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The use of a centralized normothermic preservation and assessment center to rescue kidneys declined after standard allocation
No full textNormothermic machine perfusion (NMP) may increase utilization of non-ideal donor kidneys through improved preservation and assessment. We assessed the use of a centralized perfusion service to rescue declined kidneys for transplant. Kidneys that exhausted standard OPTN allocation underwent 2 hours of NMP for additional assessment. The primary outcome was rescue for transplantation. Outcomes of NMP kidneys were compared to non-NMP kidneys transplanted during the study period at the same transplant centers. NMP was performed on 104 declined kidneys, and 94 (90%) were rescued for transplant. NMP donors were older, with a higher kidney donor profile index (KDPI) compared to non-NMP donors. Cold ischemia time was significantly longer in the NMP cohort (median 37.6 vs. 22.1 hours, p<0.001). The weighted percentage of delayed graft function (DGF) was 26.3% in the NMP group vs 60.2% in the non-NMP group (p=0.023). Overall graft survival was similar between the groups. With the use of a centralized NMP service, kidneys declined based on standard clinical parameters may be evaluated, rescued, and successfully transplanted. Kidneys undergoing NMP experienced significantly lower rates of DGF compared to non-NMP kidneys. Additional follow up is needed to determine the effects of NMP on long-term graft function
Ketamine is Associated with Increased 24-Hour Mortality Following Traumatic Brain Injury Compared with Other Induction Medications, a Retrospective Study
No full textKetamine is a dissociative anesthetic often used for airway management in trauma. While perceived to preserve hemodynamic stability, concerns exist regarding its effects on intracranial pressure and cardiac output in critically ill patients. There is a lack of studies evaluating outcomes after ketamine administration in the setting of traumatic brain injury (TBI). This study aimed to investigate the effects of ketamine on outcomes and physiological responses in a large cohort of TBI patients. We hypothesized that ketamine administration would not be associated with differences in survival, vital signs, or disposition outcomes compared with other induction medications when administered following TBI. This was a retrospective, observational study utilizing data from the Linking Investigations in Trauma and Emergency Services registry (2017-2021). Subjects were divided into two groups: those who received only ketamine (n = 429) and those who received other induction medications (etomidate and/or propofol; n = 993). We compared 24-h mortality, initial in-hospital vital signs (systolic blood pressure [SBP], respiratory rate, heart rate, and Glasgow Coma Scale [GCS]), and hospital discharge disposition; a propensity score analysis adjusted for potential confounders including race, injury type, pre-hospital GCS, initial pre-hospital SBP and site location. Ketamine-exposed subjects were younger and presented with a worse clinical profile, including lower pre-hospital GCS (5 vs. 6, p < 0.01) and lower SBP (126.5 vs. 144.0 mmHg, p < 0.01) compared with the ketamine-unexposed group. Unadjusted analysis showed a significantly higher 24-h mortality rate in the ketamine-exposed group (3.5% vs. 1.4%, p = 0.02), as well as lower initial in-hospital vital signs. After propensity score adjustment, the odds of 24-h mortality remained significantly higher for the ketamine-exposed group (OR 2.358, p = 0.042). Hospital discharge disposition was not different between groups in any analysis. In this retrospective analysis, ketamine administration for pre-hospital airway management in TBI patients was associated with an increased 24-h mortality and lower in-hospital SBP, even after adjusting for baseline differences. However, injury severity and the length of time examined for mortality may explain the significant mortality association for ketamine in this study. Prospective studies are needed to examine the relationship between ketamine administration and mortality following TBI
Time to death and its determinants among cervical cancer patients in Tigray, Ethiopia: a retrospective follow up study
No full textCervical cancer remains one of the leading causes of cancer-related deaths among women in Ethiopia. However, limited evidence exists regarding the survival outcomes and associated factors among cervical cancer patients, particularly in conflict-affected regions like Tigray. This study aimed to assess the survival time and its predictors among cervical cancer patients treated at Ayder Comprehensive Specialized Hospital and Axum specialized referral hospitals between 2018 and 2023.
A retrospective follow-up study was conducted on 91 cervical cancer patients. Data were extracted from medical records using a structured checklist. The primary outcome was time to death from cervical cancer, measured in months. Survival probabilities were estimated using the Kaplan-Meier method, and the log-rank test was used to compare survival across categories. Life tables were used to summarize the probability of survival at specified time intervals. Cox proportional hazards model was employed to identify predictors of mortality, with hazard ratios and 95% confidence intervals reported. The Cox-Snell residual plot was used to assess model adequacy.
The overall median survival time was 19.5 months, with a Four-year cumulative survival rate of just 3.7%. The incidence rate was high at 40.5 per 1,000 person-months, based on a total follow-up time of 1,431 person-months. Survival outcomes were significantly worse than in comparable Ethiopian studies. Older age and those who underwent chemo and radiotherapy were significantly associated with increased hazard of death. Surprisingly, patients who reported that healthcare providers did not exhibit supportive and respectful behavior had a 62% lower hazard of death (HR = 0.38; 95% CI: 0.18-0.81), a counterintuitive finding that may reflect reverse causality or reporting bias.
Cervical cancer survival in this cohort was markedly low compared to national and international findings. Older age and chemotherapy were associated with higher mortality. The unexpected association between perceived provider behavior and survival warrants further qualitative investigation. To improve outcomes, targeted efforts should focus on strengthening early detection and treatment services, particularly for older women
Determination of Binary CO 2 /CH 4 Adsorption Isotherms and Kinetics over Hierarchical Activated Carbons via the Zero-Length Column Technique
No full textCurrent adsorption processes generally rely on unary adsorption isotherms to assess the efficacy of adsorbent materials suitable for a particular separation. While unary adsorption isotherms provide important information about the adsorbent’s affinities toward adsorbates of interest, they fail to accurately determine the real response of adsorbents in multicomponent systems. This is mainly due to cooperative and competitive adsorption phenomena that often take place in complex environments. As such, it is essential to obtain binary/multicomponent equilibrium data to have a realistic assessment of adsorption materials. In this work, we utilized the zero-length column (ZLC) technique to obtain binary adsorption isotherms of CO2 and CH4 over two hierarchical microporous-mesoporous carbons, namely, Br-318 and Nuchar. The ZLC generated low-pressure equilibrium isotherms of pure CO2 and CH4 closely resembled the volumetric isotherms, and the trend revealed by the experimental data of binary adsorption isotherms was qualitatively consistent with that obtained from the theoretical model, confirming the alignment between the two equilibrium data acquisition methods, as well as the theoretical and experimental approaches. The kinetic analysis of the ZLC profiles in the binary mixture indicated 55 and 66% reductions in diffusion of CO2 through Br-318 and Nuchar, respectively, in the presence of CH4 relative to the pure system. The findings of this investigation highlight the efficacy of the ZLC method in accurately determining the binary adsorption data
CryoEM structure of mGlu6 captures receptor activation prior to G protein coupling
No full textThe metabotropic glutamate receptor 6 (mGlu6) is essential for synaptic communication of rod photoreceptors, and mutations in mGlu6 lead to a blinding disorder. However, its structural organization remains unknown. Here, we present the structure of agonist-bound mGlu6, revealing an asymmetric dimer arrangement in the absence of a G protein. This indicates that agonist binding alone can induce the homodimeric receptor asymmetry in metabotropic glutamate receptors and structurally prime mGlu6 for activation by pre-organizing the transmembrane domain dimer interface for G protein binding. The structure also identifies noncanonical interactions between the cysteine-rich domain and extracellular loop 2, forming a unique interface that likely stabilizes the activation state. Mutational analyses of this interface reveal its role in maintaining rapid Gαo activation and surface targeting. The structure also permits mechanistic investigation of congenital stationary night blindness and reveals diverse effects of pathogenic mutations on surface trafficking, Gαo coupling, and activation dynamics, including unexpected gain-of-function. These results provide critical insight into the intermediate asymmetric structure of mGlu6 and offer a molecular framework for understanding the pathogenesis of inherited retinal disorders
Data associated with the publication: MPI-guided photothermal therapy of prostate cancer using stem cell delivery of magnetotheranostic nanoflowers
No full textThis dataset supports the study “MPI-Guided Photothermal Therapy of Prostate Cancer using Stem Cell Delivery of Magnetotheranostic Nanoflowers.” It centers on using human mesenchymal stem cells (hMSCs) to deliver gold–iron oxide nanoflowers (GIONFs) to prostate tumors and evaluating their intratumoral distribution, retention, and photothermal therapy efficacy. The dataset contains four components:
Histology – H&E staining of major organs (liver, kidney, spleen, lung) and tumor sections assessing biosafety, tissue morphology, and treatment response.
In vitro data – Characterization of GIONFs, cellular uptake studies, photothermal response measurements, and stem cell labeling assessments.
MPI data – Magnetic particle imaging tracking of GIONF-hMSC biodistribution, tumor retention, and whole-body localization over time.
PTT data – In vivo photothermal therapy studies evaluating temperature profiles, treatment efficacy, and long-term tumor recurrence following laser irradiation.
Together, these data describe the behavior of intracellularly delivered GIONFs, demonstrate the advantages of hMSC-mediated transport for enhanced tumor localization, and support the development of MPI-guided photothermal therapy for prostate cancer
Dissecting the Cellular and Molecular Mechanisms in Venous Remodeling and Arteriovenous Fistula Maturation
No full textAs of 2023, approximately 800,000 people suffer from End Stage Renal Disease (ESRD) in the United States, with nearly 70% relying on hemodialysis through a vascular access as their renal replacement therapy. The preferred way to establish vascular access is through an arteriovenous fistula (AVF), which are surgically created by anastomosing a vein to a nearby artery. When the vein is connected to the arterial circulation, it is exposed to supraphysiological flow rates (more than 20x the normal venous flow), wall shear stress, and an increased oxidative load. The venous adaptation to these conditions, known as venous remodeling, results in a thicker wall and larger luminal diameter. However, the molecular mechanisms behind this remarkable adaptation remain unclear. After surgical creation, the AVF has two possible outcomes; 1) AVF failure, defined by flow rates below 600mL/min, and a diameter of less than 6mm or 2) AVF maturation which means flow rates above 600mL/min, larger diameter and functioning as a suitable conduit for repeated vascular access. Unfortunately, 40-50% of all AVFs fail to become viable for hemodialysis without an intervention, exposing an already vulnerable patient population to additional surgical procedures and limiting their access to lifesaving hemodialysis sessions. AVF failure is associated with stenosis or narrowing of the venous lumen which is secondary to medial fibrosis of the vein and neointimal hyperplasia.</p
Signal Evolution and Island Diversification in a Caribbean Dwarf Gecko
No full textSpeciation may occur when animals diverge in communication traits that facilitate reproduction, such that animals with divergent signals can no longer recognize each other as mates or strongly prefer mates of their own species. These signals may be received via visual, auditory, or chemosensory means, and may be used in combination as multimodal communication. My dissertation focus is signal divergence and its influence on behavioral isolation. The Reef Gecko (Sphaerodactylus notatus) is a small lizard native to The Bahamas, Cuba, and Florida. Populations of this species have diverged in dichromatic pattern such that the Florida population is variably dichromatic while other populations are clearly dichromatic. To explore the complex biogeographical and evolutionary relationship between these subspecies, I use phylogenetic reconstruction, population genetics, and demographic modeling. I reconstructed evolutionary relationships and approximate time of divergence for these subspecies and used population structure analyses to identify patterns of co-ancestry within populations. By constructing demographic models based on geologic and climate change in the region, I tested for the effects of reproductive isolation and climate fluctuation on gene flow, building a more complete understanding of the history of this species. I then test the hypothesis that levels of sexual dichromatism facilitate sexual recognition in S. notatus. I recorded encounters between same sex and opposite sex pairs of geckos that were separated by a transparent barrier to prevent chemical communication. The Florida mainland population with variable sexual dichromatism was also tested without a transparent barrier, allowing comparison between encounters with and without use of chemical signal. Each encounter was evaluated for courtship or agonism between gecko pairs, allowing me to measure the influence of sexual dichromatism on the recognition of potential mates. In whole, my dissertation explores island diversification from a biogeographical, evolutionary, and behavioral perspective.</p
Associations Between Bilingualism, Executive Function, and Core Autism Traits
No full textAutism spectrum disorder (ASD) is associated with marked heterogeneity in executive function (EF) abilities. The concept of ‘bilingual advantage’ suggests individuals fluent in two languages develop cognitive advantages, particularly within the EF domain. Current research has produced mixed results with some studies reporting a bilingual advantage and others failing to replicate. Bilingualism in children with ASD is understudied, as clinical practitioners often advise against teaching two languages to these children. However, emerging studies suggest that bilingualism may ameliorate EF difficulties in children with ASD. Here, we examined the impact of bilingual exposure on parent-reported EF abilities of Inhibit, Shift and Emotional Control as well as core ASD traits of perspective taking, social communication, and repetitive behavior continuously in monolingual and bilingual children with and without ASD. Results suggest that bilingualism may work as a protective factor supporting inhibition, emotional control, and perspective taking skills in children with ASD. Notably, we also found indirect effects of bilingualism on perspective taking, social communication, and repetitive behaviors mediated by EF skills. These results are the first to our knowledge to demonstrate the cascading supportive influences bilingual experience can have on reducing ASD related symptoms.</p
Communicative Efforts in Workplace Microaggressions
No full textGiven the limited exploration of microaggression within the field of communication, this dissertation explores how communicative efforts can help to address workplace microaggressions. By employing a mixed-method approach, this dissertation investigates minoritized employees’ situational perceptions and coping strategies toward workplace microaggressions, and how organizations’ communication strategies, i.e., intervention messages, can enhance their problem awareness and active coping efforts. Study One conducted semi-structured in-depth interviews with female African American employees (N=8) and Asian American employees (N=11) to understand their lived experiences, situational perceptions, and coping efforts toward workplace microaggressions. Study Two conducted an online experiment with female African American employees (N=235) and Asian American employees (N=184) to examine the intervention message design on workplace microaggression. Theoretical implications for both communication discipline and microaggression literature, as well as practical implications for theory-based intervention programs for workplace microaggressions, are discussed. </p