Mutations in protocadherin 15 and cadherin 23 affect tip links and mechanotransduction in mammalian sensory hair cells

Immunocytochemical studies have shown that protocadherin-15 (PCDH15) and cadherin-23 (CDH23) are associated with tip links, structures thought to gate the mechanotransducer channels of hair cells in the sensory epithelia of the inner ear. The present report describes functional and structural analyses of hair cells from Pcdh15av3J (av3J), Pcdh15av6J (av6J) and Cdh23v2J (v2J) mice. The av3J and v2J mice carry point mutations that are predicted to introduce premature stop codons in the transcripts for Pcdh15 and Cdh23, respectively, and av6J mice have an in-frame deletion predicted to remove most of the 9th cadherin ectodomain from PCDH15. Severe disruption of hair-bundle morphology is observed throughout the early-postnatal cochlea in av3J/av3J and v2J/v2J mice. In contrast, only mild-to-moderate bundle disruption is evident in the av6J/av6J mice. Hair cells from av3J/av3J mice are unaffected by aminoglycosides and fail to load with [3H]-gentamicin or FM1-43, compounds that permeate the hair cell's mechanotransducer channels. In contrast, hair cells from av6J/av6J mice load with both FM1-43 and [3H]-gentamicin, and are aminoglycoside sensitive. Transducer currents can be recorded from hair cells of all three mutants but are reduced in amplitude in all mutants and have abnormal directional sensitivity in the av3J/av3J and v2J/v2J mutants. Scanning electron microscopy of early postnatal cochlear hair cells reveals tip-link like links in av6J/av6J mice, substantially reduced numbers of links in the av3J/av3J mice and virtually none in the v2J/v2J mice. Analysis of mature vestibular hair bundles reveals an absence of tip links in the av3J/av3J and v2J/v2J mice and a reduction in av6J/av6J mice. These results therefore provide genetic evidence consistent with PCDH15 and CDH23 being part of the tip-link complex and necessary for normal mechanotransduction

Image Texture Characterization Using the Discrete Orthonormal S-Transform

We present a new efficient approach for characterizing image texture based on a recently published discrete, orthonormal space-frequency transform known as the DOST. We develop a frequency-domain implementation of the DOST in two dimensions for the case of dyadic frequency sampling. Then, we describe a rapid and efficient approach to obtain local spatial frequency information for an image and show that this information can be used to characterize the horizontal and vertical frequency patterns in synthetic images. Finally, we demonstrate that DOST components can be combined to obtain a rotationally invariant set of texture features that can accurately classify a series of texture patterns. The DOST provides the computational efficiency and multi-scale information of wavelet transforms, while providing texture features in terms of Fourier frequencies. It outperforms leading wavelet-based texture analysis methods

Impact of time since last caloric intake on blood glucose levels

Blood glucose (BG) is usually measured after a caloric restriction of at least 8 h; however evidence-based recommendations for the duration of a fasting status are missing. Here we analyze the effect of fasting duration on levels of BG to determine the minimal fasting duration to achieve comparable BG levels to conventional fasting measurements. We used data of a cross-sectional study on primary care patients, performed in October 2005. We included 28,024 individuals (age-range 18–99 years; 63% women) without known diabetes mellitus and without missing data for BG and fasting status. We computed general linear models, adjusting for age, sex, time of blood withdrawal, systolic blood pressure, waist circumference, total- and HDL-cholesterol, physical activity, smoking, intake of beta-blocker and alcohol. We tested the intra-individual variability with respect to fasting status. Overall, the mean BG differed only slightly between individuals fasting ≥8 h and those fasting <8 h (men: 5.1 ± 0.8 mmol/L versus 5.2 ± 1.2 mmol/L; women: 4.9 ± 0.7 mmol/L, 5.0 ± 1.0 mmol/L). After 3 h of fasting differences of BG diminished in men to −0.08 mmol/L (95%-CI: −0.15; −0.01 mmol/L), in women to −0.07 mmol/L (−0.12; −0.03 mmol/L) compared to individuals fasting ≥8 h. Noteworthy, age, time of day of blood withdrawal, physical activity, and intake of hard liquor influenced BG levels considerably. Our data challenge the necessity for a fasting duration of ≥8 h when measuring blood glucose, suggesting a random sampling or a fasting duration of 3 h as sufficient. Rather, our study indicates that essentially more effort on the assessment of additional external/internal factors on BG levels is necessary

Symbolic meanings and e-learning in the workplace: The case of an intranet-based training tool

This article contributes to the debate on work-based e-learning, by unpacking the notion of ‘the learning context’ in a case where the mediating tool for training also supports everyday work. Users’ engagement with the information and communication technology tool is shown to reflect dynamic interactions among the individual, peer group, organizational and institutional levels. Also influential are professionals’ values and identity work, alongside their interpretations of espoused and emerging symbolic meanings. Discussion draws on pedagogically informed studies of e-learning and the wider organizational learning literature. More centrally, this article highlights the instrumentality of symbolic interactionism for e-learning research and explores some of the framework’s conceptual resources as applied to organizational analysis and e-learning design. </jats:p

Expression of MAGE-C1/CT7 and MAGE-C2/CT10 Predicts Lymph Node Metastasis in Melanoma Patients

MAGE-C1/CT7 and MAGE-C2/CT10 are members of the large MAGE family of cancer-testis (CT) antigens. CT antigens are promising targets for immunotherapy in cancer because their expression is restricted to cancer and germ line cells and a proportion of cancer patients presents with immune responses against CT antigens, which clearly demonstrates their immunogenicity. This study investigates the expression of MAGE-C1/CT7 and MAGE-C2/CT10 in primary and metastatic melanoma. Immunohistochemical staining of tissue microarrays that consisted of 59 primary malignant melanomas of the skin, 163 lymph node and distant melanoma metastases and 68 melanoma cell lines was performed. We found MAGE-C1/CT7 expression in 15 out of 50 (24%) primary melanomas and 15 out of 50 (24%) cell lines, whereas MAGE-C2/CT10 was detected in 17 out of 51 (33%) primary melanomas and 14 out of 68 (17%) cell lines. MAGE-C1/CT7 and MAGE-C2/CT10 were both detected in 40% of melanoma metastases. Patients with MAGE-C1/CT7 or MAGE-C2/CT10 positive primary melanoma had significantly more lymph node metastases (p = 0.005 and p<0.001, resp.). Prediction of lymph node metastasis by MAGE-C1/CT7 and MAGE-C2/CT10 was independent of tumor cell proliferation rate (Ki67 labeling index) in a multivariate analysis (p = 0.01). Our results suggest that the expression of MAGE-C1/CT7 and MAGE-C2/CT10 in primary melanoma is a potent predictor of sentinel lymph node metastasis

Persistent Gastric Colonization with Burkholderia pseudomallei and Dissemination from the Gastrointestinal Tract following Mucosal Inoculation of Mice

Melioidosis is a disease of humans caused by opportunistic infection with the soil and water bacterium Burkholderia pseudomallei. Melioidosis can manifest as an acute, overwhelming infection or as a chronic, recurrent infection. At present, it is not clear where B. pseudomallei resides in the mammalian host during the chronic, recurrent phase of infection. To address this question, we developed a mouse low-dose mucosal challenge model of chronic B. pseudomallei infection and investigated sites of bacterial persistence over 60 days. Sensitive culture techniques and selective media were used to quantitate bacterial burden in major organs, including the gastrointestinal (GI) tract. We found that the GI tract was the primary site of bacterial persistence during the chronic infection phase, and was the only site from which the organism could be consistently cultured during a 60-day infection period. The organism could be repeatedly recovered from all levels of the GI tract, and chronic infection was accompanied by sustained low-level fecal shedding. The stomach was identified as the primary site of GI colonization as determined by fluorescent in situ hybridization. Organisms in the stomach were associated with the gastric mucosal surface, and the propensity to colonize the gastric mucosa was observed with 4 different B. pseudomallei isolates. In contrast, B. pseudomallei organisms were present at low numbers within luminal contents in the small and large intestine and cecum relative to the stomach. Notably, inflammatory lesions were not detected in any GI tissue examined in chronically-infected mice. Only low-dose oral or intranasal inoculation led to GI colonization and development of chronic infection of the spleen and liver. Thus, we concluded that in a mouse model of melioidosis B. pseudomallei preferentially colonizes the stomach following oral inoculation, and that the chronically colonized GI tract likely serves as a reservoir for dissemination of infection to extra-intestinal sites

Symptoms of Anxiety and Cardiac Hospitalizations at 12 Months in Patients with Heart Failure

OBJECTIVE: Heart failure (HF) is a leading cause of hospitalization. Clinical and socio-demographic factors have been associated with cardiac admissions, but little is known about the role of anxiety. We examined whether symptoms of anxiety were associated with cardiac hospitalizations at 12 months in HF patients. METHODS: HF outpatients (N=237) completed the Hospital Anxiety and Depression Scale (HADS) at baseline (i.e., inclusion into the study). A cutoff ≥8 was used to indicate probable clinical levels of anxiety and depression. At 12 months, a medical chart abstraction was performed to obtain information on cardiac hospitalizations. RESULTS: The prevalence of symptoms of anxiety was 24.9 % (59/237), and 27.0 % (64/237) of patients were admitted for cardiac reasons at least once during the 12-month follow-up period. Symptoms of anxiety were neither significantly associated with cardiac hospitalizations in univariable logistic analysis [OR=1.13, 95% CI (0.59–2.17), p=0.72] nor in multivariable analysi

Anticipating implementation of colorectal cancer screening in The Netherlands: a nation wide survey on endoscopic supply and demand

<p>Abstract</p> <p>Background</p> <p>Colorectal cancer (CRC) screening requires sufficient endoscopic resources. The present study aims to determine the Dutch endoscopic production and manpower for 2009, evaluate trends since 2004, determine additional workload which would be caused by implementation of a CRC screening program, and inventory colonoscopy rates performed in other European countries.</p> <p>Methods</p> <p>All Dutch endoscopy units (N = 101) were surveyed for manpower and the numbers of endoscopy procedures performed in 2009. Based on calculations in the report issued by the Dutch Health Council, future additional workload caused by faecal immunochemical test (FIT) screening was estimated. The number of colonoscopies performed in Europe was evaluated by a literature search and an email-inquiry.</p> <p>Results</p> <p>Compared to 2004, there was a 24% increase in total endoscopies (N = 505,226 in 2009), and a 64% increase in colonoscopies (N = 191,339 in 2009) in The Netherlands. The number of endoscopists had increased by 4.6% (N = 583 in 2009). Five years after stepwise implementation of FIT-based CRC screening, endoscopic capacity needs to be increased an additional 15%. A lack of published data on the number of endoscopies performed in Europe was found. Based on our email-inquiry, the number of colonoscopies per 100,000 inhabitants ranged from 126 to 3,031 in 15 European countries.</p> <p>Conclusions</p> <p>Over the last years, endoscopic procedures increased markedly in The Netherlands without a corresponding increase in manpower. A FIT-based CRC screening program requires an estimated additional 15% increase in endoscopic procedures. It is very likely that current colonoscopy density varies widely across European countries.</p