Modified universal new-born hearing screening: Practical approach for developing world (Georgean experience).

AIM: Analysis of newborn hearing screening (NBS) outcomes and proposing a modified strategy for better performance of NBS in developing world. DESIGN: Descriptive (retrospective and prospective) study. METHODS: A total of 8412 newborns/neonates were subjected to risk factor assessment followed by a set of subjective (behavioral audiometry: BoA) and objective (OAE: otoacoustic emissions, ABR: auditory brainstem-evoked responses) hearing-screening in different combinations. DPOAE (primary objective tool) was undertaken in 2565 cases. Predictive value of risk factors on deafness was statistically analysed along with affectivity of objective, subjective and questionnaire-based screening tools. RESULTS: Amongst 8412 babies, 45.5% were 'at risk' (major 36.41%, minor 9.17%). The OAE was abnormal in 299 cases (11.6% of 2565 & 3.5% in 8412). The abnormal OAE rate in prospective cases was 3.5% while in retrospective cases that underwent initial screening with BoA was 41%. A significant correlation was seen with consanguinity, high blood pressure, NICU stay>5 days, low birth weight, neonatal jaundice, delayed birth cry, pre-mature status, birth asphyxia and maternal excessive vomiting, while regression models of OAE outcome (sensitivity 99%, accuracy 89%) revealed highest predictive value for the initial 3 factors. BoA-screening revealed a sensitivity of 72.6%, and negative predictive value of 42.4%. Also a perfect correlation was evident between OAE-ABR, OAE-BoA and ABR-BoA. CONCLUSION: A subjective NBS screening through questionnaire-based-risk-assessment and modified-BoA followed by selective referral for objective assessment is more practical and focussed approach for poor resourced countries that is likely to screen a larger population.

Postnatal ontogeny of Neuromedin S and its receptors NMUR1 and NMUR2 expression in mouse testis.

Neuromedin S (NMS) is a well-known anorexigenic neuropeptide. Despite some reports of the presence of its transcript and precursor protein in testis, the expression and localization of NMS and its receptors during the postnatal development of mammalian testis remains elusive. We investigated the expression patterns and testicular localization of NMS and its receptors NMUR1 and NMUR2, during 5, 10, 20, 30, and 90 days of postnatal development, using real time PCR, immunoblot analysis and immunohistochemistry in mice. NMS and its receptors are present at all age groups at transcript level in mouse testis. At the protein level, NMS and NMUR2 are present in all age groups, whereas NMUR1 is present primarily in 30- and 90-day testis. Immunolocalization study showed that NMS and NMUR2 are expressed in spermatogonia, spermatocytes, Sertoli cells, and Leydig cells, in contrast to NMUR1 which is expressed exclusively in the Leydig cells of 30- and 90-day testis. The results also confirm the intranuclear localization of NMS in spermatogonia and spermatocytes. Although NMS-NMUR2 is expressed in Sertoli cells at all stages of the spermatogenic cycle, they showed a stage-specific expression pattern in spermatogonia and primary spermatocytes. In conclusion, NMS and its receptors NMUR1 and NMUR2 are expressed in the testis and may regulate spermatogenesis, possibly by modulating steroidogenesis and Sertoli cell function in the testis.

Sub-chronic restraint stress exposure in adult rats: An insight into possible inhibitory mechanism on testicular function in relation to germ cell dynamics.

Psychological stress is now widely recognized as one of the major risk factors for male fertility. Its impact on the dynamics of testicular germ cells, however, has yet to be fully investigated. Therefore, we used the rat restraint stress (RS) model as a psychological stressor to assess the impact of psychological stress on testicular germ cell dynamics. Adult male SD rats were exposed to sub-chronic RS for 1.5 and 3 h per day for 30 days. The quality of cauda epididymis spermatozoa was adversely affected by RS exposure, and the frequency of spermatozoa with tail abnormalities was higher than that of spermatozoa with head abnormalities. RS exposure adversely affected testicular daily sperm production by disturbing the meiotic and post meiotic germ cell kinetics in the testis. The histomorphology of the testis was altered by loosening and vacuolization in the seminiferous epithelium, germ cell exfoliation and the presence of giant cells. Seminiferous tubules of stage I-VI and VII-VIII were severely affected in rats exposed to RS for 3 h. By interfering with steroidogenic enzymes, RS exposure disrupts testosterone biosynthesis. The testicular oxidative balance was also disturbed by RS exposure, which disrupted the levels/activities of lipid peroxidation, Nrf-2, superoxide dismutase and catalase. There was also an increase in caspase-3 activity and a decrease in the Bax-Bcl2 ratio. In conclusion, our findings suggest that psychological stressors like RS impair testicular functions in rats by disrupting germ cell dynamics, downregulating testicular androgenesis and increasing oxidative stress and apoptosis.