We report the case of an 85-year-old patient who developed trifascicular block with syncope, triggered by preoperative eye drops for cataract surgery. This life-threatening situation reopens the debate over the necessity of having an anesthesiologist present during cataract surgery.Nous présentons le cas d’un patient de 85 ans, ayant présenté un bloc trifasciculaire avec syncopes déclenché par les collyres préopératoires avant une chirurgie de la cataracte. Cette situation à risque vital pour le patient relance le débat sur la nécessité d’avoir un anesthésiste disponible pour une chirurgie de cataracte.
We recently reported that trace insertion of exogenous fluorescent (green BODIPY) analogs of sphingomyelin (SM) into living red blood cells (RBCs), partially spread onto coverslips, labels submicrometric domains, visible by confocal microscopy. We here extend this feature to endogenous SM, upon binding of a SM-specific nontoxic (NT) fragment of the earthworm toxin, lysenin, fused to the red monomeric fluorescent protein, mCherry [construct named His-mCherry-NT-lysenin (lysenin*)]. Specificity of lysenin* binding was verified with composition-defined liposomes and by loss of 125I-lysenin* binding to erythrocytes upon SM depletion by SMase. The 125I-lysenin* binding isotherm indicated saturation at 3.5 × 106 molecules/RBC, i.e., ∼3% of SM coverage. Nonsaturating lysenin* concentration also labeled submicrometric domains on the plasma membrane of partially spread erythrocytes, colocalizing with inserted green BODIPY-SM, and abrogated by SMase. Lysenin*-labeled domains were stable in time and space and were regulated by temperature and cholesterol. The abundance, size, positioning, and segregation of lysenin*-labeled domains from other lipids (BODIPY-phosphatidylcholine or -glycosphingolipids) depended on membrane tension. Similar lysenin*-labeled domains were evidenced in RBCs gently suspended in 3D-gel. Taken together, these data demonstrate submicrometric compartmentation of endogenous SM at the membrane of a living cell in vitro, and suggest it may be a genuine feature of erythrocytes in vivo.
Severe, progressive skeletal dysplasia is a major symptom of multiple mucopolysaccharidoses (MPS) types. While a gene therapy approach initiated at birth has been shown to prevent the development of bone pathology in different animal models of MPS, the capacity to correct developed bone disease is unknown. In this study, ex vivo micro-computed tomography was used to demonstrate that bone mass and architecture of murine MPS VII L5 vertebrae were within the normal range at 1 month of age but by 2 months of age were significantly different to normal. The difference between normal and MPS VII BV/TV increased with age reaching a maximal difference at approximately 4 months of age. In mature MPS VII bone BV/TV is increased (51.5% versus 21.5% in normal mice) due to an increase in trabecular number (6.2 per mm versus 3.8 per mm in normal mice). The total number of osteoclasts in the metaphysis of MPS VII mice was decreased, as was the percentage of osteoclasts attached to bone. MPS VII osteoblasts produced significantly more osteoprotegerin (OPG) than normal osteoblasts and supported the production of fewer osteoclasts from spleen precursor cells than normal osteoblasts in a co-culture system. In contrast, the formation of osteoclasts from MPS VII spleen monocytes was similar to normal in vitro, when exogenous RANKL and m-CSF was added to the culture medium. Administration of murine β-glucuronidase to MPS VII mice at 4 months of age, when bone disease was fully manifested, using lentiviral gene delivery resulted in a doubling of osteoclast numbers and a significant increase in attachment capacity (68% versus 29.4% in untreated MPS VII animals). Bone mineral volume rapidly decreased by 39% after gene therapy and fell within the normal range by 6 months of age. Collectively, these results indicate that lentiviral-mediated gene therapy is effective in reversing established skeletal pathology in murine MPS VII.
Figurative language is one of the most prevalent expressions of verbal creativity, and use of novel metaphors is the most significant source of verbal innovation. As environmental and personality trait factors can impact creativity, the current study aimed to examine whether exposure to an environment rich in visual stimuli (artwork) and verbal stimuli (novel metaphors) contributes to verbal creativity, taking into account the personality trait of “openness to experience.” Study participants (132) were divided into three groups: (1) a group exposed to a creative verbal environment (reading novel metaphors), (2) a group exposed to a visually creative environment (observing abstract and figurative artwork), and (3) a group not exposed to any creative environment. Participants completed personality questionnaire and a metaphor generation questionnaire that asked participants to describe 10 emotions using novel metaphors. Results showed the type of creative environment exposure had a graded effect on creativity (i.e., generation of novel metaphors): the non-exposed control group generated fewer novel than conventional metaphors, the group exposed to novel verbal metaphors produced a similar number of novel and conventional metaphors, and the group exposed to artwork produced more novel than conventional metaphors. This may imply that environments containing visually creative stimuli provide opportunities for silent contemplation which in turn evoke neuropsychological mechanisms related to creative processes. Furthermore, the finding that the trait of “openness to experience” and exposure to a visually creative environment contributed to greater generation of novel metaphors suggests that creativity may be dependent on both individual and environmental factors.
GM1-gangliosidosis is a catastrophic, neurodegenerative lysosomal storage disease caused by a deficiency of lysosomal β-galactosidase (β-Gal). The primary substrate of the enzyme is GM1-ganglioside (GM1), a sialylated glycosphingolipid abundant in nervous tissue. Patients with GM1-gangliosidosis present with massive and progressive accumulation of GM1 in the central nervous system (CNS), which leads to mental and motor decline, progressive neurodegeneration, and early death. No therapy is currently available for this lysosomal storage disease. Here, we describe a proof-of-concept preclinical study toward the development of enzyme replacement therapy (ERT) for GM1-gangliosidosis using a recombinant murine β-Gal fused to the plant lectin subunit B of ricin (mβ-Gal:RTB). We show that long-term, bi-weekly systemic injection of mβ-Gal:RTB in the β-Gal−/− mouse model resulted in widespread internalization of the enzyme by cells of visceral organs, with consequent restoration of enzyme activity. Most importantly, β-Gal activity was detected in several brain regions. This was accompanied by a reduction of accumulated GM1, reversal of neuroinflammation, and decrease in the apoptotic marker caspase 3. These results indicate that the RTB lectin delivery module enhances both the CNS-biodistribution pattern and the therapeutic efficacy of the β-Gal ERT, with the potential to translate to a clinical setting for the treatment of GM1-gangliosidosis.
The greatest challenges for therapeutic efficacy of many macromolecular drugs that act on intracellular are delivery to key organs and tissues and delivery into cells and subcellular compartments. Transport of drugs into critical cells associated with disease, including those in organs protected by restrictive biological barriers such as central nervous system (CNS), bone, and eye remains a significant hurdle to drug efficacy and impacts commercial risk and incentives for drug development for many diseases. These limitations expose a significant need for the development of novel strategies for macromolecule delivery. RTB lectin is the non-toxic carbohydrate-binding subunit B of ricin toxin with high affinity for galactose/galactosamine-containing glycolipids and glycoproteins common on human cell surfaces. RTB mediates endocytic uptake into mammalian cells by multiple routes exploiting both adsorptive-mediated and receptor-mediated mechanisms. In vivo biodistribution studies in lysosomal storage disease models provide evidence for the theory that the RTB-lectin transports corrective doses of enzymes across the blood-brain barrier to treat CNS pathologies. These results encompass significant implications for protein-based therapeutic approaches to address lysosomal and other diseases having strong CNS involvement.
Abstract: Motivated by the practical application of protein structur e-structure alignment, we have studied the problem of maximum common subgraph within the framework of parameteri zed complexity. We investigated the lower bound for the exact algorithms of the problem. We proved it is unlikely that there is an algorithm of time p(n,m)∗ko(m) for the problem, wherep is a polynomial function, k is a parameter of map width, and m andn are the numbers of vertices of the two graphs respectively. I n consideration of the upper bound of p(n,m)∗km based on the brute-force approach, our lower bound result is asymptotically tight. Although the algorithm with the running timep(n,m)∗km could not be significantly improved from our lower bound resu lt, it is still possible to develop efficient algorithms for the practical appl ication of the protein structure-structure alignment. We developed an efficient algorithm integrating the color co ding method and parameterized computation for identifying the maximum common subgraph of two protein stru cture graphs. We have applied the algorithm to protein structure-structure alignment and conducted ex perimental testing of more than 600 protein pairs. Our parameterized approach shows improvement in structure alignment efficiency and will be very useful for structure comparisons of proteins with large sizes.
In this review, we strive to persuade the reader that the concept of health involves not only curing or treating disease, but in creating a healthy environment. Technical innovation enables new approaches to harness plants for biofuels, remediation, pharmaceuticals, and other biobased products to solve global crises in disease and pollution. Solutions range from the individual (i.e. enzyme replacement therapy) to regional (i.e. superfund site remediation) to worldwide challenges in disease and environmental management.
In both multiple sclerosis and experimental autoimmune encephalomyelitis (EAE), the C-C chemokine receptor 6 (CCR6) is critical for pathogenic T helper 17 (Th17) cell migration to the central nervous system (CNS). Whereas many cytokines and their receptors are potently regulated via post-transcriptional mechanisms in response to various stimuli, how CCR6 expression is post-transcriptionally regulated in Th17 cells is unknown. Here, using RNA-binding protein HuR conditional knock-out (KO) and wild-type (WT) mice, we present evidence that HuR post-transcriptionally regulates CCR6 expression by binding to and stabilizing Ccr6 mRNA and by promoting CCR6 translation. We also found that HuR down-regulates several microRNA expressions, which could target the 3′-UTR of Ccr6 mRNA for decay. Accordingly, knock-out of HuR reduced CCR6 expression on Th17 cells and impaired their migration to CNS compared with the response of WT Th17 cells and thereby ameliorated EAE. Together, these findings highlight how HuR contributes to Th17 cell-mediated autoimmune neuroinflammation and support the notion that targeting HuR might be a potential therapeutic intervention for managing autoimmune disorders of the CNS.
Interest in elucidating the etiology of hernias has encouraged countless studies of musculoaponeurotic structures in individuals with and without hernias. Studies of hernia patients have firmly demonstrated a correlation between hernias and collagen alterations in their fascia. Diastasis recti is an increased width of the abdominal midline that is exclusively composed of interlacing aponeurotic expansions of the anterolateral abdominal muscles. The condition is common among women undergoing abdominoplasty, and many factors, not only mechanical, play a role. The goal of this study is to evaluate and compare collagen type I and III levels in the midline fascia of women with and without diastasis recti to report their possible influence on this condition.This is a case-control study nested within a surgical cohort of 18 women with diastasis recti and 18 women without the condition (cases and controls, respectively). Fascia from the midline of the abdominal wall was collected and analyzed through immunohistochemistry using polyclonal antibodies to collagen type I and III.Both type I and type III collagen were less abundant in women with diastasis recti than in those without the condition, and the difference was statistically significant (p<0.001).Low collagen type I and type III levels in the midline of the abdominal wall may play a key role in the development of diastasis recti.
Despite significant advances in the fabrication of bioengineered scaffolds for tissue engineering, delivery of nutrients in complex engineered human tissues remains a challenge. By taking advantage of the similarities in the vascular structure of plant and animal tissues, we developed decellularized plant tissue as a prevascularized scaffold for tissue engineering applications. Perfusion-based decellularization was modified for different plant species, providing different geometries of scaffolding. After decellularization, plant scaffolds remained patent and able to transport microparticles. Plant scaffolds were recellularized with human endothelial cells that colonized the inner surfaces of plant vasculature. Human mesenchymal stem cells and human pluripotent stem cell derived cardiomyocytes adhered to the outer surfaces of plant scaffolds. Cardiomyocytes demonstrated contractile function and calcium handling capabilities over the course of 21 days. These data demonstrate the potential of decellularized plants as scaffolds for tissue engineering, which could ultimately provide a cost-efficient, “green” technology for regenerating large volume vascularized tissue mass.
Most of membrane molecules including cell surface receptors and secreted proteins including ligands are glycoproteins and glycolipids. Therefore, identifying the functional significance of glycans is crucial for developing an understanding of cell signaling and subsequent physiological and pathological cellular events. In particular, the function of N-glycans associated with cell surface receptors has been extensively studied since they are directly involved in controlling cellular functions. In this review, we focus on the roles of glycosyltransferases that are involved in the modification of N-glycans and their target proteins such as epidermal growth factor receptor (EGFR), ErbB3, transforming growth factor β (TGF-β) receptor, T-cell receptors (TCR), β-site APP cleaving enzyme (BACE1), glucose transporter 2 (GLUT2), E-cadherin, and α5β1 integrin in relation to diseases and epithelial–mesenchymal transition (EMT) process. Above of those proteins are subjected to being modified by several glycosyltransferases such as N-acetylglucosaminyltransferase III (GnT-III), N-acetylglucosaminyltransferase IV (GnT-IV), N-acetylglucosaminyltransferase V (GnT-V), α2,6 sialyltransferase 1 (ST6GAL1), and α1,6 fucosyltransferase (Fut8), which are typical N-glycan branching enzymes and play pivotal roles in regulating the function of cell surface receptors in pathological cell signaling.
Glucocerebrosidase is a lysosomal hydrolase involved in the breakdown of glucosylceramide. Gaucher disease, a recessive lysosomal storage disorder, is caused by mutations in the gene GBA1. Dysfunctional glucocerebrosidase leads to accumulation of glucosylceramide and glycosylsphingosine in various cell types and organs. Mutations in GBA1 are also a common genetic risk factor for Parkinson disease and related synucleinopathies. In recent years, research on the pathophysiology of Gaucher disease, the molecular link between Gaucher and Parkinson disease, and novel therapeutics, have accelerated the need for relevant cell models with GBA1 mutations. While induced pluripotent stem cells, primary rodent neurons, and transfected neuroblastoma cell lines have been used to study the effect of glucocerebrosidase deficiency on neuronal function, these models have limitations because of challenges in culturing and propagating the cells, low yield, and the introduction of exogenous mutant GBA1. To address some of these difficulties, we established a high yield, easy-to-culture mouse neuronal cell model with nearly complete glucocerebrosidase deficiency representative of Gaucher disease. We successfully immortalized cortical neurons from embryonic null allele gba−/− mice and the control littermate (gba+/+) by infecting differentiated primary cortical neurons in culture with an EF1α-SV40T lentivirus. Immortalized gba−/− neurons lack glucocerebrosidase protein and enzyme activity, and exhibit a dramatic increase in glucosylceramide and glucosylsphingosine accumulation, enlarged lysosomes, and an impaired ATP-dependent calcium-influx response; these phenotypical characteristics were absent in gba+/+ neurons. This null allele gba−/− mouse neuronal model provides a much needed tool to study the pathophysiology of Gaucher disease and to evaluate new therapies.
Epilepsy with periodic and unpredictable seizures is associated with hippocampal glutamate toxicity and tissue reorganization. Astrocytes play an important role in mediating the neuroprotective effects of estradiol and reducing seizure severity. Accordingly, the protective effects of low and high doses of estradiol on behavioral, astrocytic involvement and neuronal survival aspects of Pilocarpine-induced epilepsy were investigated. Lithium- Pilocarpine (30 mg/kg) model was used to provoke epilepsy. Βeta-estradiol (2,40 μg/µl) was injected subcutaneously from 48 before to 48 h after seizure induction. Behavioral convulsions were then monitored and recorded on the day of induction. Four weeks later, glutamine synthetase (GS) activity and the astrocyte transporter GLT-1 expression of the hippocampus were measured. Moreover, hippocampal glutamate and GABA were evaluated to study excitability changes. Finally, neuronal counting in the hippocampus was also performed using Nissl staining. The latency for generalized clonic (GC) convulsions significantly increased while the rate of GC and death significantly reduced due to β-estradiol treatment. GS activity and GLT-1 expression increased in the groups receiving the high dose of β-estradiol and Pilocarpine. Furthermore, the amount of both GABA and glutamate content decreased due to high dose of estradiol, while only GABA increased in Pilocarpine treated rats. Finally, administration of β-estradiol with low and high doses increased and improved the density of nerve cells. It is concluded that chronic administration β-estradiol has anticonvulsant and neuroprotective properties which are plausibly linked to astrocytic activity.
GM1-gangliosidosis is an inherited autosomal recessive disorder caused by mutations in the gene GLB1, which encodes acid β-galactosidase (β-gal). The lack of activity in this lysosomal enzyme leads to accumulation of GM1 gangliosides (GM1) in cells. We have developed a high-content-imaging method to assess GM1 levels in fibroblasts that can be used to evaluate substrate reduction in treated GLB1(-/-) cells [1]. This assay allows fluorescent quantification in a multi-well system which generates unbiased and statistically significant data. Fluorescently labeled Cholera Toxin B subunit (CTXB), which specifically binds to GM1 gangliosides, was used to detect in situ GM1 levels in a fixed monolayer of fibroblasts. This sensitive, rapid, and inexpensive method facilitates in vitro drug screening in a format that allows a high number of replicates using low working volumes.
Interleukin-6 (IL-6) plays a crucial role in the pathogenesis of rheumatoid arthritis (RA). Both fulfillment of remission criteria and assessment of other methods of evaluation of RA are important for preventing joint damage progression. Measurement of serum IL-6 concentrations has been reported to be useful for monitoring RA disease activity. However, it takes at least 4–5 h to measure serum IL-6 concentrations using traditional methods, which limits its utility during routine assessment in daily clinical practice settings. We established a novel method that enables measurement of serum IL-6 within 24 min and requires a very small blood volume. We investigated the accuracy and efficacy of this system in RA patients.One hundred fifty blood samples collected from 76 patients were measured using the two systems. We first developed the prototype of the Human IL-6 RAYFAST. Then, we examined the correlation between the prototype RAYFAST and chemiluminescent enzyme immunoassay (CLEIA) methods. Finally, we compared IL-6 concentrations and clinical parameters using both systems.The correlation between RAYFAST (x) and CLEIA (y) for IL-6 was y = 0.895x − 5.94, r = 0.941 (p < 0.0001). Serum IL-6 concentrations in RAYFAST correlated with DAS28-CRP (r = 0.372, p < 0.05) and DAS28-ESR (r = 0.397, p < 0.01). Serum IL-6 concentrations in CLEIA correlated with DAS28-CRP (r = 0.313, p < 0.001) and DAS28-ESR (r = 0.353, p < 0.001).This new cytokine quick measure system is as accurate as CLEIA methods. Serum IL-6 concentrations can be measured in 24 min using the prototype RAYFAST. It might be usable in the daily clinical practice setting, thereby contributing to improved RA management.
Xiuzhen Huang合作论文数Department of Computer Science,;Arkansas State University.8