PubMed Health⌕ Search

Biomedical subjects

S Pongcharoen

Publications and source records attributed to S Pongcharoen.

5 recordsLinked to original sources

Interleukin-17 expression in the human placenta.

Interleukin (IL)-17 is a proinflammatory cytokine with pleiotropic activities including inducing neovascularization and production of proangiogenic molecules. As pregnancy outcome depends on the balance of Th1-like/Th2-like cytokines and an increased blood supply to the fetoplacental unit, the expression of IL-17 mRNA and protein in human placental tissues was investigated. IL-17 mRNA was expressed by purified cytokeratin-positive term placental trophoblast cells, HLA-G+ extravillous trophoblast cells and placental macrophages (Hofbauer cells). IL-17 localized in both cyto- and syncytiotrophoblasts of normal term pregnancy, spontaneous miscarriage and in molar pregnancy. In spontaneous miscarriage and molar pregnancy extravillous trophoblast cells were consistently immunoreactive for IL-17. IL-17 expression in human placenta may play a key role in angiogenesis and/or immunoregulation in the establishment of pregnancy.

Adolescent↗

Placental Fas and Fas ligand expression in normal early, term and molar pregnancy.

To clarify the Fas and Fas-ligand status of normal and molar trophoblast, the expression of Fas and FasL by placental trophoblast populations in partial and complete hydatidiform moles was compared with that in normal first trimester and term pregnancies using an avidin-biotin peroxidase technique on frozen and formalin-fixed paraffin-embedded placental tissues with both monoclonal and polyclonal antibodies. The TUNEL technique was used to detect apoptotic cells in the same tissues. The immunoreactivity for Fas and Fas-ligand was comparable with both monoclonal and polyclonal antibodies on frozen as well as paraffin-embedded sections. In normal early and molar pregnancy there was strong FasL expression by villous cytotrophoblast and syncytiotrophoblast. However, there were significant differences in FasL expression by trophoblast subpopulations in both early and term normal pregnancy and between the same trophoblast subpopulation at different gestations, with FasL staining generally being weaker at term. Strong FasL staining by cytotrophoblast cells in the distal parts of cell columns contrasted with unstained cytotrophoblast in the proximal part of columns. Distinct trophoblast subpopulations in partial hydatidiform mole also differentially expressed FasL with reduced FasL expression in proliferating syncytiotrophoblast. In contrast there was no differential FasL expression in complete hydatidiform mole, all trophoblast subpopulations strongly expressing FasL. Unlike the differential expression of FasL there were no differences in Fas expression by trophoblast populations in normal early or term placental tissues. Fas expression was reduced in villous cytotrophoblast at term. Differential expression of Fas by different trophoblast subpopulations was noted in partial and complete hydatidiform mole. In complete mole villous cytotrophoblast and syncytiotrophoblast stained strongly compared with proliferating trophoblast. Using TUNEL labelling apoptosis was rarely detected in placental trophoblast. Differential Fas and FasL expression by trophoblast subpopulations in normal and pathological pregnancy does not appear to be related to apoptosis of trophoblast.

Adult↗

No evidence for apoptosis of decidual leucocytes in normal and molar pregnancy: implications for immune privilege.

Complete hydatidiform moles are totally paternally derived and represent complete allografts that might be expected to provoke maternal immune rejection. Our previous and other studies have shown expression of Fas by increased numbers of activated decidual CD4(+) T cells in both complete and partial molar pregnancy as well as increased FasL(+) expression by molar trophoblasts compared with trophoblasts in normal pregnancies. As the Fas/FasL system represents a major apoptotic pathway that can play a role in immune privilege, the aim of this study was to investigate whether apoptosis of decidual immune cells, particularly T cells, could be responsible for maternal immune tolerance in molar pregnancy. Using terminal deoxynucleotidyl transferase (TdT)-mediated nick end-labelling (TUNEL), a significant increase in TUNEL(+) cells was demonstrated in decidua associated with partial (P = 0.0052) and complete (P = 0.0096) hydatidiform mole compared with normal early pregnancy. Co-labelling immunoperoxidase studies showed that the TUNEL(+) cells in both normal and molar pregnancies were not activated CD45RO(+) immune cells, CD3(+) T cells, CD56(+) uterine natural killer (NK) cells or CD14(+) CD68(+) macrophages. Double immunohistochemical labelling with antiactive caspase-3 and leucocyte markers confirmed the lack of leucocyte apoptosis. Double immunostaining with anticytokeratin to detect trophoblast and M30 CytoDeath, which detects a neoepitope of cytokeratin 18 revealed after caspase-mediated cleavage, revealed apoptotic extravillous trophoblast cells within decidual tissue. We conclude that there is no evidence that apoptosis of decidual leucocytes plays a role in maintaining maternal tolerance in either normal or molar pregnancy.

Antigens, CD↗

Vitamin K prophylaxis in the neonates by oral route with different dosages.

This paper evaluated the effect of VKP in the neonates by oral route with different dosages compared to the standard parenteral route giving a single dose at birth. Two hundred and thirty-six healthy, breast-fed infants were divided into 4 groups receiving vitamin K1 1 mg intramuscularly and 2, 3, 5 mg orally during 2-4 hours after birth. The vitamin K dependent clotting factors were measured by the thrombotest at the age of 2 weeks and 4-6 weeks. The result showed no statistical differences among these 4 groups regarding the mean prothrombin complex level and the number of PC deficient subjects. Vitamin K prophylaxis in the newborn babies by 2 mg oral route would be benefit and can be applied routinely as well as 1 mg parenteral route to prevent both HDN and APCD syndrome particularly in breast fed infants. The routine practice of giving vitamin K1 prophylaxis 2 mg orally or 0.5-1 mg intramuscularly should be recommended to all newborn infants. Giving VKP by oral route is practical for developing countries because of simple way of administration, low cost, low toxicity, as well as high efficacy.

Administration, Oral↗