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Purpose: According to the side effects of invasive cancer treatments, Sonodynamic Therapy (SDT) as a noninvasive method for breast adenocarcinoma was considered. Sonosensitizer agents’ encapsulation can improve the accumulation of these drugs in the tumor tissue and reduce treatment side effects. Hence, mice breast adenocarcinoma SDT with Hematoporphyrin (HP) and HP-encapsulated Mesoporous Silica Nanoparticles (HP-MSNs) was carried out. Materials and Methods: 96 female breast adenocarcinoma grafted Balb/C mice were randomly divided into 16 groups (n = 6): control, sham, HP, HP-MSN, Ultrasound (US), SDT+HP, and SDT+HP-MSN groups. Sonosensitizer agents were injected intraperitoneally (2.5 or 5 mg/kg, 0.2 ml) 24h before an US radiation (1MHz, 1 or 2 W/cm2, 60 sec). The tumor growth parameters were evaluated 30 days after SDT. Results: The inhibition ratio was enhanced by 23, 18, 18, and 16% relative to the control group in HP-MSN (5 mg/kg), HP-MSN (2.5 mg/kg) HP (5 mg/kg) and US (2 W/cm2) groups, respectively, at 18 days after the injection time; whereas, the analysis of findings revealed an antitumor effect in SDT with HP-MSN groups. The Tumor Growth Inhibition (TGI) percentages were 45, 42, and 42% for the SDT (2 W/cm2) + HP-MSN (5 mg/kg), SDT (1 W/cm2) + HP-MSN (5 mg/kg), and SDT (2 W/cm2) + HP (2.5 mg/kg) groups, respectively, on the 18th day post-injection, and T2 and T5 times were higher than that of control and sham groups (P

Purpose: Numerous studies have described the effect of Electromagnetic Fields (EMFs) in the promotion of Bone Marrow Stem Cell (BMSC) differentiation. We aimed to investigate the influence of frequency (10 and 100 Hz) and different pulse shapes (sine, rectangular, and triangular) of EMF on rats' BMSCs. Materials and Methods: The BMSCs in 6 groups were exposed to EMF for 1 h/ 7 days. The BMSCs viability was estimated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. The cresyl violet labeled the Nissl bodies, and the silver nitrate staining was done to evaluate the BMSCs nucleoli AgNORs. Results: The MTT test verified that EMF and pulse shape did not affect cell viability. In Nissl bodies staining most of the large neurons were related to the rectangular 10 Hz EMF group. The majority of the differentiated BMSCs were astrocytes, microglia, and oligodendrocyte in the triangular 100 Hz EMF group. Although the silver nitrate staining confirmed the effect of 10 Hz EMF, pulse shape alteration did not affect AgNOR parameters. In conclusion, we presented a low-magnetic flux density EMF (400 µT) to assess the responses of BMSCs nuclei. Conclusion: The findings showed that BMSCs differentiation was frequency-dependent. Further investigations are recommended for recognizing the function of EMF on BMSCs.

Peripheral arterial disease differentially affects the superficial femoral (SFA) and the popliteal (PA) arteries, but their morphometric, structural, mechanical, and physiologic differences are poorly understood. SFAs and PAs from 125 human subjects (age 13–92, average 52±17 years) were compared in terms of radii, wall thickness, and opening angles. Structure and vascular disease were quantified using histology, mechanical properties were determined with planar biaxial extension, and constitutive modeling was used to calculate the physiologic stress-stretch state, elastic energy, and the circumferential physiologic stiffness. SFAs had larger radii than PAs, and both segments widened with age. Young SFAs were 5% thicker, but in old subjects the PAs were thicker. Circumferential (SFA: 96→193°, PA: 105→139°) and longitudinal (SFA: 139→306°, PA: 133→320°) opening angles increased with age in both segments. PAs were more diseased than SFAs and had 11% thicker intima. With age, intimal thickness increased 8.5-fold, but medial thickness remained unchanged (620μm) in both arteries. SFAs had 30% more elastin than the PAs, and their density decreased ~50% with age. SFAs were more compliant than PAs circumferentially, but there was no difference longitudinally. Physiologic circumferential stress and stiffness were 21% and 11% higher in the SFA than in the PA across all ages. The stored elastic energy decreased with age (SFA: 1.4→0.4kPa, PA: 2.5→0.3kPa). While the SFA and PA demonstrate appreciable differences, most of them are due to vascular disease. When pathology is the same, so are the mechanical properties, but not the physiologic characteristics that remain distinct due to geometrical differences.

Arterial mechanics plays an important role in vascular pathophysiology and repair, and advanced imaging can inform constitutive models of vascular behavior. We have measured the mechanical properties of 14 human superficial femoral arteries (SFAs) (age 12–70, mean 48±19 years) using planar biaxial extension, and determined the preferred collagen fiber direction and dispersion using multiphoton microscopy. The collagen fiber direction and dispersion were evaluated using second-harmonic generation imaging and modeled using bivariate von Mises distributions. The microstructures of elastin and collagen were assessed using two-photon fluorescence imaging and conventional bidirectional histology. The mechanical and structural data were used to describe the SFA mechanical behavior using two- and four-fiber family invariant-based constitutive models. Older SFAs were stiffer and mechanically more nonlinear than younger specimens. In the adventitia, collagen fibers were undulated and diagonally-oriented, while in the media, they were straight and circumferentially-oriented. The media was rich in collagen that surrounded the circumferentially-oriented smooth muscle cells, and the elastin was present primarily in the internal and external elastic laminae. Older SFAs had a more circumferential collagen fiber alignment, a decreased circumferential-radial fiber dispersion, but the same circumferential-longitudinal fiber dispersion as younger specimens. Both the two- and the four-fiber family constitutive models were able to capture the experimental data, and the fits were better for the four-fiber family formulation. Our data provide additional details on the SFA intramural structure and inform structurally-based constitutive models.

Poor outcomes of peripheral arterial disease stenting are often attributed to the inability of stents to accommodate the complex biomechanics of the flexed lower limb. Abrasion damage caused by rubbing of the stent against the artery wall during limb movement plays a significant role in reconstruction failure but has not been characterized. Our goals were to develop a method of assessing the abrasiveness of peripheral nitinol stents and apply it to several commercial devices. Misago, AbsolutePro, Innova, Zilver, SmartControl, SmartFlex, and Supera stents were deployed inside electrospun nanofibrillar tubes with femoropopliteal artery-mimicking mechanical properties and subjected to cyclic axial compression (25%), bending (90°), and torsion (26°/cm) equivalent to five life-years of severe limb flexions. Abrasion was assessed using an abrasion damage score (ADS, range 1-7) for each deformation mode. Misago produced the least abrasion and no stent fractures (ADS 3). Innova caused small abrasion under compression and torsion but large damage under bending (ADS 7). Supera performed well under bending and compression but caused damage under torsion (ADS 8). AbsolutePro produced significant abrasion under bending and compression but less damage under torsion (ADS 12). Zilver fractured under all three deformations and severely abraded the tube under bending and compression (ADS 15). SmartControl and SmartFlex fractured under all three deformations and produced significant abrasion due to strut penetration (ADS 20 and 21). ADS strongly correlated with clinical 12-month primary patency and target lesion revascularization rates, and the described method of assessing peripheral stent abrasiveness can guide device selection and development. STATEMENT OF SIGNIFICANCE: Poor outcomes of peripheral arterial disease stenting are related to the inability of stents to accommodate the complex biomechanics of the flexed lower limb. Abrasion damage caused by rubbing of the stent against the artery wall during limb movement plays a significant role in reconstruction failure but has not been characterized. Our study presents the first attempt at assessing peripheral stent abrasiveness, and the proposed method is applied to compare the abrasion damage caused by Misago, AbsolutePro, Innova, Zilver, SmartControl, SmartFlex, and Supera peripheral stents using artery-mimicking synthetic tubes and cyclic deformations equivalent to five life-years of severe limb flexions. The abrasion damage caused by stents strongly correlates with their clinical 12-month primary patency and target lesion revascularization rates, and the described methodology can be used as a cost-effective and controlled way of assessing stent performance, which can guide device selection and development.

Aortic mechanical and structural characteristics have profound effects on pathophysiology, but many aspects of physiologic stress-stretch state and intramural changes due to aging remain poorly understood in human tissues. While difficult to assess in vivo due to residual stresses and pre-stretch, physiologic stress-stretch characteristics can be calculated using experimentally-measured mechanical properties and constitutive modeling. Mechanical properties of 76 human descending thoracic aortas (TA) from 13 to 78-year-old donors (mean age 51±18 years) were measured using multi-ratio planar biaxial extension. Constitutive parameters were derived for aortas in 7 age groups, and the physiologic stress-stretch state was calculated. Intramural characteristics were quantified from histological images and related to aortic morphometry and mechanics. TA stiffness increased with age, and aortas became more nonlinear and anisotropic. Systolic and diastolic elastic energy available for pulsation decreased with age from 30 to 8 kPa and from 18 to 5 kPa, respectively. Cardiac cycle circumferential stretch dropped from 1.14 to 1.04, and circumferential and longitudinal physiologic stresses decreased with age from 90 to 72 kPa and from 90 to 17 kPa, respectively. Aortic wall thickness and radii increased with age, while the density of elastin in the tunica media decreased. The number of elastic lamellae and circumferential physiologic stress per lamellae unit remained constant with age at 102±10 and 0.85±0.04 kPa, respectively. Characterization of mechanical, physiological, and structural features in human aortas of different ages can help understand aortic pathology, inform the development of animal models that simulate human aging, and assist with designing devices for open and endovascular aortic repairs. Statement of significance This manuscript describes mechanical and structural changes occurring in human thoracic aortas with age, and presents material parameters for 4 commonly used constitutive models. Presented data can help better understand aortic pathology, inform the development of animal models that simulate human aging, and assist with designing devices for open and endovascular aortic repairs.

Purpose: Despite the two decades of using cell phones, there are still considerable controversies about the biological effects of the Electromagnetic Fields (EMFs) produced by cell phones. Sleep disorder among hospital staff is an important issue for the health care system not only due to the health of its employees but also to the reduction of the staff performance quality and the increase in medical errors. This study aimed to explore factors that may affect the sleep quality of hospital staff and to examine the association between sleep quality and cell phone usage. Materials and Methods: In this study, participants consisted of 288 employees (35.51 ± 8.42 years old) of two hospitals, and their sleep quality was assessed using the Pittsburgh sleep quality index. Results: Sixty-six percent of participants had good sleep quality and nearly 68% of the employees worked in shifts. The cell phone use among participants averaged 10.74 ± 3.03 years, and less than half of the staff stated that call durations of their cell phones were less than 5 h/day. More than 90% of the staff mentioned no use of hands-free. There were no statistically significant differences between job characteristics, sleep quality, and items related to cell phones, except the use of hands-free. Conclusion: In our study, using hands-free during phone calls was associated with poor quality sleep. Different factors, such as decreased levels of electromagnetic fields reaching the brain, can be involved in this effect. These results must be interpreted with caution due to the low number of subjects and the limitations of our study.

Elastic and muscular arteries differ in structure, function, and mechanical properties, and may adapt differently to aging. We compared the descending thoracic aortas (TA) and the superficial femoral arteries (SFA) of 27 tissue donors (average 41±18 years, range 13-73 years) using planar biaxial testing, constitutive modeling, and bidirectional histology. Both TAs and SFAs increased in size with age, with the outer radius increasing more than the inner radius, but the TAs thickened 6-fold and widened 3-fold faster than the SFAs. The circumferential opening angle did not change in the TA, but increased 2.4-fold in the SFA. Young TAs were relatively isotropic, but the anisotropy increased with age due to longitudinal stiffening. SFAs were 51% more compliant longitudinally irrespective of age. Older TAs and SFAs were stiffer, but the SFA stiffened 5.6-fold faster circumferentially than the TA. Physiologic stresses decreased with age in both arteries, with greater changes occurring longitudinally. TAs had larger circumferential, but smaller longitudinal stresses than the SFAs, larger cardiac cycle stretch, 36% lower circumferential stiffness, and 8-fold more elastic energy available for pulsation. TAs contained elastin sheets separated by smooth muscle cells (SMCs), collagen, and glycosaminoglycans, while the SFAs had SMCs, collagen, and longitudinal elastic fibers. With age, densities of elastin and SMCs decreased, collagen remained constant due to medial thickening, and the glycosaminoglycans increased. Elastic and muscular arteries demonstrate different morphological, mechanical, physiologic, and structural characteristics and adapt differently to aging. While the aortas remodel to preserve the Windkessel function, the SFAs maintain higher longitudinal compliance.

Planar biaxial testing is commonly used to characterize the mechanical properties of arteries, but stresses associated with specimen flattening during this test are unknown. We quantified flattening effects in human femoropopliteal arteries (FPAs) of different ages and determined how they affect the calculated arterial physiologic stress–stretch state. Human FPAs from 472 tissue donors (age 12–82 years, mean 53 ± 16 years) were tested using planar biaxial extension, and morphometric and mechanical characteristics were used to assess the flattening effects. Constitutive parameters for the invariant-based model were adjusted to account for specimen flattening and used to calculate the physiologic stresses, stretches, axial force, circumferential stiffness, and stored energy for the FPAs in seven age groups. Flattened specimens were overall 12 ± 4% stiffer longitudinally and 19 ± 11% stiffer circumferentially when biaxially tested. Differences between the stress–stretch curves adjusted and non-adjusted for the effects of flattening were relatively constant across all age groups longitudinally, but increased with age circumferentially. In all age groups, these differences were smaller than the intersubject variability. Physiologic stresses, stretches, axial force, circumferential stiffness, and stored energy were all qualitatively and quantitatively similar when calculated with and without the flattening effects. Stresses, stretches, axial force, and stored energy reduced with age, but circumferential stiffness remained relatively constant between 25 and 65 years of age suggesting a homeostatic target of 0.75 ± 0.02 MPa. Flattening effects associated with planar biaxial testing are smaller than the intersubject variability and have little influence on the calculated physiologic stress–stretch state of human FPAs.