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Biomedical subjects

T M Lotti

Publications and source records attributed to T M Lotti.

At least 19 recordsLinked to original sources
PubMed2001

Differential expression and secretion of RANTES and MCP-1 in activated peripheral blood mononuclear cell cultures of atopic subjects.

RANTES and MCP-1 represent a link between the activation of monocytes, lymphocytes, basophils, mast cells and eosinophils in inflammatory disorders, such as the late phase allergic reaction. These C-C chemokines also play a role in regulating Th cell cytokine production and leukocyte trafficking. In this study, we determined the expression and secretion of RANTES and MCP-1 from PHA-activated PBMC of healthy and atopic subjects with no symptoms. Levels of RANTES from PHA-activated PBMC of atopic patients were higher, at 18 and 24 h incubations (42+/-5.5 and 48+/-4), compared to controls (20+/-4 and 35+/-4), respectively; while MCP-1 was not (12+/-3 and 17+/-3) compared to controls (10.5+/-3 and 15+/-2), respectively. This effect was also revealed on RANTES mRNA expression, as determined by reverse transcriptase polymerase chain reaction (RT-PCR) analysis. In addition, PHA-activated PBMC of atopic subjects produce more IL-4 (five times more) than healthy subjects, while IFN-gamma did not vary. RANTES, compared to MCP-1, may have more influence on signal transduction pathways, either in physiologic or inflammatory states and may induce profound effects on the regulation of cell activity. The differential production of RANTES and MCP-1 may lead to diverse regulation of the function and development of cells involved in the allergic response. These studies emphasize the importance of chemokine selectivity during inflammation.

Cells, Cultured↗
PubMed1999

UV-B radiation microphototherapy. An elective treatment for segmental vitiligo.

BACKGROUND: Vitiligo is a common disease of unknown cause that produces disfiguring white patches of depigmentation. Previous studies have suggested the effectiveness of UV-B radiation in generalized vitiligo (GV) therapy, but there was no evidence to support the same role for segmental vitiligo (SV). OBJECTIVE: The purpose of this study was to use UV-B radiation exclusively on vitiligo patches of individuals affected by SV to evaluate the effectiveness of this therapy. SUBJECTS AND METHODS: Eight individuals with SV were treated for 6 months with a new device called BIOSKIN that can produce a focused beam of UV-B (microphoto-therapy) on vitiligo patches only. Photographs of the subjects were taken at the beginning of the therapy and once a month thereafter for 6 months. The response to treatment was estimated in two comparable photographs using planimetry. A control group of eight individuals matched for sex and age was treated with placebo, using the same device but not releasing any kind of detectable light. RESULTS: After 6 months of microphototherapy five subjects of the eight studied achieved normal pigmentation on more than 75% of the treated areas. In particular, three of these were totally repigmented. Two individuals achieved 50-75% pigmentation of the treated areas, and only one showed less than 50% repigmentation. In the control group only one patient showed moderate repigmentation (less than 50%). CONCLUSION: UV-B microphototherapy seems highly effective in restoring pigmentation in patients affected by vitiligo. As no side-effects have been observed, this could represent the treatment of choice in the limited (segmental) forms of vitiligo.

Adolescent↗
PubMed1999

Cutaneous necrotizing vasculitis. Relation to systemic disease.

Cutaneous necrotizing vasculitis (CNV) is a complex multisystem disease generally involving the skin and mucous membranes, often accompanied by renal, gastrointestinal, pericardial, neurological, and articular signs and symptoms. CNV may be idiopatical or occur in association with a drug, infection, or underlying disease. CNV has been shown in patients with chronic infections (viral, bacterial, protozoa, helminthic), serum sickness, a variety of collagen vascular diseases (systemic lupus erythematous, Sjögren's syndrome, rheumatoid arthritis, Behçet's disease) hyperglobulinemic states, cryoglobulinemia, bowel bypass syndrome, ulcerative colitis, cystic fibrosis, primary biliary cirrhosis and HIV infection. Association with malignancies is not frequent. Lymphoproliferative disorders (Hodgkin's disease, mycosis fungoides, lymphosarcoma, adult T-cell leukemia, multiple mieloma) and solid tumors (lung cancer, colon carcinoma, renal, prostate, head and neck cancer and breast cancer) may be associated with CNV. Whenever possible, treatment is directed at the elimination of the cause. In other cases after adequate laboratory screening local and systemic therapy are recommended.

Arthritis, Rheumatoid↗
PubMed1998

Treatment pearls from Europe.

Discussing the need for psychological treatment of a dermatological condition with children and families can be a daunting task. Families must be given accurate information about the role of psychological or behavioral factors in the exacerbation or maintenance of their child's condition; however, this information must be presented in a way that families and children do not feel criticized or judged. This article discusses nondrug treatments of skin diseases.

Europe↗
PubMed1997

Propiomelanocortin (POMC) gene expression by normal skin and keloid fibroblasts in culture: modulation by cytokines.

Originally described as a product of the pituitary gland, propiomelanocortin (POMC) has recently been identified in other tissues, such as in human skin, where it may accumulate in response to various stimuli. Thus far, epidermal keratinocytes, as well as melanocytes and macrophages, have been shown to express POMC. This study investigated the expression of POMC mRNA in cultured dermal fibroblasts derived from either normal skin or keloids. Using Northern blot hybridization with a POMC cDNA generated by RT-PCR of mRNA isolated from cardiac muscle, we demonstrated that dermal fibroblasts express POMC, as significant levels of mRNA were detected in unstimulated cells in culture. POMC transcript steady-state levels were strongly reduced by transforming growth factor-beta (TGF-beta), whereas tumor necrosis factor-alpha (TNF-alpha) counteracted the effect of TGF-beta and exerted a stimulatory activity on POMC mRNA levels. Reduction of POMC transcript levels by TGF-beta was also observed in cultured keratinocytes. Clearly detectable levels of POMC mRNA were detected in cultured keloid-derived fibroblasts; however, little, if any, regulation by TGF-beta was observed. These data represent the first demonstration of POMC expression by fibroblasts and down-regulation by TGF-beta. Furthermore, our results indicate altered TGF-beta regulation of POMC gene expression in keloid-derived fibroblasts, suggesting that POMC may play a role in the pathogenesis of keloid formation.

Cells, Cultured↗
PubMed1997

Cyclosporin G inhibits proliferation of A431 cells in a dose- and time-dependent manner comparable to cyclosporin A.

Cyclosporin A (CyA), a fungal metabolite with potent immunosuppressive activity and an antiproliferative effect on epithelial cells, i.e. normal and transformed keratinocytes, is currently proposed in the treatment of psoriasis, where its use is limited mainly by possible nephrotoxicity and/or hepatotoxicity. Numerous analogs of CyA have been produced and studied. The most promising of these is the immunosuppressive analog cyclosporin G (CyG), in which norvaline is substituted for alpha-aminobutyric acid at the 2 position. This would maintain strong immunological activity, with reduced to absent nephrotoxic and hepatotoxic effects. The authors compared the antiproliferative effect of CyG and CyA on the epidermoid carcinoma cell line A431 in vitro, performing the MTT-microculture tetrazolium colorimetric assay based on the ability of viable cells to reduce the MTT compound to a blue formazan product. Subconfluent A431 cells were incubated with CyA or CyG or solvent only, for 24, 48, 72 or 96 h at concentrations of in vivo relevance (0.3, 0.6, 1.25, 2.5, 5, 7.5, 10 micrograms/ml). CyA and CyG showed similar antiproliferative effects, in low-serum-containing media in a dose- and time-dependent manner. After 24 h of incubation, the inhibition of the growth rate was irrelevant. A striking inhibition of the growth rate at the higher concentrations of the drugs (7.5 and 10 micrograms/ml) at 72 and 96 h of incubation was evident. Therefore CyG has been demonstrated to exercise an antiproliferative effect on the A431 cell line. These data suggest possible use for CyG in the treatment of immune-mediated disease, particularly in the treatment of dermatologic diseases characterized by epidermal hyperplasia and/or keratinocyte hyperproliferation.

Cell Division↗
PubMed1987

Polycythaemia rubra vera and water-induced pruritus: blood histamine levels and cutaneous fibrinolytic activity before and after water challenge.

We studied blood histamine activity (HA) and cutaneous fibrinolytic activity (CFA) in a patient with polycythaemia rubra vera (PRV) and water-induced pruritus, before and after water exposure. The results suggest that the water-induced itching in PRV is associated with an increase in HA. In addition, markedly increased levels of CFA were found both before and after water exposure. These findings have been previously reported in patients with aquagenic pruritus (AP) but not in patients with PRV. As the water-induced itching in PRV and AP share many common features, these findings suggest that the pathophysiology of the water-induced pruritus in these two conditions may be similar.

Fibrinolysis↗