Localization of E-cadherin Along the Nephron Segments in the Rat Kidney / 대한해부학회지

E-cadherin is a cell adhesion molecule that is expressed abundantly in the kidney. However, the expression pattern in various renal epithelial cells is not well established. The purpose of this study was to determine the cellular localization along the nephron segments in the rat kidney. Kidneys from adult Sprague Dawley rats were fixed in 4% paraformaldehyde and processed for immunohistochemistry. Bumetanide-sensitive Na+/K+/2Cl- cotransporter (BSC1), thiazide-sensitive Na+/Cl- cotransporter (TSC), calbindin D28k, and H+-ATPase were used to identify the thick ascending, distal convoluted stubule, connecting tubule, and collecting duct, respectively. In the rat kidney, Ecadherin was expressed mainly in the basolateral domain of the collecting duct and papillary surface epithelial cells. The expression level of E-cadherin changed gradually in the connecting tubule and became moderate in the distal convoluted tubule, thick ascending limb, and loop of Henle. The S1 and S2 segment of the proximal tubule showed weak immunoreactivity. However, E-cadherin was not expressed in the S3 segment of the proximal tubule in the rat kidney. These results suggest that E-cadherin is a major adhesion molecule in the collecting duct and papillary surface epithelium, and that E-cadherin may play a critical role in maintaining the epithelial polarity of these nephron segments.

Dehydration Increases Osteopontin Expression in Rat Kidney / 대한해부학회지

Osteopontin (OPN), is a secreted phosphoprotein that is expressed in the normal kidney. However, little is known about the role of OPN in the kidney. The purpose of this study was to establish the effect of dehydration on renal OPN expression. Dehydrated rats had free access to normal rat chow, but were deprived of water for 3 days. Kidney tissues were preserved by in vivo perfusion with paraformaldehyde-lysine-periodate (PLP) and processed for immunocytochemistry and in situ hybridization. Serum sodium concentration and urine osmolality were increased in dehydrated rats. Both OPN mRNA and protein were expressed restrictively in the descending thin limb (DTL) and papillary surface epithelium (PSE) in control kidneys. In dehydrated kidneys, there was an increase in OPN mRNA and protein expression in the thick ascending limb (TAL) as well as DTL and PSE. Electron microscopy revealed that OPN immunoreactivity in the DTL and TAL cells was located in the Golgi apparatus and in small cytoplasmic vesicles. These results demonstrate that dehydration status increases the expression of OPN in renal tubules and stimulates the secretion into the urine.

Evaluation of the Anti-inflammatory Effect of a Moisturizer Containing Green-Tea Extracts / 대한피부과학회지

BACKGROUND: For the long-term management of chronic dermatitis such as atopic dermatitis or xerotic eczema, it is important for a clinician to choose a medication that has the least side effects. OBJECTIVE: We planned to evaluate the anti-inflammatory effect of a moisturizer containing green-tea extracts compared with 1% hydrocortisone lotion. METHODS: The anti-inflammatory effects of 1% hydrocortisone lotion and a moisturizer containing green-tea extracts were evaluated in the inflammation of skin induced by ultraviolet B(UVB) irradiation and sodium lauryl sulfate(SLS) irritation. Twice a day application of topical agents for reducing artificially induced local inflammation was done. Mexameter and chromameter were used for the evaluation of erythema. RESULTS: UVB induced erythema continued to increase regardless of applying topical agents. In contrast, SLS-induced erythema slowly decreased with time duration. Furthermore, increasing pattern of erythema was irregular after UVB irradiation. These results suggest that SLS-induced erythema was more reliable for evaluation of anti-inflammatory effects of topical agent. In addition, we found that a moisturizer containing green tea extracts showed nearly the same effect as or even more effective than 1% hydrocortisone lotion. CONCLUSION: A moisturizer containing green tea extracts would be effective for improving dry skin and also for the treatment of atopic dermatitis or xerotic eczema.

A Clinical Study on the Effect of a Cream Containing Ramulus Mori Extract and Tea Tree Oil on Acne Vulgaris and Aerobic Skin Flora / 대한피부과학회지

BACKGROUND: The exact role of aerobic bacteria in the pathogenesis of acne remains controversial but several reports showed that these microorganisms were important in the development of acne lesions and affected the severity of acne by being involved in the inflammatory process. There were several attempts to improve and prevent the acne lesions by using soap or cosmetics containing anti-microbial agents. OBJECTIVE: The purpose of this study was to compare the sebum secretion rates and the number of aerobic bacteria in acne patients after 4 weeks trial of RT cream containing 0.1% tea-tree oil and 0.01% Ramulus mori extract. METHODS: We studied 10 normal controls and 20 acne patients. Sebum secretion was measured by Sebumeter. Clinical efficacy was evaluated by comparing numbers of non-inflammatory and inflammatory lesions. Aerobic bacteria was also cultured from control group and acne patients group before and after RT cream use. RESULTS: Sebum secretion rates in acne patients were higher than those in control, but not statistically significant. Total number of aerobic bacteria in acne patients was higher than that in control (p<0.05). The aerobic bacteria consisted of coagulase negative Staphylococcus, Streptococcus sp., S. aureus in both acne patients and control. After 4 weeks, the number of inflammatory lesions had decreased (p<0.05%). In addition, the number of aerobic bacteria showed the tendency of decrease after RT cream use. CONCLUSION: RT cream consisting of 0.1% tea tree oil and 0.01% Ramulus mori extract was found to be effective and safe for acne patients with especially inflammatory lesions.