In Vivo Flow Measurements of Murine Renal Arteries and Veins with High Frequency Ultrasound

The number of glomeruli in the kidneys has been shown to have an effect on the decline in renal function over time (Brenner, Garcia, Anderson 1988). Furthermore, flow in the renal arteries and veins may depend on the number of glomeruli in the kidney. Consistent in vivo measurements of volumetric flow in the renal arteries and veins are difficult to obtain. Thus, the purpose of this study was to develop non-invasive imaging techniques capable of estimating arterial and venous flow to kidneys. A high-frequency small animal ultrasound system was chosen based upon its excellent spatial and temporal resolution when imaging mice (Vevo 2100, VisualSonics, Inc.). Velocity profiles of the renal arteries and veins in C57BL/6 male mice (n=4) were measured. Motion, color Doppler, and pulsed wave Doppler data were acquired and used to determine renal diameter, maximum velocity, mean velocity, and volumetric flow for both kidneys. For the renal artery the average volumetric flow was 33.31±7.16 mm3/s and for the renal vein it was 30.23±4.58 mm3/s. The next step will be imaging the same animals multiple times to ensure that these measurements are consistent over prolonged periods of time. Then data will be collected from different breeds of mice to conclude whether or not differences in glomeruli number affect renal flow. Measurement of volumetric flow in the renal arteries and veins can lead to important insights into how the glomeruli density in kidneys relates to renal flow and function

Visualization of Complex Flow Patterns in Angiotensin II-Induced Dissecting Murine Abdominal Aortic Aneurysms with High Frequency Ultrasound

Abdominal aortic aneurysm (AAA) rupture is a common cause of mortality in the United States. Current treatments are only employed once the risk of rupture outweighs the risks associated with surgery. Murine models have been developed to characterize AAA pathogenesis in the hope that new treatments will be developed. For this study, angiotensin II (AngII) was infused subcutaneously into apolipoprotein E-deficient (ApoE-/-) mice using an osmotic mini-pump over 28 days. ApoE-/- mice (16-week-old, 3 females, 2 males) were imaged using a VisualSonics Vevo 2100 high frequency ultrasound before pump implantation and 3, 7, 14, 21, and 27 days following implantation. Images were acquired in the transverse and longitudinal planes from the suprarenal region of the aorta. Blood pressure measurements were taken using a tail-cuff system (CODA, Kent Scientific). Three mice (1 female, 2 male) developed aneurysms within the first 14 days of infusion. Pre-study abdominal aortas had a diastolic diameter of 0.84±0.09 mm and a systolic diameter of 0.96±0.08 mm. By day 21, AAAs had a diastolic diameter of 1.51±0.59 mm and a systolic diameter of 1.56±0.59 mm. Initially, mice had a systolic blood pressure of 111.94±6.53 mmHg and a diastolic pressure of 82.38±5.13 mmHg. These pressures steadily elevated but eventually began to plateau. By day 27, systolic pressure had risen to 154.92±11.43 mmHg and diastolic pressure to 115.77±10.25 mmHg. Color Doppler images revealed complex, recirculating flow within the aneurysms, a phenomenon which could affect vessel remodeling. In conclusion, this study utilized in vivo sonographic methods to characterize AAA development

Psychopharmacologic Treatment of Children Prenatally Exposed to Drugs of Abuse

Objective This pilot study compared the pharmacologic treatment history and clinical outcomes observed in pediatric outpatients with psychiatric disorders exposed to drugs of abuse in utero to those of an age-matched, sex-matched and psychiatric disorder-matched, non-drug-exposed group. Methods In this matched cohort study, medical records of children treated at an academic, child and adolescent psychiatry outpatient clinic were reviewed. Children with caregiver-reported history of prenatal drug exposure were compared with a non-drug-exposed control group being cared for by the same providers. Patients were rated with the Clinical Global Impressions—Severity scale (CGI-S) throughout treatment. The changes in pre-treatment and post-treatment CGI-S scores and the total number of medication trials were determined between groups. Results The drug-exposed group (n = 30) had a higher total number of lifetime medication trials compared with the non-drug-exposed group (n = 28) and were taking significantly more total medications, at their final assessment. Unlike the non-drug-exposed group, the drug-exposed group demonstrated a lack of clinical improvement. Conclusions These results suggest that in utero drug-exposed children may be more treatment-refractory to or experience greater side effects from the pharmacologic treatment of psychiatric disorders than controls, although we cannot determine if early environment or drugs exposure drives these findings

Students\u27 Perceptions of STEM Learning After Participating in a Summer Informal Learning Experience

Background: Informal learning environments increase students’ interest in STEM (e.g., Mohr‐Schroeder et al. School Sci Math 114: 291–301, 2014) and increase the chances a student will pursue a STEM career (Kitchen et al. Sci Educ 102: 529–547, 2018). The purpose of this study was to examine the impact of an informal STEM summer learning experience on student participants, to gain in-depth perspectives about how they felt this experience prepared them for their in-school mathematics and science classes as well as how it influenced their perception of STEM learning. Students’ attitudes and perceptions toward STEM are affected by their motivation, experience, and self-efficacy (Brown et al. J STEM Educ Innov Res 17: 27, 2016). The academic and social experiences students’ have are also important. Traditionally, formal learning is taught in a solitary form (Martin Science Education 88: S71–S82, 2004), while, informal learning is brimming with chances to connect and intermingle with peers (Denson et al. J STEM Educ: Innovations and Research 16: 11, 2015). Results: Informal learning environments increase students’ interest in STEM (e.g., Mohr‐Schroeder et al. School Sci Math 114: 291–301, 2014) and increase the chances a student will pursue a STEM career (Kitchen et al. Sci Educ 102: 529–547, 2018). The purpose of this study was to examine the impact of an informal STEM summer learning experience on student participants, to gain in-depth perspectives about how they felt this experience prepared them for their in-school mathematics and science classes as well as how it influenced their perception of STEM learning. Students’ attitudes and perceptions toward STEM are affected by their motivation, experience, and self-efficacy (Brown et al. J STEM Educ Innov Res 17: 27, 2016). The academic and social experiences students’ have are also important. Traditionally, formal learning is taught in a solitary form (Martin Science Education 88: S71–S82, 2004), while, informal learning is brimming with chances to connect and intermingle with peers (Denson et al. J STEM Educ: Innovations and Research 16: 11, 2015). Conclusions: By using authentic STEM workplaces, the STEM summer learning experience fostered a learning environment that extended and deepened STEM content learning while providing opportunity and access to content, settings, and materials that most middle level students otherwise would not have access to. Students also acknowledged the access they received to hands-on activities in authentic STEM settings and the opportunities they received to interact with STEM professionals were important components of the summer informal learning experience

Differences in reef fish assemblages between populated and remote reefs spanning multiple archipelagos across the central and western Pacific

Comparable information on the status of natural resources across large geographic and human impact scales provides invaluable context to ecosystem-based management and insights into processes driving differences among areas. Data on fish assemblages at 39 US flag coral reef-areas distributed across the Pacific are presented. Total reef fish biomass varied by more than an order of magnitude: lowest at densely-populated islands and highest on reefs distant from human populations. Remote reefs (<50 people within 100 km) averaged ~4 times the biomass of “all fishes” and 15 times the biomass of piscivores compared to reefs near populated areas. Greatest within-archipelagic differences were found in Hawaiian and Mariana Archipelagos, where differences were consistent with, but likely not exclusively driven by, higher fishing pressure around populated areas. Results highlight the importance of the extremely remote reefs now contained within the system of Pacific Marine National Monuments as ecological reference areas

Human Grasp Assist Device Soft Goods

A grasp assist system includes a glove and a flexible sleeve. The glove includes a digit such as a finger or thumb, a force sensor configured to measure a grasping force applied to an object by an operator wearing the glove, and adjustable phalange rings positioned with respect to the digit. A saddle is positioned with respect to the finger. A flexible tendon is looped at one end around the saddle. A conduit contains the tendon. A conduit anchor secured within a palm of the glove receives the conduit. The sleeve has pockets containing an actuator assembly connected to another end of the tendon and a controller. The controller is in communication with the force sensor, and calculates a tensile force in response to the measured grasping force. The controller commands the tensile force from the actuator assembly to tension the tendon and thereby move the finger

Three Dimensional Quantification of Angiotensin II-Induced Murine Abdominal Aortic Aneurysms Using High Frequency Ultrasound

Abdominal aortic aneurysms (AAAs), a localized dilation of the vessel wall of 50% or more above normal, claims approximately 14,000 U.S. lives yearly due to aortic rupture. This commonly asymptomatic disease can only be treated by endovascular stent grafts or invasive surgery, usually after the AAA diameter reaches 5 cm. Because these treatment methods carry serious risk, stem cell therapy is being explored in order to provide a low risk option for managing smaller AAAs. To determine if stem cell therapy, once administered, could stabilize or reduce AAA growth, baseline 3D ultrasound measurements in a control group were first needed. High frequency ultrasound was used on apolipoprotein E-deficient (apoE-/-) mice given angiotensin II (AngII) from subcutaneously implanted osmotic mini pumps. This mouse model developed dissecting AAAs, containing a false and true lumen, which were clearly visualized and quantified using 3D ultrasound imaging. With this ultrasound technique, we found that aneurysm diameter, total volume, and false lumen volume all increased steadily over a period of 28 days once AAAs formed. These data suggest our noninvasive, 3D ultrasound technique can be used to monitor the progression of aneurysms that may be delayed once stem cell therapy is administered

Nonlinear Optical Microscopy of Murine Abdominal Aortic Aneurysm

Abdominal aortic aneurysm (AAA) is a cardiovascular disease characterized by dilation and weakening of the vessel wall. AAA rupture is responsible for approximately 14,000 deaths annually in the United States [1]. Nonlinear optical (NLO) microscopy presents new possibilities for analyzing AAA tissue samples from murine models. Common NLO techniques are two-photon excitation fluorescence (TPEF), which detects the intrinsic autofluorescent properties of elastin, and second-harmonic generation (SHG), which is specific for collagen fibrils. Elastin and collagen, two major extracellular matrix components, help the aortic wall withstand internal pressure. Murine AAAs were created through 1) subcutaneous continuous systemic infusion of angiotensin II (AngII) in hyperlipidemic apolipoprotein E-deficient mice and 2) by intraluminal infusion of elastase (low 0.5 U/ml and high 25 U/ml concentrations) into the infrarenal aorta of rats [2]. We imaged aneurysmal and control tissue using TPEF and SHG and compared the resulting images to sections stained with standard elastin and collagen markers. TPEF images revealed disorganized elastin sheets and SHG images indicated collagen turnover after aneurysm formation. We quantified the relative degree of elastin degradation and collagen content in the aortic media within a user-defined area on sections stained with Verhoeff-van Gieson (VVG) or Masson’s trichrome (MTC), as well as on TPEF and SHG images. Our analysis with VVG-stained sections shows that elastin content in AAA tissue is significantly decreased by 64% in AngII models (P=0.02), by 34% in low concentration elastase models (P=0.07), and by 99% in high concentration elastase models (P=0.03), relative to control aortic tissue

A Long-Term Vision for an Ecologically Sound Platte River

The Platte River extends about 310 mi (499 km) from North Platte, Nebraska, to its terminus at the Missouri River confluence near Plattsmouth, Nebraska. The Platte River Valley is a continentally significant ecosystem that serves as a major stopover for migratory waterbirds in the Central Flyway including the endangered Whooping Crane (Grus americana) and \u3e1 million Sandhill Cranes (Antigone canadensis) at the peak of spring migration. However, the Platte River Valley also supports a great diversity of avifauna including grassland breeding birds, native stream fish, vascular plants, herpetofauna, mammals, pollinators, and aquatic macroinvertebrates. Despite ongoing conservation efforts since the mid-1970s the ecosystem remains largely conservation dependent and an increasing number of species across taxa are being considered at risk of regional extirpation or outright extinction. However, given the attention provided to conservation in the Platte River Valley and the need to maintain ecologically functional stopover sites in the Central Flyway, there is a great opportunity to create a resilient refugium for biodiversity conservation in the central Great Plains. To that end we convened a working group of \u3e18 individuals representing \u3e9 organizations including representatives from non-profit conservation organizations, universities, and state and federal natural resource agencies to develop a long-term vision for an ecologically sound Platte River Valley (PRV). We met in groups of varying size for \u3e170 hours throughout a more than 3-year period and developed conservation priorities and objectives using a landscape design process. Landscape design is an interdisciplinary conservation planning process that incorporates components of landscape ecology and social dimensions of natural resources with the explicit intention of improving conservation implementation.https://digitalcommons.unl.edu/zeabook/1128/thumbnail.jp