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IntroductionThe analysis of surgical research using bibliometric measures has become increasingly prevalent. Absolute citation counts (CC) or indices are commonly used markers of research quality but may not adequately capture the most impactful research. A novel scoring system, the disruptive score (DS) has been found to identity academic work that either changes paradigms (disruptive (DIS) work) or entrenches ideas (developmental (DEV) work). We sought to analyze the most DIS and DEV versus most cited research in civilian trauma.MethodsThe top papers by DS and by CC from trauma and surgery journals were identified via a professional literature search. The identified publications were then linked to the National Institutes of Health iCite tool to quantify total CC and related metrics. The top 100 DIS and DEV publications by DS were analyzed based on the area of focus, citation, and perceived clinical impact, and compared with the top 100 papers by CC.Results32 293 articles published between 1954 and 2014 were identified. The most common publication location of selected articles was published in Journal of Trauma (31%). Retrospective reviews (73%) were common in DIS (73%) and top CC (67%) papers, while DEV papers were frequently case reports (49%). Only 1 publication was identified in the top 100 DIS and top 100 CC lists. There was no significant correlation between CC and DS among the top 100 DIS papers (r=0.02; p=0.85), and only a weak correlation between CC and DS score (r=0.21; p

Oriented cell divisions balance self-renewal and differentiation in stratified epithelia such as the skin epidermis. During peak epidermal stratification, the distribution of division angles among basal keratinocyte progenitors is bimodal, with planar and perpendicular divisions driving symmetric and asymmetric daughter cell fates, respectively. An apically restricted, evolutionarily conserved spindle orientation complex that includes the scaffolding protein LGN/Pins/Gpsm2 plays a central role in promoting perpendicular divisions and stratification, but why only a subset of cell polarize LGN is not known. Here, we demonstrate that the LGN paralog, AGS3/Gpsm1, is a novel negative regulator of LGN and inhibits perpendicular divisions. Static and ex vivo live imaging reveal that AGS3 overexpression displaces LGN from the apical cortex and increases planar orientations, while AGS3 loss prolongs cortical LGN localization and leads to a perpendicular orientation bias. Genetic epistasis experiments in double mutants confirm that AGS3 operates through LGN. Finally, clonal lineage tracing shows that LGN and AGS3 promote asymmetric and symmetric fates, respectively, while also influencing differentiation through delamination. Collectively, these studies shed new light on how spindle orientation influences epidermal stratification.

ObjectiveTo understand patient attitudes and preferences when faced with the uncertainty of pregnancy of unknown location (PUL).DesignQualitative, interview-based study.SettingUniversity Hosptial.PatientsPatients aged >18 years sampled from the emergency department and a subspecialty fertility practice of a university hospital system.InterventionsSix to 8 weeks after resolution of a PUL, with an ultimate clinical outcome of either an intrauterine pregnancy, spontaneous abortion, or ectopic pregnancy. Participants underwent either surgical, medical, or expectant management.Main outcome measuresThematic analysis of the virtual, semistructured interviews (45-60 minutes in length) conducted with participants to identify commonly expressed priorities was performed.ResultsInterviews were completed from October 2020 to March 2021 until thematic saturation was achieved (n = 15). Resolution diagnoses included intrauterine pregnancy (26.7%, n = 4), ectopic pregnancy (40.0%, (n = 6), and spontaneous abortion (33.3%, n = 5). Moreover, 66.7% (n = 10) of the patients presented to the emergency department, whereas 33.3% (n = 5) presented to a subspecialty fertility clinic. All had desired pregnancies. Thematic analyses revealed 4 related priorities around PUL management: health of pregnancy; health of self; future fertility; and diagnostic prediction and diagnostic certainty. The relative balance of these priorities was dynamic and evolved throughout the course of management with different outcomes. A second set of themes related to logistical preferences included mental health support, clarity of treatment and next steps, and continuity of care. Interrater reliability was validated with a pooled κ of >0.8. Limitations include that all participants had desired pregnancies, and the experiences of those who experienced different pregnancy outcomes may have been affected by recall bias.ConclusionsThese data demonstrate novel themes around related priorities in patients with desired pregnancies diagnosed with a PUL previously underappreciated by clinicians. The balance of these priorities evolved throughout management with increasing information and clarity. Continually reevaluating relevant patient priorities and preferences is essential to the comprehensive management of PUL.

BACKGROUND/OBJECTIVES: Choroidal thinning has been suggested in Lebers hereditary optic neuropathy (LHON). No study has been conducted of the choroid in relation to the retinal ganglion cell-inner plexiform layer (RGC-IPL). We sought to measure choroidal thickness in chronic LHON and to correlate thickness changes with the RGC-IPL. SUBJECTS/METHODS: Chronic LHON, 11778 mitochondrial DNA (mtDNA) mutation, patients (26 eyes; mean age: 35.1 ± 16.1 years) were prospectively recruited at Doheny Eye Center, University of California Los Angeles from March 2016 to July 2017. Age-matched healthy controls (27 eyes; mean age: 32.4 ± 11.1 years) were enroled for comparison. Swept-source optical coherence tomography (SS-OCT) imaging was performed in chronic LHON patients and compared with age-matched healthy controls. RESULTS: The macular choroid was significantly thinner in chronic LHON (250.5 ± 62.2 μm) compared with controls (313.9 ± 60.2 μm; p

The advent of cell culture-based methods for the establishment and expansion of human corneal endothelial cells (CEnC) has provided a source of transplantable corneal endothelium, with a significant potential to challenge the one donor-one recipient paradigm. However, concerns over cell identity remain, and a comprehensive characterization of the cultured CEnC across serial passages has not been performed. To this end, we compared two established CEnC culture methods by assessing the transcriptomic changes that occur during in vitro expansion. In confluent monolayers, low mitogenic culture conditions preserved corneal endothelial cell state identity better than culture in high mitogenic conditions. Expansion by continuous passaging induced replicative cell senescence. Transcriptomic analysis of the senescent phenotype identified a cell senescence signature distinct for CEnC. We identified activation of both classic and new cell signaling pathways that may be targeted to prevent senescence, a significant barrier to realizing the potential clinical utility of in vitro expansion.

BACKGROUND: Alzheimers disease (AD) pathology precedes symptoms and its detection can identify at-risk individuals who may benefit from early treatment. Since the retinal nerve fiber layer (RNFL) is depleted in established AD, we tested whether its thickness can predict whether cognitively healthy (CH) individuals have a normal or pathological cerebrospinal fluid (CSF) Aß42 (A) and tau (T) ratio. METHODS: As part of an ongoing longitudinal study, we enrolled CH individuals, excluding those with cognitive impairment and significant ocular pathology. We classified the CH group into two sub-groups, normal (CH-NAT, n = 16) or pathological (CH-PAT, n = 27), using a logistic regression model from the CSF AT ratio that identified >85% of patients with a clinically probable AD diagnosis. Spectral-domain optical coherence tomography (OCT) was acquired for RNFL, ganglion cell-inner plexiform layer (GC-IPL), and macular thickness. Group differences were tested using mixed model repeated measures and a classification model derived using multiple logistic regression. RESULTS: Mean age (± standard deviation) in the CH-PAT group (n = 27; 75.2 ± 8.4 years) was similar (p = 0.50) to the CH-NAT group (n = 16; 74.1 ± 7.9 years). Mean RNFL (standard error) was thinner in the CH-PAT group by 9.8 (2.7) μm; p < 0.001. RNFL thickness classified CH-NAT vs. CH-PAT with 87% sensitivity and 56.3% specificity. CONCLUSIONS: Our retinal data predict which individuals have CSF biomarkers of AD pathology before cognitive deficits are detectable with 87% sensitivity. Such results from easy-to-acquire, objective and non-invasive measurements of the RNFL merit further study of OCT technology to monitor or screen for early AD pathology.

[This corrects the article DOI: 10.1371/journal.pone.0232785.].

Robotic surgery was first introduced in the 1980s as a system to aid patients in the battlefield. Since then, robotic surgery has become an important minimally invasive tool and plays an important role in elective surgery among various surgical specialties. However, the role for robotic surgery in the emergent setting is not well established or studied. Robotic surgery has been shown to be advantageous to both patients and operating surgeons. Though limited, studies have found robotic surgery in the acute setting to be safe for patients. These studies found robotic surgery to have improved perioperative outcomes when compared to an open or laparoscopic approach. Additionally, the robotic platform is thought to be an effective tool to prevent conversion to open procedures in emergent settings. Although some studies demonstrate advantages to robotic acute surgery, others have shown increased complications with robotic acute surgery or no distinct advantage when comparing robotic to laparoscopic surgery. Additionally, some of the published papers supporting the use of robotic surgery in the emergent setting may have a degree of bias favoring the robotic platform. Robotic surgery is a mainstay in minimally invasive elective surgery and gaining popularity among patients and surgeons. There are pros and cons to the adaptation of the robotic platform in the acute care setting. Additional large population studies are indicated to determine the true role of the robotic platform in the emergent setting. [ABSTRACT FROM AUTHOR]

Background: Autologous peripheral blood stem cell transplantation (aPBSCT) is the standard of care for adults with relapsed lymphoma, yet recipients remain at risk of developing chronic health conditions (CHCs). It was hypothesized that body composition measurements of skeletal muscle and fat are associated with late‐onset CHCs and nonrelapse mortality after aPBSCT. Methods: Leveraging the Blood or Marrow Transplant Survivor Study, we examined association between pre‐aPBSCT body composition and new‐onset grade 3–5 CHCs among 187 adults with lymphoma treated with aPBSCT (2011–2014) surviving ≥2 years after aPBSCT. Using computed tomography scans at the L3 level, skeletal muscle mass (skeletal muscle area and skeletal muscle density [SMD]) and body fat (subcutaneous adipose tissue and visceral adipose tissue) were measured and quantified as sex‐specific z‐scores. Competing risk models were built to study the impact of body composition on incident grade 3 through 5 CHCs and nonrelapse mortality (NRM) adjusting for confounders. Results: The study cohort had a median age at aPBSCT of 57 years with 63% males, 77% non‐Hispanic Whites and 81% with non‐Hodgkin lymphoma. The 5‐year cumulative incidence of grade 3 through 5 CHCs was 47% (95% Confidence Interval, CI, 38%–56%). Each SD increase in SMD was associated with 30% reduced risk of grade 3 through 5 CHCs (95% CI, 0.50–0.96). The 10‐year cumulative incidence of NRM was 16% (95% CI, 10–22). No body composition measure was associated with NRM. Conclusions: The association between SMD and grade 3 through 5 CHCs following aPBSCT could inform development of prognostic models to identify adults with lymphoma at greatest risk of morbidity following aPBSCT. [ABSTRACT FROM AUTHOR]

In Alzheimer's disease, soluble Aβ oligomers are believed to play important roles in the disease pathogenesis, and their levels correlate with cognitive impairment. We have previously shown that Aβ oligomers can be categorized into multiple structural classes based on their reactivity with conformation-dependent antibodies. In this study, we analyzed the structures of Aβ40 oligomers belonging to two of these classes: fibrillar and prefibrillar oligomers. We found that fibrillar oligomers were similar in structure to fibrils but were less stable towards denaturation while prefibrillar oligomers were found to be partially disordered. These results are consistent with previously proposed structures for both oligomer classes while providing additional structural information.

Genetic analysis of familial forms of Alzheimer's disease (AD) causally links the proteolytic processing of the amyloid precursor protein (APP) and AD. However, the specific type of amyloid and mechanisms of amyloid pathogenesis remain unclear. We conducted a detailed analysis of intracellular amyloid with an aggregation specific conformation dependent monoclonal antibody, M78, raised against fibrillar Aß42. M78 immunoreactivity colocalizes with Aß and the carboxyl terminus of APP (APP-CTF) immunoreactivities in perinuclear compartments at intermediate times in 10month 3XTg-AD mice, indicating that this represents misfolded and aggregated protein rather than normally folded APP. At 12months, M78 immunoreactivity also accumulates in the nucleus. Neuritic plaques at 12months display the same spatial organization of centrally colocalized M78, diffuse chromatin and neuronal nuclear NeuN staining surrounded by peripheral M78 and APP-CTF immunoreactivity as observed in neurons, indicating that neuritic plaques arise from degenerating neurons with intracellular amyloid immunoreactivity. The same staining pattern was observed in neuritic plaques in human AD brains, showing elevated intracellular M78 immunoreactivity at intermediate stages of amyloid pathology (Braak A and B) compared to no amyloid pathology and late stage amyloid pathology (Braak 0 and C, respectively). These results indicate that intraneuronal protein aggregation and amyloid accumulation is an early event in AD and that neuritic plaques are initiated by the degeneration and death of neurons by a mechanism that may be related to the formation of extracellular traps by neutrophils.

Background: Having been influenced by the trend of internationalization of higher education, most universities in Taiwan have implemented an English benchmark requirement for graduation, which requires students to demonstrate their English ability at a specified Common European Framework of Reference for Languages (CEFR) level through taking a standardized English language test (e.g., GEPT, IELTS, TOEFL iBT). This practice has been increasingly criticized for failing to achieve its intended goals of enhancing students' English language proficiency and increasing students' career mobility. Therefore, there is an urgent need to explore the consequences of using standardized tests in support of the policy. Methods: To this end, this study investigated students' views of the graduation policy in three universities where students are required to take the General English Proficiency Test (GEPT) prior to graduation. Structural equation modeling was employed to find the best fitting model that illustrates the complex interrelationships among test performance, students' perceptions of the requirement, test value, test anxiety, and learning motivation. Results: The findings show that university students, regardless of English proficiency, generally hold a positive attitude towards the English graduation benchmark policy. Results further reveal that the Intermediate group shows more positive attitudes towards the graduation requirement than the High-Intermediate group. SEM results show that the attitudes of university students towards the English graduation requirement positively impact their perceived test value and their learning motivation. However, there is no significant relationship between the attitudes towards the policy and test performance. Conclusions: The findings contribute to our understanding of university students as the major stakeholders who defined the context of test use.

Abstract Background It is well established that vaccination of humans and transgenic animals against fibrillar Aβ prevents amyloid accumulation in plaques and preserves cognitive function in transgenic mouse models. However, autoimmune side effects have halted the development of vaccines based on full length human Aβ. Further development of an effective vaccine depends on overcoming these side effects while maintaining an effective immune response. Results We have previously reported that the immune response to amyloid oligomers is largely directed against generic epitopes that are common to amyloid oligomers of many different proteins and independent of a specific amino acid sequence. Here we have examined whether we can exploit this generic immune response to develop a vaccine that targets amyloid oligomers using a non-human random sequence amyloid oligomer. In order to study the effect of vaccination against generic oligomer epitopes, a random sequence oligomer (3A) was selected as it forms oligomers that react with the oligomer specific A11 antibody. Oligomer mimics from 3A peptide, Aβ, islet amyloid polypeptide (IAPP), and Aβ fibrils were used to vaccinate Tg2576 mice, which develop a progressive accumulation of plaques and cognitive impairment. Vaccination with the 3A random sequence antigen was just as effective as vaccination with the other antigens in improving cognitive function and reducing total plaque load (Aβ burden) in the Tg2576 mouse brains, but was associated with a much lower incidence of micro hemorrhage than Aβ antigens. Conclusion These results shows that the amyloid Aβ sequence is not necessary to produce a protective immune response that specifically targets generic amyloid oligomers. Using a non-human, random sequence antigen may facilitate the development of a vaccine that avoids autoimmune side effects.

The impact of synthetic amyloid β (1–42) (Aβ1–42) oligomers on biophysical properties of voltage-gated potassium channels Kv 1.3 and lipid bilayer membranes (BLMs) was quantified for protocols using hexafluoroisopropanol (HFIP) or sodium hydroxide (NaOH) as solvents prior to initiating the oligomer formation. Regardless of the solvent used Aβ1–42 samples contained oligomers that reacted with the conformation-specific antibodies A11 and OC and had similar size distributions as determined by dynamic light scattering. Patch-clamp recordings of the potassium currents showed that synthetic Aβ1–42 oligomers accelerate the activation and inactivation kinetics of Kv 1.3 current with no significant effect on current amplitude. In contrast to oligomeric samples, freshly prepared, presumably monomeric, Aβ1–42 solutions had no effect on Kv 1.3 channel properties. Aβ1–42 oligomers had no effect on the steady-state current (at −80 mV) recorded from Kv 1.3-expressing cells but increased the conductance of artificial BLMs in a dose-dependent fashion. Formation of amyloid channels, however, was not observed due to conditions of the experiments. To exclude the effects of HFIP (used to dissolve lyophilized Aβ1–42 peptide), and trifluoroacetic acid (TFA) (used during Aβ1–42 synthesis), we determined concentrations of these fluorinated compounds in the stock Aβ1–42 solutions by 19F NMR. After extensive evaporation, the concentration of HFIP in the 100× stock Aβ1–42 solutions was ∼1.7 μM. The concentration of residual TFA in the 70× stock Aβ1–42 solutions was ∼20 μM. Even at the stock concentrations neither HFIP nor TFA alone had any effect on potassium currents or BLMs. The Aβ1–42 oligomers prepared with HFIP as solvent, however, were more potent in the electrophysiological tests, suggesting that fluorinated compounds, such as HFIP or structurally-related inhalational anesthetics, may affect Aβ1–42 aggregation and potentially enhance ability of oligomers to modulate voltage-gated ion channels and biological membrane properties.

Abstract Background Age-related neurodegenerative diseases share a number of important pathological features, such as accumulation of misfolded proteins as amyloid oligomers and fibrils. Recent evidence suggests that soluble amyloid oligomers and not the insoluble amyloid fibrils may represent the primary pathological species of protein aggregates. Results We have produced several monoclonal antibodies that specifically recognize prefibrillar oligomers and do not recognize amyloid fibrils, monomer or natively folded proteins. Like the polyclonal antisera, the individual monoclonals recognize generic epitopes that do not depend on a specific linear amino acid sequence, but they display distinct preferences for different subsets of prefibrillar oligomers. Immunological analysis of a number of different prefibrillar Aβ oligomer preparations show that structural polymorphisms exist in Aβ prefibrillar oligomers that can be distinguished on the basis of their reactivity with monoclonal antibodies. Western blot analysis demonstrates that the conformers defined by the monoclonal antibodies have distinct size distributions, indicating that oligomer structure varies with size. The different conformational types of Aβ prefibrillar oligomers can serve as they serve as templates for monomer addition, indicating that they seed the conversion of Aβ monomer into more prefibrillar oligomers of the same type. Conclusions These results indicate that distinct structural variants or conformers of prefibrillar Aβ oligomers exist that are capable of seeding their own replication. These conformers may be analogous to different strains of prions.

Background: Amyloid-related degenerative diseases are associated with the accumulation of misfolded proteins as amyloid fibrils in tissue. In Alzheimer disease (AD), amyloid accumulates in several distinct types of insoluble plaque deposits, intracellular A beta and as soluble oligomers and the relationships between these deposits and their pathological significance remains unclear. Conformation dependent antibodies have been reported that specifically recognize distinct assembly states of amyloids, including prefibrillar oligomers and fibrils. Results: We immunized rabbits with a morphologically homogeneous population of A beta 42 fibrils. The resulting immune serum (OC) specifically recognizes fibrils, but not random coil monomer or prefibrillar oligomers, indicating fibrils display a distinct conformation dependent epitope that is absent in prefibrillar oligomers. The fibril epitope is also displayed by fibrils of other types of amyloids, indicating that the epitope is a generic feature of the polypeptide backbone. The fibril specific antibody also recognizes 100,000 x G soluble fibrillar oligomers ranging in size from dimer to greater than 250 kDa on western blots. The fibrillar oligomers recognized by OC are immunologically distinct from prefibrillar oligomers recognized by A11, even though their sizes overlap broadly, indicating that size is not a reliable indicator of oligomer conformation. The immune response to prefibrillar oligomers and fibrils is not sequence specific and antisera of the same specificity are produced in response to immunization with islet amyloid polypeptide prefibrillar oligomer mimics and fibrils. The fibril specific antibodies stain all types of amyloid deposits in human AD brain. Diffuse amyloid deposits stain intensely with anti-fibril antibody although they are thioflavin S negative, suggesting that they are indeed fibrillar in conformation. OC also stains islet amyloid deposits in transgenic mouse models of type II diabetes, demonstrating its generic specificity for amyloid fibrils. Conclusion: Since the fibril specific antibodies are conformation dependent, sequence-independent, and recognize epitopes that are distinct from those present in prefibrillar oligomers, they may have broad utility for detecting and characterizing the accumulation of amyloid fibrils and fibrillar type oligomers in degenerative diseases.