[Loneliness and social relations among mothers with infants].

OBJECTIVES: To provide support for child-rearing mothers under circumstances in which they are likely to experience loneliness by studying the status of their social network (contact frequency) and social support as well as the relationship of these variables with loneliness. METHODS: An anonymous questionnaire was distributed to 978 mothers who visited 4 health care centers in Ward A in Tokyo for medical check-ups of their infants aged 3-4 months between August and November 2008. Examined parameters were the revised UCLA Loneliness Scale; basic attributes of mothers and infants; child-rearing environment; presence/absence of a husband (partner), biological parents, friends who were also mothers (''mother friends''), and other friends; presence/absence of an active social network (contact frequency); and social support. Contact frequency was counted and classified according to face-to-face contacts and other contacts. The first multiple regression analysis was performed with loneliness score as the dependent variable and presence/absence of a husband (partner), biological parents, mother friends, and friends as independent variables. The second multiple regression analysis used the loneliness score as a dependent variable to examine relationships among loneliness, social support, and contact frequency with a husband (partner), biological parents, mother friends, and friends. Those with no contact person or supporter or with a missing value were excluded. Therefore, a sub-analysis among mothers with no mother friends was performed. RESULTS: In total, 432 questionnaires were completed and 417 had effective responses (effective response rate, 43.3%). The mean Loneliness Scale score was 34.4±9.0 points. Multiple regression analysis showed that the Loneliness Scale score was higher in those with no mother friend or friends. Mothers with all types of contact persons and supporters had higher loneliness scores if they had longer conversations with husband (partner), less frequent face-to-face contact with mother friends and friends, and less social support from biological parents, mother friends, and friends. However, having supporters and contact persons without mother friends had no apparent relationship with contact frequency, social support, or the loneliness score, but correlated with interpersonal attitudes and mother's awareness. CONCLUSION: To prevent and mitigate the loneliness of mothers engaged in child care, it is important to assess the presence/absence of mother friends and friends; relationships with biological parents, mother friends, and friends; and interpersonal attitudes and awareness of mothers, and then take actions to enhance positive images of maternal roles, provide opportunities for face-to-face contact with mother friends and friends, and obtain social support from biological parents, mother friends, and friends.

The Caenorhabditis elegans ADAMTS family gene adt-1 is necessary for morphogenesis of the male copulatory organs.

Remodeling of the extracellular matrix (ECM) is pivotal for various biological processes, including organ morphology and development. The Caenorhabditis elegans male tail has male-specific copulatory organs, the rays and the fan. Ray morphogenesis, which involves a rapid remodeling of the ECM, is an important model of morphogenesis, although its mechanism is poorly understood. ADAMTS (a disintegrin-like and metalloproteinase with thrombospondin type I motifs) is a novel metalloproteinase family that is thought to be an important regulator for ECM remodeling during development and pathological states. We report here that a new C. elegans ADAMTS family gene, adt-1, plays an important regulatory role in ray morphogenesis. Inactivation of the adt-1 gene resulted in morphological changes in the rays as well as the appearance of abnormal protuberances around the rays. In addition, mating ability was remarkably impaired in adt-1 deletion mutant males. Furthermore, we found that the green fluorescent protein reporter driven by the adt-1 promoter was specifically expressed throughout the rays in the male tail. We hypothesize that ADT-1 controls the ray extension process via remodeling of the ECM in the cuticle.