Functionalized Gold Nanoparticles and Halogen Bonding Interactions Involving Fentanyl and Fentanyl Derivatives.

Fentanyl (FTN) and synthetic analogs of FTN continue to ravage populations across the globe, including in the United States where opioids are increasingly being used and abused and are causing a staggering and growing number of overdose deaths each year. This growing pandemic is worsened by the ease with which FTN can be derivatized into numerous derivatives. Understanding the chemical properties/behaviors of the FTN class of compounds is critical for developing effective chemical detection schemes using nanoparticles (NPs) to optimize important chemical interactions. Halogen bonding (XB) is an intermolecular interaction between a polarized halogen atom on a molecule and e--rich sites on another molecule, the latter of which is present at two or more sites on most fentanyl-type structures. Density functional theory (DFT) is used to identify these XB acceptor sites on different FTN derivatives. The high toxicity of these compounds necessitated a "fragmentation" strategy where smaller, non-toxic molecules resembling parts of the opioids acted as mimics of XB acceptor sites present on intact FTN and its derivatives. DFT of the fragments' interactions informed solution measurements of XB using 19F NMR titrations as well as electrochemical measurements of XB at self-assembled monolayer (SAM)-modified electrodes featuring XB donor ligands. Gold NPs, known as monolayer-protected clusters (MPCs), were also functionalized with strong XB donor ligands and assembled into films, and their interactions with FTN "fragments" were studied using voltammetry. Ultimately, spectroscopy and TEM analysis were combined to study whole-molecule FTN interactions with the functionalized MPCs in solution. The results suggested that the strongest XB interaction site on FTN, while common to most of the drug's derivatives, is not strong enough to induce NP-aggregation detection but may be better exploited in sensing schemes involving films.

Mechanistic Elucidation of Nanomaterial-Enhanced First-Generation Biosensors Using Probe Voltammetry of an Enzymatic Reaction.

The incorporation of nanomaterials (NMs) into biosensing schemes is a well-established strategy for gaining signal enhancement. With electrochemical biosensors, the enhanced performance achieved from using NMs is often attributed to the specific physical properties of the chosen nanocomponents, such as their high electronic conductivity, size-dependent functionality, and/or higher effective surface-to-volume ratios. First generation amperometric biosensing schemes, typically utilizing NMs in conjunction with immobilized enzyme and semi-permeable membranes, can possess complex sensing mechanisms that are difficult to study and challenging to understand beyond the observable signal enhancement. This study shows the use of an enzymatic reaction between xanthine (XAN) and xanthine oxidase (XOx), involving multiple electroactive species, as an electrochemical redox probe tool for ascertaining mechanistic information at and within the modified electrodes used as biosensors. Redox probing using components of this enzymatic reaction are demonstrated on two oft-employed biosensing approaches and commonly used NMs for modified electrodes: gold nanoparticle doped films and carbon nanotube interfaces. In both situations, the XAN metabolism voltammetry allows for a greater understanding of the functionality of the semipermeable membranes, the role of the NMs, and how the interplay between the two components creates signal enhancement.

Abscopal Effect Following Cryoablation in a Patient with Metastatic Breast Cancer.

While breast cancer is a common disease with many available treatment options, many patients still have limited responses, especially those with metastatic breast cancer. Surgery of the primary tumor or metastatic sites is often not part of the treatment regimen for patients with metastatic breast cancer. Cryoablation is a relatively non-invasive procedure that is being investigated for patients with breast cancer. Patients with metastatic breast cancer who are not surgical candidates may derive benefit from cryoablation through the abscopal effect. In this case report, we present a patient with stage IV breast cancer who was treated with cryoablation of the primary breast tumor and showed evidence of an abscopal effect in regional and distant metastases.

Imaging biomarkers for diagnosis and treatment response in patients with lymphedema.

Lymphedema is defined as a dysfunction of the lymphatic system producing an accumulation of lymphatic fluid in the surrounding tissue, as well as edema and fibrosis. A total of 250 million people worldwide are affected by this condition. Greater than 99% of these cases are related to a secondary cause. As there is a lack of curative therapy, the goal involves early diagnosis, in order to prevent the progression of the disease. Additionally, early diagnosis can aid in decreasing the demand for more complex surgical procedures. Currently, there is an impressive breadth of diagnostic tests available for these patients. We aimed to review the available literature in relation to the utilization of imaging biomarkers for the early diagnosis and treatment response in lymphedema.

Simulation in Hand Surgery: A Literature Review.

BACKGROUND: Due to duty hour regulations, patient safety and inadequate operative time simulation have become a necessary part of surgical education and training in residency. Currently, there is no formal adoption of simulators for the use of surgical education or assessment in hand surgery. This literature review analyzes that the simulation techniques established thus far in hand surgery. METHODS: A comprehensive literature search was performed on PubMed. Search results were filtered by title and abstract to isolate articles that were relevant to simulation in hand surgery. Articles that were nonspecific to the hand, non-English and cadaveric were excluded. Additional articles were identified through references from the initial search. RESULTS: A total of 1192 articles were yielded from the initial query. After the application of the inclusion criteria, this was narrowed down to 28 articles. Another 8 additional articles were excluded as they did not pertain to the hand although the simulators could be adapted for hand surgery. A total of 20 articles were included in this study. CONCLUSIONS: Surgical simulation is a growing and essential field of surgical education. Simulators in hand surgery are limited and require further research and validation. Like other surgical subspecialties, hand surgery may benefit from the adoption of an official simulation curriculum for the assessment of residents and enhancement of technical skills.

The Impact of implant-based reconstruction on persistent pain after breast cancer surgery: A systematic review.

INTRODUCTION: With the increasing number of breast cancer survivors and reconstruction operations, persistent pain following breast cancer surgery (PPBCT) and its management is becoming a challenge for plastic surgeons. To date, most studies compared the difference in the level of PPBCT in reconstruction versus nonreconstruction groups. We systematically reviewed the literature to assess the impact of implant-based reconstruction on PPBCT levels. MATERIALS AND METHODS: PubMed, Embase, CINAHL, and Scopus databases were searched for relevant articles. We used five search strategies: (persistent pain after breast cancer surgery AND reconstruction), (chronic postsurgical pain AND breast reconstruction), (Breast Implantation [MeSH Terms] AND "Chronic Pain" [MeSH Terms]), (breast reconstruction AND chronic pain), and (postmastectomy pain syndrome AND breast reconstruction). RESULTS: A total of 2281 articles were detected. After scanning for the title and abstract, full-text articles were reviewed to identify the eligible articles. Eleven articles were included in the final review, with seven of these reporting no increased chance of PPBCT following reconstruction with implants, whereas two articles described lower chances of PPBCT following implant-based reconstruction. CONCLUSION: We discovered that implant-based reconstruction does not increase the risk of PPBCT in comparison to other surgical techniques or mastectomy alone. This relationship may facilitate doctors and their patients in the decision-making of the appropriate reconstruction technique to use. In addition, our results should prompt plastic surgeons to prescribe the same dosage and frequency of analgesics to patients undergoing implant reconstruction as they would to their patients not undergoing reconstruction.

Management of a Primary Retroperitoneal Yolk Sac Tumor.

BACKGROUND Existing literature has detailed occurrences of retroperitoneal yolk sac tumors (YSTs) as the result of metastasis from a primary gonadal site. However, primary retroperitoneal YSTs are extremely rare, thus remaining a challenge to diagnose and treat. We present a complex case of a large primary retroperitoneal YST in a man treated with neoadjuvant chemotherapy followed by surgical resection. CASE REPORT A 31-year-old man presented with a chief symptom of severe lower abdominal pain. Diagnostic imaging revealed a large, rapidly progressing neoplasm in the retroperitoneal region, initially thought to be a sarcoma. However, the pathological results from further biopsies found the mass to be a retroperitoneal YST, which was tethered to a large portion of the small bowel. A testicular ultrasound was used to confirm that the mass was a primary tumor with no origins in the gonads. The tumor progressed to involve several fistulas connected to the small intestine and anterior abdominal wall. The patient was treated with 3 cycles of bleomycin, etoposide, and cisplatin, followed by surgical excision of the residual mass. The patient retained normal gastrointestinal functions, and subsequent imaging revealed no evidence of recurrence 2.5 years following resection. CONCLUSIONS Owing to the rarity of extragonadal primary YSTs, diagnostic and treatment standards have not yet been sufficiently explored. Our case demonstrates that a combination of chemotherapy and surgical resection should be considered for select patients with primary YST in the retroperitoneal region.

The Emerging Role of Circulating Tumor DNA in the Management of Breast Cancer.

With the incidence of breast cancer steadily rising, it is important to explore novel technologies that can allow for earlier detection of disease as well more a personalized and effective treatment approach. The concept of "liquid biopsies" and the data they provide have been increasingly studied in the recent decades. More specifically, circulating tumor DNA (ctDNA) has emerged as a potential biomarker for various cancers, including breast cancer. While methods such as mammography and tissue biopsies are the current standards for the detection and surveillance of breast cancer, ctDNA analysis has shown some promise. This review discusses the versatility of ctDNA by exploring its multiple emerging uses for the management of breast cancer. Its efficacy is also compared to current biomarkers and technologies.

Inflammatory Pseudotumor Resembling a Malignant Pancreatic Disease Process.

BACKGROUND/AIM: Inflammatory pseudotumors are complex entities given that they carry varying characteristics with a multitude of behaviors that can resemble a malignancy clinically, radiographically, and histologically. PATIENTS AND METHODS: Our case report presents a 65-year-old-female with a history of fever, abdominal pain, and anemia with imaging suggestive of a malignant disease process involving an ill-defined soft tissue mass between the left adrenal gland and pancreatic tail. RESULTS: Following diagnostic laparoscopy with abdominal washings and subsequent open resection of the mass, final pathology revealed multiple specimens demonstrating dense fibrosis with admixed spindled cells and inflammatory cells, an overarching morphology, and an immunohistochemical staining profile consistent with pancreatic inflammatory pseudotumor. CONCLUSION: Inflammatory pseudotumor is a challenging diagnosis and should be included in the differential diagnosis for a patient who presents with nonspecific symptoms and an ill-defined mass on imaging.

DIAGNOSTIC UTILITY OF HUMAN CHORIONIC GONADOTROPIN WASHOUT IN CERVICAL LYMPH NODE FINE-NEEDLE ASPIRATION FOR METASTATIC TESTICULAR CANCER.

OBJECTIVE: This case report will describe the first adjunct use of directly measuring the concentration of human chorionic gonadotropin (HCG) in fine-needle aspiration (FNA) washout for diagnosing metastatic non-semi-nomatous germ cell tumor (NSGCT) of the testicle in a patient with cervical lymphadenopathy. METHODS: We present the clinical, laboratory, imaging, and pathologic findings, along with a review of the literature. RESULTS: A 23-year-old, otherwise healthy man who first presented with left testicular discomfort and swelling was diagnosed with NSGCT after undergoing a left orchiectomy. A few years later, the patient presented with a 2-cm left supraclavicular mass. Upon ultrasound of the thyroid and soft tissues of the neck, a 1-cm left thyroid nodule was revealed, as well as a 2.8-cm left supraclavicular lymph node, which was cystic in nature and worrisome for metastatic disease given the patient's history of metastatic NSGCT. The results of the FNA of the left thyroid nodule were benign, however the results from the supraclavicular mass were nondiagnostic. Due to the nondiagnostic FNA results, another aspiration with cytopathology and HCG evaluation washout was performed. The HCG aspirate came back with a value of 162 mIU/mL, despite the patient's negative serum HCG results. CONCLUSION: This case demonstrates a novel way to diagnose metastatic testicular germ cell tumors utilizing FNA-HCG washout. Future prospective trials are needed to further elucidate this important finding.

A Surgeon Led Clinically Focused Anatomy Course Increases Student Selection of General Surgery As a Career.

OBJECTIVE: This study aims to identify program-specific critical factors in a student's path to general surgery and how different factors contribute to our high rate of matriculation. DESIGN: Semi-structured interviews were conducted focusing on critical factors in student's decision processes to pursue general surgery. Three investigators independently evaluated the transcripts and identified recurring themes based on phenomenological qualitative methods until saturation was achieved. Inter-rater reliability was determined. SETTING: The study took place at Tulane University School of Medicine, an academic medical center in New Orleans, Louisiana. PARTICIPANTS: Current fourth-year students from our medical school, applying into general surgery, were interviewed for the study. RESULTS: Twelve of 21 students were interviewed. The most common factor cited was the positive effect of clinically based anatomy and of having surgeons in anatomy (81%). Other factors mentioned included interest before medical school, clerkship experience, and mentor interactions; Kappa was 0.76 or higher for each theme. CONCLUSIONS: A clinically focused anatomy course led by surgeons at our institution has a significant impact on a general surgery career choice. With the constant evolution of the medical field, understanding what guides students toward a career in general surgery will better assist medical education planners in providing resources that will positively impact future classes.

Early patterns of food intake in an adolescent weight loss trial as predictors of BMI change.

PURPOSE: To determine whether baseline intake or initial changes in intake of fruits (F), vegetables (V), snack foods (SF), and reduced-calorie snack foods (RCSF) during standard behavioral weight loss treatment predict BMI reductions among overweight adolescents. Given conflicting messages between child and adult weight loss interventions, the role of RCSF in adolescent weight control was of particular interest. METHODS: Seventy-two adolescents, 13-16 years old, participating in a 16-week behavioral weight loss trial with diet records at baseline and 4 weeks were included. Height and weight were measured at 0 and 16 weeks. Frequency of intake of F, V, SF, and RCSF were obtained from 7-day food records at 0 and 4 weeks. RESULTS: Male gender, higher initial frequency of intake of V and increased frequency of intake of F and RCSF over the first 4 weeks of treatment accounted for 43% of the variance in BMI reduction at 16 weeks (p<.001). CONCLUSIONS: Early changes in eating habits, including increased frequency of intake of F and RCSF may promote greater adolescent BMI reductions.

Behavioral weight control treatment with supervised exercise or peer-enhanced adventure for overweight adolescents.

OBJECTIVE: To evaluate the efficacy of behavioral weight control intervention with a peer-enhanced activity intervention versus structured aerobic exercise in decreasing body mass index (BMI) and z-BMI in overweight adolescents. STUDY DESIGN: Participants were randomized to 1 of 2 group-based treatment conditions: (1) cognitive behavioral treatment with peer-enhanced adventure therapy or (2) cognitive behavioral weight control treatment with supervised aerobic exercise. Participants included 118 overweight adolescents, ages 13 to 16 years, and a primary caregiver. Changes in BMI, standardized BMI, percent over BMI, and waist circumference were examined. RESULTS: Analysis of variance on the basis of intent-to-treat indicated significant decreases in all weight change outcomes at the end of treatment, with significant decreases maintained at the 12-month follow-up. No differences in treatment conditions were observed. Secondary analyses indicated that adherence with attendance and completion of weekly diet records contributed significantly to reductions in BMI. CONCLUSIONS: A cognitive behavioral weight control intervention combined with supervised aerobic exercise or peer-enhanced adventure therapy is equally effective in short-term reduction of BMI and z-BMI in overweight adolescents. Adherence, as measured with session attendance and self-monitoring, is a key dimension of weight change.

Predictors of attrition and weight loss in an adolescent weight control program.

OBJECTIVE: To evaluate demographic and psychosocial predictors of attrition and weight loss in a behaviorally based adolescent weight control trial. METHODS AND PROCEDURES: Adolescents (N = 76) aged 13-16 years and 20-80% overweight (M = 60.56%, s.d. = 15.17%) received standard group-based behavioral treatment as part of a randomized trial comparing different activity interventions for overweight adolescents. Anthropometric and psychosocial measures were obtained at baseline and after the 16-week intervention. RESULTS: Higher parent (P < 0.01) and adolescent BMI (P < 0.05) at baseline, as well as ethnic minority status (P < 0.05) were significantly associated with attrition in univariate analyses. Parent BMI remained the only significant predictor of attrition in multivariate analyses. BMI change for completers (N = 62) was highly variable, ranging from -6.09 to +1.62 BMI units. Male gender (P < 0.01) was a significant predictor of reduction in BMI, whereas not being from an ethnic minority group (P < 0.05) and attendance at group sessions (P = 0.05) were associated with > or = 5% absolute weight loss in multivariate analyses. Absolute weight loss during the first 4 weeks of the program was strongly associated with weight loss (pr = 0.44, P < 0.001) during the remainder of the intervention. Psychosocial variables were unrelated to attrition or treatment outcome. DISCUSSION: These findings highlight the potential importance of attending to parental BMI in efforts to retain adolescent participants in treatment, as well as the need to develop weight control interventions that are more effective for ethnic minority youth.