Select types of supporting cell in the inner ear express aquaporin-4 water channel protein

Aquaporins (AQPs) confer a high water permeability on cell membranes and play important parts in secretory and absorptive epithelia in kidney and other organs. Here we investigate whether AQPs are expressed in the sensory epithelia of the inner ear, where a precise volume regulation is crucial. By use of specific antibodies it was found that the inner ear contains AQP1 and 4 while being devoid of detectable levels of AQP2, 3 or 5. Immunofluorescence and postembedding immunogold labelling revealed a strictly non-epithelial distribution of AQP1, confirming previous data. In contrast, AQP4 protein and mRNA (visualized by in situ hybridization) were concentrated in select types of supporting cell, including Hensen's cells and inner sulcus cells. Immunogold particles signalling AQP4 were confined to the basolateral plasma membrane of Hensen's cells and to the basal plasma membrane of Claudius cells and inner sulcus cells. AQP4 was also found in supporting cells of the vestibular end organs, but was absent from transitional epithelial cells and dark cells. Strong labelling for AQP4 and AQP4-mRNA was associated with the central part of the cochlear and vestibular nerves. Hair cells were consistently unlabelled. Our findings indicate that AQP4 may facilitate osmotically driven water fluxes in the sensory epithelia of the inner ear and thus contribute to the volume and ion homeostasis at these sites.     

Distribution of glutamine-like immunoreactivity in the cerebellum of rat and baboon (Papio anubis) with reference to the issue of metabolic compartmentation

Summary The cellular and subcellular localization of glutamine, a major glutamate precursor, was studied by means of an antiserum raised against glutaraldehydefixed glutamine. Ultrathin sections from the cerebellar cortex of rat and baboon (Papio anubis) were incubated sequentially in the primary antiserum and in a secondary antibody coupled to colloidal gold particles. The labelling intensity was quantified by computer-aided calculation of gold particle densities. High levels of immunoreactivity occurred in glial cells (Bergmann fibres, astrocytes, and oligodendrocytes), intermediate levels in cell bodies and processes of granule cells, and low levels in terminals of presumed GABAergic or glutamatergic fibres (terminals of basket and Golgi cells, and of parallel, mossy, and climbing fibres). The labelling intensity of Purkinje cells showed some variation, but never exceeded that in glial cells. Within the nerve fibre terminals, the glutamine-like immunoreactivity showed some preference for mitochondria, but was otherwise evenly distributed. The predominant glial localization of glutamine was also obvious in light microscopic preparations processed according to the postembedding peroxidase-antiperoxidase procedure. Gold particle densities over different types of profile in glutamine immunolabelled sections were compared with particle densities over the corresponding types of profiles in neighbouring sections labelled with an antiserum to glutaraldehyde-fixed glutamate. The glutamate/glutamine ratio, expressed arbitrarily by the ratio between the respective gold particle densities, varied by a factor of about 6, with the highest ratio in the putative glutamatergic mossy and parallel fibre terminals, and the lowest ratio in glial elements. The remaining tissue components displayed intermediate ratios. The present study provides direct morphological evidence for the existence in the brain of distinct compartments with differing glutamate/glutamine ratios.This paper is dedicated to Professor Fred Walberg on the occasion of his 70th birthdayOn leave of absence from Department of Anatomy, Capital Institute of Medicine, You An Men Street, Beijing, China     

Quantitative determination of cell surface β-adrenoceptors in different rat skeletal muscles

In the present study, the density of cell surface beta-adrenergic receptors was determined in different skeletal muscles using the hydrophilic ligand [3H]CGP 12177. The density of beta-adrenergic receptors was highest in the slow-twitch soleus muscle (32.8+/-0.9 fmol mg dw(-1)) and lowest in the fast-twitch glycolytic white gastrocnemius (10.4+/-0.5 fmol mg dw(-1)) beta-Adrenoceptor density correlated closely with the percentage of type-I fibres (r=0.979; P<0.0001) and inversely with the percentage of type-IIB fibres (r=696; P<0.03). Incubation with isoprenaline (10 microM) for 30 min decreased the density of beta-adrenergic receptors in the cell surface from 32.9+/-0.8 to 19.3+/-0.7 fmol mg dw(-1) in the soleus and from 16.8+/-1.0 to 12.0+/-0.7 fmol mg dw(-1) in the epitrochlearis. Internalisation appeared rapid (half-time less than 5 min). To study externalisation of beta-adrenergic receptors, soleus strips were incubated 30 min with 10 microM isoprenaline and then transferred to buffer without agonist. The first incubation reduced the density to approximately 50%, the subsequent incubation without agonist increased cell surface receptor density to approximately 80% of the initial density after 1 h. No further increase was observed over the next 2 h, suggesting that some of the receptors had been degraded. Insulin or contractile activity did not influence rate of externalisation.     

The genetics of congenital aniridia—a guide for the ophthalmologist

Congenital aniridia is a rare panocular disease caused by fundamental disturbances in the development of the eye, characterized primarily by hypoplasia of the iris and macula. Severe secondary complications such as keratopathy, cataract, and glaucoma are common and often lead to considerable visual impairment or blindness. Many complications in aniridia patients are difficult to treat and present a challenge for the ophthalmologist. Increasingly, associated nonocular features of the disease are also being recognized. Over the past decades, major steps have been made in the understanding of the genetic basis of aniridia. Moreover, recent studies have prepared the ground for future treatment options based on specific mutations. Therefore, specific knowledge about genetics in aniridia has become more important than ever. We provide an overview of the field of aniridia genetics and its clinical implications.     

Clinical significance of the WHO grades of follicular lymphoma in a population-based cohort of 505 patients with long follow-up times

The prognostic value of grading follicular lymphoma has been debated since the 1980s. There is consensus that World Health Organization (WHO) grades 1 and 2 are indolent, but not whether grades 3A or 3B are aggressive. We retrospectively reviewed the follicular lymphoma diagnoses according to the 2008 WHO classification in all diagnostic specimens from a population-based cohort of 505 patients with a median follow-up time of 10·0years (range, 4·6-16·0). After excluding 43 patients with concomitant diffuse large B-cell lymphoma, 345 remained with grade 1-2, 94 with grade 3A, and 23 with grade 3B follicular lymphoma. Grades 1-2 and 3A seemed equally indolent, with indistinguishable clinical courses, even in patients receiving anthracyclines. Compared with grades 1-3A and independently of clinical factors, grade 3B correlated with higher mortality (P=0·008), but outcome was improved after upfront anthracycline-containing therapy (P=0·015). In contrast to grade 1-3A patients, grade 3B patients experienced no relapses or deaths beyond 5years of follow-up. Furthermore, patients with grade 3B were predominantly male and seldom presented with bone-marrow involvement. We conclude that follicular lymphoma grade 1-3A is indolent and incurable with conventional therapy. Grade 3B appears to be an aggressive but curable disease.     

Expression of CD18 (integrin β2 chain) correlates with prognosis in malignant B cell lymphomas

Summary. Several studies have shown that cell cycle related parameters including DNA synthesis and activation antigen expression can predict patient survival in lymphoma patients. In this study of 69 malignant B cell lymphomas we have examined the cell surface expression of several cell interaction and activation molecules by flow cytometry. Expression of CD18 (integrin β₂ chain) was found to correlate strongly with patient survival (median follow up 50 months) even when adjusting for other important prognostic factors ( P = 0.0001). The percentage of cells positive for CDw75 proved important both as a single parameter and in the multivariate analysis. Histology, classified as low versus high grade malignancy, bulky versus not bulky disease and high versus low thymidine incorporation, was also found to correlate with prognosis in this study.     

Change in basic need frustration in relation to perfectionism,anxiety, and performance in elite junior performers

The present study examined whether there were different growth profiles in basic need frustration in elite junior performers over a nine-month period. Subsequently, we examined whether the identified growth profiles differed in their levels of perfectionistic strivings and evaluative concerns measured at baseline and, additionally, whether they were associated with higher or lower levels of anxiety and perceived performance level in the end of the period. A sample of 259 (M_age = 17.31; SD_age = 0.97) elite junior performers from sports and performing arts completed an online questionnaire to report their self-ratings of the study variables. The analyses were conducted using growth mixture modeling in Mplus 8.0. Two main contrasting growth profiles were identified in each of the basic need frustration. Perfectionistic strivings were overall higher than evaluative concerns, but did not differ between the growth profiles. Conversely, evaluative concerns differed significantly between the identified growth profiles. Higher levels of evaluative concerns were associated with the most maladaptive growth profiles. Indeed, elite junior performers, who experienced moderate and increasing levels of competence and autonomy frustration, reported higher levels of anxiety and lower levels of perceived performance level than those who reported low and decreasing levels of competence and autonomy frustration. Based on these findings, evaluative concerns and basic need frustration appear to play key roles in the development of maladaptive motivational processes over time.     

Salmonid alphavirus glycoprotein E2 requires low temperature and E1 for virion formation and induction of protective immunity

Salmonid alphavirus (SAV; also known as Salmon pancreas disease virus; family Togaviridae) causes pancreas disease and sleeping disease in Atlantic salmon and rainbow trout, respectively, and poses a major burden to the aquaculture industry. SAV infection in vivo is temperature-restricted and progeny virus is only produced at low temperatures (10–15 °C). Using engineered SAV replicons we show that viral RNA replication is not temperature-restricted suggesting that the viral structural proteins determine low-temperature dependency. The processing/trafficking of SAV glycoproteins E1 and E2 as a function of temperature was investigated via baculovirus vectors in Sf9 insect cells and by transfection of CHSE-214 fish cells with DNA constructs expressing E1 and E2. We identified SAV E2 as the temperature determinant by demonstrating that membrane trafficking and surface expression of E2 occurs only at low temperature and only in the presence of E1. Finally, a vaccination-challenge model in Atlantic salmon demonstrates the biological significance of our findings and shows that SAV replicon DNA vaccines encoding E2 elicit protective immunity only when E1 is co-expressed. This is the first study that identifies E2 as the critical determinant of SAV low-temperature dependent virion formation and defines the prerequisites for induction of a potent immune response in Atlantic salmon by DNA vaccination.     

Long-Term Improvements in Pulmonary Function 5 Years After Bariatric Surgery

Background

Obesity is associated with reduced pulmonary function. We evaluated pulmonary function and status of asthma and obstructive sleep apnoea syndrome (OSAS) before and 5 years after bariatric surgery.

Methods

Spirometry was performed at baseline and 5 years postoperatively. Information of asthma and OSAS were recorded. Of 113 patients included, 101 had undergone gastric bypass, 10 duodenal switch and 2 sleeve gastrectomy.

Results

Eighty (71 %) patients were women, mean preoperative age was 40 years and preoperative weight was 133 kg in women and 158 kg in men. Five years postoperatively, weight reduction was 31 % (42 kg; p?<?0.001) in women and 24 % (38 kg; p?<?0.001) in men. Forced expiratory volume in 1 s (FEV1) increased 4.1 % (116 ml; p?<?0.001) in women and 6.7 % (238 ml; p?=?0.003) in men. Forced vital capacity (FVC) increased 5.8 % (209 ml; p?<?0.001) in women and 7.6 % (349 ml; p?<?0.001) in men. Gender and weight loss were independently associated with the improvements in FEV1 and FVC. At follow-up, FEV1 had increased 36 % of the difference towards the estimated normal FEV1, and there was a corresponding 70 % recovery of FVC. These improvements occurred despite an expected decline in pulmonary function by age during the study period. Of the asthmatics and OSAS patients, 48 and 80 %, respectively, were without symptoms 5 years postoperatively.

Conclusions

Pulmonary function measured with spirometry was significantly improved 5 years after bariatric surgery, despite an expected age-related decline during this period. Symptoms of asthma and OSAS also improved.