24 research outputs found
Dendritic cells in uninfected infants born to hepatitis B virus-positive mothers
Plasmacytoid dendritic cells (pDCs) play a central role in antiviral immunity, detecting viruses via Toll-like receptors (TLR) and producing in response vast amounts of type I interferons (IFNs). Hepatitis B virus (HBV) causes chronic infection after vertical transmission. This study investigated whether an HBV-infected maternal environment might influence DC numbers and pDC function in uninfected infants. Blood was collected from inactive HBsAg carrier and control mothers and their infants at birth and 1 and 6 months of age. HBV DNA was measured in maternal and neonatal perinatal sera using real-time PCR. The circulating frequencies of myeloid DCs (mDCs) and pDCs were determined in the babies by flow cytometry. Peripheral blood mononuclear cells (PBMCs) and cord blood pDCs were stimulated with resiquimod, and alpha interferon (IFN-α) production and the pDC phenotype were assessed. The effect of the common-cold virus, rhinovirus (RV), on resiquimod stimulation was also determined. HBV DNA was detected in 62.3% of the mothers and 41% of their infants. DC numbers and pDC functions were similar between subjects and controls and were not correlated with maternal or neonatal viremia. RV infection did not induce pDC maturation until the age of 6 months, and it reduced TLR7-dependent resiquimod-induced IFN-α production similarly in both groups. Although the DC system is immature at birth, DCs of uninfected neonates of HBV-positive mothers are competent to initiate and maintain T-cell responses. RV is a weak inducer of IFN-α production until the age of 6 months and inhibits IFN-α responses triggered by the TLR7 pathway. Copyright © 2010, American Society for Microbiology. All Rights Reserved
HBV viremia in newborns of HBsAg(+) predominantly Caucasian HBeAg(-) mothers
Background: Hepatitis B virus infection is an important public health problem worldwide and eliminating mother-to-infant transmission is important to decrease the prevalence of chronic HBV-infection. Although, immunoprophylaxis given at birth largely prevents mother-to-infant transmission, perinatal HBV viremia has been reported in HBsAg(-) newborns born mainly to HBeAg(+) women in endemic areas. Objectives: To examine the incidence of perinatal HBV viremia in newborns of HBsAg(+) predominantly HBeAg(-) mothers. Study design: Peripheral blood was obtained at birth from 109 HBsAg(+) mothers and their newborns before the administration of active-passive immunoprophylaxis. Infants were prospectively followed and appropriately vaccinated. Results: Although most (92.7%) of the HBsAg(+) mothers were HBeAg(-), 73.4% had detectable HBV viremia. Neonatal viremia was detected in 3/8 (37.5%) and 24/101 (23.8%) newborns of HBeAg(+) and HBeAg(-) mothers, respectively (p= 0.386). However, HBV-DNA levels were significantly higher in newborns of HBeAg(+) mothers (p= 0.025). No child developed chronic HBV infection, but one child had evidence of subclinical hepatitis. Conclusions: Although the clinical significance of low viremia levels in almost one in four newborns of HBsAg(+) mothers in a low endemicity area is unclear, it may enhance our understanding of HBV mother-to-infant transmission. © 2010 Elsevier B.V
Development of a European consensus from dentists, dental hygienists and physicians on a standard for oral health care in care-dependent older people: An e-Delphi study
Objectives: This study aimed to obtain a consensus on oral health policy, access to dental care, oral hygiene measures and training levels. Background: Poor oral health is widespread in care-dependent older people, but no consensus for a minimum standard of oral health care exists yet. Methods: The e-Delphi approach was applied to a selected panel of interdisciplinary experts. Data analysis was based on three measurements: (a) ≥70% of experts’ opinion fall into category “agree or strongly agree,” (b) median score on the 5-point Likert scale ≥4, (c) interquartile range ≤1. Results: A total of 31 experts from 17 European countries participated in this survey. Agreement was achieved for a compulsory dental examination when an elder is admitted to a long-term care (LTC) facility. Older people should brush their teeth twice/day and regularly clean interproximal spaces and oral mucosa. Dentures should be rinsed after meals and cleaned twice/day. The use of denture cleansing tablets was considered necessary. Dentures should be removed before sleeping and stored dry. A 5000 ppm fluoride toothpaste should be applied daily in elder with high caries risk. A short report on the oral health status of the elder should be included in the geriatric assessment. All experts concluded that the knowledge and the training in oral health care for caregivers and family members of care-dependent older people were imperative. Conclusions: Using the e-Delphi method, multidisciplinary healthcare professionals from different countries agreed on certain cardinal recommendations for a standard oral health care for care-dependent older people. © 2020 Gerodontology Association and John Wiley & Sons Lt