Rapid diagnosis of Chlamydia trachomatis in male patients by antigen detection in urine samples.

To investigate the diagnostic value of testing urine samples as a rapid method for the detection of chlamydial antigen in males, first-catch urine (FCU) and urethral swab samples were obtained from 668 male patients and examined by an enzyme immunosorbent assay (EIA). Positive results were further analyzed by direct fluorescence antibody tests of the EIA sediment. Antigen detection was possible in 12.7% out of the urethra, in 10.8% out of FCU and in a total of 14.5% of the tested persons. Testing only FCU would have missed chlamydia detection in 25 (25.8%) out of a total of 97 chlamydia-positive males. Testing only genital samples would have missed 12 positive cases (12.4%). The sensitivity and specificity of the EIA test of FCU as compared with urethral swabs were 70.6 and 97.9%, respectively, and differed between urine collected before (sensitivity: 84%; specificity: 98.6%) and after (sensitivity: 65%; specificity: 97.7%; p = 0.1254) urethral sampling. The quantitative evaluation of the EIA results demonstrates that the mean value of the extinction rates was highest in specimens corresponding to a positive result from both sampling sites. This study indicates that the chlamydial detection rate was lower in FCU than in urethral samples. FCU testing may be suitable when urethral sampling is not possible; due to its high rate of unconfirmed borderline extinction, positive results should be confirmed with another chlamydial antigen detection test such as direct immunofluorescence.     

Erythropoietic protoporphyria. The problem of a suitable screening test

Erythropoietic protoporphyria (EPP) is characterized by increased red cell protoporphyrins and is included in the differential diagnosis of children presenting with photosensitivity. In the past 20 years, using the traditional solvent extraction qualitative screening test for blood porphyrins, the diagnosis of EPP had been missed in 9 out of 10 patients but recently, using fluorescence microscopy of erythrocytes, no patients with EPP have been missed. All 14 patients in Northern Ireland known to have EPP were recalled and it was found that fluorescence microscopic determination was positive in all cases. We recommend fluorescence microscopy as the screening test of choice for the detection of increased red cell porphyrins.     

Detection of latent variegate porphyria by fluorescence emission spectroscopy of plasma

Summary The plasma of patients with overt variegate porphyria contains porphyrin with a fluorescence emission maximum at about 626 nm, which is diagnostic for the condition. We have evaluated qualitative fluorescence emission scanning of saline-diluted plasma as a method for the identification of asymptomatic carriers of the gene for variegate porphyria. Plasma from 36 unrelated patients with variegate porphyria. 136 of their asymptomatic first- and second-degree relatives aged 15 years or over, and 322 normal subjects was scanned. An emission maximum between 621 and 627 nm was observed in the 36 patients with variegate porphyria and 54 of their relatives, but not in any normal subject, nor in 56 patients with other types of porphyria. For the detection of asymptomatic adult carriers of the gene for variegate porphyria. fluorescence emission scanning of plasma appears to be 100% specific, with a sensitivity of 86% (95% confidence interval 71–98%). In contrast, the sensitivity of faecal porphyrin analysis as a test for adult gene carriers was 36%. These results suggest that fluorescence emission scanning of plasma should replace faecal porphyrin analysis as the test of first choice for this purpose.     

Double-staining procedure for the fluorescent treponemal antibody absorption (FTA-ABS) test.

The fluorescent treponemal antibody absorption (FTA-ABS) double-staining procedure was reproducible, comparable to the conventional test, and easy to read. We recommend the use of the FTA-ABS double-staining procedure for microscopes with incident illumination, the 100 x/1.30 oil achromatic objective and the 6.3 x ocular to obtain optimal fluorescence, and the KP560 as a barrier filter to exclude rhodamine emission when fluorescein fluorescence is read. With this system, errors related to poor focusing or failure to visualise treponemes on all smears should be eliminated.     

Double-staining procedure for the fluorescent treponemal antibody absorption (FTA-ABS) test.

The fluorescent treponemal antibody absorption (FTA-ABS) double-staining procedure was reproducible, comparable to the conventional test, and easy to read. We recommend the use of the FTA-ABS double-staining procedure for microscopes with incident illumination, the 100 x/1.30 oil achromatic objective and the 6.3 x ocular to obtain optimal fluorescence, and the KP560 as a barrier filter to exclude rhodamine emission when fluorescein fluorescence is read. With this system, errors related to poor focusing or failure to visualise treponemes on all smears should be eliminated.     

In vivo evaluation of sunscreens by spectroscopic methods

Background/aims: The methods available for testing the efficacy of topical sunscreens have improved considerably in recent years. Nevertheless, so far no simple and rapid test has been proposed to measure in vivo transmission spectra of sunscreens in the UVA region.
Methods: Spectral changes that occur after sunscreen application were measured with a fluorescence spectrometer (LS 50B, Perkin Elmer, UK) equipped with a Y-shape quartz guide for in vivo measurements. Three sunscreens with different protection factors in the UVA range were tested. The excitation-emission maps of human collagen, skin and sunscreens were analysed.
Results: As a consequence of the human skin and sunscreen fluorescence map analysis, the optimal spectral regions (both for direct and indirect fluorescence measurements) were detected. In vivo fluorescence and remittance spectroscopy were used to investigate the time dependence in transmission spectra of epidermis with applied sunscreens. We also evaluated the feasibility of in vivo fluorescence measurements for the investigation of the sunscreens'water-resistance.
Conclusion: The procedure is simple, and values obtained can be used to predict UVA protection on the basis of the mathematical algorithms.     

Normal and malignant melanin-containing pigment cells of xiphophorine fish as studied with formaldehyde-induced fluorescence

Embryonic skin and eyes, and melanomas of xiphophorine fish were investigated by fomaldehyde-induced fluorescence in order to test whether the pigment cells in these tissues may be identified by a specific green-yellow fluorescence. Skin of pigmented fish embryos showed no fluorescence in the black pigment cells (melanocytes and melanophores), while skin of albino embryos showed a green-yellow fluorescence in all cells which correspond to the black pigment cells of pigmented embryos. The skin of both pigmented and albino embryos showed a bright orange fluorescence in the red pigment cells (pterinophores). No fluorescence was observed in the retinal pigment epithelium of pigmented embryos, while a green-yellow fluorescence was observed in the pigment epithelium of albino embryos. Neither the melanotic melanomas of pigmented fish nor the amelanotic melanomas of albino fish showed any specific fluorescence.     

Lupus erythematosus and reactive tests for syphilis: update.

Sera of patients with lupus erythematosus can produce false-positive reactions in most serologic tests for syphilis, including the FTA-ABS test. False-positive reactions in the FTA-ABS test can exhibit beaded, borderline or reactive patterns of fluorescence. Beaded fluorescence is commonly associated with anti-DNA antibody and other correlates of lupus activity. Borderline and reactive results are common in both systemic and discoid lupus erythematosus, and are usually not associated with increased clinical activity. TPI and MHA-TP tests appear helpful in detecting false-positive FTA-ABS results.     

Evaluation of the usefulness of immunofluorescence on Tzanck smears in pemphigus as an aid to diagnosis

Direct immunofluorescence was done on smears taken from 38 cases of bullous dermatoses and oral ulceration. 16 of these had pemphigus. All of the pemphigus cases had positive Tzanck smears and fluorescence of individual acantholytic cells and/or intercellular fluorescence of sheets of cells. Other bullous dermatoses showed no acantholysis or fluorescence. Smears from a series of oral lesions (mainly aphthous ulcers) showed intercellular fluorescence of sheets of cells similar to pemphigus. Therefore smear immunofluorescence cannot be reliably used as a diagnostic test in oral pemphigus.     

性病后慢性前列腺炎患者解脲脲原体检测

目的通过荧光定量PCR法定位检测性病后慢性前列腺炎的解脲脲原体,为其诊治提供参考依据。方法共收集性病后慢性前列腺炎43例,按照"四杯法"原理收集尿液和前列腺液及前列腺按摩前的尿道试子标本,分别做前列腺液常规、尿道试子及前列腺液的解脲脲原体荧光定量PCR检测,对比前列腺按摩前、后标本中解脲脲原体拷贝数来进行病原体的定位。结果 43例患者中有2例解脲脲原体阳性,检出率为4.65%。结论性病后慢性前列腺炎中解脲脲原体的检出率较低,但其仍可能参与发病。     

A diagnostically‐challenging case of melanoma ex blue nevus with comprehensive molecular analysis,including the 23‐gene expression signature (myPath melanoma)

Melanoma ex blue nevus (MEBN) is a rare, aggressive, and potentially lethal neoplasm. Distinguishing MEBN from an atypical cellular blue nevus can be very challenging. We report a diagnostically difficult case of MEBN with lymph node metastases, in which single nucleotide polymorphism array and fluorescence in situ hybridization were used to arrive at the correct diagnosis. It was also analyzed by the recently‐introduced proprietary 23‐gene expression signature test. To the best of our knowledge, this is the second reported case of MEBN analyzed by the 23‐gene expression signature, which provided a false‐negative result. More studies are needed to assess the sensitivity and specificity of this test in various melanocytic proliferations.     

Comparison of cardiolipin and treponemal tests in the serodiagnosis of yaws.

Results of the Veneral Disease Research Laboratory (VDRL), rapid plasma reagin (RPR), Treponema pallidum haemagglutination (TPHA), T. pallidum immobilisation (TPI), and fluorescent treponemal antibody absorption (FTA-ABS) tests on sera of 661 children from a region where yaws is hypoendemic are compared. For 107 (16.2%) out of 661 sera the FTA-ABS test was the only one showing reactivity; in these instances the test was weakly reactive (intensity of fluorescence scored as +) and the children had no history and no signs or symptoms of treponemal disease. A solitary, weakly reactive FTA-ABS test result seems to have no clinical significance in these cases. The FTA-ABS test can be used as a confirmatory test for yaws instead of the TPI test, if only the results of sera showing an intensity of fluorescence scored as ++ or more are considered to be positive. There appeared to be no significant differences in the results of the VDRL, RPR, and TPHA tests as screening tests for yaws when the TPI or FTA-ABS tests were used as reference tests.     

Comparison of cardiolipin and treponemal tests in the serodiagnosis of yaws.

Results of the Veneral Disease Research Laboratory (VDRL), rapid plasma reagin (RPR), Treponema pallidum haemagglutination (TPHA), T. pallidum immobilisation (TPI), and fluorescent treponemal antibody absorption (FTA-ABS) tests on sera of 661 children from a region where yaws is hypoendemic are compared. For 107 (16.2%) out of 661 sera the FTA-ABS test was the only one showing reactivity; in these instances the test was weakly reactive (intensity of fluorescence scored as +) and the children had no history and no signs or symptoms of treponemal disease. A solitary, weakly reactive FTA-ABS test result seems to have no clinical significance in these cases. The FTA-ABS test can be used as a confirmatory test for yaws instead of the TPI test, if only the results of sera showing an intensity of fluorescence scored as ++ or more are considered to be positive. There appeared to be no significant differences in the results of the VDRL, RPR, and TPHA tests as screening tests for yaws when the TPI or FTA-ABS tests were used as reference tests.     

Aging and effects of ultraviolet A exposure may be quantified by fluorescence excitation spectroscopy in vivo.

The fluorescence properties of skin chromophores such as tryptophan and collagen cross-links might be useful markers of aging and photoaging. As the fluorescence of pepsin-digestible collagen cross-links was found to increase with aging and decrease with photoaging we investigated the characteristics of this dependence. In vivo fluorescence excitation spectra (emission at 380 nm) of SKH hairless mouse model skin are characterized by two bands centered near 295 nm and 335 nm due, respectively, to epidermal tryptophan moieties and pepsin-digestible collagen cross-links. Several groups of hairless mice were followed over a period of 18 mo to document changes in skin fluorescence with aging. Other groups of animals were exposed to either broad band or narrowband ultraviolet A radiation to determine the effects of ultraviolet A exposure on the fluorescence of the dermal collagen cross-links and to determine an action spectrum for the induced changes. We also found that the intensity of pepsin-digestible collagen cross-links in vivo increases linearly with age and that the fluorescence of epidermal tryptophan decreases linearly with age. We found that the fluorescence of pepsin-digestible collagen cross-links decreases immediately following exposure to ultraviolet A whereas epidermal tryptophan fluorescence increases. Both changes were dose dependent but the increase in tryptophan fluorescence occurred exclusively in young animals (2--6 mo old). We found that the ultraviolet-induced fluorescence decrease of pepsin-digestible collagen cross-links is wavelength specific. The action spectrum for the ultraviolet A effect on the in vivo fluorescence of pepsin-digestible collagen cross-links shows a distinct maximum at 335 nm that corresponds to the maximum in the fluorescence excitation spectrum due to pepsin-digestible collagen cross-links. Our results seem to indicate that in vivo fluorescence of epidermal tryptophan moieties and collagen cross-links in the dermal matrix may serve as markers for skin aging, for photoaging, and for immediate assessment of exposure to ultraviolet A radiation.     

Severe neonatal congenital erythropoietic porphyria

Congenital erythropoietic porphyria is a rare form of porphyria, presenting during the neonatal period or during infancy. Clinical features include photosensitive blistering and severe anemia. Wood's lamp fluorescence of the diaper is a useful screening test. We describe a severely affected neonate with systemic involvement due to a homozygous mutation. Because of ongoing severe hemolytic anemia and severe photosensitivity, bone-marrow transplantation was performed, but the patient ultimately succumbed to chemotherapy-induced lung damage, as well as severe pulmonary hypertension, likely due to his chronic hemolytic anemia.     

Comparison of direct immunofluorescence and cell culture for detecting Chlamydia trachomatis.

Conventional cell culture methods were compared with a direct immunofluorescence test (MicroTrak, Syva UK, Maidenhead, Berkshire) to detect Chlamydia trachomatis in 137 patients (126 women, 11 men) attending a sexually transmitted diseases (STD) clinic. Results obtained by the two tests agreed in 87.6% of cases. Of 34 positive specimens, 17 were detected by culture and fluorescence, 15 by fluorescence only, and two by culture only. The excess of specimens that were negative on culture but positive on fluorescence might be accounted for by delays in culture (up to 18 hours). The MicroTrak test appears to be of value in peripheral hospitals that have to rely on transporting specimens to larger centres for culture.     

Modern cosmetic agents and evidence of their function

Fluorometers modified by quartz light conductors allow the recording of the skin-intrinsic fluorescence. Signals assigned to the aromatic amino acids permit a prognosis concerning the sensitivity of untreated skin to light and the sunscreen factor to be expected after the application of UV filters. We discuss the microdistribution and skin penetration of UV filters and describe the utilization of the image analysis technique both for the count and size determination of fluorescent sebaceous glands and for the quantification of the effects of antiperspirants. Based both on the selective increase of efficacy of deodorant soaps, analytically controlled, and on the differences of the deodorizing effects found in various test groups, we discuss the possibilities of improving deodorants.     

Transdermal drug delivery using disk microneedle rollers in a hairless rat model

Background Transdermal drug delivery systems (TDDSs) represent more reliable and consistent methods of drug dosing than oral administration. However, TDDSs can administer only low molecular weight (MW) drugs and require a power source. Disk microneedle rollers facilitate the passage of low and high MW substances through the direct perforation of the stratum corneum and dermis, without stimulating dermal nerves. Objectives We investigated in vitro whether disk microneedle rollers, developed for the Diskneedle Therapy System (DTS?) in South Korea, can deliver drugs effectively through the skin of hairless rats. Methods The disk microneedle rollers used in the DTS? are metal and consist of several plates bearing microneedles of graded lengths (0.15 mm, 0.25 mm, 0.50 mm). To test in vitro permeation, the skin of a hairless rat was mounted in a Franz diffusion cell system and rolled with a disk roller without microneedles and with rollers fitted with microneedles of each size. Rhodamine B base (80 μl) was applied to the skin for 24 hours, 48 hours, and 72 hours, and dye permeation was detected at 543 nm. Dye binding to the skin was also confirmed using fluorescence microscopy at six hours after the application of rhodamine B. Results Use of the disk microneedle roller increased the skin penetrance of rhodamine B base in hairless rats in accordance with microneedle length, as assessed using a fluorescence penetration test. Conclusions Disk microneedle rollers, as designed for the DTS?, can be used for transdermal drug delivery. Microneedles can be selected according to the length appropriate for each application.     

Disordered keratinocyte differentiation in epidermal tumors and mycosis fungoides

The immunocytochemical method with monoclonal antibodies to human and murine epidermis basal-cell antigen (BCAg) has been used in studies on the disorders in keratinocyte differentiation in epidermal tumors and mycosis fungoides. The fluorescence intensity augmented and BCAg distribution in the cytoplasm grew more diffuse as the degree of the tumor cell differentiation lowered. In mycosis fungoides the BCAg reaction has been positive first in the suprabasal layers; as the disease progressed, the fluorescence has involved the entire epidermis. The BCAg test is a sensitive tool for estimating the epidermal cell maturity in processes associated with impaired differentiation of keratinocytes.     

Autofluorescence of human skin is age-related after correction for skin pigmentation and redness

When measuring the skin fluorescence in vivo, the absorption of chromophores such as melanin and hemoglobin often contribute predominantly to the changes in fluorescence and obscure the information from the fluorophores. We measured in vivo the collagen-linked 375 nm fluorescence (excitation: 330 nm) and 455 nm fluorescence (excitation: 370 nm) from nonexposed buttock skin of healthy volunteers. Skin pigmentation and redness of the same sites were quantified by reflectance of the skin at 555 nm and 660 nm. Multiple regression analysis was used to find the correlation between the fluorescence and skin pigmentation and redness. The fluorescence was corrected for the impact of pigmentation and redness according to the equation found in the regression analyses. The age-related trend of the fluorescence was evaluated. The 375 nm fluorescence showed positive relation to age, whereas the 455 nm fluorescence showed no significant relation to age. The increasing rate of the 375 nm fluorescence (logarithm transformed) was 2% per year, which is comparable with previously published data. The results suggest that the correction of the autofluorescence intensity for skin pigmentation and redness is valid, and the 375 nm skin autofluorescence may be used as a biologic marker of skin aging in vivo.