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Carbazole derivatives, such as MeO-2PACz and 2PACz are known to improve the performance of halide perovskite solar cells by facilitating hole transfer. To assess their interaction with halide perovskites, we probed the hole transfer from excited CsPbBr3 quantum dots to MeO-2PACz and 2PACz using emission spectroscopic and transient absorption techniques. The different oxidation potentials of these two carbazoles result in divergent interactions with CsPbBr3 QDs. Whereas MeO-2PACz quenches the emission of CsPbBr3 QDs, 2PACz enhances the emission by remediating the surface traps. Transient absorption studies confirm the formation of MeO-2PACz+• cation radical with characteristic absorption in the near IR region. No such oxidation process was observed with 2PACz. The mechanistic insights into the interaction of the two carbazole derivatives with excited perovskite nanocrystals will add another piece to the untold story behind the improved performance of perovskite photovoltaic devices.
Skull base surgery is a highly innovative, multidisciplinary field that brings together teams of neurosurgeons, otolaryngology-head and neck surgeons (OHNS), plastic surgeons, ophthalmologists, radiation oncologists, and others. However, not long ago, the nascent field was instead characterized by isolated individual brilliance. This paper explores the contributions of several key players toward breaking silos and transforming the field into what it is today. Our analysis centers on the formation of the North American Skull Base Society (NASBS), and the instrumental role that it played in the development of skull base surgery. We interviewed 12 past presidents of the NASBS and 2 prominent figures in skull base surgery. The contents of those 20 hours and 38 minutes of interviews and documents from initial NASBS meetings were analyzed. Key moments were segmented into short video clips, which complement this manuscript and are available on the NASBS website. A compelling narrative of collaboration, mentorship, and tenacity emerged from our analysis. In the 20th century, the field of skull base surgery was characterized mainly by courageous but isolated efforts by neurosurgeons and OHNS surgeons. Through mentorship, collaboration, and incredible innovation, it has since grown into a multidisciplinary, cutting-edge specialty that utilizes the strengths of several medical specialties. This transformation was largely facilitated by the formation of the NASBS in 1989, which enabled worldwide communication and collaboration among those dedicated to advancing the field. The growth of skull base surgery in North America and the instrumental role of the NASBS highlight the power of collaboration and innovation. It is important to recognize and celebrate the key players who facilitated the creation and success of the NASBS, which continues to unite young members across countless disciplines under one banner.
Depression is highly prevalent among patients with lumbar degenerative disease and is associated with worse postoperative outcomes. However, a significant proportion of affected individuals remain undiagnosed. We aimed to evaluate the utility of PROMIS Depression scores in identifying patients with undiagnosed depression undergoing lumbar spine surgery and to characterize their clinical outcomes relative to patients with diagnosed and no depression. This retrospective cohort study included patients undergoing 1- or 2-level lumbar decompression or fusion between March 2019 and November 2021. Patients were stratified into three cohorts: diagnosed depression (PDD), no depression (NDD), and at-risk for undiagnosed depression (ARUD), defined as PROMIS Depression ≥55 without an ICD-10 diagnosis. Patient-reported outcomes were assessed preoperatively and at 6, 12, and 24 months postoperatively. Between group comparisons and baseline-adjusted ANCOVA models were performed, including subgroup analyses by procedure type (fusion vs. decompression) and revision status. Of 286 ICD-10-negative patients, 24.1% (n=69) met criteria for ARUD. Patient-reported outcome scores across all domains in the ARUD cohort mirrored those of the PDD group and were significantly worse than those of the NDD cohort at all timepoints (p<.001). PROMIS Depression showed a strong correlation with Anxiety (ρ>0.77) and moderate correlations with other domains. No significant difference was observed in outcomes between treated and untreated PDD patients. Older age was associated with reduced likelihood of diagnosis, while substance abuse history, pain clinic enrollment, and retired status predicted higher risk of undiagnosed depression. PROMIS Depression scores can identify patients with undiagnosed depression who experience similar impairments and postoperative outcomes as those with diagnosed depression. These findings support the routine use of PROMIS Depression as a screening tool to enhance preoperative psychiatric assessment in spine surgery patients.
Hermann J. Muller, Nobel Prize recipient for producing gene mutations, was the de facto leader of the radiation genetics community from the mid-1920s until he died in 1967. Muller had a major impact on US hereditary/cancer risk assessment policies/practices, and the course of the secondary school biological sciences curriculum development in the US and worldwide. Despite these accomplishments, Muller was at the center of provocative controversies. Within this context, this paper reports the discovery of a letter (April 4, 1956) from Muller to Warren Weaver, Chair of the BEAR I Genetics Panel, about a major controversy in which the radiation-induced hereditary damage estimates of Panelist Milisav Demerec were strikingly lower than those of others, especially Muller's. In this recently discovered letter, Muller attempted to reconcile these differences and unexpectedly claimed that Demerec's estimates were correct. However, Muller appears to have inexplicably confused the evaluation by switching his focus away from Demerec's data on radiation-induced mutation rates in bacteria to his old unresolved dispute with Demerec regarding fruit flies. He even suggested that Demerec was correct in that Muller's groundbreaking mutational research had induced mostly major chromosomal aberrations rather than gene mutations. Muller curiously suggested that he had thereby resolved the conflict amongst Demerec, himself, and other BEAR I Genetics Panel members. Yet, as noted, Demerec's data for the BEAR I Genetics Panel mutation risk estimates were based on his (i.e., Demerec's) more current research on bacteria, with Muller completely missing the entire point of the Panel's scientific conflict with the Demerec data. Thus, Muller never addressed the real issue. This transitory detachment from factual reality by Muller is obvious and acute. Finally, if Weaver had shared this letter from Muller with the BEAR I Genetics Panel, it seems possible that many members might have been so troubled by Muller's apparent detachment from reality (on such a consequential disagreement) that they would have questioned why they had allowed Muller to exert so much influence on their report.
Anthropogenic debris poses an increasing threat in the marine environment due to its persistence and adverse effects on marine biota and ecosystem services. Previous anthropogenic debris research has centred on shorelines, surface waters, the water column, coastal seafloor and deep-sea domain, leaving sea-caves largely overlooked. This study introduces a novel quantitative approach tailored for sea cave systems, broadening the scope of marine litter research beyond previously targeted environments. All surveyed sea caves contained debris, with densities ranging from 0.044 to 96.839 items m-2. Most debris was primarily transported via sea-based pathways, and consisted mainly of fragmented plastics (66 %). Occasionally debris was found embedded within tar layers, producing "plastitar" deposits on cave walls. Analyses revealed that wave exposure and available beach area influenced debris retention, while differences in cave architecture resulted in distinct interior spatial deposition patterns across two cave types, leading to the formation of accumulation hotspots. Findings demonstrate that semi-submerged sea caves serve as important reservoirs for anthropogenic marine debris alongside toxic chemical components and potentially associated harmful microbiomes. Such contamination poses risks to sea cave biota and likely compromises the conservation efforts for the Mediterranean monk seal (Monachus monachus).
This reflective essay tells of the dramatic story of the discovery of nonconvulsive status epilepticus in a previously-healthy 11 year old girl who presented to our children's hospital with confusion and personality changes. The piece also attempts to capture the striking divide between the emotion present in the room when she was given medications to abort the seizures and returned to normal and the sterile description of the encounter that lives on in the electronic medical record.
Years before his breakthrough on the genetic code and sharing the 1968 Nobel Prize in Physiology or Medicine, followed by important contributions in neurobiology, as a PhD student Marshall Nirenberg was the first to define cellular hexose transport, a discovery that has not been adequately recognized.
The path to the development of enoxaparin (Lovenox/Clexane), one of the most widely used low-molecular-weight heparins worldwide, was far from smooth. This narrative review, presented from the personal perspective of the senior author who lived this journey, describes the pivotal research conducted at McMaster University in Canada that transformed enoxaparin from a promising laboratory compound into a cornerstone of prevention and treatment of thrombosis. The story begins in the late 1970s with the observation that low-molecular-weight heparin, produced through controlled depolymerization, exhibited antithrombotic efficacy comparable with unfractionated heparin, with a reduced risk of bleeding in animal models. It concludes in the 1990s with the successful evaluation in clinical trials and the regulatory approval of enoxaparin for the prevention of deep vein thrombosis after orthopedic surgery.
Staphylococcus aureus is a formidable pathogen and major challenge to human health. However, the bacterium is dichotomous and also acts as an asymptomatic coloniser. Given its ubiquity, every individual has been exposed to the bacterium, which may 'tune' the host immune system. This prior exposure potentially hampers the efficacy of anti-S. aureus vaccines, diminishing their protective effect. Conversely, by preserving its niche as a commensal coloniser, the bacterium simultaneously contributes to host defence through interbacterial competition and stimulation of host immune responses, potentially fending off pathogenic threats. This review examines how S. aureus shapes host immunity via infection and colonisation and explores how S. aureus-associated immune tuning can be both problematic and beneficial for the host.
This study aims to investigate the relationship between AI dependence and nomophobia among medical students based on various demographic characteristics. This study adopts a quantitative correlational research design. Dependence on Artificial Intelligence Scale (DAI) and the Nomophobia Questionnaire (NMP-Q) were used to collect data. Data were collected online via Google Forms. Medical students from four public and two private universities in Turkey participated in the study. Data were analyzed using Pearson correlation analysis, Two-Way ANOVA, and Multiple Regression Analysis. The results revealed a significant positive correlation between AI dependence and nomophobia among medical students. Students who reported higher levels of AI dependence were also more likely to exhibit signs of smartphone addiction and internet access dependency. Demographic factors, such as gender, age and year of study, were found to have significant effects on the relationship. The study highlights a significant relationship between AI dependence and nomophobia among medical students, suggesting that overreliance on AI technologies may contribute to several negative consequences. The online version contains supplementary material available at 10.1186/s12909-026-08675-0.
Only 43 patients with laryngeal melanosis have been reported to date. Concomitant malignancy and dysplasia of the upper aerodigestive tract, ranging from 26% to 50%, have been encountered with this condition. Given the above, we undertook this study to assess the burden of laryngeal melanosis diagnosed in a tertiary care center. This was a retrospective observational study done with a review of all patients with laryngeal biopsies received over the previous 5-year period (2017-2022), on encountering an index patient. A representative slide from each patient was stained with Masson Fontana and bleached with potassium permanganate, and immunohistochemistry was performed using S100 and HMB45 (PMEL), wherever feasible. Sixty-five patients with laryngeal biopsies reported were included in the study, and laryngeal melanosis was detected in 9 patients (14% prevalence) of the total laryngeal biopsies. Seven out of 9 patients were associated with neoplasm, 6 patients (67%) with concomitant squamous cell carcinoma, and 1 (11%) with moderate dysplasia. We add another 9 patients to the list of laryngeal melanosis, based on our extensive literature search, taking the total to 52. We observed instances where laryngeal melanosis co-occurred with malignancies of the upper aerodigestive tract. Identifying laryngeal melanosis during direct laryngoscopy can serve as a marker that encourages surgeons and pathologists to exercise prudence and ensure thorough investigation.
Background: Black and racialized immigrants with disabilities in Canada face overlapping systems of exclusion rooted in racism, ableism, and migration status. Yet, their experiences within health and rehabilitation services during the COVID-19 pandemic remain largely undocumented. This study explores how structural inequities shaped access to healthcare, rehabilitation, information, and community supports in the Greater Toronto and Hamilton Area (GTHA). Methods: Using narrative inquiry, ten in-depth interviews were conducted with participants who identified as Black or racialized, disabled, and having immigrated to Canada within the last 10 years. Narratives were analyzed through reflexive thematic analysis to identify how systems, relationships, and policies interacted to shape daily life, health and rehabilitation navigation during the pandemic. Results: Participants described systemic barriers in health and rehabilitation systems, experiences of "othering" and conditional belonging, and the critical role of informal and faith-based networks in navigating inaccessible services. Pandemic policies often intensified existing inequities. Conclusions: Findings underscore the need for intersectional health and rehabilitation planning that centers the voices of Black and racialized disabled immigrants. Addressing systemic racism and ableism is essential for equitable preparedness in future public health emergencies.
Congenital anomalies are structural abnormalities that occur during intrauterine life and are prenatally or postnatally identifiable. They are major contributors to neonatal and under-5 mortality. Childbirth is a pleasant phase of life for parents who birth healthy newborns. However, this would mean something different for parents who give birth to children with congenital anomalies. Even though these anomalies can be treated surgically, parents experience physical, psychological, and economic difficulties. Most of the literature on parental experiences originates from high-income countries, making their context less applicable to low and middle-income countries (LMICs) such as Ethiopia. This study aimed to explore the firsthand experiences of Ethiopian parents raising children with congenital anomalies. A phenomenological study was conducted to explore the lived experiences of parents of children with congenital anomalies at two tertiary hospitals in South Ethiopia. Eighteen parents were purposively selected for the in-depth interviews. The interviews were audio recorded, transcribed, and translated. The rigor of the study was ensured by establishing its credibility, transferability, dependability, and conformability. Thematic analysis was performed using Open Code v4.03. Five overarching themes emerged. The themes include 'prior awareness, perception and discovery', 'parental emotional reaction', 'burden', 'support system', and 'impact of the anomaly'. Parents of children with congenital anomalies face challenges in obtaining healthcare services and experience financial and hygiene-related burdens because of their children's condition. They experience emotional distress and social difficulties, while relying on their limited community and familial support.
Patient and family perspectives on CDH are infrequently explored, impairing clinicians' understanding of illness impact on functioning and desired support. We investigated the lived experiences of CDH patients and primary caregivers, including those with neurodevelopmental impairment (NDI), regarding the adequacy of clinical and community support. Cross-sectional qualitative study convening focus groups (FGs) to explore CDH patient experiences within our CDH follow-up clinic. Participants >4 years were recruited between December 2023-March 2024. FGs were grouped by language preference, presence of NDI, and clinic graduate status. Virtual FG sessions were assessed using inductive thematic analyses. Twenty-six participants (10 CDH children/12 caregivers/4 clinic graduates) participated among 4 FGs. Thematic analysis revealed 4 themes: experiencing CDH as a caregiver; experiencing CDH as a child; striving for normalcy; and getting the support we need. Caregivers reported shock at CDH diagnosis and during initial hospitalization. Caregiver isolation/distress were common, particularly when physically separated from their newborn. Memories faded with time with parents revealing few long-term effects on their children. While most reported minimal impact, some CDH patients struggled with visible CDH indicators (e.g. scars). Patients expressed a high quality of life despite NDI or co-morbidities. Caregivers were satisfied with clinical support and easy contact but desired interaction with other CDH families for emotional/psychological support. This first study on CDH lived experiences revealed high quality of life, despite early challenges. Caregivers valued the CDH clinic for easy access to expert care but desired contact with other CDH families for emotional support. Level II (prospectively collected data, retrospective analysis).
In this second part of my editorial on the untold/hidden history of Western medicine, I look at the many efforts of the past 2 centuries to balance disease medicine with health medicine. Many brave and visionary men and women founded and promoted health medicine movements, but few were successful. I present here an overview of the key movements, why most failed, and what changed to allow health medicine (by whatever name) to finally endure.
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Docosahexaenoic acid (DHA), the dominant polyunsaturated fatty acid in photoreceptors, neurons, and synapses, is usually described as a passive structural membrane constituent. We propose a different view: DHA is a quantum-electronically active molecule whose methylene interrupted double-bond system creates an electron-rich matrix that couples with proteins to form quantum "clouds" and high-speed signaling central to recognition, recall, and cognition. Integrating evidence from molecular evolution, biophysics, and neuroscience, we argue that, as the original chromophore, DHA's unique properties enabled the emergence of the nervous system and continue to provide the electronic substrate for cognition. By suggesting that cognition depends not only on protein-based mechanisms but on DHA-mediated electron dynamics at the membrane-protein interface, this perspective reframes DHA as an active, conserved determinant of brain evolution and function.
Background and Objectives: Intravesical Bacillus Calmette-Guérin (BCG) therapy remains a cornerstone in the treatment of non-muscle-invasive bladder carcinoma due to its efficacy in reducing recurrence and progression rates. However, its use is associated with various complications-including urinary tract infections (UTIs)-which necessitates further exploration. This study aims to analyze UTIs occurring during intravesical BCG treatment, emphasizing the microbial spectrum, resistance patterns, and risk factors from an infectious diseases and clinical microbiology perspective. Materials and Methods: A retrospective analysis was conducted on 240 patients diagnosed with non-muscle-invasive bladder carcinoma who received intravesical BCG therapy between 2010 and 2021. Data were collected from hospital records, including demographic characteristics, comorbidities, number of intravesical BCG cycles, and microbiological findings. UTIs were classified based on susceptibility patterns, and statistical analyses were performed to determine associations between clinical variables and UTI risk. Results: UTIs developed in 39.1% (n = 94) of patients, with 25.8% (n = 62) caused by susceptible pathogens and 13.3% (n = 32) by resistant pathogens. The most common causative agent was Escherichia coli (80.7% in susceptible UTIs, 43.8% in resistant UTIs), followed by Pseudomonas aeruginosa and Klebsiella pneumoniae. The presence of diabetes mellitus and chronic kidney disease significantly increased the risk of developing a UTI (p < 0.05). A higher number of intravesical BCG cycles correlated with increased UTI occurrence (p < 0.001). Serum C-reactive protein (CRP) levels were significantly elevated in patients with resistant UTIs, while procalcitonin levels were not a reliable predictor of UTI occurrence. Conclusions: Intravesical BCG therapy is associated with a significant incidence of UTIs, particularly among patients with predisposing comorbidities. The increasing prevalence of antibiotic-resistant infections underscores the need for careful monitoring and targeted antimicrobial stewardship strategies. CRP may serve as a useful adjunctive marker for UTI diagnosis in this setting. Future studies should focus on optimizing infection control measures and refining diagnostic criteria to differentiate between BCG-related inflammation and infectious complications.