The immunofluorescence staining of fungi in chronic dermatophyte infections

Indirect immunofluorescence staining of fungi with specific antisera was demonstrated in biopsy specimens taken from six patients with chronic Trichophyton rubrum infections. However, there was no evidence of immunoglobulin or C₃ deposition in the vicinity of the organisms or elsewhere in the sections. Circulating antibodies to dermatophyte fungi are often not demonstrable in these patients. However, these results suggest that antibody affinity for epithelium docs not account for their absence in patients' serum.     

脱色素技术在恶性黑素瘤HE染色及免疫组化中的应用条件

 目的探索脱色素技术在恶性黑素瘤的HE及免疫组化研究中的最佳适宜条件。方法选取2例恶性黑素瘤的多张组织切片,分别利用不同浓度的高锰酸钾/草酸溶液脱色素处理不同时间,进行HE及免疫组化染色,观察效果及切片脱落情况。结果标本切片脱蜡后使用多聚甲醛进行后固定,以0.25%高锰酸钾溶液及2%草酸溶液进行脱色素处理能得到满意的HE染色;以0.25%高锰酸钾溶液及2%草酸溶液进行脱色素处理,时间分别控制在3 min,在免疫组化染色中获得较好的脱色素结果且同时保持了组织的抗原性。结论0.25%高锰酸钾/2%草酸溶液脱色素法是恶性黑素瘤免疫分子在组织化学表达分析中的最佳合适浓度,脱色时间为3 min。     

免疫荧光技术在皮肤活检组织真菌染色中的应用

目的：评价免疫荧光染色法在皮肤活检组织真菌染色中的应用价值。方法：经组织病理和组织培养确诊的43例皮肤真菌病患者对其石蜡包埋切片分别进行免疫荧光染色、PAS染色。结果：43例皮肤真菌病中PAS染色阳性27例（62.8%）,免疫荧光染色阳性30例（69.7%）,免疫荧光染色法较PAS染色阳性率有所提高,两者差异无统计学意义（P>0.05）。同时两种方法均阴性患者5例,两种方法联合真菌检出阳性率为88.4%。结论：免疫荧光染色是提高皮肤活检组织中真菌检出的重要补充。     

The staining pattern of pigmented spindle cell nevi with S100A6 protein

Background: Spitz nevi typically show strong diffuse staining with S100A6, whereas staining in melanomas is commonly patchy and weak. To our knowledge, S100A6 has not been studied in pigmented spindle cell nevus (PSCN), considered by many to be a variant of Spitz nevus. Methods: Forty‐six archived PSCNs were stained with S100A6 and then categorized by predominant cell size and staining pattern. Results: Eighteen (55%) of the small cell predominant nevi showed patchy staining, eight showed diffuse staining and seven were negative for S100A6. Two predominantly large‐celled ‘PSCNs’ were diffusely positive and had many histopathological attributes of classical Spitz nevi. On review, these two cases were reclassified as Spitz nevi and excluded from the remainder of this study. Of the nevi with mixed cell size, one had no expression of S100A6. In the remaining tumors, the small cells showed patchy staining in eight (80%) and diffuse staining in two (20%). The large cells showed patchy staining in four (40%) and diffuse staining in six (60%). Conclusion: In contrast to the strong diffuse S100A6 staining typical of Spitz nevi, the small spindle cells of PSCN commonly show patchy staining or fail to stain completely. In melanocytic neoplasms composed of small spindle cells, patchy S100A6 staining should not be interpreted as evidence of supporting a diagnosis of melanoma. Puri PK, Elston CA, Tyler WB, Ferringer TC, Elston DM. The staining pattern of pigmented spindle cell nevi with S100A6 protein.     

Chronic pigmented purpura induced by chemical substances

Two cases with chronic pigmented purpura are reported, in one case the skin condition was cleared by stopping the habitual intake of a thiamine preparation and it was provoked by taking the drug. Two out of three commercial thiamine preparations were able to induce skin lesions. In the other case skin lesions were cleared by masking the mouth and nose with sheets of gauze in the workplace, which was filled with dye-dust. As most cases with chronic pigmented purpura are treated non-specifically at present, we suggest that more effort should be focussed on detecting aetiological factors in patients' environments.     

卡泊三醇对黑素细胞黑素合成的影响

目的 探讨卡泊三醇对黑素细胞黑素合成的影响及其作用的可能机制.方法 用噻唑蓝比色法(MTT法)、酶学方法及NaOH法,观察卡泊三醇对黑素细胞增殖及色素合成的作用;RT-PCR和蛋白印迹分别检测卡泊三醇对黑素细胞酪氨酸酶基因转录和蛋白表达水平的影响.结果 10~(-9)～10~(-5) mol/L浓度范围的卡泊三醇对体外培养的黑素细胞增殖的影响与空白对照组比较差异无统计意义(P＞0.05).同样浓度范围下,10~(-9)、10~(-8)mol/L浓度的卡泊三醇能明显增强黑素细胞的酪氨酸酶活性和促进黑素细胞的黑素含量,与空白对照组比较,酪氨酸酶活性可分别升高137%、123%(P＜0.05),黑素含量分别增加40.63%、18.75%(P＜0.05).其中10~(-9) mol/L浓度的卡泊三醇增强黑素细胞的酪氨酸酶活性及促进黑素细胞的黑素含量最明显.与高浓度组、空白对照组比较,10~(-9) mol/L浓度的卡泊三醇使酪氨酸酶蛋白表达增高也最明显.较空白对照组增高270.4%(P＜0.05).结论 卡泊三醇对黑素细胞增殖无影响,可增加黑素细胞酪氨酸酶蛋白表达水平,提高酪氨酸酶活性,从而促进黑素细胞的黑素合成.     

色素痣继发白癜风一例

患者男,8岁.因皮肤白斑1年,于2008年8月2日就诊.患者刚出生时即在右侧颈、肩、胸部出现红斑,1个月后红斑变为黑色,并逐渐出现丘疹、斑块,未予重视.1年前开始在黑色斑块处无明显诱因出现白斑,白斑区内的丘疹、斑块渐脱落.     

Non-invasive visualization of melanin and melanocytes by reflectance-mode confocal microscopy

In vivo visualization of epidermal melanin was performed by reflectance-mode confocal microscopy (RCM). Firstly, we examined the distribution of epidermal melanin in pigmented animals and compared with that of the human skin. Melanocytes in the skin of pigmented animals were found to accumulate a large amount of melanin that can be easily visualized because of its brightness. Their RCM images correlated well with the Fontana-Masson-stained sections for melanin. In contrast, in the human skin, typical dendritic melanocytes were hardly observed even in pigmented lesions, although supranuclear melanin caps were easily visible. These results suggested that human melanocytes rapidly transfer the produced melanin to keratinocytes and do not accumulate it. Secondly, to elucidate the production of melanin by human melanocytes, we evaluated the changes of melanin after a single ultraviolet (UV) exposure. The melanin-accumulating melanocytes were clearly visualized during the skin pigmentation process. The RCM images showed the brightness because of melanin gradually increased from day 4, then dendrite-elongated melanocytes appearing from day 8, and finally melanin caps formed from day 29. In conclusion, RCM successfully evidenced the difference in melanin distribution between the pigmented animals and humans, and the UV-induced pigmentation process in vivo as well.