4,925 research outputs found
Transmission of Foot-and-Mouth Disease Virus during the Incubation Period in Pigs.
Understanding the quantitative characteristics of a pathogen's capability to transmit during distinct phases of infection is important to enable accurate predictions of the spread and impact of a disease outbreak. In the current investigation, the potential for transmission of foot-and-mouth disease virus (FMDV) during the incubation (preclinical) period of infection was investigated in seven groups of pigs that were sequentially exposed to a group of donor pigs that were infected by simulated-natural inoculation. Contact-exposed pigs were comingled with infected donors through successive 8-h time slots spanning from 8 to 64 h post-inoculation (hpi) of the donor pigs. The transition from latent to infectious periods in the donor pigs was clearly defined by successful transmission of foot-and-mouth disease (FMD) to all contact pigs that were exposed to the donors from 24 hpi and later. This onset of infectiousness occurred concurrent with detection of viremia, but approximately 24 h prior to the first appearance of clinical signs of FMD in the donors. Thus, the latent period of infection ended approximately 24 h before the end of the incubation period. There were significant differences between contact-exposed groups in the time elapsed from virus exposure to the first detection of FMDV shedding, viremia, and clinical lesions. Specifically, the onset and progression of clinical FMD were more rapid in pigs that had been exposed to the donor pigs during more advanced phases of disease, suggesting that these animals had received a higher effective challenge dose. These results demonstrate transmission and dissemination of FMD within groups of pigs during the incubation period of infection. Furthermore, these findings suggest that under current conditions, shedding of FMDV in oropharyngeal fluids is a more precise proxy for FMDV infectiousness than clinical signs of infection. These findings may impact modeling of the propagation of FMD outbreaks that initiate in pig holdings and should be considered when designing FMD control strategies
Switching to nevirapine (NVP) significantly increases high-density lipoprotein cholesterol (HDL-C) in treatment-experienced patients (NEVICOR study)
The role of Prenatal Care and Social Risk Factors in the relationship between immigrant status and neonatal morbidity: A retrospective cohort study
Background and Aim Literature evaluating association between neonatal morbidity and immigrant status presents contradictory results. Poorer compliance with prenatal care and greater social risk factors among immigrants could play roles as major confounding variables, thus explaining contradictions. We examined whether prenatal care and social risk factors are confounding variables in the relationship between immigrant status and neonatal morbidity. Methods Retrospective cohort study: 231 pregnant African immigrant women were recruited from 2007–2010 in northern Spain. A Spanish population sample was obtained by simple random sampling at 1:3 ratio. Immigrant status (Spanish, Sub-Saharan and Northern African), prenatal care (Kessner Index adequate, intermediate or inadequate), and social risk factors were treated as independent variables. Low birth weight (LBW < 2500 grams) and preterm birth (< 37 weeks) were collected as neonatal morbidity variables. Crude and adjusted odds ratios (OR) were estimated by unconditional logistic regression with 95% confidence intervals (95% CI). Results Positive associations between immigrant women and higher risk of neonatal morbidity were obtained. Crude OR for preterm births in Northern Africans with respect to nonimmigrants was 2.28 (95% CI: 1.04–5.00), and crude OR for LBW was 1.77 (95% CI: 0.74–4.22). However, after adjusting for prenatal care and social risk factors, associations became protective: adjusted OR for preterm birth = 0.42 (95% CI: 0.14–1.32); LBW = 0.48 (95% CI: 0.15–1.52). Poor compliance with prenatal care was the main independent risk factor associated with both preterm birth (adjusted OR inadequate care = 17.05; 95% CI: 3.92–74.24) and LBW (adjusted OR inadequate care = 6.25; 95% CI: 1.28–30.46). Social risk was an important independent risk factor associated with LBW (adjusted OR = 5.42; 95% CI: 1.58– 18.62). Conclusions Prenatal care and social risk factors were major confounding variables in the relationship between immigrant status and neonatal morbidity
The Influence of Secondhand Smoke Exposure on Birth Outcomes in Jordan
This study investigates how secondhand smoke (SHS) exposure influences neonatal birth weight in Jordan, a country with high smoking prevalence. The findings revealed that as the average number of SHS exposure hours per week increased in the second trimester, the neonatal birth weight decreased while holding all covariates constant. Women who reported a higher average number of SHS exposure hours per week from work in the second trimester, home in the third trimester, and outside in the third trimester were at greater risk for having a low birth weight neonate than women who reported a lower average number of SHS exposure hours
Existence of positive solutions to discrete second-order boundary value problems with indefinite weight
Bright Stars and Recent Star Formation in the Irregular Magellanic Galaxy NGC2366
The stellar content of the Im galaxy NGC 2366 is discussed on the basis of
CCD BVR photometry. The three brightest blue and red stars have been used to
estimate its distance, obtaining a balue of 2.9 Mpc. The spatial distribution
of the young stellar population is discussed in the light of the integrated
color indices and the color-magnitude diagrams of different zones of the
galaxy. A generalized star formation burst seems to have taken place about 50
Myr ago. The youngest stars are preferentially formed in the South-West part of
the bar, where the giant HII complex NGC 2363 is located, being younger and
bluer. The bar seems to play a role favouring star formation in one of its
extremes. Self-propagation however, does not seem to be triggering star
formation at large scale. A small region, populated by very young stars has
also been found at the East of the galaxy.Comment: Astronomical Journal, accepted. This is a uuencoded, compressed, tar
file (102 Kbytes) of 1 text, 1 table postscript files. Figures are retrieved
as a separate file. One single file with all figures and tables (552Kb) also
available from http://www.ast.cam.ac.uk/~etelles/astronomy.htm
Specificities of a chemically modified laccase from trametes hirsuta on soluble and cellulose-bound substrates
Laccases could prevent fabrics and
garments from re-deposition of dyes during
washing and finishing processes by degrading the solubilized dye. However, laccase action must be restricted to solubilized dye molecules thereby
avoiding decolorization of fabrics. Chemical
modification of enzymes can provide a powerful tool to change the adsorption behaviour of enzymes on water insoluble polymers. Polyethylene glycol (PEG) was covalently attached onto a laccase from Trametes hirsuta. Different molecular
weights of the synthetic polymer were tested
in terms of adsorption behaviour and retained
laccase activity. Covalent attachment of PEG
onto the laccase resulted in enhanced enzyme
stability while with increasing molecular weight of attached PEG the substrate affinity for the laccase conjugate decreased. The activity of the modified laccases on fibre bound dye was drastically reduced decreasing the adsorption of the enzyme on various fabrics. Compared to the 5 kDa PEG laccase conjugate (K/S value 47.60
Myofascial trigger points in cluster headache patients: a case series
Active myofascial trigger points (MTrPs) have been found to contribute to chronic tension-type headache and migraine. The purpose of this case series was to examine if active trigger points (TrPs) provoking cluster-type referred pain could be found in cluster headache patients and, if so, to evaluate the effectiveness of active TrPs anaesthetic injections both in the acute and preventive headache's treatment. Twelve patients, 4 experiencing episodic and 8 chronic cluster headache, were studied. TrPs were found in all of them. Abortive infiltrations could be done in 2 episodic and 4 chronic patients, and preemptive infiltrations could be done in 2 episodic and 5 chronic patients, both kind of interventions being successful in 5 (83.3%) and in 6 (85.7%) of the cases respectively. When combined with prophylactic drug therapy, injections were associated with significant improvement in 7 of the 8 chronic cluster patients. Our data suggest that peripheral sensitization may play a role in cluster headache pathophysiology and that first neuron afferent blockade can be useful in cluster headache management
Antiviral mode of action of bovine dialyzable leukocyte extract against human immunodeficiency virus type 1 infection
<p>Abstract</p> <p>Background</p> <p>Bovine dialyzable leukocyte extract (bDLE) is derived from immune leukocytes obtained from bovine spleen. DLE has demonstrated to reduce transcription of Human Immunodeficiency Virus Type 1 (HIV-1) and inactivate the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway. Therefore, we decided to clarify the mode of antiviral action of bDLE on the inhibition of HIV-1 infection through a panel of antiviral assays.</p> <p>Results</p> <p>The cytotoxicity, HIV-1 inhibition activity, residual infectivity of bDLE in HIV-1, time of addition experiments, fusion inhibition of bDLE for fusogenic cells and the duration of cell protection even after the removal of bDLE were all assessed in order to discover more about the mode of the antiviral action.</p> <p>HIV-1 infectivity was inhibited by bDLE at doses that were not cytotoxic for HeLa-CD4-LTR-β-gal cells. Pretreatment of HIV-1 with bDLE did not decrease the infectivity of these viral particles. Cell-based fusion assays helped to determine if bDLE could inhibit fusion of Env cells against CD4 cells by membrane fusion and this cell-based fusion was inhibited only when CD4 cells were treated with bDLE. Infection was inhibited in 80% compared with the positive (without EDL) at all viral life cycle stages in the time of addition experiments when bDLE was added at different time points. Finally, a cell-protection assay against HIV-1 infection by bDLE was performed after treating host cells with bDLE for 30 minutes and then removing them from treatment. From 0 to 7 hours after the bDLE was completely removed from the extracellular compartment, HIV-1 was then added to the host cells. The bDLE was found to protect the cells from HIV-1 infection, an effect that was retained for several hours.</p> <p>Conclusions</p> <p>bDLE acted as an antiviral compound and prevented host cell infection by HIV-1 at all viral life cycle stages. These cell protection effects lingered for hours after the bDLE was removed. Interestingly, bDLE inhibited fusion of fusogenic cells by acting only on CD4 cells. bDLE had no virucidal effect, but could retain its antiviral effect on target cells after it was removed from the extracellular compartment, protecting the cells from infection for hours.</p> <p>bDLE, which has no reported side effects or toxicity in clinical trials, should therefore be further studied to determine its potential use as a therapeutic agent in HIV-1 infection therapy, in combination with known antiretrovirals.</p
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