Measurement equivalence of touch‐screen computerized and paper‐based diabetes‐specific quality‐of‐life questionnaires

Current advances in technology have enabled the development of a computer‐based questionnaire that provides advantages over the paper‐based mode of administration, such as automatic data entry, storage and calculations. However, before implementing a computer‐based questionnaire, its equivalence with the original paper‐based questionnaire must first be demonstrated. The purpose of this study was to evaluate the measurement equivalence of the computerized Diabetes‐Specific Quality‐of‐Life questionnaire (cD‐QOL) with its original paper‐based counterpart. A two‐period crossover design was used in this study. The measurement equivalence was evaluated using quadratic weighted kappa coefficients, intraclass correlations and Cronbach's alpha comparisons. The cD‐QOL was equivalent to its original paper‐based counterpart. Participants preferred the cD‐QOL over the paper‐based questionnaire and reported that it was easy to use.     

Mn‐citrate and Mn‐HIDA: intermediate‐affinity chelates for manganese‐enhanced MRI

In this study we investigated two manganese chelates in order to improve the image enhancement of manganese‐enhanced MRI and decrease the toxicity of free manganese ions. Since both MnCl₂ and a low‐affinity chelate were associated with a slow continuous decrease of cardiac functions, we investigated intermediate‐affinity chelates: manganese N‐(2‐hydroxyethyl)iminodiacetic acid (Mn‐HIDA) and Mn‐citrate. The T₁ relaxivity values for Mn‐citrate (4.4 m m ^?1 s^?1) and Mn‐HIDA (3.3 m m ^?1 s^?1) in artificial cerebrospinal fluid (CSF) were almost constant in a concentration range from 0.5 to 5 m m at 37 °C and 4.7 T. In human plasma, the relaxivity values increased when the concentrations of these Mn chelates were decreased, suggesting the presence of free Mn²⁺ bound with serum albumin. Mn‐HIDA and Mn‐citrate demonstrated a tendency for better contractility when employed with an isolated perfused frog heart, compared with MnCl₂. Only minimal changes were demonstrated after a venous infusion of 100 m m Mn‐citrate or Mn‐HIDA (8.3 µmol kg^?1 min^?1) in rats and a constant heart rate, arterial pressure and sympathetic nerve activity were maintained, even after breaking the blood–brain barrier (BBB). Mn‐citrate and Mn‐HIDA could not cross the intact BBB and appeared in the CSF, and then diffused into the brain parenchyma through the ependymal layer. The responses in the supraoptic nucleus induced by the hypertonic stimulation were detectable. Therefore, Mn‐citrate and Mn‐HIDA appear to be better choices for maintaining the vital conditions of experimental animals, and they may improve the reproducibility of manganese‐enhanced MRI of the small nuclei in the hypothalamus and thalamus. Copyright © 2012 John Wiley & Sons, Ltd.     

Endothelium‐dependent and endothelium‐independent effects of 1‐nitro‐2‐propylbenzene on rat aorta

A group of nitro compounds contains a benzene ring in a short aliphatic chain with the NO₂ group, property that supposedly favors its vasodilator profile. In this study, we evaluated in isolated rat aorta the effects of 1‐nitro‐2‐propylbenzene (NPB), a nitro compound containing the NO₂ in the aromatic ring. In aorta precontracted with KCl, NPB (1‐3000 μm ) induced full endothelium‐independent relaxation. In endothelium‐intact preparations, phenylephrine‐induced contractions were fully relaxed by NPB, effect unaltered by N(ω)‐nitro‐L‐arginine methyl ester (L‐NAME) or 1H‐[1,2,4]oxadiazolo[4,3‐a]quinoxalin‐1‐one (ODQ). In the concentration range of 30–300 μm , NPB slightly but significantly potentiated the phenylephrine‐induced contraction. Such potentiation was unaltered by the thromboxane‐prostanoid receptor antagonist seratrodast, but was abolished by endothelium removal or by preincubation of endothelium‐intact preparations with L‐NAME, ODQ or by ruthenium red and HC‐030031, blockers of subtype 1 of ankyrin transient receptor potential (TRPA₁) channels. Verapamil exacerbated the potentiating effect of NPB. The potentiating effect was undetectable in preparations precontracted by 9,11‐dideoxy‐11α,9α‐epoxymethanoprostaglandin F2α (U‐46619). Relaxation was reduced by ruthenium red while it was enhanced by HC‐030031. In conclusion, NPB has vasodilator properties but with a mechanism of action distinct from its analogues. Contrary to other nitro compounds, its relaxing effects did not involve recruitment of the guanylyl cyclase pathway. NPB has also endothelium‐dependent potentiating properties on phenylephrine‐induced contractions, a phenomenon that putatively required a role of endothelial TRPA₁ channels. The present findings reinforce the notion that the functional group NO₂ in the aliphatic chain of these nitro compounds determines favorably their vasodilator properties.     

Synthesis and characterization of poly(glycerol‐co‐sebacate‐co‐ε‐caprolactone) elastomers

In this study, poly(glycerol‐co‐sebacate‐co‐ε‐caprolactone) (PGSCL) elastomers were synthesized for the first time from the respective monomers. The structural analysis of PGSCL elastomers by nuclear magnetic resonance (¹H‐NMR) and Fourier transform infrared spectroscopy (FTIR) revealed that the elastomers have a high number of hydrogen bonds and crosslinks. X‐ray diffraction (XRD) and thermal analysis indicated an amorphous state. Differential scanning calorimetry (DSC) analysis showed that the elastomers has a glass transition temperature (T_g) of –36.96°C. The Young's modulus and compression strength values were calculated as 46.08 MPa and 3.192 MPa, respectively. Calculations based on acid number and end groups analysis revealed a number average molecular weight of 148.15 kDa. Even though the foaming studies conducted by using supercritical CO₂ resulted in a porous structure; the obtained morphology tended to disappear after 48 h, leaving small cracks on the surface. This phenomenon was interpreted as an indication of self‐healing due to the high number of hydrogen bonds. The PGSCL elastomers synthesized in this study are flexible, robust to compression forces and have self‐healing capacity. Thanks to good biocompatibility and poor cell‐adhesion properties, the elastomers may find diverse applications where a postoperative adhesion barrier is required. Copyright © 2013 John Wiley & Sons, Ltd.     

Synthesis and characterization of new low‐molecular‐weight lysine‐conjugated Gd‐DTPA contrast agents

Various blood pool contrast agents (CAs), characterized by intravascular distribution, have been developed to assist contrast enhanced magnetic resonance angiography (MRA). Among these CAs, the DTPA derivatives conjugated to synthetic polypeptides, such as polylysine, represent attractive candidates for blood pool imaging. However, due to the presence of charged residues located on their backbone, these agents are retained in the kidneys and this compromises their long blood half‐life. In order to overcome this major drawback of the polylysine compounds, two new low‐molecular‐weight CAs were synthesized in the present work by conjugating four or six 1‐p‐isothiocyanatobenzyl‐DTPA moieties to tri‐ or penta‐Lys peptides [(Gd‐DTPA)₄Lys₃ and (Gd‐DTPA)₆Lys₅], respectively. All the –NH₂ groups of Lys were thus blocked by covalent conjugation to DTPA. The stability and relaxometric properties of these compounds, as well as their pharmacokinetic and biodistribution characteristics, were then evaluated. The half‐life in blood of these new polylysine derivatives, as determined in rats, is twofold longer than that of Gd‐DTPA. The compounds could thus be optimal blood pool markers for MRA, which typically uses fast acquisition times. The absence of positive molecular charge did not limit their retention in kidneys 2 h after administration. On the other hand, (Gd‐DTPA)₄Lys₃ is retained in kidneys to a lesser extent than (Gd‐DTPA)₆Lys₅. Their moderate retention in blood and their higher stability and relaxivity in comparison with Gd‐DTPA highlight these polylysine derivatives as optimal compared with previously developed polylysine compounds. Copyright © 2010 John Wiley & Sons, Ltd.     

D‐ and L‐[123I]‐2‐I‐phenylalanine show a long tumour retention compared with D‐ and L‐[123I]‐2‐I‐tyrosine in R1M rhabdomyosarcoma tumour‐bearing Wag/Rij rats

The aim of this study was the comparison of the tumour uptake and the long‐term retention of [¹²³I]‐2‐I‐L ‐phenylalanine and [¹²³I]‐2‐I‐D ‐phenylalanine with those of [¹²³I]‐2‐I‐L ‐tyrosine and [¹²³I]‐2‐I‐D ‐tyrosine in R1M rhabdomyosarcoma tumour‐bearing rats. The biodistribution of the radioactivity as a function of time in R1M tumour‐bearing rats was measured by planar gamma camera imaging (dynamic and static). If dissection was applied, the activity in the tumours and tissues of interest was measured by gamma counting. [¹²³I]‐2‐iodo‐L ‐phenylalanine, [¹²³I]‐2‐iodo‐D ‐phenylalaine, [¹²³I]‐2‐I‐L ‐tyrosine showed a considerable tumour uptake reaching a maximum between 10 and 30 min. At 30 min p.i. the differential uptake ratio values of this uptake were, respectively, 2.1, 2.3, 2.5 and 1.7. The activity in the tumour was shown to be related to a tumour cell uptake and not to an increased blood pool activity. All the tracers showed a clearance from the blood to the bladder without renal retention. At longer times both L ‐ and D ‐ [¹²³I]‐2‐I‐tyrosine were cleared for a large part from the tumours and the body. [¹²³I]‐2‐I‐L ‐Phe and [¹²³I]‐2‐I‐D ‐Phe showed a considerable and equal retention in the tumours: as compared with 0.5 h, 91% at 24 h and 80% at 48 h. This was related to the longer retention of activity in the blood pool noticed for these compounds (81% at 24 h and 65% at 48 h). The tumour‐to‐background ratio increased with 25% at those longer times. At short times all the tracers were taken up to a considerable extent in the tumours. In the R1M‐bearing Wag/Rij rat model only [¹²³I]‐2‐I‐L ‐phenylalanine and [¹²³I]‐2‐I‐D ‐phenylalanine showed an especially high retention at long times without any significant difference between the enantiomers. Copyright © 2007 John Wiley & Sons, Ltd.     

Spray‐ and laser‐assisted biomaterial processing for fast and efficient autologous cell‐plus‐matrix tissue engineering

At present, intensive investigation aims at the creation of optimal valvular prostheses. We introduced and tested the applicability and functionality of two advanced cell‐plus‐matrix seeding technologies, spray‐assisted bioprocessing (SaBP) and laser‐assisted bioprocessing (LaBP), for autologous tissue engineering (TE) of bioresorbable artificial grafts. For SaBP, human mesenchymal stem cells (HMSCs), umbilical cord vein endothelial cells (HUVECs) and fibrin were simultaneously spray‐administered on poly(ε‐caprolactone) (PCL) substrates. For LaBP, HUVECs and HMSCs were separately laser‐printed in stripes, followed by fibrin sealing. Three‐leaflet valves were manufactured following TE of electrospun PCL tissue equivalents. Grafts were monitored in vitro under static and dynamic conditions in bioreactors. SaBP and LaBP resulted in TE of grafts with homogeneous cell distribution and accurate cell pattern, respectively. The engineered valves demonstrated immediate sufficient performance, complete cell coating, proliferation, engraftment, HUVEC‐mediated invasion, HMSC differentiation and extracellular matrix deposition. SaBP revealed higher efficiency, with at least 12‐fold shorter processing time than the applied LaBP set‐up. LaBP realized coating with higher cell density and minimal cell–scaffold distance. Fibrin and PCL stability remain issues for improvement. The introduced TE technologies resulted in complete valvular cell‐plus‐matrix coating, excellent engraftment and HMSCs differentiation. SaBP might have potential for intraoperative table‐side TE considering the procedural duration and ease of implementation. LaBP might accelerate engraftment with precise patterns. Copyright © 2012 John Wiley & Sons, Ltd.     

Two‐ and three‐dimensional prenatal sonographic diagnosis of prune‐belly syndrome

We report the prenatal diagnosis of 6 cases of Prune‐belly syndrome in the 2^nd trimester. The sonographic diagnosis was based on the findings of oligohydramnios, renal anomalies, and a lower abdominal cystic mass representing the abnormal dilatation of the bladder on conventional 2‐dimensional sonographic examination. We discuss the role of Doppler imaging and 3‐dimensional sonography as complementary methods to conventional sonography. Four of our 6 cases were confirmed with associated defects. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010     

A case‐control study and meta‐analysis reveal the association between COX‐2 G‐765C polymorphism and primary end‐stage hip and knee osteoarthritis

Background

Osteoarthritis (OA) is a popular arthrosis featured as pain, limited joint activity, and deformity. Cyclooxygenase‐2 (COX‐2) has been reported to be up‐regulated in arthritic tissues and is integral to the progression of osteoarthritis (OA). Previous studies showed the COX‐2 promoter G‐765C polymorphism could influence COX‐2 expression. However, the relationship between the variant and OA risk is contrasting.

Methods

We conducted a case‐control study with 196 primary end‐stage hip and knee OA cases and 196 controls in a Chinese Han population. Subsequently, we integrated this case‐control study in a meta‐analysis to acquire greater statistical power. The results from our case‐control study using MassARRAY genotyping technology and binary logistic regression statistical methods.

Results

The variant carriers in the Chinese Han population had a lower primary end‐stage hip and knee OA susceptibility (C vs G: OR = 0.350, 95%CI: 0.154‐0.797, P = .012; GC vs GG: adjusted OR = 0.282, 95%CI: 0.118‐0.676, P = .005). Stratification studies indicated that a higher GC frequency in women decreased not only knee OA susceptibility but also unilateral knee OA risk. The meta‐analysis showed that the variant exhibited a significantly decreased OA risk through comparisons involving allelic, homozygous, heterozygous, and dominant models.

Conclusion

Our findings suggest that the COX‐2 G‐765C polymorphism exerts a protective effect against primary end‐stage knee osteoarthritis in a female Chinese Han population.

     

Performance of CURB‐65 and CURB‐age in community‐acquired pneumonia

Background: Community‐acquired pneumonia (CAP) is common and associated with significant mortality. In this study, we validated a newly proposed severity assessment rule for CAP, CURB‐age, and also compared with to the currently recommended criteria in UK, CURB‐65. Methods: We conducted a prospective study in three hospitals in Norfolk and Suffolk, UK. One hundred and ninety patients were included and followed up for 6 weeks. Results: Of 190 patients, 100 were men (53%). The age range was 18–101 years (median 76 years). Sixty‐five (34%) had severe pneumonia by CURB‐65 and 54 (28%) had severe pneumonia by CURB‐age. There were 54 deaths during follow‐up. There were 32 deaths (50%) in severe and 22 deaths (18%) in non‐severe group by CURB‐65. There were 27 deaths each in both the groups by CURB‐age (50% of severe cases and 20% of non‐severe cases). For CURB‐65, sensitivity, specificity, and positive and negative predictive values were 59.3% (45.0–72.4), 75.7% (67.6–82.7), 49.2% (36.6–61.9) and 82.4% (74.6–88.6), respectively. For CURB‐age, the respective values were 50.0% (31.1–63.9), 80.1% (72.4–86.5), 50.0% (36.1–63.9) and 80.1% (72.4–86.5). Exclusion of patients aged < 65 years did not alter the results. Conclusions: Despite better specificity in correctly identifying 6‐week mortality for CAP, CURB‐age appears to be less sensitive than CURB‐65. Our findings further assure the usefulness of CURB‐65 for predicting mortality in CAP.