Severe unconjugated hyperbilirubinemia may cause deafness. In the Netherlands, 25% lower total serum bilirubin (TSB) treatment thresholds were recently implemented for preterm infants.To determine the rate of hearing loss in jaundiced preterms treated at high or at low TSB thresholds.In this retrospective study conducted at two neonatal intensive care units in the Netherlands, we included preterms  treated for unconjugated hyperbilirubinemia at high or low TSB thresholds. Infants with major congenital malformations, syndromes, chromosomal abnormalities or toxoplasmosis, rubella, cytomegalovirus, herpes, syphilis, and human immunodeficiency infections were excluded. We analyzed clinical characteristics and TSB levels during the first ten postnatal days. After two failed automated Auditory Brainstem Response (ABR) tests we used the results of the diagnostic ABR examination to define normal, unilateral, and bilateral hearing loss (>35 dB).There were 479 patients in the high and 144 in the low threshold group. Both groups had similar gestational ages (29.5 weeks) and birth weights (1300 g). Mean and mean peak TSB levels were significantly lower after the implementation of the novel thresholds: 152±43 µmol/L and 212±52 µmol/L versus 131±37 µmol/L and 188±46 µmol/L for the high versus low thresholds, respectively (P<0.001). The incidence of hearing loss was 2.7% (13/479) in the high and 0.7% (1/144) in the low TSB threshold group .Implementation of lower treatment thresholds resulted in reduced mean and peak TSB levels. The incidence of hearing impairment in preterms with a gestational age <32 weeks treated at low TSB thresholds was substantially lower compared to preterms treated at high TSB thresholds. Further research with larger sample sizes and power is needed to determine if this effect is statistically significant. In line with this is the increased likelihood of an abnormal hearing screening test, i.e. an automated auditory brainstem response (AABR), with increasing UCBfree levels in preterm infants of 34 or more weeks of gestation. In 2007, lower treatment thresholds were introduced for the management of unconjugated hyperbilirubinemia in Dutch preterm infants of less than 32 weeks of gestation. In addition, the effect of a variety of demographic and clinical characteristics on hearing impairment was analyzed.According to the Research involving Human Subjects Act (WMO), because this study only includes retrospective research with data, it is not subject to an ethics review and does not need to include informed consent from the subjects, as the data was used anonymously. This study fulfils all the requirements for test subject anonymity and is in accordance with regulations of the review boards of the participating hospitals.Preterm infants of less than 32 weeks of gestation were included when admitted to one of the two participating NICU centers in two time periods: between January 2005 and December 2006, i.e. before introduction of the novel thresholds, and between March 2007 and March 2008. Exclusion criteria consisted of major congenital malformations, clinical syndromes, chromosomal abnormalities or TORCH . These infections were excluded as these conditions are likely to affect hearing status. In addition, infants who died before the automated auditory brainstem response (AABR) was carried out were excluded.2/nm; center 2∶7.4±3.3 µW/cm2/nm; p = 0.11). Eligible infants admitted in 2005 and 2006 to one of the participating NICU centers were included and used as a control group: the high threshold group. In this group, treatment of unconjugated hyperbilirubinemia was applied according to identical guidelines for four (birth weight) categories: <1000 grams, 1000–1500 grams, 1500–2500 grams, and term newborns. In April 2007, a new “consensus based” guideline for preterm infants was implemented in the Netherlands. Treatment thresholds were ∼25% lower in the novel guideline. Total serum bilirubin was tested in the first 10 postnatal days or when clinically indicated. Bilirubin measurements were performed using routine laboratory techniques. In each infant, the mean and mean peak of TSB measurements were calculated and used for analysis.All Dutch NICUs participate in a two-stage AABR neonatal hearing programme. The instruments’ algorithm of the AABR assumes an infant as passing the test when the acquired data obtained at 35 dB fits with 99.96% likelihood a template composed of auditory brainstem responses from normal hearing newborns. Descriptive analyses were performed to determine the incidence of hearing loss and background characteristics in the high and low threshold group. Sensitivity and specificity of mean and mean peak TSB levels were evaluated using receiver-operating characteristics (ROC) curves.No difference was observed in the proportion of infants who were hospitalized ≥ 12 days at intensive care, which is seen as an independent risk indicator for hearing loss. This retrospective cohort study demonstrates that introduction of lower treatment thresholds in preterm infants results in significantly lower mean and mean peak TSB levels. Treatment according to novel treatment thresholds did not result in a significant reduction of hearing impairment, albeit a ∼75% reduction in the incidence of hearing loss. Finally, and in analogy to previous data in term infants, it appeared that TSB level is also a poor predictor of hearing loss in preterm infants.In 2007, the Dutch Society of Pediatrics approved and recommended a novel, “consensus-based” guideline on unconjugated hyperbilirubinemia in preterm infants. Infants treated according to the ∼25% lower thresholds had lower TSB levels: we found a reduction of ∼15% in mean and mean peak TSB levels, supporting an effective implementation of the new guideline.Yet, auditory impairment in preterm infants may also occur at TSB levels below applied treatment thresholds, and - despite the rather low TSB levels- similar TSB levels have contributed to profound neurological impairment including sensoneurinal hearing loss in extreme or very low birth weight infants.The incidence of hearing loss in the control group treated at higher TSB thresholds was in agreement with previous data: in a representative NICU population (10830 neonates with a mean (SD) gestational age 28.5 (1.6) weeks and birth weight of 1039 (256) g) the prevalence of hearing loss was 3.2% (95%-CI 2.6–4.1). Despite these limitations, this is the first study to report on evaluation of a consensus-based national guideline in preterm infants with unconjugated hyperbilirubinemia regarding TSB levels and - unlike other studies - a formal diagnostic ABR (and not a screening ABR) as outcome parameters.We conclude that successful implementation of lower TSB thresholds results in a reduction of mean TSB and mean peak TSB levels, and that larger studies - which preferably also provide data on Bf levels - are needed to establish a statistically significant effect of hyperbilirubinemia on hearing loss in very preterm infants.


While current research priorities include investigations of age-related hearing loss, there are concerns regarding effects on childhood hearing, for example through increased personal headphone use. By utilising historical data, it is possible to assess what factors may have increased hearing problems in children in the past, and this may be used to inform current public health policies to protect children against hearing loss and in turn reduce the long-term burden on individuals and services that may possible evolve. The aim of this study was to investigate which factors in early life significantly impacted on hearing level in childhood using existing data from the Newcastle Thousand Families Study, a 1947 birth cohort.Data on early life factors, including growth, socio-economic status and illness, and hearing at age 14 years were collated for a representative subset of individuals from the cohort (n = 147). Factors were assessed using linear regression analysis to identify associations with hearing thresholds.Males were found to have lower hearing thresholds at 250 Hz, 500 Hz and 1 kHz. Main analyses showed no associations between hearing thresholds and early life growth or socio-economic indicators. An increasing number of ear infections from birth to age 13 years was associated with hearing thresholds at 250Hz (p = 0.04) and 500Hz (p = 0.03), which remained true for females (p = 0.050), but not males (p = 0.213) in sex-specific analysis. Scarlet fever and bronchitis were associated with hearing thresholds at 8 kHz. After adjustment for all significant predictors at each frequency, results remained unchanged.We found no associations between childhood hearing thresholds and early life growth and socio-economic status. Consistent with other studies, we found associations between childhood infections and hearing thresholds. Current public health strategies aimed at reducing childhood infections may also have a beneficial effect upon childhood hearing. Hearing loss is a major public health issue, the magnitude of which is under recognised. The World Health Organisation estimates that there are 275 million people globally with a hearing impairment . Within Many causes and risk factors for impaired hearing status in childhood have been suggested, for example, predisposing genetic traits, infectious or ototoxic intrauterine exposures , perinatal complications (hypoxia), postnatal infections , postnatal trauma  and ototoxic medication use. However, 30-40% of children have hearing loss associated with no known cause or risk factor ,15-17. TBy utilising historical data from the Newcastle Thousand Families Study birth cohort ,24, it iad hoc basis by the study team, which consisted of health visitors and paediatricians [The Newcastle Thousand Families Study began as a prospective study of all children born in May and June 1947 to mothers resident in Newcastle upon Tyne, UK (n = 1142) ,24. The tricians .Information on early life was recorded prospectively for all study members. Birth weights, recorded by the midwife at the time of the child’s birth, were standardised for gestational age and sex . DuratioHearing thresholds were assessed at age 14 years (1961–62) and measured for 147 study members using pure-tone audiometry at eight frequencies between 250 Hz and 8 kHz and recorded on Amplivox audiogram forms. In line with current British Society of Audiology guidelines, hearing thresholds better than 0 dB HL  were given a zero value. An intra individual average (IIA) hearing threshold was calculated as a weighted mean between the ‘best’ and ‘worst’ ear measurement in the ratio 4:1 . Pure toEthical approval for the study was obtained from the appropriate local research ethics committees, the lead of which was the Joint Newcastle Health Authority / University of Newcastle upon Tyne Ethics Committee (ref 94/146), for the analysis of the data and all participants and a parent or legal guardian gave their informed consent at the time of the original data collection.The representativeness of the participants in this study compared to the remainder of the original cohort was assessed using t, Mann–Whitney and chi-squared tests as appropriate for measures taken during early life. Relationships between IIA hearing thresholds at each frequency and pure tone average and explanatory variables were estimated by linear regression, as were potential interactions between explanatory variables. Initially, univariate linear regression models were investigated for each explanatory variable and significant associations deemed by p < 0.05. Multivariable models were then investigated for all significant associations found, with the final models for each frequency only including significant factors. Additional separate analyses were carried out for males and females. All statistical analyses were done using the statistical software package Stata, version 12 .In the 147 study members that participated in the audiometric examinations, there were 83 males and 64 females with complete data  and a short gestation period (31 weeks). Looking at hearing thresholds separately for each ear at each frequency, the individual had significant unilateral hearing impairment and thus gave a high leverage point in regression diagnostics .Further to the associations previously outlined when this study member was included, birth weight  was significantly and negatively associated with IIA hearing thresholds at frequencies 250 Hz, 500 Hz, 1 kHz, 3 kHz and 6 kHz. After adjustment for other significant associations standardised birth weight remained negatively associated with hearing thresholds at frequencies 250 Hz, 500 Hz, 1 kHz and 3 kHz, but again was limited to females. Gestational age at birth was associated with hearing thresholds at all frequencies except for 8 kHz. After adjustment for other significant predictors these associations remained, but in sex-specific analyses were limited to females.Within this birth cohort, males at age 14 years were seen to have lower hearing thresholds than females. Our analyses  showed no associations between standardised birth weight and hearing thresholds or between gestational age and hearing thresholds. Further to this, no associations between socio-economic factors and hearing thresholds at age 14 years were found. A significant association between the number of ear infections (age 0–13 years) and hearing thresholds at age 14 years was found; with a greater number of infections associated with higher thresholds. An association was also seen between hearing thresholds and having been infected with scarlet fever and, or, bronchitis. No association was seen between hearing thresholds and having had rubella, measles, mumps, tuberculosis and, or, pneumonia. We also investigated associations between pure tone average data for the cohort, early-life factors and infections, finding no significant associations other than a sex difference.If a female who had outlying measurements for her IIA hearing thresholds and a relatively short gestation was included in the analyses further associations were seen between birth weight, standardised birth weight and gestation. The decision to exclude this individual was based upon their outlying IIA hearing threshold data and their high leverage in regression diagnostics, since leverage data points can make beta co-efficient estimations inaccurate. Thus, any conclusions drawn about explanatory variables related to hearing thresholds with inclusion of this data could be misleading and should be viewed tentatively. However, this does not necessarily mean that associations found when this individual is included in analyses are invalid.The main strengths of this study are those of the dataset analysed, in particular the longitudinal nature, breadth of and completeness of data collated within the Newcastle Thousand Families study. Data were prospectively collected on early life experience, including gestational age, parity and socio-economic circumstances at birth, as well as other indicators of early life socio-economic, familial and nutritional status. Hearing thresholds at age 14 years throughout low to high frequencies were also assessed prospectively. This meant potential biases that may be introduced when using recalled information were eliminated. This study may also uniquely have assessed risk factors for non-noise induced hearing loss, as during the era in which these individuals were aged 0 to 14 years, it is likely that exposure to hazardous levels of noise would have been lower than for children today due to the inexistence of personal media devices and, probably for this age and era, much less exposure to heavily amplified music. It is possible that, as children, these individuals would have been exposed to other forms of noise, but as they were all below the legal school leaving age in the UK, it is likely that this assessment took place before any industrial-based exposures would have had an impact. As the study included 8 dependent variables and 19 independent variables, this means that 152 univariate associations were tested. Given the large number of tests done, we cannot rule out that some of the reported associations were significant by chance. For each dependent variable, there was only one final model.As far as we are aware this is the only cohort study to look at associations with childhood hearing thresholds of all magnitudes across both high and low frequencies within a UK setting. A study based on The National Child Development Study (NCDS), a cohort born in 1958, reported hearing thresholds at 7, 11 and 16 years ,22, but Consistent with findings from Hall et al’s UK cohort study , we founThe differences seen between our study and others on hearing thresholds may be real or perhaps reflect a lack of power within our study to detect small effects. While significant associations were seen for the non-grouped form of number of ear infections, none were seen using the categorical term. This is likely to reflect the information and variability lost when collapsing the number of infections into just three groups. In addition to the small sample size, this is likely to reflect the difficulties introduced by an average measure when different associations were seen at different frequencies. Younger cohorts living in more economically developed nations now have much lower incidence rates of many of the diseases included in this study than this cohort would have had. This is in part due to vaccinations, but also due to improved living conditions. Hence, it is unclear how the results of the current study, obtained from an historical, pre-vaccinated cohort living in very different conditions to today’s children, would transfer to modern populations. Nevertheless, rates of scarlet fever within the UK are currently at the highest rates for nearly 20 years , and disCurrent public health strategies aimed at reducing childhood infections further may have a beneficial effect upon childhood hearing. Further research is needed in this area to clarify the links between infections, socio-economic status, childhood exposure to recreational noise and fetal growth on later hearing status.The authors declare that they have no competing interests.MP and AR acquired the data and conceived the idea for this study. RN, KM and FP analysed the data under supervision of MP and AR. FP drafted the paper with critical revisions and final approval from all authors. All authors read and approved the final manuscript.The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1472-6815/13/9/prepub


Although the etiology of varicose veins remains unknown, recent studies have focused on endothelial cell integrity and function because the endothelium regulates vessel tone and synthesizes many pro- and anti-inflammatory factors. The aim of this study was to investigate the evidence involving the endothelium in the development of varicose vein disease. In addition, tissue remodeling was investigated in varicose veins to determine the expression of different types of collagen. Tissue specimens of superficial varicose veins and control saphenous vein were used for immunohistochemical and transmission electron microscope (TEM). α-smooth muscle actin, and collagen I, III, IV antibodies were applied for immunohistochemical investigation. Findings of this study showed alterations of the intima, such as focal intimal discontinuity and denudation of endothelium; and the media, such as irregular arrangements of smooth muscle cells and collagen fibres in varicose veins. Our findings showed some changes in terms of distribution of types I, III and IV collagen in the intima and media of varicose vein walls compared with controls. These alterations to the media suggest that the pathological abnormality in varicose veins may be due to the loss of muscle tone as a result of the breakup of its regular structure by the collagen fibres. These findings only described some changes in terms of distribution of these types of collagen in the intima and media of varicose vein walls which may result in venous wall dysfunction in varicosis. Varicose vein disease is a disorder of the lower extremities  characteAlthough endothelial cells are able to synthesize basement membrane and interstitial collagen, the principal source of collagen in the vessel wall is the smooth muscle cell. Alteration of smooth muscle cells behaviour from quiescent or “contractile state” typical of the normal vessel phenotype to a proliferative or “synthetic state” characteristic of the atherosclerotic phenotype increases collagen synthesis .vasa vasorum and nerve fibres in the adventitia  undergoing long saphenous vein harvesting for coronary artery bypass grafting at the Shahid Modarress Hospital in Tehran, Iran. All patients had some degree of high blood pressure, atherosclerosis and heart disease. Tissue specimens were obtained from 20 patients  with superficial varicose veins, undergoing surgery for varicose veins at the Wharfedale General Hospital at Otley. The diagnosis of primary varicose veins was made by the referring surgeon and confirmed by venous duplex scanning. These were defined as clinically evident varicose veins, CEAP grade 3 or above. Appropriate ethical approval and informed consent was obtained in all cases.ImmunohistologyControl and patient saphenous vein was snapped frozen in OCT  then 5μm frozen sections were cut using a Cryostat (LEICA CM 1800), placed onto Poly-L-Lysine (0.1%) (Sigma-Aldrich Company Ltd. UK.) coated slides, and used for immunohistochemical analysis. Immunostaining was carried out as described previously ,23. The Electron Microscopy For electron microscopy the tissue was washed with PBS and then cut into blocks no bigger than 1mm3 . Preparation of sections was carried out as describedpreviously ,25. The ImmunohistologyExpression of α -Smooth Muscle Actinα-SMA antibodies were used to demonstrate the presence of smooth muscle cells. All of the smooth muscle layers in the veins reacted strongly with α -SMA. The individual smooth muscle bundles were completely separated and located close to the intima in all of the control saphenous vein specimens. Longitudinal (LM) and circular (CM) smooth muscle bundles in the media were recognisable in thirteen (65%) varicose vein specimens. The LM and CM bundles were not distinguished in seven (35%) varicose veins specimens as separate bundles when compared to other varicose and control saphenous vein specimens .The inneTypes I, III and IV collagenIntensive staining of type I collagen was seen in the subendothelial region of 9 of 20 specimens (45%) of varicose vein. Less intensive staining was seen in the rest of vein wall in the same specimens . A furthDistribution of type III collagen in 3 (15%) varicose vein specimens showed weak staining in the media. In all control saphenous vein, the immunostaining of type III collagen was scattered between smooth muscle cells beneath the endothelial cell layer . Immunolocalisation of type III collagen was found in the subendothelial layer of all varicose vein specimens (100%) and in the media and the adventitia of 16 specimens (85%)  Table1)Table1).Type IV collagen staining of control  and variIn all the specimens of control and varicose vein (100%), strong staining of type IV collagen was detected in the intimal, medial and adventitial layers. Excepting the intimal layer which stained strongly with type IV collagen, the appearance of type IV collagen staining in the media and the adventitia of all control saphenous vein specimens was the same as α-SMA staining and demonstrates intact basement membrane around the smooth muscle cells in those areas .Electron microscopyTransmission electron microscopical investigation identified changes in the varicose vein structure compared with control samples. Ultrastructural examination of 3 varicose vein specimens (15%) showed that elastic fibres were as thick as the internal elastic lamina in some areas, in which contrasts with the rest of varicose vein specimens which no internal elastic lamina was detected. In 17 out of 20 (85%) specimens of control saphenous vein  an inter Ultrastructural examination of the tunica media in the varicose vein showed disorganization of smooth muscle cells close to the intima in 17 (85%) specimens when compared with normal organized arrangement of smooth muscle cells in 18 (90%) of control saphenous vein specimens. Smooth muscle cells in the control saphenous vein specimens were more closely arranged and showed their regular sheet-like organisation when compared with those varicose vein tissues which showed wide separation of the smooth muscle cells by an increased amount of extracellular matrix and variable bands of collagen fibres .The smooth muscle cells close to the adventitia in 15(75%) varicose vein specimens were not arranged closely and regularly when compared with organisation of smooth muscle cells in the same area in 18 (90%) of control saphenous vein specimens. In two specimens of control saphenous vein (10%) disarrangement of smooth muscle cells close to the adventitia was identified. An accumulation of collagen fibres filled the space between the smooth muscle cells in the media of 16 (80%) varicose vein specimens. These fibres were arranged more irregularly when compared with regularly organized collagen fibres in control saphenous veins . In somevasa vasorum and collagen fibres. The smooth muscle cells in the adventitia of 19 (95%) varicose vein specimens were separated by collagen fibres not as closely packed as in the control saphenous vein. There were no significant differences between the varicose vein and the control specimens with respect to the pattern of endothelial cells and smooth muscle cells in vasa vasorum.The adventitia in varicose and control saphenous veins consists of smooth muscle cells, One of the strongest arguments for varicose vein wall changes is based on the changes observed in the composition of the connective tissue of the varicose vein wall. In the present study, immunostaining showed that bundles of longitudinal and circular smooth muscle cells in all of the control saphenous veins were completely separated, whereas, only in 65% of varicose vein specimens could smooth muscle bundles be recognised in the media. Moreover, among the specimens of varicose veins which show separated longitudinal and circular bundles of smooth muscle cells in the media, the thickness of each bundle appeared to be varied in different parts of the vein wall. This finding confirmed the observation of Stücker et al. that the layer size of circularmuscle in the media was reduced in parts of varicose veins  but the staining was weak. Our findings which showed strong staining of type III collagen in both the subendothelial and medial layers compared with type I collagen in varicose veins, do not quantify the level of collagens. Other investigators have quantified the overproduction of type I collagen and decreased production of type III collagen in varicose veins compared with control saphenous veins ,21 35-3-335-37. Our results using both light and electron microscopy studies confirm significant alterations of morphology of the media of varicose veins when compared with control saphenous veins. In addition, collagen fibres were distributed more irregularly in most varicose vein specimens when compared with the regularly organized collagen fibres in the majority of control saphenous veins. These alterations in the distribution of pattern of type collagen to the media suggest that the pathological abnormality in varicose veins may be due to the loss of muscle tone as result of the breakup of its regular structure by the collagen fibres. These findings only described some changes in terms of distribution of these types of collagen in the intima and media of varicose vein walls compared with controls which may result in venous wall dysfunction in varicosis.


Age-related hearing impairment (ARHI) affects 25–40% of individuals over the age of 65. Despite the high prevalence of this complex trait, ARHI is still poorly understood. We hypothesized that variance in hearing ability with age is largely determined by genetic factors. We collected audiologic data on females of Northern European ancestry and compared different audiogram representations. A web-based speech-to-noise ratio (SNR) hearing test was compared with pure-tone thresholds to see if we could determine accurately hearing ability on people at home and the genetic contribution to each trait compared. Volunteers were recruited from the TwinsUK cohort. Hearing ability was determined using pure-tone audiometry and a web-based hearing test. Different audiogram presentations were compared for age-correlation and reflection of audiogram shape. Using structural equation modelling based on the classical twin model the heritability of ARHI, as measured by the different phenotypes, was estimated and shared variance between the web-based SNR test and pure-tone audiometry determined using bivariate modelling. Pure-tone audiometric data was collected on 1033 older females (age: 41–86). 1970 volunteers  participated in the SNR. In the comparison between different ARHI phenotypes the difference between the first two principle components (PC1–PC2) best represented ARHI. The SNR test showed a sensitivity and specificity of 89% and 80%, respectively, in comparison with pure-tone audiogram data. Univariate heritability estimates ranged from 0.70 (95% CI: 0.63–0.76) for (PC1–PC2) to 0.56 (95% CI: 0.48–0.63) for PC2. The genetic correlation of PC1–PC2 and SNR was −0.67 showing that the 2 traits share variances attributed to additive genetic factors. Hearing ability showed considerable heritability in our sample. We have shown that the SNR test provides a useful surrogate marker of hearing. This will enable a much larger sample to be collected at a fraction of the cost, facilitating future genetic association studies. ARHI, also referred to as presbycusis, is a complex age-related disorder affecting 25–40% of all individuals older than 65 years. Hearing loss can cause severe communication disability, leading to social isolation −17) Complex traits may be attributed to a combination of environmental and genetic factors. Several environmental factors have been implicated in the development of ARHI. Significant environmental risk factors include noise exposure  NAT2*6A polymorphism  GSTT1 and GSTM1  GRHL2 (p = 8.38×10−5) NAT2*6A could be replicated in an independent European cohort (p = 0.013) Several linkage, candidate gene and genome-wide association (GWA) studies have attempted to elucidate the genetic background of ARHI. Linkage studies revealed 6 loci linked to presbycusis on Chromosomes 11, 10, 14 and 18 (LOD>1.5) GRM7 gene (p = 9×10−5) in a European mixed gender case-control cohort  IQGAP2 gene (p = 3.55×10−7) in the Finnish Saami  Two GWA studies have been conducted for ARHI, showing suggested associations with polymorphisms in the This study aimed to determine genetic causal factors of differences in hearing ability with age in middle aged female twins of Northern European ancestry using two different objective measures of hearing ability: the standard pure-tone audiogram administered in controlled conditions to twins visiting the department and a web-based speech-to-noise ratio test which twins were invited by email, to perform online from home www.twins.ac.uk). This twin registry comprises mainly female, adult volunteer twins recruited previously via UK media campaigns Twin subjects were recruited from the TwinsUK registry at St. Thomas’ Hospital, King’s College London (There is no gold standard method for defining ARHI and different groups have used pure tone averages (PTAs) for different frequency ranges, standardized Z-scores The PTA and BEHL are averages calculated from pure-tone thresholds of all frequencies or 0.5 kHz–4.0 kHz for the better ear, respectively. Principal component analysis is a statistical procedure based on correlations between variables. Underlying correlations between the pure-tone thresholds are determined and summarised in new variables, referred to as PCs. In case of pure-tone audiogram data, three PCs have been reported that account for size and shape of the audiogram, respectively Two criteria were applied to define a good phenotypic representation for hearing loss with age: high correlation with age and the characteristic downslope of the pure-tone audiogram. As PC2 has been shown previously to capture the slope of the audiogram The SNR test measures the ability to understand words against increasing background noise. Difficulty in following a conversation in a noisy environment is one of the main symptoms of hearing loss due to advanced age. The test used in this study was originally developed for use on a telephone To determine the reproducibility of the SNR test we selected 17 individuals (age range 20–83) to perform the test twice under similar conditions . We compared the test results using a Bland-Altman comparison The results of the web based SNR test were validated against the pure-tone audiogram data. Subjects for the validation experiment (n = 351) were selected from the TwinsUK cohort if they participated both in the pure-tone audiogram and the SNR. The validation experiment included only female participants. The SNR validation cohort showed a similar age and hearing ability distribution as the pure-tone audiogram cohort . The correlation of the SNR test results were determined for different pure-tone audiogram presentations . Sensitivity and specificity of the SNR test was compared to a PTA>40 dB and a (PC1–PC2) score of 3.4 as thresholds for good hearing ability. Receiver operating curves were calculated. To determine shared causal factors between both hearing tests, bivariate structural equation modelling based on a correlated factors model was performed for PTA and SNR as well as (PC1–PC2) and SNR. For the bivariate analysis, SNR data was normalized using a cubic transformation. Heritability estimates for hearing ability with age as a quantitative trait were calculated using structural equation modelling in Mx Pure-tone audiograms and hearing questionnaire data were collected from 1033 female participants, including 264 DZ and 232 MZ pairs and 41 singletons. The mean age was 62.23 years (± 8.12 years of standard deviation), range 41–86 years. There was no significant age-difference (p = 0.97) for MZs, DZs and singletons . PCA was2 = 0.26) and thus resulted in the lowest rank  and BEHL did not differ significantly between MZs, DZs and singletons . PC1 values increased with raised hearing thresholds whereas PC2 values decreased with increasing downslope in the audiogram . We concluded that a low PC1–PC2 value (i.e. low PC1-high PC2) would reflect good hearing ability, whereas a high PC1–PC2 value (i.e. high PC1-low PC2) would represent hearing loss with age. The highest correlation with age was determined for the combined variable of PC1–PC2 (r = 0.61) . This coest rank .1970 subjects responded to the web-based SNR test within the first 3 months. This first sample set included 348 MZ and 179 DZ twin pairs, as well as 916 unpaired twins. SNR scores did not differ significantly between both sexes . SNR scores ranged from 6 dB −13.5 dB .The results of the SNR test were reproducible with a mean difference between repeat measurements of −0.43 (95% CI: (−0.956) – 0.095). Pitman’s test for difference in variance showed no significant difference (p = 0.879).The highest correlation with the SNR was found with PTA (r = 0.62). We decided to validate the SNR test results against PTA and PC1–PC2, which gave the best ranking in the comparison of pure-tone audiogram phenotypes. Moderate hearing impairment is defined as a PTA> 40 dB Tests measuring the same trait might also reflect a high proportion of shared genetic factors. We investigated bivariate heritability between the two best pure-tone audiometry measures ((PC1–PC2) and PTA) and SNR results. For all bivariate analyses, the AE model gave the better model fit compared to the saturated ACE model . Correla2 statistic and the number of degrees of freedom. For each phenotype the saturated ACE model as well as nested models with better model fits are reported , common environmental and unique environmental factors for different ARHI phenotype presentations. There was a high correlation with age, so age-adjusted residuals were calculated. Results of the univariate heritability study are given in reported . The AE reported .For this study, we collected pure-tone audiogram data and SNR data of 1033 and 1970 mainly female participants, respectively. (PC1–PC2) was suggested as new phenotype definition for hearing ability with age, which showed a high correlation with age and best captured high frequency hearing loss. We have shown that the SNR is a valid tool when compared with the standard test and will allow us to increase our sample size for future GWAs on hearing ability with age as a quantitative trait. The moderate univariate heritability determined for pure-tone audiogram phenotypes suggests causal genetic factors involved in the etiology of hearing ability with age.The TwinsUK cohort has been shown to be widely representative of the general singleton North European population For the pure-tone audiogram representations, the values of the better ear were chosen for analysis, as it is considered to be less representative of environmental factors affecting hearing ability. Exposure to such factors would not represent natural age-related hearing and therefore bias the search for an ageing phenotype. We decided not to adjust for noise exposure in this study, due to minimal self reported exposure in the presented cohort . In addition, noise exposure was not significantly associated with hearing ability (p = 0.92) in our cohort.Several phenotypes have been used to represent hearing ability with age in previous studies, however, no gold standard could be decided on. Moderate hearing impairment (PTA>40 dB), as defined by the WHO In this study, we validated a measure of hearing ability obtained via the web, the SNR test. This test has previously been validated for telephone usage These sensitivity and specificity values might be too low for a diagnostic test, but appropriate for a screening test, as used here. Word recognition and hearing sensitivity at different frequencies represent different aspects of ARHI and might be explained by different causal factors. To reduce the effect of cognitive ability on word recognition digit combinations were used as speech material rather than complete sentences. We hypothesized that variances in both measurements could be explained by shared causal genetic factors and our bivariate heritability results underline this notion. Genetic correlations between pure-tone audiogram measurements (PTA and (PC1-PC2)) and SNR determined in the bivariate analyses ranged from r =  −0.61 to r = −0.67. According to the sensitivity and specificity as well as the high bivariate heritability correlations determined, we conclude that the SNR represents a satisfactory surrogate to the pure-tone audiogram and that both tests could serve as complements to each other.The heritability estimates from the univariate analysis ranged from 70% (95% CI: 0.64–0.76) for (PC1–PC2) to 57% (95% CI: 0.49–0.63) for PC2. This is comparable to a heritability of 75% for pure-tone thresholds reported for female Finnish twins The moderate to high heritability estimates confirm the involvement of genetic factors in the etiology of ARHI as well as the reliability of the phenotype measure.We accept that there were limitations to our data collection. Conductive hearing loss, commonly diagnosed as an air-bone gap of >20 dB, could not be fully excluded, due to a lack of bone conduction measurements. However, auditory diseases leading to conductive hearing loss  were covered in the questionnaire and subjects were excluded upon these pathologies. In addition, hearing loss generally refers to a longitudinal process, whereas the data we presented here was cross-sectional. The percentage of subjects with moderate hearing loss as defined by the WHO (PTA>40 dB) File S1Copy of hearing questionnaire. The Hearing questionnaire was developed to test for self reported hearing loss and exposure to environmental risk factors for hearing ability.(DOCX)Click here for additional data file.Table S1Results of bivariate variance modelling for PTA & SNR and PC1–PC2 & SNR. Results of bivariate structural equation modelling are given for unadjusted and age-adjusted pure-tone audiogram phenotypes. The nested AE models were compared to the saturated ACE model. Model fit is given as minus 2 log likelihood (−2 log L), degrees of freedom (df) and difference in −2 log L and df between the nested and saturated model  are shown. Estimated variances explained by the specific causal factors  are given with 95% confidence intervals for each model. For each model, univariate estimates for each phenotype separately and the correlation (r(a2), r(e2) and r(c2)) between these estimates are reported.(DOCX)Click here for additional data file.


Rhinopithecus roxellana) from the Qinling Mountains of central China and found that about 29.7% of grooming bouts were reciprocated. However, the durations of grooming bouts offered and returned was asymmetrical within dyads. In bisexual dyads, more grooming was initiated by females than males, which became more pronounced as the number of females per one-male unit increased. The rate of copulation per day for each female was positively correlated with the total duration of grooming time females invested in males.. Females without an infant (non-mothers) directed more grooming towards females with an infant (mothers) and were significantly more likely to be non-reciprocated. There was a significant negative relationship between non-mother and mother grooming duration and the rate of infants per female in each one-male unit. High-ranking females also received more grooming from low-ranking females than vice versa. The rate of food-related aggressive interactions was per day for low-ranking females was negatively correlated with the duration of grooming that low-ranking females gave to high-ranking females. Our results showed that grooming reciprocation in R. roxellana was discrepancy. This investment-reciprocity rate could be explained by the exchange of other social services in lieu of grooming.Social grooming is a common form of affiliative behavior in primates. Biological market theory suggests that grooming can be traded either for grooming or other social commodities and services. When no other services are exchanged, grooming is predicted to be approximately reciprocated within a dyad. In contrast, the amount of reciprocal grooming should decrease as other offered services increase. We studied grooming patterns between polygamous male and female in golden snub-nosed monkeys ( A strict seasonal breeder R. roxellana lives in a multi-level social organization R. roxellana, a polygynous colobine species, the basic social and reproductive unit is the one-male unit, which consists of a single resident male, 4.19±1.69 adult females, 0.59±0.72 subadult individuals, 3.94±2.36 juveniles, and1.74±1.38 infants . The mating season ranges from September to December with births occurring from March to May R. roxellana clearly differs from the other two species in terms of individual social relationships and dynamics R. roxellana females appear to disperse across one-male units. Sometime they even disperse to different troops. Dispersion among females does not occur frequently. The composition of harem females in each one-male unit is stable for a period of time. However, when the single resident male has been in the one-male unit for more than five years or the number of females in the one-male unit becomes large, the frequency of female dispersion will increase. In addition, some females will disperse together from one one-male unit to another one-male unit The golden snub-nosed monkey . All research reported here adhered to the regulatory requirements of Zhouzhi National Reserve, China, where the study took place, and to the American Society of Primatologists principles for the ethical treatment of primates.2 of temperate forest. Vegetation types diversify with altitude, consisting of deciduous broadleaf forest from 1,400–2,200 m, coniferous and deciduous broadleaf mixed forest over 2,200 m and coniferous forest above 2,600 m, and the area has a semi-humid montane climate The study was conducted in the Yuhuangmiao region of Zhouzhi National Nature Reserve (ZNNR), which is located on the northern slope of the Qinling Mountains, Shaanxi Province, China. . This region consists of 52,931 kmThere are two troops of golden snub-nosed monkey inhabiting the study area, the East Ridge troop (ERT) and the West Ridge troop (WRT), which are separated by the Nancha River. Based on over ten years continuous observation, the WRT was chosen as the troop for this study. The troop is characterized by a multi-level social structure consisting of an all-male band and one or two bands including one-male units. Details of the study troop have been reported previously The social composition of the focal one-male units in the WRT during our observation period are presented in Individual identification was based upon prominent physical characteristics, such as facial contours, body size, pelage coloration, crown hair pattern, scars, evidence of previous injury , and the shape of granulomatous flanges on both sides of the upper lip Adult males with conspicuous large bodies covered with extraordinarily long, brilliantly golden guard hairs across the entire dorsum. Body areas, such as the cape area, the dorsum, crown to nape, and arms were deep brown. The granulomatous flanges were obviously visible as were two large upper canines.(more than 5 years): Adult females were approximately two thirds the size of adult males. The color of the dorsum, crown to nape, cape area, arms, and outer thighs were brown and changed to a deeper brown with increasing age. The golden guard hairs over the dorsum and cape area were also brilliant but much shorter than those of adult males. Some individuals had very small but visible granulomatous flanges as well. Their breasts and nipples were large and visible.Behavioral observations were conducted from March 2009 to July 2010 for a total of 182 days and 964 hr. The behavioral data were collected in the form of focal animal behavioral sampling a priori the period over which to measure responses to non-reciprocated bouts , our analyses were based only on immediately reciprocated bouts.A grooming bout atarted when one of the two partners initiated the first grooming episode, and ending when the individuals separated from each other, or if no grooming was exchanged for more than 600 s. Episodes were defined as grooming trade-offs within grooming bouts. In a grooming bout, if individual A groomed B and B reciprocated, the bout was composed of two episodes: the episode in which A groomed B and the episode in which B groomed A We recorded copulation behavior by identifying the initiator and receiver. A copulation act involved mounting, including heterosexual genital contact accompanied by intromission and pelvic thrusts For each agonistic event, we recorded the identity of the initiator and the receiver and the behavioral context in which the interaction occurred. Aggressive behavior  and submissive behavior  were both recorded. We calculated the rate of aggressive interaction events per statistical day for each individual.n(n−1) dyads per one-male unit, where n was the number of individuals. However, according to Henzi et al. Weighted logistic regression was conducted to test whether the duration of time the initiator groomed the recipient in the first grooming episode predicted whether the recipient reciprocated or not Maximum likelihood estimation was used to avoid pseudoreplication of clusters containing the same animals R) was calculated R-index, which is a measure of the symmetry of interactions, is calculated by subtracting the total amount of grooming received by a particular individual from the amount of grooming given by that individual, and dividing the result by the total amount of grooming to correct for sample size. GAB is the amount of grooming that individual A gave to individual B, and GBA is the amount of grooming given by individual B to individual A. The R index ranges from −1 to 1, with positive values indicating that partner A gave more grooming than he/she received, a value of 1 representing complete grooming altruism. Negative values indicate that individual B gave more grooming than he/she received, representing selfishness on the part of A. A value of 0 represents even reciprocity. R index results are presented as mean ± SE. We classified the females into different categories. To avoid pseudoreplication of dyads including the same individuals, according to the different trader classes, interactions within a dyad were classified as individuals of A or B separately , and to compare the distributions of reciprocal and non-reciprocal grooming. The dominance hierarchy for females was determined based on the outcome of decided agonistic events between females χ2 = 42.72, p<0.0001). If the initiator invested a longer amount of time in grooming the recipient in the first episode, the probability of grooming reciprocation from the recipient to the initiator within that bout was higher. . During the same bout, the average duration of time that initiator groomed receiver was 288±9.52 s and that receiver groomed initiator was 78±5.53 s . The grooming took up 4.36%±2.28% (mean ± SD) of daily activity, which was calculated by the sum of grooming time divided by the total observed time for each individual . Both males and females demonstrated time matching reciprocated grooming bouts . The total duration of time reciprocated by the recipient was positively correlated with the total duration of time the initiator spent grooming within a bout. The time matching slopes were positive .The correlation between the degree of male grooming reciprocity and the number of females within each one-male unit was significantly negative , with males receiving more grooming from females during the mating season (mean R ± SE = −0.32±0.01) than during the non-mating season . The rate of food- related aggressive interactions per statistical day  was negatively correlated with the duration of grooming that females invested to the resident male in each one-male unit .A very large discrepancy in grooming time was found in male-female dyads. The value of mean sr = 0.54, p = 0.09). Although not statistically significant, this result suggests that an increase in the number of females might increase the odds of reciprocation. Therefore, the female-female dyad data from both the mating season and the non-mating season were analyzed separately to explore the possibility of seasonal effects. Grooming reciprocation was significantly and negatively correlated with the number of females within a one-male unit during the mating season . In the non-mating season, however, the level of reciprocation and the number of females was negatively, but not significantly, correlated . A significant difference in grooming reciprocation during and outside the mating season was obeserved . Approximately 11.1% of females in the study group had no young offspring and did not get pregnant during the year of study. Aggressive interactions occurred at a rate of 0.33 events per statistical day in the mating season and 0.13 outside the mating season. Aggressive interactions were thus not equally distributed during the mating season and outside the mating season . The level of female-female aggression was higher in the mating season than outside of the mating season .Contrary to male-female dyads, the dyads consisting of females showed no significant correlation between grooming reciprocity and the adult sex ratio  within each one-male unit . The mean number of infants per one-male unit was 0.43±0.12 (mean ± SD). The average number of adult females without infants per one-male unit was 2.55±1.47 (mean ± SD). The average number of juvenile females per one-male unit was 0.58±0.72 (mean±SD). A significant negative relationship was observed between non-mother to mother grooming duration and the rate of infants per female in each one-male unit . This relationship indicated that when infants were abundant, grooming durations were shorter; when infants were scarce, grooming durations were longer.A strong discrepancy of grooming was found in dyads consisting of non-mothers and mothers with the R ± SE = 0.01±0.09; t = 2.94, p<0.05).Opposite to the non-mother vs. mother dyads, the dyads of non-mothers represented approximate symmetry on the amount of time they invested in grooming each other within each dyad (mean R ± SE = −0.25±0.05). Moreover, social rank was one of the main factors determining the degree of grooming reciprocation . The level of grooming reciprocation was negatively correlated to the rank distance between females , which meant that, in dyads consisting of distantly ranked females, the degree of reciprocation was lower than that in dyads consisting of closely ranked females .In dyads of high-ranking and low-ranking females, grooming was biased in favor of the former as low-ranking females groomed high-ranking females more than vice versa  displayed no tendency to direct grooming up the hierarchy. They concluded that hamadryad females only traded grooming for itself and showed no evidence for interchange. In addition, the majority of females did not exchange grooming for support from non-relatives Schino R. roxellana, grooming was asymmetric. Grooming disparities suggested that individuals spent more time investing in social relationships with more valuable partners. Power differentials that result from social status can offset strict reciprocation and influence the dynamics of grooming between individuals in non-human primate species. In R. roxellana, reciprocity existed, because partners firmly distributed grooming according to their social standing irrespective of whether grooming reciprocation would occur or not In the studied


We used transmission electron microscopy and immunofluorescence  to provide evidence for the existence of TCs in mice liver. The distribution of TCs in liver was found to be of similar density in the four hepatic lobes. In conclusion, here we show the presence of TCs in mice liver. It remains to be determined the possible roles of TCs in the control of liver homeostasis and regeneration, the more so as a close special relationship was found between TCs and hepatic putative stem (progenitor) cells.Hepatic interstitial cells play a vital role in regulating essential biological processes of the liver. Telocytes (TCs), a novel type of interstitial cells firstly identified by Popescu and his coworkers, have been reported in many tissues and organs, but not yet in liver (go to  Telocytes (TCs) are a novel type of stromal cells of mesenchymal origin firstly identified by Popescu’s group This study was aimed to investigate the existence of TCs in the liver by transmission electron microscopy (TEM) as this technique assures the precise identification of TCs C57/BL6 male mice (25–30 g) aged 10–12 weeks, purchased from Shanghai SLAC Laboratory Animal CO. LTD  were used in this study. The mice were housed in a temperature-controlled facility with a 12 hr light/dark cycle with full access to water and food for at least 1 week for the experiment. This study was approved by the local ethical committees and all animal experiments were conducted under the guidelines on humane use and care of laboratory animals for biomedical research published by National Institutes of Health .3 fragments and fixed by immersion in 5% glutaraldehyde in phosphate buffer  overnight at 4°C. After that, it was washed in phosphate buffer for four times followed by post-fixation with 1% osmium tetroxide in 0.1 M phosphate buffer for 2 hrs at 4°C. Tissues were dehydrated through graded alcohols  for 30 min. each and embedded in Epon 812. Semithin sections were cut at 1.5 μm and stained with toluidine blue, and histologically analysed by light microscopy. Ultrathin sections were cut at 70 nm and contrasted with uranyl acetate and lead citrate, and they were examined with a JEM-1010 electron microscope . Snap-shots were taken using a video camera Veleta and the iTEM Olympus Soft Imaging System .Tissues were cut into 1 mmFrozen sections (6 μm thick) were mounted on Superfrost Plus slides . Sections were fixed in paraformaldehyde for 15 min. After washed with PBS for three times, sections were pre-incubated in PBS supplemented with 10% goat serum for 1 hr, and then incubated overnight at 4°C with rabbit polyclonal anti-c-kit  and rat monoclonal anti-CD34 . Both antibodies were diluted by 1:100 in 1× PBS with 0.25% Triton X-100. After that, sections were exposed for 1 hr to goat anti-rat labelled with FITC  and goat anti-rabbit labelled with rhodamine secondary antibodies  diluted by 1:200 in the same buffer. Finally, sections were stained with 4′,6-diamidino-2-phenylindole (DAPI) . The same protocol was used in Rabbit polyclonal to PDGF Receptor-alpha , Rabbit monoclonal to PDGF Receptor-beta  and Rabbit monoclonal to Vimentin .Representative sections of the left lateral, right, median and caudate lobes of mice livers were used for immuofluorescent staining. For the semi-quantification of hepatic TCs, double staining for c-kit and CD34 was used. Each lobe of the liver was randomly obtained of 20 images (400×) in the central area using confocal laser scanning microscope . The anti-c-kit and CD34 images from the same field were merged by Zen 2011 software (Carl Zeiss MicroImaging GmbH). Three mice were used in this experiment. Counting of the hepatic TCs was performed in a double-blinded method. The density of TCs was expressed as TCs number/number of DAPI-stained nuclei.anova was conducted to evaluate the one-way layout data. If a significant difference was observed, Bonferroni’s post hoc test was conducted to identify groups with significant differences. All analyses were performed with SPSS 17.0,  and all statistical tests were two-sided. P-values that were less than 0.05 were considered to be statistically significant.Data were presented as mean ± SD. A one-way Transmission electron microscopy examination is a golden standard for the identification of TCs Immunofluorescence is also of importance to determine the phenotype of TCs P = 0.823). Therefore, no significant difference appeared.A similar distribution of TCs was found in the four hepatic lobes, when expressed as TCs number/number of DAPI-stained nuclei: namely, as percentage: 1.7 ± 0.6% left lateral lobe; 1.8 ± 0.5% median lobe; 1.9 ± 0.5% right lobe; 1.8 ± 0.6% caudate lobe  in liver by their location, morphology and immunophenotypes. Kupffer cells are located inside the sinusoids i) intercellular connections via Tps ii) intercellular signalling via shedding vesicles or paracrine secretion iii) liver regeneration as was supported for heart The precise functions of TCs in liver remain to be established. However, based on the literature, at least three relevant and potential roles could be proposed: (In conclusion, this study firstly demonstrated the presence of TCs in liver based on the specific ultrastructural and immunofluorescent characteristics. The presence of TCs in the liver opens a new window for better understanding responses that have not been determined in hepatic biology. Telocytes may be a new kind of target cells for the treatment and prevention of liver diseases.


Impairment in activities of daily living (ADL) is an important predictor of outcomes although many administrative databases lack information on ADL function. We evaluated the impact of ADL function on predicting postoperative mortality among older adults with hip fractures in Ontario, Canada.Sociodemographic and medical correlates of ADL impairment were first identified in a population of older adults with hip fractures who had ADL information available prior to hip fracture. A logistic regression model was developed to predict 360-day postoperative mortality and the predictive ability of this model were compared when ADL impairment was included or omitted from the model.The study sample  had a mean age of 85.2 years, were 72.8% female and the majority resided in long-term care (78.5%). Overall, 36.4% of individuals died within 360 days of surgery. After controlling for age, sex, medical comorbidity and medical conditions correlated with ADL impairment, addition of ADL measures improved the logistic regression model for predicting 360 day mortality .Direct measures of ADL impairment provides additional prognostic information on mortality for older adults with hip fractures even after controlling for medical comorbidity. Observational studies using administrative databases without measures of ADLs may be potentially prone to confounding and bias and case-mix adjustment for hip fracture outcomes should include ADL measures where these are available. Several disease processes can lead to functional impairments in basic activities of daily living (ADLs)  and impaComorbidity indices, such as the Charlson comorbidity score ,21, the One potential method to control for confounding due to ADL impairment is to control for variables that are available in most administrative databases such as demographics, medical conditions ,26-28, aTo identify medical conditions and other correlates of functional impairment we searched electronic databases using key words and medical subject headings  or clinical presentations . For example, we excluded correlates of functional impairment that involved measurement of variables such as laboratory values and physiological measurements such as blood pressure which are not routinely available in administrative data. Activities of daily living are classified into basic activities of daily living  and instrumental activities of daily living  . ImpairmMethods for measuring each of the variables correlated with ADL impairment were identified using linked administrative healthcare databases situated at the Institute for Clinical Evaluative Sciences (ICES). These data sets were held securely in a linked, deidentified form and analysed at ICES. These datasets included the Registered Persons Database (RPDB) for demographic variables and date of death, the Canadian Institute for Health Information (CIHI) National Ambulatory Care Reporting System (NACRS) and Discharge Abstract Database (DAD) for emergency department visits and hospital admissions, respectively; the Ontario Health Insurance Plan (OHIP) claims database for outpatient and inpatient claims and assessments; and the Ontario Drug Benefits (ODB) database to identify claims for outpatient prescription medications; and the Ontario Mental Health Reporting System (OMHRS) for mental health inpatient admissions. These databases are routinely used for research purposes and the accuracy of these databases have been detailed in previous reports ,32.Our study population included all adults aged 66 or older who underwent hip fracture surgery  in Ontario between April 1, 2003 and March 31, 2009. The correlates of functional impairment were determined using hospital discharge diagnostic codes, diagnostic codes associated with outpatient physician visits, and prescribed medications  was utilized for all analyses.To determine whether medical conditions or other measures in administrative data were correlated with functional impairment, we performed a series of linear regression analyses with ADL long-form total scores as the dependent variable and each potential correlate as the independent variable. Variables associated with ADL impairment with a p-value of <0.05 were then retained for future models and the proportion of the variance of ADL impairment explained by the variable was assessed by the value of the R2 statistic. Then, a multivariable logistic regression model was constructed to predict the probability of 360-day postoperative mortality. We first added age, sex, and residence in LTC in sequence to the model. Next, the measures of medical comorbidity and health service utilization that were significantly correlated with ADL impairment in the study sample were added to the model. Finally, all the medical conditions that were correlated with ADL impairment were included in the model. Direct measures of ADL impairment were then added to model using dummy variables for the previously defined categories of ADL impairment. The predictive ability of the model was assessed by the c-statistic and the maximum rescaled R2 values obtained for the models with and without ADL impairment. To assess whether ADL impairment improved the model fit, the change in the -2 log likelihood values for the models with and without ADL impairment were compared using a χ2 test for with a degrees of freedom equal to the number of additional variables in the models with ADL impairment compared to the models without ADL impairment. The AIC value for the models with and without ADL impairment were also compared as another method to assess improvement in model fit with a reduction in AIC indicating improved model fit. In all of our models, we ensured that the number of events  were sufficient for the number of covariates in order to avoid over-fitting the model using a minimum of 10 events for each covariate included [We selected 360-day mortality following hip fracture surgery as death is common in the year following hip fracture surgery with approximately 30% of older adults experiencing this outcome . Follow-included . There wA total of 195 potentially relevant articles were identified from the electronic database search, 25 articles were identified through reference lists and 4 review articles were identified ,28,51. AA total of 23 conditions were reported to be associated with impairment in basic ADLs  or a RAI-MDS assessment  in the 90 days preceding hospitalization for hip fracture surgery (Table 2 statistic were residence in LTC (R2 = 0.11) and dementia (R2 = 0.05), while the other variables were associated with smaller R2 values.In univariate linear regression analyses, several individual medical conditions or measures of medical comorbidity were associated with ADL impairment Table . Variabl2 = 0.005). Addition of LTC residence increased R2 value to 0.12. Further addition of Charlson score, number of major ADGs, and outpatient visits had a minimal effect on the adjusted R2 = 0.13. Addition of medical conditions associated with ADL impairment also only had a small effect on the overall adjusted R2 value, which was 0.16 for the final model  died within the 360 days of hip fracture. The severity of ADL impairment was positively correlated with mortality. Individuals with an ADL score of between 0 – 5 had a mortality risk of 25.8% when compared to a risk of mortality of 43.6% for individuals with an ADL score of > 20 with intermediate categories of ADL impairment associated with a gradation in the risk of mortality . However, this logistic regression model with only ADL impairment had a weak discriminative ability (c-statistic of 0.578) and only explained a low proportion of the variation in mortality   and maximum rescaled R2 (0.11 vs. 0.09).Impairment in ADLs was strongly associated with mortality in a logistic regression model (OR = 2.22; 95% CI: 1.54 – 3.23; χWe also completed a sensitivity analysis to identify correlates of ADL impairment using backward selection in two models using P-values 0.1 and 0.05 to identify correlates. After identifying variables correlated with ADL using these models, the addition of direct measures of ADL impairment to the final model predicting mortality resulted in improved predictive ability of the model as determined changes in the AIC, -2 log likelihood ratio and c-statistic similar to the primary analysis.In the current study, a number of medical conditions that are routinely recorded in administrative data and other variables were identified as being correlated with functional impairment in older adults who underwent hip fracture surgery. Impairment in basic ADLs was significantly associated with an increased risk of mortality in the year following hip fracture with a 2-fold increase in the risk of death for individuals with greatest ADL impairment as compared to those with the least amount of impairment. Importantly, even after controlling for medical comorbidity and medical conditions correlated with ADL impairment, direct measures of ADL impairment added significantly to the prediction of postoperative mortality. This suggests that measures to control for the effects of ADL impairment through use of conditions associated with functional impairment and medical comorbidity may not be sufficient when direct measures of ADL impairment are not available potentially resulting in confounding or bias in observational studies.These findings are consistent with previous research demonstrating that ADL impairment is a significant predictor of mortality and other poor health outcomes for populations of older adults with hip fractures ,40. SeveWhen the outcome of mortality in the 360 days following hip fracture surgery was examined, ADL function was significantly associated with mortality in a dose response relationship. Impairment in ADLs has been demonstrated to be a predictor of postoperative mortality in older adults with hip fractures, along with several other risk factors ,40. Whil2 and c-statistics. The importance of ADL impairment in predicting outcomes after adjusting for medical comorbidity has also been observed in observational studies of older adults undergoing cardiac surgery [Prior studies have also demonstrated that studies utilizing administrative datasets with direct measures of functional status can significantly add to statistical models predicting outcomes such as death, institutionalization, or hospitalization . A study surgery  and comm surgery . LikewisThere are some limitations to the current study. The first relates to the study population, the majority of which were in LTC prior to cohort entry along with community-dwelling older adults who received home care services. Given the high rates of functional impairment in these populations, the results observed in our study may not generalize well to other study populations with less severe levels of impairment such as community-dwelling older adults who are not receiving home care services. Some clinical variables associated with ADL impairment such as abnormal laboratory values or measures of strength were not available in our datasets and as such these could not be included in our statistical models. Finally, some conditions such as malnutrition are likely underreported in our administrative databases when compared to detailed chart review or clinical examination  and our In summary, impairment in basic activities of daily living can be an important predictor of outcomes in observational studies using administrative databases. There is the potential for residual confounding due to ADL impairment when direct measures of ADL functioning are not available, even after controlling for demographics, medical comorbidity, and medical conditions correlated with ADL impairment. Additional studies of populations other than older adults with hip fractures will be useful to further understand the impact of ADL impairment on outcomes in observational studies using administrative healthcare datasets.The authors of this manuscript have no conflicts of interest to declare.All authors made substantial contributions to the conception and design of the study. DS contributed to the analysis of data. DS drafted the manuscript and all authors revised it critically for content. The final manuscript was approved by all authors.The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2318/14/9/prepubSearch terms used in search strategy.Click here for fileCorrelates of functional impairment in older adults.Click here for fileReference list for conditions associated with impairment in activities of daily living.Click here for file


Lack of proper auditory feedback in hearing-impaired subjects results in functional voice disorder. It is directly related to discoordination of intrinsic and extrinsic laryngeal muscles and disturbed contraction and relaxation of antagonistic muscles. A total of twenty children in the age range of 5–10 years were considered for the study. They were divided into two groups: normal hearing children and hearing aid user children. Results showed a significant difference in the vital capacity, maximum sustained phonation, and fast adduction abduction rate having equal variance for normal and hearing aid user children, respectively, but no significant difference was found in the peak flow value with being statistically significant. A reduced vital capacity in hearing aid user children suggests a limited use of the lung volume for speech production. It may be inferred from the study that the hearing aid user children have poor vocal proficiency which is reflected in their voice. The use of voicing component in hearing impaired subjects is seen due to improper auditory feedback. It was found that there was a significant difference in the vital capacity, maximum sustained phonation (MSP), and fast adduction abduction rate and no significant difference in the peak flow. Lack of proper auditory feedback in hearing-impaired subjects results in functional voice disorder. It is directly related to discoordination of intrinsic and extrinsic laryngeal muscles and disturbed contraction and relaxation of antagonistic muscles. Generally, the voice organ of a hearing-impaired child shows no anatomical abnormalities in the first years of life. Data in the literature suggest that the impairment of the voice organ is a secondary effect and results not only from abnormal auditory feedback but also from inappropriate hearing, voice, and speech rehabilitation in early childhood, or even its cessation , 2. Research on the physiopathology of voice and speech in hearing-impaired children proves that a physiological deficiency of the larynx affects phonation and articulation. Specialists therefore emphasize that voice and speech rehabilitation should begin as soon as possible, helping to maintain correct functioning of the larynx , 4. ChanEarly intervention of hearing impairment has brought a revolution in our society in helping the hearing-impaired children to acquire speech and language utilizing their critical age. Hence, the development of speech and language in hearing children depends on the age of intervention. There is literature which supports the differences in voice quality in normal and hearing-impaired persons both acoustically and aerodynamically. But still, there are poor attempts in studying the voice quality of hearing aid user children and normal children in Indian population. So, there is a need to compare the laryngeal aerodynamic parameters in normal and hearing-impaired children, which will help the speech language pathologist to monitor the changes in the voice quality in pre- and posttherapeutic process. This study will also show light to the correlation between speech and language development with the voice quality of the hearing-impaired children.To compare the laryngeal aerodynamic parameters in age matched hearing aid user children with normal children.A total of 20 children in the age range of 5–10 years, with a mean age of 8 years (SD = 1.5 years) and with an average height of 118.4 cm (SD = 2.32 cm), were considered for the study. They were divided into two groups: normal and hearing aid user children, with 10 children in each group.The hearing aid user children had bilateral profound sensorineural hearing loss, used multichannel binaural digital hearing aids, comprehend and express simple sentence, and followed bidirectional verbal instruction.Children having chronic medical problems, history of voice problems or laryngeal pathology, or any respiratory diseases for the last 3 months and syndromic children were excluded from the study.Aerophone II   was used for assessing the laryngeal aerodynamic properties. It takes the advantage of a sophisticated combination of a hardware transducer system with transducers recording airflow, air pressure, and acoustic signal and a computerized data processing. All electronics including the microprocessor and the transducers are miniaturized and built into a small box mounted in the holder for handle and mask.  Calibration of air pressure: a calibration factor for the air pressure is not necessary as it is fairly stable and not influenced by patients' responses. The air pressure transducer is adjusted from the factory and does not need any further adjustment.For calibrated SPL recordings from aerophone, the microphone is factory tested  and the appurtenant calibration factor is 0.72. If no calibration factor is typed when the programme asks for a calibration factor to ensure the SPL values are exact (within ±0.2 dBSPL), a default calibration factor is used which is an average of several microphone calibration factors as measured by F-J Electronics. To ensure that the microphone measures correctly, the microphone was pushed so far through the PVC rubber sleeve that all the side holes are free. Microphone positions for range 30–80 dB in flow head, 50–100 dB in flow head, 70–120 dB in flow head.For airflow calibration, 1 liter calibration syringe  was taken. While calibrating the approximately one second airflow for big flow head and approximately four seconds for the small flow head was taken. The piston of the syringe was pressed with a constant and a stable movement during the calibration. The calibration was started with a coarse calibration making 3–5 measurements with the 1 liter syringe. When the result was within 1-2% from the correct value, a new calibration with several successive recordings was done. The programme calculated the average calibration factor of the recordings made, which is stored in the setup file. The same procedure was repeated for both flow heads.Warm-up time: the airflow and pressure transducers need approximately 15 minutes in order to obtain a stable zero line after the system has been turned on. After that time the auto zeroing circuit is able to keep the zero line stable during normal recording sessions, which normally do not exceed 60 seconds. When not recording, the system is constantly auto zeroing.Room temperature: the room temperature was kept at 29°C which was measured by the digital thermometer provided in the instrument suitcase. It was recommended to keep the room temperature between 10°C and 40°C.Viscosity of air: when the expired air passes the gauze in the flow head, it has a temperature of 35°C as the air is cooled 2°C below body temperature when passing the speech organs and the flow head tubes. The software takes the changed viscosity of the expired air into account. Calibration of the equipment was done as per Aerophone II manual (2005).Four aerodynamic parameters were taken for assessment: peak flow, vital capacity, maximum sustained phonation, and fast adduction abduction rate. For the measurement of the parameters, separate instructions for separate parameters were demonstrated and repeated to the subjects till they get thorough about it. Throughout the data registration, the height and posture of the client were considered and care was taken to fix the mask and cardboard tube of aero phone properly, so that no air leakages happen.Following procedures were used to measure the following parameters.(1) Vital CapacityThe following setting was made in the programme as per the instruction given in the manual which were kept constant for all subjects. Flow head F1000LS was used for the registration with pressure setting of flow range 0–10 l/sec.The subject was asked to inhale as deep as possible and then to exhale all the airs through the mouth tube until the lungs are completely empty. The registration was made in standing position. It was told to take care that the lips close airtight round the disposable mouth tube. The nose clamp was used during the registration. The instructions were repeated whenever needed and demonstrations were made.The subject exhaled into the mouth tube and the data was stored in the computer. Each subject was asked to give three trials and the highest was considered as the vital capacity for that subject. Thus the vital capacity and its duration were calculated.(2) Peak FlowThe following setting was made in the programme as per the instruction given in the manual which were kept constant for all subjects.Flow head F1000LS was used for the registration with pressure setting of flow range 0–10 l/sec.The subject was asked to inhale as deep as possible and then to exhale all the air through the mouth tube as fast and as strong as possible. The registration was made in standing position. It was told to take care that the lips close airtight round the disposable mouth tube. The nose clamp was used during the registration. The instructions were repeated whenever needed and demonstrations were made.The subject exhaled into the mouth tube and the data was stored in the computer. Each subject was asked to give three trials and the highest value was considered for that subject. Thus the peak flow, forced volume 1 second and Duration was calculated from the result.(3) Maximum Sustained PhonationThe following setting was made in the programme as per the instruction given in the manual which were kept constant for all subjects.Flow head F 300LS was used with pressure setting of 5.0 l/s and 50–100 dB was selected from the SPL menu.As the subjects taken, consisted of males, hence the pitch level was set at 131 Hz, with an intensity range of 75 dB.The subject was asked to fix the mask covering mouth and nose over the face and was asked to take care that there was no leakage through the mask during the measurement. The subjects were instructed to take a deep breath and try to produce a matching tone produced by the computer, maintaining its loudness. They could use the indicator (computer monitor) to maintain the loudness. The subjects were asked to say /a/ as long as and as comfortable as possible.The instructions were repeated whenever needed and demonstrations were made.After the phonation, the data were stored in the computer.(4) Fast Abduction-Adduction Rate The following setting was made in the programme as per the instruction given in the manual which were kept constant for all subjects. Flow head F300LS was used with pressure setting of 1.00 l/s and intensity range was 30–80 dB close.  The subject was asked to fix the mask covering mouth and nose over the face and was asked to take care that there was no leakage through the mask during the measurement.ah ah ah ah” as fast as possible after taking in deep breath. The voiced production was recorded. The subjects were instructed to say “ The instructions were repeated whenever needed and demonstrations were made. After the recording, the data of volume, mean airflow rate, and adduction abduction rate were stored in the computer.The aerodynamic scores analysis for peak flow for normal children showed a mean value of 1.4682 litre/sec, (SD = 0.386 litre/sec) as compared to hearing aid user children, who showed a mean value of 1.202 litre/sec (SD = 0.348 litre/sec) .t-test results showed no significant difference in the peak flow value with (t (18) = 1.618, P = 0.123) being statistically significant at 95% level of confidence  as compared to hearing aid user children, who showed a mean value of 0.454 litre/sec (SD = 0.058 litre/sec) .t-test results showed a significant difference in the vital capacity (t (17) = 7.153, P = 0.00), being statistically significant at 95% level of confidence  as compared to hearing aids user children, who showed a mean value of 4.327 seconds (SD = 0.736 seconds) .t-test results showed a significant difference in the maximum sustained phonation (t (18) = 20.096, P = 0.00) being statistically significant at 95% level of confidence , respectively, as compared to hearing aid user children, who showed a mean value of 5.790 cycles/second (SD = 3.122 cycles/second) .t-test results showed a significant difference in the fast adduction abduction rate for normal and hearing aid user children with (t (18) = 7.050, P = 0.00) being statistically significant at 95% level of confidence , and fast adduction abduction rate . Althoug Peak flow otherwise known as peak expiratory flow (PEF) is the maximum flow achieved during an expiration delivered with maximal force starting from the level of maximal lung inflation. Measurements of PEF are of value in identifying airflow limitation . An abseVital capacity is the total amount of air that can be exhaled after a maximum inspiration . A reducMaximum sustained phonation is considered a maximum performance task which measures a person's ability to efficiently manage an adequate air supply during phonation . MSP is The parameter fast adduction abduction rate indicates the rate of closing and opening movements of vocal fold in movements per second. The pronunciation may be either voiced or voiceless, but the result will differ from each other in each case. The use of voicing component in hearing-impaired subjects is seen due to improper auditory feedback. Hence, a difference in the adduction abduction rate is observed in the hearing aid users. Forner and Hixon  reportedVarious findings have been documented in the literature regarding the laryngeal aerodynamic characteristics of hearing-impaired children. Although the basis of breathing anomalies and abnormal pausing in these cases are not understood, it could be related to aberrant functioning at all levels of the speech mechanism including the respiratory, phonatory, articulatory, and resonatory speech subsystems. Compared to speakers with normal hearing, speakers with bilateral congenital profound hearing impairment tend to initiate speech at a level of lung volume that is either too high or too low and to speak into functional reserve capacity; moreover, the mean airflow per syllable is twice that of speakers with normal hearing which is reflected in our findings of reduced vital capacity and adduction abduction rate. Profoundly hearing-impaired speakers also demonstrated more aberrant rates of oral airflow than did normal-hearing (NH) and severe hearing-impairment (SHI) speakers. Consequently, these speakers produced fewer syllables per breath group and often paused for inspiration at grammatically inappropriate locations. The authors concluded that the disorders in the speech respiratory behaviors resulted from the combined influences of poor respiratory control, incoordination between larynx and upper airway, and/or failure to follow grammatical phrasing.Laryngeal dysfunction has been documented in speakers with hearing impairments. Using transillumination to monitor glottal activity and an electrical transconductance technique to record temporal patterns of oral articulation, McGarr and Löfqvist  studied Aberrant pausing in SHI may also be due to aberrant articulatory and velopharyngeal behavior. Specifically, SHI speakers tend to speak slower and exhibit more nasality than NH speakers. Slowed speech is probably associated with increased pauses as speakers need to replenish their air supply more frequently. Similarly, air escape from the velopharyngeal port during speech could diminish the air supply for speech, resulting in more frequent inspirations. The purpose of this investigation is to identify the potential components of the abnormal pausing patterns. This information will serve as a basis for more in-depth investigations into speech subsystem changes that might account for the observed behavior.Speech breathing anomalies in speakers with SHI have commonly been characterized using kinematic or aerodynamic technology. It has been shown that speakers with SHI exhibit more inappropriate inspiratory loci; in addition, they tend to inspire at nongrammatical locations when reading passages, apparently because of improper respiratory control. Aberrant pausing patterns could affect its temporal breath group structure, speaking rate within breath groups, and speech intelligibility. Correlations between different heights of the children and aerophone parameters should also be established for the hearing-impaired children with respect to their normal hearing counterparts. This information will serve as a basis for more in-depth investigations into speech subsystem changes that might account for the observed behavior.


The prostate comprises a glandular epithelium embedded within a fibromuscular stroma. The stroma is a complex arrangement of cells and extracellular matrix (ECM) components in addition to growth factors, regulatory molecules, remodelling enzymes, blood vessels, nerves and immune cells. The principal sources of ECM components are fibroblasts and smooth muscle cells (SMC), which synthesize the structural and regulatory components of the ECM. Telocytes (TCs) were recently described as a novel stromal cell type that exhibited characteristic features. The aim of this study was to confirm the presence of TCs in prostate stromal tissue of gerbils, as the stromal compartment of this gland is a dynamic microenvironment. We used transmission electron microscopy (TEM), light microscopy and immunohistochemistry methods to provide morphological evidence for the presence of TCs. Cells that resembled TCs were observed in gerbil prostatic stroma. These cells had small cellular bodies with very thin and extremely long cellular processes. They were found primarily in the subepithelial area and also at the periphery of SMC layers. TCs also exhibited moniliform processes, caveolae and nuclei surrounded by small amounts of cytoplasm. Close contacts between TC podomers were evident, particularly in the adjacent epithelial compartment. This morphological evidence supported the presence of TCs in the gerbil prostatic stroma, which we report for the first time. The prostate is an important accessory gland that is located in the mammalian genital tract. In conjunction with seminal vesicles, it produces the bulk of seminal fluid . This glvia stromal–epithelial interactions [The principal sources of ECM components are fibroblasts and smooth muscle cells (SMC), which synthesize the structural and regulatory components of the ECM , 3. The ractions , 5. Thusractions .However, during ageing in humans and several other species, including dogs and some rodent strains, cellular hyperplasia may occur despite a decrease in the production of sexual hormones, such as testosterone, which results in age-dependent prostatic hyperplasias . These aet al. [Meriones unguiculatus) after blocking steroidogenic enzymes. These changes included the accumulation of fibrillar components and phenotypically altered SMCs and fibroblasts. However, detailed, specific information on these cells' morphologies and immunophenotypes has not been acquired.Studies of the human prostate, as well as of breast and colon cancer specimens, have identified stromal cells that are phenotypicaly altered cells, primarily fibroblasts and SMCs, in addition to modified ECM compositions, including new formation and deposition of abundant fibrillar collagens and increased capillary density , 8. Corret al. , 10 noteet al. [A novel stromal cell type was recently described. Popescu et al. , 12 noteet al. –13.in vitro (isolated cells in culture) and in vivo (fixed specimens) techniques and light, fluorescent, transmission and scanning electron microscopic have been used to characterize these cells morphologically [Various ogically , 14. Alsogically –17. Howeogically . TCs havogically , 17–19, ogically , gallblaogically , uterus ogically –24, meseogically , pulmonaogically , tracheaogically , 28, pleogically , placentogically , skeletaogically , exocrinogically , skin [3ogically , mammaryogically  and paroogically .The identification of TCs, which have remarkably long, thin and moniliform processes, is based primarily on the recognition of Tp's . These TThe aim of this study was to confirm the presence of TCs in the prostatic stroma of gerbils, used as a rodent experimental model , 9, 10. Meriones unguiculatus, Gerbilinae, Criscetidae) were housed under controlled conditions of temperature (25°C), relative humidity (40–70%) and light (12-hr light-dark cycle), and were allowed free access to standard chow and water. Gerbils were first weighed (≍80.0 gm), anaesthetized by CO2 inhalation and decapitated. The prostatic complex was dissected out, weighed and fixed according to the different protocols described below. The ventral prostate was carefully dissected out, weighed and fixed. Animal handling and experiments were in accordance with the guidelines of the Ethics Commission for Animal Experimentation (CEEA) of Campinas State University – UNICAMP, São Paulo, Brazil (Process no.: 1236-1), which followed the Guide for Care and Use of Laboratory Animals.Thirty adult male gerbils  for 24 hrs or immediately frozen in liquid nitrogen for later cryosectioning. After fixation, tissues were washed with running tap water, dehydrated in a graded ethanol series and embedded in glycol methacrylate resin . Some prostatic fragments were fixed in 4% formaldehyde freshly prepared in phosphate buffer (pH 7.2) for 24 hrs. These were also dehydrated in a graded ethanol series and embedded in Paraplast . Tissue sections (3–4 μm) were obtained using a Leica automatic rotary microtome . For general studies, histological sections were stained with haematoxylin and eosin . MicroscProstate ventral lobe fragments were minced into small pieces and fixed by immersion in 3% glutaraldehyde plus 0.25% tannic acid solution in Millonig's buffer, pH 7.3, containing 0.54% glucose for 24 hrs . After wTo provide evidence for TCs among several stromal structures of the gerbil prostate, we digitally coloured these cells on electron photomicrographs to make TCs more visible. All elements were carefully hand coloured using Adobe Photoshop software .2O2 in methanol for 30 min. Then, sections were washed in PBS and incubated with 3% BSA for 1 hr. Incubation with a primary antibody was at 4°C overnight, followed by incubation with a peroxidase-labelled polymer  for 60 min. and incubation with a substrate chromogen  for 15 min. Between each step, sections were thoroughly rinsed three times with phosphate buffered saline, pH 7.2. Counterstaining for nuclei was with haematoxylin for 10 sec. The primary antibody used for TCs was anti-CD34 . Negative controls omitted the primary antibody. Images were acquired using an Olympus BX 60 microscope equipped with an Olympus digital camera (Olympus).We used 5-μm-thick cryosections for immunohistochemical analysis. Endogenous peroxidase activity was blocked using 0.3% HAs shown in In the area adjacent to the epithelium, TCs were readily identified as small bodies with thin, long processes that were characteristic of the structures of Tp's. Also, the same types of cells were noted at the periphery of the SMC layer. The small body of TCs could assume a piriform, spindle or triangular shape and Tp's that extended from the body were thin .Electron microscopy analysis confirmed the presence of cells having the ultrastructural features of TCs in the gerbil prostatic stroma A–K. ThesThe major characteristics of the TC cell body are scarce cytoplasm around the nucleus and its spindle shape. The ultrastructural TC pattern in the stroma of the gerbil prostate exhibited a small, spindle-shaped body and two to three thin, very long Tp's, with some that were in close contact similar to adherens junctions C–H. In aContacts between Tp's were found, especially among TCs in the subepithelial area. Regular moniliform processes, with alternating thin segments  and podoms . In addition, these regions were rich in caveolae, endoplasmic reticulum and mitochondria, as observed for TCs in heart tissues , 16 and Immunohistochemistry has been performed for the gerbil prostate and TCs might show different immunohistochemical profiles among organs and even in the same organ. Bucharest's group tested numerous antibodies in an effort to find a single marker that could be considered specific for this cell type or, at least, specific for the TCs of a given organ. Determining the phenotype(s) of TCs is of fundamental importance, as this would provide for their unequivocal identification and would also aid in evaluating their size, shape, number and, ultimately, their movements, migration and pathological changes .C-kit-positive interstitial Cajal cells have been demonstrated in the human prostate , and a vSeveral roles have been suggested for TCs, most of which are plausible and not mutually exclusive. However, to date, none of these have been totally proven. As reported by Popescu and Faussone-Pellegrini , TCs migCardiac TCs have been suggested as having a nursing role, and those in the oviduct and myometrium are suggested to be sensors of steroid hormones . For theThe TCs that appear in the subepithelial region along with those observed at the periphery of smooth muscle might ensure the homeostasis of the stromal compartment for generating the compartmentalization of prostatic tissue microenvironments. Studies of the lower urinary tract demonstrated that the guinea pig prostate contained a network of c-kit-positive interstitial cells that was between the glandular and stromal muscle layers of individual prostatic acini as well as between individual SMCs of the stroma , 12. TheTelocytes might be novel target cells for the prevention and treatment of disease. This novel cell type within the prostatic microenvironment has become an important tool for our research group, as it provides insights into numerous unanswered questions regarding the biology of the prostate and the effects of endocrine disrupting chemicals on the prostatic stroma. The functions and pathology involving TCs in the prostate will require further studies, including studies on benign prostatic hyperplasia and cancer. Investigating the biological functions of TCs within the prostate is important, as the stromal compartment plays key roles in both normal and abnormal tissues. The presence of TCs in the stroma of the gerbil prostate provides a new tool for understanding responses that have not yet been determined in prostate biology. The purpose of this study was primarily to confirm the presence of a novel cell type, TCs, in the prostate based on the specifics of their ultrastructural and immunohistochemical characteristics.