Search PubMed⌕ Search

Biomedical subjects

J W Chang

Publications and source records attributed to J W Chang.

82 records · Page 5Linked to original sources
PubMed1986

[Cultivation of urologic and male genital tumor cells].

Thirty specimens from 30 patients with urologic and male genital system tumors were cultured. Eighteen (60%) showed initial cell growth. Four (13%) were successful in primary culture. In a renal cell carcinoma and a bladder transitional cell carcinoma, the subcultures were successful after the primary culture. In eight months, having transferred the former for twelve generations and the latter for twenty-seven generations, these two cell lines are established. The morphological characters of the cultured cells, eradication of fibroblasts, conditions of culture and prevention of contamination are discussed.

Carcinoma, Renal Cell↗
PubMedDate not supplied

Prostaglandin G/H synthase-2 (cyclooxygenase-2) mRNA expression is decreased in Alzheimer's disease.

Recent evidence suggests that the use of nonsteroidal anti-inflammatory drugs (NSAIDS) is beneficial for therapy or prevention of Alzheimer's disease (AD). The major anti-inflammatory action of NSAIDS is to inhibit prostaglandin G/H synthase-2 (PGHS-2), the first committed enzymatic step for prostaglandin biosynthesis. We have previously shown that PGHS-2 message is induced by Interleukin-1 beta and other inflammatory mediators in primary cultures of rodent astrocytes. To determine whether similar elevations of PGHS-2 occur as part of the gliosis in AD, we quantified PGHS-2 mRNA levels in control and AD brain by Northern hybridization analysis. To our surprise we found that PGHS-2 mRNA levels were reduced threefold in AD neocortex relative to control brain tissue. In contrast, levels were not reduced in putamen, an area that is relatively spared in AD. To localize PGHS-2 mRNA production in control and AD brain, sections of neocortex and hippocampus were hybridized with a 35S-labeled riboprobe for human PGHS-2 followed by immunocytochemistry with antibodies against neuron specific enolase (NSE) or glial fibrillary acidic protein (GFAP). Our findings indicate that PGHS-2 message is primarily localized to cells that stain for NSE rather than GFAP. Furthermore, in the three cases we examined, PGHS-2 hybridization per neuron appeared to be reduced in AD. Thus, the decrease we observe in overall PGSH-2 mRNA levels is likely to reflect both the known decline in numbers of neurons in AD as well as a lowered capacity for neuronal synthesis of PGHS-2, perhaps due to dysfunction or a loss of synaptic input.

Aged↗
PubMedDate not supplied

Two-dimensional gel analysis of secreted proteins induced by interleukin-1 beta in rat astrocytes.

Interleukin-1 beta (IL-1 beta) is a pro-inflammatory cytokine produced in the brain by endogenous microglial cells responding to injury. Levels of IL-1 beta are elevated in several neurodegenerative disorders, including Alzheimer's disease. IL-1 beta, which can act as a mitogen for astrocytes, also elicits the expression and secretion of multiple factors and paracrine 'second messengers' such as other cytokines, nerve growth factor, prostaglandins and nitric oxide that may in turn modulate neuronal and glial responses to injury. Utilizing giant, high-resolution two-dimensional gel electrophoresis, we have sought to more fully define the potential range of protein mediators that are secreted by astrocytes treated with IL-1 beta. In cultured rat astrocytes, we observe dramatic increases in the secretion of eight different protein species after 24 h of treatment with human recombinant IL-1 beta (1 U/ml). Seven of the proteins are also induced by tumor necrosis factor-alpha or basic fibroblast growth factor. Based on immunoprecipitation with specific antisera, we have identified three of these proteins as plasminogen activator inhibitor type-1, ceruloplasmin, and complement component C3. The identities of the other proteins, including the IL-1 beta-specific induction, are currently unknown. Characterization of these downstream modulators of IL-1 beta action complements gene-based approaches and will provide a better understanding of astrocyte responses to injury as well as markers for astrocyte activation in neurodegenerative diseases.

Animals↗
PubMedDate not supplied

A new radiological technique for the forefoot.

Based on a study of 50 subjects seen at the University of Rochester Medical center, a new axial weightbearing radiological technique of the forefoot is described. The technique is simple, inexpensive, and easily reproducible. It has the advantage of not distorting the forefoot, relationships, unlike currently employed techniques. Since it is performed under weightbearing conditions, the results correlate closer to clinical situations. The subjects under this study, which excluded those with neuromuscular or malalignment problems, were found to fall into two categories: the pain-free and callous-free feet group, who have a well defined arch in the forefoot, and the group of subjects with pain and/or callous under the forefoot, who have a depressed arch. There is also a statistical significance between the relative heights of the tibial and fibular sesamoids. A new classification for hallux valgus based on observations of this technique is proposed.

Callosities↗
PubMedDate not supplied

Characterization of dendritic cells generated from peripheral blood of patients with malignant melanoma.

Dendritic cells (DCs) are professional antigen presenting cells. Two x 10(7) peripheral blood mononuclear cells (PBMCs) from each of 6 melanoma patients and 4 normal donors were incubated in 6-well plates. The adherent cells were cultured in GM-CSF (800 U/ml) and IL-4 (1000 U/ml) for 10 days. Anti-CD80, anti-CD86, anti-HLA-DR, anti-HLA-class I monoclonal antibodies and supernatant from two melanoma cell lines were incubated with DCs before responder T cells were added in mixed lymphocyte reaction (MLR). The mean yields of DCs were 3.6 x 10(5) and 9.3 x 10(5) for donor and the melanoma patients respectively. MLR was inhibited by anti-CD80, anti-CD86, anti-HLA-DR, anti-HLA-Class I and supernatant of melanoma cultures. The characteristics of DCs generated from melanoma patients were comparable to those from donors. DC function was inhibited by soluble factors in melanoma cultures. Further studies are warranted to characterize these inhibitory factors.

Antibodies, Monoclonal↗
PubMedDate not supplied

Induction of Th1 response by dendritic cells pulsed with autologous melanoma apoptotic bodies.

BACKGROUND: We hypothesize that dendritic cells (DCs) can process antigens from autologous melanoma apoptotic bodies (MABs) and induce effector T cells in melanoma patients. MATERIALS AND METHODS: Peripheral blood mononuclear cells were obtained from three stage IV melanoma patients and adherent cells were cultured in complete medium (CM) containing GM-CSF (800 U/ml) and IL-4 (1000 U/ml) for 7 days. Autologous MABs from melanoma cells following actinomycin D treatment (0.5 microgram/ml) for 24 hours, were added to 72 hour DC culture. Autologous effector T cells were cultured in CM containing 60 IU/ml of IL-2 and were stimulated by MAB-pulsed DCs three times at a weekly interval. Effector T cells were harvested at the end of third cycle of DC stimulation. RESULTS: Using ELISPOT, IFN-gamma production by effector T cells stimulated by MAB-pulsed DCs was significantly higher than that by T cells without DC stimulation. Microscopy demonstrated phagocytosis of MABs by DCs. CONCLUSIONS: MAB-pulsed DCs are capable of stimulating Th1-directed autologous effector T cells. Pulsing DCs with autologous MABs may be a novel approach in future DC-based immunotherapeutic trials.

Antigens, Neoplasm↗