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31.
In mouse cells transformed by a temperature-sensitive polyoma virus (Py) genome, the integrated viral genome recombines with adjacent chromosomal DNA to yield a small cyclic molecule (RmI) with defined viral and cellular components. We have cloned the cellular component (Ins), determined its sequence, and examined its distribution in normal mouse DNA. The sequence of Ins displays several homologies with that surrounding the replication origin (ori) of Py or SV40 DNA. 相似文献
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Epidemiology of mixed Schistosoma mansoni and Schistosoma haematobium infections in northern Senegal
Meurs L Mbow M Vereecken K Menten J Mboup S Polman K 《International journal for parasitology》2012,42(3):305-311
Due to the large overlap of Schistosoma mansoni- and Schistosoma haematobium-endemic regions in Africa, many people are at risk of co-infection, with potential adverse effects on schistosomiasis morbidity and control. Nonetheless, studies on the distribution and determinants of mixed Schistosoma infections have to date been rare. We conducted a cross-sectional survey in two communities in northern Senegal (n=857) to obtain further insight into the epidemiology of mixed infections and ectopic egg elimination. Overall prevalences of S. mansoni and S. haematobium infection were 61% and 50%, respectively, in these communities. Among infected subjects, 53% had mixed infections and 8% demonstrated ectopic egg elimination. Risk factors for mixed infection - i.e. gender, community of residence and age - were not different from what is generally seen in Schistosoma-endemic areas. Similar to overall S. mansoni and S. haematobium infections, age-related patterns of mixed infections showed the characteristic convex-shaped curve for schistosomiasis, with a rapid increase in children, a peak in adolescents and a decline in adults. Looking at the data in more detail however, the decline in overall S. haematobium infection prevalences and intensities appeared to be steeper than for S. mansoni, resulting in a decrease in mixed infections and a relative increase in single S. mansoni infections with age. Moreover, individuals with mixed infections had higher infection intensities of both S. mansoni and S. haematobium than those with single infections, especially those with ectopic egg elimination (P<0.05). High infection intensities in mixed infections, as well as age-related differences in infection patterns between S. mansoni and S. haematobium, may influence disease epidemiology and control considerably, and merit further studies into the underlying mechanisms of Schistosoma infections in co-endemic areas. 相似文献
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Ravi Kavasery Duncan Smith-Rohrberg Maru Joshua Cornman-Homonoff Laurie N. Sylla David Smith Frederick L. Altice 《PloS one》2009,4(11)
Background
Ten million Americans enter jails annually. The objective was to evaluate new CDC guidelines for routine opt-out HIV testing and examine the optimal time to implement routine opt-out HIV testing among newly incarcerated jail detainees.Methods
This prospective, controlled trial of routine opt-out HIV testing was conducted among 323 newly incarcerated female inmates in Connecticut''s only women''s jail. 323 sequential entrants to the women''s jail over a five week period in August and September 2007 were assigned to be offered routine opt-out HIV testing at one of three points after incarceration: immediate (same day, n = 108), early (next day, n = 108), or delayed (7 days, n = 107). The primary outcome was the proportion of women in each group consenting to testing.Results
Routine opt-out HIV testing was significantly highest (73%) among the early testing group compared to 55% for immediate and 50% for 7 days post-entry groups. Other factors significantly (p = 0.01) associated with being HIV tested were younger age and low likelihood of early release from jail based on bond value or type of charge for which women were arrested.Conclusions
In this correctional facility, routine opt-out HIV testing in a jail setting was feasible, with highest rates of testing if performed the day after incarceration. Lower testing rates were seen with immediate testing, where there is a high prevalence of inability or unwillingness to test, and with delayed testing, where attrition from jail increases with each passing day.Trial Registration
ClinicalTrials.gov NCT00624247相似文献35.
Fabiano Oliveira Seydou Doumbia Jennifer M. Anderson Ousmane Faye Souleymane S. Diarra Pierre Traoré Moumine Cisse Guimba Camara Koureissi Tall Cheick A. Coulibaly Sibiry Samake Ibrahim Sissoko Bourama Traoré Daouda Diallo Somita Keita Rick M. Fairhurst Jesus G. Valenzuela Shaden Kamhawi 《PLoS neglected tropical diseases》2009,3(12)
Apart from a single report, the last publication of cutaneous leishmaniasis (CL) in Mali dates back more than 20 years. The absence of information on the current status of CL in Mali led us to conduct a cohort study in Kemena and Sougoula, two villages in Central Mali from which cases of CL have been recently diagnosed by Mali''s reference dermatology center in Bamako. In May 2006, we determined the baseline prevalence of Leishmania infection in the two villages using the leishmanin skin test (LST). LST-negative individuals were then re-tested over two consecutive years to estimate the annual incidence of Leishmania infection. The prevalence of Leishmania infection was significantly higher in Kemena than in Sougoula (45.4% vs. 19.9%; OR: 3.36, CI: 2.66–4.18). The annual incidence of Leishmania infection was also significantly higher in Kemena (18.5% and 17% for 2007 and 2008, respectively) than in Sougoula (5.7% for both years). These data demonstrate that the risk of Leishmania infection was stable in both villages and confirm the initial observation of a significantly higher risk of infection in Kemena (OR: 3.78; CI: 2.45–6.18 in 2007; and OR: 3.36; CI: 1.95–5.8 in 2008; P<0.005). The absence of spatial clustering of LST-positive individuals in both villages indicated that transmission may be occurring anywhere within the villages. Although Kemena and Sougoula are only 5 km apart and share epidemiologic characteristics such as stable transmission and random distribution of LST-positive individuals, they differ markedly in the prevalence and annual incidence of Leishmania infection. Here we establish ongoing transmission of Leishmania in Kemena and Sougoula, Central Mali, and are currently investigating the underlying factors that may be responsible for the discrepant infection rates we observed between them.
Trial Registration
ClinicalTrials.gov NCT00344084相似文献36.
Balla Sylla Karine Descroix Christophe Pain Cédric Gervaise Frank Jamois Laurent Legentil Caroline Nugier-Chauvin Richard Daniellou Vincent Ferrières 《Carbohydrate research》2010,345(10):1366-1370
It is known that 3-O-glycosylation of glucosidic acceptors bearing acyl groups in the 4 and 6 positions instead of a 4,6-O-benzylidene ring mainly affords α-glycosides. Described here is an unexpected stereochemical outcome for elongation at glucose O-3 of a β-d-Glcp-(1→3)-α-d-Manp disaccharide using peracetylated ethyl thioglucoside as a donor. This unexpected reaction was correlated with match-mismatch effects, as shown by efficient coupling of the same acceptor by a donor of l-configuration. 相似文献
37.
Massimiliano Papi Roberto Brunelli Lakamy Sylla Tiziana Parasassi Maurizio Monaci Giuseppe Maulucci Mauro Missori Giuseppe Arcovito Fulvio Ursini Marco De Spirito 《European biophysics journal : EBJ》2010,39(6):987-992
We have investigated the changes in the mechanical properties of the zona pellucida (ZP), a multilayer glycoprotein coat that
surrounds mammalian eggs, that occur after the maturation and fertilization process of the bovine oocyte by using atomic force
spectroscopy. The response of the ZP to mechanical stress has been recovered according to a modified Hertz model. ZP of immature
oocytes shows a pure elastic behavior. However, for ZPs of matured and fertilized oocyte, a transition from a purely elastic
behavior, which occurs when low stress forces are applied, towards a plastic behavior has been observed. The high critical
force necessary to induce deformations, which supports the noncovalent long interaction lifetimes of polymers, increases after
the cortical reaction. Atomic force microscopy (AFM) images show that oocyte ZP surface appears to be composed mainly of a
dense, random meshwork of nonuniformly arranged fibril bundles. More wrinkled surface characterizes matured oocytes compared
with immature and fertilized oocytes. From a mechanical point of view, the transition of the matured ZP membrane toward fertilized
ZP, through the hardening process, consists of the recovery of the elasticity of the immature ZP while maintaining a plastic
transition that, however, occurs with a much higher force compared with that required in matured ZP. 相似文献
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Ladawan Wasinpiyamongkol Sirilaksana Patramool Natthanej Luplertlop Pornapat Surasombatpattana Souleymane Doucoure François Mouchet Martial Séveno Franck Remoue Edith Demettre Jean‐Paul Brizard Patrick Jouin David G. Biron Frédéric Thomas Dorothée Missé 《Proteomics》2010,10(10):1906-1916
Mosquito‐transmitted pathogens pass through the insect's midgut (MG) and salivary gland (SG). What occurs in these organs in response to a blood meal is poorly understood, but identifying the physiological differences between sugar‐fed and blood‐fed (BF) mosquitoes could shed light on factors important in pathogens transmission. We compared differential protein expression in the MGs and SGs of female Aedes aegypti mosquitoes after a sugar‐ or blood‐based diet. No difference was observed in the MG protein expression levels but certain SG proteins were highly expressed only in BF mosquitoes. In sugar‐fed mosquitoes, housekeeping proteins were highly expressed (especially those related to energy metabolism) and actin was up‐regulated. The immunofluorescence assay shows that there is no disruption of the SG cytoskeletal after the blood meal. We have generated for the first time the 2‐DE profiles of immunogenic Ae. aegypti SG BF‐related proteins. These new data could contribute to the understanding of the physiological processes that appear during the blood meal. 相似文献
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