The Evaluation of Virtual Reality Neuroanatomical Training Utilizing Photorealistic 3D Models in Limited Body Donation Program Settings

Background Neuroanatomy is one of the most complex areas of anatomy to teach to medical students. Traditional study methods such as atlases and textbooks are mandatory but require significant effort to conceptualize the three-dimensional (3D) aspects of the neuroanatomical regions of interest. Objectives To test the feasibility of human anatomy teaching medical students in a virtual reality (VR) immersive environment using photorealistic three-dimensional models (PR3DM) of human anatomy, in a limited anatomical body donation program. Methods We used surface scanning technology (photogrammetry) to create PR3DM of brain dissections. The 3D models were uploaded to VR headsets and used in immersive environment classes to teach second-year medical students. Twenty-eight medical students (mean age 20.11, SD 1.42), among which 19 females (n=28/67.9%) and nine males (n=28/32.1%), participated in the study. The students had either none or minimal experience with the use of VR devices. The duration of the study was three months. After completing the curriculum, a survey was done to examine the results. Results The average rating of the students for their overall experience with the method is 4.57/5 (SD=0.63). The "Possibility to study models from many points of view" and "Good Visualization of the models" were the most agreed upon advantages, with 24 students (n=28, 85.7%), and 95% confidence intervals (CI) [0.6643, 0.9532]. The limited availability of the VR headsets was the major disadvantage as perceived by the students, with 11 students (n=28, 39.3%), 95% CI [0.2213, 0.5927] having voted for the option. The majority of the students (25) (n=28, 89.2%, SD=0.31) agreed with the statement that the use of VR facilitated their neuroanatomy education. Conclusion This study shows the future potential of this model of training in limited cadaver dissection options to provide students with modern technological methods of training. Our first results indicate a prominent level of student satisfaction from VR training with minimum negative reactions to the nature of headsets. The proof of concept for the application of photorealistic models in VR neuroanatomy training combined with the initial results of appreciation among the students predisposes the application of the method on a larger scale, adding a nuance to the traditional anatomy training methods. The low number of headsets used in the study limits the generalization of the results but offers possibilities for future perspectives of research.

The Genotype and Phenotypes in Families (GPF) platform manages the large and complex data at SFARI

The exploration of genotypic variants impacting phenotypes is a cornerstone in genetics research. The emergence of vast collections containing deeply genotyped and phenotyped families has made it possible to pursue the search for variants associated with complex diseases. However, managing these large-scale datasets requires specialized computational tools tailored to organize and analyze the extensive data. GPF (Genotypes and Phenotypes in Families) is an open-source platform ( https://github.com/iossifovlab/gpf ) that manages genotypes and phenotypes derived from collections of families. The GPF interface allows interactive exploration of genetic variants, enrichment analysis for de novo mutations, and phenotype/genotype association tools. In addition, GPF allows researchers to share their data securely with the broader scientific community. GPF is used to disseminate two large-scale family collection datasets (SSC, SPARK) for the study of autism funded by the SFARI foundation. However, GPF is versatile and can manage genotypic data from other small or large family collections. Our GPF-SFARI GPF instance ( https://gpf.sfari.org/ ) provides protected access to comprehensive genotypic and phenotypic data for the SSC and SPARK. In addition, GPF-SFARI provides public access to an extensive collection of de novo mutations identified in individuals with autism and related disorders and to gene-level statistics of the protected datasets characterizing the genes' roles in autism. Here, we highlight the primary features of GPF within the context of GPF-SFARI.

Portal-site epinephrine injections improve visualisation in arthroscopic rotator cuff repair

OBJECTIVES

The aim of this study was to evaluate if portal-site injections of 1:200,000 epinephrine improve intraoperative visualisation in arthroscopic rotator cuff repair.

METHODS

Patients with partial-thickness supraspinatus tears were selected for the study. They were assigned consecutive numbers and were divided into two groups-control group and intervention group. The surgeries were done by a single surgeon. Every odd-numbered patient was injected. Johnson's visibility classification, surgeon 5-point ordinal Likert scale (LS), and other parameters were recorded.

RESULTS

A total of 221 participants (58.4 ​± ​6.1 years) were selected. Intraoperative visibility was better in the intervention group according to Johnson's classification-satisfactory visibility was achieved in 68 of 110 patients (62%, control group) compared to 89 of 111 patients (80%) (p ​= ​0.003). Surgeon LS was superior in the intervention group, with a notable decrease in worsened visibility cases. The operative time did not alter statistically significantly-82.2 ​± ​14.4 ​min for the control group, compared to 80.9 ​± ​10.8 ​min in the intervention group (p ​= ​0.056). No injection-associated complications were recorded.

CONCLUSIONS

Portal-site injection of diluted epinephrine solution is safe and improves intraoperative visualisation in arthroscopic rotator cuff repair. This addition does not increase operative time.

LEVEL OF EVIDENCE

Level 3, case-control study.

Lateral ulnar collateral ligament reconstruction enhancing secondary stabilizers in chronic PLRI of the elbow provides good to excellent clinical results with no recurrent instability

PURPOSE

The adopted treatment for chronic elbow PLRI is lateral ulnar collateral ligament reconstruction. However, the most frequently reported complication after primary reconstruction is recurrent instability - up to 25 %. It was thus hypothesized that enhancing the secondary stabilizers will provide successful results with a lower rate of recurrent instability in comparison to techniques with primary reconstruction only. This study aimed to demonstrate a novel surgical technique involving secondary stabilizers.

METHODS

In this retrospective study of 29 cases with chronic PLRI the mean duration of symptoms was 39.6 ± 4.9 months. The mean age was 47.9 years with mainly male patients. The surgeries were performed by one senior surgeon at a single institution. The Mayo Elbow Performance Score (MEPS) and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH) were recorded.

RESULTS

The mean follow-up was 36.8 ± 7.7 months. The MEPS score improved significantly from 59.8 ± 13.1 to 84.7 ± 7.6 (p < 0.001). 23/29 patients (79.2 %) had converted to good and excellent results (MEPS >75 points). The DASH score improved from 40.8 ± 4.6 to 20.9 ± 7.2 (p < 0.001). The total complication rate was 10.3 % (N = 3). No recurrent instability was recorded in comparison to 12.2 % for primary reconstruction only, as reported in the literature (p < 0.05).

CONCLUSION

Enhancing the secondary stabilizers by utilizing an adjacently located autograft provided good and excellent results with no recurrent instability. This novel surgical procedure is easy to reproduce and provides a safe and reliable alternative in cases of chronic PLRI when compared to techniques with primary reconstruction only.

Copper-Based Nanomaterials for Fine-Pitch Interconnects in Microelectronics

ConspectusNanostructured copper-based materials have emerged as a new generation of robust architectures for realizing high-performing and reliable interconnection in modern electronic packaging. As opposed to traditional interconnects, nanostructured materials offer better compliance during the packaging assembly process. Due to the high surface area-to-volume ratio of nanomaterials, they also enable joint formation by sintering through thermal compression at much lower temperatures compared to bulk counterparts. Nanoporous Cu (np-Cu) films have been employed in electronic packaging as materials that facilitate a chip-to-substrate interconnection, realized by a Cu-on-Cu bonding after sintering.In this Account, we discuss the use of self-supported np-Cu films for low-temperature joint formation. The novelty of this work comes from the incorporation of tin (Sn) into the np-Cu structure, thus ensuring lower sintering temperatures with a goal of producing Cu-Sn intermetallic alloy-based joints between two Cu substrates. The incorporation of Sn is done using an all-electrochemical bottom-up approach that involves the conformal coating of fine-structured np-Cu (initially formed by dealloying of Cu-Zn alloys) with a thin layer of Sn.This Account provides insight on existing technologies for using nanostructured films as materials for interconnects as well as the optimization studies for the Sn-coating processes as a new alternative approach. The applicability of the synthesized Cu-Sn nanomaterials for low-temperature joint formation is also discussed. To realize this new approach, the Sn-coating process is administered by a galvanic pulse plating technique, which is optimized to preserve the porosity in the structure with a Cu/Sn atomic ratio that allows for the formation of the Cu₆Sn₅ intermetallic compound (IMC). Nanomaterials obtained using this approach are subjected to joint formation by sintering at temperatures between 300 and 200 °C under 20 MPa pressure in forming gas atmosphere. Cross-section characterization of the formed joints postsintering reveals densified bonds with minimal porosity that consist predominantly of the Cu₃Sn IMC. Furthermore, these joints are less prone to structural inconsistencies compared to existing joints formed using purely np-Cu. The results presented in this Account provide a glimpse into a facile and cost-effective approach for synthesizing nanostructured Cu-Sn films and illustrate their applicability as new interconnect materials.

Study of the effect of treatment with aqueous extracts by oregano and wild basil on raw poultry meat

The effect of treatment with aqueous antioxidant extracts of oregano (Origanum vulgare L.) and wild basil (Clinopodium vulgare L.) in refrigerated storage of raw poultry meat was studied. Physicochemical analyzes of meat samples were performed - total protein, ash, fat, dry matter, cooking loss and pH value in dynamics. The content of malondialdehyde (MDA) and the protein profile were determined. The microorganisms’ growth rate in meat during storage at 4°C for a period of 14 d was monitored. After the 7th d, the total number of mesophilic microorganisms in the meat samples increased to 7.00 log cfu/g, which is indicative of decay. A significant increase in pH value was observed after 14 d of storage, but there were no significant changes in total protein content and protein profile. In all meat samples, the amounts of MDA on days 7 and 14 were significantly below the thresholds indicated in the literature. Experimental groups treated with extracts showed lower values for MDA content compared to the control, which is an indication of certain inhibition of lipid oxidation processes in meat.

Three-Dimensional Immersive Photorealistic Layered Dissection of Superficial and Deep Back Muscles: Anatomical Study

Introduction

The distinct anatomy of the superficial and deep back muscles is characterized by complex layered courses, fascial planes, specific vascularization, and innervation. Knowledge of these anatomical parameters is important for some surgical approaches, including lumbar disc herniation, cerebrospinal fluid fistula repair, vascularized muscle pedicle flaps, and posterior fossa extra-intracranial bypass. In the present study, we use modern techniques of three-dimensional (3D) surface scanning to help better illustrate the layered anatomy of the back muscles.

Material and methods

We dissected in layers the back muscles of one cadaver. Every step of the dissection was 3D scanned using a technique called photogrammetry, which allows the extraction of 3D data from 2D photographs. The 3D data were processed using Blender software, and the 3D photorealistic models were uploaded to a dedicated website for 3D visualization. This allows users to see the 3D models from every desktop or mobile device, as well as augmented (AR) and virtual reality (VR) formats.

Results

The photorealistic 3D models present the back muscles' anatomy in a volumetric manner, which can be visualized on any computer device. The web 3D features, including AR and VR, allow users to zoom, pan, and rotate the models, which may facilitate learning.

Conclusion

The technology of photorealistic surface scanning, modern 3D visualization possibilities of web-dedicated formats, as well as advances in AR and VR, have the potential to help with a better understanding of complex anatomy. We believe that this opens the field for further research in the field of medical education.

A systematic review of elbow arthroscopy complications : Complications, risk factors, and safety tips

PURPOSE

To determine the complications from elbow arthroscopy for the past 16 years, and to summarize the most reported safety techniques and risk factors.

METHODS

Eligibility criteria included level I to IV evidence articles that were published after 2005 in the English language. Excluded were vet, paediatric, and cadaver studies. Open and arthroscopic-assisted elbow procedures were not included. Two online databases were comprehensively searched (PubMed and PMC) in April 2021. Relevant paper selection was conducted by two independent reviewers. MINORS score, demographic properties, indications, procedure type, complication rates, reoperation rates, reported risk factors, and safety techniques were recorded.

RESULTS

Fifty-two articles met the criteria and were included. No relevant level I to II evidence studies were discovered. The mean age ranged from 31 to 65 years. The average body mass indexes were between 26 and over 40 kg/m². There was a prevalence of male sex (from 50.2 to 79.2%). Most of the studies reported a minimum follow-up (range, 4 weeks-12 months). The most common arthroscopic procedure was debridement (up to 73% in Leong et al.'s study). The average MINORS score was 12 (range, 10-16). The total complications rate ranged from 1.5 to 11%, with a few studies reporting over 25%. Nerve injury rate was 1.26-7.5%. Re-operation rate ranged from none (100 procedures) to 11.8%.

CONCLUSIONS

Elbow arthroscopy is a successful procedure with a low overall complications rate (from 1.5 to 11%), and a low nerve injury rate (from 1.26 to 7.5%). Risk factors include patient-related factors (obesity, female sex, age over 65 years, elevated blood sugar levels, hypercoagulable disorder, tobacco and alcohol use), preoperative elbow impairment/previous surgery, and periprocedural steroid injections. Our review discovered a re-operation rate of 2 to 18%.

A Challenging Case of Using Manta Ray Skin Flaps in a Severe Post-Traumatic First Web Space Contracture

Patient: Male, 36-year-old

Final Diagnosis: Web space contracture

Symptoms: Joint stiffnes • loss of thumb abduction • severe scarring

Medication: —

Clinical Procedure: Contracture release

Specialty: Orthopedics and Traumatology • Plastic Surgery

Pelvic Lymphadenectomy in Gynecologic Oncology-Significance of Anatomical Variations

Pelvic lymphadenectomy is a common surgical procedure in gynecologic oncology. Pelvic lymph node dissection is performed for all types of gynecological malignancies to evaluate the extent of a disease and facilitate further treatment planning. Most studies examine the lymphatic spread, the prognostic, and therapeutic significance of the lymph nodes. However, there are very few studies describing the possible surgical approaches and the anatomical variations. Moreover, a correlation between anatomical variations and lymphadenectomy in the pelvic region has never been discussed in medical literature. The present article aims to expand the limited knowledge of the anatomical variations in the pelvis. Anatomical variations of the ureters, pelvic vessels, and nerves and their significance to pelvic lymphadenectomy are summarized, explained, and illustrated. Surgeons should be familiar with pelvic anatomy and its variations to safely perform a pelvic lymphadenectomy. Learning the proper lymphadenectomy technique relating to anatomical landmarks and variations may decrease morbidity and mortality. Furthermore, accurate description and analysis of the majority of pelvic anatomical variations may impact not only gynecological surgery, but also spinal surgery, urology, and orthopedics.

Corona mortis, aberrant obturator vessels, accessory obturator vessels: clinical applications in gynecology

"Corona mortis " (CMOR) is a heterogeneous and often dubious term that causes much confusion in medical literature, especially in regard to its modern day significance in pelvic surgery. Some authors define CMOR as any abnormal anastomotic vessel between the external iliac and obturator vessels, whereas others define it as any vessel coursing over the superior pubic branch, regardless whether it is a vascular anastomosis, an accessory obturator vessels, an obturator vessel related to the external iliac system or a terminal small vessel. There is no standard classification of CMOR and obturator vessels variations, although there are multitudes of classifications describing the diverse variations in the obturator foramen region. We define accessory obturator, aberrant obturator vessels and CMOR as different structures, as CMOR is an anatomical term that reflects a clinical situation rather than an anatomical structure. A new clinical classification for aberrant, accessory obturator vessels and CMOR is proposed regarding the anatomical variations, and the location of vessels to the deep femoral ring. The clinical significance of accessory obturator, aberrant vessels and CMOR is delineated in oncogynecological and urogynecological surgery.

OPTIMISATION OF ORGANIC SOLVENT EXTRACTION OF TOTAL CAROTENOIDS FROM BULGARIAN TOMATO PROCESSING WASTE

The quantity of tomato wastes combined with beneficial characteristics of components of the wastes justifies the great interest of researchers and manufacturers in extracting of carotenoids from this low cost material. In this study the response surface (RSM) approach and Box-Behnken design (BBD) were used to explore the possibility of modelling and optimisation the organic solvent extraction of total carotenoids from Bulgarian tomato processing waste (TPW).  Bulgarian TPW consists of tomato pomace was used in this study. Dried and ground TPW was plased in the extraction flask and stirred with acetone at various extraction conditions. The extract obtained was vacuum filtered through filter paper and was subjected to spectrophotometrically total carotenoids content determination. A three-variable, three-level BBD of RSM was employed in optimisation the extraction conditions for the highest recovery of total carotenoids from Bulgarian TPW. A response surface quadratic model was developed and statistical analysis was carried out. Data concerning model adequacy tests indicated that the values of R2 and Radj2 for quadratic model were the higest in comparison to the other models. The obtained F-value of 38.65 implies the model was significant (p < 0.05) and could be used for optimisation. The effects of extraction temperature, solvent to solid ratio and extraction time were significant in total carotenoids yield. Total carotenoids content ranged from 9.78 to 25.28 mg/100 g dried TPW. The predicted values of total carotenoids content were closed to the experimental observed values. By use of RSM the optimal extraction conditions were determined as follow: extraction time of 90 min, solvent to solid ratio of 60 mL/g and extraction temperature of 50ºC. The results obtained showed that predicted (28.40 mg/100 g dried TPW) and experimental (28.86±0.92 mg/100 g dried TPW) values of total carotenoids content were not significant different (p > 0.05).

Is the Newly Described Interstitial Network the Anatomical Basis of Acupuncture Meridians? A Commentary

A network passing through interstitial tissues of the human body has been recently described. Despite its functional importance is yet unknown, we try to briefly summarize the known data and to interpret it from the viewpoint of Traditional Chinese medicine. We consider the peculiarities of the interstitium to be the morphological basis of at least some of the known phenomena along acupuncture meridians.

Highly Active and Durable Cu x Au(1-x) Ultrathin-Film Catalysts for Nitrate Electroreduction Synthesized by Surface-Limited Redox Replacement

Cu _x Au_(1-x) bimetallic ultrathin-film catalysts for nitrate electroreduction have been synthesized using electrochemical atomic layer deposition by surface-limited redox replacement of Pb underpotentially deposited layer. Controlled by the ratio of [Cu²⁺] ions and [AuCl₄ ^-] complex in the deposition solution, the alloy film composition (atomic fraction, x in the range of 0.5-1) has been determined by X-ray photoelectron spectroscopy and indirectly estimated by anodic stripping voltammetry. The catalytic activity and durability of Cu _x Au_(1-x) thin films, Cu thin film, and bulk Cu have been studied by one- and multiple-cycle voltammetry. The synthesized Cu _x Au_(1-x) thin films feature up to two times higher nitrate electroreduction activity in acidic solution compared to bulk and thin-film Cu counterparts. Highest activity has been measured with a Cu_0.70Au_0.30 catalyst. Durability tests have demonstrated that Cu thin films undergo rapid deactivation losing 65% of its peak activity for 92 cycles, whereas Cu_0.70Au_0.30 catalysts lose only 45% of their top performance. The significantly better durability of alloy films can be attributed to effective resistance to poisoning and/or hindered dissolution of Cu active centers. It has been also found that both Cu _x Au_(1-x) and pure Cu thin films show best electroreduction activity at lowest pH.

Effects on the quality and health-enhancing properties of industrial onion waste powder on bread

Industrial onion waste powder (IOWP) was used as an additive in wheat flour at different levels: 0, 1, 2, 3, 4 and 5%. The effect of onion waste addition on the mixing properties of the dough and quality of bread was investigated. The mixing properties of the dough were determined by farinograph. The bread were characterized and evaluated for crumb hardness, crumb porosity, sensory properties, dietary fiber, total phenolic content and total flavonoids. DPPH and FRAP assays were carried out to measure antioxidant activity in vitro. The results indicated that IOWP could be used as a potential health-enhancing functional ingredient up to 3% level to produce bread enriched with dietary fiber, total phenolic compounds and total flavonoids, and characterized by high antioxidant activity and acceptable quality.

Posttraumatische Rehabilitation von Patienten aus dem rheumatischen Formenkreis

„Rheumatiker“ haben ein erhöhtes Frakturrisiko. Die chirurgische Versorgung eines akuten Traumas bzw. der eingetretenen Traumafolgen ist aufgrund der schlechten ossären und weichteiligen Gewebestrukturen anspruchsvoll. Das Risiko für perioperative Komplikationen ist erhöht. Die Behandlung von „Rheumatikern“ nach Trauma ist komplex und erfordert eine individuelle multimodale Rehabilitation in spezialisierten Einrichtungen, welche die muskulo-skelettale und systemische Manifestation der Grunderkrankung und der additiv vorliegenden Traumafolgen adressieren kann.

Acupuncture causes serotonin release by mast cells

Mast cells (MCs) are important object in experimental acupuncture due to their putative involvement in local reactions to needling. In the rat, they are shown to contain in their granules, among other tissue mediators, serotonin, also called 5-hydroxytryptamine (5-HT). The aim of this study is to examine the normal distribution of 5-HT-containing MCs in soft tissues of Zusanli (ST36) acupuncture point (acupoint) and their morphological changes caused by experimental acupuncture. We observed 5-HT-immunopositive MCs in the tissues and in the vicinity of the needle tract formed after acupuncture. As a result of acupuncture needling, the tissue integrity is disrupted and certain folds are formed in the direction of the needle tract. Connective tissue in the vicinity of the needle tract gets compressed and displaced, together with the 5-HT-immunoreactive MCs seen there. Some of those 5-HT-immunopositive MCs showed signs of degranulation with numerous discharged granules, some of them found at a considerable distance form the cell. Furthermore, 5-HT-immunopositive MCs are unevenly distributed in soft tissues of ST36 acupoint. Larger numbers of 5-HT-containing MCs were visualized in subcutis and dermis, compared to the observed in striated muscles. Placing the acupuncture needle into the rat skin caused a formation of an apparent needle tract, tissue displacement and degranulation of 5-HT-immunopositive MCs. The demonstrated serotonin release by means of MC degranulation might be involved in the local tissue response to acupuncture.

Abdominal Computed Tomography in Macroglobulinemia (Waldenström's Disease)

The findings at abdominal computed tomography (CT) in a patient with primary macroglobulinemia (Waldenström's disease) are reported. CT was of special value in monitoring the extent of the disease in the abdomen and the response to treatment. At the first examination the patient had changes in both the reticuloendothelial system and the small bowel. The prompt disappearance on treatment of the small bowel changes proves that these changes were due to a high plasma viscosity syndrome. The slow response on the liver, spleen and lymph nodes suggests lymphomatous engagement. Although the primary method to diagnose Waldenström's disease is through laboratory tests, CT is of use in monitoring the abdominal involvement, especially the response to treatment.

Colonic polyp histopathology and location in a community-based sample of older adults

Background

Colorectal cancer and its precursors are highly prevalent in developed countries. Estimates in the available literature for prevalence of right-sided-only lesions vary between 20.5 and 48.1 %, with association with female gender and advancing age. Since the original polyp studies, premalignant potential of sessile serrated adenomas has been described and screening utilization of colonoscopy in men, women, and older adults has increased. This study describes the histopathology and distribution of colorectal polyps by age and gender in the post-screening era.

Methods

A registry of biopsies performed during colonoscopy for adults aged 50+ years in 2002-2012 was created using pathology reports from an independent, regional laboratory. Age, histopathology, and polyp location(s) were included. A subgroup analysis was performed for sessile serrated adenomas for 2007-2012. Distributions of histopathology and polyp location were described by age and gender. Statistical comparisons are made using chi-square tests.

Results

13,881 patients (55.5 % male, 44.5 % female), aged 50-95 years (median = 62) were identified. Most patients (59.9 %) had adenomas. Single and multiple adenomas were more common in men than women (57.7 % vs 42.3 %, p < .0001 and 62.2 % vs 37.8 %, p < .001), and with advancing age (60.4 % for ages 50- < 60, 63.4 % for ages 60- < 70, 65 % for ages 70- < 80, and 68.9 % for ages >80). Villous adenomas (n = 545; 3.6 %), dysplasia (n = 49; 0.4 %), and invasive carcinoma (n = 22; 0.2 %) were rare. Sessile serrated adenomas were uncommon (n = 417, 4.5 %), with greater prevalence in women than men (5.1 % vs 4 %, p = 0.02). Patients aged 70- < 80 were more likely to have multiple polyps than those aged 50- < 60 (OR 1.17, 95 % CI 1.03–1.32, p = 0.018 and OR 1.27, 95 % CI 1.10–1.46, p = .001). Most polyps were from ascending and/or transverse colon (n = 8095; 58.3 %). When location was stratified by sex only, men had more polyps than women at each location except the sigmoid and rectum. Further stratification by age of location and sex revealed statistically significant differences (age 50- < 60, p < .0001, age 60- < 70, p = .0227, age 70- < 80, p = .0298, age 80+, p = .0018).

Conclusions

This large community-based sample contributes to understanding of colonic neoplasia. The high prevalence of right and transverse lesions supports ongoing use of colonoscopy over sigmoidoscopy for screening examinations.

Sensitive imaging of magnetic nanoparticles for cancer detection by active feedback MR

PURPOSE

Sensitive imaging of superparamagnetic nanoparticles or aggregates is of great importance in MR molecular imaging and medical diagnosis. For this purpose, a conceptually new approach, termed active feedback magnetic resonance, was developed.

METHODS

In the presence of the Zeeman field, a dipolar field is induced by the superparamagnetic nanoparticles or aggregates. Such dipolar field creates spatial and temporal (due to water diffusion) variations to the precession frequency of the nearby water ¹ H magnetization. Sensitive imaging of magnetic nanoparticles or aggregates can be achieved by manipulating the intrinsic spin dynamics by selective self-excitation and fixed-point dynamics under active feedback fields.

RESULTS

Phantom experiments of superparamagnetic nanoparticles; in vitro experiments of brain tissue with blood clots; and in vivo mouse images of colon cancers, with and without labeling by magnetic nanoparticles, suggest that this new approach provides enhanced, robust, and positive contrast in imaging magnetic nanoparticles or aggregates for cancer detection.

CONCLUSION

The spin dynamics originated from selective self-excitation and fixed-point dynamics under active feedback fields have been shown to be sensitive to dipolar fields generated by magnetic nanoparticles. Magn Reson Med 74:33-41, 2015. © 2014 Wiley Periodicals, Inc.

Abstract W P190: Emergency Medical Services Protocols for Routing Stroke Patients to Designated Stroke Center Hospitals

Background: Stroke systems of care include routing patients to the nearest designated stroke center hospital, bypassing non-designated hospitals. Routing protocols are implemented at the state or county level and vary in qualification criteria and determination of destination hospital. We surveyed all counties in the state of California for presence and characteristics of their prehospital stroke routing protocols.

Methods: Each county in California was queried for the presence of a stroke routing protocol. These protocols were obtained and reviewed for method of stroke identification and criteria for patient transport to a stroke center.

Results: Thirty-three local EMS agencies (LEMSAs) serve 58 counties in California with populations ranging from 1175 to almost 10 million (mean 642,000), area ranging from 47 to 20,000 sq. mi (mean 2690) and population density 2 to 17,000 persons per sq. mi (mean 661). Fifteen LEMSAs (45%) had stroke routing protocols, covering 23 counties (40%) and 68% of the state population. Counties with protocols had higher population density (1500 vs. 140 persons per sq. mi). All protocols designated a time period from symptom onset to EMS evaluation to qualify for routing, median 3 hr (IQR 2.5-4, range 2 - 8). Twelve of 23 (52%) allowed a maximum transport time of 30 minutes to qualify for diversion. The number of LEMSA-designated stroke hospitals per county in jurisdictions with diversion was median 2 (IQR 0-7, range 0 - 29). In the six counties without designated stroke centers, patients meeting criteria were transported out of county. Stroke identification in the field among diverting LEMSAs was achieved using the CPSS/FAST in 23, the LAPSS in 2, county-specific protocol in 7, and not stated in 1.

Conclusion: California EMS stroke routing protocols cover 68% of the state population and vary in characteristics including activation by symptom onset time and destination facility features, reflecting matching of system design to local geographic resources.

Clinical evaluation of a mobile heart rhythm telemonitoring system

Purpose. To evaluate the clinical applicability of a telemonitoring system: telemetric system for collection and distant surveillance of medical information (TEMEO). Methods. We evaluated 60 patients, applying simultaneously standard Holter ECG and telemonitoring. Two different comparisons were performed: (1) TEMEO ECG with standard 12-lead ECG; (2) TEMEO Holter with standard ECG Holter. Results. We found a very high coincidence rate (99.3%) between TEMEO derived ECGs and standard ECGs. Intraclass correlation coefficient analysis revealed high and significant correlation coefficients regarding average, maximal, and minimal heart rate, % of time in tachycardia, single supraventricular ectopic beats (SVEB), and single and couplets of ventricular ectopic beats (VEB) between Holter ECG and TEMEO derived parameters. Couplets of SVEB were recorded as different by the two monitoring systems, however, with a borderline statistical significance. Conclusions. TEMEO derived ECGs have a very high coincidence rate with standard ECGs. TEMEO patient monitoring provides results that are similar to those derived from a standard Holter ECG.

P2-03-06: Endothelin-1/Endothelin A Receptor Signalling in Breast Cancer

Background: Endothelin-1 (ET-1) and endothelin A receptor (ETAR) are implicated in breast cancer growth and progression. ET-1 is secreted by both tumor cells and stroma (macrophages, endothelial cells). The purpose of this study is to evaluate ET-1/ETAR role on cell proliferation and its effects on EGFR signaling pathway. Materials and Methods: Two breast cancer cell lines: MCF-7 and MDA-MB-231 were stimulated with ET-1. Proliferation of breast cancer cells was analyzed using MTT assay. Protein expression (EGFR, pEGFR, AKT, pAKT, ERK, pERK) was evaluated by Western blot. siRNA knockdown of endothelin A receptor (ETAR) was performed in MCF-7 and MDA-MB-231.

Results: ET-1 stimulated proliferation in both cell lines. Interestingly, at higher ET-1 concentrations cell proliferation was more pronounced in MCF-7 when compared with MDA-MB-231. Stimulation with ET-1 activated EGFR and downstream signaling proteins (pAKT and pERK) in both cell lines. Incubation of breast cancer cells with ET-1 for 48 hours had different effect on total EGFR level: 3 fold increase of total EGFR was seen in MCF-7, while no change was detected in MDA-MB-231. siRNA against ETAR decreased ET-1 induced cell proliferation and reduced total EGFR level in MCF-7.

Conclusions: These observations suggest that ET-1/ETAR plays an important role in survival and proliferation of breast cancer cells. However, those effects are diverse in different subtypes of breast cancer. Our results may represent an improved selective targeted treatment strategy, especially for estrogen receptor positive breast cancer.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-03-06.

All electrochemical fabrication of a platinized nanoporous Au thin-film catalyst

In an effort to decrease the high cost associated with the design, testing, and production of electrocatalysts, a completely electrochemical scheme has been developed to deposit and platinize a nanoporous Au (NPG) based catalyst for formic acid oxidation. The proposed route enables synthesis of an alternative to the most established, nanoparticles based catalysts and addresses issues of the latter associated with either contamination inherent from the synthetic route or poor adhesion to the supporting electrode. The synthetic protocol includes as a first step, electrochemical codeposition of a Au((1-x))Ag(x) alloy in a thiosulfate based electrolyte followed by selective electrochemical dissolution (dealloying) of Ag as the less noble metal, that generates an ultrathin and preferably continuous porous structure featuring thickness of less than 20 nm. NPG is then functionalized with Pt (no thicker than 1 nm) by surface limited redox replacement (SLRR) of underpotentially deposited Pb layer to form Pt-NPG. SLRR ensures complete coverage of the surface with Pt, believed to spread evenly over the NPG matrix. Testing of the catalyst at a proof-of-concept level demonstrates its high catalytic activity toward formic acid oxidation. Current densities of 40-50 mA cm(-2) and mass activities of 1-3 A.mg(-1) (of combined Pt-Au catalyst) have been observed and the Pt-NPG thin films have lasted over 2600 cycles in standard formic acid oxidation testing.

From Au to Pt via surface limited redox replacement of Pb UPD in one-cell configuration

This work is aimed at developing a protocol based on surface limited redox replacement (SLRR) of underpotentially deposited (UPD) Pb layers for the growth of epitaxial and continuous Pt thin films on polycrystalline and single crystalline Au surfaces. Different from previously reported papers using SLRR in multiple immersion or flow cell setups, this work explores the one-cell configuration setup as an alternative to improve the efficiency and quality of the growth. Open circuit chronopotentiometry and quartz-crystal microbalance experiments demonstrate steady displacement kinetics and a yield that is higher than the stoichiometric Pt(II)-Pb exchange ratio (1:1). This high yield is attributed to oxidative adsorption of OH(ad) taking place on Pt along with the displacement process. Also, ex situ scanning tunneling microscopy surface characterization reveals after the first replacement event the formation of a dense Pt cluster network that homogenously covers the Au surface. The Pt films grow homogenously with no significant changes in the cluster distribution and surface roughness observed up to 10 successive replacement events. X-ray diffraction analysis shows distinct (111) crystallographic orientation of thicker Pt films deposited on (111) textured Au thin films. Coarse energy dispersive spectroscopy measurements and finer X-ray photoelectron spectroscopy suggest at least 4 atom % Pb incorporating into the Pt layer compared to 13 atom % alloyed Cu when the growth is carried out by SLRR of Cu UPD.

Reproducibility of arterial stiffness indices in different vascular territories and between different observers

BACKGROUND

Increased arterial stiffness (AS) corresponds to an increase in cardiovascular risk. According to recent guidelines AS parameters can be measured on all superficial arteries.

OBJECTIVE

Proceeding from the assumption that viscoelastic properties differ along the arterial tree we set ourselves the task to study the reproducibility of AS indices measured at the common carotid, brachial and femoral arteries.

METHODS

The initial study population included 75 patients (40 ± 14.5 years, 45% males) with a variable distribution of cardiovascular risk factors and without clinical evidence of coronary artery disease. AS parameters were measured at the common carotid, brachial and femoral arteries in all patients using echo-tracking (ET) technique. In a subgroup of 36 patients we tested the interobserver variability in the three vascular territories.

RESULTS

We found that there was a significant correlation between AS indices measured at the common carotid and femoral artery (with the only exception for augmentation index) and that AS parameters measured at the brachial artery did correlate neither with common carotid nor with femoral artery indices. The interobserver variability of ET derived AS parameters was good when they were measured at the carotid or femoral artery. The values of AS indices at the brachial artery however showed considerably lower interobserver agreement.

CONCLUSION

The reproducibility of ET derived AS parameters was good when AS was measured at the common carotid or femoral arteries. On the basis of our results brachial artery is probably not a reliable site for AS measurement.

Common carotid artery hemodynamic factors in patients with cerebral infarctions

The aim of the study was to investigate the changes of the common carotid local hemodynamic factors like wall shear stress and tensile forces in 16 patients with chronic unilateral cerebral infarctions (CUCI), 58 patients with risk factors (RF) for cerebrovascular disease (CVD) and 25 healthy control subjects. The blood flow velocities (BFV), the internal diameters (D) and the vessel wall intima-media thickness (IMT) in the common carotid arteries (CCA) were recorded with color duplex sonography. Systolic (SBP) and diastolic (DBP) blood pressure were measured and mean blood pressure (MBP) was calculated by the formula of Wiggers. Whole blood viscosity (WBV) at the shear rate of 94.5 s-1 was measured on the day of the Doppler ultrasound examination with a rotational viscometer Contraves Low Shear 30. Wall shear stress (WSS), the circumferential wall tension (T) and the tensile stress tau were calculated. The main RF in the patients' groups were hypertension and hyperlipidemia. The SBP, WBV and IMT were significantly increased in the patients with UCI and RF for CVD in comparison to controls. Lower systolic WSS and tau and higher T were established in the patients with UCI. The IMT correlated with WSS and tau. The study confirms the complex influence of the changes in WBV and blood pressure for the development of carotid atherosclerosis.