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Clostridium septicum is an anaerobic, motile, spore-forming, toxin-producing gram-positive bacillus that can lead to rapidly progressive gas gangrene due to the release of alpha toxin. Aortic aneurysm secondary to C. septicum infection is a rare condition with 60 cases reported in the literature; however, we have recently treated several patients with the condition in our large tertiary care and aortic center. Blood and tissue culture results collected between January 2005 and January 2018 and maintained in the microbiology laboratory database at the Cleveland Clinic were reviewed to identify those with C. septicum reported. Each was reviewed to determine radiographic or histopathologic correlation with aortic disease. Seven cases of C. septicum aortitis were reviewed. Underlying malignant disease was found in four cases and a history of remote malignant disease in one case. The most common location for infection was the infrarenal abdominal aorta. Vascular surgery had previously been performed in three of the cases. Five of the seven patients underwent operative repair. All patients were treated with β-lactam antibiotics. The two patients who did not undergo an operation died, which is consistent with the 100% mortality described in the literature. Of the five patients who underwent an operation, there was only one documented survivor and one was lost to follow-up. In the largest reported case series, only a small percentage of patients with C. septicum -infected aortic aneurysms survived >1 year. In the patients described, those who did not receive an operation had 100% mortality. Earlier recognition and prompt operation with appropriate antimicrobial therapy are needed to improve the outcome of patients diagnosed with this rare infection. [ABSTRACT FROM AUTHOR]

Histotripsy thrombolysis is a non-invasive, drug-free, image-guided therapy that fractionates blood clots using well-controlled acoustic cavitation alone. Real-time quantitative feedback is highly desired during histotripsy thrombolysis treatment to monitor the progress of clot fractionation. Bubble-induced color Doppler (BCD) monitors the motion after cavitation generated by each histotripsy pulse, which has been found in gel and ex vivo liver tissue to be correlated with histotripsy fractionation. We investigated the potential of BCD to quantitatively monitor histotripsy thrombolysis in real time. To visualize clot fractionation, transparent three-layered fibrin clots were developed. Results indicated that a coherent motion follows the cavitation generated by each histotripsy pulse with a push and rebound pattern. The temporal profile of this motion expands and saturates as treatment progresses. A strong correlation exists between the degree of histotripsy clot fractionation and two metrics extracted from BCD: time of peak rebound velocity ( t PRV ) and focal mean velocity at a fixed delay ( V f,delay ). The saturation of clot fractionation ( i.e ., treatment completion) matches well the saturations detected using t PRV and V f,delay . The mean Pearson correlation coefficients between the progression of clot fractionation and the two BCD metrics were 93.1% and 92.6%, respectively. To validate BCD feedback in in vitro clots, debris volumes from histotripsy thrombolysis were obtained at different therapy doses and compared with V f,delay . There is also good agreement between the increasing and saturation trends of debris volume and V f,delay . Finally, a real-time BCD feedback algorithm to predict complete clot fractionation during histotripsy thrombolysis was developed and tested. This work illustrates the potential of BCD to monitor histotripsy thrombolysis treatment in real time. [ABSTRACT FROM AUTHOR]

Abstract: Histotripsy has shown promise in non-invasive cardiac therapy for neonatal and fetal applications. However, for cardiac applications in general, and especially in the adult heart, cardiac and respiratory motion may affect treatment accuracy and efficacy. In this article, we describe a histotripsy-mediated cardiac therapy system integrated with a fast motion tracking algorithm and treatment monitoring using ultrasound imaging. Motion tracking is performed by diamond search block matching in real-time ultrasound images using a reference image of the moving target, refined by Kalman filtering. As proof of feasibility, this algorithm was configured to track 2-D target motion and then electronically adjust the focus of a 1-MHz annular therapy array to correct for axial motion. This integrated motion tracking system is capable of sub-millimeter accuracy for displacements of 0–15 mm and velocities of 0–80 mm/s, with a maximum error less than 3 mm. Tissue phantom tests indicated that treatment efficiency and lesion size using motion tracking over displacements of 0–15 mm and velocities of 0–42 mm/s are comparable to those achieved when treating stationary targets. In vivo validation was conducted in an open-chest canine model, where the system provided 24 min of motion-corrected histotripsy therapy in the live beating heart, generating a targeted lesion on the atrial septum. Based on this proof of feasibility and the natural extension of these techniques to three dimensions, we anticipate a full motion correction system would be feasible and beneficial for non-invasive cardiac therapy. [Copyright &y& Elsevier]

Abstract: The flow of concentrated suspensions is well known to be accompanied by irreversible bulk migrations. One approach to modeling the migration of particles relative to the bulk motion is based on a particle flux induced by spatial variation of the particle normal stresses. A frame-invariant formulation of the mixture stresses is presented in a general form and used in this approach; specific forms of the constitutive model for the stress are considered. These forms either include only the isotropic shear-induced particle stress (particle pressure) or include both normal stress differences and the particle pressure. The predicted flow and migration behavior are considered for complex geometries, using the flows in a contraction and an expansion as the primary examples. Results are limited to two-dimensional flows. [Copyright &y& Elsevier]

[Display omitted] • Some d 6 transition metal [M(DABF) 2 A 2 + complexes should prefer trans geometries. • Preferences for trans geometries trend with increasing ligand atom atomic number. • This conflicts with geometric predictions from the trans influence concept. • Energy decompositions suggest DFT exchange underlies the anomalous preferences. Computational studies of low spin d 6 cis– and trans– [M(DABF) 2 A 2 + complexes (M = Co, Rh, Ir; A = anionic ligand) employing multiple model chemistries find that cis geometries are preferred for complexes where the binding atom in A is high and/or to the left in the Periodic Table, while trans geometries are preferred for complexes where the binding atom is heavy or to the right of the Periodic Table. This holds despite the fact that consideration of the trans influence for the π-acceptor spectator DABF ligand suggest that all such complexes should prefer cis geometries. Energy decomposition analysis ties the phenomenon mostly to the degree of DFT exchange; that this benefits trans geometries more than cis geometries is thought to arise from the greater electronic symmetry of the former. This is supported by predictions for haloborane complexes [M(DABF) 2 (BX 2) 2 +. In contrast, [M(CO) 4 A 2 + complexes, containing better π-accepting CO spectator ligands (presumably higher in the trans influence series), are predicted to prefer cis geometries except for the halogen complexes [M(CO) 4 X 2 + (X = F, Cl, I), where no distinct preferences exist. [ABSTRACT FROM AUTHOR]

Achievement of 5–10% weight loss (WL) among older adults living with obesity considerably improves prognosis of health-related outcomes; however, concomitant declines in bone mineral density (BMD) limit overall benefit by increasing fracture risk. Declines in mechanical loading contribute to WL-associated BMD loss, with pilot data signaling the addition of external weight replacement (via weighted vest use) during intentional WL mitigates bone loss at weight bearing sites to a similar degree as resistance exercise training (RT). Definitive data in support of weighted vest use as a potential strategy to mitigate WL-associated bone loss in this population are needed. In the Incorporating Nutrition, Vests, Education, and Strength Training (INVEST) in Bone Health trial (NCT04076618), 192 older adults (60–85 years) who are overweight (BMI ≥ 27 kg/m2) with at least one obesity-related risk factor or obese (BMI = 30–40 kg/m2) will be randomly assigned to participate in one of three 12-month intervention groups: WL alone, WL + weighted vest use (WL + VEST), or WL + RT. The primary aim is to determine the effects of WL + VEST compared to WL alone and WL + RT on indicators of bone health and subsequent fracture risk. Determining effective, translatable strategies that minimize bone loss during intentional WL among older adults holds public health potential. The INVEST in Bone Health trial offers an innovative approach for increasing mechanical stress during intentional WL in the absence of RT. If successful, findings from this study will provide evidence in support of a scalable solution to minimize bone loss during intentional WL among older adults with obesity. [ABSTRACT FROM AUTHOR]

Low-load resistance exercise with blood flow restriction (LL BFR-RE) has been shown capable of improving neuromuscular parameters in several clinical populations, however, its tolerability and effects on individuals with multiple sclerosis (MS) remains unknown. To investigate the perceptual responses of individuals with MS to LL BFR-RE versus traditional high-load resistance exercise (HL-RE). Four men and eleven women diagnosed with relapsing-remitting MS randomly completed the following experimental trials: 1) LL BFR-RE four sets of 30–15–15–15 repetitions, at 20% of one-repetition maximum (1-RM) of leg-press (LP) and knee-extension (KE), with 50% of BFR, and a 1-min rest interval between sets; 2) HL-RE– four sets of 8–10 repetitions, at 70% 1-RM of LP and KE, with the same rest intervals. Ratings of perceived exertion (RPE) were measured after each set, pain was measured before and after sets, and delayed-onset muscle soreness (DOMS) was measured at 5, 30, 60 min, and 24-h post-exercise. HL-RE elicited significantly (p <0.05) greater RPE compared to LL BFR-RE during all sets. Additionally, there were no significant (p >0.05) differences between LL BFR-RE and HL-RE for pain immediately after all sets, although pain measured before sets were significantly (p <0.05) greater for LL BFR-RE. Finally, both protocols resulted in similar DOMS, however, it was significantly (p <0.05) elevated 24-h post-exercise compared to 1-h after for HL-RE but not for LL BFR-RE. Altogether, these data demonstrate that LL BFR-RE is well tolerated by individuals with MS, requires less muscular exertion than HL-RE, and does not cause exaggerated pain during exercise or elevated DOMS up to 24 h post-exercise. [ABSTRACT FROM AUTHOR]

The purpose of this investigation was to identify the influence that sex, training intensity, and frequency have on long-term resistance exercise (RE) outcomes in older adults. One-hundred eleven older adults (men: 41, women: 70) completed either: high-intensity RE 2d/week (HI-2D; n = 29), low-intensity RE 2d/week (LI-2D; n = 32), high-intensity RE 3d/week (HI-3D, n = 20), or low-intensity RE 3d/week (LI-3D, n = 30). HI protocols completed 3 sets of 8 repetitions with 80% one-repetition maximum (1-RM) while LI completed 3 sets of 16 repetitions with 40% 1-RM. Total and regional bone free lean body mass (BFLBM) were assessed via dual-energy x-ray absorptiometry and cross-sectional area (mCSA) of the rectus femoris. mCSA was the only muscle quantity parameter to increase (p = 0.043). Significant trial effects for upper body, lower body, and specific strength were observed (all p < 0.001). Significant sex × time interactions (p < 0.001) were observed for upper and lower body strength, however, men and women displayed similar increases in lower body (45.7 ± 29.6 vs 46.4 ± 34.9%), upper body (33.1 ± 21.0 vs 33.4 ± 24.7%), and specific strength (36.5 ± 28.5 vs 40.1 ± 28.7%). A group × time interaction for lower body strength indicated that at 20-weeks HI-2D and LI-3D displayed greater lower body strength than LI-2D (both p < 0.009), and at 40-weeks HI-2D, HI-3D, and LI-3D displayed significantly greater lower body strength than LI-2D (all p < 0.038). These observations indicate that older men and women display similar long-term RE outcomes. Additionally, regardless of frequency or intensity, the current prescriptions were effective for increasing strength, however these data suggest HI-2D > LI-2D and LI-3D > LI-2D but similar outcomes among HI-2D, HI-3D, and LI-3D. The variety of effective RE approaches provides flexibility among older adults for selecting a lifestyle intervention that would be most sustainable. • Long-term strength adaptations are similar between older men and women. • Strength increases were evident despite marginal changes for lean body mass. • HI-2D, HI-3D, and LI-3D had greater lower body strength than LI-2D post-intervention. • All training groups displayed similar upper body and specific strength post-intervention. [ABSTRACT FROM AUTHOR]

• Practical blood flow restriction exercise may provide a more favorable exercise condition when compared to clinical blood flow restriction exercise. • High intensity and clinical blood flow restriction induce greater perceptual responses than low intensity or practical blood flow restriction exercise. The purpose of the current investigation was to compare the acute perceptual responses during low-load resistance exercise (RE) with clinical blood flow restriction (cBFR-RE) and practical blood flow restriction (pBFR-RE), and during conventional low- (LL-RE) and high-load resistance exercise (HL-RE), to determine if these responses differed between young males and females. Twenty-nine participants (14 males: 23.6±2.7years, 25.3±3.1kg/m2 and 15 females: 20.3±1.6years, 23.4±1.9kg/m2) completed the following exercise conditions in a randomized design: 1) cBFR-RE, 2) pBFR-RE, 3) HL-RE, and 4) LL-RE. Low-load conditions consisted of 30-15-15-15 repetitions of two-leg press (LP) and knee extension (KE) exercises with 30% one-repetition maximum (1-RM), and HL-RE consisted of 3 sets of 10 repetitions at 80% 1-RM, all with 60s rest intervals. Ratings of perceived exertion (RPE) and discomfort were assessed before exercise and immediately following each set. RPE was significantly higher in HL-RE compared to all low-load conditions for both exercises after each set (all p<0.05). cBFR-RE resulted in significantly greater RPE than pBFR-RE and LL-RE for both exercises for sets 1-4 for LP and sets 2-3 for KE (all p<0.05). Levels of discomfort were similar between cBFR-RE and HL-RE, which tended to be significantly higher than pBFR-RE and LL-RE (p<0.05). Men reported significantly greater RPE than women following sets 2-4 during KE with cBFR-RE and sets 2 and 3 during KE for HL-RE (all p<0.05). Males also reported significantly greater discomfort than women following sets 2-4 for KE LL-RE (p<0.05). Altogether, these data suggest that pBFR-RE may provide a more favorable BFR condition based on perceptual responses and that perceptual responses may differ between sexes across varying resistance exercise conditions. [ABSTRACT FROM AUTHOR]

We investigated the perceptual responses to resistance exercise (RE) with continuous and intermittent blood flow restriction (BFR). Fourteen males randomly completed the following exercise conditions: low-load RE with continuous BFR (cBFR), low-load RE with intermittent BFR (iBFR), low-load RE without BFR (LI), and traditional high-load RE (HI). Participants completed 4 sets of 30-15-15-15 repetitions of bilateral leg press and knee extension exercises during the low-load conditions, at 20% of one-repetition maximum (1-RM), a 1.5‑sec metronome-controlled pace, with a 1-min rest interval between sets; HI consisted of 4 sets of 10 repetitions of the same exercises, at 70% 1-RM, with the same pace and rest interval. Ratings of perceived exertion (RPE) and discomfort were assessed using psychometric scales before exercise and after each set. RPE displayed no significant differences (p > 0.05) between the BFR conditions for either exercise. Additionally, both BFR conditions elicited significantly (p < 0.05) greater RPE than LI and significantly (p <0.05) lower RPE than HI during both exercises. Rating of discomfort displayed no significant differences between BFR conditions during the first two sets of leg press; however, cBFR evoked greater discomfort compared to iBFR during the last two sets. There were no significant (p > 0.05) differences observed between conditions during the knee extension exercise. Rating of discomfort was similar between the BFR and HI conditions and each were significantly greater than LI during both exercises. Therefore, cBFR and iBFR seem to produce similar perceptual responses, which are greater than LI and lower than HI, but similar in regards to discomfort. [ABSTRACT FROM AUTHOR]

The article presents information on a decade of progress in immunization information systems (IIS). IIS are confidential, computerized, population-based systems that collate, keep, and merge vaccination information from several parts of the health care system. The systems are U.S. state-based programs aimed at tracking the immunization status of individuals within a public health jurisdiction.