Histopathologic-molecular correlation in early mycosis fungoides using T-cell receptor gamma gene rearrangement by polymerase chain reaction with laser capture microdissection.

BACKGROUND/PURPOSE: Early mycosis fungoides (MF) is difficult to distinguish from other benign inflammatory dermatoses. We evaluated clonal T-cell receptor (TCR) gamma gene rearrangement by polymerase chain reaction (PCR) as a surrogate to histologic diagnosis in early MF. METHODS: Twenty paraffin-embedded skin biopsies from nine patients diagnosed with MF were included. Two multiplex PCR encompassing various Vgamma and Jgamma regions were used to detect TCRgamma gene rearrangements. Histologic diagnoses were categorized as "diagnostic", "consistent", "suggestive", or "nondiagnostic". We compared TCRgamma PCR results with histologic parameters to determine the differences between PCR-positive and PCR-negative groups. RESULTS: TCRgamma PCR was positive in 53% (8/15) of the patch stage, in 100% (2/2) of the plaque stage, and in 100% (3/3) of the tumor stage. TCRgamma PCR was positive in 50% (4/8) of the specimens in both the diagnostic and consistent of MF groups, 71% (5/7) in the suggestive of MF group. We found that inflammation was more severe in PCR-negative specimens. Papillary dermal fibrosis was common, and differed significantly between PCR-positive and PCR-negative groups (p = 0.01). T-cell monoclonality was detected in one nondiagnostic lesion in a patient with psoriasis and MF. CONCLUSION: TCRgamma PCR allows the diagnosis of MF in patients with lymphocyte-poor lesions, suggestive of MF pathologically. TCRgamma PCR is more likely to be negative with moderate to severe inflammation, particularly with papillary dermal fibrosis. We suggest that the ratio of malignant clonal to reactive T-cells is critical for MF diagnosis.

Biomarkers of exposure, effect, and susceptibility of arsenic-induced health hazards in Taiwan.

Long-term exposure to inorganic arsenic from drinking water has been documented to induce cancers and vascular diseases in a dose-response relationship. A series of molecular environmental epidemiological studies have been carried out to elucidate biomarkers of exposure, effect, and susceptibility for arsenic-related health hazards in Taiwan. Arsenic levels in urine, hair, and nail are biomarkers for short-term (<1 year) internal dose, skin hyperpigmentation and palmoplantar hyperkeratosis are for long-term (many years) internal dose, and percentage of monomethylarsonic acid in total metabolites of inorganic arsenic in urine may be considered as an exposure marker for biologically effective dose. The biomarkers of early biological effects of ingested inorganic arsenic included blood levels of reactive oxidants and anti-oxidant capacity, genetic expression of inflammatory molecules, as well as cytogenetic changes including sister chromatid exchange, micronuclei, and chromosome aberrations of peripheral lymphocytes. Both mutation type and hot spots of p53 gene were significantly different in arsenic-induced and non-arsenic-induced TCCs. The frequency of chromosomal imbalances analyzed by comparative genomic hybridization and the frequency of loss of heterozygosity were significantly higher in arsenic-induced TCC than non-arsenic-induced TCC at specific sites. Biomarkers of susceptibility to arsenic-induced health hazards included genetic polymorphisms of enzymes involved in xenobiotic metabolism, DNA repair, and oxidative stress, as well as serum level of carotenoids. Gene-gene and gene-environment interactions are involved in arsenic-induced health hazards through toxicological mechanisms including genomic instability and oxidative stress.

Type IV hypersensitivity from rubber chemicals: a 15-year experience in Taiwan.

BACKGROUND: Allergic contact dermatitis from rubber chemicals is frequent but has not been reported form Asia. OBJECTIVE: To study the pattern of type IV allergy to rubber chemicals in a Chinese-based population. METHODS: A retrospective study was conducted by reviewing the patch test results of 2,235 (604 men, 1,631 women) patients from January 1986 to December 2000. RESULTS: Ninety-nine patients (4.4%) had one or more positive reactions, 42 (6.9%) men and 57 (3.5%) women. The incidence did not increase throughout the study period. Among thiuram, mercapto, carba and black-rubber mix, thiuram is the most potent sensitizer, mostly for the hand and mercapto mix for the foot. Thiuram allergy is considered occupation related, while mercapto allergy, mostly from rubber slippers, is not typically related to an occupation. A negative correlation between thiuram and carba was found despite the frequent association between these two mixes. A high risk of rubber sensitization was noted in construction, health service, transportation, agriculture and hairdressing workers. A high frequency of concomitant sensitivity to cobalt was found. CONCLUSION: This is the first statistically analyzed study of rubber chemical allergy in Asia, which supports major trends concerning rubber chemical allergy from European studies. However, wearing rubber slippers in Taiwan contributes to the high percentage of foot dermatitis. Carba should still be retained in the European standard series because of the coexistence of thiuram and carba in rubber products. The concomitant sensitization to cobalt in rubber-allergic patients needs further evaluations.

A patch test study of 27 crude drugs commonly used in Chinese topical medicaments.

Chinese topical medicaments (CTMs) are commonly used in Taiwan and in Southeast Asia. However, a systematic evaluation of contact sensitization potential from CTM has not been carried out to our knowledge. This study was undertaken to investigate the incidence of contact sensitivity to the components of CTM in patients with contact dermatitis from CTM. A screening series of 27 crude drugs most commonly used in CTM as well as a modified European standard series was patch tested in 30 patients. The herbs with the most frequent positive reactions were Flos Caryophylli (see text), Radix Angelicae Pubescentis (see text), Cortex Cinnamomi (see text), Cortex Radix Acanthopanacis (see text), Caulis Impatientis (see text), Resina Draconis/Sanguis Draconis (see text), Fructus Cnidii (see text), Radix Gentiana Macrophyllae (see text), and Rhizoma Ligustici Chuanxiong (see text). Concomitant allergy to colophonium was found in most of these positive reactions. Reducing the concentration and simplifying the compositions of these components, as well as replacement with those of low allergenicity in CTM, such as Rhizoma Arisaematis (see text), Herba Lycopodii (see text), Radix Cyathulae Officinalis (see text), Rhizoma Pinelliae (see text), Radix Angelicae Dahuricae (see text), Herba Dendrobii (see text), Secretio Moschus (see text), and Stigmata Croci (see text), may be advocated. A precise labelling of the dosage of each component and the exact chemical compounds in CTM products could further improve the safety and therapeutic effects of CTM in the future.