Metabolism of the oestrogens and their conjugates

Optimal conditions for hydrolysis of urinary oestrogen conjugates in the human have been sought, A Β-glucuronidasesulphatase mixture (H, plmatia) is shown to be effective in cleaving the sulphate and glucosiduronate forms of some eight metabolites, A bacterial (E, coli) Β-glucuronidase preparation is particularly active in hydrolysing both oestrogen and 17- ketosteroid glucosiduronates. Using these techniques and other improved methodology, levels of seven or eight oestrogen metabolites have been measured in normal and diabetic pregnancy (human). Apparent abnormalities are seen in the diabetic state and tentative conclusions are drawn regarding sites of production of certain oestrogens during pregnancy.Metabolism of some free oestrogens have been studied in the human in vivo and in vitro and in certain other species in vitro. Oestriol and 16-epioestriol are shown to be not necessarily 'end products' of metabolism but to be variably metabolized by laying hen liver, erythrocytes of certain species and by the human in vivo. The 2-methoxylation of oestrone has been studied in rat liver fractions and the metabolism of the clinically useful synthetic compound 17α(-ethynyloestradiol-17Β-3-cyclopentyl ether has been delineated in the human.The conjugation patterns of urinary oestrogen metabolites in the pregnant and non-pregnant human are shown to be similar by a differential hydrolytic technique. The quantitative importance of oestrone in the sulphate fraction has been established as well as that of 16α-hydroxyoestrone and 16-ketooestradiol-17Β in the sulphoglucosiduronate fraction.It has been shown that tissues from the laying hen are more active, with respect to aulphurylation, towards phenolic steroids than to dehydroisoandrostarone. Also, liver from the same species directly interconverts the 3~sulphates of oestrone and 17Β-oestradiol. The ability of a rat liver preparation to sulphurylate the 3 position of phenolic steroids appears to be related to the constituents of ring D of the steroid.The glucosiduronates and sulphates of oestrone and 17Β-oestradiol have been successfully separated chromatographically and the procedure has been employed to prove that the human conjugates 17Β-oestradiol to yield both its 3- and 17-monoglucosiduronates. The fates of the latter two conjugates differ in vivo in that the former is subjected mainly to 17-dehydrogenation and little deconjugation, whereas the latter undergoes an enterohepatic type of metabolism with considerable deconjugation and reconjugation. The metabolism of the monoglucosides of 17Β-oestradiol in the human has been studied. The 3-glucoside residue is rapidly removed with the release, and extensive metabolism, of 17Β-oestradiol. The 17-glucoside residua is much less readily removed and the metabolism of the 17-glucosides of 17Β-oestradiol and 17α-oestradiol shows some resemblance to that of 17Β-oestradiol-17-glucosiduronate

Domestication constrains the ability of dogs to convey emotions via facial expressions in comparison to their wolf ancestors

Dogs (Canis lupus familiaris) are the domestically bred descendant of wolves (Canis lupus). However, selective breeding has profoundly altered facial morphologies of dogs compared to their wolf ancestors. We demonstrate that these morphological differences limit the abilities of dogs to successfully produce the same affective facial expressions as wolves. We decoded facial movements of captive wolves during social interactions involving nine separate affective states. We used linear discriminant analyses to predict affective states based on combinations of facial movements. The resulting confusion matrix demonstrates that specific combinations of facial movements predict nine distinct affective states in wolves; the first assessment of this many affective facial expressions in wolves. However, comparative analyses with kennelled rescue dogs revealed reduced ability to predict affective states. Critically, there was a very low predictive power for specific affective states, with confusion occurring between negative and positive states, such as Friendly and Fear. We show that the varying facial morphologies of dogs (specifically non-wolf-like morphologies) limit their ability to produce the same range of affective facial expressions as wolves. Confusion among positive and negative states could be detrimental to human–dog interactions, although our analyses also suggest dogs likely use vocalisations to compensate for limitations in facial communication

3-Year prospective multicenter study on one-stage implant surgery and early loading in the edentulous mandible

Background: The long-term success rates achieved in dental implantology suggest that flexibility might well exist within the various implant systems to a degree that an altered protocol (ie, one-stage surgery and immediate or early loading) can be performed under controlled conditions. However, before variations of the protocol can be considered for general use, they must be subjected to critical analysis, particularly with respect to the predictability of osseointegration, alteration of soft tissue barrier, and relative change in bone height around the implants. Purpose: The aim of this prospective multicenter study was to evaluate implant survival and periimplant conditions around endosseous implants placed in a one-stage surgical procedure and early loading. Materials and Methods: A total of 170 implants were placed in 40 patients with mandibular edentulism and were functionally loaded within 6 weeks with overdentures (n = 30) or fixed prostheses (n = 10). All patients and prosthetic constructions were evaluated according to a standardized protocol during 3 years of follow-up. Cumulative implant survival rates were calculated, and implant loss in relation to implant size and bone quality and quantity were evaluated. Furthermore, the protocol included assessment of clinical (plaque and bleeding scores, prosthesis stability) and radiographic parameters. Results: Over a period of 3 years, the implant survival rate was 93% for both implants and prostheses (fixed or removable). No implants were lost after the first year of loading. The periimplant tissues were in a healthy condition. Mean marginal bone resorption from the time of loading to the 3-year follow-up was 0.41 mm (SD 0.52). Conclusions: From this study it may be concluded that early loading results in good implant survival and proper periimplant health in edentulous mandibles.</p

Complication rates and patient satisfaction with removable dentures

PURPOSE. The purpose of this clinical study was to evaluate the frequency and type of prosthetic complications in relation to type and properties of removable dentures and to investigate the influence of these complications and several data about the existing dentures on patient satisfaction. MATERIALS AND METHODS. Ninety nine patients (44 males and 55 females) wearing removable dentures have been included in the study. The complications of the patients were recorded; patient satisfaction was determined with a Visual Analog Scale (VAS) and the relationship of complications and patient satisfaction with several data about the dentures such as denture age, type of denture, centric relation and vertical dimension was investigated. Kruskal Wallis, Mann Whitney U and Chi square tests were used for statistical analyses. The results were evaluated statistically at a significance level of P<.05. RESULTS. Need for addition of artificial teeth for dentures with correct centric relations was found to be significantly lower than dentures with wrong centric relations (P<.01). Loss of retention, ulcerations and high vertical dimension affected the VAS chewing ability scores negatively and ulcerations affected the VAS phonation scores negatively (P<.05). CONCLUSION. Considering the results of this study, it can be concluded that loss of retention, ulcerations and high vertical dimension caused patient dissatisfaction. Additionally, dentures with wrong centric relations caused need for addition of artificial teeth. [J Adv Prosthodont 2012;4:109-15

Development of a human model for the study of effects of hypoxia, exercise, and sildenafil on cardiac and vascular function in chronic heart failure

Background: Pulmonary hypertension is associated with poor outcome in patients with chronic heart failure (CHF) and may be a therapeutic target. Our aims were to develop a noninvasive model for studying pulmonary vasoreactivity in CHF and characterize sildenafil's acute cardiovascular effects. Methods and Results: In a crossover study, 18 patients with CHF participated 4 times [sildenafil (2 × 20 mg)/or placebo (double-blind) while breathing air or 15% oxygen] at rest and during exercise. Oxygen saturation (SaO2) and systemic vascular resistance were recorded. Left and right ventricular (RV) function and transtricuspid systolic pressure gradient (RVTG) were measured echocardiographically. At rest, hypoxia caused SaO2 (P = 0.001) to fall and RVTG to rise (5 ± 4 mm Hg; P = 0.001). Sildenafil reduced SaO2 (−1 ± 2%; P = 0.043), systemic vascular resistance (−87 ± 156 dyn·s−1·cm−2; P = 0.034), and RVTG (−2 ± 5 mm Hg; P = 0.05). Exercise caused cardiac output (2.1 ± 1.8 L/min; P &lt; 0.001) and RVTG (19 ± 11 mm Hg; P &lt; 0.0001) to rise. The reduction in RVTG with sildenafil was not attenuated by hypoxia. The rise in RVTG with exercise was not substantially reduced by sildenafil. Conclusions: Sildenafil reduces SaO2 at rest while breathing air, this was not exacerbated by hypoxia, suggesting increased ventilation–perfusion mismatching due to pulmonary vasodilation in poorly ventilated lung regions. Sildenafil reduces RVTG at rest and prevents increases caused by hypoxia but not by exercise. This study shows the usefulness of this model to evaluate new therapeutics in pulmonary hypertension