Sleep complaints and their relation with drug treatment in patients suffering from Parkinson's disease.

The aim of this research was to quantify sleep problems in patients suffering from Parkinson's disease by means of the new Parkinson's Disease Sleep Scale (PDSS) and to correlate such problems with the possible influence of current drug treatment. A total of 70 patients (36 men and 34 women) with a diagnosis of Parkinson's disease were enrolled. Their mean age was 69.7 +/- 8.2 years, and duration of disease was 7.4 +/- 4.8 years. All patients completed the PDSS and the Unified Parkinson's Disease Rating Scale (UPDRS Parts I-IV). Drug consumption and doses were registered. The mean score on the PDSS scale was 109.23 +/- 19.75 and on the UPDRS III scale was 25.24 +/- 11.35. The lowest scores were obtained in Item 3 (sleep fragmentation): 5.53 (2.46); and in Item 8 (nocturia): 5.75 (2.91). There was a weak correlation between the PDSS and UPDRS III (cc = -0.355, P = 0.003), PDSS and UPDRS I (cc = -0.272, P = 0.02), and PDSS and UPDRS IV (cc = -0.416, P < 0.001). Motor conditions, mental state, and drug complications influence sleep quality. Although this effect was significant, it was not of a great magnitude. Dopaminergic drugs did not increase daytime sleepiness. As a whole, sleep quality in patients who took dopaminergic agonists did not differ from that of patients who took levodopa in monotherapy.     

A preventive intervention for enhancing resilience among highly stressed urban children

Describes the development and evaluation of a pilot 12-session, school-based preventive intervention designed to enhance resilience among inner-city children who have experienced major life stress. Thirty-six 4th–6th grade children participated in the intervention in groups of 5–8 co-led by school personnel. The curriculum focussed on understanding feelings in oneself and others, perspective-taking, social problem-solving, dealing with solvable and unsolvable problems, and building self-efficacy and esteem. Pre-post evaluation showed significant improvement among participants on teacher-rated indices of learning problems and task orientation and on child ratings of perceived self-efficacy, realistic control attributions and anxiety. Program limitations and factors that restrict generalization are considered and new directions for program development and research are proposed.     

Embarazo gemelar con feto sano y mola completa como origen de enfermedad trofoblástica gestacional persistente: caso clínico

We describe and analyse the case of a multiple dizygotic pregnancy, formed by a genotypically and morphologically healthy foetus with a complete hydatidiform mole that ended in a preterm birth in the 2nd trimester due to maternal hypertension complications; after the evacuation of both foetus and the molar tissue, the patient developed a post-gestational Trophoblastic Neoplastic disease. We would like to focus on this pathology, looking at cases where the disease occurs in a twin gestation, explaining the diagnostic procedure and subsequent medical management of the persistent phase of gestational trophoblastic disease.     

MicroRNA-532-5p Regulates Pericyte Function by Targeting the Transcription Regulator BACH1 and Angiopoietin-1

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Anatomic shoulder replacement for primary osteoarthritis in patients over 80 years

Background and purpose — Anatomic total shoulder arthroplasty (TSA) gives good outcome in the treatment of primary osteoarthritis, but it is not known whether this also applies to patients over 80 years old.

Patients and methods — We retrospectively assessed outcome in patients over the age of 80 after anatomic TSA, performed for primary osteoarthritis with a preoperative intact rotator cuff (group O, n = 32). We compared it with outcome in a group of patients under the age of 70 (group Y, n = 32). Subjective outcome, Constant score, and radiological findings were analyzed.

Results — At a mean follow-up time of 7 years, there were no statistically significant differences between the groups. In group O, 24 patients were very satisfied and in group Y, 23 patients were very satisfied; the subjective shoulder value was 81% in both groups. Mean Constant score was 65 in group O and 67 in group Y. Moderate or severe radiological upper migration of the humeral head was detected in 1 patient in group O and in 3 patients in group Y. One patient in group Y was revised for glenoid loosening.

Interpretation — Good to excellent results can be expected after anatomic TSA in patients over the age of 80. Our findings suggest that they have similar results to those in patients around 70 years of age.     

Structural insight into the molecular mechanism of allosteric activation of human cystathionine β-synthase by S-adenosylmethionine

Cystathionine β-synthase (CBS) is a heme-dependent and pyridoxal-5′-phosphate–dependent protein that controls the flux of sulfur from methionine to cysteine, a precursor of glutathione, taurine, and H₂S. Deficiency of CBS activity causes homocystinuria, the most frequent disorder of sulfur amino acid metabolism. In contrast to CBSs from lower organisms, human CBS (hCBS) is allosterically activated by S-adenosylmethionine (AdoMet), which binds to the regulatory domain and triggers a conformational change that allows the protein to progress from the basal toward the activated state. The structural basis of the underlying molecular mechanism has remained elusive so far. Here, we present the structure of hCBS with bound AdoMet, revealing the activated conformation of the human enzyme. Binding of AdoMet triggers a conformational change in the Bateman module of the regulatory domain that favors its association with a Bateman module of the complementary subunit to form an antiparallel CBS module. Such an arrangement is very similar to that found in the constitutively activated insect CBS. In the presence of AdoMet, the autoinhibition exerted by the regulatory region is eliminated, allowing for improved access of substrates to the catalytic pocket. Based on the availability of both the basal and the activated structures, we discuss the mechanism of hCBS activation by AdoMet and the properties of the AdoMet binding site, as well as the responsiveness of the enzyme to its allosteric regulator. The structure described herein paves the way for the rational design of compounds modulating hCBS activity and thus transsulfuration, redox status, and H₂S biogenesis.Cystathionine β-synthase (CBS; EC 4.2.1.22) is a pyridoxal-5′-phosphate (PLP)-dependent enzyme that catalyzes the β-replacement of the hydroxyl group of l-serine (Ser) by l-homocysteine (Hcy), yielding cystathionine (Cth) (1). A deficient activity of human CBS (hCBS) is the cause of classical homocystinuria [CBS-deficient homocystinuria (CBSDH); Online Mendelian Inheritance in Man (OMIM) no. 236200], an autosomal, recessive inborn error of sulfur amino acid metabolism, characterized by increased levels of Hcy in plasma and urine. CBSDH manifests as a combination of connective tissue defects, skeletal deformities, vascular thrombosis, and mental retardation (2).The hCBS is a homotetrameric enzyme whose subunits are organized into three structural domains. The N-terminal region binds heme and is thought to function in redox sensing and/or enzyme folding (3, 4). The central catalytic core shows the fold of the type II family PLP-dependent enzymes (5, 6). Finally, the C-terminal region consists of a tandem pair of CBS motifs (7–9) that bind S-adenosylmethionine (AdoMet) and lead to an increase in catalytic activity by up to fivefold (10, 11). The CBS motif pair, commonly known as a “Bateman module” (12, 13), is responsible for CBS subunit tetramerization (14, 15). The presence of pathogenic missense mutations in this region often does not impair enzyme activity but typically interferes with binding of AdoMet and/or the enzyme’s activation by AdoMet (15–17). Removal of the regulatory region leads to a dimer with much increased activity (14, 15). Recently, we showed that removal of residues 516–525, forming a flexible loop of the CBS2 motif of hCBS, yields dimeric species (hCBSΔ516–525) with intact AdoMet binding capacity and activity responsiveness to AdoMet similar to a native hCBS WT (18).hCBS is regulated by a complex molecular mechanism that remains poorly understood. More than a decade ago, we and others hypothesized that hCBS might exist in two different conformations: a “basal” state with low activity, where the C-terminal regulatory domain would restrict the access of substrates into the catalytic site, and an AdoMet-bound “activated” state, where the AdoMet-induced conformational change would allow for enzyme activation (16, 19). Recently, we have unveiled the relative orientations of the regulatory and catalytic domains in hCBS (18), which were in a striking contrast to those of both the previous in silico models (20, 21) and the Drosophila melanogaster (dCBS) structure (22). Our data showed that, although the pairing mode and the orientation of catalytic cores are similar in both insect dCBS and hCBS, the position of their regulatory domains is markedly different (18). In the basal state, the Bateman modules from each hCBS unit are far apart and do not interact with each other, being placed just above the entrance of the catalytic site of the complementary subunit, thus hampering the access of substrates into this cavity. Our hCBSΔ516–525 structure additionally revealed the presence of two major cavities in the Bateman module, S1 and S2, one of which (S2) is solvent-exposed and probably represents the primary binding site for AdoMet (18). These findings are in agreement with the much higher basal activity of dCBS and its inability to bind or to be regulated by AdoMet (23, 24) and suggest that the structural basis underlying the regulation of the human enzyme markedly differs from CBS regulation in insects or yeast (24). Taken together, the available data indicate that binding of AdoMet to the Bateman module weakens the interaction between the regulatory domain and the catalytic core although the mechanism and the magnitude of the underlying structural effect are still under debate (16, 19, 25–27).To solve the molecular mechanism of hCBS regulation by AdoMet, we have analyzed the crystals of an engineered hCBSΔ516–525 protein that bears the mutation E201S, which potentially weakens and/or disrupts the interaction between the Bateman module and the catalytic core (Fig. 1A), thus favoring the activation of the enzyme. The data presented here fill a long-sought structural gap by unraveling the crystal structure of AdoMet-bound hCBS, thus providing the overall fold of the enzyme in its activated conformation and the identity of the AdoMet binding sites. Comparison with the structures of hCBS in basal conformation and constitutively activated dCBS was instrumental in the understanding of the regulatory role played by the C-terminal domain as well as the effect of some of the pathogenic mutations in the activation and/or inhibition of this key molecule of transsulfuration.Open in a separate windowFig. 1.Interactions between protein domains in basal hCBS. (A) In hCBSΔ516–525, residues Y484, N463, and S466 anchor the Bateman module (blue) to the protein core (gray) through H-bonds with the residues E201 and D198 from the loop L191–202, thus occluding the entrance to the catalytic pocket. (B) The CBS-specific activity of selected hCBS variants in the absence (blue bars) and the presence (red bars) of 300 µM AdoMet. hCBS enzyme species marked with “Δ” lack residues 516–525 and form dimers.     

Optimized venous return with a self-expanding cannula: from computational fluid dynamics to clinical application

The Smart canula concept allows for collapsed cannula insertion, and self-expansion within a vein of the body. (A) Computational fluid dynamics, and (B) bovine experiments (76+/-3.8 kg) were performed for comparative analyses, prior to (C) the first clinical application. For an 18F access, a given flow of 4 l/min (A) resulted in a pressure drop of 49 mmHg for smart cannula versus 140 mmHg for control. The corresponding Reynolds numbers are 680 versus 1170, respectively. (B) For an access of 28F, the maximal flow for smart cannula was 5.8+/-0.5 l/min versus 4.0+/-0.1 l/min for standard (P<0.0001), for 24F 5.5+/-0.6 l/min versus 3.2+/-0.4 l/min (P<0.0001), and for 20F 4.1+/-0.3 l/min versus 1.6+/-0.3 l/min (P<0.0001). The flow obtained with the smart cannula was 270+/-45% (20F), 172+/-26% (24F), and 134+/-13% (28F) of standard (one-way ANOVA, P=0.014). (C) First clinical application (1.42 m2) with a smart cannula showed 3.55 l/min (100% predicted) without additional fluids. All three assessment steps confirm the superior performance of the smart cannula design.