Occupational issues of irritant contact dermatitis

Occupational irritant contact dermatitis (ICD), a non-immunological cutaneous inflammatory response to a workplace substance, comprises a major portion of occupational dermatoses in industrialized societies, resulting in considerable social and economic implications. The sheer morphological variety of ICD presents a diagnostic and classification challenge; ideotypes identified to date include acute, chronic and cumulative irritant dermatitis, delayed acute irritant dermatitis, irritant reaction, pustular irritant dermatitis, suberythematous irritation, sensory irritation, friction dermatitis and airborne dermatitis. Hand dermatitis is the most frequent manifestation of occupational ICD. This article reviews the various types of ICD, the epidemiological data available to date, risk factors, pathophysiology, diagnosis and management of ICD, emphasizing occupational issues.Paper presented at the Occupational Skin Care Management State-of-the-Art Conference, 1–3 September 2000, Zurich     

Accuracy of ultrasound dating formulae in the late second-trimester in pregnancies conceived with in-vitro fertilization

Purpose: 
To investigate the accuracy of ultrasound dating formulae in the late second trimester of pregnancy. Material and Methods: 
A dataset of 136 singleton pregnancies conceived by artificial reproductive techniques was studied to assess the accuracy of ultrasound dating formulae in the late second trimester, and compared with early second trimester. A total of 21 published ultrasound-dating formulae were tested. Results: 
For most formulae, late second trimester scans yielded results that were marginally less accurate than the early second trimester. The best performance was obtained with dating formulae based on femur length, either alone or combined with the biparietal diameter. These formulae had mean absolute errors of 3-3.5 days. Combining two or more parameters did not result in any substantial gain in accuracy. Conclusions: 
Pregnancy dating by ultrasound in the late second trimester is sufficiently accurate for routine clinical use. Formulae based on femur length appear to be at least as accurate as head measurements.     

Plasma cytokines do not reflect expression of pro- and anti-inflammatory cytokine mRNA at organ level after cardiopulmonary bypass in neonatal pigs

BACKGROUND: Plasma concentrations of inflammatory markers are increased in response to the trauma of cardiac surgery and cardiopulmonary bypass (CPB). It is, however, unknown whether the plasma cytokine levels and cytokine mRNA expression at organ level reflect each other. METHODS: Twenty-six piglets (17-19 days) were allocated to the sham-group (sternotomy only, n = 13) or to the CPB-group (sternotomy, 120 min CPB procedure with 60-min aortic cross-clamp, n = 13). The pigs were observed for 0.5 h or 4 h post-CPB. Plasma levels of IL-1beta, IL-6, IL-8 and IL-10 and mRNA expression of TNF-alpha, IL-1beta, IL-6, IL-8, IL-10 and iNOS in organs were registered with concomitant changes in oxygenation index (OI) and expiratory nitric oxide (NO). RESULTS: In pigs killed 0.5 h post-CPB there was a significant increase in IL-10 mRNA in the lungs and kidneys compared with the sham-group. IL-1beta mRNA was detectable in the kidneys and lungs of the CPB-pigs, while IL-6 mRNA was up regulated only in lungs. In pigs killed 4 h post-CPB a significantly higher IL-6 mRNA was found in heart tissue and a lower IL-10 mRNA was found in lungs of CPB pigs compared with the sham-group. There was a concomitant significant increase in OI and increased plasma IL-8 and IL-10 concentrations in the CPB-pigs compared with the sham-pigs. CONCLUSION: The cytokine mRNA expression pattern was very different for the pigs killed already 0.5 h after the CPB procedure compared with the pigs killed 4 h post-CPB. The plasma cytokine levels poorly reflected mRNA expression of the pro- and anti-inflammatory cytokines.     

Dietary lutein inhibits mouse mammary tumor growth by regulating angiogenesis and apoptosis

Even though we previously reported that dietary lutein can inhibit mammary tumor growth, the mechanism of this action was unknown. Here, we studied the action of dietary lutein through its possible regulation of apoptosis and angiogenesis. Female BALB/c mice were fed a semi-purified diet containing 0 (control), 0.002 or 0.02% lutein (n = 20/treatment) for 2 weeks prior to inoculation with 100,000 -SA mouse mammary tumor cells into the right mammary fat pad. Tumor volume was measured daily until day 50 postinoculation when all mice were killed. Angiogenesis and apoptosis activities in the tumors were measured by immunohistochemistry. Apoptosis and necrosis of blood lymphocytes were quantitated by flow cytometry using Annexin V-FITC and propidium iodide staining. The expression of the p53, Bax and Bcl-2 mRNA was measured by RT-PCR amplification. Lutein was not detectable in the plasma, liver or tumor of unsupplemented mice, but increased in a dose-dependent manner in lutein-supplemented mice. Mice fed lutein had tumors that were 30 to 40% smaller (p < 0.05) on day 50 post-inoculation compared to unsupplemented mice. Final tumor volume was lowest in mice fed 0.002% lutein. Mice fed lutein had higher apoptotic activity in the tumors but lower apoptotic activity in blood lymphocytes as compared to unsupplemented animals. These observations were supported by the observed increase in the expression of the proapoptotic genes, p53 and Bax, together with a decrease in the expression of the antiapoptotic gene, Bcl-2, and consequently an increase in the Bax:Bcl-2 ratio in tumors from lutein-fed mice. Furthermore, lutein-fed mice also had lower (p < 0.05) angiogenic activity in the tumors as compared to unsupplemented mice. The greatest beneficial effect on apoptosis and angiogenesis was observed with mice fed 0.002% lutein. Therefore, dietary lutein, especially at 0.002%, inhibited tumor growth by selectively modulating apoptosis, and by inhibiting angiogenesis.     

Methylation of p16(INK4a) promoters occurs in vivo in histologically normal human mammary epithelia

Cultures of human mammary epithelial cells (HMECs) contain a subpopulation of variant cells with the capacity to propagate beyond an in vitro proliferation barrier. These variant HMECs, which contain hypermethylated and silenced p16(INK4a) (p16) promoters, eventually accumulate multiple chromosomal changes, many of which are similar to those detected in premalignant and malignant lesions of breast cancer. To determine the origin of these variant HMECs in culture, we used Luria-Delbrück fluctuation analysis and found that variant HMECs exist within the population before the proliferation barrier, thereby raising the possibility that variant HMECs exist in vivo before cultivation. To test this hypothesis, we examined mammary tissue from normal women for evidence of p16 promoter hypermethylation. Here we show that epithelial cells with methylation of p16 promoter sequences occur in focal patches of histologically normal mammary tissue of a substantial fraction of healthy, cancer-free women.     

Absence of Neisseria meningitidis W-135 electrophoretic Type 37 during the Hajj, 2002

We document the absence of carriage of Neisseria meningitidis W-135 of the sequence type 11 in returning pilgrims after the Hajj 2002. This finding contrasts with the 15% carriage rate we previously reported in pilgrims returning from the Hajj 2001. The epidemiology of carriage may be changing or may have been controlled by vaccination and a policy of administering antibiotics to pilgrims from countries with a high incidence of meningococcal disease.     

An assessment of orthodontic treatment using occlusal indices.

This retrospective study was carried out to assess the need for orthodontic treatment and the standard of treatment provided by the Government Dental Clinic in Singapore. The materials for this study comprised the pre-treatment and post-treatment study models as well as the clinical notes of 194 patients who were consecutively debanded over a three-month period in 1996. The pre- and post-treatment models were assessed using the Index of Orthodontic Treatment Need (IOTN) and the Peer Assessment Rating (PAR) index. The results indicated that a large proportion (81.4%) of the cases were treated with extractions. The majority of the cases were treated by upper and lower fixed appliances. Treatment was completed, on average, in 21 visits spread over 2.1 years. The result also demonstrated that the majority of the patients had genuine need for treatment for both dental and aesthetic reasons. Eighty-two percent of patients fell into the category of "need" for treatment based on dental health grounds. The mean PAR score reduction was 77%, indicating a high standard of treatment.     

Clinical course of penile fibrosis in intracavernosal prostaglandin E1 injection therapy: a follow-up of 44 patients

A study was undertaken of 44 patients who had developed fibrotic changes in the penis in the course of intracavernosal prostaglandin E1 (PGE1) injection therapy for erectile dysfunction. Of these patients, 75.0% (n=33) were followed up for more than 24 months, and 59.1% (n=26) for more than 36 months. Of the patients, 52.3% (n=23) had clinical improvement of the fibrotic changes without therapeutic intervention and despite most (91.3%) continuing intracavernosal PGE1 injection therapy. These included 25.0% (n=11) no longer having clinically detectable penile fibrosis (PF). The presence of penile curvature or pain did not significantly influence this outcome. The ages of men who showed improvement and the duration of their injection therapy were similar to those who did not improve. It would be prudent to defer therapeutic intervention for PF in the course of intracavernosal PGE1 injection therapy in anticipation of possible spontaneous improvement.     

Absence of inhibition of cutaneous wound healing in mice by oral doxycycline

Temporally controlled expression of genes in transgenic mice has advanced our understanding of many physiological processes. One of the more common modes of acutely altering gene levels involves the doxycycline-regulated "tet-on/tet-off" systems. There has been concern that the administration of doxycycline in itself might compromise many aspects of wound repair. Here we report that oral ad libitum administration of doxycycline (2 mg/ml in drinking water) to mice does not alter dermal or epidermal wound healing. The healing of both full- and partial-thickness skin wounds proceeded similarly regardless of doxycycline administration; in fact, collagen organization and tensile strength development appeared to accelerate in the presence of doxycycline. These data suggest that wound healing studies incorporating transgene expression can utilize tet-on/tet-off regulation of gene expression without interference from doxycycline.