Publications by authors named "Bich-Thuy L"

Objectives: The present study aims to investigate whether each coping style used by Vietnamese people living with infertility diagnosis is associated with specific types of infertility-related stress (IRS).

Methods: In this cross-sectional design study, 997 patients with primary infertility diagnosis from three hospitals and two clinics in three regions of Vietnam completed questionnaire that consisted of Fertility Problem Inventory, the Copenhagen Multi-Centre Psychosocial Infertility and other questions. Four different linear regression analyses were performed on four coping styles.

View Article and Find Full Text PDF

Emission from field burning of crop residue, a common practice in many parts of the world today, has potential effects on air quality, atmosphere and climate. This study provides a comprehensive size and compositional characterization of particulate matter (PM) emission from rice straw (RS) burning using both in situ experiments (11 spread field burning) and laboratory hood experiments (3 pile and 6 spread burning) that were conducted during 2003-2006 in Thailand. The carbon balance and emission ratio method was used to determine PM emission factors (EF) in the field experiments.

View Article and Find Full Text PDF

In this study, we investigated the expression of CD5 molecules on the surface of mature human peripheral B lymphocytes. Human CD5+ B cells were isolated from tonsils and peripheral blood. Their terminal differentiation into plasma cells was induced with IL-2.

View Article and Find Full Text PDF

In this study, using interleukin-2 and gamma interferon, we first induced the differentiation into plasma cells of primary chronic lymphoid leukemic B cells from patients whose T cells failed to produce interleukin-2. We next demonstrated that these malignant primary B lymphocytes (i.e.

View Article and Find Full Text PDF

We have reported that one of the currently known receptors for interleukin-2 (IL-2), the p70 protein, is constitutively expressed on resting T lymphocyte membrane. We demonstrated that exposure of these cells to high concentrations of IL-2 resulted in the transcription of genes whose expression occurred early during cell activation such as cmyc, cmyb protooncogenes, and the Tac gene itself. IL-2 is thought to exert its biological effects by binding to its high-affinity receptors on cell membrane.

View Article and Find Full Text PDF

We have developed a system to study transcriptional regulation of the lambda immunoglobulin gene in a natural setting -- lambda light chain producing lymphoid cells. This assay system has allowed the detection of an enhancer element located 3' of the lambda gene coding sequence. The enhancer can stimulate transcription from the lambda promoter as well as from other immunoglobulin and unrelated promoters.

View Article and Find Full Text PDF

We show in this report that the transcription induced by interleukin-2 or pokeweed mitogens of the kappa MOPC 41 immunoglobulin light-chain gene transfected into primary human or murine B lymphocytes initiates from a previously unobserved start site about 26 base pairs upstream of the start site used in myeloma cell lines.

View Article and Find Full Text PDF

High concentrations of interleukin 2 (IL 2) were shown to produce a delayed but pronounced proliferation of purified resting T cells in the apparent absence of other activation signals. Because these stimulatory effects of IL 2 occurred in the absence of detectable Tac+ cells, the possibility that IL 2 might be initially interacting with an IL 2 binding protein distinct from the Tac protein was studied. Chemical cross-linking studies with 125I-IL 2 revealed the presence of an IL 2 binding protein distinct from the Tac protein on the surface of these unstimulated T cells.

View Article and Find Full Text PDF

Enhancers are DNA sequences that stimulate transcription from eukaryotic promoters. This stimulatory effect can be exerted over large distances and from a position either 5' or 3' of a promoter. Enhancers have been found in the genomes of many viruses, and in some cellular genes such as those encoding immunoglobulin heavy chain and kappa light chain.

View Article and Find Full Text PDF

Human peripheral blood mononuclear cells as well as T-cell-enriched or T-cell-depleted populations were found to proliferate in response to recombinant interleukin-2 (IL-2) in vitro in the absence of a lectin preactivation signal. This proliferative response was detected at Day 2, peaked at Day 5, and was dependent on the concentration of IL-2 used. At the initiation of culture, these cells did not appear to be activated as determined by the expression of Tac antigens.

View Article and Find Full Text PDF

The relative proportions of cells synthesizing the three major Ig classes or one of the four IgG subclasses in cultures stimulated with pokeweed mitogen (PWM) or Nocardia-delipidated cell mitogen (NDCM) were investigated. In cultures of human peripheral blood mononuclear cells (PB MNC) stimulated with PWM, the number of IgG-containing cells (CC) was higher than the number of IgM-CC, and a substantial number of IgA-CC was found. Conversely, in NDCM-stimulated PB MNC cultures IgM-CC outnumbered IgG-CC and only few IgA-CC were detected.

View Article and Find Full Text PDF

The regulation of IgG subclass production by polyclonally activated human B cells was investigated by using two systems previously shown to selectively suppress the generation of IgG-containing cells (CC) but not that of IgMCC or IgACC. The first one involved a brief exposure of peripheral blood mononuclear cells (PBMNC) to heat-aggregated human IgG (Agg-IgG) followed by repeated washings and culture with untreated autologous PBMNC. The second one was achieved by addition of human IgG-binding factor(s) (IgGBF) prepared by affinity chromatography from supernatants of unstimulated PBMNC.

View Article and Find Full Text PDF

Human IgG binding factors (IgG BF) were prepared by immunopurification on IgG immunosorbents from cell-free supernatants of unstimulated peripheral blood mononuclear cells (PB MNC). The suppressive effects of IgG BF was studied using PB MNC stimulated by pokeweed mitogen or by nocardia delipidated cell mitogen. At the end of the culture three parameters of B cell activation were measured: (1) the numbers of IgM-, IgG-, or IgA-containing cells (CC) using direct immunofluorescence, (2) the numbers of IgM, IgG, or IgA plaque-forming cells (PFC) using a Protein A hemolytic plaque assay, and (3) the concentrations of IgM, IgG, or IgA in culture supernatants using an enzyme-linked immunosorbent assay.

View Article and Find Full Text PDF

Receptors for the Fc part of IgG were isolated by affinity chromatography from supernatants of unstimulated human lymphocytes or polymorphonuclear neutrophils. When added to cultures stimulated by polyclonal activators, these soluble receptors selectively depressed the maturation of B lymphocytes into IgG-producing cells, whereas the number of IgM-producing cells was either increased or unchanged. The number of IgA-containing cells was not changed.

View Article and Find Full Text PDF

During short incubation in serum-free medium, polymorphonuclear neutrophils (PMN) release soluble material that can be characterized as receptors for Fc IgG (Fc gamma R) on the following evidence: it agglutinates erythrocyte-IgG antibody (EAG) complexes, it prevents the binding of EAG to EAG-rosette-forming cells, and it binds to EAG-rosette-forming cells after modulation of their Fc gamma R, allowing the formation of 'passive' rosettes. These Fc gamma R were isolated by affinity chromatography on sepharose 4B-IgG. This material was shown to interfere with the differentiation of peripheral blood B cells into Ig-secreting cells in cultures stimulated by pokeweed (PWM) or Nocardia opaca (NOC) extracts.

View Article and Find Full Text PDF

In vitro human plasma cell generation induced by both T-dependent (PWM) and T-independent (NWSM) mitogens was found to be suppressed by peripheral blood lymphocytes preincubated with human aggregated IgG. T cells, but not B lymphocytes, were able to mediate the suppressive activity; since aggregated (Fab)'2 fragments were found unable to generate suppressor cells, it was concluded that the suppressor cell was a T lymphocyte bearing Fcgamma receptors. These cells appeared to be largely radiosensitive.

View Article and Find Full Text PDF

Mononuclear cells from eighty-seven human tonsils and fourteen adenoids were examined for T and B cells and their subpopulations. Forty six percent of the tonsil cells were killed in the presence of C by an antiserum specific for T cells and 41.7% were able to form E rosettes.

View Article and Find Full Text PDF