Positional behaviors have been broadly quantified across the Order Primates, and in several other mammalian lineages, to contextualize adaptations to, and evolution within, an arboreal environment. Outside of Mammalia, however, such data are yet to be reported. In this study, we present the first quantitative report of positional behavior within Aves, presenting 11,246 observations of scan sampling data from a colony of Monk Parakeets (Myiopsitta monachus) from Brooklyn, New York City. Each scan recorded locomotor and postural behavior and information about weather condition, temperature, and substrate properties (e.g., type, size, orientation). A distinction was also recorded between natural and artificial substrates. Parrots exhibited a strong preference for small and terminal branches, a selection which may reflect targeted foraging of new fruit growth and leaf-buds. We further observed that the gait transition from walking to sidling appears primarily driven by substrate size, with the former preferred on the ground and on large, broad substrates and the latter used to navigate smaller branches. Finally, we observed an increase in locomotor diversity on artificial versus naturally occurring substrates. This demonstrates the importance of a flexible behavioral repertoire in facilitating a successful transition towards an urban landscape in introduced species.

The tortuous carotid artery is a rare anatomic abnormality defined as vascular elongation leading to an altered course. It can be discovered incidentally or have clinically significant manifestations. The most common location is the internal carotid artery or, less commonly, the common carotid artery. Bilateral tortuous carotid arteries can also occur, leading to "kissing carotids" where the carotid arteries are juxtaposed. We describe two cases of carotid artery tortuosity in patients with risk factors associated with its development. One case is of a 91-year-old female presenting with a cerebrovascular accident and an incidental finding of tortuosity of the right common carotid artery mimicking the appearance of "kissing carotids." The other case concerns a 66-year-old female with a symptomatic tortuous left internal carotid artery. This report aims to inform clinicians of the differences in the anatomical features, pathogenesis, and possible clinical implications of these variants.

We describe the case of a 19-year-old woman with no significant medical history who developed progressive right-sided neck pain and palpitations one month following a pregnancy complicated by preeclampsia. Family history was significant for unprovoked deep vein thrombosis (DVT) and pulmonary embolism (PE) in her father at age 44. Systemic examination revealed mild swelling of the right upper extremity with pain on palpation. Computed tomography (CT) of the thorax with contrast demonstrated extensive occlusion of right upper extremity veins and collateralization of chest wall veins. Pulmonary emboli were present bilaterally in the segmental and subsegmental branches of the lower lobe pulmonary arteries. CT of the abdomen with contrast revealed thrombi in the left common and external iliac veins. Thrombophilia screening was normal. The patient was treated with enoxaparin and ampicillin/sulbactam. Her clinical condition improved, and she was discharged with an outpatient clinic follow-up appointment.

Introduction: The level of homoarginine (hArg) in plasma correlates inversely with cardiovascular and renal disease. However, the cardioprotective mechanism of hArg in renal disease is currently unknown. In this study, we assessed hArg’s effects on cardiovascular function in mice with chronic kidney disease (CKD). Hypothesis: We have previously reported that hArg reduces fibrosis and helps preserve ejection fraction in a model of coronary artery disease. We now hypothesize that hArg supplementation will 1) decrease cardiac and renal fibrosis and inflammation in a model of CKD, 2) preserve cardiac geometry and function, 3) increase renal artery blood flow, and 4) increase survival. Methods: The mice used in this study had a mutation in the low density lipoprotein receptor on the C57BL/6 genetic background. Mice of both sexes (n=28) were fed a standard rodent diet supplemented with 0.1% (F) and 0.2% (M) adenine to induce CKD. Mice were randomly assigned to 14 μg/ml hArg (in drinking water) or placebo (PBO). Cardiac structure and function as well as renal blood flow were measured via high frequency ultrasound (Vevo 3100, VisualSonics). Results: LV geometry data of hArg treated male mice showed increased left ventricular (LV) mass (p<0.05) with normal LV internal diameter and increased LV wall thickness (p<0.01). In terms of cardiac function, ejection fraction (EF, p<0.05), fractional shortening (p<0.01), and cardiac output (p<0.01) were also increased in hArg treated male mice compared to placebo. No differences in renal blood flow were observed. Survival was not affected by hArg. Additionally, we observed decreased food consumption (p<0.01) and fecal output (p<0.001) in hArg treated mice with no difference in urine output compared with placebo. Conclusion: hArg treated male mice developed physiologic cardiac hypertrophy with preserved EF in the absence of LV dilation. Additionally, hArg affected the metabolic state of treated mice reflected in food consumption.