Utility and usability of laser speckle contrast imaging (LSCI) for displaying real-time tissue perfusion/blood flow in robot-assisted surgery (RAS): comparison to indocyanine green (ICG) and use in laparoscopic surgery.

BACKGROUND: Utility and usability of laser speckle contrast imaging (LSCI) in detecting real-time tissue perfusion in robot-assisted surgery (RAS) and laparoscopic surgery are not known. LSCI displays a color heatmap of real-time tissue blood flow by capturing the interference of coherent laser light on red blood cells. LSCI has advantages in perfusion visualization over indocyanine green imaging (ICG) including repeat use on demand, no need for dye, and no latency between injection and display. Herein, we report the first-in-human clinical comparison of a novel device combining proprietary LSCI processing and ICG for real-time perfusion assessment during RAS and laparoscopic surgeries. METHODS: ActivSight™ imaging module is integrated between a standard laparoscopic camera and scope, capable of detecting tissue blood flow via LSCI and ICG in laparoscopic surgery. From November 2020 to July 2021, we studied its use during elective robotic-assisted and laparoscopic cholecystectomies, colorectal, and bariatric surgeries (NCT# 04633512). For RAS, an ancillary laparoscope with ActivSight imaging module was used for LSCI/ICG visualization. We determined safety, usability, and utility of LSCI in RAS vs. laparoscopic surgery using end-user/surgeon human factor testing (Likert scale 1-5) and compared results with two-tailed t tests. RESULTS: 67 patients were included in the study-40 (60%) RAS vs. 27 (40%) laparoscopic surgeries. Patient demographics were similar in both groups. No adverse events to patients and surgeons were observed in both laparoscopic and RAS groups. Use of an ancillary laparoscopic system for LSCI/ICG visualization had minimal impact on usability in RAS as evidenced by surgeon ratings of device usability (set-up 4.2/5 and form-factor 3.8/5). LSCI ability to detect perfusion (97.5% in RAS vs 100% in laparoscopic cases) was comparable in both RAS and laparoscopic cases. CONCLUSIONS: LSCI demonstrates comparable utility and usability in detecting real-time tissue perfusion/blood flow in RAS and laparoscopic surgery.

Sigma1 Regulates Lipid Droplet-mediated Redox Homeostasis Required for Prostate Cancer Proliferation.

Lipid droplets (LD) are dynamic organelles that serve as hubs of cellular metabolic processes. Emerging evidence shows that LDs also play a critical role in maintaining redox homeostasis and can mitigate lipid oxidative stress. In multiple cancers, including prostate cancer, LD accumulation is associated with cancer aggressiveness, therapy resistance, and poor clinical outcome. Prostate cancer arises as an androgen receptor (AR)-driven disease. Among its myriad roles, AR mediates the biosynthesis of LDs, induces autophagy, and modulates cellular oxidative stress in a tightly regulated cycle that promotes cell proliferation. The factors regulating the interplay of these metabolic processes downstream of AR remain unclear. Here, we show that Sigma1/SIGMAR1, a unique ligand-operated scaffolding protein, regulates LD metabolism in prostate cancer cells. Sigma1 inhibition triggers lipophagy, an LD selective form of autophagy, to prevent accumulation of LDs which normally act to sequester toxic levels of reactive oxygen species (ROS). This disrupts the interplay between LDs, autophagy, buffering of oxidative stress and redox homeostasis, and results in the suppression of cell proliferation in vitro and tumor growth in vivo. Consistent with these experimental results, SIGMAR1 transcripts are strongly associated with lipid metabolism and ROS pathways in prostate tumors. Altogether, these data reveal a novel, pharmacologically responsive role for Sigma1 in regulating the redox homeostasis required by oncogenic metabolic programs that drive prostate cancer proliferation. SIGNIFICANCE: To proliferate, cancer cells must maintain productive metabolic and oxidative stress (eustress) while mitigating destructive, uncontrolled oxidative stress (distress). LDs are metabolic hubs that enable adaptive responses to promote eustress. Targeting the unique Sigma1 protein can trigger distress by disrupting the LD-mediated homeostasis required for proliferation.

Surgical treatment of retrograde peristalsis following laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: Retrograde Roux limb peristalsis following laparoscopic Roux-en-Y gastric bypass is a rare complication that can be difficult to identify. It may present as persistent nausea, vomiting, abdominal pain, or even gastrointestinal bleeding related to an anastomotic ulcer. Upper gastrointestinal (UGI) series is an important diagnostic modality to identify this motility disorder; however, it may not be readily identifiable without specific delayed imaging. The etiology of this phenomenon is unclear, but attributing factors include the presence of ectopic pacemaker cells, variable lengths of the Roux limb and misconstructions. When this problem is identified, revisional surgery is indicated. CASE DESCRIPTION: A 51-y-old female with morbid obesity presented with persistent nausea and vomiting following a laparoscopic gastric bypass. A CT scan showed a dilated Roux limb. Reverse peristalsis from the jejunojejunostomy toward the gastric pouch was identified on a UGI. Two laparoscopic revisions of the jejunojunostomy were attempted to correct this dysfunction. DISCUSSION: An attempt at widening and relaxing the anastomosis was unsuccessful at providing relief of symptoms. A second revision with an anastomosis between the Roux limb and common channel provided long-term improvement. Identifying complications of gastric bypass surgery can be challenging. Imaging studies may be limited, and often diagnostic and revisional surgery is indicated.

Reduction in Opiate Use, Pain, Nausea, and Length of Stay After Implementation of a Bariatric Enhanced Recovery After Surgery Protocol.

PURPOSE: Evaluate adherence to bariatric surgery enhanced recovery after surgery (ERAS) protocols in pre-operative, operative, and post-operative phases, and to compare opiate use, nausea control, and length of stay (LOS) versus historical controls. MATERIALS AND METHODS: A retrospective, observational cohort study was conducted to evaluate adherence to ERAS protocols and compare opiate and antiemetic use, pain intensity, and LOS versus those of traditional care (TC) patients preceding protocol implementation at Erie County Medical Center, a community-based hospital in Buffalo, NY, USA. RESULTS: One hundred ERAS and TC patients were compared. Patients were similar in age (42.5 years), gender (female, ~ 80%), race (~ 80 white), and BMI (47 kg/m2). The primary procedure performed was sleeve gastrectomy (89% ERAS, 86% TC). Protocol adherence was high for ERAS phases: prior to admission (85-98%), pre-operative (96-100%), operative (93-99%), post-anesthesia care unit (PACU) (55-61%), and floor (86-98%). Opiate morphine milligram equivalent (MME) was reduced in ERAS vs. TC in hospital by 73% (43.5 ± 42.4 vs. 160 ± 116; p < 0.001), discharge prescribing by 53% (34.8 ± 38.2 vs. 74 ± 125 MME; p = 0.003), and in total by 69% (78.3 ± 67.5 vs. 252 ± 160; p < 0.001). Despite lower opiate use, ERAS had lower pain intensity entering PACU (1.1 ± 1.8 vs. 1.9 ± 2.6; p < 0.011), leaving PACU (1.7 ± 1.5 vs. 2.9 ± 1.5; p < 0.001), and floor day 0 (5.0 ± 2.1 vs. 5.9 ± 1.8; p < 0.001). Fewer ERAS required antiemetic day 0 (63% vs. 94%; p < 0.001). ERAS were discharged in fewer hours than TC (41.1 ± 15.5 vs. 52.1 ± 18.9 h; p < 0.001). CONCLUSIONS: Bariatric surgery ERAS protocols were implemented with a high rate of adherence and yielded profound reduction in operative and post-operative opiate use while improving pain control and nausea management in hospital and decreasing LOS.

Anticodon loop mutations perturb reading frame maintenance by the E site tRNA.

The ribosomal E site helps hold the reading frame. Certain tRNA mutations affect translation, and anticodon loop mutations can be especially detrimental. We studied the effects of mutations saturating the anticodon loop of the amber suppressor tRNA, Su7, on the ability to help hold the reading frame when in the E site. We also tested three mutations in the anticodon stem, as well as a mutation in the D stem (the "Hirsh" mutation). We used the Escherichia coli RF2 programmed frameshift site to monitor frame maintenance. Most anticodon loop mutations increase frameshifting, possibly by decreasing codon:anticodon stability. However, it is likely that the A site is more sensitive to anticodon loop structure than is the E site. Unexpectedly, the Hirsh mutation also increases frameshifting from the E site. Other work shows that mutation may increase the ability of tRNA to react in the A site, possibly by facilitating conformational changes required for aminoacyl-tRNA selection. We suggest that this property may decrease its ability to bind to the E site. Finally, the absence of the ms(2)io(6)A nucleoside modifications at A37 does not decrease the ability of tRNA to help hold the reading frame from the E site. This was also unexpected because the absence of these modifications affects translational properties of tRNA in A and P sites. The absence of a negative effect in the E site further highlights the differences among the substrate requirements of the ribosomal coding sites.

Haloperidol and Prostate Cancer Prevention: More Epidemiologic Research Needed.

CONTEXT: The antipsychotic drug haloperidol has antiproliferative and growth-inhibiting properties on prostate cancer cell lines in vitro by binding the sigma 1 protein. Evidence is needed regarding a possible preventive association in men. OBJECTIVE: To examine whether our epidemiologic data support an inverse association of haloperidol use with risk of prostate cancer. DESIGN: These case-control analyses used conditional logistic regression to estimate relative risk by odds ratios (ORs) adjusting for race/ethnicity and aspects of medical care related to detection of prostate cancer. We tested 3 other commonly used antipsychotic drugs, risperidone, quetiapine, and olanzapine, for sigma 1 protein binding and inhibition of clonogenic growth of prostate cancer cells. Use of any of these by men was considered use of a comparator drug. MAIN OUTCOME MEASURES: 1) association of haloperidol with prostate cancer; 2) sigma 1 binding and clonogenic growth. RESULTS: Probably owing to small numbers of haloperidol recipients, evidence of a preventive association was inconsistent, depending on the definition of long-term use. If duration of use was greater than 1 year, the odds ratio (OR) was 0.38 (95% confidence interval (CI) = 0.14-1.01) for haloperidol and 0.80 (95% CI = 0.66-0.98) for the comparator drug; if the duration of use was greater than 2 years, the OR was 0.66 (95% CI = 0.24-1.76) for haloperidol and 0.84 (95% CI = 0.66-1.08) for the comparator drug. Unlike haloperidol, risperidone, quetiapine, and olanzapine did not bind sigma 1 or inhibit clonogenic growth. CONCLUSION: Given the laboratory evidence, our ambiguous epidemiologic findings should encourage more epidemiologic evaluation of haloperidol use and risk of prostate cancer. Finding a negative association could be a scientific advance in prostate cancer prevention but would not be sufficient basis for recommending the prescription of haloperidol for that purpose.

A novel multidimensional reinforcement task in mice elucidates sex-specific behavioral strategies.

A large body of work has focused on understanding stimulus-driven behavior, sex differences in these processes, and the neural circuits underlying them. Many preclinical mouse models present rewarding or aversive stimuli in isolation, ignoring that ethologically, reward seeking requires the consideration of potential aversive outcomes. In addition, the context (or reinforcement schedule under) in which stimuli are encountered can engender different behavioral responses to the same stimulus. Thus, delineating neural control of behavior requires a dissociation between stimulus valence and stimulus-driven behavior. We developed the Multidimensional Cue Outcome Action Task (MCOAT) to dissociate motivated action from cue learning and valence in mice. First, mice acquire positive and negative reinforcement in the presence of discrete discriminative stimuli. Next, discriminative stimuli are presented concurrently allowing for parsing innate behavioral strategies based on reward seeking and avoidance. Lastly, responding in the face of punishment is assessed, thus examining  how positive and negative outcomes are relatively valued. First, we identified sex-specific behavioral strategies, showing that females prioritize avoidance of negative outcomes over seeking positive, while males have the opposite strategy. Next, we show that chemogenetically inhibiting D1 medium spiny neurons (MSNs) in the nucleus accumbens-a population that has been linked to reward-driven behavior-reduces positive and increases negative reinforcement learning rates. Thus, D1 MSNs modulate stimulus processing, rather than motivated responses or the reinforcement process itself. Together, the MCOAT has broad utility for understanding complex behaviors as well as the definition of the discrete information encoded within cellular populations.

Small-Molecule Modulators of Sigma1 and Sigma2/TMEM97 in the Context of Cancer: Foundational Concepts and Emerging Themes.

There are two known subtypes of the so-called sigma receptors, Sigma1 and Sigma2. Sigma1 (encoded by the SIGMAR1 gene and also known as Sigma-1 receptor, S1R) is a unique pharmacologically regulated integral membrane chaperone or scaffolding protein that allosterically modulates the activity of its associated proteins. Sigma2, recently identified as transmembrane protein 97 (TMEM97), is an integral membrane protein implicated in cellular cholesterol homeostasis. A number of publications over the past two decades have suggested a role for both sigma proteins in tumor biology. Although there is currently no clinically used anti-cancer drug that targets Sigma1 or Sigma2/TMEM97, a growing body of evidence supports the potential of small-molecule compounds with affinity for these proteins, putative sigma ligands, as therapeutic agents to treat cancer. In preclinical models, these compounds have been reported to inhibit cancer cell proliferation, survival, adhesion, and migration; furthermore, they have been demonstrated to suppress tumor growth, to alleviate cancer-associated pain, and to exert immunomodulatory properties. Here, we will address the known knowns and the known unknowns of Sigma1 and Sigma2/TMEM97 ligand actions in the context of cancer. This review will highlight key discoveries and published evidence in support of a role for sigma proteins in cancer and will discuss several fundamental questions regarding the physiological roles of sigma proteins in cancer and sigma ligand mechanism of action.

Cell-type and projection-specific dopaminergic encoding of aversive stimuli in addiction.

Drug addiction is a major public health concern across the world for which there are limited treatment options. In order to develop new therapies to correct the behavioral deficits that result from repeated drug use, we need to understand the neural circuit dysfunction that underlies the pathophysiology of the disorder. Because the initial reinforcing effects of drugs are dependent on increases in dopamine in reward-related brain regions such as the mesolimbic dopamine pathway, a large focus of addiction research has centered on the dysregulation of this system and its control of positive reinforcement and motivation. However, in addition to the processing of positive, rewarding stimuli, there are clear deficits in the encoding and valuation of information about potential negative outcomes and how they control decision making and motivation. Further, aversive stimuli can motivate or suppress behavior depending on the context in which they are encountered. We propose a model where rewarding and aversive information guides the execution of specific motivated actions through mesocortical and mesolimbic dopamine acting on D1- and D2- receptor containing neuronal populations. Volitional drug exposure alters the processing of rewarding and aversive stimuli through remodeling of these dopaminergic circuits, causing maladaptive drug seeking, self-administration in the face of negative consequences, and drug craving. Together, this review discusses the dysfunction of the circuits controlling different types of aversive learning as well as how these guide specific discrete behaviors, and provides a conceptual framework for how they should be considered in preclinical addiction models.

Cues play a critical role in estrous cycle-dependent enhancement of cocaine reinforcement.

While preclinical work has aimed to outline the neural mechanisms of drug addiction, it has overwhelmingly focused on male subjects. There has been a push in recent years to incorporate females into existing addiction models; however, males and females often have different behavioral strategies, making it important to not only include females, but to develop models that assess the factors that comprise female drug addiction. Traditional self-administration models often include light or tone cues that serve as discriminative stimuli and/or consequent stimuli, making it nearly impossible to disentangle the effects of cue learning, the cues themselves, and acute effects of psychostimulant drugs. To disentangle the interaction between drug-associated cues and the consummatory and appetitive responding driven by cocaine, we have developed a new behavioral procedure that combines Pavlovian-instrumental transfer with behavioral economic analysis. This task can be completed within a single session, allowing for studies looking at estrous cycle stage-dependent effects in intact cycling females, something that has been difficult in the past. In this study, we found no differences in self-administration across the estrous cycle in the absence of cues; however, when cues were introduced, the cues that acquired value during estrus-but not during diestrus or in males-increased motivation. Cues paired during estrus also increased c-fos expression to a greater extent in striatal regions, an effect that may underlie the observed increases in seeking induced by these cues, even weeks later. Together, these data suggest that fundamental differences in the motivational properties of psychostimulant drugs between males and females are complex and are driven primarily by the interaction between drug-associated stimuli and drug effects.

Attention and restoration in Post-RN students.

BACKGROUND: The impact of a restorative intervention using the natural environment on capacity to direct attention and issues that contribute to attention fatigue for diploma-prepared nursing students (Post-RN students) enrolled in a baccalaureate nursing program was examined. METHODS: This study used a quasi-experimental comparison group design. Subjective (Attentional Functional Index) and objective (Finding A's Test and Symbol Digits Modalities Test) measures were employed. RESULTS: Thirty-two students at two universities participated. Results of the split-plot analysis revealed a within-subject effect on the Attentional Functional Index (p < .05), a significant within-subject effect on the Finding A's Test (p < .05), and a significant within- and between-subject effect on the Symbol Digits Modalities Test (p < .05). CONCLUSION: Recognizing and managing attention fatigue throughout the school year may enhance Post-RN students' abilities to direct attention and contribute to an enhanced academic experience.

Genetic analysis of the E site during RF2 programmed frameshifting.

The roles of the ribosomal E site are not fully understood. Prior evidence suggests that deacyl-tRNA in the E site can prevent frameshifting. We hypothesized that if the E-site codon must dissociate from its tRNA to allow for frameshifting, then weak codon:anticodon duplexes should allow for greater frameshifting than stronger duplexes. Using the well-characterized Escherichia coli RF2 (prfB) programmed frameshift to study frameshifting, we mutagenized the E-site triplet to all Unn and Cnn codons. Those variants should represent a very wide range of duplex stability. Duplex stability was estimated using two different methods. Frameshifting is inversely correlated with stability, as estimated by either method. These findings indicate that pairing between the deacyl-tRNA and the E-site codon opposes frameshifting. We discuss the implications of these findings on frame maintenance and on the RF2 programmed frameshift mechanism.

Discrepant views of oncologists and cancer patients on complementary/alternative medicine.

GOALS: Complementary/ alternative medicine (CAM) is widely used by patients but rarely discussed with oncologists. To understand reasons for the communication gap, this study compares physicians and patients on perceived reasons for CAM use and nondisclosure of use, reactions of physicians to disclosure, and expectations for CAM. PATIENTS AND METHODS: Cross-sectional studies assessed 82 physicians (response 68.3%) and 244 of 374 outpatients (response 65.2%) identified as CAM users at the MD Anderson Cancer Center. Data were summarized by frequency and compared using chi-square tests. MAIN RESULTS: Physicians were more likely (p<0.001) than patients to attribute CAM use to hope (chi2=17.7), control (chi2=17.5), incurable disease (chi2=42.8), or a nontoxic approach (chi2=50.9). Both physicians and patients agreed CAM could relieve symptoms/side effects, but physicians were less likely (p<0.001) than patients to expect that CAM improved immunity (chi2=72.2) or quality of life (chi2=17.1), cured disease (chi2=42.5), or prolonged life (chi2=58.4). Physicians and patients responded differently (p<0.005) on reasons for nondisclosure. Physicians believed patients felt CAM discussions were unimportant (chi2=7.9) and physicians would not understand (chi2 =48.1), discontinue treatment (chi2=26.4), discourage or disapprove of the use (chi2=131.7); patients attributed nondisclosure to their uncertainty of its benefit (chi2=10.4) and never being asked about CAM (chi2=9.9) by physicians. Physicians were more likely (chi2=9.5, p<0.002) to warn of risks and less likely (chi2=23.5, p<0.001) to encourage use than patients perceived. CONCLUSION: Oncologists and cancer patients hold discrepant views on CAM that may contribute to a communication gap. Nevertheless, physicians should ask patients about CAM use, discuss possible benefits, and advise of potential risks.