Miracle-dz/UniFAR-FTUs huggingface dataset:
Visualizing context-dependent calcium signaling in encephalitogenic T cells in vivo by two-photon microscopy

Significance Before invading the central nervous system, encephalitogenic T cells cross a series of microenvironments where they interact with local cells. T-cell activation was visualized by specific calcium signals using a combination of a genetic calcium reporter, Twitch1, and in vivo two-photon microscopy. In peripheral immune organs, short-lived calcium signaling indicated antigen-independent interactions. By contrast, in the CNS, saturated long-lived calcium signaling was induced by endogenous autoantigens presented by a subset of local antigen-presenting cells. Because T-cell trafficking is controlled at serial checkpoints, our findings may help to identify therapeutic targets for preventing CNS inflammation. In experimental autoimmune encephalitis (EAE), autoimmune T cells are activated in the periphery before they home to the CNS. On their way, the T cells pass through a series of different cellular milieus where they receive signals that instruct them to invade their target tissues. These signals involve interaction with the surrounding stroma cells, in the presence or absence of autoantigens. To portray the serial signaling events, we studied a T-cell–mediated model of EAE combining in vivo two-photon microscopy with two different activation reporters, the FRET-based calcium biosensor Twitch1 and fluorescent NFAT. In vitro activated T cells first settle in secondary (2°) lymphatic tissues (e.g., the spleen) where, in the absence of autoantigen, they establish transient contacts with stroma cells as indicated by sporadic short-lived calcium spikes. The T cells then exit the spleen for the CNS where they first roll and crawl along the luminal surface of leptomeningeal vessels without showing calcium activity. Having crossed the blood–brain barrier, the T cells scan the leptomeningeal space for autoantigen-presenting cells (APCs). Sustained contacts result in long-lasting calcium activity and NFAT translocation, a measure of full T-cell activation. This process is sensitive to anti-MHC class II antibodies. Importantly, the capacity to activate T cells is not a general property of all leptomeningeal phagocytes, but varies between individual APCs. Our results identify distinct checkpoints of T-cell activation, controlling the capacity of myelin-specific T cells to invade and attack the CNS. These processes may be valuable therapeutic targets.
Mouse model of Epstein–Barr virus LMP1- and LMP2A-driven germinal center B-cell lymphoproliferative disease

Significance Epstein–Barr virus (EBV) is a major cause of B-cell lymphomas in immunocompromised hosts, where viral oncoproteins cause malignancy with loss of immunosurveillance. The EBV membrane oncoproteins latent membrane protein 1 (LMP1) and LMP2A are coexpressed in EBV-associated immunosuppressed host and Hodgkin lymphomas, where they activate key B-cell growth and survival pathways. We established a transgenic mouse model of LMP1/2A coexpression in germinal center (GC) B cells, the cell type from which most EBV-driven lymphomas arise. Our model highlighted synergistic LMP1/2A effects on this important B-cell population. Upon suppression of T and natural killer cells, LMP1/2A caused B-cell differentiation into rapidly growing plasmablasts that were not observed with LMP1 or LMP2A alone. Our model highlights synergistic LMP1/2A GC B-cell effects and recapitulates key aspects of EBV-driven lymphoproliferative disease. Epstein–Barr virus (EBV) is a major cause of immunosuppression-related B-cell lymphomas and Hodgkin lymphoma (HL). In these malignancies, EBV latent membrane protein 1 (LMP1) and LMP2A provide infected B cells with surrogate CD40 and B-cell receptor growth and survival signals. To gain insights into their synergistic in vivo roles in germinal center (GC) B cells, from which most EBV-driven lymphomas arise, we generated a mouse model with conditional GC B-cell LMP1 and LMP2A coexpression. LMP1 and LMP2A had limited effects in immunocompetent mice. However, upon T- and NK-cell depletion, LMP1/2A caused massive plasmablast outgrowth, organ damage, and death. RNA-sequencing analyses identified EBV oncoprotein effects on GC B-cell target genes, including up-regulation of multiple proinflammatory chemokines and master regulators of plasma cell differentiation. LMP1/2A coexpression also up-regulated key HL markers, including CD30 and mixed hematopoietic lineage markers. Collectively, our results highlight synergistic EBV membrane oncoprotein effects on GC B cells and provide a model for studies of their roles in immunosuppression-related lymphoproliferative diseases.
Factors associated with smoking behaviour change in UK military personnel.

Background Research in the UK civilian population suggests that poor mental health outcomes are associated with smoking behaviour. In the UK military population, smoking cessation is associated with deployment in the reserve forces. However, little is known about the links between mental health outcomes and smoking initiation and cessation in the UK military. Aims The aim of this longitudinal study was to examine change in mental health and military factors associated with smoking initiation and cessation in a representative sample of UK military personnel. Methods Data were collected between 2003 and 2009; 5138 regular and reserve military personnel were included in the analyses. Results The results showed that smoking initiation was associated with symptoms of psychological distress, symptoms of probable post-traumatic stress disorder (PTSD), relationship breakdown and deployment. Conclusions These findings are consistent with existing research in civilian populations showing links between poor mental health and smoking behaviour. Furthermore, our finding that deployment is associated with smoking initiation is also in line with research from the US military and UK reserves.
H2O2-responsive liposomal nanoprobe for photoacoustic inflammation imaging and tumor theranostics via in vivo chromogenic assay

Significance Hydrogen peroxide is closely associated with many important physiological and pathological events. Herein, we develop a liposomal nanoprobe for in vivo H2O2-responsive chromogenic assay, which is highly specific and sensitive to H2O2. Using such a nanoprobe, photoacoustic imaging of H2O2-related inflammation processes in mice induced by either LPS or bacteria is realized. Meanwhile, such a nanoprobe, by reacting with endogenous H2O2 produced by tumor cells, allows sensitive photoacoustic imaging of early-stage small tumors and orthotopic brain glioma and even enables accurate differentiation of metastatic sentinel lymph nodes from nonmetastatic ones. Furthermore, owing to its H2O2-responsive near-infrared absorbance, selective photothermal ablation of tumors is also achieved, illustrating the promise of using this nanoproble for tumor theranostics with great specificity. Abnormal H2O2 levels are closely related to many diseases, including inflammation and cancers. Herein, we simultaneously load HRP and its substrate, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), into liposomal nanoparticles, obtaining a Lipo@HRP&ABTS optical nanoprobe for in vivo H2O2-responsive chromogenic assay with great specificity and sensitivity. In the presence of H2O2, colorless ABTS would be converted by HRP into the oxidized form with strong near-infrared (NIR) absorbance, enabling photoacoustic detection of H2O2 down to submicromolar concentrations. Using Lipo@HRP&ABTS as an H2O2-responsive nanoprobe, we could accurately detect the inflammation processes induced by LPS or bacterial infection in which H2O2 is generated. Meanwhile, upon systemic administration of this nanoprobe we realize in vivo photoacoustic imaging of small s.c. tumors (∼2 mm in size) as well as orthotopic brain gliomas, by detecting H2O2 produced by tumor cells. Interestingly, local injection of Lipo@HRP&ABTS further enables differentiation of metastatic lymph nodes from those nonmetastatic ones, based on their difference in H2O2 contents. Moreover, using the H2O2-dependent strong NIR absorbance of Lipo@HRP&ABTS, tumor-specific photothermal therapy is also achieved. This work thus develops a sensitive H2O2-responsive optical nanoprobe useful not only for in vivo detection of inflammation but also for tumor-specific theranostic applications.
Tabagismo e controle da asma brônquica

Limited control of asthma constitutes a serious health problem worldwide. Various factors, such as environmental changes and patient lifestyles, are likely responsible for the minimal success of attempts to control asthma. Consequently, asthma control is the central focus of the updated version of the Global Initiative for Asthma Guidelines, which encourage physicians to concentrate on evaluating the degree of asthma control, defined by the symptoms and pulmonary function, as well as by the presence or history of exacerbations. (1) Similarly, the smoking epidemic remains a public health concern worldwide, and exposure to tobacco smoke makes it even more difficult to control symptoms in patients with asthma. (2) In recent decades, we have observed major advances in the understanding of the physiopathology of asthma and great improvements in the medications used in its control. However, it is known that there is great individual variability in the treatment response, which involves genetic and environmental factors. In general, clinical trials of asthma treatments exclude smoking patients due to the risk of including patients with COPD. Therefore, little is known regarding the treatment response of this specific group of patients. (3) In Brazil, the difficulty in controlling asthma can be accentuated if we consider that most patients with asthma are not adequately monitored, evaluations often being performed by non-specialized physicians. This also takes place in developed countries. In a recent study evaluating more than 10,000 patients with asthma, it was reported that the disease was uncontrolled in 59% of the patients, well controlled in 19% and totally controlled in only 23% [sic]. In addition, the study indicated that poorly controlled asthma is more common among smoking patients than among nonsmoking patients. (4) There has been a significant decrease in the prevalence of smoking, especially in developed countries. This decrease is due to the implementation of appropriate policies for its control, which has not occurred in most developing Smoking and asthma control
Metallacycle-cored supramolecular assemblies with tunable fluorescence including white-light emission

Significance Light-emitting materials have been widely studied for their promising applications in chemical and biological science. Here we report three phenanthrene-21-crown-7 functionalized fluorescent Pt(II) rhomboidal metallacycles which were then converted into fluorescent supramolecular oligomers by reacting with a bis-ammonium linker. One of these constructs shows concentration-dependent fluorescence in a wide color range, where orange emission at high concentration and blue emission at low concentration was observed. Moreover, at a concentration of 29 µM the same ensemble emits white light that has emerged from the integration of the complementary orange and blue color from the metallacycles and linker, respectively. This study shows how light-emitting materials can be obtained by the proper implementation of multiple orthogonal interactions in a single process. Control over the fluorescence of supramolecular assemblies is crucial for the development of chemosensors and light-emitting materials. Consequently, the postsynthetic modification of supramolecular structures via host–guest interactions has emerged as an efficient strategy in recent years that allows the facile tuning of the photophysical properties without requiring a tedious chemical synthesis. Herein, we used a phenanthrene-21-crown-7 (P21C7)-based 60° diplatinum(II) acceptor 8 in the construction of three exohedral P21C7 functionalized rhomboidal metallacycles 1–3 which display orange, cyan, and green emission colors, respectively. Although these colors originate from the dipyridyl precursors 10–12, containing triphenylamine-, tetraphenylethene-, and pyrene-based fluorophores, respectively, the metal–ligand coordination strongly influences their emission properties. The metallacycles were further linked into emissive supramolecular oligomers by the addition of a fluorescent bis-ammonium linker 4 that forms complementary host–guest interactions with the pendant P21C7 units. Notably, the final ensemble derived from a 1:1 mixture of 1 and 4 displays a concentration-dependent emission. At low concentration, i.e., <25 µM, it emits a blue color, whereas an orange emission was observed when the concentration exceeds >5 mM. Moreover, white-light emission was observed from the same sample at a concentration of 29 µM, representing a pathway to construct supramolecular assemblies with tunable fluorescence properties.
Lipid rafts sense and direct electric field-induced migration

Significance Electric fields control embryonic development and wound healing through directing and enhancing cell migration and proliferation. However, details pertaining to electric sensing of cells remain unclear. Many studies have reported involvement of different cell surface proteins, yet the identity of the electric field sensor is unknown. We demonstrate that the detergent-resistant membrane nanodomains, known as lipid rafts, act as the primary sensor to electric field-induced directional cell migration. These nanodomains respond to electric fields as mobile complexes that polarize, coalesce, and partition membrane proteins and in turn activate intracellular signaling events to orient cell migration. Endogenous electric fields (EFs) are involved in developmental regulation and wound healing. Although the phenomenon is known for more than a century, it is not clear how cells perceive the external EF. Membrane proteins, responding to electrophoretic and electroosmotic forces, have long been proposed as the sensing molecules. However, specific charge modification of surface proteins did not change cell migration motility nor directionality in EFs. Moreover, symmetric alternating current (AC) EF directs cell migration in a frequency-dependent manner. Due to their charge and ability to coalesce, glycolipids are therefore the likely primary EF sensor driving polarization of membrane proteins and intracellular signaling. We demonstrate that detergent-resistant membrane nanodomains, also known as lipid rafts, are the primary response element in EF sensing. The clustering and activation of caveolin and signaling proteins further stabilize raft structure and feed-forward downstream signaling events, such as rho and PI3K activation. Theoretical modeling supports the experimental results and predicts AC frequency-dependent cell and raft migration. Our results establish a fundamental mechanism for cell electrosensing and provide a role in lipid raft mechanotransduction.
Biodegradable Electronic Systems in 3D, Heterogeneously Integrated Formats

Biodegradable electronic systems represent an emerging class of technology with unique application possibilities, from temporary biomedical implants to “green” consumer gadgets. This paper introduces materials and processing methods for 3D, heterogeneously integrated devices of this type, with various functional examples in sophisticated forms of silicon‐based electronics. Specifically, techniques for performing multilayer assembly by transfer printing and for fabricating layer‐to‐layer vias and interconnects by lithographic procedures serve as routes to biodegradable, 3D integrated circuits composed of functional building blocks formed using specialized approaches or sourced from commercial semiconductor foundries. Demonstration examples range from logic gates and analog circuits that undergo functional transformation by transience to systems that integrate multilayer resistive sensors for in situ, continuous electrical monitoring of the processes of transience. The results significantly expand the scope of engineering options for biodegradable electronics and other types of transient microsystem technologies.
Time-of-Transfer and the Outcomes of Attending a Four-Year College: Evidence from SUNY

This paper examines the relationships between time of transfer from community college to four-year college and three outcomes of attending four-year college: probability of baccalaureate, time to baccalaureate, and credits earned at baccalaureate. Using enrollment data from the State University of New York, I establish that transfer students from community colleges have a longer and more widespread time-to-baccalaureate distribution than do non-transfer (“native”) students, are more likely to have taken time off than natives with the same number of terms completed, and also have fewer credits accumulated than equivalent natives. Multinomial Logit estimations show that “transferring up” after the first, second, and fourth semester of community college attendance is associated with the highest probability of eventual baccalaureate receipt. However, when I add controls for time taken off and credits accumulated, there is a “U-shaped” impact of time spent at a two-year college on the probability of earning a baccalaureate within eight years, with transferring after five semesters now yielding the lowest likelihood of 8-year baccalaureate. Those who transfer “early”—having completed fewer than four community college terms—and do not quickly attrite do not maintain the credit and enrollment statuses of equivalent natives; those who transfer “late”—after six or more semesters at community college—typically earn more credits in a semester than equivalent natives. Without controlling for pre-transfer attendance factors, transferring after four semesters appears to yield the shortest time-to-baccalaureate for those who eventually graduate; when controls for demographics and credits accumulated are added, transferring after exactly one semester yields a significantly higher time-tobaccalaureate for engineering and biological science majors. Transferring up after four or more semesters is associated with extra credits at baccalaureate receipt for students in both math/science majors and majors in large occupational fields, though the impacts are not particularly large in important fields of study.
Efficacy of Endoscopic Fluorescein Video Angiography in Aneurysm Surgery-Novel and Innovative Assessment of Vascular Blood Flow in the Dead Angles of the Microscope.

BACKGROUND In aneurysm surgery, assessment of the blood flow around the aneurysm is crucial. Recently, intraoperative fluorescence video angiography has been widely adopted for this purpose. However, the observation field of this procedure is limited to the microscopic view, and it is difficult to visualize blood flow obscured by the skull base anatomy, parent arteries, and aneurysm. OBJECTIVE To demonstrate the efficacy of a new small-caliber endoscopic fluorescence video angiography system employing sodium fluorescein in aneurysm surgery for the first time. METHODS Eighteen patients with 18 cerebral aneurysms were enrolled in this study. Both microscopic fluorescence angiography and endoscopic fluorescein video angiography were performed before and after clip placement. RESULTS Endoscopic fluorescein video angiography provided bright fluorescence imaging even with a 2.7-mm-diameter endoscope and clearly revealed blood flow within the vessels in the dead angle areas of the microscope in all 18 aneurysms. Consequently, it revealed information about aneurysmal occlusion and perforator patency in 15 aneurysms (83.3%) that was not obtainable with microscopic fluorescence video angiography. Furthermore, only endoscopic video angiography detected the incomplete clipping in 2 aneurysms and the occlusion of the perforating branches in 3 aneurysms, which led to the reapplication of clips in 2 aneurysms. CONCLUSION The innovative endoscopic fluorescein video angiography system we developed features a small-caliber endoscope and bright fluorescence images. Because it reveals blood flow in the dead angle areas of the microscope, this novel system could contribute to the safety and long-term effectiveness of aneurysm surgery even in a narrow operative field.
Understanding the essential proton-pumping kinetic gates and decoupling mutations in cytochrome c oxidase

Significance Understanding the molecular mechanism that enables the high proton-pumping efficiency of cytochrome c oxidase (CcO) is not only fundamentally important but also potentially useful in providing design principles for bio-inspired materials. To this end, much effort has been devoted to the D-channel mutants of CcO that impair proton pumping. In this study, we have used multiscale reactive molecular dynamics simulations to explicitly characterize the free-energy profiles of proton transport (PT) through the D-channel for several important mutants. Our results show that both the fast forward rate and the slow backward rate of PT in the D-channel are important kinetic gating elements to achieve high proton-pumping efficiency, the latter of which has been largely overlooked to date. Cytochrome c oxidase (CcO) catalyzes the reduction of oxygen to water and uses the released free energy to pump protons against the transmembrane proton gradient. To better understand the proton-pumping mechanism of the wild-type (WT) CcO, much attention has been given to the mutation of amino acid residues along the proton translocating D-channel that impair, and sometimes decouple, proton pumping from the chemical catalysis. Although their influence has been clearly demonstrated experimentally, the underlying molecular mechanisms of these mutants remain unknown. In this work, we report multiscale reactive molecular dynamics simulations that characterize the free-energy profiles of explicit proton transport through several important D-channel mutants. Our results elucidate the mechanisms by which proton pumping is impaired, thus revealing key kinetic gating features in CcO. In the N139T and N139C mutants, proton back leakage through the D-channel is kinetically favored over proton pumping due to the loss of a kinetic gate in the N139 region. In the N139L mutant, the bulky L139 side chain inhibits timely reprotonation of E286 through the D-channel, which impairs both proton pumping and the chemical reaction. In the S200V/S201V double mutant, the proton affinity of E286 is increased, which slows down both proton pumping and the chemical catalysis. This work thus not only provides insight into the decoupling mechanisms of CcO mutants, but also explains how kinetic gating in the D-channel is imperative to achieving high proton-pumping efficiency in the WT CcO.