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1.
Nat Metab ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622413

RESUMO

Nuclear receptor corepressors (NCoRs) function in multiprotein complexes containing histone deacetylase 3 (HDAC3) to alter transcriptional output primarily through repressive chromatin remodelling at target loci1-5. In the liver, loss of HDAC3 causes a marked hepatosteatosis largely because of de-repression of genes involved in lipid metabolism6,7; however, the individual roles and contribution of other complex members to hepatic and systemic metabolic regulation are unclear. Here we show that adult loss of both NCoR1 and NCoR2 (double knockout (KO)) in hepatocytes phenocopied the hepatomegalic fatty liver phenotype of HDAC3 KO. In addition, double KO livers exhibited a dramatic reduction in glycogen storage and gluconeogenic gene expression that was not observed with hepatic KO of individual NCoRs or HDAC3, resulting in profound fasting hypoglycaemia. This surprising HDAC3-independent activation function of NCoR1 and NCoR2 is due to an unexpected loss of chromatin accessibility on deletion of NCoRs that prevented glucocorticoid receptor binding and stimulatory effect on gluconeogenic genes. These studies reveal an unanticipated, non-canonical activation function of NCoRs that is required for metabolic health.

2.
Diabetes Care ; 47(5): 810-817, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38502874

RESUMO

OBJECTIVE: To assess associations between distal symmetric polyneuropathy (DSPN) and Diabetes Prevention Program (DPP) treatment groups, diabetes status or duration, and cumulative glycemic exposure approximately 21 years after DPP randomization. RESEARCH DESIGN AND METHODS: In the DPP, 3,234 adults ≥25 years old at high risk for diabetes were randomized to an intensive lifestyle (ILS), metformin, or placebo intervention to prevent diabetes. After the DPP ended, 2,779 joined the Diabetes Prevention Program Outcomes Study (DPPOS). Open-label metformin was continued, placebo was discontinued, ILS was provided in the form of semiannual group-based classes, and all participants were offered quarterly lifestyle classes. Symptoms and signs of DSPN were assessed in 1,792 participants at DPPOS year 17. Multivariable logistic regression models were used to evaluate DSPN associations with treatment group, diabetes status/duration, and cumulative glycemic exposure. RESULTS: At 21 years after DPP randomization, 66% of subjects had diabetes. DSPN prevalence did not differ by initial DPP treatment assignment (ILS 21.5%, metformin 21.5%, and placebo 21.9%). There was a significant interaction between treatment assignment to ILS and age (P < 0.05) on DSPN. At DPPOS year 17, the odds ratio for DSPN in comparison with ILS with placebo was 17.4% (95% CI 3.0, 29.3) lower with increasing 5-year age intervals. DSPN prevalence was slightly lower for those at risk for diabetes (19.6%) versus those with diabetes (22.7%) and was associated with longer diabetes duration and time-weighted HbA1c (P values <0.001). CONCLUSIONS: The likelihood of DSPN was similar across DPP treatment groups but higher for those with diabetes, longer diabetes duration, and higher cumulative glycemic exposure. ILS may have long-term benefits on DSPN for older adults.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Polineuropatias , Humanos , Idoso , Adulto , Hipoglicemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Prevalência , Metformina/uso terapêutico
3.
Front Microbiol ; 15: 1208033, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525072

RESUMO

Cable bacteria embed a network of conductive protein fibers in their cell envelope that efficiently guides electron transport over distances spanning up to several centimeters. This form of long-distance electron transport is unique in biology and is mediated by a metalloprotein with a sulfur-coordinated nickel (Ni) cofactor. However, the molecular structure of this cofactor remains presently unknown. Here, we applied multi-wavelength Raman microscopy to identify cell compounds linked to the unique cable bacterium physiology, combined with stable isotope labeling, and orientation-dependent and ultralow-frequency Raman microscopy to gain insight into the structure and organization of this novel Ni-cofactor. Raman spectra of native cable bacterium filaments reveal vibrational modes originating from cytochromes, polyphosphate granules, proteins, as well as the Ni-cofactor. After selective extraction of the conductive fiber network from the cell envelope, the Raman spectrum becomes simpler, and primarily retains vibrational modes associated with the Ni-cofactor. These Ni-cofactor modes exhibit intense Raman scattering as well as a strong orientation-dependent response. The signal intensity is particularly elevated when the polarization of incident laser light is parallel to the direction of the conductive fibers. This orientation dependence allows to selectively identify the modes that are associated with the Ni-cofactor. We identified 13 such modes, some of which display strong Raman signals across the entire range of applied wavelengths (405-1,064 nm). Assignment of vibrational modes, supported by stable isotope labeling, suggest that the structure of the Ni-cofactor shares a resemblance with that of nickel bis(1,2-dithiolene) complexes. Overall, our results indicate that cable bacteria have evolved a unique cofactor structure that does not resemble any of the known Ni-cofactors in biology.

5.
Ann Vasc Surg ; 102: 47-55, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38307232

RESUMO

BACKGROUND: To analyze surgical site infections (SSIs) after infrainguinal bypass for standard dressings versus closed incision negative pressure wound therapy (ciNPWT) in the Society for Vascular Surgery's Vascular Quality Initiative (VQI). METHODS: We retrospectively analyzed SSI after infrainguinal bypass procedures in the VQI from December 2019 to December 2021 comparing ciNPWT and standard dressings. The primary outcome of any superficial or deep wound infection at 30 days was analyzed in a subset of procedures with 30-day follow-up data (cohort A, n = 1,575). Secondary outcomes including in-hospital SSI, return to the operating room (OR) for infection, and length of stay (LOS) were analyzed for all procedures (cohort B, n = 9,288). Outcomes were analyzed in propensity-matched cohorts. RESULTS: Patients who received ciNPWT (n = 1,389) were more likely to be female (34% vs. 32%, P = 0.04) with a higher rate of smoking history (90% vs. 86%, P = 0.003), diabetes (54% vs. 50%, P = 0.007), obesity (34% vs. 26%, P < 0.001), prior peripheral vascular intervention (57% vs. 51%, P < 0.001), and to prosthetic conduit (55% vs. 48%, P < 0.001) compared to patients with standard dressings (n = 7,899). After propensity matching of cohort A (n = 1,256), the 30-day SSI rate was 4% (12/341) in the ciNPWT and 6% (54/896) in the standard dressing group (P = 0.07, 95% CI 0.03-1.06). In the propensity-matched in-hospital cohort B (n = 5,435), SSI was 3% (35/1,371) in the ciNPWT group and 2% (95/4,064) in the standard dressing group (P = 0.66). There was no difference in the rate of return to the OR for infection, 1% (36/4,064) vs. 1% (19/1,371) (P = 0.13) or LOS, 9.0 vs. 9.0 days (P = 0.86) for the standard versus ciNPWT groups. CONCLUSIONS: In this analysis of the VQI registry, the use of ciNPWT after infrainguinal bypass did not result in a statistically significant decrease in 30-day SSI. We recommend that surgeons consider the use of ciNPWT as part of a bundled process of care for high risk rather than all patients, as it may reduce SSI after infrainguinal bypass.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Ferida Cirúrgica , Humanos , Feminino , Masculino , Tratamento de Ferimentos com Pressão Negativa/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/terapia
6.
Ann Surg ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372276

RESUMO

OBJECTIVE: To characterize the extent of private equity investment affecting surgical care. SUMMARY BACKGROUND DATA: Over the last decade, investor-backed, for-profit private equity groups have invested in healthcare at an unprecedented rate, but the breadth of these investments affecting surgical practice remains largely unknown. METHODS: Four nationally representative databases were used to identify all merger/acquisitions involving surgical practices between 2015-2019, determine private equity investment in those transactions, and link the acquisitions with a physician dataset. RESULTS: 1,542 unique transactions were identified, of which 539 were financed by private equity. 58 transactions were then classified into their respective categories within surgical care: digestive disease, orthopedics, urology, vascular surgery, and plastic/cosmetic surgery. These transactions accounted for 199 practice sites and 1,405 physicians, averaging 24.2 physicians per transaction. Acquisition activity peaked in 2017 with a total of 63 practices involved. Digestive disease, urology, and orthopedic surgery accounted for the most activity. General surgeons were involved in a small share of the digestive disease practice acquisitions. Three "surgery-adjacent" categories were also identified: anesthesiology, ambulatory surgery centers, and surgical staffing firms. Among these, anesthesia was the largest category in terms of practices (194) and physicians (2,660) involved in transactions across the study period. Medical Service Organizations (MSOs) were a key mechanism through which private equity firms invested in surgical care. CONCLUSIONS: Private equity has engaged in substantial investment within surgical specialties, creating increased practice consolidation. These investments affect all levels of medical care and have notable implications for patients, practitioners, and policymakers.

7.
Orthop J Sports Med ; 12(2): 23259671241227224, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38313753

RESUMO

Background: Promising short- and midterm outcomes have been seen after anatomic coracoclavicular ligament reconstruction (ACCR) for chronic acromioclavicular joint (ACJ) injuries. Purpose/Hypothesis: To evaluate long-term outcomes and shoulder-related athletic ability in patients after ACCR for chronic type 3 and 5 ACJ injuries. It was hypothesized that these patients would maintain significant functional improvement and sufficient shoulder-sport ability at a long-term follow-up. Study Design: Case series; Level of evidence, 4. Methods: Included were 19 patients (mean age, 45.9 ± 11.2 years) who underwent ACCR for type 3 or 5 ACJ injuries between January 2003 and August 2014. Functional outcome measures included the American Shoulder and Elbow Surgeons (ASES), Rowe, Constant-Murley, Simple Shoulder Test (SST), and Single Assessment Numeric Evaluation (SANE) scores as well as the visual analog scale (VAS) for pain, which were collected preoperatively and at the final follow-up. Postoperative shoulder-dependent athletic ability was assessed using the Athletic Shoulder Outcome Scoring System (ASOSS). Shoulder activity level was evaluated using the Shoulder Activity Scale (SAS), while the Subjective Patient Outcome for Return to Sports (SPORTS) score was collected to assess the patients' ability to return to their preinjury sporting activity. Results: The mean follow-up time was 10.1 ± 3.8 years (range, 6.1-18.8 years). Patients achieved significant pre- to postoperative improvements on the ASES (from 54.2 ± 22.6 to 83.5 ± 23.1), Rowe (from 66.6 ± 18.1 to 85.3 ± 19), Constant-Murley (from 64.6 ± 20.9 to 80.2 ± 22.7), SST (from 7.2 ± 3.4 to 10.5 ± 2.7), SANE (from 30.1 ± 23.2 to 83.6 ± 26.3), and VAS pain scores (from 4.7 ± 2.7 to 1.8 ± 2.8) (P < .001 for all), with no significant differences between type 3 and 5 injuries. At the final follow-up, patients achieved an ASOSS of 80.6 ± 32, SAS level of 11.6 ± 5.1, and SPORTS score of 7.3 ± 4.1, with no significant differences between type 3 and 5 injuries. Four patients (21.1%) had postoperative complications. Conclusion: Patients undergoing ACCR using free tendon allografts for chronic type 3 and 5 ACJ injuries maintained significant improvements in functional outcomes at the long-term follow-up and achieved favorable postoperative shoulder-sport ability, activity, and return to preinjury sports participation.

8.
Inorg Chem ; 63(6): 2888-2898, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38295440

RESUMO

Late-transition-metal catalysts for polymerization of olefins have drawn a significant amount of attention owing to their ability to tolerate and incorporate polar comonomers. However, a systematic way to experimentally quantify the electronic properties of the ligands used in these systems has not been developed. Quantified ligand parameters will allow for the rational design of tailored polymerization catalysts, which would target specific polymer properties. We report a series of platinum complexes bearing bisphosphinemonoxide ligands, which resemble those used in the polymerization catalysts of Nozaki and Chen. Their electronic properties are investigated experimentally, and trends are rationalized by using computed spectral properties. Benchmarking computational data with known experimental parameters further enhances the utility of both methods for determining optimal ligands for catalytic application.

9.
Int J Biol Macromol ; 260(Pt 1): 129433, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232891

RESUMO

The immunomodulatory properties of the polysaccharides (carrageenan, xylan) from Chondrus crispus (CC), Ahnfeltiopsis devoniensis (AD), Sarcodiotheca gaudichaudii (SG) and Palmaria palmata (PP) algal species were studied. Using RAW264.7 macrophages, we investigated the proliferation and migration capacity of different extracts along with their immunomodulatory activities, including nitric oxide (NO) production, phagocytosis, and secretion of pro-inflammatory cytokines. Polysaccharides from C. crispus and S. gaudichaudii effectively mitigated inflammation and improved scratch-wound healing. Polysaccharide fractions extracted under cold conditions (25 °C), including CC-1A, SG-1A and SG-1B stimulated cell proliferation, while fractions extracted under hot conditions (95 °C), including CC-3A, CC-2B and A. devoniensis (AD-3A), inhibited cell proliferation after 48 h. Furthermore, RAW264.7 cells treated with the fractions CC-3A, AD-1A, and SG-2A significantly reduced LPS-stimulated NO secretion over 24 h. Phagocytosis was significantly improved by treatment with C. crispus (CC-2B, CC-3B) and A. devoniensis (AD-3A) fractions. RAW264.7 cells treated with the CC-2A and SG-1A fractions showed elevated TGF-ß1 expression without affecting TNF-α expression at 24 h. Polysaccharide fractions of A. devoniensis (ι/κ hybrid carrageenan; AD-2A, AD-3A) showed the highest anti-coagulation activity. CC-2A and SG-1A fractions enhanced various bioactivities, suggesting they are candidates for skin-health applications. The carrageenan fractions (CC-3A: λ-, µ-carrageenan, SG-2A: ν-, ι-carrageenan) tested herein showed great potential for developing anti-inflammatory and upscaled skin-health applications.


Assuntos
Chondrus , Algas Comestíveis , Rodófitas , Alga Marinha , Carragenina/farmacologia , Xilanos , Polissacarídeos/farmacologia , Alga Marinha/metabolismo , Anti-Inflamatórios/farmacologia , Anticoagulantes
10.
Geobiology ; 22(1): e12576, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37803496

RESUMO

The great oxidation event (GOE), ~2.4 billion years ago, caused fundamental changes to the chemistry of Earth's surface environments. However, the effect of these changes on the biosphere is unknown, due to a worldwide lack of well-preserved fossils from this time. Here, we investigate exceptionally preserved, large spherical aggregate (SA) microfossils permineralised in chert from the c. 2.4 Ga Turee Creek Group in Western Australia. Field and petrographic observations, Raman spectroscopic mapping, and in situ carbon isotopic analyses uncover insights into the morphology, habitat, reproduction and metabolism of this unusual form, whose distinctive, SA morphology has no known counterpart in the fossil record. Comparative analysis with microfossils from before the GOE reveals the large SA microfossils represent a step-up in cellular organisation. Morphological comparison to extant micro-organisms indicates the SAs have more in common with coenobial algae than coccoidal bacteria, emphasising the complexity of this microfossil form. The remarkable preservation here provides a unique window into the biosphere, revealing an increase in the complexity of life coinciding with the GOE.


Assuntos
Ecossistema , Fósseis , Bactérias , Isótopos de Carbono , Carbono
11.
Arthroscopy ; 40(1): 34-44, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37356505

RESUMO

PURPOSE: To quantify cellular senescence in supraspinatus tendon and subacromial bursa of humans with rotator cuff tears and to investigate the in vitro efficacy of the senolytic dasatinib + quercetin (D+Q) to eliminate senescent cells and alter tenogenic differentiation. METHODS: Tissue was harvested from 41 patients (mean age, 62 years) undergoing arthroscopic rotator cuff repairs. In part 1 (n = 35), senescence was quantified using immunohistochemistry and gene expression for senescent cell markers (p16 and p21) and the senescence-associated secretory phenotype (SASP) (interleukin [IL] 6, IL-8, matrix metalloproteinase [MMP] 3, monocyte chemoattractant protein [MCP] 1). Senescence was compared between patients <60 and ≥60 years old. In part 2 (n = 6) , an in vitro model of rotator cuff tears was treated with D+Q or control. D+Q, a chemotherapeutic and plant flavanol, respectively, kill senescent cells. Gene expression analysis assessed the ability of D+Q to kill senescent cells and alter markers of tenogenic differentiation. RESULTS: Part 1 revealed an age-dependent significant increase in the relative expression of p21, IL-6, and IL-8 in tendon and p21, p16, IL-6, IL-8, and MMP-3 in bursa (P < .05). A significant increase was seen in immunohistochemical staining of bursa p21 (P = .028). In part 2, D+Q significantly decreased expression of p21, IL-6, and IL-8 in tendon and p21 and IL-8 in bursa (P < .05). Enzyme-linked immunosorbent assay analysis showed decreased release of the SASP (IL-6, MMP-3, MCP-1; P = .002, P = .024, P < .001, respectively). Tendon (P = .022) and bursa (P = .027) treated with D+Q increased the expression of COL1A1. CONCLUSIONS: While there was an age-dependent increase in markers of cellular senescence, this relationship was not consistently seen across all markers and tissues. Dasatinib + quercetin had moderate efficacy in decreasing senescence in these tissues and increasing COL1A1 expression. CLINICAL RELEVANCE: This study reveals that cellular senescence may be a therapeutic target to alter the biological aging of rotator cuffs and identifies D+Q as a potential therapy.


Assuntos
Lesões do Manguito Rotador , Humanos , Pessoa de Meia-Idade , Lesões do Manguito Rotador/tratamento farmacológico , Lesões do Manguito Rotador/cirurgia , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Quercetina/farmacologia , Quercetina/uso terapêutico , Metaloproteinase 3 da Matriz/genética , Interleucina-6/metabolismo , Interleucina-8 , Senescência Celular
12.
J Biomed Mater Res B Appl Biomater ; 112(1): e35296, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37702399

RESUMO

This study describes the development and characterization of novel composite scaffolds, made of an alginate-chitosan hydrogel matrix containing eggshell (ES) particles, for bone tissue engineering applications. Scaffolds with ES particles, either untreated or treated with phosphoric acid to create a nanotextured particle surface, were compared to scaffolds without particles. Results indicate that the nanotexturing process exposed occluded ES proteins orthologous to those in human bone extracellular matrix. Scaffolds with ES or nanotextured ES (NTES) particles had a higher porosity (81 ± 4% and 89 ± 5%, respectively) than scaffolds without particles (59 ± 5%) (p = .002 and p < .001, respectively). Scaffolds with NTES particles had a larger median pore size (113 µm [interquartile range [IQ]: 88-140 µm]) than scaffolds with ES particles (94 µm [IQ: 75-112 µm]) and scaffolds without particles (99 µm [IQ: 74-135 µm]) (p < .001 and p = .011, respectively). The compressive modulus of the scaffolds with ES or NTES particles remained low (3.69 ± 0.70 and 3.14 ± 0.62 kPa, respectively), but these scaffolds were more resistant to deformation following maximum compression than those without particles. Finally, scaffolds with ES or NTES particles allowed better retention of human mesenchymal stem cells during seeding (53 ± 12% and 57 ± 8%, respectively, vs. 17 ± 5% for scaffolds without particles; p < .001 in both cases), as well as higher cell viability up to 21 days of culture (67 ± 17% and 61 ± 11%, respectively, vs. 15 ± 7% for scaffolds without particles; p < .001 in both cases). In addition, alkaline phosphatase (ALP) activity increased up to 558 ± 164% on day 21 in the scaffolds with ES particles, and up to 567 ± 217% on day 14 in the scaffolds with NTES particles (p = .006 and p = .002, respectively, relative to day 0). Overall, this study shows that the physicochemical properties of the alginate-chitosan hydrogel scaffolds with ES or NTES particles are similar to those of cancellous bone. In addition, scaffolds with particles supported early osteogenic differentiation and therefore represent a promising new bone substitute, especially for non-load bearing applications.


Assuntos
Quitosana , Alicerces Teciduais , Animais , Humanos , Alicerces Teciduais/química , Osteogênese , Quitosana/química , Hidrogéis/farmacologia , Hidrogéis/química , Casca de Ovo , Regeneração Óssea , Engenharia Tecidual/métodos , Alginatos , Porosidade
13.
Nat Rev Microbiol ; 22(4): 240-254, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37794172

RESUMO

Colorectal cancer (CRC) is a substantial source of global morbidity and mortality in dire need of improved prevention and treatment strategies. As our understanding of CRC grows, it is becoming increasingly evident that the gut microbiota, consisting of trillions of microorganisms in direct interface with the colon, plays a substantial role in CRC development and progression. Understanding the roles that individual microorganisms and complex microbial communities play in CRC pathogenesis, along with their attendant mechanisms, will help yield novel preventive and therapeutic interventions for CRC. In this Review, we discuss recent evidence concerning global perturbations of the gut microbiota in CRC, associations of specific microorganisms with CRC, the underlying mechanisms by which microorganisms potentially drive CRC development and the roles of complex microbial communities in CRC pathogenesis. While our understanding of the relationship between the microbiota and CRC has improved in recent years, our findings highlight substantial gaps in current research that need to be filled before this knowledge can be used to the benefit of patients.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Microbiota , Humanos
14.
Neuropathology ; 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129983

RESUMO

Astroblastoma, MN1-altered, is a rare neoplasm of the central nervous system (CNS). This malignancy shares similar histopathological features with other CNS tumors, including ependymomas, making it challenging to diagnose. DNA methylation profiling is a new and robust technique that may be used to overcome this diagnostic hurdle. We report the case of a now 25-year-old female diagnosed with what was initially called an ependymoma located in the cervical spine at the age of 2 years old. After initial resection, the tumor recurred multiple times and within 2 years of diagnosis had disseminated disease throughout the brain and spinal cord. She has now undergone over two decades of treatment, including multiple surgical resections, radiation therapy, and administration of numerous chemotherapeutic agents. In 2021, the patient presented to our institution with lumbosacral radicular symptoms due to enlarging lesions within the lumbosacral spine. Reexamination of formalin-fixed, paraffin-embedded material from the patient's tumor using genomic DNA methylation profiling resulted in a diagnostic change from grade III anaplastic ependymoma to astroblastoma, MN1-altered. This work describes another confirmed case of astroblastoma, MN1-altered, to the growing body of literature.

15.
Neurosurg Focus Video ; 9(2): V2, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37854648

RESUMO

The video demonstrates an operative approach to a recurrent cervical anaplastic ependymoma. MYCN-amplified anaplastic ependymomas are locally aggressive, recurrent, and have a high risk of iatrogenic injury. In this case, the patient presented with local, aggressive tumor expansion, arachnoid adhesions, and pial invasion ventral to the spinal cord. Subcapsular decompression minimized cord retraction from a dorsal approach. Removal of the tumor capsule was guided by bipolar stimulation paired with neuromonitoring. Local gross-total resection was achieved, and the patient had a postoperative improvement in his neurological deficits and myelopathy.

16.
Nat Commun ; 14(1): 5769, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723139

RESUMO

There is tremendous interest in employing collective excitations of the lattice, spin, charge, and orbitals to tune strongly correlated electronic phenomena. We report such an effect in a ruthenate, Ca3Ru2O7, where two phonons with strong electron-phonon coupling modulate the electronic pseudogap as well as mediate charge and spin density wave fluctuations. Combining temperature-dependent Raman spectroscopy with density functional theory reveals two phonons, B2P and B2M, that are strongly coupled to electrons and whose scattering intensities respectively dominate in the pseudogap versus the metallic phases. The B2P squeezes the octahedra along the out of plane c-axis, while the B2M elongates it, thus modulating the Ru 4d orbital splitting and the bandwidth of the in-plane electron hopping; Thus, B2P opens the pseudogap, while B2M closes it. Moreover, the B2 phonons mediate incoherent charge and spin density wave fluctuations, as evidenced by changes in the background electronic Raman scattering that exhibit unique symmetry signatures. The polar order breaks inversion symmetry, enabling infrared activity of these phonons, paving the way for coherent light-driven control of electronic transport.

17.
Neurosurg Focus ; 55(2): E17, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37527680

RESUMO

OBJECTIVE: The objective of this review was to describe the immunological changes that take place in the dura mater in response to metastatic disease that seeds the CNS. The authors hypothesized that the dura's anatomy and resident immune cell population play a role in enabling metastasis to the brain and leptomeninges. METHODS: An extensive literature search was conducted to identify evidence that supports the dura's participation in metastasis to the CNS. The authors' hypothesis was informed by a recent upsurge in studies that have investigated the dura's role in metastatic development, CNS infections, and autoimmunity. They reviewed this literature as well as the use of immunotherapy in treating brain metastases and how these therapies change the meningeal immune landscape to overcome and reverse tumor-promoting immunosuppression. RESULTS: Evidence suggests that the unique architecture and immune cell profile of the dura, compared with other immune compartments within the CNS, facilitate entry of metastatic tumor cells into the brain. Once these tumor cells penetrate the dural barrier, they propagate an immunosuppressive tumor microenvironment. Therefore, immunotherapy may serve to overcome this immunosuppressive environment and liberate proinflammatory immune cells in an effort to combat metastatic disease. CONCLUSIONS: Within the next few years, the authors expect the addition of several more scientific studies into the literature that further underscore the dura as a chief participant and neuroanatomical barrier in neuro-oncology.


Assuntos
Neoplasias Encefálicas , Neoplasias Supratentoriais , Humanos , Dura-Máter/patologia , Neoplasias Encefálicas/patologia , Encéfalo , Microambiente Tumoral
18.
J Surg Res ; 292: 44-52, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37579715

RESUMO

INTRODUCTION: Parents of children with cancer describe interactions with clinicians as emotionally distressing. Patient engagement in treatment discussions decreases decisional conflict and improves decision quality which may limit such distress. We have shown that parents prefer to engage surgeons by asking questions, but parents may not know what to ask. Question Prompt Lists (QPLs), structured lists of questions designed to help patients ask important questions, have not been studied in pediatric surgery. We developed a QPL designed to empower parents to ask meaningful questions during pediatric surgical oncology discussions. We conducted a mixed methods analysis to assess the acceptability, appropriateness, and feasibility of using the QPL. METHODS: Key stakeholders at an academic children's hospital participated in focus groups to discuss the QPL. Focus groups were recorded and transcribed. Participants were surveyed regarding QPL acceptability, appropriateness, and feasibility. Thematic content analysis of transcripts was performed. RESULTS: Four parents, five nurses, five nurse practitioners, five oncologists, and four surgeons participated. Seven key themes were identified: (1) QPL as a tool of empowerment; (2) stick to the surgical details; (3) QPLs can impact discussion quality; (4) time consuming, but not overly disruptive; (5) parental emotion may impact QPL use; (6) provide QPLs prior to surgical consultation in both print and digital formats; and (7) expansion of QPLs to other disciplines. Over 70% of participants agreed that the QPL was acceptable, appropriate, and feasible. CONCLUSIONS: Our novel QPL is acceptable, appropriate, and feasible to use with parents of pediatric surgical oncology patients.


Assuntos
Neoplasias , Oncologia Cirúrgica , Humanos , Criança , Comunicação , Relações Médico-Paciente , Oncologia , Participação do Paciente , Inquéritos e Questionários
19.
J Phys Chem B ; 127(27): 6091-6101, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37399503

RESUMO

Complementary X-ray absorption fine structure (XAFS) spectroscopy and Raman spectroscopy studies were conducted on several UCl3 concentrations in several chloride salt compositions. The samples were 5% UCl3 in LiCl (S1), 5% UCl3 in KCl (S2), 5% UCl3 in LiCl-KCl eutectic (S3), 5% UCl3 in LiCl-KCl eutectic (S4), 50% UCl3 in KCl (S5), and 20% UCl3 in KCl (S6) molar concentrations. Sample S3 had UCl3 sourced from Idaho National Laboratory (INL), and all other samples were UCl3 sourced from TerraPower. The initial compositions were prepared in an inert and oxygen-free atmosphere. XAFS measurements were performed in the atmosphere at a beamline, and Raman spectroscopy was conducted inside a glovebox. Raman spectra were able to confirm initial UCl3. XAFS and later Raman spectra measured, however, did not correctly match the literature and computational spectra for the prepared UCl3 salt. Rather, the data shows some complex uranium oxychloride phases at room temperature that transition into uranium oxides upon heating. Oxygen pollution due to failure of the sealing mechanism can result in oxidation of the UCl3 salts. The oxychlorides present may be both a function of the unknown O2 exposure concentration, depending on the source of the leak and the salt composition. Evidence of this oxychloride claim and its subsequent decomposition is justified in this work.

20.
J Pain Symptom Manage ; 66(4): 351-360.e1, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37433418

RESUMO

CONTEXT: Emotion regulation by the physician can influence the effectiveness of serious illness conversations. The feasibility of multimodal assessment of emotion regulation during these conversations is unknown. OBJECTIVES: To develop and assess an experimental framework for evaluating physician emotion regulation during serious illness conversations. METHODS: We developed and then assessed a multimodal assessment framework for physician emotion regulation using a cross-sectional, pilot study on physicians trained in the Serious Illness Conversation Guide (SICG) in a simulated, telehealth encounter. Development of the assessment framework included a literature review and subject matter expert consultations. Our predefined feasibility endpoints included: an enrollment rate of ≥60% of approached physicians, >90% completion rate of survey items, and <20% missing data from wearable heart rate sensors. To describe physician emotion regulation, we performed a thematic analysis of the conversation, its documentation, and physician interviews. RESULTS: Out of 12 physicians approached, 11 (92%) SICG-trained physicians enrolled in the study: five medical oncology and six palliative care physicians. All 11 completed the survey (100% completion rate). Two sensors (chest band, wrist sensor) had <20% missing data during study tasks. The forearm sensor had >20% missing data. The thematic analysis found that physicians': 1) overarching goal was to move beyond prognosis to reasonable hope; 2) tactically focused on establishing a trusting, supportive relationship; and 3) possessed incomplete awareness of their emotion regulation strategies. CONCLUSION: Our novel, multimodal assessment of physician emotion regulation was feasible in a simulated SICG encounter. Physicians exhibited an incomplete understanding of their emotion regulation strategies.


Assuntos
Regulação Emocional , Médicos , Humanos , Relações Médico-Paciente , Estudos Transversais , Projetos Piloto , Médicos/psicologia , Comunicação
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