Applying the theory of planned behaviour to understand mental health professionals' intentions to work using a human rights-based approach in acute inpatient settings.

BACKGROUND: There has been a shift to implement human rights-based approaches in acute mental health care due to increasing concerns around quality of care. National Health Service (NHS) Trusts have a legal duty to uphold a person's human rights, therefore it is important to understand what any barriers might be. Using psychological theory may help to develop this understanding. AIM: To test whether the theory of planned behaviour can be an effective model in understanding mental health professionals' intentions to work using a human rights-based approach. METHOD: Participants were recruited from two NHS Trusts in the North West of England. A cross-sectional, survey design was used to examine mental health professionals' intentions to use human rights-based approaches. RESULTS: Multiple regression analyses were performed on the theory of planned behaviour constructs showing that attitude and subjective norm significantly predicted intention. Perceived behavioural control did not add any significant variance, nor any demographic variables. CONCLUSION: There could be factors outside of the individual clinician's control to fully work within a human rights-based framework on acute mental health wards. The theory of planned behaviour offers some understanding, however further development work into measuring human rights outcomes on acute mental health wards is needed.

Comparison of Neuropsychological Assessment by Videoconference and Face to Face.

OBJECTIVE: To compare the administration of neuropsychological tests by teleneuropsychology (TeleNP) and face to face (F-F) in order to determine the feasibility and reliability of TeleNP. METHOD: At the inclusion visit, all participants underwent a traditional F-F neuropsychological assessment as part of their standard care. Four months after inclusion, they were randomized to undergo an additional neuropsychological assessment either by F-F administration or by TeleNP. RESULTS: A total of 150 adults with cognitive complaints, but with no major cognitive or sensorial impairment were included. At 4 months, 69 participants were randomized in the F-F arm and 71 in TeleNP arm (10 lost in the follow-up). The overall satisfaction was high: 87.1% in the TeleNP arm were "very satisfied", and 82.9% indicated no preference between F-F and TeleNP. In agreement with previous data from the literature, neuropsychological assessments gave similar results across both administration conditions for a large majority of tests [Mini-Mental State Examination (MMSE), Free and Cued Selective Reminding Test (FCSRT) French version, Mahieux gestural praxis battery, Frontal Assessment Battery (FAB), time of completion of the Trail making Test (TMT) A and B, number of errors of the TMT B, Rey complex figure test, categorical et phonological verbal fluency tests] and minor differences for others [80-picture naming test (DO-80), FAB, Digit Span forward and backward and number of errors in the TMT A]. CONCLUSIONS: TeleNP is a promising method to be able to test patients as an alternative to F-F condition. Before this procedure can be generalized, it is now necessary to standardize the adaptation of certain tests and to test them in populations with more significant cognitive disorders.

Pattern of myocardial 99mTc-HMDP uptake and impact on myocardial function in patients with transthyretin cardiac amyloidosis.

AIMS: The purpose of the study was to describe the pattern of 99mTc-labeled phosphate agents myocardial uptake by scintigraphy and explore its impact on left ventricular (LV) functions in transthyretin cardiac amyloidosis (TTR-CA). METHODS: Fifty patients with TTR-CA underwent 99mTc- hydroxymethylene-diphosphonate (99mTc-HMDP) scintigraphy and echocardiography with measure of LV thickness, longitudinal strain (LS), systolic and diastolic functions. Cardiac retention by scintigraphy was assessed by visual scoring and the heart/whole body (H/WB) ratio was calculated by dividing counts in the heart by counts in late whole-body images. RESULTS: The mean population age was 79 ± 10 years. Mean H/WB ratio was 12 ± 7. Myocardial 99mTc-HMDP uptake on segments 5, 6, 7, 8, 11, 12, 13, 14, 16, and 17 was correlated with H/WB ratio. Mean LVEF and global LS were 51 ± 10% and - 10 ± 3%, respectively. H/WB ratio was correlated with global LS (R = 0.408, P = .003), Ea (R = - 0.566, P < .001) and mean left ventricular wall thickness (R = 0.476, P < .001) but not with LVEF (R = - 0.109, P = .453). Segmental myocardial uptake was slightly correlated with segmental LS (R = 0.152, P < .001). H/WB ratio was not correlated with NT-proBNP levels (R = 0.219, P = .148) neither E/Ea ratio (R = 0.204, P = .184). CONCLUSION: These findings show the relationship between bone tracer myocardial uptake and LV functions in patients with TTR cardiac amyloidosis.

Interest of chromosomal microarray analysis in the prenatal diagnosis of fetal intrauterine growth restriction.

OBJECTIVE: The aim of this study is to evaluate the diagnostic utility of prenatal diagnosis using the chromosomal microarray analysis (CMA) for fetuses presenting with isolated or associated intrauterine growth restriction (IUGR). METHOD: We retrospectively included all fetuses with IUGR referred for prenatal testing and studied by rapid fluorescence in situ hybridization (FISH), karyotype, and CMA. RESULTS: Among the 162 IUGR fetuses (78 associated and 84 isolated IUGR) included, 15 had an abnormal FISH result: 10 associated and five isolated fetal IUGRs. Among the 143 fetuses studied by CMA, 10 (7%) presented pathogenic copy number variations (CNVs). All 10 were in the associated fetal IUGR group (10/65 or 15.4%; 95% confidence interval [CI]: 8.4%-26.2%) versus 0/78 in the isolated fetal IUGR group (95% CI: 0%-5.6%). Six fetuses (4.2%) carried variants of unknown significance (VOUS) (three associated and three isolated fetal IUGRs). CONCLUSION: Our study highlights the added value of CMA in the case of associated fetal IUGR with an incremental yield of 6.1% (4/65) over karyotyping. No pathogenic CNVs were reported in the isolated fetal IUGR group. More studies must be conducted to determine when and whether CMA would be wisely indicated in this population.

Human amniotic membrane for guided bone regeneration of calvarial defects in mice.

Due to its biological properties, human amniotic membrane (hAM) is widely studied in the field of tissue engineering and regenerative medicine. hAM is already very attractive for wound healing and it may be helpful as a support for bone regeneration. However, few studies assessed its potential for guided bone regeneration (GBR). The purpose of the present study was to assess the potential of the hAM as a membrane for GBR. In vitro, cell viability in fresh and cryopreserved hAM was assessed. In vivo, we evaluated the impact of fresh versus cryopreserved hAM, using both the epithelial or the mesenchymal layer facing the defect, on bone regeneration in a critical calvarial bone defect in mice. Then, the efficacy of cryopreserved hAM associated with a bone substitute was compared to a collagen membrane currently used for GBR. In vitro, no statistical difference was observed between the conditions concerning cell viability. Without graft material, cryopreserved hAM induced more bone formation when the mesenchymal layer covered the defect compared to the defect left empty. When associated with a bone substitute, such improved bone repair was not observed. These preliminary results suggest that cryopreserved hAM has a limited potential for GBR.

Ethnic differences in diabetes prevalence and ICT use.

BACKGROUND: Uptake of information and communication technology (ICT) by individuals with diabetes can assist nursing care delivery, and improve patient outcomes. However, it is unclear how such uptake relates to ethnic differences in diabetes risk. AIM: To assess the moderating effects of ICT uptake on South Asian excess diabetes prevalence over a specific elapsed timeframe, accounting for selected environmental, socio-economic, and behavioural risk factors. METHOD: Archived data from a UK Office for National Statistics household survey 2006-2011 (120 621 partly non-orthogonal participant records) were analysed using hierarchical binary logistic regression analyses. RESULTS: ICT uptake qualified ethnic differences in diabetes prevalence. Non-smoking diabetes cases living in terraced housing with a home computer were more likely to be South Asian than Caucasian. By contrast, such cases were more likely to be Caucasian if a computer was unavailable (OR: 0.61; CI: 0.43-0.86; P=0.005). Furthermore, diabetes cases from low-income, mobile-dependent homes were probably South Asian (OR: 0.05; CI: 0.00-0.50; P=0.012). CONCLUSIONS: Home computing was linked to better tobacco control among South Asians with diabetes living in terraced properties. Mobile phone dependence was pronounced in those that received income support. Implications for nursing care are considered.

Pattern of secretion of pregnancy-associated plasma protein-A (PAPP-A) during pregnancies complicated by fetal aneuploidy, in vivo and in vitro.

BACKGROUND: Pregnancy-associated placental protein-A (PAPP-A) is a metalloprotease which circulates as an hetero-tetramer in maternal blood. Its maternal serum concentration in fetal trisomy 21 is decreased during the first trimester, so that PAPP-A is a useful screening biomarker. However, the regulation of PAPP-A placental secretion is unclear. We therefore investigated the secretion of PAPP-A in pregnancies complicated by fetal aneuploidies, both in vivo and in vitro. METHODS: Maternal serum collected between 10 WG and 33 WG during 7014 normal pregnancies and 96 pregnancies complicated by fetal trisomy 21, 18, and 13 were assayed for PAPP-A using the Immulite 2000xpi system®. The pregnancies were monitored using ultrasound scanning, fetal karyotyping and placental analysis. Villous cytotrophoblasts were isolated from normal and trisomic placenta and cultured to investigate PAPP-A secretion in vitro (n=6). RESULTS: An increased nuchal translucency during the first trimester is a common feature of many chromosomal defect but each aneuploidy has its own syndromic pattern of abnormalities detectable at the prenatal ultrasound scanning and confirmed at the fetal examination thereafter. PAPP-A levels rise throughout normal pregnancy whereas in trisomy 21, PAPP-A levels were significantly decreased, but only during the first trimester. PAPP-A levels were decreased in trisomy 13 and sharply in trisomy 18, whatever the gestational age. In vitro, PAPP-A secretion was decreased in aneuploidy, and associated with decreased hCG secretion in Trisomy 21 and 18. These biochemical profiles did not appear to be linked to any specific histological lesions affecting the placenta. CONCLUSIONS: These profiles may reflect different quantitative and qualitative placental dysfunctions in the context of these aneuploidies.

Reproducibility of the 2016 American Society of Echocardiography-European Association of Cardiovascular Imaging Algorithm for Estimation of Left Ventricular Filling Pattern: Not Perfect but Good Enough.

The 2016 American Society of Echocardiography (ASE) and European Association of Cardiovascular Imaging (EACVI) guidelines for the evaluation of left ventricular diastolic function reported a new algorithm to assess diastolic function and to estimate left ventricular filling pressure (LVFP). At least five to six different parameters were necessary to conclude, each of them with their own inter-observer variability. This article examines the reproducibility of each parameter of the algorithm and its influence on the final decision of the clinician. Echocardiographic exams of 12 non-selected patients without any known cardiac disease or follow-up but addressed to the hospital for symptoms were analyzed by two readers (one junior and one senior) in five French cardiologic tertiary centers. Inter-observer reproducibility at each step of the algorithm and final decision were analyzed. There was mild agreement on the final decision. The main reasons of discrepancy were disagreement on the significance of mitral annular calcifications and measured values that are just around the cut-off (despite good reproducibility, a slight variation could lead to misclassification of a dichotomous choice between a normal measure and a pathologic measure). Without considering performance, this multicentric French study puts forward limits to the actual algorithm recommended for LVFP pattern assessment. Agreement is excellent in caricatural (easy) cases (left ventricular pressure clearly normal or clearly elevated) but a great discordance exists in the gray zone. Improvement in the algorithm and in the method for LVFP determination is proposed.

Effectiveness and Safety of a Prolonged Hemodynamic Support by the IVAC2L System in Healthy and Cardiogenic Shock Pigs.

BACKGROUND: Mechanical circulatory supports are used in case of cardiogenic shock (CS) refractory to conventional therapy. Several devices can be employed, but are limited by their availability, benefit risk-ratio, and/or cost. AIMS: To investigate the feasibility, safety, and effectiveness of a long-term support by a new available device (IVAC2L) in pigs. METHODS: Experiments were carried out in male pigs, divided into healthy (n = 6) or ischemic CS (n = 4) groups for a median support time of 34 and 12 h, respectively. IVAC2L was implanted under fluoroscopic and TTE guidance under general anesthesia. CS was induced by surgical ligation of the left anterior descending artery. An ipsilateral lower limb reperfusion was created with the Solopath® system. Reperfusion was started after 1 h of support in healthy pigs and upon IVAC2L insertion in CS pigs. Hemodynamic and biological parameters were monitored before and during the whole period of support in each group. RESULTS: Occurrence of an ipsilateral lower limb ischemia was systematic in healthy and CS pigs in a few minutes after IVAC2L implantation, and could be reversed by the arterial reperfusion, as demonstrated by distal transcutaneous pressure in oxygen (TcPO2) and lactate normalization. IVAC2L support decreased pulmonary capillary wedge pressure (PCWP) (15.3 ± 0.3 vs. 7.5 ± 0.9 mmHg, p < 0.001), increased systolic blood pressure (SBP) (70 ± 4.5 vs. 101.3 ± 3.1 mmHg, p < 0.01), and cardiac output (CO) (4.0 ± 0.3 vs. 5.2 ± 0.6 l/min, p < 0.05) in CS pigs; at CS onset and after 12 h of support, without effects on heart rate or pulmonary artery pressure (PAP). Non-sustained ventricular arrhythmias were frequent at implantation (50%). A non-significant hemolysis was observed under support in CS pigs. Bleedings were frequent at the insertion and/or operating sites (30%). CONCLUSION: Long-term support by IVAC2L is feasible and associated with a significant hemodynamic improvement in a porcine model. These preclinical data open the door for a study of IVAC2L in human ischemic CS, keeping in mind the need for systematic reperfusion of the lower limb and the associated risk of bleeding.

Tip of the iceberg: a tertiary care centre retrospective study of left ventricular hypertrophy aetiologies.

AIMS: To phenotype patients referred to a tertiary centre for the exploration of a left ventricular hypertrophy (LVH) starting from 12 mm of left ventricular wall thickness (LVWT). METHODS AND RESULTS: Consecutive patients referred for aetiological workup of LVH, beginning at 12 mm of LVWT were retrospectively included in this tertiary single-centred observational study. Patients presenting with severe aortic stenosis were excluded. Aetiological workup was reviewed for each subject and aetiologies were adjudicated by expert consensus.Among 591 patients referred for LVH aetiological workup, 41% had a maximal LVWT below 15 mm. LVH aetiologies were led by cardiac amyloidosis (CA, 34.3%), followed by sarcomeric hypertrophic cardiomyopathy (S-HCM, 32.1%), hypertensive cardiomyopathy (21.7%), unknown aetiology (7.6%) and other (4.2%), including Anderson-Fabry's disease (1.7%). CA and S-HCM affected over 50% of patients with mild LVH (12-14 mm); the prevalence of these aetiologies rose with LVH severity. Among patients with Anderson-Fabry's disease, 4 (40%) had a maximal LVWT <15 mm. CONCLUSIONS: Mild LVH (ie, 12-14 mm) conceals multiple aetiologies that can lead to specific treatment, cascade family screening and specific follow-up. Overall, CA is nowadays the leading cause of LVH in tertiary centers.

Cyclic AMP-binding protein Epac1 acts as a metabolic sensor to promote cardiomyocyte lipotoxicity.

Cyclic adenosine monophosphate (cAMP) is a master regulator of mitochondrial metabolism but its precise mechanism of action yet remains unclear. Here, we found that a dietary saturated fatty acid (FA), palmitate increased intracellular cAMP synthesis through the palmitoylation of soluble adenylyl cyclase in cardiomyocytes. cAMP further induced exchange protein directly activated by cyclic AMP 1 (Epac1) activation, which was upregulated in the myocardium of obese patients. Epac1 enhanced the activity of a key enzyme regulating mitochondrial FA uptake, carnitine palmitoyltransferase 1. Consistently, pharmacological or genetic Epac1 inhibition prevented lipid overload, increased FA oxidation (FAO), and protected against mitochondrial dysfunction in cardiomyocytes. In addition, analysis of Epac1 phosphoproteome led us to identify two key mitochondrial enzymes of the the ß-oxidation cycle as targets of Epac1, the long-chain FA acyl-CoA dehydrogenase (ACADL) and the 3-ketoacyl-CoA thiolase (3-KAT). Epac1 formed molecular complexes with the Ca2+/calmodulin-dependent protein kinase II (CaMKII), which phosphorylated ACADL and 3-KAT at specific amino acid residues to decrease lipid oxidation. The Epac1-CaMKII axis also interacted with the α subunit of ATP synthase, thereby further impairing mitochondrial energetics. Altogether, these findings indicate that Epac1 disrupts the balance between mitochondrial FA uptake and oxidation leading to lipid accumulation and mitochondrial dysfunction, and ultimately cardiomyocyte death.

Impact of maternal pulmonary insufficiency on fetal growth in pregnancy.

Rationale: It is known that fetal growth is usually proportional to left-sided cardiac output (CO), which parallels the right-sided CO and that congenital right-sided lesions are usually associated with better perinatal outcomes than left-sided lesions.Objective: Our objective was to document whether newborns from mothers with severe residual pulmonary valve insufficiency (PI) after surgical tetralogy of Fallot (TOF) or pulmonary valve stenosis (PS) correction have lower birth weight (BW) than newborns from mothers with absent, mild, or moderate PI.Methods: This is a retrospective cohort study of women affected with repaired TOF and corrected PS with varied severity of residual PI. Exclusion criteria were: left ventricular dysfunction, left-sided valvular heart disease, other right-sided structural heart disease, chronic hypertension, substance addiction, and incomplete follow-up. Pregnancies were divided into three groups: absent or mild PI, moderate PI, and severe PI. A generalized linear model with normal dependent variable distribution was built and the parameter estimation made with Generalized Estimation Equations (GEE) to take into account repeated mother in data. Variables such as gestational age at birth, maternal age, smoking, and body mass index were tested with bivariate analyses to assess their effect on BW. Only gestational age remained in the adjusted model.Results: A total of 45 patients were included (33 TOF and 12 PS) and 97 pregnancies were reported: 22 miscarriages (22.7%) (15 TOF, 7 PS) and 75 successful pregnancies (57 TOF, 18 PS). The patients were divided into three groups: 1) absent or mild PI, 2) moderate PI, and 3) severe PI groups, which comprised, respectively, 29 (15 TOF, 4 PS), 20 (10 TOF, 1 PS), and 26 successful pregnancies (8 TOF, 7 PS). Using three levels of PI (absent or mild, moderate, and severe), the unadjusted model showed a significant effect of level of PI on BW (p = .0118), as well as the adjusted model (p = .0263) with gestational age as a covariate. The estimated mean newborn's BW was 3055.8 g in the severe PI group, 3151.0 g in the moderate PI group, and 3376.4 g in the absent or mild group when adjusted for gestational age. Hence, we estimated that the mean newborn's BW is 321 g lower in the severe PI group compared with absent or mild PI group ((CI: 572.3; -68.9), p = .0087).Conclusions: Pregnancy is usually well tolerated in repaired TOF and corrected PS. Severe PI either from repaired TOF or PS is at higher risk of lower newborn's BW. Special attention must be paid to the severity of PI. Fetal growth surveillance in the third trimester is warranted.

Rationale for the design of 3D-printable bioresorbable tissue-engineering chambers to promote the growth of adipose tissue.

Tissue engineering chambers (TECs) bring great hope in regenerative medicine as they allow the growth of adipose tissue for soft tissue reconstruction. To date, a wide range of TEC prototypes are available with different conceptions and volumes. Here, we addressed the influence of TEC design on fat flap growth in vivo as well as the possibility of using bioresorbable polymers for optimum TEC conception. In rats, adipose tissue growth is quicker under perforated TEC printed in polylactic acid than non-perforated ones (growth difference 3 to 5 times greater within 90 days). Histological analysis reveals the presence of viable adipocytes under a moderate (less than 15% of the flap volume) fibrous capsule infiltrated with CD68+ inflammatory cells. CD31-positive vascular cells are more abundant at the peripheral zone than in the central part of the fat flap. Cells in the TEC exhibit a specific metabolic profile of functional adipocytes identified by 1H-NMR. Regardless of the percentage of TEC porosity, the presence of a flat base allowed the growth of a larger fat volume (p < 0.05) as evidenced by MRI images. In pigs, bioresorbable TEC in poly[1,4-dioxane-2,5-dione] (polyglycolic acid) PURASORB PGS allows fat flap growth up to 75 000 mm3 at day 90, (corresponding to more than a 140% volume increase) while at the same time the TEC is largely resorbed. No systemic inflammatory response was observed. Histologically, the expansion of adipose tissue resulted mainly from an increase in the number of adipocytes rather than cell hypertrophy. Adipose tissue is surrounded by perfused blood vessels and encased in a thin fibrous connective tissue containing patches of CD163+ inflammatory cells. Our large preclinical evaluation defined the appropriate design for 3D-printable bioresorbable TECs and thus opens perspectives for further clinical applications.

Diagnostic score of cardiac involvement in AL amyloidosis.

AIMS: Early diagnosis of cardiac involvement is a key issue in the management of AL amyloidosis. Our objective was to establish a diagnostic score of cardiac involvement in AL amyloidosis and to compare it with the current consensus criteria [i.e. left ventricular hypertrophy >12 mm and N-terminal pro b-type natriuretic peptide (NT-proBNP) >332 ng/L]. METHODS AND RESULTS: We carried out a prospective and multicenter study on AL amyloidosis patients who underwent cardiac evaluation including clinical examination, electrocardiography (ECG), cardiac biomarkers, transthoracic echocardiography (TTE), and cardiac magnetic resonance imaging (CMR). Cardiac involvement was based on CMR and/or endomyocardial biopsy. In a derivation cohort of 114 patients (82 with cardiac involvement), the highest diagnostic accuracy was observed with NT-proBNP and troponin blood levels, TTE-derived global longitudinal strain (LS), and apical to basal LS gradient. By using multivariate analysis, we established a diagnostic score including global LS ≥-17% (1 point), apical/(basal + median) LS ≥0.90 (1 point), and troponin T >35 ng/L (1 point). A score >1 was associated with sensitivity of 94% and specificity of 97%, an area under the curve of 0.98 [95% confidence interval (CI) 0.93-0.99] as well as a net reclassification index of 0.39 (95% CI 0.28-0.46) when compared with consensus criteria. In a validation cohort of 73 AL amyloidosis patients, the area under the receiver operating characteristic curve of the diagnostic score was 0.97 (95% CI 0.90-0.99). CONCLUSION: Combining T troponin blood levels and two echo-derived strain parameters leads to very high accuracy for diagnosing cardiac involvement in AL amyloid patients.

Value of natriuretic peptides and tissue Doppler imaging in the estimation of left ventricular filling pressure in patients with cardiac amyloidosis.

Background: Estimation of left ventricular filling pressures (LVFP) is a determining factor in the follow-up of patients with cardiac amyloidosis (CA). Natriuretic peptides (NPs) and tissue Doppler imaging may be used to monitor LVFP in patients with CA. The aim of this study was to evaluate the value of NPs and Doppler parameters in estimating LVFP in patients with CA. Methods: Fifty patients with biopsy-verified light chain (n=31), A protein amyloidosis (AA) (n=1), apoliporotein A2 (n=1) or bone scintigraphy-proven transthyretin (n=17) CA were retrospectively included. All patients underwent right heart catheterisation (RHC). Among them, 48 (96%) and 43 (86%) had assays of NPs (20 brain natriuretic peptide (BNP), 27 N-terminal pro-hormone brain natriuretic peptide (NT-proBNP) and 1 both) and transthoracic echocardiography performed within 24 hours of RHC, respectively. Results: The median BNP and NT-proBNP levels were 1000 (243-1477) ng/L and 10 106 (2935-13 348) ng/L, respectively. Echocardiography demonstrated left atrial enlargement with a mean volume of 47±16 mL and low tissue Doppler lateral Ea of 5±2 cm/s. The mean early diastolic mitral inflow velocity on early lateral mitral annular diastolic velocity ratio (E/Ea) ratio was 18±7, and the mean pulmonary capillary wedge pressure (PCWP) by RHC was 18±8 mm Hg. There was no correlation between BNP (r=0.260, p=0.774) or NT-proBNP (r=-0.103, p=0.984) levels and PCWP. There was a slight correlation between E/Ea ratio and PCWP (r=0.337, p=0.029). E/Ea ratio >14 performed poorly in differentiating elevated and low LVFP. Conclusion: In patients with CA, NPs do not accurately estimate PCWP. Tissue Doppler-derived mitral E/Ea ratio is correlated with PCWP, but the slight correlation requires to estimate LVFP in a broad clinical and imaging context to avoid diagnostic errors.

Quantification of myocardial 99mTc-labeled bisphosphonate uptake with cadmium zinc telluride camera in patients with transthyretin-related cardiac amyloidosis.

PURPOSE: We aimed to compare different methods for semi-quantitative analysis of cardiac retention of bone tracers in patients with cardiac transthyretin amyloidosis (ATTR). METHODS: Data from 67 patients with ATTR who underwent both conventional whole-body scan and a CZT myocardial SPECT (DSPECT, Spectrum Dynamics) 3 h after injection of 99mTc-labeled bone tracer were analyzed. Visual scoring of cardiac retention was performed on whole-body scan according to Perugini 4-point grading system from 0 (no uptake) to 3 (strong cardiac uptake with mild/absent bone uptake). A planar heart-to-background (H:B) ratio was calculated using whole-body scan (wb-H:B). CZT SPECT was quantified using three methods: planar H:B ratio calculated from anterior reprojection (ant-H:B), left anterior oblique reprojection (LAO-H:B), and 3D-H:B ratio calculated from transaxial slices as mean counts in a VOI encompassing the heart divided by background VOI in the contralateral lung. Interventricular septal thickness was obtained using echocardiography. RESULTS: H:Bs obtained from planar and reprojected data were not statistically different (wb-H:B, 2.05 ± 0.64, ant-H:B, 1.97 ± 0.61, LAO-H:B, 2.06 ± 0.64, all p = ns). However, 3D-H:B was increased compared to planar H:Bs (3D-H:B, 4.06 ± 1.77, all p < 0.0001 vs. wb-H:B, ant-H:B, and LAO-H:B). Bland-Altman plots demonstrated that the difference between 3D and planar H:Bs increased with the mean value of myocardial uptake. 3D-H:B was best correlated to septal thickness (r = 0.45, p < 0.001). Finally, abnormal right ventricular uptake was associated with higher values of cardiac retention. CONCLUSION: 3D semi-quantitative analysis of CZT SPECT optimized the assessment of 99mTc-labeled bone tracer myocardial uptake in patients with cardiac amyloidosis.

Comparison of the impact of preservation methods on amniotic membrane properties for tissue engineering applications.

Human amniotic membrane (hAM) is considered as an attractive biological scaffold for tissue engineering. For this application, hAM has been mainly processed using cryopreservation, lyophilization and/or decellularization. However, no study has formally compared the influence of these treatments on hAM properties. The aim of this study was to develop a new decellularization-preservation process of hAM, and to compare it with other conventional treatments (fresh, cryopreserved and lyophilized). The hAM was decellularized (D-hAM) using an enzymatic method followed by a detergent decellularization method, and was then lyophilized and gamma-sterilized. Decellularization was assessed using DNA staining and quantification. D-hAM was compared to fresh (F-hAM), cryopreserved (C-hAM) and lyophilized/gamma-sterilized (L-hAM) hAM. Their cytotoxicity on human bone marrow mesenchymal stem cells (hBMSCs) and their biocompatibility in a rat subcutaneous model were also evaluated. The protocol was effective as judged by the absence of nuclei staining and the residual DNA lower than 50 ng/mg. Histological staining showed a disruption of the D-hAM architecture, and its thickness was 84% lower than fresh hAM (p < 0.001). Despite this, the labeling of type IV and type V collagen, elastin and laminin were preserved on D-hAM. Maximal force before rupture of D-hAM was 92% higher than C-hAM and L-hAM (p < 0.01), and D-hAM was 37% more stretchable than F-hAM (p < 0.05). None of the four hAM were cytotoxic, and D-hAM was the most suitable scaffold for hBMSCs proliferation. Finally, D-hAM was well integrated in vivo. In conclusion, this new hAM decellularization process appears promising for tissue engineering applications.

Cartography of the mechanical properties of the human amniotic membrane.

Because of its low immunogenicity, biological properties, and high availability, the Human Amniotic Membrane (HAM) is widely used in the clinic and in tissue engineering research. However, while its biological characteristics are well described, its mechanical properties remain understudied especially in terms of inter- and intra-HAM variability. To guide bioengineers in the use of this natural biomaterial, a detailed cartography of the HAM's mechanical properties was performed. Maximal force (Fmax) and strain at break (Smax) were identified as the relevant mechanical criteria for this study after a combined analysis of histological sections, thickness measurements after dehydration, and uniaxial tensile tests. Eight HAMs were studied by mechanical cartography using a standardized cutting protocol and sampling pattern. On average, 103 ±â€¯10 samples were retrieved and tested per HAM. Intra-tissue variability highlighted the fact that there were two mechanically distinct areas (placental and peripheral) in each HAM. For all HAMs, placental HAM was significantly stronger by 82 ±â€¯45% and more stretchable by 19 ±â€¯6% than their peripheral counterparts. Our results also demonstrated that placental, but not peripheral, HAM presented isotropic mechanical properties. Thus, placental HAM can be a raw material of choice that could be favored especially in the development of tissue engineering products where mechanical properties play a key role.