Ecological roles and importance of sharks in the Anthropocene Ocean.

In ecosystems, sharks can be predators, competitors, facilitators, nutrient transporters, and food. However, overfishing and other threats have greatly reduced shark populations, altering their roles and effects on ecosystems. We review these changes and implications for ecosystem function and management. Macropredatory sharks are often disproportionately affected by humans but can influence prey and coastal ecosystems, including facilitating carbon sequestration. Like terrestrial predators, sharks may be crucial to ecosystem functioning under climate change. However, large ecosystem effects of sharks are not ubiquitous. Increasing human uses of oceans are changing shark roles, necessitating management consideration. Rebuilding key populations and incorporating shark ecological roles, including less obvious ones, into management efforts are critical for retaining sharks' functional value. Coupled social-ecological frameworks can facilitate these efforts.

A preliminary study exploring the effects of transcutaneous spinal cord stimulation on spinal excitability and phantom limb pain in people with a transtibial amputation.

OBJECTIVE: Phantom limb pain (PLP) is debilitating and affects over 70% of people with lower-limb amputation. Other neuropathic pain conditions correspond with increased spinal excitability, which can be measured using reflexes and F-waves. Spinal cord neuromodulation can be used to reduce neuropathic pain in a variety of conditions and may affect spinal excitability, but has not been extensively used for treating phantom limb pain. Here, we propose using a non-invasive neuromodulation method, transcutaneous spinal cord stimulation (tSCS), to reduce PLP and modulate spinal excitability after transtibial amputation. Approach: We recruited three participants, two males (5- and 9-years post-amputation, traumatic and alcohol-induced neuropathy) and one female (3 months post-amputation, diabetic neuropathy) for this 5-day study. We measured pain using the McGill Pain Questionnaire, visual analog scale (VAS), and pain pressure threshold test. We measured spinal reflex and motoneuron excitability using posterior root-muscle (PRM) reflexes and F-waves, respectively. We delivered tSCS for 30 minutes/day for 5 days. Main Results: After 5 days of tSCS, McGill Pain Questionnaire scores decreased by clinically-meaningful amounts for all participants from 34.0±7.0 to 18.3±6.8; however, there were no clinically-significant decreases in VAS scores. Two participants had increased pain pressure thresholds across the residual limb (Day 1: 5.4±1.6 lbf; Day 5: 11.4±1.0 lbf). F-waves had normal latencies but small amplitudes. PRM reflexes had high thresholds (59.5±6.1 µC) and low amplitudes, suggesting that in PLP, the spinal cord is hypoexcitable. After 5 days of tSCS, reflex thresholds decreased significantly (38.6±12.2 µC; p<0.001). Significance: These preliminary results in this non-placebo-controlled study suggest that, overall, limb amputation and PLP may be associated with reduced spinal excitability and tSCS can increase spinal excitability and reduce PLP.

Complications and Learning Curve Associated with an Imageless Burr-Based (CORI) Robotic-Assisted Total Knee Arthroplasty System: Results from First 500 Cases.

Background: The use of robotic-assisted total knee arthroplasty (RA-TKA) is gaining traction. There is evidence to suggest that RA-TKA can help to optimize the precision and accuracy of implant positioning and that there may be protective effects on surrounding bony and soft tissues. Yet, there are important differences between the various RA-TKA systems currently on the market. One such newly introduced RA-TKA system uses imageless technology and performs bony cuts with the use of a burr-based device. The learning curve and complications unique to this system have yet to be assessed. Methods: We evaluated 500 consecutive RA-TKA cases using a newly developed burr-based and imageless system which were done by a single surgeon between the months of October 2021 and February 2023. Operative times were recorded and compared to the previous 150 conventional TKA cases allowing for the learning curve to be calculated using the CUSUM method. Intraoperative and postoperative complications were categorically profiled. Results: The learning curve of this RA-TKA system was found to be 6 cases. Intraoperative complications included unintended bony over resection (n = 3), soft tissue injury (n = 2), and robotic system hardware (n = 2) or software (n = 2) malfunction. Postoperative complications consisted of superficial pin site infection (n = 1) and periprosthetic fracture near the pin sites (n = 1). There were no identified cases of prosthetic joint infection, instability events, or wound complications. Conclusions: The learning curve and the complication profile of a newly introduced imageless and burr-based RA-TKA system were described. This information serves to guide surgeons in adopting this technology and can counsel them regarding the potential pitfalls and challenges associated with its integration into practice. The work sheds light on the complexity and learning curve of the recently released imageless burr-based RA-TKA system. This important information is intended to help surgeons accept this cutting-edge technology by providing advice on any errors and difficulties that can occur when integrating it into clinical practice. This information can help surgeons navigate the complexities of integrating this new burr-based robotic technology into knee replacement procedures, enabling them to make well-informed decisions and receive guidance.

Interaction between microRNA-195 and HuR regulates Paneth cell function in the intestinal epithelium by altering SOX9 translation.

Paneth cells at the bottom of small intestinal crypts secrete antimicrobial peptides, enzymes, and growth factors and contribute to pathogen clearance and maintenance of the stem cell niche. Loss of Paneth cells and their dysfunction occur commonly in various pathologies, but the mechanism underlying the control of Paneth cell function remains largely unknown. Here we identified microRNA-195 (miR-195) as a repressor of Paneth cell development and activity by altering SOX9 translation via interaction with RNA-binding protein HuR. Tissue-specific transgenic expression of miR-195 (miR195-Tg) in the intestinal epithelium decreased the levels of mucosal SOX9 and reduced the numbers of lysozyme-positive (Paneth) cells in mice. Ectopically expressed SOX9 in the intestinal organoids derived from miR-195-Tg mice restored Paneth cell development ex vivo. miR-195 did not bind to Sox9 mRNA but it directly interacted with HuR and prevented HuR binding to Sox9 mRNA, thus inhibiting SOX9 translation. Intestinal mucosa from mice that harbored both Sox9 transgene and ablation of the HuR locus exhibited lower levels of SOX9 protein and Paneth cell numbers than those observed in miR-195-Tg mice. Inhibition of miR-195 activity by its specific antagomir improved Paneth cell function in HuR-deficient intestinal organoids. These results indicate that interaction of miR-195 with HuR regulates Paneth cell function by altering SOX9 translation in the small intestinal epithelium.

A tethering mechanism underlies Pin1-catalyzed proline cis-trans isomerization at a noncanonical site.

The prolyl isomerase Pin1 catalyzes the cis-trans isomerization of proline peptide bonds, a non-covalent post-translational modification that influences cellular and molecular processes, including protein-protein interactions. Pin1 is a two-domain enzyme containing a WW domain that recognizes phosphorylated serine/threonine-proline (pS/pT-P) canonical motifs and an enzymatic PPIase domain that catalyzes proline cis-trans isomerization of pS/pT-P motifs. Here, we show that Pin1 uses a tethering mechanism to bind and catalyze proline cis-trans isomerization of a noncanonical motif in the disordered N-terminal activation function-1 (AF-1) domain of the human nuclear receptor PPARγ. NMR reveals multiple Pin1 binding regions within the PPARγ AF-1, including a canonical motif that when phosphorylated by the kinase ERK2 (pS112-P113) binds the Pin1 WW domain with high affinity. NMR methods reveal that Pin1 also binds and accelerates cis-trans isomerization of a noncanonical motif containing a tryptophan-proline motif (W39-P40) previously shown to be involved in an interdomain interaction with the C-terminal ligand-binding domain (LBD). Cellular transcription studies combined with mutagenesis and Pin1 inhibitor treatment reveal a functional role for Pin1-mediated acceleration of cis-trans isomerization of the W39-P40 motif. Our data inform a refined model of the Pin1 catalytic mechanism where the WW domain binds a canonical pS/T-P motif and tethers Pin1 to the target, which enables the PPIase domain to exert catalytic cis-trans isomerization at a distal noncanonical site.

Regulation of Rubisco activity by interaction with chloroplast metabolites.

Rubisco activity is highly regulated and frequently limits carbon assimilation in crop plants. In the chloroplast, various metabolites can inhibit or modulate Rubisco activity by binding to its catalytic or allosteric sites, but this regulation is complex and still poorly understood. Using rice Rubisco, we characterised the impact of various chloroplast metabolites which could interact with Rubisco and modulate its activity, including photorespiratory intermediates, carbohydrates, amino acids; as well as specific sugar-phosphates known to inhibit Rubisco activity - CABP (2-carboxy-d-arabinitol 1,5-bisphosphate) and CA1P (2-carboxy-d-arabinitol 1-phosphate) through in vitro enzymatic assays and molecular docking analysis. Most metabolites did not directly affect Rubisco in vitro activity under both saturating and limiting concentrations of Rubisco substrates, CO2 and RuBP (ribulose-1,5-bisphosphate). As expected, Rubisco activity was strongly inhibited in the presence of CABP and CA1P. High physiologically relevant concentrations of the carboxylation product 3-PGA (3-phosphoglyceric acid) decreased Rubisco activity by up to 30%. High concentrations of the photosynthetically derived hexose phosphates fructose 6-phosphate (F6P) and glucose 6-phosphate (G6P) slightly reduced Rubisco activity under limiting CO2 and RuBP concentrations. Biochemical measurements of the apparent Vmax and Km for CO2 and RuBP (at atmospheric O2 concentration) and docking interactions analysis suggest that CABP/CA1P and 3-PGA inhibit Rubisco activity by binding tightly and loosely, respectively, to its catalytic sites (i.e. competing with the substrate RuBP). These findings will aid the design and biochemical modelling of new strategies to improve the regulation of Rubisco activity and enhance the efficiency and sustainability of carbon assimilation in rice.

Two Squamomelanocytic Tumors With Dendritic Melanocytes: Thoughts About Origin.

ABSTRACT: Cutaneous malignant squamomelanocytic tumor (SMT) is a rare neoplasm comprising 2 distinct cell populations of squamous cell carcinoma and a second component of either benign or malignant melanocytes. SMT most often presents as a keratotic papule in areas of chronic sun exposure, typically on the head or neck of middle-aged and elderly-aged, White male patient populations. In recent years, there has been an increase in case reports, including a review article published in 2023, identifying a total of 37 cases published in the literature. There are only 3 reported cases in the literature with spindled or dendritic cells in the melanocytic component, as most have been of the epithelioid subtype. Despite the increasing prevalence, the origin and pathophysiology is poorly understood. We report 2 cases of SMT with dendritic melanocytes that are centered around a hair follicle, proposing the theory that these 2 distinct cell types may arise from the hair follicles.

Eosinophilic cystitis-an obscure case of obstructive uropathy in infancy.

We report on an infant with features of intermittent obstructive uropathy, acute kidney injury, hypertension and type 4 renal tubular acidosis (RTA) despite urethral catheterisation and fluid resuscitation. Radiological findings showed upper tract dilatation, likely bilateral vesicoureteric junction obstruction and bladder base thickening which was concerning for possible malignancy. Renal biopsy demonstrated eosinophilic infiltrate, suggestive of kidney involvement. Bladder biopsy was diagnostic for eosinophilic cystitis (EC) showing mature degranulating eosinophils. EC is a rare, easily treatable and important differential of bladder mass in children which may present with an atypical obstructive uropathy. This report adds to the limited literature of this condition within the paediatric population. EC should be considered early in children presenting with eosinophilia, urinary tract obstruction and kidney dysfunction, with uncertain aetiology. This case also highlights the need for detailed imaging, including visualisation of the bladder base, in cases of likely obstructive uropathy.

Shirtsleeves to shirtsleeves in three research generations. A project on the science of science and the exceedingly rare circumstances that sustain research legacies from a mentor to mentee and to theirs: A case study on firearm research.

Background: In the 50 years since public health firearm research began, the decades have witnessed several pioneering investigators, followed by NRA backlash and a CDC funding moratorium, then increasing firearm mortality punctuated by mass shootings, and finally an unprecedented release of funding dedicated for research and to support trainees. Motivated by my own efforts to stay productive in firearm research, by the shirtsleeves-to-shirtsleeves cautionary lesson that wealth - for us this a researcher's funding, infrastructure, and capacity - amassed by one generation will soon diminish, and by my worry that we are not adequately dedicated to growing new investigators, I set out to document researcher lineages in this field. Methods: I created a multigenerational lineage map to find authors using "gun" or "firearm" in the title/abstract as a way to find peer-reviewed publications on firearms as a public health issue. I designated the first author as Gen1 if the manuscript was sole authored or the senior author had never been first author on a firearm publication. I plotted each Gen1 author at the year of their first first-authored publication, and pointed from them to subsequent "first-time first-author investigators" (Gen2) for whom they were senior author, and so on for a Gen2 serving as senior author for a Gen3, and so on in that lineage. Results: Gen1 authors numbered 91 by 2023, the first being Rushforth in 1974.3 Rushforth, 14 years later, produced the first and his only Gen2 author, Paulson,4 who produced no Gen3 authors. The field had produced 6 Gen2 authors when the first Gen3 author appeared in 1993, who produced the first Gen4 author in 1998, 14 years after Kraus5 that initiated that lineage in 1984. To date, only 5 lineages have produced a Gen4 author and among those only one lineage, from Schwab in 2002,6 has produced a Gen5. Twenty-four Gen3 authors have emerged. Only 35% of Gen2 authors produced a Gen3. Conclusion: I hope this motivates years-long strategies to help trainees become established, informed by modeling quantitative and qualitative data to identify characteristics underlying the investigator network related to productivity and shortcomings alike. Without dedication to understand the science of science, shirtsleeves-to-shirtsleeves in three generations may be the fate of firearm research.

Coarse-Grained Simulation of mRNA-Loaded Lipid Nanoparticle Self-Assembly.

Ionizable lipid-containing lipid nanoparticles (LNPs) have enabled the delivery of RNA for a range of therapeutic applications. In order to optimize safe, targeted, and effective LNP-based RNA delivery platforms, an understanding of the role of composition and pH in their structural properties and self-assembly is crucial, yet there have been few computational studies of such phenomena. Here we present a coarse-grained model of ionizable lipid and mRNA-containing LNPs. Our model allows access to the large length- and time-scales necessary for LNP self-assembly and is mapped and parametrized with reference to all-atom structures and simulations of the corresponding components at compositions typical of LNPs used for mRNA delivery. Our simulations reveal insights into the dynamics of self-assembly of such mRNA-encapsulating LNPs, as well as the subsequent pH change-driven LNP morphology and release of mRNA.

CS-PHOC: weekly census counts of Southern Ocean phocids at Cape Shirreff, Livingston Island.

Rapid climatic warming of the Antarctic Peninsula is driving regional population declines and distribution shifts of predators and prey. Affected species include Antarctic ice seals and the southern elephant seal, all of which rely on the peninsula region for critical stages of their life cycle. However, data collection is difficult in this remote region, and therefore long-term time series with which to identify and investigate population trends in these species are rare. We present the Cape Shirreff Phocid Census (CS-PHOC) dataset: weekly counts of phocids (crabeater, leopard, southern elephant, and Weddell seals) hauled out at Cape Shirreff, Livingston Island, during most austral summers since 1997. Data from these censuses were cleaned and aggregated, resulting in robust and comparable count data from 284 censuses across 23 field seasons. The CS-PHOC dataset, which is publicly available through the SCAR Biodiversity Portal, will be updated yearly to provide important information about Southern Ocean phocids in the Antarctic Peninsula.

Psychometric Properties of the Arabic Version of the Pain Resilience Scale among Lebanese Adults with Chronic Musculoskeletal Pain.

Background: The Pain Resilience Scale (PRS), which measures behavioral perseverance and the ability to regulate emotions and cognition despite ongoing pain, lacks an Arabic version. Objectives: This study aimed to translate, culturally adapt, and validate an Arabic version of the Pain Resilience Scale (PRS-A) among Lebanese adults. Methods: Phase 1 involved translation and cross-cultural adaptation of the PRS into Arabic. Phase 2 examined the reliability and validity of the PRS-A. A convenience sample of 154 Lebanese adults with chronic musculoskeletal pain completed the PRS-A and self-report measures of pain catastrophizing, pain self-efficacy, pain intensity and interference, depression and anxiety, and quality of life. Results: The PRS-A yielded a two-factor structure with factor 1 representing "cognitive/affective positivity" and factor 2 representing "behavioral perseverance," accounting for 41.93% and 15.15% of the variance in pain resilience, respectively. Total PRS-A score (M = 33.20 and SD = 9.90) showed significant correlations with pain catastrophizing (M = 27.65, SD = 13.03, and r = -0.52), pain self-efficacy (median = 9.00, IQR = 4, and rho = 0.61), pain intensity (M = 4.50, SD = 2.25, and r = -0.28), pain interference (M = 4.30, SD = 2.89, and r = -0.56), physical (M = 34.95, SD = 9.52, and r = 0.34) and mental (M = 40.08, SD = 12.49, and r = 0.58) health functioning, anxiety (median = 7.00, IQR = 7, and rho = -0.57), and depression (median = 4.00, IQR = 6, and rho = -0.58). PRS-A subscale was also significantly related to all measures except pain intensity, which was correlated with cognitive/affective positivity (r = -0.33) but not behavioral perseverance (r = -0.09). Cronbach's alpha for the PRS-A was 0.87. Conclusion: The PRS-A demonstrated validity and acceptable reliability among Arab-speaking individuals with chronic musculoskeletal pain, suggesting its potential utility for assessing pain resilience within this population.

Gun-free zones and active shootings in the United States: a matched case-control study.

Background: Most Americans believe that gun-free zones make locations more vulnerable to violent crimes, particularly active shootings. However, there is no empirical evidence regarding the impact of gun-free zones on protecting locations from violence. The objective of this study was to estimate the association between gun-free zones and active shootings. Methods: We used a pair-matched case-control study where cases were all US establishments where active shootings occurred between 2014 and 2020, and controls were randomly selected US establishments where active shootings could have but did not occur, pair-matched by establishment type, year, and county. Gun-free status of included establishments was determined via local laws, company policy, news reporting, Google Maps and posted signage, and calling establishments. Findings: Of 150 active shooting cases, 72 (48.0%) were determined to have occurred in a gun-free zone. Of 150 controls where no active shooting occurred, 92 (61.3%) were determined to be gun-free. After accounting for matched pairs, the conditional odds of an active shooting in gun-free establishments were 0.38 times those in non-gun-free establishments, with a 95% confidence interval of 0.19-0.73 (p-value = 0.0038). Several robustness analyses affirmed these findings. Interpretation: It is unlikely that gun-free zones attract active shooters; gun-free zones may be protective against active shootings. This study challenges the proposition of repealing gun-free zones based on safety concerns. Funding: This work was funded in part by the National Collaborative on Gun Violence Research and the Arnold Foundation.

Clinical characteristics and outcomes of adult alveolar rhabdomyosarcoma patients on first-line systemic therapies: A single-institution cohort.

Background: Rhabdomyosarcomas are the most common soft tissue sarcoma in children, and pediatric alveolar rhabdomyosarcoma (ARMS) prognosis has improved based on cooperative studies. However, in adults, ARMS is significantly rarer, has poorer outcomes, and currently lacks optimal treatment strategies. Objective: This study aimed to evaluate the clinical outcome of an adult ARMS population with different front-line systemic chemotherapies and determine if any chemotherapy regimen is associated with improved survival. Materials and methods: This is a retrospective study of histologically confirmed fusion-positive ARMS patients over 18 years of age, who were treated at MD Anderson Cancer Center (MDACC) from 2004 to 2021 and received systemic chemotherapy. Descriptive clinical statistics were performed, including staging, front-line chemotherapy, multimodal therapy usage, response rates, and survival analyses. Results: 49 ARMS patients who received upfront chemotherapy were identified. Locoregional treatments included radiotherapy (RT) alone (29%, n = 14), surgery alone (10%, n = 5), or both (45%, n = 22). Median overall survival (OS) for the entire cohort was 3.6 years, and the overall response rate to systemic therapy was 89%. No chemotherapy regimen showed OS benefit, specifically analyzing the pediatric-based vincristine, actinomycin-D, cyclophosphamide (VAC) or adult-based vincristine, doxorubicin, ifosfamide (VDI) regimens, even when controlled for other clinical risk factors. Conclusion: In this single-center contemporary series, adult ARMS patient outcomes remain poor. There was no statistically significant OS difference in patients who did or did not receive adult or pediatric based ARMS regimens, although a high overall response rate to chemotherapy was seen across the entire cohort. Based on these observations, further randomized prospective studies are necessary to delineate which frontline chemotherapy regimen is most beneficial in this rare adult cancer.

Changes in the tumour microenvironment mark the transition from serous borderline tumour to low-grade serous carcinoma.

Low-grade serous ovarian carcinoma (LGSC) is a rare and lethal subtype of ovarian cancer. LGSC is pathologically, biologically, and clinically distinct from the more common high-grade serous ovarian carcinoma (HGSC). LGSC arises from serous borderline ovarian tumours (SBTs). The mechanism of transformation for SBTs to LGSC remains poorly understood. To better understand the biology of LGSC, we performed whole proteome profiling of formalin-fixed, paraffin-embedded tissue blocks of LGSC (n = 11), HGSC (n = 19), and SBTs (n = 26). We identified that the whole proteome is able to distinguish between histotypes of the ovarian epithelial tumours. Proteins associated with the tumour microenvironment were differentially expressed between LGSC and SBTs. Fibroblast activation protein (FAP), a protein expressed in cancer-associated fibroblasts, is the most differentially abundant protein in LGSC compared with SBT. Multiplex immunohistochemistry (IHC) for immune markers (CD20, CD79a, CD3, CD8, and CD68) was performed to determine the presence of B cells, T cells, and macrophages. The LGSC FAP+ stroma was associated with greater abundance of Tregs and M2 macrophages, features not present in SBTs. Our proteomics cohort reveals that there are changes in the tumour microenvironment in LGSC compared with its putative precursor lesion, SBT. These changes suggest that the tumour microenvironment provides a supportive environment for LGSC tumourigenesis and progression. Thus, targeting the tumour microenvironment of LGSC may be a viable therapeutic strategy. © 2024 The Pathological Society of Great Britain and Ireland.

Authenticity, Well-Being, and Minority Stress in LGB Individuals: A Scoping Review.

In general (i.e. in heteronormative and cisgendered samples), authenticity appears protective against threats to well-being. Authenticity may also, in part, protect well-being against the minority stressors experienced by sexually minoritized (LGB; lesbian, gay, and bisexual) individuals. In this scoping review, we examined the relation between authenticity and well-being in LGB samples experiencing minority stress. We hypothesized that (i) LGB minority stress relates to decreased authenticity (i.e. inauthenticity), (ii) authenticity relates to increased well-being, and (iii) authenticity influences the relation between LGB minority stress and well-being. We identified 17 studies (N = 4,653) from systematic searches across Medline, ProQuest, PsycINFO, and Scopus using terms related to sexual identity, minority stress, authenticity, and well-being. In almost all studies, proximal (but not distal) stress was associated with inauthenticity, and inauthenticity with decreased well-being. In all but one study, the association between proximal stress and well-being was associated with inauthenticity. Although these results are consistent with our hypotheses, the included studies were limited in scope and heterogenous in their methods, instruments, and samples, restricting conclusions regarding mediation or moderation. The results require replication, well-powered direct comparisons between LGB and non-LGB samples, and consideration of the varied ways authenticity can be conceptualized and measured.

Machine learning without a processor: Emergent learning in a nonlinear analog network.

Standard deep learning algorithms require differentiating large nonlinear networks, a process that is slow and power-hungry. Electronic contrastive local learning networks (CLLNs) offer potentially fast, efficient, and fault-tolerant hardware for analog machine learning, but existing implementations are linear, severely limiting their capabilities. These systems differ significantly from artificial neural networks as well as the brain, so the feasibility and utility of incorporating nonlinear elements have not been explored. Here, we introduce a nonlinear CLLN-an analog electronic network made of self-adjusting nonlinear resistive elements based on transistors. We demonstrate that the system learns tasks unachievable in linear systems, including XOR (exclusive or) and nonlinear regression, without a computer. We find our decentralized system reduces modes of training error in order (mean, slope, curvature), similar to spectral bias in artificial neural networks. The circuitry is robust to damage, retrainable in seconds, and performs learned tasks in microseconds while dissipating only picojoules of energy across each transistor. This suggests enormous potential for fast, low-power computing in edge systems like sensors, robotic controllers, and medical devices, as well as manufacturability at scale for performing and studying emergent learning.