Search results for "General Immunology and Microbiology"
showing 10 items of 784 documents
Host-based divergence in populations of the pea aphid: insights from nuclear markers and the prevalence of facultative symbionts.
2003
In North America, the pea aphid Acyrthosiphon pisum encompasses ecologically and genetically distinct host races that offer an ideal biological system for studies on sympatric speciation. In addition to its obligate symbiont Buchnera, pea aphids harbour several facultative and phylogenetically distant symbionts. We explored the relationships between host races of A. pisum and their symbiotic microbiota to gain insights into the historical process of ecological specialization and symbiotic acquisition in this aphid. We used allozyme and microsatellite markers to analyse the extent of genetic differentiation between populations of A. pisum on pea, alfalfa and clover in France. In parallel, we…
Does predation maintain eyespot plasticity in Bicyclus anynana?
2004
The butterfly Bicyclus anynana exhibits phenotypic plasticity involving the wet-season phenotype, which possesses marginal eyespots on the ventral surface of the wings, and the dry-season form, which lacks these eyespots. We examined the adaptive value of phenotypic plasticity of B. anynana in relation to the defence mechanisms of crypsis and deflection. We assessed the visibility differences between spotless and spotted butterflies against backgrounds of brown (dry season) or green (wet season) leaves. Spotless butterflies were highly cryptic and less predated by adult bird predators than were spotted ones when presented against brown leaf litter. However, the advantage of crypsis disappea…
Coexpression of IL-6 and soluble IL-6R causes nodular regenerative hyperplasia and adenomas of the liver
1998
Studies with tumor necrosis factor p55 receptor- and interleukin-6 (IL-6)-deficient mice have shown that IL-6 is required for hepatocyte proliferation and reconstitution of the liver mass after partial hepatectomy. The biological activities of IL-6 are potentiated when this cytokine binds soluble forms of its specific receptor subunit (sIL-6R) and the resulting complex interacts with the transmembrane signaling chain gp130. We show here that double transgenic mice expressing high levels of both human IL-6 and sIL-6R under the control of liver-specific promoters spontaneously develop nodules of hepatocellular hyperplasia around periportal spaces and present signs of sustained hepatocyte prol…
Amplitude, Latency, and Peak Velocity in Accommodation and Disaccommodation Dynamics
2017
The aim of this work was to ascertain whether there are differences in amplitude, latency, and peak velocity of accommodation and disaccommodation responses when different analysis strategies are used to compute them, such as fitting different functions to the responses or for smoothing them prior to computing the parameters. Accommodation and disaccommodation responses from four subjects to pulse changes in demand were recorded by means of aberrometry. Three different strategies were followed to analyze such responses: fitting an exponential function to the experimental data; fitting a Boltzmann sigmoid function to the data; and smoothing the data. Amplitude, latency, and peak velocity of …
Sociodemographic and psychological correlates of COVID-19 vaccine hesitancy and resistance in the young adult population in Italy.
2021
Background: Previous research has shown that young adults are more hesitant/resistant to COVID-19 vaccine uptake than older age groups, although the factors underlying this tendency are still under debate. The current study aimed to identify the sociodemographic and psychological correlates of vaccine hesitancy and resistance among young adults (18–40 years) during the nationwide COVID-19 vaccination campaign in Italy, the first country after China being hit by the pandemic and which suffered a large number of fatalities. Methods: This is a cross-sectional, web-based study conducted in Italy using an ISO-certified international survey company (respondi.com). Data were collected on 1200 part…
Does more favourable handling of the cerebrospinal fluid increase the diagnostic sensitivity of Borrelia burgdorferi sensu lato-specific PCR in Lyme …
2017
Tests for direct detection of Borrelia burgdorferi sensu lato (Bb) in Lyme neuroborreliosis (LNB) are needed. Detection of Bb DNA using PCR is promising, but clinical utility is hampered by low diagnostic sensitivity. We aimed to examine whether diagnostic sensitivity can be improved by the use of larger cerebrospinal fluid (CSF) volumes and faster handling of samples.Patients who underwent CSF examination for LNB were included. We collected two millilitres of CSF for PCR analysis, extracted DNA from the pellets within 24 h and analysed the eluate by two real-time PCR protocols (16S rRNA and OspA). Patients who fulfilled diagnostic criteria for LNB were classified as LNB cases and the rest …
Safety and immunogenicity of RIX4414 live attenuated human rotavirus vaccine in adults, toddlers and previously uninfected infants
2003
Abstract A live attenuated human rotavirus (HRV) vaccine, strain RIX4414, was tested sequentially in adults, previously infected toddlers, and previously uninfected infants. A single dose was given to adults and toddlers and found well tolerated. Next, a dose ranging (three different viral concentrations) safety and immunogenicity study was conducted in rotavirus IgA antibody negative infants (N=192), who received two doses of RIX4414 vaccine or placebo at 2 and 4 months of age. No side effects were seen after vaccination. Specifically, administration of RIX4414 vaccine was not temporally associated with fever, diarrhea, or increase in liver transaminases. Rotavirus IgA seroconversion range…
Chronic Intestinal Infection due to Subgenus F Type 40 Adenovirus in a Patient with AIDS
1997
A case of chronic intestinal infection due to adenovirus type 40 lasting for 13 months in a patient with AIDS is described. Adenovirus particles were detected by electron microscopy in biopsy samples taken from the duodenum 3 months after the onset of diarrhoea. The virus was identified as adenovirus type 40 in stool samples by ELISA monoclonal antibodies to adenovirus group antigen (MAd-g2) and types 40 and 41 (MA 40-1 and MA 41-1). No other enteropathogens were found. These data support a causal relationship between adenovirus 40 and the gastrointestinal symptoms of the patient. This is the first reported case of intestinal infection caused by adenovirus type 40 in a patient with AIDS.
The Perception of Psychosocial Risks and Work-Related Stress in Relation to Job Insecurity and Gender Differences: A Cross-Sectional Study
2018
Introduction. The perception of psychosocial risks exposes workers to develop work-related stress. Recently the attention of scientific research has focused on a psychosocial risk already identified as “job insecurity” that regards the “overall concern about the continued existence of the job in the future” and that also depends on worker’s perception, different for each gender. Aim of the Study. The aim of this cross sectional study is to show if job insecurity, in the form of temporary contracts, can influence the perception of psychosocial risks and therefore increase worker’s vulnerability to work-related stress and how the magnitude of this effect differs between genders. Materials and…
Immunogenicity and safety of a nine-valent human papillomavirus vaccine in women 27–45 years of age compared to women 16–26 years of age: An open-lab…
2021
Abstract: Background: Efficacy of the nine-valent human papillomavirus (9vHPV; HPV types 6/11/16/18/31/33/45/52/58) vaccine was demonstrated in a phase 3 study in women 16 & ndash;26 years of age. We present a phase 3 immunogenicity and safety study of the 9vHPV vaccine in women 27 & ndash;45 versus 16 & ndash;26 years of age. Methods: This international, open-label study (NCT03158220) was conducted in women 16 & ndash;45 years of age. Participants (16 & ndash;26 years, n = 570 and 27 & ndash;45 years, n = 642) received a three-dose 9vHPV vaccination regimen (day 1, month 2, month 6). Month 7 geometric mean titers (GMTs) and seroconversion percentages to anti-HPV 6/11/16/18/31/33/45/52/58 w…