In situ longitudinal pre-stretch in the human femoropopliteal artery

In situ longitudinal (axial) pre-stretch (LPS) plays a fundamental role in the mechanics of the femoropopliteal artery (FPA). It conserves energy during pulsation and prevents buckling of the artery during limb movement. We investigated how LPS is affected by demographics and risk factors, and how these patient characteristics associate with the structural and physiologic features of the FPA. LPS was measured in n = 148 fresh human FPAs (14–80 years old). Mechanical properties were characterized with biaxial extension and histopathological characteristics were quantified with Verhoeff–Van Gieson Staining. Constitutive modeling was used to calculate physiological stresses and stretches which were then analyzed in the context of demographics, risk factors and structural characteristics. Age had the strongest negative effect (r = −0.812, p \u3c 0.01) on LPS and could alone explain 66% of LPS variability. Male gender, higher body mass index, hypertension, diabetes, coronary artery disease, dyslipidemia and tobacco use had negative effects on LPS, but only the effect of tobacco was not associated with aging. FPAs with less pre-stretch had thicker medial layers, but thinner intramural elastic fibers with less dense and more fragmented external elastic laminae. Elastin degradation was associated with decreased physiological tethering force and longitudinal stress, while circumferential stress remained constant. FPA wall pathology was negatively associated with LPS (r = −0.553, p \u3c 0.01), but the effect was due primarily to aging. LPS in the FPA may serve as an energy reserve for adaptive remodeling. Reduction of LPS due to degradation and fragmentation of intramural longitudinal elastin during aging can be accelerated in tobacco users

In situ longitudinal pre-stretch in the human femoropopliteal artery

In situ longitudinal (axial) pre-stretch (LPS) plays a fundamental role in the mechanics of the femoropopliteal artery (FPA). It conserves energy during pulsation and prevents buckling of the artery during limb movement. We investigated how LPS is affected by demographics and risk factors, and how these patient characteristics associate with the structural and physiologic features of the FPA. LPS was measured in n = 148 fresh human FPAs (14–80 years old). Mechanical properties were characterized with biaxial extension and histopathological characteristics were quantified with Verhoeff–Van Gieson Staining. Constitutive modeling was used to calculate physiological stresses and stretches which were then analyzed in the context of demographics, risk factors and structural characteristics. Age had the strongest negative effect (r = −0.812, p \u3c 0.01) on LPS and could alone explain 66% of LPS variability. Male gender, higher body mass index, hypertension, diabetes, coronary artery disease, dyslipidemia and tobacco use had negative effects on LPS, but only the effect of tobacco was not associated with aging. FPAs with less pre-stretch had thicker medial layers, but thinner intramural elastic fibers with less dense and more fragmented external elastic laminae. Elastin degradation was associated with decreased physiological tethering force and longitudinal stress, while circumferential stress remained constant. FPA wall pathology was negatively associated with LPS (r = −0.553, p \u3c 0.01), but the effect was due primarily to aging. LPS in the FPA may serve as an energy reserve for adaptive remodeling. Reduction of LPS due to degradation and fragmentation of intramural longitudinal elastin during aging can be accelerated in tobacco users

\u3ci\u3eIN SITU\u3c/i\u3e LONGITUDINAL PRE-STRETCH IN THE HUMAN FEMOROPOPLITEAL ARTERY

In situ longitudinal (axial) pre-stretch (LPS) plays a fundamental role in the mechanics of the femoropopliteal artery (FPA). It conserves energy during pulsation and prevents buckling of the artery during limb movement. We investigated how LPS is affected by demographics and risk factors, and how these patient characteristics associate with the structural and physiologic features of the FPA. LPS was measured in n=148 fresh human FPAs (14–80 years old). Mechanical properties were characterized with biaxial extension and histopathological characteristics were quantified with Verhoeff-Van Gieson Staining. Constitutive modeling was used to calculate physiological stresses and stretches which were then analyzed in the context of demographics, risk factors and structural characteristics. Age had the strongest negative effect (r=−0.812, p\u3c0.01) on LPS and could alone explain 66% of LPS variability. Male gender, higher body mass index, hypertension, diabetes, coronary artery disease, dyslipidemia and tobacco use had negative effects on LPS, but only the effect of tobacco was not associated with aging. FPAs with less pre-stretch had thicker medial layers, but thinner intramural elastic fibers with less dense and more fragmented external elastic laminae. Elastin degradation was associated with decreased physiological tethering force and longitudinal stress, while circumferential stress remained constant. FPA wall pathology was negatively associated with LPS (r = −0.553, p\u3c0.01), but the effect was due primarily to aging. LPS in the FPA may serve as an energy reserve for adaptive remodeling. Reduction of LPS due to degradation and fragmentation of intramural longitudinal elastin during aging can be accelerated in tobacco users

A temporal examination of calcium signaling in cancer- from tumorigenesis, to immune evasion, and metastasis

Abstract Background Although the study of calcium (Ca2+) is classically associated with excitable cells such as myocytes or neurons, the ubiquity of this essential element in all cellular processes has led to interest in other cell types. The importance of Ca2+ to apoptosis, cell signaling, and immune activation is of special import in cancer. Main Here we review the current understanding of Ca2+ in each of these processes vital to the initiation, spread, and drug resistance of malignancies. We describe the involvement of Ca2+, and Ca2+ related proteins in cell cycle checkpoints and Ca2+ dependent apoptosis and discuss their roles in cellular immortalization. The role of Ca2+ in inter-cellular communication is also discussed in relevance to tumor-stromal communication, angiogenesis, and tumor microinvasion. The role that Ca2+ plays in immune surveillance and evasion is also addressed. Finally, we discuss the possibility of targeting Ca2+ singling to address the most pressing topics of cancer treatment: metastatic disease and drug resistance. Conclusion This review discusses the current understanding of Ca2+ in cancer. By addressing Ca2+ facilitated angiogenesis, immune evasion, metastasis, and drug resistance, we anticipate future avenues for development of Ca2+ as a nexus of therapy

Evolution of Intracranial-Intracranial Bypass Surgery: A Bibliometric Analysis

OBJECTIVE: Modern cerebrovascular bypass surgery uses either extracranial-intracranial (EC-IC) or intracranial-intracranial (IC-IC) approaches. Compared with EC-IC bypasses, IC-IC bypasses allow neurosurgeons to safely address tumors, aneurysms, and other lesions using shorter grafts that are well matched to the size of recipient vessels. Fewer than 100 articles have been published on IC-IC bypasses compared with more than 1000 on EC-IC bypasses. This study examined the increase of interest and innovation in IC-IC bypass. METHODS: PubMed and Web of Science were searched using keywords specific to IC-IC bypass, yielding 717 articles supplemented with 36 reports from other databases and gray literature. The articles were reviewed, and 98 articles were selected for further evaluation. Final articles were categorized as innovations or retrospective studies. Publication metrics were passed through an analytic program to assess statistical measures of growth. RESULTS: The number of publications describing innovations (n = 52) and retrospective studies (n = 46) in IC-IC surgical techniques increased exponentially (R = 0.983 and R = 0.993, respectively), with both interest and research in the field increasing. The rate of publications in each group also increased. In recent years, increasing numbers of global institutions have researched and published on IC-IC bypasses. CONCLUSIONS: As more work is undertaken on IC-IC bypasses, it is critical for knowledge to be shared through research, collaboration, publication, and early teaching within residency training programs. This field has increased exponentially in the past 2 decades and has yet to reach an inflection point, indicating possible additional interest and growth over time

Abstract Number ‐ 281: Clinical and Epidemiological Characteristics of Moyamoya Disease Presenting with Concomitant Autoimmune Conditions

Introduction Moyamoya disease was first described in the 1950’s. After over six decades, however, the underlying etiology of Moyamoya still remains unknown. It has been postulated that underlying inflammatory or autoimmune (AI) processes may play a role in the development of this condition. In order to further investigate this hypothesis, we studied the clinical and epidemiological attributes of patients with concurrent Moyamoya disease and AI condition(s). Methods A systematic review was performed including studies reporting patient level data of Moyamoya disease and concomitant autoimmune disease. Relevant studies were identified using Preferred reporting Items for Systematic Reviews and Meta‐Analysis criteria. Results There were 739 results of which 149 were included in this study. The first reports of concurrent Moyamoya and AI occurred in 1991 and involved 2 cases of Moyamoya and associated Graves’ disease. These patients were treated with antithyroid medication alone and showed improvement. Altogether, our search yielded a total of 257 patients (192 females, 48 males, 17 unspecified). A total of 158 cases were reported as “Moyamoya Disease” and 99 were reported as “Moyamoya Syndrome/Vasculopathy.” Most cases were ischemic (175 ischemic, 15 hemorrhagic) in nature. Bilaterality of the disease was reported in 130 cases, unilaterality in 34 cases. The most commonly reported ethnicity was Chinese (26 cases), followed by Japanese (17 cases), and Korean (17 cases). The most common co‐presenting AI conditions were Graves’ disease (150 cases, 58.4%), Lupus (26 cases, 10.1%), antiphospholipid syndrome (19 cases, 7.4%), Type 1 Diabetes (19 cases, 7.4%), and Multiple Sclerosis (7 cases, 2.7%). Conclusions There are numerous reports describing patients diagnosed with Moyamoya in addition to coexisting AI conditions. Our study shows that the demographic characteristics of co‐presentation align with the common autoimmune (female predominance) and Moyamoya (high east Asian prevalence) attributes. These results warrant further investigation into a possible causal or synergistic relationship between Moyamoya and AI disease

Abstract Number ‐ 282: Surgical Treatment for Moyamoya Disease with Coexisting Autoimmune Conditions: A Systematic Review

Introduction There have been several studies of Moyamoya disease (MMD) with concurrent autoimmune (AI) disease. It has been proposed that there may be a causal or synergistic effect of autoimmune and inflammatory conditions in patients with MMD. As such, in the present study we seek to characterizethe surgical outcomes of adults and children with MMD and coexisting AI conditions. Methods A systematic review was performed of published studies reporting patient level data of Moyamoya disease and concomitant autoimmune disease. Relevant studies were identified using Preferred reporting Items for Systematic Reviews and Meta‐Analysis criteria. Results A total of 149 studies were included, encompassing 257 patients. Of the 257 patients with concurrent AI and MMD, 107 (88 females, 19 males) underwent surgery. The average age was 31.3 years (Range 5–65; SD 12.5). Five cases presented with hemorrhagic symptoms, 87 ischemic, and 15 were unspecified. The most commonly associated AI conditions were Graves’ disease (71 cases, 66.4%), Lupus (17 cases, 15.9%), and T1DM (6 cases, 5.6%).Follow‐up was reported in 25 cases and was an average of 17.8 months. Surgical outcomes were reported in 82 cases; 63 (76.8%) improved, 7 (8.5%) were stable, 9 (10.9%) developed a new deficit, and 3 (3.7%) died at most recent follow up. Eight patients (7.5%) had disease progression. 63 (58.8%) patients were treated with additional autoimmune therapy although this therapy did not lead to any difference in outcomes. Twenty patients (18.7%) required additional supportive medical therapy (eg: aspirin, statins). Conclusions Moyamoya disease may be multifactorial. Patients with concomitant AI and Moyamoya disease may be at increased risk and warrant additional surveillance or intervention. The ideal therapy for these patients remains to be understood. These findings warrant further study into optimal diagnostic and therapeutic techniques for concomitant MMD and AI conditions