A novel in vitro model of clinical cryoablation to investigate the transition zone for focal tumor ablation.

Cryoablation (CA) of solid tumors is highly effective at reducing tumor burden and eliminating small, early stage tumors. However, complete ablation is difficult to achieve and cancer recurrence is a significant barrier to treatment of larger tumors compared to resection. In this study, we explored the relationship between temperature, ice growth, and cell death using a novel in vitro model of clinical CA with the Visual-ICE (Boston Scientific) system, a clinically approved and widely utilized device. We found that increasing the duration of freezing from 1 to 2 min increased ice radius from 3.44 ± 0.13 mm to 5.29 ± 0.16 mm, and decreased the minimum temperature achieved from -22.8 ± 1.3 °C to -45.5 ± 7.9 °C. Furthermore, an additional minute of freezing increased the amount of cell death within a 5 mm radius from 42.5 ± 8.9% to 84.8 ± 1.1%. Freezing at 100% intensity leads to faster temperature drops and a higher level of cell death in the TRAMP-C2 mouse prostate cancer cell line, while lower intensities are useful for slow freezing, but result in less cell death. The width of transition zone between live and dead cells decreased by 0.4 ± 0.2 mm, increasing from one to two cycles of freeze/thaw cycles at 100% intensity. HMGB-1 levels significantly increased with 3 cycles of freeze/thaw compared to the standard 2 cycles. Overall, a longer freezing duration, higher freezing intensity, and more freeze thaw cycles led to higher levels of cancer cell death and smaller transition zones. These results have the potential to inform future preclinical research and to improve therapeutic combinations with CA.

High-efficiency CRISPR gene editing in C. elegans using Cas9 integrated into the genome.

Gene editing in C. elegans using plasmid-based CRISPR reagents requires microinjection of many animals to produce a single edit. Germline silencing of plasmid-borne Cas9 is a major cause of inefficient editing. Here, we present a set of C. elegans strains that constitutively express Cas9 in the germline from an integrated transgene. These strains markedly improve the success rate for plasmid-based CRISPR edits. For simple, short homology arm GFP insertions, 50-100% of injected animals typically produce edited progeny, depending on the target locus. Template-guided editing from an extrachromosomal array is maintained over multiple generations. We have built strains with the Cas9 transgene on multiple chromosomes. Additionally, each Cas9 locus also contains a heatshock-driven Cre recombinase for selectable marker removal and a bright fluorescence marker for easy outcrossing. These integrated Cas9 strains greatly reduce the workload for producing individual genome edits.

Prenatal diagnosis of Hartsfield syndrome with a novel genetic variant.

A G2P0, 24-year-old woman presented at 17 weeks 3 days gestation for a fetal anatomy scan. Ultrasound identified bilateral upper and lower extremity ectrodactyly, semilobar holoprosencephaly, midface hypoplasia, and cleft lip and palate. Amniocentesis for a chromosome microarray demonstrated no significant copy number changes. Whole exome sequencing was subsequently completed, which revealed a de novo, likely pathogenic variant in FGFR1, c.2044G>A (D682N), consistent with FGFR1-related Hartsfield syndrome. This case highlights the first presumed molecularly confirmed prenatal diagnosis of Hartsfield syndrome and identifies a new pathogenic variant.

Public perspective on medications to delay Alzheimer's disease symptoms.

Disease-modifying treatments for Alzheimer's disease are emerging. Our research examined how personal risk for AD may influence intentions to ask for medications to delay symptoms of AD, and how the availability of such medications impacts interest in AD-related genetic testing. Invitations to a web-based survey were posted on social media sites. Respondents were sequentially assigned to imagine that they had a 5%, 15%, or 35% chance of developing AD. They were then provided a hypothetical scenario describing a medication that delayed AD symptoms. After reporting intentions to ask for the medication, respondents were asked about their interest in genetic testing to predict AD risk. Data from 310 individuals were analyzed. Intentions to ask for a preventative medication were greater for respondents presented AD risks of 35% compared to risks of 15% and 5% (86% vs. 66% vs. 62%, respectively, p < 0.001). The proportion who would ask for genetic susceptibility testing increased from 58% to 79% when respondents were told to imagine that a medication that delayed AD symptoms existed (p < 0.001). Findings suggest that individuals who know they have an increased risk for AD are more likely pursue medications to delay onset of disease symptoms, and the availability of AD-delaying treatments will increase interest in associated genetic testing. Findings provide insight about who will pursue emerging preventative medications, including individuals for whom the medications may be inappropriate, and the impact on genetic test utilization.

GLP-1 receptor signaling in the laterodorsal tegmental nucleus attenuates cocaine seeking by activating GABAergic circuits that project to the VTA.

An emerging preclinical literature suggests that targeting central glucagon-like peptide-1 receptors (GLP-1Rs) may represent a novel approach to treating cocaine use disorder. However, the exact neural circuits and cell types that mediate the suppressive effects of GLP-1R agonists on cocaine-seeking behavior are largely unknown. The laterodorsal tegmental nucleus (LDTg) expresses GLP-1Rs and functions as a neuroanatomical hub connecting the nucleus tractus solitarius (NTS), the primary source of central GLP-1, with midbrain and forebrain nuclei known to regulate cocaine-seeking behavior. The goal of this study was to characterize the role of LDTg GLP-1R-expressing neurons and their projections to the ventral tegmental area (VTA) in the reinstatement of cocaine-seeking behavior, an animal model of relapse. Here, we showed that administration of the GLP-1R agonist exendin-4 (Ex-4) directly into the LDTg significantly attenuated cocaine seeking at a dose that did not affect sucrose seeking, ad libitum food intake, or body weight. In addition, our studies revealed that selectively activating NTS-to-LDTg circuits attenuated cocaine seeking via a GLP-1R-dependent mechanism. We also demonstrated, for the first time, that GLP-1Rs are expressed primarily on GABAergic neurons in the LDTg and that the efficacy of Ex-4 to reduce cocaine seeking depends, in part, on activation of LDTg-to-VTA GABAergic projections. Taken together, these studies identify a central mechanism by which Ex-4 attenuates cocaine seeking and highlight GABAergic GLP-1R-expressing circuits in the midbrain as important anti-craving pathways in regulating cocaine craving-induced relapse.

Surgical Techniques for the Repair of Webbed Neck: A Scoping Review.

Webbed neck is a rare condition characterized by bilateral subcutaneous bands, which extend from approximately the mastoid to the acromion. Given its rarity, the literature lacks a review of the techniques used in the repair of this condition. We performed a scoping review to define and summarize the surgical techniques been used in the treatment of webbed neck, with the goal of better equipping the surgeons' armamentarium. Two databases, PubMed and Scopus, were searched from inception through December 27, 2021. Studies were considered for inclusion if they (1) described the webbed neck condition and (2) reported results of surgical correction of this condition. Surgical outcomes and follow-up durations were reported as available. Twenty-two manuscripts were analyzed and included data on 60 patients. The most common syndrome associated with webbed neck was Turner syndrome (48 patients). The most frequently documented procedure technique was a Z-Plasty (38 patients). Other procedures described included: butterfly correction, V-Y Plasty, posterior cervical lift, skin excision, tissue expansion plus skin excision, T to M rearrangement, and subcutaneous fascial excision. Documented complications included hypertrophy of procedure scars or webbed neck recurrence. In summary, we present the first full literature review of the surgical techniques used in the repair of webbed neck. When selecting the technique for repair of the webbed neck, function and cosmesis are important considerations. Future studies should collect standardized outcomes data to appropriately assess and compare the described procedures.

Calcineurin Promotes Neuroplastic Changes in the Amygdala Associated with Weakened Cocaine-Cue Memories.

Interfering with memory reconsolidation or inducing memory extinction are two approaches for weakening maladaptive memories in disorders such as addiction and post-traumatic stress disorder. Both extinction and reconsolidation are regulated by intracellular protein kinases and phosphatases, and interfering with these signaling molecules can alter memory strength. The calcium-dependent protein phosphatase, calcineurin (CaN), has been implicated in both the consolidation and extinction of fear memories. However, the role of CaN in regulating drug-cue associative memories has not been investigated. Prior studies have demonstrated that plasticity at thalamo-lateral amygdala (T-LA) synapses is critically involved in the regulation of cocaine-cue memories. Therefore, in the present study, we tested the effects of LA administration of an activator of CaN, chlorogenic acid (CGA), on behavioral and electrophysiological indices of cocaine cue memory reconsolidation and extinction. Male, Sprague-Dawley rats were trained to self-administer cocaine paired with an audiovisual cue. The cue memory was then either briefly reactivated, extinguished, or not manipulated, followed immediately by LA infusion of CGA. Rats were tested 24 h later for cue-induced reinstatement, or LA slices were prepared for electrophysiological recordings. We found that intra-LA infusions of CGA following cue extinction or reconsolidation reduced cue-induced reinstatement, which was blocked by co-infusion of the CaN inhibitor, FK-506. Similarly, CGA infusions following cue re-exposure significantly attenuated EPSC amplitude at T-LA synapses, suggesting that CaN affects cocaine-cue memory reconsolidation and extinction by altering T-LA synaptic strength. Therefore, CaN signaling in the LA may represent a novel target for disrupting cocaine-associated memories to reduce relapse.SIGNIFICANCE STATEMENT Repetitive drug use induces synaptic plasticity that underlies the formation of long-lasting associative memories for environmental cues paired with the drug. We previously identified thalamo-amygdala synapses (T-LA) that project via the interal capsule, as an important locus for the regulation of cocaine-cue memories. These synapses are strengthened by repeated cocaine-cue pairings, but this is reversed by extinction training or by optogenetic induction of in vivo long-term depression (LTD). Here, we demonstrate that activating calcineurin, a calcium-dependent phosphatase, following the reactivation or extinction of a cocaine-cue memory, induces LTD-like changes at T-LA synapses, and a corresponding decrease in cue-induced reinstatement, suggesting that calcineurin may be a potential therapeutic target for relapse prevention.

Post-surgical pyoderma gangrenosum in otherwise healthy patient with history of COVID-19.

There are increasing reports of autoimmune and dermatologic sequelae of COVID-19. We describe an otherwise healthy patient with recent history of serious COVID-19 infection who developed post-surgical pyoderma gangrenosum following bilateral reduction mammoplasty and was successfully treated with infliximab, mycophenolic acid, and corticosteroids. We present this case to highlight the lingering systemic proinflammatory effects of COVID-19 infection that may increase the risk of rare autoimmune complications of surgery. As a complete understanding of the long-term effects of COVID-19 is poorly understood, patients with a history of COVID-19 infection should be appropriately counseled to these possible risks when discussing surgery.

Alcohol and Drug Use While Cycling Significantly Increases the Likelihood of Facial Fractures.

PURPOSE: Substance use, including alcohol and drugs, has been found to amplify the risks associated with cycling. Our purpose was to determine the relationship between alcohol or drug use and facial injuries in a nationwide population of patients experiencing cycling trauma. METHODS: The authors report a cross-sectional study of patients reported to the National Electronic Injury Surveillance System from January 1, 2019 to December 31, 2019, in the United States. Patients were included in our study if they were evaluated in the emergency department for a cycling-related injury. Primary outcome was facial injury. RESULTS: There were a total of 6499 adult patients who experience an injury after cycling trauma reported by the National Electronic Injury Surveillance System-participating emergency departments during the study period. A total of 553 (553/6499; 8.5%) patients had a facial injury and 82 patients with facial injuries had alcohol/drug use recorded (82/553; 14.8%). The proportion of males with facial injuries was higher in the alcohol/drug group than the no alcohol/drug group (86.6% versus 76.4%, respectively; P = 0.04). Injured cyclists in the alcohol/drug group experienced greater odds of sustaining a facial injury (odds ratio: 2.21, 95% confidence interval: 1.71-2.84, P < 0.0001) and a facial fracture (odds ratio: 2.75, 95% confidence interval: 1.83-4.13, P < 0.0001) than injured cyclists in the no alcohol/drug group. CONCLUSIONS: Substance use while cycling is not safe and significantly increases the likelihood of a facial injury and of facial fractures. This prevalence of injuries would suggest that cycling under the influence should always be illegal, and the law strictly enforced.

Management of surgical soft tissue defects of the lower extremities.

Management of post-operative soft-tissue defects on the lower legs is challenging owing to arterial and venous insufficiency, poor skin quality including epidermal and dermal atrophy, insufficient tissue laxity, and increased risk of infection. This paper highlights the management of post-operative soft-tissue defects on the lower extremity that cannot be closed primarily or by reconstruction with a local flap. A systematic review of the literature was performed using the National Library of Medicine (NLM) PubMed online database. Articles were included if they reported the management of post-operative lower extremity soft-tissue defects with secondary intention healing, full-thickness skin graft, split-thickness skin grafts, or skin substitutes. Sixty-three articles were included for analysis. There are several options for managing surgical defects on the lower legs and the method chosen should depend on various factors, including the quality of the skin, vascularity and size of the defect, medical history of the patient, and the experience of the surgeon.

Microfluidics for the study of mechanotransduction.

Mechanical forces regulate a diverse set of biological processes at cellular, tissue, and organismal length scales. Investigating the cellular and molecular mechanisms that underlie the conversion of mechanical forces to biological responses is challenged by limitations of traditional animal models and in vitro cell culture, including poor control over applied force and highly artificial cell culture environments. Recent advances in fabrication methods and material processing have enabled the development of microfluidic platforms that provide precise control over the mechanical microenvironment of cultured cells. These devices and systems have proven to be powerful for uncovering and defining mechanisms of mechanotransduction. In this review, we first give an overview of the main mechanotransduction pathways that function at sites of cell adhesion, many of which have been investigated with microfluidics. We then discuss how distinct microfluidic fabrication methods can be harnessed to gain biological insight, with description of both monolithic and replica molding approaches. Finally, we present examples of how microfluidics can be used to apply both solid forces (substrate mechanics, strain, and compression) and fluid forces (luminal, interstitial) to cells. Throughout the review, we emphasize the advantages and disadvantages of different fabrication methods and applications of force in order to provide perspective to investigators looking to apply forces to cells in their own research.

Safe Placement of Intramedullary Nail and Inter-Physician Variability in Guidewire Placement in Retrograde Tibiotalocalcaneal Fusions.

Retrograde tibiotalocalcaneal arthrodesis is a salvage procedure for severe arthrosis and deformity of both the tibiotalar and subtalar joints and requires image-confirmed placement of a retrograde guidewire. The anatomical shape of the calcaneus creates a situation in which guidewire placement can be skewed on imaging based on the angle of either internal or external rotation. As a result, the aims of our study were to (1) determine the optimal angle(s) of rotation required to accurately depict guidewire placement on imaging and (2) evaluate and describe the effects angle of rotation has on physician assessment of guidewire placement. Using a C-arm x-ray, images of cadavers with both correctly and incorrectly placed guidewires were taken at 5° increments of internal and external rotation of the cadaveric lower extremity and assessed for accuracy of guidewire depiction. The images revealed that the correctly placed guidewire appeared displaced medially at angles of 35° and 40° of external rotation. Conversely, the incorrectly placed guidewire appeared to be correctly placed at between 10° and 40° of external rotation. These images were then disseminated to various physicians including orthopedic surgeons and podiatrists to determine the ability of physicians to correctly appreciate guidewire placement. Using the responses from 35 physicians, it was found that certain angles of internal and external rotation preclude physicians from correctly determining guidewire placement. We found, based on chi-square analysis, that we were able to reject our null hypothesis with a p value of <.001 leading to the conclusion that indeed angle of rotation and guidewire placement can lead to false depictions of guidewire placement. In conclusion, our study gave objective measurements to guide foot placement during tibiotalocalcaneal fusion to decrease the risk incorrectly depicted medial guidewire placement and subsequent incorrect intramedullary nail placement.

Axillary Lymphadenectomy and Wound Complications in Implant-Based Breast Reconstruction.

BACKGROUND: The most common method of breast reconstruction in the United States today is implant-based reconstruction. However, reported complication rates are high, from 30% to 50%. Thus, it is important for reconstructive surgeons to identify factors associated with or contributing to wound complications after breast reconstruction. This study sought to identify associations between axillary lymph node dissection and postoperative wound complications in implant-based breast reconstruction. METHODS: A retrospective chart review was performed of subjects undergoing breast oncologic and reconstructive surgery by a single breast surgeon and reconstructive surgeon, respectively, from 2013 to 2016. Medical records were reviewed of 273 subjects with 338 reconstructed breasts. Data were recorded on the extent of axillary node dissection and subsequent wound complications including seroma requiring percutaneous drainage, seroma requiring open drainage, wound dehiscence requiring local wound care, wound dehiscence requiring operative revision, implant exposure, and implant loss. RESULTS: Analysis of the data demonstrated an increase in complication rates with extent of axillary lymph node dissection; however, these rates did not reach statistical significance. Statistically significant associations, however, were identified between wound complication rates and other known risk factors including increasing age and body mass index, as well as smoking status. CONCLUSIONS: Although an association between increasing complication rates and the extent of lymph node dissection has previously been reported, this study failed to demonstrate a statistically significant association with logistic regression analysis.

Cross-Sectional Area Measurement of the Central Tarsometatarsal Articulation: A Review of Computed Tomography Scans.

Currently, disagreement exists regarding the superior method for repairing a ligamentous Lisfranc injury regarding whether to use arthrodesis or open reduction internal fixation. The 2 procedures differ in the amount of articular cartilage destroyed. Arthrodesis removes all the articular cartilage, and open reduction internal fixation places transarticular screws, essentially destroying a portion of cartilage. We performed a review of 30 consecutive computed tomography scans that included both foot length and undamaged first, second, and third tarsometatarsal joints to quantify the amount of articular surface area destroyed by placement of standardized 4-mm diameter screws. Measurements were performed using a freeform tool. The calculated surface area of the screws was subtracted from the measured surface area of the joint to yield the amount of surface area occupied by the screws. Our results demonstrated that the average amount of articular surface area destroyed in the first, second, and third tarsometatarsal joints was 4.87%, 4.79%, and 4.86% respectively, with a standard deviation of <1% for each of the joints. Our results have demonstrated that screw placement accounts for only a small percentage of articular surface destroyed. They also showed that the articular surface damage was comparable among the first 3 tarsometatarsal joints. Additionally, our results were similar to the articular surface area calculated from cadaveric specimens in a previous biomechanical study, demonstrating that computed tomography can allow for reliable and accurate assessments of articular surface areas in the foot.

Basal cell carcinoma with intravascular invasion: A case report and review of the literature.

The significance of basal cell carcinoma (BCC) invading the intravascular space is unknown. We report a case of an infiltrative BCC on the scalp that showed evidence of both intravascular and perineural invasion. The tumor locally recurred in the bone marrow space 4.5 years following the initial procedure. Since recurrence and metastasis of BCC can be delayed for many years, we recommend long term follow-up for tumors showing aggressive features.

Phosphoproteomic Analysis Reveals a Novel Mechanism of CaMKIIα Regulation Inversely Induced by Cocaine Memory Extinction versus Reconsolidation.

UNLABELLED: Successful addiction treatment depends on maintaining long-term abstinence, making relapse prevention an essential therapeutic goal. However, exposure to environmental cues associated with drug use often thwarts abstinence efforts by triggering drug using memories that drive craving and relapse. We sought to develop a dual approach for weakening cocaine memories through phosphoproteomic identification of targets regulated in opposite directions by memory extinction compared with reconsolidation in male Sprague-Dawley rats that had been trained to self-administer cocaine paired with an audiovisual cue. We discovered a novel, inversely regulated, memory-dependent phosphorylation event on calcium-calmodulin-dependent kinase II α (CaMKIIα) at serine (S)331. Correspondingly, extinction-associated S331 phosphorylation inhibited CaMKIIα activity. Intra-basolateral amygdala inhibition of CaMKII promoted memory extinction and disrupted reconsolidation, leading to a reduction in subsequent cue-induced reinstatement. CaMKII inhibition had no effect if the memory was neither retrieved nor extinguished. Therefore, inhibition of CaMKII represents a novel mechanism for memory-based addiction treatment that leverages both extinction enhancement and reconsolidation disruption to reduce relapse-like behavior. SIGNIFICANCE STATEMENT: Preventing relapse to drug use is an important goal for the successful treatment of addictive disorders. Relapse-prevention therapies attempt to interfere with drug-associated memories, but are often hindered by unintentional memory strengthening. In this study, we identify phosphorylation events that are bidirectionally regulated by the reconsolidation versus extinction of a cocaine-associated memory, including a novel site on CaMKIIα. Additionally, using a rodent model of addiction, we show that CaMKII inhibition in the amygdala can reduce relapse-like behavior. Together, our data supports the existence of mechanisms that can be used to enhance current strategies for addiction treatment.

Photoinduced Domain Pattern Transformation in Ferroelectric-Dielectric Superlattices.

The nanodomain pattern in ferroelectric-dielectric superlattices transforms to a uniform polarization state under above-band-gap optical excitation. X-ray scattering reveals a disappearance of domain diffuse scattering and an expansion of the lattice. The reappearance of the domain pattern occurs over a period of seconds at room temperature, suggesting a transformation mechanism in which charge carriers in long-lived trap states screen the depolarization field. A Landau-Ginzburg-Devonshire model predicts changes in lattice parameter and a critical carrier concentration for the transformation.

NDVI as a predictor of canopy arthropod biomass in the Alaskan arctic tundra.

The physical and biological responses to rapid arctic warming are proving acute, and as such, there is a need to monitor, understand, and predict ecological responses over large spatial and temporal scales. The use of the normalized difference vegetation index (NDVI) acquired from airborne and satellite sensors addresses this need, as it is widely used as a tool for detecting and quantifying spatial and temporal dynamics of tundra vegetation cover, productivity, and phenology. Such extensive use of the NDVI to quantify vegetation characteristics suggests that it may be similarly applied to characterizing primary and secondary consumer communities. Here, we develop empirical models to predict canopy arthropod biomass with canopy-level measurements of the NDVI both across and within distinct tundra vegetation communities over four growing seasons in the Arctic Foothills region of the Brooks Range, Alaska, USA. When canopy arthropod biomass is predicted with the NDVI across all four growing seasons, our overall model that includes all four vegetation communities explains 63% of the variance in canopy arthropod biomass, whereas our models specific to each of the four vegetation communities explain 74% (moist tussock tundra), 82% (erect shrub tundra), 84% (riparian shrub tundra), and 87% (dwarf shrub tundra) of the observed variation in canopy arthropod biomass. Our field-based study suggests that measurements of the NDVI made from air- and spaceborne sensors may be able to quantify spatial and temporal variation in canopy arthropod biomass at landscape to regional scales.

Epigenetic inheritance of phenotypes associated with parental exposure to cocaine.

Parental exposure to drugs of abuse induces changes in the germline that can be transmitted across subsequent generations, resulting in enduring effects on gene expression and behavior. This transgenerational inheritance involves a dynamic interplay of environmental, genetic, and epigenetic factors that impact an individual's vulnerability to neuropsychiatric disorders. This chapter aims to summarize recent research into the mechanisms underlying the inheritance of gene expression and phenotypic patterns associated with exposure to drugs of abuse, with an emphasis on cocaine. We will first define the epigenetic modifications such as DNA methylation, histone post-translational modifications, and expression of non-coding RNAs that are impacted by parental cocaine use. We will then explore how parental cocaine use induces heritable epigenetic changes that are linked to alterations in neural circuitry and synaptic plasticity within reward-related circuits, ultimately giving rise to potential behavioral vulnerabilities. This discussion will consider phenotypic differences associated with gestational as well as both maternal and paternal preconception drug exposure and will emphasize differences based on offspring sex. In this context, we explore the complex interactions between genetics, epigenetics, environment, and biological sex. Overall, this chapter consolidates the latest developments in the multigenerational effects and long-term consequences of parental substance abuse.