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Androgen and glucocorticoid receptor activation is co-regulated via tissue-specific metabolism by 11[beta]-hydroxysteroid dehydrogenases
No full textDOTATATE Scan in Meningiomatosis in a Patient With Ophthalmoplegia
No full textDOTATATE (1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid [DOTA]‐octreotate) is a compound that binds somatostatin receptors seen in tumors such as meningiomas. Here, we present a case of a patient with progressive bilateral ophthalmoplegia due to meningiomatosis involving both cavernous sinuses, which was highlighted by DOTATATE imaging. Some studies have shown DOTATATE imaging is superior to contrast‐enhanced magnetic resonance imaging (MRI) in identifying extent of intraosseous meningioma growth, which has been associated with worse prognosis. DOTATATE imaging should be considered in cases of unknown diagnosis of mass lesions and lesions that are in areas not easily accessible to biopsy, such as the cavernous sinuses
Exchange of Dual Clumped Isotopes of CO2 With the Phosphoric Acid-Water System
No full textRationale The reaction of carbonate materials with phosphoric acid is a standard method for extracting CO2, not only for the subsequent analysis of the ratios of 13C/12C and 18O/16O but also for the ratios of 13C18O16O/12C16O16O and 12C18O18O/12C16O16O and the calculation of the Delta 47 and Delta 48 values. For the determination of Delta 47 and Delta 48 values, possible exchange between the CO2 and H2O in the acid is of particular importance as this influences the precision and accuracy of the measurement.Methods Stochastic and non-stochastic CO2 was exposed to "fresh" and "used" phosphoric acid at 90 degrees C. Fresh acid is defined as acid that had not previously reacted with calcium carbonate, whereas "used" acid had previously dissolved a significant amount of carbonate material. The delta 13C, delta 18O, Delta 47, and Delta 48 values of the CO2 were then measured using a Thermo-253 plus using conventional methods, and the rate and the amount of exchange were determined.Results When exposed to "fresh" phosphoric acid, 13C18O16O and 12C18O18O readily exchanged with the H2O in the acid, attaining Delta 47 and Delta 48 values close to those expected as a result of equilibration with H2O at 90 degrees C. In contrast with "used" acid, the rate of exchange of 13C18O16O with H2O in the acid was negligible, whereas the exchange of 12C18O18O, although reduced compared with "fresh" acid, was still significant.Conclusions Such data have implications on the precision and accuracy of Delta 47 and Delta 48 values in systems in which the acid has been previously used to react in multiple samples, as well as in those in which fresh acid is used for every sample. The use of a sacrificial amount of carbonate prior to the reaction of "real" samples will reduce some of the changes observed in this study
Amazonian Transmedia: Seeking Epistemic and Ecological Justice in the Anthropocene
No full textThis dissertation, "Amazonian Transmedia: Seeking Epistemic and Ecological Justice in the Anthropocene," examines the struggles for multispecies justice within the Amazon. The Amazon, the world’s largest rainforest, remains divided among nine nation-states, subjected to extractivist pressures, and is now home to 30 million people. This rainforest faces increasing threats from extrctive industries like mining, oil, and agribusiness, whose expanding extractive frontiers exacerbate ecological destruction and infringe upon Indigenous rights. Amid these pressures, Indigenous communities, environmental activists, and transnational networks resist neoextractive forces through transmedia storytelling, employing literature, film, social media, and legal activism to advocate for ecological and epistemic justice. This sutdy focuses on three case studies that illustrate the diversity of threats and responses within Amazonia: the Yanomami people's resistance to gold mining in Brazil, the global and Indigenous media response to the Amazon forest fires in 2019, and the Sarayaku community's fight to protect their territory in Ecuador from oil extraction. These cases highlight how Indigenous communities assert sovereignty, amplify traditional ecological knowledge, and build global alliances to challenge dominant narratives and mitigate climate change. This project positions Amazonia as a critical site of ecological importance and epistemic resistance, where Indigenous knowledges and experiences intersect with digital media to influence environmental governance and explore sustainable futures. By analyzing the use of digital platforms and transmedia strategies, the research contributes to cultural studies, environmental humanities, and decolonial theory, demonstrating the transformative potential of Indigenous-led media in advocating for justice and the wellbeing of the rainforest and its multispecies communities.</p
59 - Management of tumors of the anal region
No full textManagement of perianal tumors is constantly evolving as our understanding of these rare, heterogenous lesions matures. Whereas traditional treatment often consisted of radical surgical resection with high morbidity and significant impact on quality of life, nonoperative or minimally invasive approaches to treating these tumors have emerged with acceptable clinical outcomes. This chapter will review the epidemiology, diagnosis, and up-to-date management of the common tumors of the perianal region that surgeons may encounter in their practice
97 - Ovarian and Other Adnexal Masses in Pregnancy
No full textThis chapter offers a comprehensive look at the epidemiology of adnexal masses during pregnancy. It delves into the different categories of adnexal masses, examines the diagnostic characteristics distinguishing benign and malignant masses, and explores suitable management strategies for clinicians managing the intricacies of pregnancy. The overarching goal is to offer clarity while consistently assessing the risks and benefits to both mother and fetus to guide informed decision-making that prioritizes optimal maternal-fetal outcomes in clinical practice
MRI-based patient selection for active surveillance in prostate cancer using U-Found: a generalized deep learning model
No full textBackground Current MRI prostate cancer risk assessment methods focus mainly on detecting tumor lesions, ignoring the prostate gland macro-environment which may also impact disease progression. A generalized deep-learning model for prostate may help capture these gland-level characteristics through deep embeddings which can be used for a variety of downstream tasks. This study aims to assess whether U-Found, a generalized multiparametric (mp)MRI-based model, offers added value in predicting histopathological progression in active surveillance (AS) patients.The prostate macro-environment, captured in U-Found embeddings, is hypnotized to play a significant role in differentiating patients who progress to definitive treatment from those whose tumor is kept at bay. Methods U-Found was trained on a dataset comprising over 3000 mpMRIs from in-house and public sources using self-supervised learning. Axial slices were represented in a 128-dimentional space. The physical interpretation of the embeddings was explored by investigating images that are closest to the centroid of embeddings clusters. U-Found was tested on a downstream task: identifying cancer in an independent dataset (publicly available UCLA dataset, n = 1,151).To determine the added value of U-Found embeddings to clinical and intratumoral radiomics features, we compared models for predicting histopathological progression in 144 participants of a prospective AS trial. In addition, associations between U-Found embeddings and lesion-and prostate radiomics were investigated. Results Our findings suggest that U-Found captures key characteristics of the prostate gland's macro-environment. U-Found successfully detected cancer in an independent UCLA dataset without being explicitly trained for lesion detection (AUC= 0.79).The prediction model incorporating a combination of clinical variables, mpMRI-derived intratumoral radiomics features and deep embeddings generated by U-Found achieved AUC = 0.86, outperforming models solely based on clinical and/or radiomics features. There were clear associations between U-Found embeddings and radiomics features. Conclusions U-Found was designed as a generalized self-supervised foundation model for prostate imaging, enabling the model to learn intrinsic imaging structures. We demonstrate that U-Found embeddings capture key features of the prostate macro-environment, which appear to contribute to disease progression, albeit to a lesser extent than tumor-specific imaging features.</p
Awake craniotomy for brain tumor resection in the elderly: an institutional experience
No full textAwake craniotomy (AC) maximizes safe resection of tumors that encroach on functionally critical areas. However, AC presents additive challenges that are further compounded in the geriatric population. We aim to show that AC is safe and feasible in the elderly, and reveal which peri-operative metrics contribute towards post-operative outcomes, including length of stay, readmissions and discharge disposition.
We conducted a decade-long retrospective review of AC in patients older than 75 years old. Multivariate linear and logistic regressions were used to identify independent predictors of re-admission, length of stay in ICU and the hospital, and discharge disposition. Variables included Karnofsky Performance Status (KPS), American Society for Anesthesiologists score, frailty index (mFI-11), age in addition to other key metrics.
There were 70 patients with mean age 80 and KPS 75.2 included in our cohort. Glioblastoma was the most common pathology (61.4%) followed by metastasis (22.9%). Only one patient required conversion to general anesthesia, and there were three (4.3%) who had post-operative complications. Re-operation rates following neurosurgical re-admission were 11.4%. Patients with higher pre-operative KPS had shorter hospitalizations (ρ = -0.31, p = 0.011). Regarding readmission, mFI-11 was an independent predictor of all-cause 30-day readmission (OR 2.38, p = 0.007). In contrast, when restricting analysis to neurosurgery-specific readmissions, age emerged as the only inverse predictor (OR 0.59, p = 0.010).
AC is a feasible and necessary tool in the geriatric population. In appropriately organized centers, the surgical success of AC in the elderly can be high. Lower frailty (rather than younger age) predicted shorter stays and reduced all-cause re-admission rates
High-performance nanodevices based on WGe 2 N 4 monolayer
No full textTwo-dimensional (2D) MA2Z4-family monolayers (MLs) have emerged as promising semiconductors due to their element tunability and rich electronic and optoelectronic properties. In this work, using firstprinciples calculations, we investigate the electronic, mechanical, transport, and optoelectronic properties of WGe2N4 ML with a small indirect bandgap. Various nanodevices based on WGe2N4 ML are studied, including pn-junction diodes, pin-junction field-effect transistors (FETs), and phototransistors. The present results reveal that the WGe2N4 ML exhibits high rigidity, thermal stability, and remarkable light absorption. These nanodevices demonstrate excellent performance: (1) the pn-junction diode shows a high rectification ratio and a near-Shockley-limit ideality factor, (2) the pin-junction FET exhibits significant gate voltage modulation capability with subthreshold swing as low as 71 mV/dec (close to the theoretical limit calculated based on the Boltzmann distribution), and (3) the phototransistor displays strong optoelectronic responses in the visible and ultraviolet regions. These findings establish WGe2N4 ML as a versatile platform for developing high-performance, multifunctional nanoelectronic and optoelectronic devices, significantly expanding the application potential of MA2Z4-family materials.</p
VaginosCUPy: Using a Modified Menstrual Cup for Hands-Free Vaginoscopic Hysteroscopy. A feasibility trial
No full textTo evaluate the effectiveness and safety of using a modified menstrual cup for vaginal distention during vaginoscopic hysteroscopy and to assess patient’s discomfort and its impact on surgical ergonomics.
Prospective, single-arm feasibility study
Ambulatory minimally invasive gynecologic surgery units at a public teaching hospital and a private clinic in Caracas, Venezuela.
Sixty-three women aged 16–70 years undergoing diagnostic or operative vaginoscopic hysteroscopy between February 1st and November 30th, 2024.
A modified silicone menstrual cup (stem removed, central aperture created) positioned in the lower third of the vagina to facilitate distention and permit two-handed instrumentation of the hysteroscopic procedure (“VaginosCUPy” technique).
Successful cup insertion and adequate vaginal distention occurred in 59/63 (93.7%) of the cases. Four postmenopausal women with severe vaginal atrophy could not tolerate the insertion of the CUP. Among successful cases, optimal distention and full visualization were achieved in 59/59 (100%). Cervical stenosis was encountered in 20/63 (31.7%) of the cases; all were overcome and treated using micro-scissors, electrodes, or graspers without complications. Five adolescents with obstructive Müllerian anomalies underwent resection of transverse or oblique vaginal septa with satisfactory immediate results. Patient discomfort was low: 49/63 (77.8%) reported mild pain (VAS 2/10), 10/63 (15.9%) moderate (VAS 3/10), and 4/63 (6.3%) severe. Surgeons rated insertion “easy” in 51/63 (81.0%) and reported improved ergonomics in all successful procedures. No adverse events occurred.
Using a modified menstrual cup enables safe and reliable vaginal distension during vaginoscopic hysteroscopy, allowing for a hands-free approach that improves ergonomics and facilitates the hysteroscopic procedure. Further evaluation is warranted in postmenopausal and virginal patients