Significant Association of Serum Albumin With the Severity of Coronary Microvascular Dysfunction Using Dynamic CZT-SPECT.

OBJECTIVE: Both low serum albumin (SA) concentration and coronary microvascular dysfunction (CMD) are risk factors for the development of heart failure (HF). We hypothesized that SA concentration is associated with myocardial flow reserve (MFR) and implicated in pathophysiological mechanism of HF. METHODS: We retrospectively studied 454 patients undergoing dynamic cardiac cadmium-zinc-telluride myocardial perfusion imaging from April 2018 to February 2020. The population was categorized into three groups according to SA level (g/dL): Group 1: >4, Group 2: 3.5-4, and Group 3: <3.5. Myocardial blood flow (MBF) and myocardial flow reserve (MFR, defined as stress/rest MBF ratio) were compared. RESULTS: The mean age of the whole cohort was 66.2 years, and 65.2% were men. As SA decreased, stress MBF (mL min-1 g-1) and MFR decreased (MBF: 3.29 ± 1.03, MFR: 3.46 ± 1.33 in Group 1, MBF: 2.95 ± 1.13, MFR: 2.51 ± 0.93 in Group 2, and MBF: 2.64 ± 1.16, MFR: 1.90 ± 0.50 in Group 3), whereas rest MBF (mL min-1 g-1) increased (MBF: 1.05 ± 0.42 in Group 1, 1.27 ± 0.56 in Group 2, and 1.41 ± 0.61 in Group 3). After adjusting for covariates, compared with Group 1, the odds ratios for impaired MFR (defined as MFR < 2.5) were 3.57 (95% CI: 2.32-5.48) for Group 2 and 34.9 (95% CI: 13.23-92.14) for Group 3. The results would be similar if only regional MFR were assessed. The risk prediction for CMD using SA was acceptable, with an AUC of 0.76. CONCLUSION: Low SA concentration was associated with the severity of CMD in both global and regional MFR as well as MBF.

Patient-tailored risk assessment of obstructive coronary artery disease using Rubidium-82 PET-based myocardial flow quantification with visual interpretation.

INTRODUCTION: Our aim was to estimate the probability of obstructive CAD (oCAD) for an individual patient as a function of the myocardial flow reserve (MFR) measured with Rubidium-82 (Rb-82) PET in patients with a visually normal or abnormal scan. MATERIALS AND METHODS: We included 1519 consecutive patients without a prior history of CAD referred for rest-stress Rb-82 PET/CT. All images were visually assessed by two experts and classified as normal or abnormal. We estimated the probability of oCAD for visually normal scans and scans with small (5%-10%) or larger defects (> 10%) as function of MFR. The primary endpoint was oCAD on invasive coronary angiography, when available. RESULTS: 1259 scans were classified as normal, 136 with a small defect and 136 with a larger defect. For the normal scans, the probability of oCAD increased exponentially from 1% to 10% when segmental MFR decreased from 2.1 to 1.3. For scans with small defects, the probability increased from 13% to 40% and for larger defects from 45% to > 70% when segmental MFR decreased from 2.1 to 0.7. CONCLUSION: Patients with > 10% risk of oCAD can be distinguished from patients with < 10% risk based on visual PET interpretation only. However, there is a strong dependence of MFR on patient's individual risk of oCAD. Hence, combining both visual interpretation and MFR results in a better individual risk assessment which may impact treatment strategy.

Change Point Detection for Fine-Grained MFR Work Modes with Multi-Head Attention-Based Bi-LSTM Network.

Detection of the changes in Multi-Functional Radar (MFR) work modes is a critical situation assessment task for Electronic Support Measure (ESM) systems. There are two major challenges that must be addressed: (i) The received radar pulse stream may contain multiple work mode segments of unknown number and duration, which makes the Change Point Detection (CPD) difficult. (ii) Modern MFRs can produce a variety of parameter-level (fine-grained) work modes with complex and flexible patterns, which are challenging to detect through traditional statistical methods and basic learning models. To address the challenges, a deep learning framework is proposed for fine-grained work mode CPD in this paper. First, the fine-grained MFR work mode model is established. Then, a multi-head attention-based bi-directional long short-term memory network is introduced to abstract high-order relationships between successive pulses. Finally, temporal features are adopted to predict the probability of each pulse being a change point. The framework further improves the label configuration and the loss function of training to mitigate the label sparsity problem effectively. The simulation results showed that compared with existing methods, the proposed framework effectively improves the CPD performance at parameter-level. Moreover, the F1-score was increased by 4.15% under hybrid non-ideal conditions.

Post COVID-19 syndrome with impairment of flow-mediated epicardial vasodilation and flow reserve.

AIMS: The aim of this study is to evaluate whether post-acute sequelae of COVID-19 cardiovascular syndrome (PASC-CVS) is associated with alterations in coronary circulatory function. MATERIALS AND METHODS: In individuals with PASC-CVS but without known cardiovascular risk factors (n = 23) and in healthy controls (CON, n = 23), myocardial blood flow (MBF) was assessed with 13 N-ammonia and PET/CT in mL/g/min during regadenoson-stimulated hyperemia, at rest, and the global myocardial flow reserve (MFR) was calculated. MBF was also measured in the mid and mid-distal myocardium of the left ventricle (LV). The Δ longitudinal MBF gradient (hyperemia minus rest) as a reflection of an impairment of flow-mediated epicardial vasodilation, was calculated. RESULTS: Resting MBF was significantly higher in PASC-CVS than in CON (1.29 ± 0.27 vs. 1.08 ± 0.20 ml/g/min, p ≤ .024), while hyperemic MBFs did not differ significantly among groups (2.46 ± 0.53 and 2.40 ± 0.34 ml/g/min, p = .621). The MFR was significantly less in PASC-CVS than in CON (1.97 ± 0.54 vs. 2.27 ± 0.43, p ≤ .031). In addition, there was a Δ longitudinal MBF gradient in PASC-CVS, not observed in CON (-0.17 ± 0.18 vs. 0.04 ± 0.11 ml/g/min, p < .0001). CONCLUSIONS: Post-acute sequelae of COVID-19 cardiovascular syndrome may be associated with an impairment of flow-mediated epicardial vasodilation, while reductions in coronary vasodilator capacity appear predominantly related to increases in resting flow in women deserving further investigations.

PFOS Mass Flux Reduction/Mass Removal: Impacts of a Lower-Permeability Sand Lens within Otherwise Homogeneous Systems.

Perfluorooctane sulfonic acid (PFOS) is one of the most common per- and polyfluoroalkyl substances (PFAS) and is a significant risk driver for these emerging contaminants of concern. A series of two-dimensional flow cell experiments was conducted to investigate the impact of flow field heterogeneity on the transport, attenuation, and mass removal of PFOS. A simplified model heterogeneous system was employed consisting of a lower-permeability fine sand lens placed within a higher-permeability coarse sand matrix. Three nonreactive tracers with different aqueous diffusion coefficients, sodium chloride, pentafluorobenzoic acid, and ß-cyclodextrin, were used to characterize the influence of diffusive mass transfer on transport and for comparison to PFOS results. The results confirm that the attenuation and subsequent mass removal of the nonreactive tracers and PFOS were influenced by mass transfer between the hydraulically less accessible zone and the coarser matrix (i.e., back diffusion). A mathematical model was used to simulate flow and transport, with the values for all input parameters determined independently. The model predictions provided good matches to the measured breakthrough curves, as well as to plots of reductions in mass flux as a function of mass removed. These results reveal the importance of molecular diffusion and pore water velocity variability even for systems with relatively minor hydraulic conductivity heterogeneity. The impacts of the diffusive mass transfer limitation were quantified using an empirical function relating reductions in contaminant mass flux (MFR) to mass removal (MR). Multi-step regression was used to quantify the nonlinear, multi-stage MFR/MR behavior observed for the heterogeneous experiments. The MFR/MR function adequately reproduced the measured data, which suggests that the MFR/MR approach can be used to evaluate PFOS removal from heterogeneous media.

Theoretical exploration of the mechanism of formylmethanofuran dehydrogenase: the first reductive step in CO2 fixation by methanogens.

A theoretical exploration of the possible active site models of methanofuran dehydrogenase reveals that the free energy of the reduction of the carbamate group is substantially negative and is driven by the electron withdrawing amide group next to the carbonyl carbon. Comparison of the computed transition state energies with the experimental energy barrier indicates that the active site is likely to have an axial oxo and equatorial hydrosulfide ligand, the substrate is likely to be protonated and a second-sphere hydrogen-bonding interaction with the axial ligand can, substantially, lower the barrier of this reaction which involves reduction of the carbonyl center of the a carbamate to form an N-formyl group via a hydride shift from a Mo(IV) center.

Anthropometric and craniofacial sexual dimorphism in obstructive sleep apnea patients: is there male-female phenotypical convergence?

Obstructive sleep apnea (OSA) is more common in men than women. Body size is greater in males (sexual dimorphism), but large body habitus is associated with OSA for both genders. We speculated that male-female phenotypical convergence (reduced sexual dimorphism via identical phenotype acquisition) occurs with OSA and tested hypotheses: (1) phenotypical features pathogenic for OSA differ between OSA and healthy subjects irrespective of gender; and (2) such characteristics exhibit phenotypical convergence. Utilizing an existing database, we calculated male-female (group average) ratios for eight anthropometric and 33 surface cephalometric variables from 104 Caucasian OSA patients [72 males; apnea-hypopnea index (events h(-1) ): males: 42.3 ± 24.7 versus females: 42.6 ± 26.1 (P > 0.9)] and 85 Caucasian, healthy, non-OSA, community volunteers (36 males). Log-transformed data were analysed using a general linear model with post-hoc unpaired t-tests and significance at P < 0.0012 (Bonferroni multiple-comparison correction). OSA patients were older (56.9 ± 14.4 versus 38.0 ± 13.8 years), but there were no within-group gender-based age differences. All anthropometric variables (except height), plus cranial base width, mandibular breadth and retromandibular width diagonal were larger in gender-matched OSA versus healthy comparisons; thus satisfying hypothesis (1). Male-female ratios were mostly >1.0 across groups, but with no significant group × gender interactions no variable satisfied hypothesis (2). Thus, in this exploratory study, OSA patients had gender-common phenotypical differences to healthy subjects, but sexual dimorphism was preserved. Lack of complete phenotypical convergence may indicate gender-based critical phenotype-level attainment for OSA and/or gender-based OSA prevalence arises from factors other than those in this study.

Impact of time-of-flight on qualitative and quantitative analyses of myocardial perfusion PET studies using (13)N-ammonia.

BACKGROUND: The impact of time-of-flight (TOF) in myocardial perfusion (13)N-ammonia positron emission tomography (PET) is unclear. METHODS AND RESULTS: Twenty consecutive subjects underwent rest and adenosine stress (13)N-ammonia myocardial perfusion PET. Two sets of images were reconstructed using TOF-ordered subset expectation maximization (TOF-OSEM) and 3-dimensional row-action maximum likelihood algorithm (3D-RAMLA). Qualitative and quantitative analyses from the TOF-OSEM and 3D-RAMLA reconstructions were compared. Count profile curves revealed that TOF relatively increased the uptake of (13)N-ammonia at the lateral walls, and apical thinning was emphasized on the TOF images. Both segmental rest and stress myocardial blood flow (MBF) values were higher with TOF-OSEM use than with 3D-RAMLA use (rest MBF: 0.955 ± 0.201 vs 0.836 ± 0.185, P < .001; stress MBF: 2.149 ± 0.697 vs 2.058 ± 0.721, P < .001). The differentiation of MBF between reconstructions was more enhanced under rest conditions. Thus, segmental myocardial flow reserve (MFR) observed using TOF-OSEM reconstruction was lower than that observed using 3D-RAMLA (2.25 ± 0.57 vs 2.46 ± 0.75, P < .001). No remarkable differences were observed between segmental and territorial results. CONCLUSIONS: TOF increased lateral wall counts and emphasized apical thinning. Quantitatively, TOF reconstruction showed increased MBF, especially under relatively low perfusion conditions.

Protective effect of Monascus fermented rice against STZ-induced diabetic oxidative stress in kidney of rats.

In the present study, anti-diabetic activity and nephroprotective effect of MMFR was evaluated by using STZ-induced diabetic rats. Administration of MMFR at 100 and 200 mg/kg bw showed significant (P < 0.01) anti-hyperglycemic activity by lowering blood glucose level, HbA1C and increasing body weight. Altered lipid profiles in diabetic rats were restored to normal level on treatment with MMFR and showed significant (P < 0.01) decrease in the elevated levels of biochemical parameters. MMFR produced significant (P < 0.01) improvement in antioxidant levels in kidney. Food safety of MFR produced by using mutant Monascus purpureus 254 (MMFR) was evaluated for genotoxicity and oral acute toxicity. In Ames mutagenicity assay MMFR doesn't showed any toxicity to the test strain S. typhimurium till 5 mg/plate. Acute toxicity study also recorded no toxicity till the dose of 5,000 mg/kg bw. The study concluded that MMFR, not only possess anti-diabetic activity but also prevents nephropathy and hypercholesterolemia due to diabetes.

PET/CT Assessment of Flow-Mediated Epicardial Vasodilation in Obesity and Severe Obesity.

Background: It is not known whether the transition from obesity and severe obesity, as 2 different metabolic disease entities, affect flow-mediated and, thus, endothelium-dependent epicardial vasodilation. Objectives: The purpose of this study was to investigate the effect of obesity and severe obesity on flow-mediated epicardial vasomotion with positron emission tomography/computed tomography-determined longitudinal decrease in myocardial blood flow (MBF) from the base-to-apex direction of the left ventricle or gradient. Methods: 13N-ammonia positron emission tomography/computed tomography evaluated global MBF during pharmacologically induced hyperemia and at rest for assessment of coronary microvascular function. In addition, the Δ longitudinal MBF gradient (hyperemia minus rest) was determined. Patients were then grouped according to the body mass index (BMI) into normal weight (NW) (BMI 20.0-24.9 kg/m2, n = 27), overweight (OW) (BMI 25.0-29.9 kg/m2, n = 29), obesity (OB) (BMI 30.0-39.9 kg/m2, n = 53), and severe obesity (morbid obesity: BMI ≥40 kg/m2, n = 43). Results: Compared to NW, left ventricular Δ longitudinal MBF gradient progressively declined in OW and OB (0.04 ± 0.09 mL/g/min vs -0.11 ± 0.14 mL/g/min and -0.15 ± 0.11 mL/g/min; P ≤ 0.001, respectively) but not significantly in SOB (-0.01 ± 0.11 mL/g/min, P = 0.066). Regadenoson-induced global hyperemic MBF was lower in OB than in NW (1.88 ± 0.40 mL/g/min vs 2.35 ± 0.32 mL/g/min; P ≤ 0.001), while comparable between NW and SOB (2.35 ± 0.32 mL/g/min vs 2.26 ± 0.40 mL/g/min; P = 0.302). The BMI of the study population was associated with the Δ longitudinal MBF gradient in a U-turn fashion (r = 0.362, standard error of the estimate = 0.124; P < 0.001). Conclusions: Increased body weight associates with abnormalities in coronary circulatory function that advances from an impairment flow-mediated, epicardial vasodilation in overweight and obesity to coronary microvascular dysfunction in obesity, not observed in severe obesity. The U-turn of flow-mediated epicardial vasomotion outlines obesity and severe obesity to affect epicardial endothelial function differently.

Body composition, metabolic syndrome, and lifestyle in treatment-naïve gender-diverse youth in Israel.

BACKGROUND: There is a scarcity of published studies evaluating transgender/gender-diverse youth before initiating gender-affirming hormones. AIM: To study the body composition, metabolic syndrome (MetS) components and lifestyle habits in treatment-naïve transgender youth. METHODS: Cross-sectional study evaluating 153 transgender youth [median age 15.7 years, 94 transgender males] who attended The Israeli Children and Adolescents Gender Clinic between 6/2021-12/2022. Clinical, metabolic data and lifestyle habits (diet, physical activity and sleep patterns) were retrieved from the medical files. Body composition was determined by bioelectrical impedance analysis. Body mass index and muscle-to-fat ratio z-scores were calculated by sex designated at birth. RESULTS: Weight categories differed between genders, with a greater proportion of subjects classified as underweight among transgender females, and a greater proportion affected by overweight/obese/severe obese among transgender males (p = 0.035). The odds for MetS components were increased by 2.2 for every 1 standard deviation decrease in the muscle-to-fat ratio z-score (95%CI: 1.45 to 3.26, p < 0.001). About one-third of the cohort did not meet any of the three lifestyle recommendations. Transgender males had increased odds for MetS components by 3.49 (95%CI: 1.63 to 7.44, p = 0.001). CONCLUSIONS: Treatment-naïve transgender-male adolescents have an imbalance between muscle and adipose tissue, which places them at increased susceptibility for MetS components even prior to hormonal treatment.

Body Composition and Metabolic Syndrome Components in Transgender/Gender Diverse Adolescents and Young Adults.

Purpose: The objective of this study was to examine the association of designated sex at birth, body composition, and gender-affirming hormone treatment (GAHT) with the components of metabolic syndrome (MetS) (overweight/obesity, elevated blood pressure [BP], altered glucose metabolism, and dyslipidemia) in transgender/gender diverse (TGD) adolescents and young adults. Methods: TGD individuals underwent body composition studies by bioelectrical impedance analysis according to designated sex at birth, and their muscle-to-fat ratio (MFR) z-scores were calculated. Generalized estimating equations with binary logistic models (n = 326) were used to explore associations while adjusting for potential confounders. Results: A total of 55 TGD females and 111 TGD males, with mean age of 18 ± 1.9 years and median duration of GAHT of 1.4 years (interquartile range = 0.6-2.5), were enrolled. Overall, 118/166 (71%) of the TGD cohort showed evidence of at least one MetS component, with a significantly higher rate among TGD males compared with TGD females (91.1% vs. 50.9%, p < 0.001). TGD males were at increased odds for overweight/obesity, elevated/hypertensive BP, elevated triglycerides (TGs), and an atherogenic dyslipidemia index (TG/high-density lipoprotein cholesterol [HDL-c], TG:HDL-c). The odds of overweight/obesity increased by 44.9 for each standard deviation decrease in the MFR z-score, while the odds for an elevated TG:HDL-c index increased by 3.7. Psychiatric morbidity increased the odds for overweight/obesity by 2.89. Conclusions: After considering confounding variables, the TGD males on GAHT were found to be at an increased risk for cardiometabolic disease. Our observations support the importance of targeted medical nutrition intervention in this group of individuals.

Coronary microvascular dysfunction and myocardial area at risk assessed by cadmium zinc telluride single photon emission computed tomography after primary percutaneous coronary intervention in acute myocardial infarction patients.

Background: A high proportion of coronary microvascular dysfunction (CMD) has been observed in patients with acute myocardial infarction (AMI) who have received primary percutaneous coronary intervention (PCI), which may affect their prognosis. This study used cadmium zinc telluride (CZT) single photon emission computed tomography (SPECT) to evaluate the prevalence and characteristics of CMD and myocardial area at risk (AAR) in AMI patients who had undergone primary PCI. Methods: We conducted a single-center cross-sectional retrospective study at TEDA International Cardiovascular Hospital from September 2021 to June 2022. A total of 83 patients received primary PCI for AMI. Subsequently, a rest/stress dynamic and routine gated myocardial perfusion imaging (MPI) were performed 1 week after PCI. The CMD group was defined as having a residual stenosis of infarct-related artery (IRA) <50% and myocardial flow reserve (MFR) <2.0 in this corresponding territory, whereas MFR ≥2.0 of IRA pertained to the normal control group. Rest-AAR of infarction (%) and stress-AAR (%) were expressed by the percentage of measured rest-defect-size and stress-defect-size in the left ventricular area, respectively. Logistic regression analyses were performed to identify significant predictors of CMD. Results: A total of 53 patients with a mean age of 57.06±11.99 years were recruited, of whom 81.1% were ST-segment elevation myocardial infarction (STEMI). The proportion of patients with CMD was 79.2% (42/53). The time of pain to SPECT imaging was 7.50±1.27 days in the CMD group and 7.45±1.86 days among controls. CMD patients had a higher body mass index (BMI) than controls (26.48±3.26 vs. 24.36±2.73 kg/m2, P=0.053), and a higher proportion of STEMI, thrombolysis in myocardial infarction (TIMI) 0 grade of IRA prior PCI than controls (88.1% vs. 54.5%, P=0.011; 61.9% vs. 18.2%, P=0.004, respectively). No significant difference was identified in the rest-myocardial blood flow (MBF) of IRA between the 2 groups, whereas the stress-MBF and MFR of IRA, rest-AAR, and stress-AAR in the CMD group were remarkably lowered. Higher BMI [odds ratio (OR): 1.332, 95% confidence interval (CI): 1.008-1.760, P=0.044] and stress-AAR (OR: 1.994, 95% CI: 1.122-3.543, P=0.019) were used as independent predictors of CMD occurrence. Conclusions: The prevalence of CMD is high in AMI patients who received primary PCI. Each 1 kg/m2 increase in BMI was associated with a 1.3-fold increase in CMD risk. A 5% increase in stress-AAR was associated with a nearly 2-fold increase in CMD risk. Increased BMI and stress-AAR predicts decreased coronary reserve function.

Incremental prognostic value of digital positron emission tomography derived myocardial flow reserve: A prospective cohort study.

BACKGROUND: Positron Emission Tomography (PET) Myocardial Perfusion Imaging (MPI) is a robust diagnostic and prognostic test in patients with suspected or known coronary artery disease (CAD). We aimed to assess the incremental prognostic value of myocardial flow reserve (MFR) using the latest generation of digital PET scanners. METHODS: Consecutive patients with clinically indicated PET MPI for suspected or known CAD were included. Myocardial blood flow (MBF) in ml/min/g was obtained from dynamic images at rest and peak hyperemia, and the myocardial flow reserve (MFR) was calculated as the ratio of stress to rest MBF. Patients were followed from the date of PET imaging for the occurrence of the primary outcome (composite of all-cause death, myocardial infarction, and Percutaneous Coronary Intervention or Coronary Artery Bypass Graft occurring >90 days after imaging). Nested multivariable Cox regression models were used to assess the incremental prognostic role of MFR over traditional risk factors and PET relative perfusion parameters. RESULTS: The final cohort consisted of 3534 patients (mean age 67 ± 12 years, 48% female, 67% Caucasian, 53% obese, 55% hypertension, 32% diabetes, 42% dyslipidemia). During a median follow-up of 8.5 (3.0-15.4) months, 229 patients (6.5%, 6.4 per 1000 person-years) experienced the primary outcome. In nested multivariable Cox models, impaired MFR (MFR < 2) was significantly associated with the primary outcome (HR 2.9, 95% CI 2.0-4.1, p < 0.001) and significantly improved discrimination (Harrell's C 0.77, p = 0.002). CONCLUSION: MFR derived from digital PET scanners has an independent and incremental prognostic role in patients with suspected or known CAD.

Shin Splint: A Review.

Medial tibial stress syndrome (MTSS), usually referred to as "shin splints," is a common overuse injury of the lower extremities affecting a large percentage of athletes. A variety of factors can lead to shin splints, including overtraining, poor footwear, muscular imbalances at the ankle, overtight or weak triceps surae muscles, imbalances at the thoracolumbar complex, and a body mass index (BMI) above 30. Injuries present with diffuse palpable pain that is often described as a dull ache following exercise. The pain is often alleviated by resting. Often, athletes complain of tenderness along the posteromedial edge of the tibia and pain along the middle to distal third of the posteromedial border of the tibia following an exercise session. The pain caused by a shin splint should be categorized according to its location and cause, such as lower medial tibial pain caused by periostitis or upper lateral tibial pain caused by raised compartment pressure. In order to prevent MTSS or shin splints, it is important to avoid excessive stress. The main objectives of shin splint treatment are to relieve pain and to enable the patient to return to normal activities without pain. To prevent shin splints, repetitive stress should be avoided. In this paper, we review what is known about the pathophysiology of shin splint syndrome, present evidence regarding risk factors associated with shin splints, assess the effectiveness of prevention strategies, and make recommendations for prevention. The purpose of this study is to assess the effectiveness of interventions to prevent shin splints.

Clinical and histological evaluation of microneedle fractional radiofrequency treatment on facial fine lines and skin laxity in Koreans.

BACKGROUND: Facial wrinkles and sagging are the most visible signs of aging and can cause profound distress. Microneedle fractional radiofrequency (MFR) is a minimally invasive procedure, which utilizes both microneedling and radiofrequency energy to rejuvenate the skin. OBJECTIVE: To describe the safety and efficacy of a temperature-controlled MFR device on facial fine lines and laxity. PATIENTS AND METHODS: A retrospective chart & histology review was performed on individuals who received bipolar MFR for facial rejuvenation. A total of 15 Koreans with a median age of 46 years were included. All participants underwent a single treatment session. The results were assessed objectively using serial photography and subjectively based on the participants' satisfaction scores. Histologic changes before, immediately after MFR and at 4 months follow-up was examined. Complications were also recorded. RESULTS: Partially denatured collagen fibers and dermal shrinkage was observed immediately after MFR whereas an increase in elastin and collagen was noted at 4 months follow-up. 86.7% of recipients considered the results satisfactory. Consensus ratings by two independent dermatologists on the objective outcomes at 4-month follow-up were very much improved (53.3%), much improved (26.7%) and improved (20%). Treatment was well tolerated and did not cause any significant long-lasting discomfort. CONCLUSION: Temperature-controlled bipolar MFR is a minimally invasive treatment option to consider for facial fine lines and laxity via neo-collagenesis and neo-elastogenesis. The procedure was safe and clinically effective.

Comparison of Structural Diagnosis and Management (SDM) approach and MyoFascial Release (MFR) for improving plantar heel pain, ankle range of motion and disability: A randomized clinical trial.

[Purpose] The purpose of this study was to compare the effectiveness of the Structural Diagnosis and Management (SDM) approach with Myofascial Release (MFR) in improving plantar heel pain, ankle range of motion, and disability. [Subjects] Sixty-four subjects, aged 30-60 years, with a diagnosis of plantar heel pain, plantar fasciitis, or calcaneal spur by a physician according to ICD-10, were equally allocated to the MFR (n = 32) and SDM (n = 32) groups by hospital randomization and concealed allocation. [Methods] In this assessor-blinded randomized clinical trial, the control group performed MFR to the plantar surface of the foot, triceps surae, and deep posterior compartment calf muscles, while the experimental group performed a multimodal approach utilizing the SDM concept for 12 sessions over 4 weeks. Both groups also received strengthening exercises, ice compression, and ultrasound therapy. Pain, activity limitations and disability were assessed as primary outcomes using the Foot Function Index (FFI) and Range of motion (ROM) assessment of the ankle dorsiflexors and plantar flexors using a universal goniometer. Secondary outcomes were measured using the Foot Ankle Disability Index (FADI) and a 10-point manual muscle testing process for the ankle dorsiflexors and plantar flexors. [Results] Both MFR and SDM groups exhibited significant improvements from baseline in all outcome variables, including pain, activity level, disability, range of motion, and function after the 12-week intervention period (p < .05). The SDM group showed more improvements than MFR for FFI pain (p < .01), FFI activity (p < .01), FFI (p < .01) and FADI (p = <.01). [Conclusion] Both MFR and SDM approaches are effective in reducing pain, improving function, ankle range of motion, and reducing disability in plantar heel pain, however, the SDM approach may be a preferred treatment option.

Simultaneous Modification of Properties Relevant to the Processing and Application of Virgin and Post-Consumer Polypropylene.

Post-consumer recyclates often have a property profile that results from mixing a variety of products, which are made from different materials, produced by different processing methods, and coming from applications with different lifetimes. This usually leads to a mixture of all these material properties in the recycling process. In contrast, virgin materials are specifically designed for applications and thus offer all the necessary properties for the intended products. In order to be able to use recycled materials for specific and demanding applications, not only the viscosity, which is important for processing and often varies greatly with recyclates, but also the mechanical properties, particularly the tensile modulus and impact strength, must be adjusted. For this purpose, various virgin materials of polypropylene homopolymers, random copolymers, and block copolymers with different flowabilities were mixed in different proportions and their properties were determined. The flowability of homopolymers and random copolymers in the blend behaved very similarly, while block copolymers exhibited a different behavior in some cases. By incorporating homopolymers into blends, the stiffness of the resulting material blend can be very well adjusted. The addition of random copolymers can increase strain at break, and the addition of block copolymers results in a significant increase in impact strength. In numbers, the maximum adjustment range for tensile modulus, yield stress, strain at break, and impact strength are 880 MPa, 14 MPa, 185%, and 6.9 kJ/m2, respectively. While a good and reliable prediction of property profile is possible for polymer blends with different virgin materials, the resulting material properties for polymer blends of virgin and recycled materials are also influenced by impurities. In this work, however, a good prediction was also achieved for recyclate blends.

Improved precision of SPECT myocardial blood flow using a net tracer retention model.

BACKGROUND: Noninvasive quantification of absolute myocardial blood flow (MBF) and myocardial flow reserve (MFR) provides incremental benefit to relative myocardial perfusion imaging (MPI) to diagnose and manage heart disease. MBF can be measured with single-photon emission computed tomography (SPECT) but the uncertainty in the measured values is high. Standardization and optimization of protocols for SPECT MBF measurements will improve the consistency of this technique. One element of the processing protocol is the choice of kinetic model used to analyze the dynamic image series. PURPOSE: This study evaluates if a net tracer retention model (RET) will provide a better fit to the acquired data and greater test-retest precision than a one-compartment model (1CM) for SPECT MBF, with (+MC) and without (-MC) manual motion correction. METHODS: Data from previously acquired rest-stress MBF studies (31 SPECT-PET and 30 SPECT-SPECT) were reprocessed ± MC. Rate constants (K1) were extracted using 1CM and RET, +/-MC, and compared pairwise with standard PET MBF measurements using cross-validation to obtain calibration parameters for converting SPECT rate constants to MBF and to assess the goodness-of-fit of the calibration curves. Precision (coefficient of variation of test re-test relative differences, COV) of flow measurements was computed for 1CM and RET ± MC using data from the repeated SPECT MBF studies. RESULTS: Both the RET model and MC improved the goodness-of-fit of the SPECT MBF calibration curves to PET. All models produced minimal bias compared with PET (mean bias < 0.6%). The SPECT-SPECT MBF COV significantly improved from 34% (1CM+MC) to 28% (RET+MC, P = 0.008). CONCLUSION: The RET+MC model provides a better calibration of SPECT to PET and blood flow measurements with better precision than the 1CM, without loss of accuracy.

Application of Mixing Rules for Adjusting the Flowability of Virgin and Post-Consumer Polypropylene as an Approach for Design from Recycling.

To enable the use of recyclates in thermoformed polypropylene products with acceptable optical appearance and good mechanical stability, a multilayer structure of virgin and recycled material can be used. When producing multilayer films with more than two layers, the used materials should have similar melt flow properties to prevent processing instabilities. In the case of a three-layer film, post-consumer recyclates are often hidden in the core layer. Due to the inconsistent melt flow properties of post-consumer recyclates, the adjustment of the melt flow properties of the core layer to those of the outer layers has to be realized by blending with virgin materials. In order to understand the effect of mixing with a virgin material with a certain pre-defined melt flow rate (MFR), material mixtures with different mixing partners from various sources were realized in this study. Hence, the pre-defined virgin material was mixed with (i) virgin materials, (ii) artificial recyclates out of a mixture of different virgin materials, and (iii) commercially available recyclates. These blends with mixing partner contents ranging from 0-100% in 10% increments were prepared by compounding and the MFR of each mixture was determined. For a mathematical description of the mixing behavior and furthermore for a proper MFR prediction of the material mix, existing mixing rules were tested on the three pre-defined sample groups. Therefore, this paper shows the applicability of different mixing rules for the prediction of the MFR of material blends. Furthermore, a new mixing rule was developed using symbolic regression based on genetic programming, which proved to be the most accurate predictive model.