Community Member and Faith Leader Perspectives on the Process of Building Trusting Relationships between Communities and Researchers

In the first phase of this research, we conducted, audio‐recorded, and transcribed seven focus groups with more than 50 English‐ or Spanish‐speaking women of childbearing age. Qualitative analysis revealed the following themes: (1) expectation that participation would involve relationships based on trust that is built over time and impacted by cultural factors; (2) perceived characteristics of research staff that would help facilitate the development of trusting relationships; (3) perceptions about the location of the visits that may affect trust; (4) perceptions of a research study and trust for the institution conducting the study may affect trust; (5) connecting the study to larger communities, including faith communities, could affect trust and willingness to participate. In the second phase of this research, we conducted, recorded, transcribed, and analyzed interviews with leaders from diverse faith communities to explore the potential for research partnerships between researchers and faith communities. In addition to confirming themes identified in focus groups, faith leaders described an openness to research partnerships between the university and faith communities and considerations for the formation of these partnerships. Faith leaders noted the importance of finding common ground with researchers, establishing and maintaining trusting relationships, and committing to open, bidirectional communication.     

When Is a Maze Procedure a Maze Procedure?

The initial surgical attempts to treat atrial fibrillation (AF) were isolation procedures designed to confine the arrhythmia to a specific area of the heart for relief of symptoms. The first surgical attempt to ablate AF was unsuccessful but was quickly followed by the Maze-I procedure on September 25, 1987. Because of several adverse sequelae of the Maze-I procedure, it was sequentially modified to the Maze-II and then Maze-III procedures. The Maze-IV procedure was introduced some 10 years later; these are the only 4 procedures that adhere to the concept of a maze pattern of lesions to ablate AF and leave both atria capable of being activated during normal sinus rhythm. The term maze procedure has become generic for virtually any operation designed to treat AF, but procedures that do not adhere to the concept of creating lesions of conduction block in the pattern of a maze are not maze procedures. These include, among others, the Wolf Mini-Maze, the Left-Sided Maze, and the 5-Box Maze, none of which are truly based on the maze-pattern concept. The cardinal feature of maze procedures that is necessary for both effectiveness and comparability to classical maze procedures includes lines of conduction block that preclude macro-reentry anywhere in either atrium while leaving both atria capable of activation by a sinus-generated impulse. Components essential to achieving this include appropriate lesions in both atria, the absence of gaps that allow electrical activity to bypass an intended line of block, and the absence of alternate pathways by which impulses can reach the intended maze exit.     

Nitric oxide signaling in the brain: A new target for inhaled nitric oxide?

Nitric oxide (NO) is a powerful vasodilator, involved in both physiological functions and pathophysiological alterations of various regulatory processes, for example, the maintenance of vascular tone and inflammation. The recently demonstrated impact of exogenous NO on the central nervous system extends its role under normal and pathological conditions. At times neuroprotective, at times neurotoxic, NO is capable of different effects depending upon the extent of cerebral damage, the cellular redox state, and the spatiotemporal coordinates and concentration at which it is synthesized. This review provides new insights into the short‐ and long‐term effects of endogenous and exogenous NO in brain injury. ANN NEUROL 2013;73:442–448     

Superficial Epidermolytic Ichthyosis: A Report of Two Families

Abstract: Superficial epidermolytic ichthyosis (SEI), previously known as ichthyosis bullosa of Siemens, is a rare genetic skin condition, characterized by blisters and hyperkeratosis. It can be easily confused with epidermolytic hyperkeratosis, known now as epidermolytic ichthyosis, and genetic testing can be helpful in differentiating between the two conditions. We describe two children with SEI confirmed by genetic testing, including one with a novel mutation. We also describe other affected family members with SEI.     

Accumulation of non-compressive fascicular lesions underlies NF2 polyneuropathy

A distinct polyneuropathy (PNP) syndrome affects up to 66 % of patients with neurofibromatosis II (NF2). Whether this is primarily a diffuse PNP or due to single, surgically amenable mass lesions has not yet been conclusively demonstrated. We aimed to solve this question by investigating the pathomorphological MR imaging correlate of this rare disorder. Eight patients with NF2-PNP were characterized by clinical examination, electrophysiological studies, and genetic analysis. All patients additionally underwent extended peripheral nerve imaging by a novel protocol of large-coverage high-resolution MRI. Quantitative analyses were performed by separately evaluating cross-sectional images, and by categorizing lesions into non-compressive fascicular microlesions (<2 mm), intermediate lesions (2–5 mm), and compressive macrolesions (>5 mm). The predominant imaging findings were non-compressive fascicular microlesions and intermediate lesions. Proximal-to-distal cumulative lesion burden of these lesions correlated strongly with the severity of clinical symptoms of NF2-PNP. In contrast, compressive macrolesions were not found at all in several symptomatic extremities. We conclude that proximal-to-distal accumulation of non-compressive fascicular lesions instead of compressive mass lesions predominantly underlies the clinical manifestation and severity of NF2-associated PNP. Diagnostic management may now be assisted by large-coverage high-resolution imaging of plexus and peripheral nerves. Additionally, the results underscore the feasibility of this new method, which may open up new diagnostic and investigative possibilities for other disseminated disorders of the peripheral nervous system.     

V-region mutation in vitro,in vivo,and in silico reveal the importance of the enzymatic properties of AID and the sequence environment

The somatic hypermutation of Ig variable regions requires the activity of activation-induced cytidine deaminase (AID) which has previously been shown to preferentially deaminate WRC (W = A/T, R = A/G) motif hot spots in in vivo and in vitro assays. We compared mutation profiles of in vitro assays for the 3′ flanking intron of VhJ558-Jh4 region to previously reported in vivo profiles for the same region in the Msh2^−/−Ung^−/− mice that lack base excision and mismatch repair. We found that the in vitro and in vivo mutation profiles were highly correlated for the top (nontranscribed) strand, while for the bottom (transcribed) strand the correlation is far lower. We used an in silico model of AID activity to elucidate the relative importance of motif targeting in vivo. We found that the mutation process entails substantial complexity beyond motif targeting, a large part of which is captured in vitro. To elucidate the contribution of the sequence environment to the observed differences between the top and bottom strands, we analyzed intermutational distances. The bottom strand shows an approximately exponential distribution of distances in vivo and in vitro, as expected from a null model. However, the top strand deviates strongly from this distribution in that mutations approximately 50 nucleotides apart are greatly reduced, again both in vivo and in vitro, illustrating an important strand asymmetry. While we have confirmed that AID targeting of hot and cold spots is a key part of the mutation process, our results suggest that the sequence environment plays an equally important role.     

On the origin and specificity of antibodies to neuromuscular blocking (muscle relaxant) drugs: an immunochemical perspective

Following the demonstration 25 years ago that substituted ammonium groups on neuromuscular blocking drugs (NMBDs) are the main allergenic structures recognized by IgE antibodies in the sera of some patients who experience anaphylaxis during anaesthesia, immunoassays for these drugs were quickly applied to supplement skin tests in the diagnostic assessment of suspected adverse reactions to anaesthetic agents. Many subjects who react to an NMBD do so on first exposure and this led to the speculation that the origin of allergic sensitization is an environmental agent(s) or another drug containing an ammonium ion. Direct antibody binding and hapten inhibition studies revealed that morphine, which contains a tertiary amino group, was strongly recognized by IgE in sera from anaphylactic patients and a morphine-solid phase immunoassay was found to be superior to NMBD-based assays for the detection of NMBD-reactive IgE antibodies. Extensive inhibition experiments indicate the likelihood of antibody combining site heterogeneity with recognition at the fine structural level of features additional, and adjacent to, ammonium ions. Further quantitative investigations are needed to identify these neighbouring groups on different NMBDs. Recent work has implicated the morphine analogue pholcodine as the sensitizing agent in Norway where, unlike Sweden, anaphylactic reactions to NMBDs are not uncommon and the medicament is available over-the-counter. This has led to the suggestion that allergenic sensitization to the ammonium group of pholcodine may account for the different incidences of anaphylaxis during anaesthesia in the two countries. This work is subjected to critical review and some alternative speculations on the nature and origin of the sensitizing agent(s) are presented.     

Nanoanalytical analysis of bisphosphonate-driven alterations of microcalcifications using a 3D hydrogel system and in vivo mouse model

Vascular calcification predicts atherosclerotic plaque rupture and cardiovascular events. Retrospective studies of women taking bisphosphonates (BiPs), a proposed therapy for vascular calcification, showed that BiPs paradoxically increased morbidity in patients with prior acute cardiovascular events but decreased mortality in event-free patients. Calcifying extracellular vesicles (EVs), released by cells within atherosclerotic plaques, aggregate and nucleate calcification. We hypothesized that BiPs block EV aggregation and modify existing mineral growth, potentially altering microcalcification morphology and the risk of plaque rupture. Three-dimensional (3D) collagen hydrogels incubated with calcifying EVs were used to mimic fibrous cap calcification in vitro, while an ApoE^−/− mouse was used as a model of atherosclerosis in vivo. EV aggregation and formation of stress-inducing microcalcifications was imaged via scanning electron microscopy (SEM) and atomic force microscopy (AFM). In both models, BiP (ibandronate) treatment resulted in time-dependent changes in microcalcification size and mineral morphology, dependent on whether BiP treatment was initiated before or after the expected onset of microcalcification formation. Following BiP treatment at any time, microcalcifications formed in vitro were predicted to have an associated threefold decrease in fibrous cap tensile stress compared to untreated controls, estimated using finite element analysis (FEA). These findings support our hypothesis that BiPs alter EV-driven calcification. The study also confirmed that our 3D hydrogel is a viable platform to study EV-mediated mineral nucleation and evaluate potential therapies for cardiovascular calcification.

Atherosclerotic plaque rupture is the leading cause of myocardial infarction and stroke (1, 2). Studies assessing the correlation between calcium scores and cardiovascular events have demonstrated a predictive power that is superior to and independent from that of lipid scores (3, 4). Additionally, clinical imaging studies have revealed that the risk of plaque rupture is further heightened by the presence of small, “spotty” calcifications, or microcalcifications (5, 6), and cardiovascular risk is inversely correlated with the size of calcific deposits, quantified as a calcium density score (7). Indeed, computational modeling has demonstrated that, while large calcifications can reinforce the fibrous cap (8), microcalcifications (typically 5 to 15 μm in diameter) uniquely mediate an increase in mechanical stress of the relatively soft, collagen-rich fibrous cap (9–12).Histologic studies have revealed the presence of cell-derived vesicles within calcifying atherosclerotic lesions (13–16). The inflammatory environment of the atherosclerotic lesion can induce vascular smooth muscle cells (vSMCs) to take on an osteochondrogenic phenotype and release calcifying extracellular vesicles (EVs) (17–19). Macrophages have also been shown to release procalcifying vesicles (20, 21). Thus, just as bone formation is hypothesized to be an active, cell-driven process (22, 23), mediated by calcifying matrix vesicles, atheroma-associated calcification may similarly be initiated by the production and aggregation of calcifying EVs (11, 20, 24–28).One proposed strategy for halting pathologic calcification has been the use of bisphosphonates (BiPs). BiPs are analogs of pyrophosphate (29), a naturally occurring compound derived in vivo from adenosine triphosphate (ATP) (30). Pyrophosphate binds to calcium phosphate and inhibits calcification via physicochemical mechanisms, namely, by blocking calcium and phosphate ions from forming crystals, preventing crystal aggregation, and preventing mineral transformation from amorphous calcium phosphate to hydroxyapatite (29). BiPs were identified as pyrophosphate analogs that, unlike pyrophosphate itself, resist enzymatic hydrolysis. A second, distinct property of BiPs is the ability to inhibit bone resorption via biological activity directed against osteoclasts following osteoclast endocytosis of the BiP molecule adsorbed to the surface of bone (29, 31). First-generation, or nonnitrogen-containing BiPs, are incorporated into nonhydrolyzable ATP analogs, and induce osteoclast apoptosis by limiting ATP-dependent enzymes. In contrast, nitrogen-containing BiPs inhibit farnesyl pyrophosphate synthetase and thereby induce osteoclast apoptosis (31).In vivo animal investigations have been performed to explore the potential for BiPs to inhibit cardiovascular calcification. Studies of first-generation BiPs revealed that the doses required to inhibit cardiovascular calcification also critically compromised normal bone mineralization (29, 32). However, newer, nitrogen-containing BiPs effectively arrested cardiovascular calcification in animal models at doses that did not compromise bone formation (32). Further, while it has been proposed that BiP treatment modifies cardiovascular calcification via its impact on bone-regulated circulating calcium and phosphate levels, a study in uremic rats demonstrated that BiP treatment inhibited medial aortic calcification with no significant change in plasma calcium and phosphate levels (33). The same study demonstrated that BiP treatment inhibited calcification of explanted rat aortas, indicating that BiPs can act directly on vascular tissue, independent of bone metabolism (33).Retrospective clinical data examining the effect of BiP therapy on cardiovascular calcification has demonstrated conflicting findings and intriguing paradoxes. In women with chronic kidney disease, BiP therapy decreased the mortality rate for patients without a prior history of cardiovascular disease (34), but for those patients with a history of prior cardiovascular events, BiP therapy was associated with an increased mortality rate (35). In another study, BiP therapy correlated with a lower rate of cardiovascular calcification in older patients (>65 y), but a greater rate in younger patients (<65 y) (36). These clinical findings motivated our study, in which we sought to further understand how BiP therapy impacts cardiovascular outcomes. Given that cardiovascular calcification, and especially the presence of microcalcification, is a strong and independent risk factor for adverse cardiac events, and BiPs are prescribed to modulate pathologies of mineralization, we hypothesize that BiPs modulate cardiovascular outcomes by altering the dynamics of cardiovascular calcification.EVs are smaller than the resolution limits of traditional microscopy techniques, hindering studies into the mechanisms of calcification nucleation and growth. We previously developed an in vitro collagen hydrogel platform that allowed the visualization of calcific mineral development mediated by EVs isolated from vSMCs (24). Using superresolution microscopy, confocal, and electron microscopy techniques, we showed that calcification requires the accumulation of EVs that aggregate and merge to build mineral. Collagen serves as a scaffold that promotes associations between EVs that spread into interfibrillar spaces. The resultant mineral that forms within the collagen hydrogel appears spectroscopically similar to microcalcifications in human tissues and allows the study of these structures on the time scale of 1 wk. In this study, we utilized this three-dimensional (3D) acellular platform to examine the direct effect of ibandronate, a nitrogen-containing BiP, on the EV-directed nucleation and growth of microcalcifications, a process that cannot be isolated from cellular and tissue-level mechanisms in a more complex, in vivo system. In parallel, we utilized a mouse model of atherosclerosis to assess the effect of ibandronate therapy on plaque-associated calcification, comparing mineral morphologies between the in vitro and in vivo samples. We hypothesize that BiPs block EV aggregation and modify existing mineral growth, potentially altering microcalcification morphology and the risk of plaque rupture. Understanding the EV-specific action of BiPs is imperative both to develop anticalcific therapeutics targeting EV mineralization and to understand one potential mechanism driving the cardiovascular impact of BiPs used in clinical settings.     

Radiographic changes after colonoscopic decompression for acute pseudo-obstruction

PURPOSE: Colonoscopy has been the principal tool for decompression in acute colonic pseudo-obstruction, known as Ogilvie's syndrome. The objectives of this study were to determine the immediate effect of colonoscopy on the cecal diameter (measured on supine radiographs) and to delineate possible correlations in the diameters of dilated segments of the colon. METHODS: The charts and radiographs of 24 patients who had colonoscopic decompression for acute colonic pseudo-obstruction between 1992 and 1997 at the San Diego Veterans Affairs Medical Center and the University of California, San Diego Hospitals were reviewed. We measured cecal, transverse, descending, and sigmoid colon diameters on serial radiographs up to the point of clinical resolution. RESULTS: Mean ± standard deviation cecal diameter change (between initial and post-decompression films) was –2±3.4 cm at four hours and –2.2±3.3 cm one day after decompression. On the daily radiographs between colonoscopic decompression and clinical resolution, there was a close correlation between the diameter of the cecum and that of the transverse colon (P<0.05). There was no correlation between the cecal diameter and that of the descending or sigmoid colon. CONCLUSIONS: Colonoscopic decompression only causes a small decrease in cecal size in the patient with acute colonic pseudo-obstruction. Dilation patterns of the cecum and transverse colon are significantly correlated in acute colonic pseudo-obstruction. This correlation provides additional support to the contention that the same pathophysiology affects these two segments of the colon.Presented at the joint meeting of the Northwest Society of Colon and Rectal Surgeons, Northern California Society of Colon and Rectal Surgeons, and Southern California Society of Colon and Rectal Surgeons, Incline Village, Nevada, August 18 to 21, 1999.