Progress in the development of piezoelectric biomaterials for tissue remodeling.

Piezoelectric biomaterials have demonstrated significant potential in the past few decades to heal damaged tissue and restore cellular functionalities. Herein, we discuss the role of bioelectricity in tissue remodeling and explore ways to mimic such tissue-like properties in synthetic biomaterials. In the past decade, biomedical engineers have adopted emerging functional biomaterials-based tissue engineering approaches using innovative bioelectronic stimulation protocols based on dynamic stimuli to direct cellular activation, proliferation, and differentiation on engineered biomaterial constructs. The primary focus of this review is to discuss the concepts of piezoelectric energy harvesting, piezoelectric materials, and their application in soft (skin and neural) and hard (dental and bone) tissue regeneration. While discussing the prospective applications as an engineered tissue, an important distinction has been made between piezoceramics, piezopolymers, and their composites. The superiority of piezopolymers over piezoceramics to circumvent issues such as stiffness mismatch, biocompatibility, and biodegradability are highlighted. We aim to provide a comprehensive review of the field and identify opportunities for the future to develop clinically relevant and state-of-the-art biomaterials for personalized and remote health care.

A Hindi version of the Composite Scale of Morningness.

BACKGROUND: Several pen and paper measures of human circadian preference are available in English, but none are available in Hindi, hampering research in circadian behavior among Hindi speaking populations in India and elsewhere. The present study describes a Hindi version of the Composite Scale of Morningness (CSM), a self-reported questionnaire widely used to assess morningness/eveningness (M/E). M/E has been used a proxy for circadian phase in lieu of cumbersome and expensive laboratory studies. METHOD: The thirteen item English version of the CSM was translated into Hindi and independently back translated into English. Inconsistencies between the original and back translated versions were then resolved. Both versions were next administered to bilingual persons at Delhi, India (N=130). After intra-class correlations between the Hindi and the English versions were examined, the Hindi version was administered to community based participants representing different age groups (N=310). RESULTS: There was satisfactory intra-class correlation (ICC) between the total scores for the Hindi and the English versions of the CSM (Cronbach's alpha=0.873), with variation for individual items scores. Total CSM scores in the second sample suggested a significant association with age, consistent with published reports with the English CSM, i.e., morningness tendencies were more likely to be reported by older adults. Significant associations with gender or educational status were not observed. CONCLUSIONS: The Hindi CSM is a brief questionnaire that provides behavioral measures of diurnal preference. It is freely available for research in Hindi speaking populations.

Lichen planus secondary to hepatitis B vaccination.

The association of lichen planus (LP) with liver diseases is now well established. Recent reports suggest that the hepatitis viruses may play a central role in this association. Lichen planus following hepatitis B vaccination is much more unusual. A 19-year-old previously healthy male developed itchy violaceous papules and plaques over the upper extremities eight to ten days after the first injection of hepatitis B vaccine. He developed similar lesions over the upper trunk, neck and lower leg after the second and third injections. A skin biopsy showed a lichenoid tissue reaction. Direct immunofluorescence (DIF) showed multiple colloid bodies and a strong continuous ragged basement membrane zone (BMZ) band with fibrinogen. HbsAg by ELISA and anti-HCV antibodies were negative. The patient was treated with oral steroids and the lesions improved. LP is a pruritic inflammatory dermatosis of unknown origin. An increased prevalence of liver disease in patient with LP has been reported. Since the first case reported by Rebora in 1990, about 15 cases of LP occurring after hepatitis B vaccination have been reported in the literature irrespective of the type of vaccine used.