title: Study of the vulvar skin in healthy Japanese women: components of the stratum corneum and microbes.
abstract: BACKGROUND
  Although the physiological conditions of vulvar skin in Caucasian populations have been characterized, little is known about these conditions in Japanese women.
  
  
  METHODS
  Skin of the labia, groin, mons pubis, and inner thigh was examined in 40 healthy Japanese women outwith their menstrual period. Skin moisture, skin pH, ceramide content and inflammatory cytokine proteins of the stratum corneum, and bacterial flora were assessed.
  
  
  RESULTS
  Skin moisture was found to be significantly lower in the labia than at the other three sites examined. No differences were found in skin pH. A significant difference in ceramide content was observed between the groin and inner thigh. The ratio of interleukin-1α (IL-1α) and interleukin-1α receptor antagonist (IL-1Ra) was significantly higher in the labia than in the other sites. Numbers of total bacteria, Staphylococcus epidermis, and Lactobacillus spp. were greater in the labia and mons pubis sites compared with the inner thigh. Prevotella spp. were found only in the labia.
  
  
  CONCLUSIONS
  In Japanese women, the skin at the labia is drier and more inflammatory than the skin at the groin, mons pubis, and inner thigh; this cannot be explained by the ceramide content and/or pH of the stratum corneum. Prevotella spp. may perform a key role in the vulvar skin of Japanese women.
authors.affiliation: Departments of Obstetrics and Gynecology, Asahikawa Medical College, Asahikawa, Hokkaido, Japan,Biological Science Laboratories, Kao Corporation, Haga, Tochigi, Japan, andDepartment of Dermatology, Asahikawa Medical College, Asahikawa, Hokkaido, Japan.
authors.forename: Toshinobu
authors.initials: T
authors.lastname: Miyamoto
authors.forename: Syunichi
authors.initials: S
authors.lastname: Akiba
authors.forename: Noriko
authors.initials: N
authors.lastname: Sato
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Fujimura
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Takagi
authors.forename: Takashi
authors.initials: T
authors.lastname: Kitahara
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Takema
authors.forename: Hajime
authors.initials: H
authors.lastname: Iizuka
authors.forename: Kazuo
authors.initials: K
authors.lastname: Sengoku
mesh_terms: D000328:Adult; D044466:Asian People; D001834:Body Water / Q000378:metabolism; D002518:Ceramides / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D004269:DNA, Bacterial / Q000032:analysis; D000078404:Epidermal Cells; D004817:Epidermis / Q000382:microbiology* / Q000502:physiology*; D005260:Female; D006119:Groin; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007778:Lactobacillus / Q000235:genetics / Q000254:growth & development; D018720:Prevotella / Q000235:genetics / Q000254:growth & development; D011425:Propionibacterium acnes / Q000235:genetics / Q000254:growth & development; D012016:Reference Values; D013211:Staphylococcus aureus / Q000235:genetics / Q000254:growth & development; D013212:Staphylococcus epidermidis / Q000235:genetics / Q000254:growth & development; D013848:Thigh; D014844:Vulva / Q000166:cytology / Q000382:microbiology* / Q000502:physiology*; D055815:Young Adult
chemical_list: D002518:Ceramides; D016207:Cytokines; D004269:DNA, Bacterial