted a new strategy, Option B+, in which HIV-positive pregnant women are started immediately on ART and continued for life. Option B+ is more costly than Options A or B, but provides additional health benefits. In this article, we estimate the additional costs and effectiveness of Option B+. We developed a deterministic model to simulate births, breastfeeding, and HIV infection in women in four countries, Kenya, Zambia, South Africa, and Vietnam that differ in fertility rate, birth interval, age at first birth, and breastfeeding patterns, but have similar age at HIV infection. We estimated the total PMTCT costs and new child infections under Options A, B, and B+, and measured cost-effectiveness as the incremental PMTCT-related costs per child infection averted. We included adult sexual transmissions averted from ART, the corresponding costs saved, and estimated the total incremental cost per transmission (child and adult) averted. When considering PMTCT-related costs and child infections, Option B+ was the most cost-effective strategy costing between $6000 and $23 000 per infection averted compared with Option A. Option B+ averted more child infections compared with Option B in all four countries and cost less than Option B in Kenya and Zambia. When including adult sexual transmissions averted, Option B+ cost less and averted more infections than Options A and B.

Impact of a Web-based intervention on maternal caries transmission and prevention knowledge, and oral health attitudes.

Science.gov (United States)

Albert, David; Barracks, Sharifa Z; Bruzelius, Emilie; Ward, Angela

2014-09-01

Poor oral health knowledge is thought to significantly contribute to the incidence of early childhood caries, the most common childhood disease in the U.S. This study assessed the effectiveness of a web-based educational program in increasing oral health and caries transmission knowledge, attitudes and planned behavior among mothers and primary caregivers. Study participants were recruited from subscribers to an online health information newsletter distributed by a national dental insurance company and from visitors to a health information website sponsored by the same company. Participants completed pre- and post-intervention surveys and viewed a brief educational program. Results were analyzed for pre- to post-test changes in knowledge and attitudes. Planned behavior change was also assessed. 459 participants completed pre-and post-test surveys. The sample was typically more insured (91.3 %), and college educated (76.9 %), than the general population. At baseline, respondents were knowledgeable about caries and its prevention; however, their specific knowledge about caries transmission was limited. There was a significant increase in caries knowledge from baseline to follow-up, particularly regarding caries transmission. At baseline less than half of the participants (48.8 %) knew that mothers/primary caregivers play a large role in passing cavity causing germs to children and 43.1 % knew that there is a defined period of time when the risk of transmission of cariogenic bacteria is greatest; however in post-testing 99.6 % and 98.3 % answered these question correctly respectively (p education to primary caregivers can be an effective and low cost strategy for promoting maternal and infant oral health.

Transmission embedded cost allocation methodology with consideration of system reliability

International Nuclear Information System (INIS)

Hur, D.; Park, J.-K.; Yoo, C.-I.; Kim, B.H.

2004-01-01

In a vertically integrated utility industry, the cost of reliability, as a separate service, has not received much rigorous analysis. However, as a cornerstone of restructuring the industry, the transmission service pricing must change to be consistent with, and supportive of, competitive wholesale electricity markets. This paper focuses on the equitable allocation of transmission network embedded costs including the transmission reliability cost based on the contributions of each generator to branch flows under normal conditions as well as the line outage impact factor under a variety of load levels. A numerical example on a six-bus system is given to illustrate the applications of the proposed methodology. (author)

Extended Microbiological Characterization of Göttingen Minipigs in the Context of Xenotransplantation: Detection and Vertical Transmission of Hepatitis E Virus.

Directory of Open Access Journals (Sweden)

Vladimir A Morozov

Full Text Available Xenotransplantation has been proposed as a solution to the shortage of suitable human donors. Pigs are currently favoured as donor animals for xenotransplantation of cells, including islet cells, or organs. To reduce the xenotransplantation-associated risk of infection of the recipient the pig donor should be carefully characterised. Göttingen minipigs from Ellegaard are often used for biomedical research and are regularly tested by their vendor for the presence of numerous bacteria, fungi, viruses and parasites. However, screening for some pathogens transmittable to humans had not been performed.The presence of microorganisms was examined in Göttingen Minipigs by PCR methods. Since zoonotic transmission of porcine hepatitis E virus HEV to humans has been demonstrated, extended search for HEV was considered as a priority. RNA from sera, islet and other cells from 40 minipigs were examined for HEV using different real-time reverse transcription (RT-PCRs, among them two newly established. In addition, sera were examined by Western blot analysis using two recombinant capsid proteins of HEV as antigens. HEV RNA was not detected in pigs older than one year including gilts, but it was detected in the sera of three of ten animals younger than 1 year. Furthermore, HEV was also detected in the sera of three sows six days after delivery and their offspring, indicating vertical transmission of the virus. PCR amplicons were cloned, sequenced and the viruses were found to belong to the HEV genotype (gt 3/4. Anti-HEV immunoglobulins G were detected in one sow and maternal antibodies in her six day old piglet. Since Göttingen minipigs were negative for many xenotransplantation-relevant microorganisms, they can now be classified as safe. HEV may be eliminated from the Ellegaard herd by selection of negative animals and/or by treatment of the animals.

Combined VIS-IR spectrometer with vertical probe beam

Science.gov (United States)

Protopopov, V.

2017-12-01

A prototype of a combined visible-infrared spectrometer with a vertical probe beam is designed and tested. The combined spectral range is 0.4-20 μ with spatial resolution 1 mm. Basic features include the ability to measure both visibly transparent and opaque substances, as well as buried structures, such as in semiconductor industry; horizontal orientation of a sample, including semiconductor wafers; and reflection mode of operation, delivering twice the sensitivity compared to the transmission mode.

Study of genetic damage in the Japanese oyster induced by an environmentally-relevant exposure to diuron: evidence of vertical transmission of DNA damage.

Science.gov (United States)

Barranger, A; Akcha, F; Rouxel, J; Brizard, R; Maurouard, E; Pallud, M; Menard, D; Tapie, N; Budzinski, H; Burgeot, T; Benabdelmouna, A

2014-01-01

Pesticides represent a major proportion of the chemical pollutants detected in French coastal waters and hence a significant environmental risk with regards to marine organisms. Commercially-raised bivalves are particularly exposed to pollutants, among them pesticides, as shellfish farming zones are subject to considerable pressure from agricultural activities on the mainland. The aims of this study were to determine (1) the genotoxic effects of diuron exposure on oyster genitors and (2) the possible transmission of damaged DNA to offspring and its repercussions on oyster fitness. To investigate these points, oysters were exposed to concentrations of diuron close to those detected in the Marennes-Oleron Basin (two 7-day exposure pulses at 0.4 and 0.6 μg L(-1)) during the gametogenesis period. Genomic abnormalities were characterized using two complementary approaches. The Comet assay was applied for the measurement of early and reversible primary DNA damage, whereas flow cytometry was used to assess the clastogenic and aneugenic effect of diuron exposure. Polar Organic Chemical Integrative Samplers (POCIS) were used in exposed and assay tanks to confirm the waterborne concentration of diuron reached during the experiment. The results obtained by the Comet assay clearly showed a higher level of DNA strand breaks in both the hemocytes and spermatozoa of diuron-exposed genitors. The transmission of damaged genetic material to gamete cells could be responsible for the genetic damage measured in offspring. Indeed, flow cytometry analyses showed the presence of DNA breakage and a significant decrease in DNA content in spat from diuron-exposed genitors. The transmission of DNA damage to the offspring could be involved in the negative effects observed on offspring development (decrease in hatching rate, higher level of larval abnormalities, delay in metamorphosis) and growth. In this study, the vertical transmission of DNA damage was so highlighted by subjecting oyster

Structure and optical anisotropy of vertically correlated submonolayer InAs/GaAs quantum dots

DEFF Research Database (Denmark)

Xu, Zhangcheng; Birkedal, Dan; Hvam, Jørn Märcher

2003-01-01

A vertically correlated submonolayer (VCSML) InAs/GaAs quantum-dot (QD) heterostructure was studied using transmission electron microscopy, high-resolution x-ray diffraction (HRXRD) and polarization-dependent photoluminescence. The HRXRD (004) rocking curve was simulated using the Tagaki-Taupin...

Optical transmission through multi-component generalized Thue-Morse superlattices

Energy Technology Data Exchange (ETDEWEB)

Zhang Guogang [MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, South China Normal University, Guangzhou 510631 (China); Yang Xiangbo, E-mail: xbyang@scnu.edu.c [MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, South China Normal University, Guangzhou 510631 (China); Li Yuhong; Song Huanhuan [MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, South China Normal University, Guangzhou 510631 (China)

2010-09-01

In this paper, by the three kinds of basic components (BCs) of three-component Thue-Morse (3CTM) sequence we construct a type of interesting optical basic-structural-units (BSUs) and propose multi-component generalized Thue-Morse (mCGTM) model. Based on the conventional electromagnetic wave theory we investigate the optical transmission vertically through the one-dimensional (1D) mCGTM superlattices. It is found that the optical transmission possesses an interesting pseudo-constant characteristic at the central wavelength. mCGTM sequence exhibits a cantor-set structure which results in the system possessing certain kinds of effective component pairs (ECPs), and each kind of ECP brings about certain contribution towards the optical transmission. The cantor-set structure is the reason that mCGTM multilayers exhibit the optical transmission pseudo-constant property. For the pseudo-constant optical transmission of mCGTM superlattices, there would be a potential application in the designing of some complex optical devices.

Determinations of vertical stroke V{sub cb} vertical stroke and vertical stroke V{sub ub} vertical stroke from baryonic Λ{sub b} decays

Energy Technology Data Exchange (ETDEWEB)

Hsiao, Y.K. [Shanxi Normal University, School of Physics and Information Engineering, Linfen (China); National Tsing Hua University, Department of Physics, Hsinchu (China); Geng, C.Q. [Shanxi Normal University, School of Physics and Information Engineering, Linfen (China); National Tsing Hua University, Department of Physics, Hsinchu (China); Hunan Normal University, Synergetic Innovation Center for Quantum Effects and Applications (SICQEA), Changsha (China)

2017-10-15

We present the first attempt to extract vertical stroke V{sub cb} vertical stroke from the Λ{sub b} → Λ{sub c}{sup +}l anti ν{sub l} decay without relying on vertical stroke V{sub ub} vertical stroke inputs from the B meson decays. Meanwhile, the hadronic Λ{sub b} → Λ{sub c}M{sub (c)} decays with M = (π{sup -},K{sup -}) and M{sub c} =(D{sup -},D{sup -}{sub s}) measured with high precisions are involved in the extraction. Explicitly, we find that vertical stroke V{sub cb} vertical stroke =(44.6 ± 3.2) x 10{sup -3}, agreeing with the value of (42.11 ± 0.74) x 10{sup -3} from the inclusive B → X{sub c}l anti ν{sub l} decays. Furthermore, based on the most recent ratio of vertical stroke V{sub ub} vertical stroke / vertical stroke V{sub cb} vertical stroke from the exclusive modes, we obtain vertical stroke V{sub ub} vertical stroke = (4.3 ± 0.4) x 10{sup -3}, which is close to the value of (4.49 ± 0.24) x 10{sup -3} from the inclusive B → X{sub u}l anti ν{sub l} decays. We conclude that our determinations of vertical stroke V{sub cb} vertical stroke and vertical stroke V{sub ub} vertical stroke favor the corresponding inclusive extractions in the B decays. (orig.)

Characteristics of Wave Reflection for Vertical and Slit Caissons with Porous Structures

Directory of Open Access Journals (Sweden)

Tae-Hwa Jung

2012-01-01

Full Text Available Offshore structures are occasionally located at a relatively deep water region, the outside of breakwater. In this case, these structures may be damaged by the supposition of incident and reflected waves from a vertical breakwater. To prevent the damage, the reflected waves are controlled by installing porous structures at the face of the vertical breakwater. In this study, numerical experiments are carried out to identify the characteristics of wave reflection from the porous structures installing in front of a vertical or slit caisson.

Comparison of anti-retroviral therapy treatment strategies in prevention of mother-to-child transmission in a teaching hospital in Ethiopia.

Science.gov (United States)

Kumela, Kabaye; Amenu, Demisew; Chelkeba, Legese

2015-01-01

More than 90% of Human immunodeficiency virus (HIV) infection in children is acquired due to mother-to-child transmission, which is spreading during pregnancy, delivery or breastfeeding. To determine the effectiveness of highly active antiretroviral and short course antiretroviral regimens in prevention of mother-to-child transmission of HIV and associated factors Jimma University Specialized Hospital (JUSH). A hospital based retrospective cohort study was conducted on HIV infected pregnant mothers who gave birth and had follow up at anti-retroviral therapy (ART) clinic for at least 6 months during a time period paired with their infants. The primary and secondary outcomes were rate of infant infection by HIV at 6 weeks and 6 months respectively. The Chi-square was used for the comparison of categorical data multivariate logistic regression model was used to identify the determinants of early mother-to-child transmission of HIV at 6 weeks. Cox proportional hazard model was used to analyze factors that affect the 6 month HIV free survival of infants born to HIV infected mothers. A total of 180 mother infant pairs were considered for the final analysis, 90(50%) mothers received single dose nevirapine (sdNVP) designated as regimen-3, 67 (37.2%) mothers were on different types of ARV regimens commonly AZT + 3TC + NVP (regimen-1), while the rest 23 (12.8%) mothers were on short course dual regimen AZT + 3TC + sdNVP (regimen-2). Early mother-to-child transmission rate at 6 weeks for regimens 1, 2 and 3 were 5.9% (4/67), 8.6% (2/23), and 15.5% (14/90) respectively. The late cumulative mother-to-child transmission rate of HIV at 6 months regardless of regimen type was 15.5% (28/180). Postnatal transmission at 6 months was 28.5% (8/28) of infected children. Factors that were found to be associated with high risk of early mother-to-child transmission of HIV include duration of ARV regimen shorter than 2 months during pregnancy (OR=4.3, 95%CI =1.38-13.46), base line CD4 less

Transmission of chimeric HIV by mating in conventional mice: prevention by pre-exposure antiretroviral therapy and reduced susceptibility during estrus

Directory of Open Access Journals (Sweden)

Eran Hadas

2013-09-01

Heterosexual transmission accounts for the majority of new human immunodeficiency virus (HIV cases worldwide. The current approach to investigate HIV heterosexual transmission in animals involves application of virus stock to the vaginal surface, a method that does not reproduce the physiological conditions of vaginal intercourse that influence the rate of transmission. We have previously described efficient infection of conventional mice using EcoHIV/NL4-3 and EcoHIV/NDK, chimeric HIV molecular clones constructed to express all HIV structural and regulatory genes except envelope, which is replaced by a rodent-tropic envelope gene. Here we investigated whether EcoHIV/NDK-infected male mice transmit virus to females during coitus, and the sensitivity of this transmission to HIV pre-exposure prophylaxis and the estrus state. Our general approach was to allow mating between EcoHIV/NDK-infected male mice and uninfected females for 1–7 nights. At 1–6 weeks after mating, mice were euthanized and virus burdens were measured by quantitative PCR (qPCR amplification of HIV RNA or DNA in peritoneal macrophages, inguinal lymph node cells, spleen cells or vas deferens, or by ELISA for antibodies to HIV Gag. We found that 70–100% of female mice mated to EcoHIV/NDK-infected males acquired infection. Pericoital treatment of females with either 2′,3′-dideoxcytidine (ddC or tenofovir largely prevented their EcoHIV/NDK infection by mating (P<0.05 and P<0.003, respectively. In males, T cells were dispensable for virus transmission. The rate of EcoHIV/NDK sexual transmission to females in estrus declined sharply (P=0.003 but their infection by injection was unaffected, indicating that the local environment in the female reproductive tract influences susceptibility to HIV. We conclude that this system of EcoHIV/NDK transmission during mouse mating reproduces key features of heterosexual transmission of HIV in humans and can be used to investigate its biology and control.

Quasioptical devices based on extraordinary transmission at THz

Science.gov (United States)

Beruete, Miguel

2016-04-01

In this work I will present our latest advances in components developed from extraordinary transmission concepts operating at terahertz (THz) frequencies. First, a structure exhibiting two different extraordinary transmission resonances depending on the polarization of the incident wave will be shown. The peaks of transmission appear at approximately 2 and 2.5 THz for vertical and horizontal polarization, respectively, with a transmittance above 60% in both cases. Later on, a meandering line structure able to tune the extraordinary transmission resonance will be discussed. The operation frequency in this case is between 9 and 17 THz. A self-complementary polarizer will be then presented, with a high polarization purity. The fundamentals of this device based on the Babinet's principle will be discussed in depth. Finally, all these structures will be combined together to produce a dual-band Quarter Wave Plate able to convert a linear polarization at the input in a circular polarization at the output at two different bands, 1 and 2.2. THz. Some final words regarding the potential of extraordinary transmission for sensing applications will close the contribution.

Resource Manual for Handling Body Fluids in the School Setting To Prevent the Transmission of Human Immunodeficiency Virus and Hepatitis B Virus.

Science.gov (United States)

Maryland State Dept. of Health and Mental Hygiene, Baltimore.

Guidelines to prevent the transmission of blood-borne diseases, especially those caused by the Human Immunodeficiency Virus (HIV) and the Hepatitis B Virus (HBV), in the school setting are provided in this resource manual for school staff. Sections include information on the reasons for the development of this manual; a summary of the means of HIV…

Transplacental and oral transmission of wild-type bluetongue virus serotype 8 in cattle after experimental infection

NARCIS (Netherlands)

Backx, A.; Heutink, C.G.; Rooij, van E.M.A.; Rijn, van P.A.

2009-01-01

Potential vertical transmission of wild-type bluetongue virus serotype 8 (BTV-8) in cattle was explored in this experiment. We demonstrated transplacental transmission of wild-type BTV-8 in one calf and oral infection with BTV-8 in another calf. Following the experimental BTV-8 infection of seven

Resource Manual for Handling Body Fluids in the School Setting To Prevent Transmission of Human Immunodeficiency Virus and Hepatitis B Virus. Revised Edition.

Science.gov (United States)

Maryland State Dept. of Health and Mental Hygiene, Baltimore.

This Maryland resource manual provides local education agencies with guidelines on how to handle body fluids to prevent the transmission of diseases, especially Human Immunodeficiency Virus (HIV) and Hepatitis B Virus (HBV), in the school setting. The first section summarizes the reasons for development of the manual. The second section summarizes…

Infant feeding practice and associated factors of HIV positive mothers attending prevention of mother to child transmission and antiretroviral therapy clinics in Gondar Town health institutions, Northwest Ethiopia

Directory of Open Access Journals (Sweden)

Muluye Dagnachew

2012-03-01

Full Text Available Abstract Background It has been estimated that 430,000 children under 15 years of age were newly infected with HIV in 2008, and more than 71% are living in sub-Saharan Africa. In the absence of intervention to prevent mother-to-child transmission, 30-45% of infants born to HIV-positive mothers in developing countries become infected during pregnancy, delivery and breastfeeding. The aim of this study was to assess infant feeding practice and associated factors of HIV positive mothers attending prevention of mother to child transmission and antiretroviral therapy clinics of Northwest Ethiopia. Methods Institution based cross sectional study was conducted from January to May 2011 among all HIV positive mothers with less than two years old child attending prevention of mother to child transmission and antiretroviral therapy clinics in Gondar Town health institutions. A structured pre-tested questionnaire using interview technique was used for data collection. The data was entered and analyzed using SPSS version 16 statistical package. Results A total of 209 HIV positive mothers were included in the study. Of these, 187 (89.5% had followed the recommended way of infant feeding practice while significant percentage (10.5% had practiced mixed breast feeding. In multivariate analysis, disclosure of HIV status with their spouse, insufficient breast milk and occupational status were found to be independently associated (p-value of Conclusions Higher proportion of respondents used the recommended way of infant feeding practice by WHO as well as by Ethiopian Ministry of Health. However, mixed feeding in the first 6 months of age, an undesirable practice in infant feeding, were reported in this study. Infant feeding education that is aligned to national policy should be strengthened in primary health care, particularly in situations where prevention of mother to child transmission of HIV is prioritized.

HIV type 1 chemokine receptor usage in mother-to-child transmission.

Science.gov (United States)

Salvatori, F; Scarlatti, G

2001-07-01

To investigate the role of the HIV-1 phenotype in mother-to-child HIV-1 transmission, we evaluated coreceptor usage and replication kinetics in chemokine receptor-expressing U87MG.CD4 cells of primary isolates from 32 HIV-1-infected mothers of Italian origin, none under preventive antiretroviral therapy, and from their infected infants. Five of 15 mothers of infected children and 2 of 17 mothers of uninfected children harbored viruses able to use CXCR4 as coreceptor. However, all isolates used CCR5, alone or in association with CXCR4. The replicative capacity in coreceptor-expressing cells of the viral isolates did not differ between the two groups of mothers. All mothers with an R5 virus transmitted a virus with the same coreceptor usage, whereas those four with a multitropic virus transmitted such a virus in one case. Although the presence of a mixed viral population was documented in the mothers, we did not observe transmission solely of X4 viruses. Interestingly, the only child infected with a multitropic virus carried a defective CCR5 allele. Analysis of the env V3 region of the provirus from this child revealed infection with multiple viral variants with a predominance of R5-type over X4-type sequences. These findings show that CCR5 usage of a viral isolate is not a discriminating risk factor for vertical transmission. Furthermore, X4 viruses can be transmitted to the newborn, although less frequently. In particular, we document the transmission of multiple viral variants with different coreceptor usage in a Delta32 CCR5 heterozygous child, and demonstrate that the heterozygous genotype per se does not contribute to the restriction of R5-type virus spread.

Vertical pump with free floating check valve

International Nuclear Information System (INIS)

Lindsay, M.

1980-01-01

A vertical pump is described which has a bottom discharge with a free floating check valve disposed in the outlet plenum thereof. The free floating check valve comprises a spherical member with a hemispherical cage-like member attached thereto which is capable of allowing forward or reverse flow under appropriate conditions while preventing reverse flow under inappropriate conditions

Iridium catalyzed growth of vertically aligned CNTs by APCVD

International Nuclear Information System (INIS)

Sahoo, R.K.; Jacob, C.

2014-01-01

Highlights: • Growth of uniform-diameter vertically-aligned multi-walled CNTs by APCVD. • Use of high melting point low carbon solubility iridium nanoparticles as catalyst. • Optimization of growth time for uniform sized, uniformly aligned CNTs. • Growth model for the various features in the vertically aligned CNTs is proposed. - Abstract: Vertically aligned carbon nanotubes (VA-CNTs) have been synthesized using high temperature catalyst nanoparticles of iridium. The catalyst layer was prepared by DC sputtering. Particle density, circularity and average particle size of the catalyst were analyzed using field emission scanning electron microscopy. The alignment, morphology and the length of the as-grown CNTs were analyzed using field-emission scanning electron microscopy. High resolution transmission electron microscopy was carried out to observe the layers of graphitic stacking which form the carbon nanotubes. Micro Raman measurement was used for the analysis of the graphitic crystallinity of the as-grown carbon nano structures. Effects of growth time variation on growth morphology and alignment have been studied. The alignment has been explained on the basis of the crowding effect of the neighboring nanoparticles

Iridium catalyzed growth of vertically aligned CNTs by APCVD

Energy Technology Data Exchange (ETDEWEB)

Sahoo, R.K.; Jacob, C., E-mail: cxj14_holiday@yahoo.com

2014-07-01

Highlights: • Growth of uniform-diameter vertically-aligned multi-walled CNTs by APCVD. • Use of high melting point low carbon solubility iridium nanoparticles as catalyst. • Optimization of growth time for uniform sized, uniformly aligned CNTs. • Growth model for the various features in the vertically aligned CNTs is proposed. - Abstract: Vertically aligned carbon nanotubes (VA-CNTs) have been synthesized using high temperature catalyst nanoparticles of iridium. The catalyst layer was prepared by DC sputtering. Particle density, circularity and average particle size of the catalyst were analyzed using field emission scanning electron microscopy. The alignment, morphology and the length of the as-grown CNTs were analyzed using field-emission scanning electron microscopy. High resolution transmission electron microscopy was carried out to observe the layers of graphitic stacking which form the carbon nanotubes. Micro Raman measurement was used for the analysis of the graphitic crystallinity of the as-grown carbon nano structures. Effects of growth time variation on growth morphology and alignment have been studied. The alignment has been explained on the basis of the crowding effect of the neighboring nanoparticles.

Infection control and prevention practices implemented to reduce transmission risk of Middle East respiratory syndrome-coronavirus in a tertiary care institution in Saudi Arabia.

Science.gov (United States)

Butt, Taimur S; Koutlakis-Barron, Irene; AlJumaah, Suliman; AlThawadi, Sahar; AlMofada, Saleh

2016-05-01

Transmission of Middle East respiratory syndrome-coronavirus (MERS-CoV) among health care workers (HCWs) and patients has been documented with mortality rate approximating 36%. We propose advanced infection control measures (A-IC) used in conjunction with basic infection control measures (B-IC) help reduce pathogen transmission. B-IC include standard and transmission-based precautions. A-IC are initiatives implemented within our center to enhance effectiveness of B-IC. Study effectiveness of combining B-IC and A-IC to prevent transmission of MERS-CoV to HCWs. A retrospective observational study was undertaken. A-IC measures include administrative support with daily rounds; infection control risk assessment; timely screening, isolation, and specimen analysis; collaboration; epidemic planning; stockpiling; implementation of contingency plans; full personal protective equipment use for advanced airway management; use of a real-time electronic isolation flagging system; infection prevention and control team on-call protocols; pretransfer MERS-CoV testing; and education. A total of 874 real-time polymerase chain reaction MERS-CoV tests were performed during the period beginning July 1, 2013, and ending January 31, 2015. Six hundred ninety-four non-HCWs were tested, of these 16 tested positive for MERS-CoV and their infection was community acquired. Sixty-nine percent of the confirmed MERS-CoV-positive cases were men, with an average age of 56 years (range, 19-84 years). Of the total tested for MERS-CoV, 180 individuals were HCWs with zero positivity. Adhering to a combination of B-IC and A-IC reduces the risk of MERS-CoV transmission to HCWs. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Preventing perinatal HIV transmission - nowisthe time to act!

African Journals Online (AJOL)

been met with denial, procrastination and bungling. From a public health point of view this has been a disaster. Will we again miss the chance to act decisively when it comes to perinatal transmission? For African scientists to try to politicise criticism of placebo trials as intervention from the. West is wrong. Rather, they must ...

The role of drugs in HIV prevention

Science.gov (United States)

Kembaren, T.

2018-03-01

WHO reports 36.7 million people are living with Human Immunodeficiency Virus (HIV) worldwide by 2016 with about 1.8 million new infections each year. It will be a specific health problem for the world in both developed and developing countries so it is necessary strategies to reduce HIV transmission to the community. HIV transmission in people with risk factors is largely determined by the amount of virus in the blood of people who are the source of infection. Antiretroviral (ARV) therapy has long been used in HIV patients, which serves to suppress viral replication so that the patient’s immunity increases; opportunistic infections are resolved and prolong the lifespan and lower transmission rates. In the HIV Prevention Trials Network (HPTN) study 052 there was a 96% reduction in transmission in earlier antiretroviral. ARV is also used in the prevention of transmission in people exposed to HIV virus that is Postexposure Prophylaxis as well as in people at risk before exposure (Pre-exposure Prophylaxis). Three prevention strategies with the provision of ARV is expected to be guided as a means of prevention of transmission in addition to behavioral changes has long been declared since the beginning of the HIV epidemic.

Transmisión vertical del VIH: Comprendiendo el sentimiento de los padres por la técnica proyectiva HIV Vertical Transmission: Understanding the parents' feelings through the projective technique

Directory of Open Access Journals (Sweden)

Janie Maria de Almeida

2009-06-01

Full Text Available Estudio cualitativo realizado con padres de lactantes expuestos al VIH, cuya madre está inscrita en el Programa Transmisión Vertical Cero, Sorocaba, SP. El objetivo es identificar sentimientos relacionados con la fe religiosa de estos padres ante la indefinición del diagnóstico para el VIH del lactante. La investigación fue aprobada por un Comité de Ética en Investigación y siguió la Resolución 196/96. Para la recolección de datos se empleó la técnica proyectiva con montaje elaborada a partir de la pregunta "¿como ha sido para ustedes vivir el día-a-día esperando el resultado final de la prueba antiVIH del bebé?". La narrativa sobre su significado fue el paso siguiente. Se verificó que esta técnica fue eficiente para desencadenar el pensamiento de los participantes, para conducir y sustentar sus relatos. De los datos emergieron cinco temas, de los cuales destacamos religiosidad y espiritualidad que muestran que tienen fe y esperanza en un futuro saludable para el hijo expuesto al VIH.Qualitative study carried out with parents of newborn babies exposed to HIV whose mothers are registered at the Zero Vertical Transmission Program in Sorocaba, SP. The study aimed to identify feelings concerning the parents' religious faith while the baby seropositivity diagnosis for HIV is not defined yet. The research was approved by the Ethical Committee in Research according to Resolution 196/96. The projective technique was used for data collection in order to get answers for the following question: "how do you feel living your daily routine while you wait for your baby anti HIV test final result?" Speaking about its meaning was the next step. This technique has proved to be efficient in triggering the participants' thoughts and also in leading and supporting their reports. Five topics came up from the data collection; we highlighted two topics, religiosity and spirituality, which showed that having faith means being hopeful about the exposed

Nurturing the Continuum of HIV Testing, Treatment and Prevention Matrix Cascade in Reducing HIV Transmission.

Science.gov (United States)

Yah, Clarence S

2017-11-01

Despite the shift in antiretroviral therapy (ARVs) eligibility cascade from CD4 ≤ 200 to CD4 ≤ 350 to CD4 ≤ 500 mm 3 , HIV related morbidity and mortality continue to escalate annually, as do HIV infections. The new paradigm of treatment for all HIV positives individual irrespective of CD4 count may significantly reduce HIV and related illnesses. The author assumes that all HIV infected partners should be eligible for HIV treatment and care, irrespective of CD4 count. A second assumption is that high risk HIV negative partners have free access to continuum of HIV pre-exposure prophylaxis (PrEP), post exposure prophylaxis (PEP) and other prevention packages. A literature review search was used to extract evidence-based ARVs-HIV treatment and prevention interventions among HIV positives and high risk partners respectively. Only articles published in English and indexed in journal nuclei were used for the study. The information was used to nurture understanding of HIV treatment and prevention approaches as well as HIV incidence multiplier effect among HIV serodiscordant partners. The imputed HIV incident reference was assumed at 1.2 per 100 person-years (2). This was based on the imputation that retention in care, adherence and other predetermined factors are functions of an effective health care delivery system. The model showed a reduced HIV transmission from 1.2 per 100 person-years to 1.032 per 100 person-years in 6 months. The average threshold period of HIV suppressed partners on ARVs to an undetectable level. The combined multiplier protective-effect probability of transmitting HIV from HIV positive partners on ARVs-suppressed viremic load to HIV negative partners on PrEP/PEP-prevention was detected at 86. The model showed a significant reduction in HIV incidence. Placing serodiscordant sexual partners in HIV treatment and prevention plays a significant role in reducing and controlling HIV infection. Therefore, the policy of enrolling all HIV positives

Efficacy of sarolaner in the prevention of Borrelia burgdorferi and Anaplasma phagocytophilum transmission from infected Ixodes scapularis to dogs.

Science.gov (United States)

Honsberger, Nicole A; Six, Robert H; Heinz, Thomas J; Weber, Angela; Mahabir, Sean P; Berg, Thomas C

2016-05-30

The efficacy of sarolaner (Simparica™, Zoetis) to prevent transmission primarily of Borrelia burgdorferi and secondarily of Anaplasma phagocytophilum from infected wild-caught Ixodes scapularis to dogs was evaluated in a placebo-controlled laboratory study. Twenty-four purpose-bred laboratory Beagles seronegative for B. burgdorferi and A. phagocytophilum antibodies were allocated randomly to one of three treatment groups: placebo administered orally on Days 0 and 7, or sarolaner at 2mg/kg administered orally on Day 0 (28 days prior to tick infestation) or on Day 7 (21 days prior to tick infestation). On Day 28, each dog was infested with approximately 25 female and 25 male wild caught adult I. scapularis that were determined to have prevalence of 57% for B. burgdorferi and 6.7% for A. phagocytophilum by PCR. In situ tick counts were conducted on Days 29 and 30. On Day 33, all ticks were counted and removed. Acaricidal efficacy was calculated based on the reduction of geometric mean live tick counts in the sarolaner-treated groups compared to the placebo-treated group for each tick count. Blood samples collected from each dog on Days 27, 49, 63, 77, 91 and 104 were tested for the presence of B. burgdorferi and A. phagocytophilum antibodies using the SNAP(®) 4Dx(®) Plus Test, and quantitatively assayed for B. burgdorferi antibodies using an ELISA test. Skin biopsies collected on Day 104 were tested for the presence of B. burgdorferi by bacterial culture and PCR. Geometric mean live tick counts for placebo-treated dogs were 14.8, 12.8, and 19.1 on Days 29, 30, and 33, respectively. The percent reductions in mean live tick counts at 1, 2, and 5 days after infestation were 86.3%, 100%, and 100% for the group treated with sarolaner 21 days prior to infestation, and 90.9%, 97.1%, and 100% for the group treated with sarolaner 28 days prior to infestation. Geometric mean live tick counts for both sarolaner-treated groups were significantly lower than those for the

Iatrogenic Hepatitis C Virus Transmission and Safe Injection Practices.

Science.gov (United States)

Defendorf, Charles M; Paul, Sindy; Scott, George J

2018-05-01

Hepatitis C virus (HCV) infection poses significant adverse health effects. Improper use of vials, needles, syringes, intravenous bags, tubing, and connectors for injections and infusions is a current preventable cause of iatrogenic HCV transmission. Numerous cases have demonstrated the need for continued vigilance and the widespread nature of this iatrogenic infection risk across a variety of medical practice settings in the United States. Failure to implement the evidence-based Centers for Disease Control and Prevention (CDC) infection prevention guidelines exposes patients to preventable harm. The guidelines establish the requirement to notify patients in cases of suspected virus transmission, as well as to screen those patients who would not otherwise have been at risk for HCV seroconversion and other bloodborne pathogens. Legal and regulatory ramifications, including state, criminal, and tort laws, hold physicians and other health care professionals accountable to use safe injection practices. This article reviews the major health risks of HCV infection, significant effects of iatrogenic infection transmission, CDC guidelines for safe injection practices, and legal regulations and ramifications designed to promote safe injection practices.

Digital Photonic Receivers for Wireless and Wireline Optical Fiber Transmission Links

DEFF Research Database (Denmark)

Guerrero Gonzalez, Neil

services. The experimental demonstration supported the following transmissions systems: a baseband, 5 Gbps, intensity modulation system employing a directly modulated vertical cavity surface emitting laser (VCSEL), a baseband 20 Gbps non-return-to-zero quadrature phase-shift keying (NRZ-QPSK) system...... receivers in hybrid wireless and wireline optical fiber transmission links. Furthermore, the digital signal processing framework presented in this thesis can be extended to design probabilistic-based digital photonic receivers that can find applications in cognitive heterogeneous reconfigurable optical...

HIV Transmission Dynamics Among Foreign-Born Persons in the United States.

Science.gov (United States)

Valverde, Eduardo E; Oster, Alexandra M; Xu, Songli; Wertheim, Joel O; Hernandez, Angela L

2017-12-15

In the United States (US), foreign-born persons are disproportionately affected by HIV and differ epidemiologically from US-born persons with diagnosed HIV infection. Understanding HIV transmission dynamics among foreign-born persons is important to guide HIV prevention efforts for these populations. We conducted molecular transmission network analysis to describe HIV transmission dynamics among foreign-born persons with diagnosed HIV. Using HIV-1 polymerase nucleotide sequences reported to the US National HIV Surveillance System for persons with diagnosed HIV infection during 2001-2013, we constructed a genetic distance-based transmission network using HIV-TRACE and examined the birth region of potential transmission partners in this network. Of 77,686 people, 12,064 (16%) were foreign born. Overall, 28% of foreign-born persons linked to at least one other person in the transmission network. Of potential transmission partners, 62% were born in the United States, 31% were born in the same region as the foreign-born person, and 7% were born in another region of the world. Most transmission partners of male foreign-born persons (63%) were born in the United States, whereas most transmission partners of female foreign-borns (57%) were born in their same world region. These finding suggests that a majority of HIV infections among foreign-born persons in our network occurred after immigrating to the United States. Efforts to prevent HIV infection among foreign-born persons in the United States should include information of the transmission networks in which these individuals acquire or transmit HIV to develop more targeted HIV prevention interventions.

Human immunodeficiency virus (HIV) in pregnancy: a review of the guidelines for preventing mother-to-child transmission in Malaysia.

Science.gov (United States)

Azwa, Iskandar; Khong, Su Yen

2012-12-01

Mother-to-child transmission (MTCT) of human immunodefi ciency virus (HIV) is a devastating consequence of HIV infection during pregnancy and is largely preventable. Evidence-based interventions such as universal antenatal screening, provision of antiretroviral therapy, delivery by elective caesarean section and avoidance of breastfeeding have ensured that the rates of MTCT remain low in Malaysia. This review discusses the most recent advances in the management of HIV infection in pregnancy with emphasis on antiretroviral treatment strategies and obstetric care in a middle income country.

Transmission of Guanarito and Pirital Viruses among Wild Rodents, Venezuela

Science.gov (United States)

Milazzo, Mary L.; Cajimat, Maria N.B.; Duno, Gloria; Duno, Freddy; Utrera, Antonio

2011-01-01

Samples from rodents captured on a farm in Venezuela in February 1997 were tested for arenavirus, antibody against Guanarito virus (GTOV), and antibody against Pirital virus (PIRV). Thirty-one (48.4%) of 64 short-tailed cane mice (Zygodontomys brevicauda) were infected with GTOV, 1 Alston’s cotton rat (Sigmodon alstoni) was infected with GTOV, and 36 (64.3%) of 56 other Alston’s cotton rats were infected with PIRV. The results of analyses of field and laboratory data suggested that horizontal transmission is the dominant mode of GTOV transmission in Z. brevicauda mice and that vertical transmission is an important mode of PIRV transmission in S. alstoni rats. The results also suggested that bodily secretions and excretions from most GTOV-infected short-tailed cane mice and most PIRV-infected Alston’s cotton rats may transmit the viruses to humans. PMID:22172205

Single-mode 850-nm vertical-cavity surface-emitting lasers with Zn-diffusion and oxide-relief apertures for > 50 Gbit/sec OOK and 4-PAM transmission

Science.gov (United States)

Shi, Jin-Wei; Wei, Chia-Chien; Chen, Jyehong; Ledentsov, N. N.; Yang, Ying-Jay

2017-02-01

Vertical-cavity surface-emitting lasers (VCSELs) has become the most important light source in the booming market of short-reach (targeted at 56 Gbit/sec data rate per channel (CEI-56G) with the total data rate up to 400 Gbit/sec. However, the serious modal dispersion of multi-mode fiber (MMF), limited speed of VCSEL, and its high resistance (> 150 Ω) seriously limits the >50 Gbit/sec linking distance (50 Gbit/sec transmission due to that it can save one-half of the required bandwidth. Nevertheless, a 4.7 dB optical power penalty and the linearity of transmitter would become issues in the 4-PAM linking performance. Besides, in the modern OI system, the optics transreceiver module must be packaged as close as possible with the integrated circuits (ICs). The heat generated from ICs will become an issue in speed of VSCEL. Here, we review our recent work about 850 nm VCSEL, which has unique Zn-diffusion/oxide-relief apertures and special p- doping active layer with strong wavelength detuning to further enhance its modulation speed and high-temperature (85°C) performances. Single-mode (SM) devices with high-speed ( 26 GHz), reasonable resistance ( 70 Ω) and moderate output power ( 1.5 mW) can be achieved. Error-free 54 Gbit/sec OOK transmission through 1km MMF has been realized by using such SM device with signal processing techniques. Besides, the volterra nonlinear equalizer has been applied in our 4-PAM 64 Gbit/sec transmission through 2-km OM4 MMF, which significantly enhance the linearity of device and outperforms fed forward equalization (FFE) technique. Record high bit-rate distance product of 128.km is confirmed for optical-interconnect applications.

Elephant-to-Human Transmission of Tuberculosis

Centers for Disease Control (CDC) Podcasts

2011-02-23

This podcast reports on the transmission of TB from elephants to humans. Dr. Rendi Murphree, Epidemic Intelligence Service Officer at the Centers for Disease Control and Prevention and Vanderbilt University Visiting Scholar, discusses the recent elephant-to-human transmission of tuberculosis at an elephant refuge in Tennessee.  Created: 2/23/2011 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/23/2011.

Prevention of mother-to-child transmission in HIV audit in Xhosa clinic, Mahalapye, Botswana

Directory of Open Access Journals (Sweden)

Stephane Tshitenge

2014-01-01

Full Text Available Background: The Mahalapye district health management team (DHMT conducts regular audits to evaluate the standard of services delivered to patients, one of which is the prevention of mother-to-child-transmission (PMTCT programme. Xhosa clinic is one of the facilities in Mahalapye which provides a PMTCT programme.Aim: This audit aimed to identify gaps between the current PMTCT clinical practice in Xhosa clinic and the Botswana PMTCT national guidelines.Setting: This audit took place in Xhosa clinic in the urban village of Mahalapye, in the Central District of Botswana.Methods: This was a retrospective audit using PMTCT Xhosa clinic records of pregnant mothers and HIV-exposed babies seen from January 2013 to June 2013.Results: One hundred and thirty-three pregnant women registered for antenatal care. Twenty-five (19% knew their HIV-positive status as they had been tested before their pregnancy or had tested HIV positive at their first antenatal clinic visit. More than two-thirds of the 115 pregnant women (69% were seen at a gestational age of between 14 and 28 weeks. About two-thirds of the pregnant women (67% took antiretroviral drugs. Of the 44 HIV-exposed infants, 39 (89% were HIV DNA PCR negative at 6 weeks. Thirty-two (73% children were given cotrimoxazole prophylaxis between 6 and 8 weeks.Conclusion: The PMTCT programme service delivery was still suboptimal and could potentially increase the mother-to-child transmission of HIV. Daily monitoring mechanism to track those eligible could help to close the gap.

Preventing Airborne Disease Transmission: Review of Methods for Ventilation Design in Health Care Facilities

Science.gov (United States)

Aliabadi, Amir A.; Rogak, Steven N.; Bartlett, Karen H.; Green, Sheldon I.

2011-01-01

Health care facility ventilation design greatly affects disease transmission by aerosols. The desire to control infection in hospitals and at the same time to reduce their carbon footprint motivates the use of unconventional solutions for building design and associated control measures. This paper considers indoor sources and types of infectious aerosols, and pathogen viability and infectivity behaviors in response to environmental conditions. Aerosol dispersion, heat and mass transfer, deposition in the respiratory tract, and infection mechanisms are discussed, with an emphasis on experimental and modeling approaches. Key building design parameters are described that include types of ventilation systems (mixing, displacement, natural and hybrid), air exchange rate, temperature and relative humidity, air flow distribution structure, occupancy, engineered disinfection of air (filtration and UV radiation), and architectural programming (source and activity management) for health care facilities. The paper describes major findings and suggests future research needs in methods for ventilation design of health care facilities to prevent airborne infection risk. PMID:22162813

Illumination of murine gammaherpesvirus-68 cycle reveals a sexual transmission route from females to males in laboratory mice.

Directory of Open Access Journals (Sweden)

Sylvie François

Full Text Available Transmission is a matter of life or death for pathogen lineages and can therefore be considered as the main motor of their evolution. Gammaherpesviruses are archetypal pathogenic persistent viruses which have evolved to be transmitted in presence of specific immune response. Identifying their mode of transmission and their mechanisms of immune evasion is therefore essential to develop prophylactic and therapeutic strategies against these infections. As the known human gammaherpesviruses, Epstein-Barr virus and Kaposi's Sarcoma-associated Herpesvirus are host-specific and lack a convenient in vivo infection model; related animal gammaherpesviruses, such as murine gammaherpesvirus-68 (MHV-68, are commonly used as general models of gammaherpesvirus infections in vivo. To date, it has however never been possible to monitor viral excretion or virus transmission of MHV-68 in laboratory mice population. In this study, we have used MHV-68 associated with global luciferase imaging to investigate potential excretion sites of this virus in laboratory mice. This allowed us to identify a genital excretion site of MHV-68 following intranasal infection and latency establishment in female mice. This excretion occurred at the external border of the vagina and was dependent on the presence of estrogens. However, MHV-68 vaginal excretion was not associated with vertical transmission to the litter or with horizontal transmission to female mice. In contrast, we observed efficient virus transmission to naïve males after sexual contact. In vivo imaging allowed us to show that MHV-68 firstly replicated in penis epithelium and corpus cavernosum before spreading to draining lymph nodes and spleen. All together, those results revealed the first experimental transmission model for MHV-68 in laboratory mice. In the future, this model could help us to better understand the biology of gammaherpesviruses and could also allow the development of strategies that could prevent

Transmission of electric dipole radiation through an interface

Energy Technology Data Exchange (ETDEWEB)

Arnoldus, Henk F., E-mail: hfa1@msstate.edu [Department of Physics and Astronomy, Mississippi State University, P.O. Drawer 5167, Mississippi State, MS 39762-5167 (United States); Berg, Matthew J., E-mail: matt.berg@msstate.edu [Department of Physics and Astronomy, Mississippi State University, P.O. Drawer 5167, Mississippi State, MS 39762-5167 (United States); Li, Xin, E-mail: Xin.Li@millersville.edu [Department of Physics, P.O. Box 1002, Millersville University, Millersville, PA 17551 (United States)

2014-02-07

We consider the transmission of electric dipole radiation through an interface between two dielectrics, for the case of a vertical dipole. Energy flows along the field lines of the Poynting vector, and in the optical near field these field lines are curves (as opposed to optical rays). When the radiation passes through the interface into a thicker medium, the field lines bend to the normal (as rays do), but the transmission angle is not related to the angle of incidence. The redirection of the radiation at the interface is determined by the angle dependence of the transmission coefficient. This near-field redistribution is responsible for the far-field angular power pattern. When the transmission medium is thinner than the embedding medium of the dipole, some energy flows back and forth through the interface in an oscillating fashion. In each area where field lines dip below the interface, an optical vortex appears just above the interface. The centers of these vortices are concentric singular circles around the dipole axis.

Designing and Evaluating Interventions to Halt the Transmission of Tuberculosis.

Science.gov (United States)

Dowdy, David W; Grant, Alison D; Dheda, Keertan; Nardell, Edward; Fielding, Katherine; Moore, David A J

2017-11-03

To reduce the incidence of tuberculosis, it is insufficient to simply understand the dynamics of tuberculosis transmission. Rather, we must design and rigorously evaluate interventions to halt transmission, prioritizing those interventions most likely to achieve population-level impact. Synergy in reducing tuberculosis transmission may be attainable by combining interventions that shrink the reservoir of latent Mycobacterium tuberculosis infection (preventive therapy), shorten the time between disease onset and treatment initiation (case finding and diagnosis), and prevent transmission in key settings, such as the built environment (infection control). In evaluating efficacy and estimating population-level impact, cluster-randomized trials and mechanistic models play particularly prominent roles. Historical and contemporary evidence suggests that effective public health interventions can halt tuberculosis transmission, but an evidence-based approach based on knowledge of local epidemiology is necessary for success. We provide a roadmap for designing, evaluating, and modeling interventions to interrupt the process of transmission that fuels a diverse array of tuberculosis epidemics worldwide. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Advanced Si solid phase crystallization for vertical channel in vertical NANDs

Directory of Open Access Journals (Sweden)

Sangsoo Lee

2014-07-01

Full Text Available The advanced solid phase crystallization (SPC method using the SiGe/Si bi-layer structure is proposed to obtain high-mobility poly-Si thin-film transistors in next generation vertical NAND (VNAND devices. During the SPC process, the top SiGe thin film acts as a selective nucleation layer to induce surface nucleation and equiaxial microstructure. Subsequently, this SiGe thin film microstructure is propagated to the underlying Si thin film by epitaxy-like growth. The initial nucleation at the SiGe surface was clearly observed by in situ transmission electron microscopy (TEM when heating up to 600 °C. The equiaxial microstructures of both SiGe nucleation and Si channel layers were shown in the crystallized bi-layer plan-view TEM measurements. Based on these experimental results, the large-grained and less-defective Si microstructure is expected to form near the channel region of each VNAND cell transistor, which may improve the electrical characteristics.

Active Low-frequency Vertical Vibration Isolation System for Precision Measurements

Institute of Scientific and Technical Information of China (English)

WU Kang; LI Gang; HU Hua; WANG Lijun

2017-01-01

Low-frequency vertical vibration isolation systems play important roles in precision measurements to reduce seismic and environmental vibration noise.Several types of active vibration isolation systems have been developed.However,few researches focus on how to optimize the test mass install position in order to improve the vibration transmissibility.An active low-frequency vertical vibration isolation system based on an earlier instrument,the Super Spring,is designed and implemented.The system,which is simple and compact,consists of two stages:a parallelogram-shaped linkage to ensure vertical motion,and a simple spring-mass system.The theoretical analysis of the vibration isolation system is presented,including terms erroneously ignored before.By carefully choosing the mechanical parameters according to the above analysis and using feedback control,the resonance frequency of the system is reduced from 2.3 to 0.03 Hz,a reduction by a factor of more than 75.The vibration isolation system is installed as an inertial reference in an absolute gravimeter,where it improved the scatter of the absolute gravity values by a factor of 5.The experimental results verifies the improved performance of the isolation system,making it particularly suitable for precision experiments.The improved vertical vibration isolation system can be used as a prototype for designing high-performance active vertical isolation systems.An improved theoretical model of this active vibration isolation system with beam-pivot configuration is proposed,providing fundamental guidelines for vibration isolator design and assembling.

Role of the carbohydrate-binding sites of griffithsin in the prevention of DC-SIGN-mediated capture and transmission of HIV-1.

Directory of Open Access Journals (Sweden)

Bart Hoorelbeke

Full Text Available BACKGROUND: The glycan-targeting C-type DC-SIGN lectin receptor is implicated in the transmission of the human immunodeficiency virus (HIV by binding the virus and transferring the captured HIV-1 to CD4(+ T lymphocytes. Carbohydrate binding agents (CBAs have been reported to block HIV-1 infection. We have now investigated the potent mannose-specific anti-HIV CBA griffithsin (GRFT on its ability to inhibit the capture of HIV-1 to DC-SIGN, its DC-SIGN-directed transmission to CD4(+ T-lymphocytes and the role of the three carbohydrate-binding sites (CBS of GRFT in these processes. FINDINGS: GRFT inhibited HIV-1(IIIB infection of CEM and HIV-1(NL4.3 infection of C8166 CD4(+ T-lymphocytes at an EC50 of 0.059 and 0.444 nM, respectively. The single mutant CBS variants of GRFT (in which a key Asp in one of the CBS was mutated to Ala were about ∼20 to 60-fold less potent to prevent HIV-1 infection and ∼20 to 90-fold less potent to inhibit syncytia formation in co-cultures of persistently HIV-1 infected HuT-78 and uninfected C8166 CD4(+ T-lymphocytes. GRFT prevents DC-SIGN-mediated virus capture and HIV-1 transmission to CD4(+ T-lymphocytes at an EC50 of 1.5 nM and 0.012 nM, respectively. Surface plasmon resonance (SPR studies revealed that wild-type GRFT efficiently blocked the binding between DC-SIGN and immobilized gp120, whereas the point mutant CBS variants of GRFT were ∼10- to 15-fold less efficient. SPR-analysis also demonstrated that wild-type GRFT and its single mutant CBS variants have the capacity to expel bound gp120 from the gp120-DC-SIGN complex in a dose dependent manner, a property that was not observed for HHA, another mannose-specific potent anti-HIV-1 CBA. CONCLUSION: GRFT is inhibitory against HIV gp120 binding to DC-SIGN, efficiently prevents DC-SIGN-mediated transfer of HIV-1 to CD4(+ T-lymphocytes and is able to expel gp120 from the gp120-DC-SIGN complex. Functionally intact CBS of GRFT are important for the optimal action of

Transmission of the gut microbiota: spreading of health

Science.gov (United States)

Browne, Hilary P.; Neville, B. Anne; Forster, Samuel C.; Lawley, Trevor D.

2018-01-01

Transmission of commensal intestinal bacteria between humans could promote health by establishing, maintaining and replenishing microbial diversity in the microbiota of an individual. Unlike pathogens, the routes of transmission for commensal bacteria remain unappreciated and poorly understood, despite the likely commonalities between both. Consequently, broad infection control measures that are designed to prevent pathogen transmission and infection, such as oversanitation and the overuse of antibiotics, may inadvertently affect human health by altering normal commensal transmission. In this Review, we discuss the mechanisms and factors that influence host-to-host transmission of the intestinal microbiota and examine how a better understanding of these processes will identify new approaches to nurture and restore transmission routes that are used by beneficial bacteria. PMID:28603278

Reuse of single-dose nevirapine in subsequent pregnancies for the prevention of mother-to-child HIV transmission in Lusaka, Zambia: A cohort study

Directory of Open Access Journals (Sweden)

Sinkala Moses

2008-12-01

Full Text Available Abstract Background Single-dose nevirapine (SDNVP for the prevention of mother-to-child HIV transmission (PMTCT results in the selection of resistance mutants among HIV-infected mothers. The effects of these mutations on the efficacy of SDNVP use in a subsequent pregnancy are not well understood. Methods We compared risks of perinatal HIV transmission between multiparous women who had previously received a dose of SDNVP (exposed and those that had not (unexposed and who were given SDNVP for the index pregnancy within a PMTCT clinical study. We also compared transmission risks among exposed and unexposed women who had two consecutive pregnancies within the trial. Logistic regression modeling was used to adjust for possible confounders. Results Transmission risks did not differ between 59 SDNVP-exposed and 782 unexposed women in unadjusted analysis or after adjustment for viral load and disease stage (adjusted odds ratio 0.6, 95% confidence interval [CI] 0.2 to 2.0. Among 43 women who had two consecutive pregnancies during the study, transmission risks were 7% (95% CI 1% to 19% at both the first (unexposed and second (exposed delivery. The results were unchanged, if infant death was included as an outcome. Conclusion These data suggest that the efficacy of SDNVP may not be diminished when reused in subsequent pregnancies.

Cost-effectiveness of antiviral therapy during late pregnancy to prevent perinatal transmission of hepatitis B virus

Directory of Open Access Journals (Sweden)

Wenjun Wang

2016-03-01

Full Text Available Background. Hepatitis B virus (HBV infections are perinatally transmitted from chronically infected mothers. Supplemental antiviral therapy during late pregnancy with lamivudine (LAM, telbivudine (LdT, or tenofovir (TDF can substantially reduce perinatal HBV transmission compared to postnatal immunoprophylaxis (IP alone. However, the cost-effectiveness of these measures is not clear. Aim. This study evaluated the cost-effectiveness from a societal perspective of supplemental antiviral agents for preventing perinatal HBV transmission in mothers with high viral load (>6 log10 copies/mL. Methods. A systematic review and network meta-analysis were performed for the risk of perinatal HBV transmission with antiviral therapies. A decision analysis was conducted to evaluate the clinical and economic outcomes in China of four competing strategies: postnatal IP alone (strategy IP, or in combination with perinatal LAM (strategy LAM + IP, LdT (strategy LdT + IP, or TDF (strategy TDF + IP. Antiviral treatments were administered from week 28 of gestation to 4 weeks after birth. Outcomes included treatment-related costs, number of infections, and quality-adjusted life years (QALYs. One- and two-way sensitivity analyses were performed to identify influential clinical and cost-related variables. Probabilistic sensitivity analyses were used to estimate the probabilities of being cost-effective for each strategy. Results. LdT + IP and TDF + IP averted the most infections and HBV-related deaths, and gained the most QALYs. IP and TDF + IP were dominated as they resulted in less or equal QALYs with higher associated costs. LdT + IP had an incremental $2,891 per QALY gained (95% CI [$932–$20,372] compared to LAM + IP (GDP per capita for China in 2013 was $6,800. One-way sensitivity analyses showed that the cost-effectiveness of LdT + IP was only sensitive to the relative risk of HBV transmission comparing LdT + IP with LAM + IP. Probabilistic sensitivity analyses

Towards effective interventions for transgender people and their clients to prevent HIV infection and transmission : A study of the psychological determinants, sexual behavior s, and socio-demographic characteristics related to condom use and health care use

NARCIS (Netherlands)

Prabawanti, Ciptasari

2015-01-01

In Indonesia, transgender people (waria) have the second highest HIV prevalence (21.9%), the first being people who inject drugs (36.4%). To reduce HIV incidence among transgender people and prevent HIV transmission, they should have access to all prevention services including education, prevention

Outcome of Prevention of Parent-to-Child Transmission of HIV in an Urban Population in Southern India.

Science.gov (United States)

Seenivasan, Subramani; Vaitheeswaran, Natarajan; Seetha, Viswanathan; Anbalagan, Selvaraj; Karunaianantham, Ramesh; Swaminathan, Soumya

2015-09-01

To analyze the outcomes of Prevention of Parent to Child Transmission (PPTCT) of HIV program in an urban Southern Indian setting. Observational study. Anti-retroviral Therapy (ART) Centers/ Integrated Counseling and Testing Centers (ICTC) at four government Obstetrics Institutes in an urban area. 100 HIV-positive pregnant women and their infants delivered in the study centers. Triple drug ART to HIV-positive pregnant women was started for maternal indications only. Rest of the pregnant women were given single dose Nevirapine (200 mg) at the onset of labor. All infants were given single dose Nevirapine (2 mg/kg) prophylaxis, according to National AIDS Control Organization guidelines. Mothers were counseled regarding breastfeeding and artificial feeding, and the choice was left to them. Whole blood HIV 1 DNA PCR was done for all infants at 6 weeks of life. A second PCR was done at 6 months or 6 weeks after stopping breastfeeds. PCR-positive infants were started on ART, and were followed-up till18 months of life. Four infants were PCR-positive for HIV. All of them were breastfed. They were born to mothers of HIV stage 1 or 2 who were not on ART as CD4 counts were >350 cells/mm3. Among the mothers in Stage 3 or 4 or CD4 count ART, none of the infants was HIV-positive. The cumulative HIV-free survival at 18 months was 94%. Parent-to-child transmission rate in HIV was low with the currently used strategies. Triple drug ART to mother reduces mother-to-child transmission despite advanced maternal stage or low CD4 counts.

HIV rapid testing as a key strategy for prevention of mother-to-child transmission in Brazil Prueba rápida para el HIV como una estrategia para la prevención de la transmisión vertical en Brasil Teste rápido para o HIV como estratégia de prevenção da transmissão vertical no Brasil

Directory of Open Access Journals (Sweden)

Valdiléa G Veloso

2010-10-01

de Janeiro (4/47 y en seis casos en Porto Alegre (6/79. CONCLUSIONES: La estrategia se mostró factible en las maternidades de Rio de Janeiro y de Porto Alegre. Esfuerzos deben ser emprendidos para maximizar la evaluación durante el trabajo de parto. Fuerte soporte social precisa ser acoplado a esa estrategia para garantizar el acceso de dicha población al sistema de salud posterior a ser dado de alta de la maternidad.OBJETIVO: Analisar a viabilidade da testagem rápida para o HIV entre gestantes na admissão à maternidade e de intervenções para reduzir a transmissão perinatal do HIV. MÉTODOS: Amostra de conveniência de mulheres que desconheciam sua situação sorológica para o HIV quando admitidas para o parto em maternidades públicas do Rio de Janeiro, RJ, e de Porto Alegre, RS, entre março de 2000 e abril de 2002. As mulheres foram aconselhadas e testadas com teste rápido Determine HIV1/2 na maternidade. Infecção pelo HIV foi confirmada pelo algoritmo brasileiro para o diagnóstico da infecção pelo HIV. A transmissão intra-útero foi determinada pelo PCR-DNA-HIV. Foram realizadas análises descritivas dos dados sociodemográficos, número de gestações e de abortos prévios, número de visitas de pré-natal, momento da testagem para o HIV, resultado do teste rápido para o HIV, intervenções recebidas pelos recém-natos e de transmissão vertical do HIV, de acordo com cada cidade. RESULTADOS: A prevalência de HIV entre as mulheres foi 6,5% (N=1.439 em Porto Alegre e 1,3% (N=3.778 no Rio de Janeiro. A maioria foi testada durante o trabalho de parto em Porto Alegre e no pós-parto, no Rio de Janeiro. Cento e quarenta e quatro crianças nasceram de 143 mulheres infectadas pelo HIV. Todos os recém-natos receberam ao menos a profilaxia com zidovudina oral, exceto um em cada cidade. Foi possível evitar qualquer exposição ao leite materno em 96,8% e 51,1% dos recém-natos em Porto Alegre e no Rio de Janeiro, respectivamente. A zidovudina injet

Dam-to-offspring transmission and persistence of Staphylococcus pseudintermedius clones within dog families

DEFF Research Database (Denmark)

Paul, Narayan Chandra; Damborg, Peter Panduro; Guardabassi, Luca

2014-01-01

Staphylococcus pseudintermedius is an opportunistic pathogen that causes mainly skin infections in dogs. Although vertical transmission of S. pseudintermedius strains from dam to offspring has been reported, the persistence of the dam's strains in offspring over long periods of time is virtually ...

Stigma as experienced by women accessing prevention of parent to child transmission of HIV services in Karnataka, India

Science.gov (United States)

Rahangdale, Lisa; Banandur, Pradeep; Sreenivas, Amita; Turan, Janet; Washington, Reynold; Cohen, Craig R.

2010-01-01

In Karnataka, India only one-third of HIV-infected pregnant women received antiretroviral prophylaxis at delivery in 2007 through the state government’s prevention of parent-to-child HIV transmission (PPTCT) program. The current qualitative study explored the role of HIV-associated stigma as a barrier to accessing PPTCT services in the rural northern Karnataka district of Bagalkot using in depth interviews and focus group discussions with HIV-infected women who had participated in the PPTCT program, male and female family members, and HIV service providers. Participants discussed personal experiences, community perceptions of HIV, and decision-making related to accessing PPTCT services. They described stigma towards HIV-infected individuals from multiple sources: healthcare workers, community members, family and self. Stigma-related behaviors were based on fears of HIV transmission through personal contact and moral judgment. Experience and/or fears of discrimination led pregnant women to avoid using PPTCT interventions. Government, cultural and historical factors are described as the roots of much the stigma-related behavior in this setting. Based on these formative data, PPTCT program planners should consider further research and interventions aimed at diminishing institutional and interpersonal HIV-associated stigma experienced by pregnant women. PMID:20635247

Interventions to significantly improve service uptake and retention of HIV-positive pregnant women and HIV-exposed infants along the prevention of mother-to-child transmission continuum of care: systematic review.

Science.gov (United States)

Vrazo, Alexandra C; Firth, Jacqueline; Amzel, Anouk; Sedillo, Rebecca; Ryan, Julia; Phelps, B Ryan

2018-02-01

Despite the success of Prevention of Mother-to-Child Transmission of HIV (PMTCT) programmes, low uptake of services and poor retention pose a formidable challenge to achieving the elimination of vertical HIV transmission in low- and middle-income countries. This systematic review summarises interventions that demonstrate statistically significant improvements in service uptake and retention of HIV-positive pregnant and breastfeeding women and their infants along the PMTCT cascade. Databases were systematically searched for peer-reviewed studies. Outcomes of interest included uptake of services, such as antiretroviral therapy (ART) such as initiation, early infant diagnostic testing, and retention of HIV-positive pregnant and breastfeeding women and their infants. Interventions that led to statistically significant outcomes were included and mapped to the PMTCT cascade. An eight-item assessment tool assessed study rigour. CRD42017063816. Of 686 citations reviewed, 11 articles met inclusion criteria. Ten studies detailed maternal outcomes and seven studies detailed infant outcomes in PMTCT programmes. Interventions to increase access to antenatal care (ANC) and ART services (n = 4) and those using lay cadres (n = 3) were most common. Other interventions included quality improvement (n = 2), mHealth (n = 1), and counselling (n = 1). One study described interventions in an Option B+ programme. Limitations included lack of HIV testing and counselling and viral load monitoring outcomes, small sample size, geographical location, and non-randomized assignment and selection of participants. Interventions including ANC/ART integration, family-centred approaches, and the use of lay healthcare providers are demonstrably effective in increasing service uptake and retention of HIV-positive mothers and their infants in PMTCT programmes. Future studies should include control groups and assess whether interventions developed in the context of earlier 'Options' are

Transmission-Blocking Antibodies against Mosquito C-Type Lectins for Dengue Prevention

Science.gov (United States)

Liu, Yang; Zhang, Fuchun; Liu, Jianying; Xiao, Xiaoping; Zhang, Siyin; Qin, Chengfeng; Xiang, Ye; Wang, Penghua; Cheng, Gong

2014-01-01

C-type lectins are a family of proteins with carbohydrate-binding activity. Several C-type lectins in mammals or arthropods are employed as receptors or attachment factors to facilitate flavivirus invasion. We previously identified a C-type lectin in Aedes aegypti, designated as mosquito galactose specific C-type lectin-1 (mosGCTL-1), facilitating the attachment of West Nile virus (WNV) on the cell membrane. Here, we first identified that 9 A. aegypti mosGCTL genes were key susceptibility factors facilitating DENV-2 infection, of which mosGCTL-3 exhibited the most significant effect. We found that mosGCTL-3 was induced in mosquito tissues with DENV-2 infection, and that the protein interacted with DENV-2 surface envelop (E) protein and virions in vitro and in vivo. In addition, the other identified mosGCTLs interacted with the DENV-2 E protein, indicating that DENV may employ multiple mosGCTLs as ligands to promote the infection of vectors. The vectorial susceptibility factors that facilitate pathogen invasion may potentially be explored as a target to disrupt the acquisition of microbes from the vertebrate host. Indeed, membrane blood feeding of antisera against mosGCTLs dramatically reduced mosquito infective ratio. Hence, the immunization against mosGCTLs is a feasible approach for preventing dengue infection. Our study provides a future avenue for developing a transmission-blocking vaccine that interrupts the life cycle of dengue virus and reduces disease burden. PMID:24550728

Algebraic motion of vertically displacing plasmas

Science.gov (United States)

Pfefferlé, D.; Bhattacharjee, A.

2018-02-01

The vertical motion of a tokamak plasma is analytically modelled during its non-linear phase by a free-moving current-carrying rod inductively coupled to a set of fixed conducting wires or a cylindrical conducting shell. The solutions capture the leading term in a Taylor expansion of the Green's function for the interaction between the plasma column and the surrounding vacuum vessel. The plasma shape and profiles are assumed not to vary during the vertical drifting phase such that the plasma column behaves as a rigid body. In the limit of perfectly conducting structures, the plasma is prevented to come in contact with the wall due to steep effective potential barriers created by the induced Eddy currents. Resistivity in the wall allows the equilibrium point to drift towards the vessel on the slow timescale of flux penetration. The initial exponential motion of the plasma, understood as a resistive vertical instability, is succeeded by a non-linear "sinking" behaviour shown to be algebraic and decelerating. The acceleration of the plasma column often observed in experiments is thus concluded to originate from an early sharing of toroidal current between the core, the halo plasma, and the wall or from the thermal quench dynamics precipitating loss of plasma current.

Perceptions and behaviors related to hand hygiene for the prevention of H1N1 influenza transmission among Korean university students during the peak pandemic period

Directory of Open Access Journals (Sweden)

Kim Seon-Ung

2010-07-01

Full Text Available Abstract Background This study was performed to better assess the perceptions, motivating factors, and behaviors associated with the use of hand washing to prevent H1N1 influenza transmission during the peak pandemic period in Korea. Methods A cross-sectional survey questionnaire was completed by 942 students at a university campus in Suwon, Korea, between December 1 and 8, 2009. The survey included questions regarding individual perceptions, motivating factors, and behaviors associated with hand washing for the prevention of H1N1 influenza transmission. Results Compared to one year prior, 30.3% of participants reported increasing their hand washing frequency. Female students were more likely to practice more frequent hand washing. Women also perceived the effectiveness of hand washing to be lower, and illness severity and personal susceptibility to H1N1 infection to be higher. Study participants who were female (OR: 1.79-3.90 who perceived of hand washing to be effective (OR: 1.34-12.15 and illness severity to be greater (OR: 1.00-3.12 washed their hands more frequently. Conclusions Korean students increased their frequency of hand hygiene practices during the pandemic, with significant gender differences existing in the attitudes and behaviors related to the use of hand hygiene as a means of disease prevention. Here, the factors that affected hand washing behavior were similar to those identified at the beginning of the H1N1 or SARS pandemics, suggesting that public education campaigns regarding hand hygiene are effective in altering individual hand hygiene habits during the peak periods of influenza transmission.

Vertical blind phase search for low-complexity carrier phase recovery of offset-QAM Nyquist WDM transmission

Science.gov (United States)

Lu, Jianing; Fu, Songnian; Tang, Haoyuan; Xiang, Meng; Tang, Ming; Liu, Deming

2017-01-01

Low complexity carrier phase recovery (CPR) scheme based on vertical blind phase search (V-BPS) for M-ary offset quadrature amplitude modulation (OQAM) is proposed and numerically verified. After investigating the constellations of both even and odd samples with respect to the phase noise, we identify that the CPR can be realized by measuring the verticality of constellation with respect to different test phase angles. Then measurement without multiplication in the complex plane is found with low complexity. Furthermore, a two-stage configuration is put forward to further reduce the computational complexity (CC). Compared with our recently proposed modified blind phase search (M-BPS) algorithm, the proposed algorithm shows comparable tolerance of phase noise, but reduces the CC by a factor of 3.81 (or 3.05) in the form of multipliers (or adders), taking the CPR of 16-OQAM into account.

Prevention de la transmission mere enfant du VIH/SIDA au Chu de ...

African Journals Online (AJOL)

La transmission Mère Enfant du VIH/SIDA est le mode de contamination essentielle des enfants dans les pays en développement. Objectif : Evaluer les résultats de la Prévention de la Transmission Mère-Enfant (PTME) du VIH au CHU-Kara. Méthode: Il s'est agi d'une étude rétrospective descriptive de juillet 2005 à Juin ...

The role of the ratio of vector and host densities in the evolution of transmission modes in vector-borne diseases. The example of sylvatic Trypanosoma cruzi.

Science.gov (United States)

Pelosse, Perrine; Kribs-Zaleta, Christopher M

2012-11-07

Pathogens may use different routes of transmission to maximize their spread among host populations. Theoretical and empirical work conducted on directly transmitted diseases suggest that horizontal (i.e., through host contacts) and vertical (i.e., from mother to offspring) transmission modes trade off, on the ground that highly virulent pathogens, which produce larger parasite loads, are more efficiently transmitted horizontally, and that less virulent pathogens, which impair host fitness less significantly, are better transmitted vertically. Other factors than virulence such as host density could also select for different transmission modes, but they have barely been studied. In vector-borne diseases, pathogen transmission rate is strongly affected by host-vector relative densities and by processes of saturation in contacts between hosts and vectors. The parasite Trypanosoma cruzi which is transmitted by triatomine bugs to several vertebrate hosts is responsible for Chagas' disease in Latin America. It is also widespread in sylvatic cycles in the southeastern U.S. in which it typically induces no mortality costs to its customary hosts. Besides classical transmission via vector bites, alternative ways to generate infections in hosts such as vertical and oral transmission (via the consumption of vectors by hosts) have been reported in these cycles. The two major T. cruzi strains occurring in the U.S. seem to exhibit differential efficiencies at vertical and classical horizontal transmissions. We investigated whether the vector-host ratio affects the outcome of the competition between the two parasite strains using an epidemiological two-strain model considering all possible transmission routes for sylvatic T. cruzi. We were able to show that the vector-host ratio influences the evolution of transmission modes providing that oral transmission is included in the model as a possible transmission mode, that oral and classical transmissions saturate at different vector

47 CFR 73.646 - Telecommunications Service on the Vertical Blanking Interval and in the Visual Signal.

Science.gov (United States)

2010-10-01

... Blanking Interval and in the Visual Signal. 73.646 Section 73.646 Telecommunication FEDERAL COMMUNICATIONS... transmission of data, processed information, or any other communication in either a digital or analog mode. (b....646 Telecommunications Service on the Vertical Blanking Interval and in the Visual Signal. (a...

Ecological patterns of seed microbiome diversity, transmission, and assembly.

Science.gov (United States)

Shade, Ashley; Jacques, Marie-Agnès; Barret, Matthieu

2017-06-01

Seeds are involved in the transmission of microorganisms from one plant generation to another and consequently act as the initial inoculum for the plant microbiota. The purpose of this mini-review is to provide an overview of current knowledge on the diversity, structure and role of the seed microbiota. The relative importance of the mode of transmission (vertical vs horizontal) of the microbial entities composing the seed microbiota as well as the potential connections existing between seed and other plant habitats such as the anthosphere and the spermosphere is discussed. Finally the governing processes (niche vs neutral) involved in the assembly and the dynamics of the seed microbiota are examined. Copyright © 2017. Published by Elsevier Ltd.

Frequency and factors associated with adherence to and completion of combination antiretroviral therapy for prevention of mother to child transmission in western Kenya

OpenAIRE

Ayuo, Paul; Musick, Beverly; Liu, Hai; Braitstein, Paula; Nyandiko, Winstone; Otieno-Nyunya, Boaz; Gardner, Adrian; Wools-Kaloustian, Kara

2013-01-01

Introduction: The objective of this analysis was to identify points of disruption within the prevention of mother-to-child transmission (PMTCT) continuum from combination antiretroviral therapy (CART) initiation until delivery. Methods: To address this objective, the electronic medical records of all antiretroviral-naïve adult pregnant women who were initiating CART for PMTCT between January 2006 and February 2009 within the Academic Model Providing Access To Healthcare (AMPATH), weste...

Hepatitis C virus infection among transmission-prone medical personnel

NARCIS (Netherlands)

Zaaijer, H. L.; Appelman, P.; Frijstein, G.

2012-01-01

Hepatitis C virus (HCV)-infected physicians have been reported to infect some of their patients during exposure-prone procedures (EPPs). There is no European consensus on the policy for the prevention of this transmission. To help define an appropriate preventive policy, we determined the prevalence

Integration of prevention of mother-to-child HIV transmission into maternal health services in Senegal.

Science.gov (United States)

Cisse, C

2017-06-01

The objective of this study was to assess the level of integration of prevention of mother-to-child HIV transmission (PMTCT) in facilities providing services for maternal, newborn, and child health (MNCH) and reproductive health (RH) in Senegal. The survey, conducted from August through November, 2014, comprised five parts : a literature review to assess the place of this integration in the health policies, standards, and protocols in effect in Senegal; an analysis by direct observation of attitudes and practices of 25 healthcare providers at 5 randomly-selected obstetrics and gynecology departments representative of different levels of the health pyramid; a questionnaire evaluating knowledge and attitudes of 10 providers about the integration of PMTCT services into MNCH/RH facilities; interviews to collect the opinions of 70 clients, including 16 HIV-positive, about the quality of PMTCT services they received; and a questionnaire evaluating knowledge and opinions of 14 policy-makers/managers of health programs focusing on mothers and children about this integration. The literature review revealed several constraints impeding this integration : the policy documents, standards, and protocols of each of the programs involved do not clearly indicate the modalities of this integration; the programs are housed in two different divisions while the national Program against the Human Immunodeficiency Virus reports directly to the Prime Minister; program operations remains generally vertical; the resources for the different programs are not sufficiently shared; there is no integrated training module covering integrated management of pregnancy and delivery; and supervision for each of the different programs is organized separately.The observation of the providers supporting women during pregnancy, during childbirth, and in the postpartum period, showed an effort to integrate PMTCT into the MNCH/RH services delivered daily to clients. But this desire is hampered by many

Protocol: Transmission and prevention of influenza in Hutterites: Zoonotic transmission of influenza A: swine & swine workers

Directory of Open Access Journals (Sweden)

Loeb Mark

2009-11-01

Full Text Available Abstract Background Among swine, reassortment of influenza virus genes from birds, pigs, and humans could generate influenza viruses with pandemic potential. Humans with acute infection might also be a source of infection for swine production units. This article describes the study design and methods being used to assess influenza A transmission between swine workers and pigs. We hypothesize that transmission of swine influenza viruses to humans, transmission of human influenza viruses to swine, and reassortment of human and swine influenza A viruses is occurring. The project is part of a Team Grant; all Team Grant studies include active surveillance for influenza among Hutterite swine farmers in Alberta, Canada. This project also includes non-Hutterite swine farms that are experiencing swine respiratory illness. Methods/Design Nurses conduct active surveillance for influenza-like-illness (ILI, visiting participating communally owned and operated Hutterite swine farms twice weekly. Nasopharyngeal swabs and acute and convalescent sera are obtained from persons with any two such symptoms. Swabs are tested for influenza A and B by a real time RT-PCR (reverse transcriptase polymerase chain reaction at the Alberta Provincial Laboratory for Public Health (ProvLab. Test-positive participants are advised that they have influenza. The occurrence of test-positive swine workers triggers sampling (swabbing, acute and convalescent serology of the swine herd by veterinarians. Specimens obtained from swine are couriered to St. Jude Children's Research Hospital, Memphis, TN for testing. Veterinarians and herd owners are notified if animal specimens are test-positive for influenza. If swine ILI occurs, veterinarians obtain samples from the pigs; test-positives from the animals trigger nurses to obtain specimens (swabbing, acute and convalescent serology from the swine workers. ProvLab cultures influenza virus from human specimens, freezes these cultures and

ORIGINAL ARTICLE

African Journals Online (AJOL)

boaz

... 1595-689X VOL18 No. 2. AJCEM/ 1715 http://www.ajol.info/journals/ajcem ... implementation of a mother-to-child HIV transmission prevention program as a strategy to reduce the risk of vertical transmission of the disease. Objective: To ...

DESIGN AND DEVELOPMENT OF A 1/3 SCALE VERTICAL AXIS WIND TURBINE FOR ELECTRICAL POWER GENERATION

Directory of Open Access Journals (Sweden)

Altab Md. Hossain

2007-12-01

Full Text Available This research describes the electrical power generation in Malaysia by the measurement of wind velocity acting on the wind turbine technology. The primary purpose of the measurement over the 1/3 scaled prototype vertical axis wind turbine for the wind velocity is to predict the performance of full scaled H-type vertical axis wind turbine. The electrical power produced by the wind turbine is influenced by its two major part, wind power and belt power transmission system. The blade and the drag area system are used to determine the powers of the wind that can be converted into electric power as well as the belt power transmission system. In this study both wind power and belt power transmission system has been considered. A set of blade and drag devices have been designed for the 1/3 scaled wind turbine at the Thermal Laboratory of Faculty of Engineering, Universiti Industri Selangor (UNISEL. Test has been carried out on the wind turbine with the different wind velocities of 5.89 m/s, 6.08 m/s and 7.02 m/s. From the experiment, the wind power has been calculated as 132.19 W, 145.40 W and 223.80 W. The maximum wind power is considered in the present study.

DESIGN AND DEVELOPMENT OF A 1/3 SCALE VERTICAL AXIS WIND TURBINE FOR ELECTRICAL POWER GENERATION

Directory of Open Access Journals (Sweden)

Altab Hossain

2007-01-01

Full Text Available This research describes the electrical power generation in Malaysia by the measurement of wind velocity acting on the wind turbine technology. The primary purpose of the measurement over the 1/3 scaled prototype vertical axis wind turbine for the wind velocity is to predict the performance of full scaled H-type vertical axis wind turbine. The electrical power produced by the wind turbine is influenced by its two major part, wind power and belt power transmission system. The blade and the drag area system are used to determine the powers of the wind that can be converted into electric power as well as the belt power transmission system. In this study both wind power and belt power transmission system has been considered. A set of blade and drag devices have been designed for the 1/3 scaled wind turbine at the Thermal Laboratory of Faculty of Engineering, Universiti Industri Selangor (UNISEL. Test has been carried out on the wind turbine with the different wind velocities of 5.89 m/s, 6.08 m/s and 7.02 m/s. From the experiment, the wind power has been calculated as 132.19 W, 145.40 W and 223.80 W. The maximum wind power is considered in the present study.

Microwave and Millimeter Wave Properties of Vertically-Aligned Single Wall Carbon Nanotubes Films

Science.gov (United States)

Haddadi, K.; Tripon-Canseliet, C.; Hivin, Q.; Ducournau, G.; Teo, E.; Coquet, P.; Tay, B. K.; Lepilliet, S.; Avramovic, V.; Chazelas, J.; Decoster, D.

2016-05-01

We present the experimental determination of the complex permittivity of vertically aligned single wall carbon nanotubes (SWCNTs) films grown on quartz substrates in the microwave regime from 10 MHz up to 67 GHz, with the electrical field perpendicular to the main axis of the carbon nanotubes (CNTs), based on coplanar waveguide transmission line approach together with the measurement of the microwave impedance of top metalized vertically—aligned SWCNTs grown on conductive silicon substrates up to 26 GHz. From coplanar waveguide measurements, we obtain a real part of the permittivity almost equal to unity, which is interpreted in terms of low carbon atom density (3 × 1019 at/cm3) associated with a very low imaginary part of permittivity (vertically aligned CNTs bundle equivalent to a low resistance reveals a good conductivity (3 S/cm) parallel to the CNTs axis. From these two kinds of data, we experimentally demonstrate the tensor nature of the vertically grown CNTs bundles.

Transmission of vertical stress in a real soil profile. Part II

DEFF Research Database (Denmark)

Lamandé, Mathieu; Schjønning, Per

2011-01-01

used rated tyre inflation pressures for traffic in the field (≤10 km h−1 driving speed). Seven load cells were inserted horizontally from a pit with minimal disturbance of soil at each of three depths (0.3, 0.6 and 0.9 m), covering the width of the wheeled area. The position of the wheel relative...... to the transducers was recorded using a laser sensor. Finally, the vertical stresses near the tyre–soil interface were measured in separate tests by 17 stress transducers across the width of the tyres. The level of maximum stress at 0.3 m depth was related to the surface-related stress expressions like the mean...... ground pressure and the tyre inflation pressure. The maximum stresses measured at 0.9 m depth were correlated with the wheel load (57 and 60 kPa at 60 kN load; 27 and 25 kPa at 30 kN load) and did not reflect the surface-related stress expressions. Our results show that the use of wide, low pressure...

Measuring of vertical stroke Vub vertical stroke in the forthcoming decade

International Nuclear Information System (INIS)

Kim, C.S.

1997-01-01

I first introduce the importance of measuring V ub precisely. Then, from a theoretician's point of view, I review (a) past history, (b) present trials, and (c) possible future alternatives on measuring vertical stroke V ub vertical stroke and/or vertical stroke V ub /V cb vertical stroke. As of my main topic, I introduce a model-independent method, which predicts Γ(B→X u lν)/Γ(B→X c lν)≡(γ u /γ c ) x vertical stroke V ub /V cb vertical stroke 2 ≅(1.83±0.28) x vertical stroke V ub /V cb vertical stroke 2 and vertical stroke V ub /V cb vertical stroke ≡(γ c /γ u ) 1/2 x [B(B→X u lν)/B(B→ X c lν]) 1/2 ≅(0.74±0.06) x [B(B→X u lν/)B(B→X c lν)] 1/2 , based on the heavy quark effective theory I also explore the possible experimental options to separate B→X u lν from the dominant B→X c lν: the measurement of inclusive hadronic invariant mass distributions, and the 'D-π' (and 'K-π') separation conditions I also clarify the relevant experimental backgrounds. (orig.)

Attitudes toward opioid substitution therapy and pre-incarceration HIV transmission behaviors among HIV-infected prisoners in Malaysia: implications for secondary prevention.

Science.gov (United States)

Bachireddy, Chethan; Bazazi, Alexander R; Kavasery, Ravi; Govindasamy, Sumathi; Kamarulzaman, Adeeba; Altice, Frederick L

2011-07-01

Pre-incarceration HIV transmission behaviors and current attitudes toward opioid substitution therapy (OST) among HIV-infected male prisoners in Malaysia have important implications for secondary HIV prevention efforts. In June 2007, 102 HIV-infected male prisoners within 6 months of community-release were anonymously surveyed in Kota Bharu, Malaysia. Nearly all subjects (95%) met criteria for opioid dependence. Overall, 66% of participants reported sharing needles, and 37% reported unprotected sex in the 30 days prior to incarceration. During this period, 77% reported injection drug use, with 71% injecting daily and 65% injecting more than one substance. Injection of buprenorphine (28%), benzodiazepines (28%) and methamphetamines (49%) was reported. Nearly all (97%) of those reporting unprotected sex did so with someone not known to be HIV-infected. While 51% believed that opioid substitution therapy (OST) would be helpful, only 33% believed they needed it to prevent relapse after prison release. Most participants (70%) expressed interest in learning more about OST. Those reporting the highest injection risks were more likely to believe OST would be helpful (pMalaysia is crucial to reduce community HIV transmission after release. Effectively reducing HIV risk associated with opioid injection will require OST expansion, including social marketing to improve its acceptability and careful monitoring. Access to sterile injection equipment, particularly for non-opioid injectors, and behavioral interventions that reduce sexual risk will also be required. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Understanding HIV Transmission Risk Behavior Among HIV-Infected South Africans Receiving Antiretroviral Therapy: An Information—Motivation—Behavioral Skills Model Analysis

Science.gov (United States)

Kiene, Susan M.; Fisher, William A.; Shuper, Paul A.; Cornman, Deborah H.; Christie, Sarah; MacDonald, Susan; Pillay, Sandy; Mahlase, Gethwana; Fisher, Jeffrey D.

2014-01-01

The current study applied the Information—Motivation—Behavioral Skills (IMB) model (J. D. Fisher & Fisher, 1992; W. A. Fisher & Fisher, 1993) to identify factors associated with HIV transmission risk behavior among HIV-infected South Africans receiving antiretroviral therapy (ART), a population of considerable significance for curtailing, or maintaining, South Africa’s generalized HIV epidemic. HIV prevention information, HIV prevention motivation, HIV prevention behavioral skills, and HIV transmission risk behavior were assessed in a sample of 1,388 South Africans infected with HIV and receiving ART in 16 clinics in KwaZulu-Natal, South Africa. Results confirmed the assumptions of the IMB model and demonstrated that HIV prevention information and HIV prevention motivation work through HIV prevention behavioral skills to affect HIV transmission risk behavior in this population. Subanalyses confirmed these relationships for HIV transmission risk behavior overall and for HIV transmission risk behavior with partners perceived to be HIV-negative or HIV-status unknown. A consistent pattern of gender differences showed that for men, HIV prevention information and HIV prevention motivation may have direct links with HIV preventive behavior, while for women, the effects of HIV prevention information and HIV prevention motivation work through HIV prevention behavioral skills to affect HIV preventive behavior. These IMB model-based findings suggest directions for HIV prevention interventions with South African men and women living with HIV and on ART as an important component of overall strategies to contain South Africa’s generalized HIV epidemic. PMID:23477576

Human immunodeficiency virus type 1 mother-to-child transmission and prevention: successes and controversies.

Science.gov (United States)

Cavarelli, M; Scarlatti, G

2011-12-01

The World Health Organization (WHO) and United Nations Programme on HIV/AIDS (UNAIDS) estimated that an additional 370 000 new human immunodeficiency virus type 1 (HIV-1) infections occurred in children in 2009, mainly through mother-to-child transmission (MTCT). Intrapartum transmission contributes to approximately 20-25% of infections, in utero transmission to 5-10% and postnatal transmission to an additional 10-15% of cases. MTCT accounts for only a few hundred infected newborns in those countries in which services are established for voluntary counselling and testing of pregnant women, and a supply of antiretroviral drugs is available throughout pregnancy with recommendations for elective Caesarean section and avoidance of breastfeeding. The single-dose nevirapine regimen has provided the momentum to initiate MTCT programmes in many resource-limited countries; however, regimens using a combination of antiretroviral drugs are needed also to effectively reduce transmission via breastfeeding. 2011 The Association for the Publication of the Journal of Internal Medicine.

Quantifying vertical stress transmission and compaction-induced soil structure using sensor mat and X-ray computed tomography

DEFF Research Database (Denmark)

Naveed, Muhammad; Schjønning, Per; Keller, Thomas

2016-01-01

tillage. In this study, partially confined uniaxial compression tests were carried out on intact topsoil columns placed on subsoil columns. Two methods were employed for estimation of stress transmission in soil: (i) soil deformation patterns were quantified using X-ray CT and converted to stress......Accurate estimation of stress transmission in soil and quantification of compaction-induced soil pore structure is important for efficient soil use and management. Continuum mechanics have so far mostly been applied for agricultural soils, even if topsoil structure is aggregated due to regular...... distributions, and (ii) a tactile sensor mat was employed for measuring stresses at the interface of the topsoil and subsoil columns. The resulting soil pore structure under applied stresses was quantified using X-ray CT and by air-permeability measurements. In topsoil discrete stress transmission patterns were...

Understanding HIV transmission risk behavior among HIV-infected South Africans receiving antiretroviral therapy: an information--motivation--behavioral skills model analysis.

Science.gov (United States)

Kiene, Susan M; Fisher, William A; Shuper, Paul A; Cornman, Deborah H; Christie, Sarah; Macdonald, Susan; Pillay, Sandy; Mahlase, Gethwana; Fisher, Jeffrey D

2013-08-01

The current study applied the Information-Motivation-Behavioral Skills (IMB) model (Fisher & Fisher, 1992; Fisher & Fisher, 1993) to identify factors associated with human immunodeficiency virus (HIV) transmission risk behavior among HIV-infected South Africans receiving antiretroviral therapy (ART), a population of considerable significance for curtailing, or maintaining, South Africa's generalized HIV epidemic. HIV prevention information, HIV prevention motivation, HIV prevention behavioral skills, and HIV transmission risk behavior were assessed in a sample of 1,388 South Africans infected with HIV and receiving ART in 16 clinics in KwaZulu-Natal, South Africa. Findings confirmed the assumptions of the IMB model and demonstrated that HIV prevention information and HIV prevention motivation work through HIV prevention behavioral skills to affect HIV transmission risk behavior in this population. Subanalyses confirmed these relationships for HIV transmission risk behavior overall and for HIV transmission risk behavior with partners perceived to be HIV-negative or HIV-status unknown. A consistent pattern of gender differences showed that for men, HIV prevention information and HIV prevention motivation may have direct links with HIV preventive behavior, whereas for women, the effect of HIV prevention motivation works through HIV prevention behavioral skills to affect HIV preventive behavior. These IMB model-based findings suggest directions for HIV prevention interventions with South African men and women living with HIV and on ART as an important component of overall strategies to contain South Africa's generalized HIV epidemic. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Effectiveness of intermittent preventive treatment with sulfadoxine-pyrimethamine during pregnancy on placental malaria, maternal anaemia and birthweight in areas with high and low malaria transmission intensity in Tanzania.

Science.gov (United States)

Mosha, Dominic; Chilongola, Jaffu; Ndeserua, Rabi; Mwingira, Felista; Genton, Blaise

2014-09-01

To assess the effectiveness of IPTp in two areas with different malaria transmission intensities. Prospective observational study recruiting pregnant women in two health facilities in areas with high and low malaria transmission intensities. A structured questionnaire was used for interview. Maternal clinic cards and medical logs were assessed to determine drug intake. Placental parasitaemia was screened using both light microscopy and real-time quantitative PCR. Of 350 pregnant women were recruited and screened for placental parasitaemia, 175 from each area. Prevalence of placental parasitaemia was 16.6% (CI 11.4-22.9) in the high transmission area and 2.3% (CI 0.6-5.7) in the low transmission area. Being primigravida and residing in a high transmission area were significant risk factors for placental malaria (OR 2.4; CI 1.1-5.0; P = 0.025) and (OR 9.4; CI 3.2-27.7; P anaemia or low birthweight, regardless of transmission intensity. The number needed to treat (NNT) was four (CI 2-6) women in the high transmission area and 33 (20-50) in the low transmission area to prevent one case of placental malaria. IPTp may have an effect on lowering the risk of placental malaria in areas of high transmission, but this effect did not translate into a benefit on risks of maternal anaemia or low birthweight. The NNT needs to be considered, and weighted against that of other protective measures, eventually targeting areas which are above a certain threshold of malaria transmission to maximise the benefit. © 2014 John Wiley & Sons Ltd.

Lack of knowledge about mother-to-child HIV transmission prevention in pregnant women at Tijuana General Hospital, Baja California, Mexico.

Science.gov (United States)

Becka, Chandra M; Chacón-Cruz, Enrique; Araneta, Maria Rosario; Viani, Rolando M

2015-01-01

The objective of this study was to identify determinants of human immunodeficiency virus (HIV) knowledge regarding mother-to-child transmission (MTCT) among pregnant women at Tijuana General Hospital, Baja California, Mexico. Between March and November 2003, patients from the prenatal care (n = 1294) and labor and delivery (L&D) units (n = 495) participated in a cross-sectional study to measure HIV knowledge. Less than one-third (30%) knew that HIV could be transmitted to a child during delivery, and 36% knew that HIV could be transmitted by breast-feeding. Only 27% knew that an MTCT could be prevented. Prenatal patients were more likely to know that MTCT was preventable (prenatal: 31% versus L&D 25%; P = .02). Logistic regression indicated that prenatal patients (odds ratio = 1.49, confidence interval 1.07-2.07) were more likely to know that HIV could be transmitted through breast-feeding. Overall, both groups had poor knowledge regarding MTCT of HIV. © The Author(s) 2014.

Proactive infection control measures to prevent nosocomial transmission of vancomycin-resistant enterococci in Hong Kong.

Science.gov (United States)

Cheng, Vincent Chi-Chung; Tai, Josepha Wai-Ming; Chen, Jonathan Hon-Kwan; So, Simon Yung-Chun; Ng, Wing-Chun; Hung, Ivan Fan-Ngan; Leung, Sally Sau-Man; Wong, Sally Cheuk-Ying; Chan, Tuen-Ching; Chan, Felix Hon-Wai; Ho, Pak-Leung; Yuen, Kwok-Yung

2014-10-01

The study describes a proactive infection control approach to prevent nosocomial transmission of vancomycin-resistant enterococci (VRE) and tests if this approach is effective for controlling multiple-drug resistant organisms in a nonendemic setting. In response to the increasing prevalence of VRE in Hong Kong since 2011, we adopted a multifaceted assertive approach in our health care network. This included active surveillance culture, extensive contact tracing, directly observed hand hygiene in conscious patients before they received meals and medications, stringent hand hygiene and environmental cleanliness, and an immediate feedback antimicrobial stewardship program. We report the occurrence of VRE outbreaks in our hospital after institution of these measures and compared with the concurrent occurrence in other public hospitals in Hong Kong. Between July 1, 2011 and November 13, 2013, VRE was identified in 0.32% (50/15,851) of admission episodes by active surveillance culture. The risk of VRE carriage was three times higher in patients with a history of hospitalization outside our hospital networks in the past 3 months (0.56% vs. 0.17%; p = 0.001) compared with those who were not. Extensive contact tracing involving 3277 patient episodes was performed in the investigation for the 25 VRE index patients upon whom implementation of contact precautions was delayed (more than 48 hours of hospitalization). One episode of VRE outbreak was identified in our hospital network, compared with the 77 VRE outbreaks reported in the other hospital networks (controls) without these proactive infection control measures. Our multifaceted assertive proactive infection control approach can minimize the nosocomial transmission and outbreak of VRE in a nonendemic area. Copyright © 2014. Published by Elsevier B.V.

[Consensus statement on monitoring of HIV: pregnancy, birth, and prevention of mother-to-child transmission].

Science.gov (United States)

Polo Rodríguez, Rosa; Muñoz Galligo, Eloy; Iribarren, José Antonio; Domingo Pedrol, Pere; Leyes García, María; Maiques Montesinos, Vicente; Miralles Martín, Pilar; Noguera Julian, Antoni; Ocampo Hernández, Antonio; Péres Bares, María Lourdes; López Rojano, Marta; Suy Franch, Anna; Viñuela Beneitez, María Carmen; González Tomé, María Isabel

2014-05-01

The main objective in the management of HIV-infected pregnant women is prevention of mother-to-child transmission; therefore, it is essential to provide universal antiretroviral treatment, regardless of CD4 count. All pregnant women must receive adequate information and undergo HIV serology testing at the first visit. We assembled a panel of experts appointed by the Secretariat of the National AIDS Plan (SPNS) and the other participating Scientific Societies, which included internal medicine physicians with expertise in the field of HIV infection, gynecologists, pediatricians and psychologists. Four panel members acted as coordinators. Scientific information was reviewed in publications and conference reports up to November 2012. In keeping with the criteria of the Infectious Diseases Society of America, 2levels of evidence were applied to support the proposed recommendations: the strength of the recommendation according to expert opinion (A, B, C), and the level of empirical evidence (I, II, III). This approach has already been used in previous documents from SPNS. The aim of this paper was to review current scientific knowledge, and, accordingly, develop a set of recommendations regarding antiretroviral therapy (ART), regarding the health of the mother, and from the perspective of minimizing mother-to-child transmission (MTCT), also taking into account the rest of the health care of pregnant women with HIV infection. We also discuss and evaluate other strategies to reduce the MTCT (elective Cesarean, child's treatment…), and different aspects of the topic (ARV regimens, their toxicity, monitoring during pregnancy and postpartum, etc.). Copyright © 2013 Elsevier España, S.L. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

How Do People Become W.E.I.R.D.? Migration Reveals the Cultural Transmission Mechanisms Underlying Variation in Psychological Processes.

Directory of Open Access Journals (Sweden)

Alex Mesoudi

Full Text Available Cultural psychologists have shown that people from Western, Educated, Industrialised, Rich, Democratic (WEIRD countries often exhibit different psychological processing to people from less-WEIRD countries. The former exhibit more individualistic and less collectivistic social orientation, and more analytic and less holistic cognition, than non-Westerners. Yet the mechanisms responsible for maintaining this cultural variation are unclear. Immigration is an ideal 'natural experiment' for uncovering such mechanisms. We used a battery of psychological measures previously shown to vary cross-culturally to compare the social orientation and cognitive style of 286 residents of East London from three cultural backgrounds: (i 1st-generation British Bangladeshi immigrants; (ii 2nd-generation British Bangladeshis raised in the UK to Bangladeshi-raised parents; and (iii non-migrants whose parents were born and raised in the UK. Model comparison revealed that individualism and dispositional attribution, typical of Western societies, are driven primarily by horizontal cultural transmission (e.g. via mass media, with parents and other family members having little or no effect, while collectivism, social closeness and situational attribution were driven by a mix of vertical/oblique cultural transmission (e.g. via family contact and horizontal cultural transmission. These individual-level transmission dynamics can explain hitherto puzzling population-level phenomena, such as the partial acculturation of 2nd-generation immigrants on measures such as collectivism (due to the mix of vertical and horizontal cultural transmission, or the observation in several countries of increasing individualism (which is transmitted horizontally and therefore rapidly despite little corresponding change in collectivism (which is transmitted partly vertically and therefore more slowly. Further consideration of cultural transmission mechanisms, in conjunction with the study of

How Do People Become W.E.I.R.D.? Migration Reveals the Cultural Transmission Mechanisms Underlying Variation in Psychological Processes.

Science.gov (United States)

Mesoudi, Alex; Magid, Kesson; Hussain, Delwar

2016-01-01

Cultural psychologists have shown that people from Western, Educated, Industrialised, Rich, Democratic (WEIRD) countries often exhibit different psychological processing to people from less-WEIRD countries. The former exhibit more individualistic and less collectivistic social orientation, and more analytic and less holistic cognition, than non-Westerners. Yet the mechanisms responsible for maintaining this cultural variation are unclear. Immigration is an ideal 'natural experiment' for uncovering such mechanisms. We used a battery of psychological measures previously shown to vary cross-culturally to compare the social orientation and cognitive style of 286 residents of East London from three cultural backgrounds: (i) 1st-generation British Bangladeshi immigrants; (ii) 2nd-generation British Bangladeshis raised in the UK to Bangladeshi-raised parents; and (iii) non-migrants whose parents were born and raised in the UK. Model comparison revealed that individualism and dispositional attribution, typical of Western societies, are driven primarily by horizontal cultural transmission (e.g. via mass media), with parents and other family members having little or no effect, while collectivism, social closeness and situational attribution were driven by a mix of vertical/oblique cultural transmission (e.g. via family contact) and horizontal cultural transmission. These individual-level transmission dynamics can explain hitherto puzzling population-level phenomena, such as the partial acculturation of 2nd-generation immigrants on measures such as collectivism (due to the mix of vertical and horizontal cultural transmission), or the observation in several countries of increasing individualism (which is transmitted horizontally and therefore rapidly) despite little corresponding change in collectivism (which is transmitted partly vertically and therefore more slowly). Further consideration of cultural transmission mechanisms, in conjunction with the study of migrant

How Do People Become W.E.I.R.D.? Migration Reveals the Cultural Transmission Mechanisms Underlying Variation in Psychological Processes

Science.gov (United States)

Mesoudi, Alex; Magid, Kesson; Hussain, Delwar

2016-01-01

Cultural psychologists have shown that people from Western, Educated, Industrialised, Rich, Democratic (WEIRD) countries often exhibit different psychological processing to people from less-WEIRD countries. The former exhibit more individualistic and less collectivistic social orientation, and more analytic and less holistic cognition, than non-Westerners. Yet the mechanisms responsible for maintaining this cultural variation are unclear. Immigration is an ideal ‘natural experiment’ for uncovering such mechanisms. We used a battery of psychological measures previously shown to vary cross-culturally to compare the social orientation and cognitive style of 286 residents of East London from three cultural backgrounds: (i) 1st-generation British Bangladeshi immigrants; (ii) 2nd-generation British Bangladeshis raised in the UK to Bangladeshi-raised parents; and (iii) non-migrants whose parents were born and raised in the UK. Model comparison revealed that individualism and dispositional attribution, typical of Western societies, are driven primarily by horizontal cultural transmission (e.g. via mass media), with parents and other family members having little or no effect, while collectivism, social closeness and situational attribution were driven by a mix of vertical/oblique cultural transmission (e.g. via family contact) and horizontal cultural transmission. These individual-level transmission dynamics can explain hitherto puzzling population-level phenomena, such as the partial acculturation of 2nd-generation immigrants on measures such as collectivism (due to the mix of vertical and horizontal cultural transmission), or the observation in several countries of increasing individualism (which is transmitted horizontally and therefore rapidly) despite little corresponding change in collectivism (which is transmitted partly vertically and therefore more slowly). Further consideration of cultural transmission mechanisms, in conjunction with the study of migrant

Fault prevention by early stage symptoms detection for automatic vehicle transmission using pattern recognition and curve fitting

Science.gov (United States)

Balbin, Jessie R.; Cruz, Febus Reidj G.; Abu, Jon Ervin A.; Siño, Carlo G.; Ubaldo, Paolo E.; Zulueta, Christelle Jianne T.

2017-06-01

Automobiles have become essential parts of our everyday lives. It can correlate many factors that may affect a vehicle primarily those which may inconvenient or in some cases harm lives or properties. Thus, focusing on detecting an automatic transmission vehicle engine, body and other parts that cause vibration and sound may help prevent car problems using MATLAB. By using sound, vibration, and temperature sensors to detect the defects of the car and with the help of the transmitter and receiver to gather data wirelessly, it is easy to install on to the vehicle. A technique utilized from Toyota Balintawak Philippines that every car is treated as panels(a, b, c, d, and e) 'a' being from the hood until the front wheel of the car and 'e' the rear shield to the back of the car, this was applied on how to properly place the sensors so that precise data could be gathered. Data gathered would be compared to the normal graph taken from the normal status or performance of a vehicle, data that would surpass 50% of the normal graph would be considered that a problem has occurred. The system is designed to prevent car accidents by determining the current status or performance of the vehicle, also keeping people away from harm.

Reasoning About Cultural and Genetic Transmission: Developmental and Cross-Cultural Evidence From Peru, Fiji, and the United States on How People Make Inferences About Trait Transmission.

Science.gov (United States)

Moya, Cristina; Boyd, Robert; Henrich, Joseph

2015-10-01

Using samples from three diverse populations, we test evolutionary hypotheses regarding how people reason about the inheritance of various traits. First, we provide a framework for differentiat-ing the outputs of mechanisms that evolved for reasoning about variation within and between (a) biological taxa and (b) culturally evolved ethnic categories from (c) a broader set of beliefs and categories that are the outputs of structured learning mechanisms. Second, we describe the results of a modified "switched-at-birth" vignette study that we administered among children and adults in Puno (Peru), Yasawa (Fiji), and adults in the United States. This protocol permits us to study perceptions of prenatal and social transmission pathways for various traits and to differentiate the latter into vertical (i.e., parental) versus horizontal (i.e., peer) cultural influence. These lines of evidence suggest that people use all three mechanisms to reason about the distribution of traits in the population. Participants at all three sites develop expectations that morphological traits are under prenatal influence, and that belief traits are more culturally influenced. On the other hand, each population holds culturally specific beliefs about the degree of social influence on non-morphological traits and about the degree of vertical transmission-with only participants in the United States expecting parents to have much social influence over their children. We reinterpret people's differentiation of trait transmission pathways in light of humans' evolutionary history as a cultural species. Copyright © 2015 Cognitive Science Society, Inc.

Effective seat-to-head transmissibility in whole-body vibration: Effects of posture and arm position

Science.gov (United States)

Rahmatalla, Salam; DeShaw, Jonathan

2011-12-01

Seat-to-head transmissibility is a biomechanical measure that has been widely used for many decades to evaluate seat dynamics and human response to vibration. Traditionally, transmissibility has been used to correlate single-input or multiple-input with single-output motion; it has not been effectively used for multiple-input and multiple-output scenarios due to the complexity of dealing with the coupled motions caused by the cross-axis effect. This work presents a novel approach to use transmissibility effectively for single- and multiple-input and multiple-output whole-body vibrations. In this regard, the full transmissibility matrix is transformed into a single graph, such as those for single-input and single-output motions. Singular value decomposition and maximum distortion energy theory were used to achieve the latter goal. Seat-to-head transmissibility matrices for single-input/multiple-output in the fore-aft direction, single-input/multiple-output in the vertical direction, and multiple-input/multiple-output directions are investigated in this work. A total of ten subjects participated in this study. Discrete frequencies of 0.5-16 Hz were used for the fore-aft direction using supported and unsupported back postures. Random ride files from a dozer machine were used for the vertical and multiple-axis scenarios considering two arm postures: using the armrests or grasping the steering wheel. For single-input/multiple-output, the results showed that the proposed method was very effective in showing the frequencies where the transmissibility is mostly sensitive for the two sitting postures and two arm positions. For multiple-input/multiple-output, the results showed that the proposed effective transmissibility indicated higher values for the armrest-supported posture than for the steering-wheel-supported posture.

Lossy transmission line model of hydrofractured well dynamics

Energy Technology Data Exchange (ETDEWEB)

Patzek, T.W. [Department of Materials Science and Mineral Engineering, University of California at Berkeley, Berkeley, CA (United States); De, A. [Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

2000-01-01

The real-time detection of hydrofracture growth is crucial to the successful operation of water, CO{sub 2} or steam injection wells in low-permeability reservoirs and to the prevention of subsidence and well failure. In this paper, we describe propagation of very low frequency (1-10 to 100 Hz) Stoneley waves in a fluid-filled wellbore and their interactions with the fundamental wave mode in a vertical hydrofracture. We demonstrate that Stoneley-wave loses energy to the fracture and the energy transfer from the wellbore to the fracture opening is most efficient in soft rocks. We conclude that placing the wave source and receivers beneath the injection packer provides the most efficient means of hydrofracture monitoring. We then present the lossy transmission line model of wellbore and fracture for the detection and characterization of fracture state and volume. We show that this model captures the wellbore and fracture geometry, the physical properties of injected fluid and the wellbore-fracture system dynamics. The model is then compared with experimentally measured well responses. The simulated responses are in good agreement with published experimental data from several water injection wells with depths ranging from 1000 ft to 9000 ft. Hence, we conclude that the transmission line model of water injectors adequately captures wellbore and fracture dynamics. Using an extensive data set for the South Belridge Diatomite waterfloods, we demonstrate that even for very shallow wells the fracture size and state can be adequately recognized at wellhead. Finally, we simulate the effects of hydrofracture extension on the transient response to a pulse signal generated at wellhead. We show that hydrofracture extensions can indeed be detected by monitoring the wellhead pressure at sufficiently low frequencies.

Synthesis of subnanometer-diameter vertically aligned single-walled carbon nanotubes with copper-anchored cobalt catalysts

Science.gov (United States)

Cui, Kehang; Kumamoto, Akihito; Xiang, Rong; An, Hua; Wang, Benjamin; Inoue, Taiki; Chiashi, Shohei; Ikuhara, Yuichi; Maruyama, Shigeo

2016-01-01

We synthesize vertically aligned single-walled carbon nanotubes (VA-SWNTs) with subnanometer diameters on quartz (and SiO2/Si) substrates by alcohol CVD using Cu-anchored Co catalysts. The uniform VA-SWNTs with a nanotube diameter of 1 nm are synthesized at a CVD temperature of 800 °C and have a thickness of several tens of μm. The diameter of SWNTs was reduced to 0.75 nm at 650 °C with the G/D ratio maintained above 24. Scanning transmission electron microscopy energy-dispersive X-ray spectroscopy (EDS-STEM) and high angle annular dark field (HAADF-STEM) imaging of the Co/Cu bimetallic catalyst system showed that Co catalysts were captured and anchored by adjacent Cu nanoparticles, and thus were prevented from coalescing into a larger size, which contributed to the small diameter of SWNTs. The correlation between the catalyst size and the SWNT diameter was experimentally clarified. The subnanometer-diameter and high-quality SWNTs are expected to pave the way to replace silicon for next-generation optoelectronic and photovoltaic devices.We synthesize vertically aligned single-walled carbon nanotubes (VA-SWNTs) with subnanometer diameters on quartz (and SiO2/Si) substrates by alcohol CVD using Cu-anchored Co catalysts. The uniform VA-SWNTs with a nanotube diameter of 1 nm are synthesized at a CVD temperature of 800 °C and have a thickness of several tens of μm. The diameter of SWNTs was reduced to 0.75 nm at 650 °C with the G/D ratio maintained above 24. Scanning transmission electron microscopy energy-dispersive X-ray spectroscopy (EDS-STEM) and high angle annular dark field (HAADF-STEM) imaging of the Co/Cu bimetallic catalyst system showed that Co catalysts were captured and anchored by adjacent Cu nanoparticles, and thus were prevented from coalescing into a larger size, which contributed to the small diameter of SWNTs. The correlation between the catalyst size and the SWNT diameter was experimentally clarified. The subnanometer-diameter and high

Elastic full-waveform inversion of transmission data in 2D VTI media

KAUST Repository

Kamath, Nishant; Tsvankin, Ilya

2014-01-01

Full-waveform inversion (FWI) has been implemented mostly for isotropic media, with extensions to anisotropic models typically limited to acoustic approximations. Here, we develop elastic FWI for transmitted waves in 2D heterogeneous VTI (transversely isotropic with a vertical symmetry axis) media. The model is parameterized in terms of the P- and S-wave vertical velocities and the P-wave normal-moveout and horizontal velocities. To test the FWI algorithm, we introduce Gaussian anomalies in the Thomsen parameters of a homogeneous VTI medium and perform FWI of transmission data for different configurations of the source and receiver arrays. The inversion results strongly depend on the acquisition geometry and the aperture because of the parameter trade-offs. In contrast to acoustic FWI, the elastic inversion helps constrain the S-wave vertical velocity, which for our model is decoupled from the other parameters.

Elastic full-waveform inversion of transmission data in 2D VTI media

KAUST Repository

Kamath, Nishant

2014-08-05

Full-waveform inversion (FWI) has been implemented mostly for isotropic media, with extensions to anisotropic models typically limited to acoustic approximations. Here, we develop elastic FWI for transmitted waves in 2D heterogeneous VTI (transversely isotropic with a vertical symmetry axis) media. The model is parameterized in terms of the P- and S-wave vertical velocities and the P-wave normal-moveout and horizontal velocities. To test the FWI algorithm, we introduce Gaussian anomalies in the Thomsen parameters of a homogeneous VTI medium and perform FWI of transmission data for different configurations of the source and receiver arrays. The inversion results strongly depend on the acquisition geometry and the aperture because of the parameter trade-offs. In contrast to acoustic FWI, the elastic inversion helps constrain the S-wave vertical velocity, which for our model is decoupled from the other parameters.

A cooperative game theory approach to transmission planning in power systems

Science.gov (United States)

Contreras, Javier

The rapid restructuring of the electric power industry from a vertically integrated entity into a decentralized industry has given rise to complex problems. In particular, the transmission component of the electric power system requires new methodologies to fully capture this emerging competitive industry. Game theory models are used to model strategic interactions in a competitive environment. This thesis presents a new decentralized framework to study the transmission network expansion problem using cooperative game theory. First, the players and the rules of the game are defined. Second, a coalition formation scheme is developed. Finally, the optimized cost of expansion is allocated based on the history of the coalition formation.

Leukodepletion Filters for Prevention of Transfusion Transmission Of Leishmania

Science.gov (United States)

2006-11-01

living in an area of endemicity in southern France. J Clin Microbiol 1999; 37(6):1953-1957 18 Hillyer CD, Emmens RK, Zago -Novaretti M , Berkman EM...Kostmann R, Barr M , Bengtsson E, Garnham PCC, Hult G: Kala-azar transferred by exchange blood transfusions in two Swedish infants. Proceedings of the...Dabadie A, Guiguen C, Roussey M : Visceral leishmaniasis in an infant in Brittany: Discussion on the modes of transmission outside of the endemic

how acceptable are the prevention of mother to child transmission

African Journals Online (AJOL)

TRANSMISSION (PMTCT) OF HIV SERVICES AMONG PREGNANT WOMEN IN A. SECONDARY HEALTH FACILITY IN ... of HIV were during pregnancy (86.0%) and from breastfeeding (86.0%). More than 80% knew that having good ..... The Role of HIV related stigma in utilisation of skilled childbirth services in rural ...

Transfusion transmissible viral infections among potential blood ...

African Journals Online (AJOL)

effective approach for prevention and control of transfusion-transmissible infections (TTIs). Also, it has been documented that sub-standard test kits are mostly used in resource limited settings for transfusion related diagnosis. However, the role of ...

Community perceptions on outdoor malaria transmission in Kilombero Valley, Southern Tanzania.

Science.gov (United States)

Moshi, Irene R; Ngowo, Halfan; Dillip, Angel; Msellemu, Daniel; Madumla, Edith P; Okumu, Fredros O; Coetzee, Maureen; Mnyone, Ladslaus L; Manderson, Lenore

2017-07-04

The extensive use of indoor residual spraying (IRS) and insecticide-treated nets (ITNs) in Africa has contributed to a significant reduction in malaria transmission. Even so, residual malaria transmission persists in many regions, partly driven by mosquitoes that bite people outdoors. In areas where Anopheles gambiae s.s. is a dominant vector, most interventions target the reduction of indoor transmission. The increased use of ITNs/LLINs and IRS has led to the decline of this species. As a result, less dominant vectors such as Anopheles funestus and Anopheles arabiensis, both also originally indoor vectors but are increasingly biting outdoors, contribute more to residual malaria transmission. The study reports the investigated community perceptions on malaria and their implications of this for ongoing outdoor malaria transmission and malaria control efforts. This was a qualitative study conducted in two rural villages and two peri-urban areas located in Kilombero Valley in south-eastern Tanzania. 40 semi-structured in-depth interviews and 8 focus group discussions were conducted with men and women who had children under the age of five. The Interviews and discussions focused on (1) community knowledge of malaria transmission, and (2) the role of such knowledge on outdoor malaria transmission as a contributing factor to residual malaria transmission. The use of bed nets for malaria prevention has been stressed in a number of campaigns and malaria prevention programmes. Most people interviewed believe that there is outdoor malaria transmission since they use interventions while indoors, but they are unaware of changing mosquito host-seeking behaviour. Participants pointed out that they were frequently bitten by mosquitoes during the evening when outdoors, compared to when they were indoors. Most participants stay outdoors in the early evening to undertake domestic tasks that cannot be conducted indoors. House structure, poor ventilation and warm weather conditions

Knowledge and attitudes about HIV infection and prevention of mother to child transmission of HIV in an urban, low income community in Durban, South Africa: Perspectives of residents and health care volunteers

Directory of Open Access Journals (Sweden)

Firoza Haffejee

2016-12-01

Conclusion: Innovative ways to impart knowledge particularly of PMTCT and updated standards of practice are essential. It is important that the community understands how transmission occurs so that prevention can follow.

Dynamic Analysis of a Floating Vertical Axis Wind Turbine Under Emergency Shutdown Using Hydrodynamic Brake

DEFF Research Database (Denmark)

Wang, K.; Hansen, Martin Otto Laver; Moan, T.

2014-01-01

Emergency shutdown is always a challenge for an operating vertical axis wind turbine. A 5-MW vertical axis wind turbine with a Darrieus rotor mounted on a semi-submersible support structure was examined in this study. Coupled non-linear aero-hydro-servo-elastic simulations of the floating vertical...... axis wind turbine were carried out for emergency shutdown cases over a range of environmental conditions based on correlated wind and wave data. When generator failure happens, a brake should be applied to stop the acceleration of the rotor to prevent the rotor from overspeeding and subsequent disaster...

Factors influencing the utilisation of prevention of mother-to-child transmission (PMTCT services by pregnant women in the Eastern Cape, South Africa

Directory of Open Access Journals (Sweden)

Karl Peltzer

2005-11-01

Full Text Available The aim of the study was to identify factors influencing the utilisation of Prevention of Mother-to-Child Transmission (PMTCT in a resource poor setting in South Africa. Opsomming Die doel van die studie was om faktore te identifiseer wat die benutting van die Voorkoming van Moeder-tot-Kind Oordrag (VMTKO beïnvloed in ‘n omgewing in Suid-Afrika wat arm is aan hulpbronne. *Please note: This is a reduced version of the abstract. Please refer to PDF for full text.

Horizontal transmission of group B streptococcus in a neonatal intensive care unit.

Science.gov (United States)

Morinis, Julia; Shah, Jay; Murthy, Prashanth; Fulford, Martha

2011-06-01

The incidence of early-onset group B streptococcal (GBS) sepsis in the neonatal population has decreased substantially since the introduction of maternal intrapartum antibiotic prophylaxis and routine prenatal screening. However, these strategies have not reduced the incidence of late-onset GBS infections. Additional research pertaining to the transmission of late-onset GBS infections is required to develop effective preventive methods. The present report describes probable horizontal transmission of late-onset GBS infection among three infants in a neonatal intensive care unit. GBS strain confirmation was based on the microbiological picture, antibiogram and pulsed-field gel electrophoresis. These cases highlight the morbidity associated with late-onset GBS disease and the importance of considering horizontal transmission as an etiological factor in GBS infection in the newborn period. Further studies assessing horizontal transmission in late-onset GBS disease may improve prevention and early intervention.

Risk analysis and assessment of vertical and incline small winder systems and peripheral activities.

CSIR Research Space (South Africa)

Moss, PS

2000-01-01

Full Text Available access .......................................................48 3.6.3 "ramped" design of station access ..................................................................49 3.6.4 Handling of material cars... vertical plane using a rope and counterweight mechanism, to allow the passage of cars when required. It is extensively used to prevent the inadvertent entry of material cars from stations into incline shafts, and to derail a runaway car so preventing...

Systematic review on tuberculosis transmission on aircraft and update of the European Centre for Disease Prevention and Control risk assessment guidelines for tuberculosis transmitted on aircraft (RAGIDA-TB).

Science.gov (United States)

Kotila, Saara M; Payne Hallström, Lara; Jansen, Niesje; Helbling, Peter; Abubakar, Ibrahim

2016-01-01

As a setting for potential tuberculosis (TB) transmission and contact tracing, aircraft pose specific challenges. Evidence-based guidelines are needed to support the related-risk assessment and contact-tracing efforts. In this study evidence of TB transmission on aircraft was identified to update the Risk Assessment Guidelines for TB Transmitted on Aircraft (RAGIDA-TB) of the European Centre for Disease Prevention and Control (ECDC). Electronic searches were undertaken from Medline (Pubmed), Embase and Cochrane Library until 19 July 2013. Eligible records were identified by a two-stage screening process and data on flight and index case characteristics as well as contact tracing strategies extracted. The systematic literature review retrieved 21 records. Ten of these records were available only after the previous version of the RAGIDA guidelines (2009) and World Health Organization guidelines on TB and air travel (2008) were published. Seven of the 21 records presented some evidence of possible in-flight transmission, but only one record provided substantial evidence of TB transmission on an aircraft. The data indicate that overall risk of TB transmission on aircraft is very low. The updated ECDC guidelines for TB transmission on aircraft have global implications due to inevitable need for international collaboration in contract tracing and risk assessment.

Optoelectronic integrated circuits utilising vertical-cavity surface-emitting semiconductor lasers

International Nuclear Information System (INIS)

Zakharov, S D; Fyodorov, V B; Tsvetkov, V V

1999-01-01

Optoelectronic integrated circuits with additional optical inputs/outputs, in which vertical-cavity surface-emitting (VCSE) lasers perform the data transfer functions, are considered. The mutual relationship and the 'affinity' between optical means for data transfer and processing, on the one hand, and the traditional electronic component base, on the other, are demonstrated in the case of implementation of three-dimensional interconnects with a high transmission capacity. Attention is drawn to the problems encountered when semiconductor injection lasers are used in communication lines. It is shown what role can be played by VCSE lasers in solving these problems. A detailed analysis is made of the topics relating to possible structural and technological solutions in the fabrication of single lasers and of their arrays, and also of the problems hindering integrating of lasers into emitter arrays. Considerable attention is given to integrated circuits with optoelectronic smart pixels. Various technological methods for vertical integration of GaAs VCSE lasers with the silicon substrate of a microcircuit (chip) are discussed. (review)

Role of trade-off between sexual and vertical routes for evolution of pathogen transmission

Czech Academy of Sciences Publication Activity Database

Bernhauerová, V.; Berec, Luděk

2015-01-01

Roč. 8, č. 1 (2015), s. 23-36 ISSN 1874-1738 Grant - others:Masaryk University(CZ) MUNI/A/0849/2012 Institutional support: RVO:60077344 Keywords : adaptive dynamics * frequency-dependent transmission * infectious disease Subject RIV: EH - Ecology, Behaviour Impact factor: 2.085, year: 2015 http://link.springer.com/article/10.1007%2Fs12080-014-0234-8

Vertical transmission of feather lice between adult blackbirds Turdus merula and their nestlings: a lousy perspective.

Science.gov (United States)

Brooke, M de L

2010-12-01

There is limited information about the natural history of the transmission of feather lice (Phthiraptera) from parent birds to their young. This article therefore examines the transmission of 4 species of feather lice from parent blackbirds to their nestlings in an English population, and addresses questions formulated from the perspective of the lice. The lice that disperse onto the several young in the nest were mostly found on the larger chicks, those with higher survival prospects. The lice dispersing to chicks were overwhelmingly nymphs, which cannot be sexed morphologically, and so the prediction that the adult lice dispersing would be disproportionately female, potential founders of a new population, was only supported for the most numerous species, Brueelia merulensis. There was no evidence that louse dispersal to chicks was density dependent and more likely when the parents were more heavily infested. Finally, I predicted that lice might aggregate on female blackbirds, which undertake more brooding, to increase their chance of transmission to nestlings. For 1 louse species, B. merulensis, prevalence, but not louse intensity, was higher on female than male blackbirds. For 2 other louse species, Philopterus turdi and Menacanthus eurysternus, no differences between male and female blackbirds were detected.

Sex, condoms, gender roles, and HIV transmission knowledge among adolescents in León, Nicaragua: implications for HIV prevention.

Science.gov (United States)

Manji, A; Peña, R; Dubrow, R

2007-09-01

There are few peer-reviewed studies of HIV/AIDS-related knowledge, attitudes, beliefs and practices among adolescents in Central America. A population-based cross-sectional survey was conducted among 246 adolescents in León, Nicaragua, where there is reason for concern about a rise in HIV infections. In many respects, León adolescents were typical of those in other Latin American countries, with a mixture of correct and incorrect knowledge about transmission of HIV and sexually transmitted infections, a higher proportion of males than females reporting having had sex or using condoms, and inconsistent condom use. While some sexual attitudes conformed to the ideology of machismo, others did not, providing an opening for prevention interventions. Some dimensions of HIV/AIDS stigma were high, and most adolescents disapproved of same-sex sexual behaviour. Intervention against homosexuality-related stigma is particularly urgent because a concentrated HIV epidemic may be emerging in Nicaragua among men who have sex with men. Personal religious beliefs did not appear to pose a barrier to condom use. In a multivariate model, being out of school was a significant correlate of having had sex and of insufficient HIV/AIDS-related knowledge. Accordingly, HIV prevention interventions must reach adolescents both in and out of school. A multi-component approach to prevention is needed, including programmes based in schools, communities, the mass media and health facilities.

Continuous Growth of Vertically Aligned Carbon Nanotubes Forests

OpenAIRE

Guzman de Villoria, Roberto; Wardle, Brian L.

2011-01-01

Vertically aligned carbon nanotubes are one of the most promising materials due their numerous applications in flexible electronic devices, biosensors and multifunctional aircraft materials, among others. However, the costly production of aligned carbon nanotubes, generally in a batch process, prevents their commercial use. For the first time, a controlled process to grow aligned carbon nanotubes in a continuous manner is presented. Uniform growth is achieved using 2D and 3D substrates. A sig...

Hepatitis C hos børn

DEFF Research Database (Denmark)

Christensen, Vibeke Brix; Nordly, Sannie Brit; Fischler, Bjørn

2014-01-01

Chronic hepatitis C (HCV) infection has a prevalence of 2-3% worldwide. The vertical transmission rate is approximately 5%. There is no evidence to recommend abstinence from breastfeeding or elective C-section to prevent transmission. In children, the natural history of HCV infection is typically...

Antiretroviral treatment response of HIV-infected children after prevention of mother-to-child transmission in West Africa

DEFF Research Database (Denmark)

Ndondoki, Camille; Dicko, Fatoumata; Ahuatchi Coffie, Patrick

2014-01-01

INTRODUCTION: We assessed the rate of treatment failure of HIV-infected children after 12 months on antiretroviral treatment (ART) in the Paediatric IeDEA West African Collaboration according to their perinatal exposure to antiretroviral drugs for preventing mother-to-child transmission (PMTCT......). METHODS: A retrospective cohort study in children younger than five years at ART initiation between 2004 and 2009 was nested within the pWADA cohort, in Bamako-Mali and Abidjan-Côte d'Ivoire. Data on PMTCT exposure were collected through a direct review of children's medical records. The 12-month Kaplan....... Immunological failure was defined according to the 2006 World Health Organization age-related immunological thresholds for severe immunodeficiency. RESULTS: Among the 1035 eligible children, PMTCT exposure was only documented for 353 children (34.1%) and remained unknown for 682 (65.9%). Among children...

Human prion diseases: surgical lessons learned from iatrogenic prion transmission.

Science.gov (United States)

Bonda, David J; Manjila, Sunil; Mehndiratta, Prachi; Khan, Fahd; Miller, Benjamin R; Onwuzulike, Kaine; Puoti, Gianfranco; Cohen, Mark L; Schonberger, Lawrence B; Cali, Ignazio

2016-07-01

The human prion diseases, or transmissible spongiform encephalopathies, have captivated our imaginations since their discovery in the Fore linguistic group in Papua New Guinea in the 1950s. The mysterious and poorly understood "infectious protein" has become somewhat of a household name in many regions across the globe. From bovine spongiform encephalopathy (BSE), commonly identified as mad cow disease, to endocannibalism, media outlets have capitalized on these devastatingly fatal neurological conditions. Interestingly, since their discovery, there have been more than 492 incidents of iatrogenic transmission of prion diseases, largely resulting from prion-contaminated growth hormone and dura mater grafts. Although fewer than 9 cases of probable iatrogenic neurosurgical cases of Creutzfeldt-Jakob disease (CJD) have been reported worldwide, the likelihood of some missed cases and the potential for prion transmission by neurosurgery create considerable concern. Laboratory studies indicate that standard decontamination and sterilization procedures may be insufficient to completely remove infectivity from prion-contaminated instruments. In this unfortunate event, the instruments may transmit the prion disease to others. Much caution therefore should be taken in the absence of strong evidence against the presence of a prion disease in a neurosurgical patient. While the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) have devised risk assessment and decontamination protocols for the prevention of iatrogenic transmission of the prion diseases, incidents of possible exposure to prions have unfortunately occurred in the United States. In this article, the authors outline the historical discoveries that led from kuru to the identification and isolation of the pathological prion proteins in addition to providing a brief description of human prion diseases and iatrogenic forms of CJD, a brief history of prion disease nosocomial transmission

Review of transmission routes of 24 infectious diseases preventable by biosecurity measures and comparison of the implementation of these measures in pig herds in six European countries.

Science.gov (United States)

Filippitzi, M E; Brinch Kruse, A; Postma, M; Sarrazin, S; Maes, D; Alban, L; Nielsen, L R; Dewulf, J

2018-04-01

This study aimed to review the transmission routes of important infectious pig diseases and to translate these into biosecurity measures preventing or reducing the transmission between and within pig herds. Furthermore, it aimed to identify the level of implementation of these measures in different European countries and discuss the observed variations to identify potentials for improvement. First, a literature review was performed to show which direct and indirect transmission routes of 24 infectious pig diseases can be prevented through different biosecurity measures. Second, a quantitative analysis was performed using the Biocheck.UGent™, a risk-based scoring system to evaluate biosecurity in pig herds, to obtain an insight into the implementation of these biosecurity measures. The database contained farm-specific biosecurity data from 574 pig farms in Belgium, Denmark, France, Germany, the Netherlands and Sweden, entered between January 2014 and January 2016. Third, a qualitative analysis based on a review of literature and other relevant information resources was performed for every subcategory of internal and external biosecurity in the Biocheck.UGent™ questionnaire. The quantitative analysis indicated that at the level of internal, external and overall biosecurity, Denmark had a significantly distinct profile with higher external biosecurity scores and less variation than the rest of the countries. This is likely due to a widely used specific pathogen-free (SPF) system with extensive focus on biosecurity since 1971 in Denmark. However, the observed pattern may also be attributed to differences in data collection methods. The qualitative analysis identified differences in applied policies, legislation, disease status, pig farm density, farming culture and habits between countries that can be used for shaping country-specific biosecurity advice to attain improved prevention and control of important pig diseases in European pig farms. © 2017 Blackwell

Measurement of vertical stroke Vub vertical stroke using b hadron semileptonic decay

International Nuclear Information System (INIS)

Abbiendi, G.; Aakesson, P.F.

2001-01-01

The magnitude of the CKM matrix element vertical stroke V ub vertical stroke is determined by measuring the inclusive charmless semileptonic branching fraction of beauty hadrons at OPAL based on b → X u lν event topology and kinematics. This analysis uses OPAL data collected between 1991 and 1995, which correspond to about four million hadronic Z decays. We measure Br(b → X u lν) to be (1.63 ±0.53 +0.55 -0.62 ) x 10 -3 . The first uncertainty is the statistical error and the second is the systematic error. From this analysis, vertical stroke V ub vertical stroke is determined to be: vertical stroke V ub vertical stroke =(4.00±0.65(stat) +0.67 -0.76 (sys)±0.19(HQE)) x 10 -3 . The last error represents the theoretical uncertainties related to the extraction of vertical stroke V ub vertical stroke from Br(b→X u l ν) using the Heavy Quark Expansion. (orig.)

Optimization of tenofovir release from mucoadhesive vaginal tablets by polymer combination to prevent sexual transmission of HIV.

Science.gov (United States)

Notario-Pérez, Fernando; Cazorla-Luna, Raúl; Martín-Illana, Araceli; Ruiz-Caro, Roberto; Tamayo, Aitana; Rubio, Juan; Veiga, María-Dolores

2018-01-01

The use of sustained-release mucoadhesive vaginal tablets of antiretroviral drugs as microbicidal formulations can be an effective strategy for reducing the sexual transmission of HIV from men to women, which is a main problem particularly in low- and middle-income countries. Different polymers (hydroxypropylmethyl cellulose (HPMC), chitosan, guar gum and Eudragit ® RS) have proven some good features for this purpose. At this work, these polymers have been combined in pairs in different proportions to enhance the advantages offered by each one individually. The in vitro release of tenofovir from the matrices, ex vivo mucoadhesive capacity (evaluated on vaginal mucosa) and the degree of swelling in simulated vaginal fluid have been assessed. A multimodal pore size distribution is observed in porosimetry studies -carried out with swelling witnesses-, due to the contribution of polymers with different swelling behaviour to the pore formation, and it is corroborated by scanning electron microscopy. X-ray diffraction technique confirms the changes in crystallinity of the formulation after swelling. We can report that the combination of HPMC and chitosan in the same formulation may be useful for the prevention of sexual transmission of HIV, since tablets can be obtained that remain adhered to the vaginal mucosa for 96h, so the drug is released in a sustained manner for 72h. When the formulation contains more chitosan than HPMC the swelling is moderate, making it more comfortable for women to apply. Copyright © 2017. Published by Elsevier Ltd.