Cone dystrophy and ectopic synaptogenesis in a Cacna1f loss of function model of congenital stationary night blindness (CSNB2A).

Congenital stationary night blindness 2A (CSNB2A) is an X-linked retinal disorder, characterized by phenotypically variable signs and symptoms of impaired vision. CSNB2A is due to mutations in CACNA1F, which codes for the pore-forming α1F subunit of a L-type voltage-gated calcium channel, Cav1.4. Mouse models of CSNB2A, used for characterizing the effects of various Cacna1f mutations, have revealed greater severity of defects than in human CSNB2A. Specifically, Cacna1f-knockout mice show an apparent lack of visual function, gradual retinal degeneration, and disruption of photoreceptor synaptic terminals. Several reports have also noted cone-specific disruptions, including axonal abnormalities, dystrophy, and cell death. We have explored further the involvement of cones in our 'G305X' mouse model of CSNB2A, which has a premature truncation, loss-of-function mutation in Cacna1f. We show that the expression of genes for several phototransduction-related cone markers is down-regulated, while that of several cellular stress- and damage-related markers is up-regulated; and that cone photoreceptor structure and photopic visual function - measured by immunohistochemistry, optokinetic response and electroretinography - deteriorate progressively with age. We also find that dystrophic cone axons establish synapse-like contacts with rod bipolar cell dendrites, which they normally do not contact in wild-type retinas - ectopically, among rod cell bodies in the outer nuclear layer. These data support a role for Cav1.4 in cone synaptic development, cell viability, and synaptic transmission of cone-dependent visual signals. Although our novel finding of cone-to-rod-bipolar cell contacts in this mouse model of a retinal channelopathy may challenge current views of the role of Cav1.4 in photopic vision, it also suggests a potential new target for restorative therapy.

An evaluation of the performance of the soil temperature simulation algorithms used in the PRZM model.

Soil temperature simulation is an important component in environmental modeling since it is involved in several aspects of pollutant transport and fate. This paper deals with the performance of the soil temperature simulation algorithms of the well-known environmental model PRZM. Model results are compared and evaluated based on the basis of its ability to predict in situ measured soil temperature profiles in an experimental plot during a 3-year monitoring study. The evaluation of the performance is based on linear regression statistics and typical model statistical errors such as the root mean square error (RMSE) and the normalized objective function (NOF). Results show that the model required minimal calibration to match the observed response of the system. Values of the determination coefficient R(2) were found to be in all cases around the value of 0.98 indicating a very good agreement between measured and simulated data. Values of the RMSE were found to be in the range of 1.2 to 1.4 degrees C, 1.1 to 1.4 degrees C, 0.9 to 1.1 degrees C, and 0.8 to 1.1 degrees C, for the examined 2, 5, 10 and 20 cm soil depths, respectively. Sensitivity analyses were also performed to investigate the influence of various factors involved in the energy balance equation at the ground surface on the soil temperature profiles. The results showed that the model was able to represent important processes affecting the soil temperature regime such as the combined effect of the heat transfer by convection between the ground surface and the atmosphere and the latent heat flux due to soil water evaporation.

Can high resolution computed tomography predict lung function in patients with chronic obstructive pulmonary disease?

High-resolution computed tomography (HRCT) is a useful method for quantifying the extent of emphysema. Few reports have mentioned the relationships between HRCT scans and pulmonary function tests in chronic obstructive pulmonary disease (COPD). For diagnosis, COPD requires chronic airflow limitation and emphysema and/or chronic bronchitis. We examined 20 who were previous smokers with middle to moderate COPD. All were normocapnic with mean arterial oxygen pressure (PaO2) 77,52 +/- 16,789 mmHg. Forced spirometry, somatic plethysmography and cardiopulmonary exercise test were performed in each patient. HRCT was performed in both full inspiration and full expiration at three levels through the upper (at the aortic arch), lower (2 cm above the diaphragm), and middle lung (midpoint between upper and lower) levels. During expiration all pulmonary function parameters correlated with the HRCT grade in the middle right and left part of the lungs. The middle right part of the lung during expiration correlated statistically significant with MVV (r = -0.681, p = 0.001), forced vital capacity (FVC) (r = -0.477, p = 0.027), forced expiratory volumein 1 sec (FEV1) (r = -0.632, p = 0.002), resistance (r = 0.674, p = 0.001), residual volume (RV) (r = 0.733, p = 0.001), total lung capacity (TLC) (r = 0.696, p = 0.001), functional residual capacity (FRC) (r = 0.752, p = 0.001) and peak oxygen consumption during exercise (VO2) (r = -0.493, p = 0.023). The middle left part of the lung during expiration correlated statistically significant with MVV (r = -0.673, p = 0.001), FVC (r = -0.493, p = 0.027), FEV1 (r = -0.629, p = 0.003), resistance (r = 0.593,p = 0.005), RV (r = 0.601, p = 0.005), TLC (r = 0.546, p = 0.012), FRC (r = 0.594, p = 0.006) and peak VO2 (r = -0.525, p = 0.015). Forced expiratory volume in 1 sec (FEV1), which is a well-established measure of airflow obstruction, correlated with the HRCT grade (1) in the middle left part of the lung during inspiration (r = -0.468, p = 0.035) and during expiration (r = - 0.629, p = 0.003) (2) in the lower right lung during inspiration (r = -0.567, p = 0.007) and during expiration (r = -0.558, p = 0.008) (3) in the lower left lung during inspiration (r = -0.542, p = 0.011) and during expiration (r = -0.558, p = 0.008) (4) in the upper right lung during expiration (r = -0.469, p = 0.037) (5) in the upper left lung during expiration (r = -0.463, p = 0.035) and (6) in the middle right lung during expiration (r = -0.632, p = 0.002). According to our results HRCT was a valuable tool for evaluating the severity of COPD--especially the middle right and left part of the lungs, during expiration--and correlated well with pulmonary function tests.

Asymptomatic adult cystic lymphangioma of the spleen: case report and review of the literature.

In the present report we describe a case of an asymptomatic splenic cystic lymphangioma in a 43 year-old female. Only a few cases of this benign tumor have been reported in adult patients so far. Clinical examination revealed a tender mass in the upper left quadrant of the abdomen. Abdominal ultrasound and CT-scan revealed a large well-defined splenic cystic mass surrounded by multiple peripheral cysts, all divided by thin septa. MRI confirmed these findings and excluded the possibility of malignant degeneration. Histologic examination permitted the accurate diagnosis to be made. Different imaging findings of this tumor have been described but only a few reports have focused on the value of MRI imaging.

Artificial neural networks as a classification method in the behavioural sciences.

The classification and recognition of individual characteristics and behaviours constitute a preliminary step and is an important objective in the behavioural sciences. Current statistical methods do not always give satisfactory results. To improve performance in this area, we present a methodology based on one of the principles of artificial neural networks: the backpropagation gradient. After summarizing the theoretical construction of the model, we describe how to parameterize a neural network using the example of the individual recognition of vocalizations of four fallow deer (Dama dama). With 100% recognition and 90% prediction success, the results are very promising.

Fibrin glue for sealing the needle track in fine-needle percutaneous lung biopsy using a coaxial system: Part II--Clinical study.

PURPOSE: Following percutaneous lung biopsy (PLB), we used fibrin glue as a sealant in 26 patients for the purpose of decreasing the incidence of pneumothorax. METHODS: All 26 patients (group A) had chronic obstructive pulmonary disease (COPD). The results for group A were compared with a control group of 32 patients (group B), also with COPD and in whom fibrin glue was not used. All biopsies were conducted under computed tomography (CT) using a coaxial needle system consisting of 19-gauge and 22-gauge needles. RESULTS: Pneumothorax developed in five patients (19.2%) in group A and in one instance, drainage was required (3.8%). In group B, pneumothorax developed in 13 patients (40.6%) and in six instances (18.8%) drainage was required. Comparing the use of chest-tube drainage in the two groups, a statistical significance was observed, p < 0.0025). No adverse reactions related to the fibrin glue were observed. CONCLUSION: Our results indicate that fibrin glue is a safe sealing material for lung PLB and serves to decrease the incidence and, in particular, the severity of pneumothorax, especially in high-risk patients.

[The use of homologous coagulated blood for prevention of pneumothorax following percutaneous lung biopsy (experimental study)]. / Die Verwendung von homologem, geronnenem Blut zur Pneumothoraxprophylaxe nach perkutaner Lungenbiopsie (experimentelle Studie).

We performed 52 percutaneous lung biopsies on 34 animals (NZ rabbits) using a coaxial needle system. In 19 animals we introduced homologous clotted blood through the outer plastic cannula in order to prevent a pneumothorax. CT was used to demonstrate the pneumothorax. The aim of the experiment was to see whether clotted blood would reduce the incidence of pneumothoraces. In addition we wanted to determine the complications of this method. We found that, correctly used, clotted blood significantly reduced the incidence of pneumothoraces (31.57% as against 64.70% in the control group). It also reduced the extent of the pneumothorax. The method has no complications.

[MRT of the status following augmentation plasty of the anterior cruciate ligament using carbon fibers]. / MRT bei Zustand nach Augmentationsplastiken am vorderen Kreuzband mit Kohlenstoffasern.

In 19 patients treated with carbon-fiber ligament augmentation for the anterior cruciate ligament, the clinical findings were compared via MRI. Visualization of the intra- and extra-articular portion of the graft was possible in 84%. The integrity of the ligaments was be shown in an equal percentage. Thus, MRI is a useful diagnostic tool for non-invasive imaging for repeated follow-ups in patients with carbon-fiber ligament augmentation.

Is natural infection with M. tuberculosis protective against cancer?

In order to investigate the effect of natural infection with M. tuberculosis on cancer incidence, a case-control study was undertaken on 108 recently diagnosed cancer cases (all sites) and 317 controls. After removal of cancer cases or controls considered immunoincompetent (25% and 17% respectively), the remaining subjects were tested by intradermal injection of tuberculin (5 I.U.). Results were compared separately for each sex. It was observed that the proportion of tuberculin-negative subjects was higher in cancer patients than in controls within each sex (males 31.3% vs 20.1%, females: 59.2% vs 37.3%) the difference in females being statistically significant (p less than 0.02). Odds ratio for negative tuberculin test was 1.80 and 2.44 for males and females respectively. The results are discussed on the basis of cell-mediated immunity produced by infection with M. tuberculosis and its relations with tumor growth.

Sensitivity of two-dimensional echocardiography in the direct visualization of atrial septal defect utilizing the subcostal approach: experience with 154 patients.

In the standard precordial echocardiographic imaging planes, there is frequent dropout of atrial septal echoes in the region of the fossa ovalis that can be minimized by use of the subcostal imaging approach. The diagnostic sensitivity of this approach was reviewed in 154 patients (mean age 31 years, range 2 months to 74 years) with documented atrial septal defect in whom a satisfactory image of the atrial septum could be obtained. Subcostal two-dimensional echocardiography successfully visualized 93 (89%) of the 105 ostium secundum atrial septal defects, all 32 (100%) ostium primum defects and 7 (44%) of the 16 sinus venosus defects. A defect was not visualized (false negative response) in 12 patients (11%) with an ostium secundum defect and in 9 patients (56%) with a sinus venosus defect. In three of the former and five of the latter, a two-dimensional echocardiographic contrast examination established the presence of the interatrial shunt. Twenty-four patients (16%) with clinical findings of uncomplicated atrial septal defect confirmed by two-dimensional echocardiography underwent surgical repair of the defect without preoperative cardiac catheterization. There were no perioperative complications. Two-dimensional echocardiographic examination of the atrial septum utilizing the subcostal approach is the preferred method for the confident, noninvasive diagnosis and categorization of atrial septal defects. Two-dimensional echocardiographic contrast and Doppler examinations complement the technique and enhance diagnostic accuracy.