PubMed Health⌕ Search

Biomedical subjects

M M Riley

Publications and source records attributed to M M Riley.

3 recordsLinked to original sources
PubMed2000

Tumor necrosis factor-alpha and lipopolysaccharide enhance interferon-induced antichlamydial indoleamine dioxygenase activity independently.

In macrophages, interleukin-1 (IL-1) and lipopolysaccharide (LPS) enhance the antichlamydial effect of interferon-gamma (IFN-gamma) by increasing indoleamine 2,3-dioxygenase (IDO) activity in a dose-dependent manner. Our objectives were to characterize the antichlamydial effect of tumor necrosis factor-alpha (TNF-alpha) on IFN-induced IDO activity and to establish the relationship between LPS and TNF-alpha in IDO potentiation. TNF-alpha inhibited chlamydial growth in a dose-dependent manner only in IFN-treated macrophages. Furthermore, excess tryptophan reversed the effect of combined cytokine treatment, indicating that IDO alone was responsible for chlamydial inhibition. The promonocyte THP-1 cell line, previously used to model the effect of IL-1 on IDO mRNA expression, was treated with IFN-gamma and increasing concentrations of LPS or TNF-alpha. IDO mRNA was quantified by RT-PCR, and IDO activity was measured by HPLC at 24 and 48 h after treatment, respectively. Both LPS and TNF-alpha enhanced IDO activity and IDO mRNA expression, with maximal IDO induction at 100 ng/ml LPS or 5 ng/ml TNF-alpha. Anti-TNF-alpha failed to neutralize the effects of LPS treatment, and insufficient TNF-alpha or IL-1 was produced by LPS-treated THP-1 cells to account for the enhancing effect of LPS, indicating that the effect of LPS on IDO was independent of TNF-alpha and IL-1.

Adjuvants, Immunologic↗
PubMed1998

Congenital malformations in Victoria, Australia, 1983-95: an overview of infant characteristics.

OBJECTIVE: To provide an overview of the characteristics of Victorian infants born between 1983 and 1995 who are affected by one or more of 27 sentinel birth defects. METHODOLOGY: Using data on congenital malformations supplied to the Victorian Perinatal Data Collection Unit from multiple sources between 1983 and 1995, information was summarised for 25231 infants (born at 20 weeks or more) and 1566 terminations of pregnancy before 20 weeks' gestation. RESULTS: During the 13-year study period in Victoria, 3.2% of babies had at least one malformation. Congenital dislocation of the hip was the most common defect with a prevalence of 28.9 per 10000 pregnancies or 1/346. Increase in birth prevalence between 1983 and 1995 is greatest in obstructive defects of the renal pelvis, hypospadias and the trisomies 21,13 and 18. Nearly 50% of pregnancies affected by anencephaly were terminated before 20 weeks compared to 26% affected by spina bifida. The perinatal mortality of infants born at 20 weeks or more with congenital malformations is more than 10 times greater than that of infants without any malformations. Males are more at risk of being born with a malformation than females. Congenital malformations are more common in infants of multiple pregnancies and those of low birthweight. CONCLUSION: This large data collection is a valuable source of information for perinatal epidemiologists, for providers of prenatal diagnostic services and for the care of the disabled. In addition, the continued reporting and monitoring of birth defects will allow for targeted research that may lead to a better understanding of their aetiology.

Abnormalities, Multiple↗