STUDIES CONCERNING THE SITE OF RENIN FORMATION IN THE KIDNEY : I. THE ABSENCE OF RENIN IN THE AGLOMERULAR KIDNEY OF THE MIDSHIPMAN FISH

1. The absence of glomeruli in the kidney of the midshipman fish (Porichthys notatus) is reported. 2. The detection of renin in the glomerular kidney of the carp, the catfish, and the hog, and the apparent absence of this substance in the aglomerular kidney of the midshipman fish suggest that the tubular portion of the mammalian kidney does not produce or store renin.

The effect of periodontal therapy on serum TNF-alpha and HbA1c levels in type 2 diabetic patients

BACKGROUND

To determine the effect of non-surgical periodontal therapy on serum TNF-alpha and HbA1c levels in poorly and well-controlled type 2 diabetic patients.

METHODS

In total, 45 patients were enrolled in the study; 30 patients with type 2 diabetes mellitus with periodontitis (15 with poorly controlled diabetes, HbA1c >or= 7%, group 1A and 15 with well-controlled diabetes, HbA1c < 7%, group 1B) and 15 patients that were systemically healthy with periodontitis (group 2). The plaque index, gingival index, probing depth, clinical attachment loss, gingival bleeding index, HbA1c value, and circulating TNF-alpha concentration were measured at baseline and three months after the non-surgical periodontal therapy.

RESULTS

All periodontal parameters and serum TNF-alpha levels were significantly decreased three months after the non-surgical periodontal therapy compared to the baseline values in all groups. The HbA1c values were significantly decreased only in well-controlled diabetic patients. We found no significant differences in the periodontal parameters or TNF-alpha levels at baseline and after three months between the two groups.

CONCLUSIONS

Although non-surgical periodontal therapy eliminates local/systemic infection and inflammation via decreases in TNF-alpha, it is insufficient for significantly reducing HbA1c levels without strict glycaemic control in poorly controlled diabetic patients in a short time period.

Budesonide/formoterol maintenance and reliever therapy: impact on airway inflammation in asthma

The aim of the present study was to compare the effectiveness, safety and health economics of budesonide/formoterol maintenance and a novel reliever therapy with conventional best practice in patients with persistent asthma in Canada. After 2 weeks of usual therapy, 1,538 patients were randomised for 6 months to open-label budesonide/formoterol maintenance and reliever therapy 160/4.5 microg twice daily and as needed, or to guideline-based conventional best practice. Severe asthma exacerbations, reliever medication use and total inhaled corticosteroid dose were analysed in all patients and airway inflammation was assessed in a sub-study of 115 patients. No differences were seen in time to first severe exacerbation and severe asthma exacerbation rate. There were numerically fewer emergency room visits or hospitalisations with budesonide/formoterol maintenance and reliever therapy (4.4 versus 7.5 events per 100 patients x yr(-1), 41% reduction); however, this did not reach statistical significance. Mean total inhaled corticosteroid dose, reliever use, asthma medication costs and total annual costs per patient were all significantly lower with budesonide/formoterol maintenance and reliever therapy. Mean sputum eosinophil cell counts remained in the range for controlled inflammation in both groups. In conclusion, budesonide/formoterol maintenance and reliever therapy achieved similar or improved clinical control compared with conventional best practice, with significantly lower total inhaled corticosteroid dose and lower cost, while maintaining similar control of eosinophilic inflammation.

Impact of a spirometry expert system on general practitioners' decision making

The present study assessed the impact of computerised spirometry interpretation expert support on the diagnostic achievements of general practitioners (GPs), and on GPs' decision making in diagnosing chronic respiratory disease. A cluster-randomised controlled trial was performed in 78 GPs who each completed 10 standardised paper case descriptions. Intervention consisted of support for GPs' spirometry interpretation either by an expert system (expert support group) or by sham information (control group). Agreement of GPs' diagnoses was compared with an expert panel judgement, which served as the primary outcome. Secondary outcomes were: additional diagnostic test rates; width of differential diagnosis; certainty of diagnosis; estimated severity of disease; referral rate; and medication or nonmedication changes. Effects were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). There were no differences between the expert support and control groups in the agreement between GPs and expert panel diagnosis of chronic obstructive pulmonary disease (OR (95% CI) 1.08 (0.70-1.66)), asthma (1.13 (0.70-1.80)), and absence of respiratory disease (1.32 (0.61-2.86)). A higher rate of additional diagnostic tests was observed in the expert support group (2.5 (1.17-5.35)). Computerised spirometry expert support had no detectable benefit on general practitioners' diagnostic achievements and the decision-making process when diagnosing chronic respiratory disease.

Obstructive sleep apnoea, cigarette smoking and serum testosterone levels in a male sleep clinic cohort

This study evaluated the impact of obstructive sleep apnoea (OSA) and smoking on total serum testosterone levels in 96 men (mean age 43.3 years; range 25 - 60 years) attending a sleep clinic. Fifty-five men (57.3%) had OSA, defined as an apnoea-hypopnoea index of > or = 15 events/h, recorded during overnight polysomnography, and 42 (43.8%) were current smokers. Mean serum total testosterone levels were significantly lower in OSA subjects (3.4 ng/ml) than in non-OSA subjects (3.9 ng/ml), whereas no significant difference was observed between current smokers and nonsmokers. In a multiple linear regression analysis, serum testosterone was negatively correlated with body mass index and the apnoea-hypopnoea index, but not with age and pack-years of smoking. Our results support previous observations regarding testosterone levels in men with OSA, but, contrary to some earlier reports, there was no positive relationship between smoking and total testosterone in the present cohort.

Replacement of hystological findings: serum hyaluronic acid for fibrosis, high-sensitive C-reactive protein for necroinflamation in chronic viral hepatitis

Because of limitations in biopsy procedure, several non-invasive tests have been developed for predicting the histological findings in chronic hepatitis. A fibrosis (F) score 1 or above and necroinflammation [histological activity index (HAI)] score 4 or above are required to initiate the treatment in chronic viral hepatitis. Literature includes many studies on hyaluronic acid (HA) as a non-invasive procedure in predicting histological findings but lacks on high-sensitive-C-reactive protein (hsCRP). We evaluated the diagnostic value of HA and hsCRP in patients with chronic viral hepatitis. Ninety-eight subjects (42 chronic viral hepatitis, 28 cirrhosis and 28 healthy controls) were included in the study. Liver biopsies were performed on 42 chronic hepatitis patients and assessed by Ishak scoring system. All sera were stored at -70 degrees C until assay. Many laboratory parameters related to viral hepatitis, HA and hsCRP were studied following the instructions. We tried to determine a cut-off value for HA to represent > or =F1 score and that for hsCRP to represent > or =4 HAI score. Hepatitis B virus was the predominant aetiology of chronic hepatitis in our study. Mean HA levels were 113, 754 and 24 ng/ml in patients with chronic hepatitis, cirrhosis and controls, respectively (anova, p < 0.001). A HA level >64.7 ng/ml had a 100% specificity for diagnosing chronic hepatitis. A value > or =154 ng/ml had a 100% specificity, 100% positive predictive value and 90% negative predictive value for diagnosing liver cirrhosis (Area 1.00; p < 0.0001). A cut-off value of 63 ng/ml for HA had a 100% specificity for diagnosing fibrosis score > or =1 in chronic hepatitis (Area 0.86; p < 0.001). An hsCRP level >0.56 mg/dl had a 100% specificity and 12% sensitivity for diagnosing chronic hepatitis (Area 0.71; p = 0.002), while cut-off of 0.53 mg/dl had 75% specificity for diagnosing HAI > or = 4 in chronic hepatitis (Area 0.32; p = 0.132). This study supported the HA level in predicting fibrosis score > or =1 with a cut-off value of 63 ng/ml. Cut-off of 154 ng/ml had a strong worth for cirrhosis. A cut-off of hsCRP for predicting HAI score > or =4 warrants further evaluation in wider study populations. We concluded that we are a bit closer to the strategy for guiding therapy in patients with chronic hepatitis, without a liver biopsy.

SmartCell, a framework to simulate cellular processes that combines stochastic approximation with diffusion and localisation: analysis of simple networks

SmartCell has been developed to be a general framework for modelling and simulation of diffusion-reaction networks in a whole-cell context. It supports localisation and diffusion by using a mesoscopic stochastic reaction model. The SmartCell package can handle any cell geometry, considers different cell compartments, allows localisation of species, supports DNA transcription and translation, membrane diffusion and multistep reactions, as well as cell growth. Moreover, different temporal and spatial constraints can be applied to the model. A GUI interface that facilitates model making is also available. In this work we discuss limitations and advantages arising from the approach used in SmartCell and determine the impact of localisation on the behaviour of simple well-defined networks, previously analysed with differential equations. Our results show that this factor might play an important role in the response of networks and cannot be neglected in cell simulations.

Decay of quantum correlations in atom optics billiards with chaotic and mixed dynamics

We perform echo spectroscopy on ultracold atoms in atom-optics billiards to study their quantum dynamics. The detuning of the trapping laser is used to change the "perturbation", which causes a decay in the echo coherence. Two different regimes are observed: first, a perturbative regime in which the decay of echo coherence is nonmonotonic and partial revivals of coherence are observed in contrast with the predictions of random matrix theory. These revivals are more pronounced in traps with mixed dynamics as compared to traps where the dynamics is fully chaotic. Next, for stronger perturbations, the decay becomes monotonic and independent of the strength of the perturbation. In this regime no clear distinction can be made between chaotic traps and traps with mixed dynamics.

Amyloid precursor protein regulates differentiation of human neural stem cells

Although amyloid beta (Abeta) deposition has been a hallmark of Alzheimer's disease (AD), the absence of a phenotype in the beta amyloid precursor protein (APP) knockout mouse, tends to detract our attention away from the physiological functions of APP. Although much attention has been focused on the neurotoxicity of Abeta, many studies suggest the involvement of APP in neuroplasticity. We found that secreted amyloid precursor protein (sAPP) increased the differentiation of human neural stem cells (hNSCs) in vitro, while an antibody-recognizing APP dose-dependently inhibited these activities. With a high dose of sAPP treatment or wild-type APP gene transfection, hNSCs were differentiated into astrocytes rather than neurons. In vivo, hNSCs transplanted into APP-transgenic mouse brain exhibited glial differentiation rather than neural differentiation. Our results suggest that APP regulates neural stem cell biology in the adult brain, and that altered APP metabolism in Down syndrome or AD may have implications for the pathophysiology of these diseases.