Macrophage Uptake,Intracellular Localization,and Degradation of Poly-γ-d-Glutamic Acid,the Capsular Antigen of Bacillus anthracis

Bacillus anthracis is surrounded by a capsular polypeptide composed of poly-γ-d-glutamic acid (PGA). This antiphagocytic capsule is an essential virulence factor and is shed into body fluids during a murine model of pulmonary anthrax. Our previous studies of a murine model for antigen clearance showed that purified PGA accumulates in the liver and spleen, most notably in splenic macrophages and the Kupffer cells and sinusoidal endothelial cells of the liver. Although the tissue and cellular depots have been identified, there is little known about the uptake and intracellular fate of PGA. As a consequence, we examined the cellular uptake and organelle localization of PGA in the murine macrophage-like cell line J774.2. We found that PGA binds to and is internalized by J774.2 cells and accumulates in CD71 transferrin receptor-positive endosomes. The receptor-mediated endocytosis inhibitors amantadine and phenylarsine oxide inhibited the binding and uptake of PGA in these cells. Cytochalasin D and vinblastine, actin and microtubule inhibitors, respectively, failed to completely inhibit binding and uptake. Finally, we found that PGA is degraded in J774.2 cells starting 4 h after uptake, with continued degradation occurring for at least 24 h. This degradation of PGA may explain the rapid clearance of PGA that is observed in vivo compared to the slow clearance noted with capsular polysaccharides.Bacillus anthracis, the causative agent of anthrax, is surrounded by an antiphagocytic capsule that is an essential virulence factor (7, 13, 32). The capsule is unusual because it is composed of poly-γ-d-glutamic acid (PGA) (12); encapsulated bacteria are typically surrounded by a polysaccharide capsule. PGA is shed into body fluids in high concentrations during a murine model of pulmonary anthrax (15). However, our previous studies also found that purified PGA is rapidly cleared from the blood (24 h) in mice (28). This rapid clearance contrasts with the much slower in vivo clearance of capsular polysaccharides which remain in the blood for several days (11, 28). PGA is also rapidly cleared from tissues, with the complete clearance of measurable antigen after 21 days, and excreted into the urine as fragments of heterogeneous size (28). In contrast, Kaplan et al. found that pneumococcal polysaccharide remains in murine tissues up to 75 days (14).Previous studies of a murine model of antigen clearance showed that purified PGA accumulates in the liver, specifically in the Kupffer cells and the sinusoidal endothelial cells (28), with smaller amounts of PGA in the splenic macrophages. However, the intracellular location and kinetics for the uptake of PGA by host cells are not known. Macrophages ingest particles and macromolecules via several different pathways, including phagocytosis, pinocytosis, and receptor-mediated endocytosis (5). Although each of these pathways may be unique to the object being endocytosed, once inside, the general trafficking pathways are similar. Typically, molecules are endocytosed and taken from early endosomes to late endosomes and onto the lysosome for degradation (22). Although most molecules follow this pathway, some proteins, including transferrin, are recycled back to the plasma membrane via the recycling endosomal pathway (1). In addition, some proteins, such as cholera toxin, undergo retrograde transport from the early endosomes, back to the trans-Golgi network (25, 26).In an attempt to better understand the intracellular trafficking of PGA, we examined the kinetics for uptake and the intracellular location of PGA in the macrophage-like cell line J774.2. In addition, microtubule, actin, and receptor-mediated endocytosis inhibitors were used to examine the potential mechanisms for PGA binding and uptake. Glucuronoxylomannan (GXM), the capsular polysaccharide from Cryptococcus neoformans, was used as a model for comparison of the uptake of polypeptide versus polysaccharide capsular antigens. Our results show that PGA is taken up and trafficked through the recycling endosomes; such transport can be blocked by inhibitors of receptor-mediated endocytosis.     

Effects of α-Glucosylhesperidin,a Bioactive Food Material,on Collagen-Induced Arthritis in Mice and Rheumatoid Arthritis in Humans

Hesperidin (Hsp) is an abundant flavonoid in citrus fruits, and the oral administration of Hsp has been recently reported to suppress collagen-induced arthritis in mice. Therefore, we sought to determine whether α-glucosylhesperidin (Hsp-G), which is an Hsp derivative with enhanced water-solubility, is effective on treating arthritis in both mice and humans. Hsp-G was orally administered to mice with collagen-induced arthritis, and its effects were evaluated clinically and histologically. Oral administration of Hsp-G improved collagen-induced arthritis when administered before the onset of arthritis as well as when administered after its onset. A decrease in tumor necrosis factor-α production was found to cause this improvement. In the human study, 19 patients with rheumatoid arthritis (RA) were enrolled in a 12-week double-blind, placebo-controlled trial. Patients were administered beverages containing 3 g Hsp-G (n?=?9) or placebo (n?=?10) every morning for the duration of the 3-month trial. Additionally, patients received standard therapy from a physician every 4 weeks. As a result, 3 of 9 patients in the Hsp-G group improved, while only 1 of 10 patients in the placebo group improved; this was in accordance with the American College of Rheumatology criteria. The present study revealed that the food material Hsp-G was effective when administered with standard anti-rheumatoid therapy in ameliorating RA in mice and humans without any adverse effects and may improve the quality of life for patients with RA as a complementary/alternative medicine.     

Antecedents, Concomitants, and Consequences of Pediatric Headache: Confirmatory Construct Validation of Two Parent–Report Scales

The aim of the study presented is to examine the psychometric properties of two parent–report scales for the assessment of environmental factors in pediatric headache, namely, the Children's Headache Assessment Scale (CHAS) and the Illness Behavior Encouragement Scale (IBES). Data were gathered in a sample of 160 parents of children suffering from headaches regularly. The internal structure of both scales is investigated by means of confirmatory factor analysis. The internal consistency of the resulting subscales is explored and data on the convergent validity and on the relationship with demographics are presented. Both the CHAS and the IBES appear to be promising assessment tools in a behavioral approach to pediatric headache.     

Fabrication, Characterization and In Vitro Evaluation of Aligned PLGA–PCL Nanofibers for Neural Regeneration

Electrospun nanofibrous scaffolds have received a great deal of attention in tissue engineering in recent years. Bridging larger nerve gaps between proximal and distal ends requires exogenous tubular constructs with uniaxially aligned topographical cues to promote the axonal re-growth due to the lack of fibrin cable formation. In this study, we have designed and developed a collector to obtain aligned nanofibers of PLGA-PCL. The average diameter of the fibers obtained is 230?±?63?nm and the alignment of fibers is quantified by calculating relative angle of each fiber. The tensile strength, porosity, contact angle, and biodegradation of the uniaxial PLGA-PCL nanofibers are measured and compared with the corresponding random fibers. Pore size, Young's modulus, and degradation of the aligned scaffold are significantly lesser than random fibers (p?相似文献   

Intestinal Behçet’s Disease: Epidemiology, Pathophysiology and Potential of Mesalazine

Behçet’s disease (BD) is a systemic inflammatory disease of unknown origin that affects various parts of the body. In some patients, the prognosis of the disease appears to be altered by the involvement of the intestine (intestinal BD). In intestinal BD, deep ulcers develop in the gastrointestinal tract, typically in the ileocaecum. Intestinal lesions in patients with BD are much more common in countries in the Far East, especially Japan. The tissue damage occurring in patients with BD is believed to be caused by oxygen radicals, which are promoted by proinflammatory cytokines and arachidonic acid metabolites. New formulations of mesalazine (5-aminosalicylic acid; 5-ASA) are now available for the treatment of intestinal BD. Mesalazine breaks the chain reaction of free radical production. Mesalazine may provide an effective treatment for the promotion of long term healing of mucosal ulceration of the intestine in patients with BD.     

Spred1, a negative regulator of Ras�CMAPK�CERK, is enriched in CNS germinal zones, dampens NSC proliferation, and maintains ventricular zone structure

Neural stem cells (NSCs) have great potential for self-renewal, which must be tightly regulated to generate appropriate cell numbers during development and to prevent tumor formation. The Ras–MAPK–ERK pathway affects mitogen-stimulated proliferation, and negative regulators are likely to be important for keeping self-renewal in check. Sprouty-related protein with an EVH1 domain (Spred1) is a recently discovered negative Ras–MAPK–ERK regulator linked to a neurofibromatosis 1 (NF-1)-like human syndrome; however, its role in CNS development has not been explored. We show that Spred1 is highly enriched in CNS germinal zones during neurogenesis. Spred1 knockdown increases NSC self-renewal and progenitor proliferation cell-autonomously, and overexpression causes premature differentiation. Surprisingly, Spred1 knockdown in vivo in the embryonic mouse forebrain frequently resulted in periventricular heterotopia, developmental abnormalities often associated with mutations in genes in the vesicular trafficking pathway that cause disruption of germinal zones and impair cell migration. In cortical progenitor cells, Spred1 localizes within distinct vesicles, indicating a potential role in transport. Spred1 knockdown gradually leads to disruption of the apical ventricular zone and loss of radial glia alignment. This impairs late neuronal migration, resulting in the formation of periventricular masses. Thus, Spred1 is critical for normal cortical development, as it modulates progenitor self-renewal/proliferation and helps maintain the integrity and organization of germinal zones.     

Attenuation of 7-ketocholesterol- and 7β-hydroxycholesterol-induced oxiapoptophagy by nutrients,synthetic molecules and oils: Potential for the prevention of age-related diseases

Age-related diseases for which there are no effective treatments include cardiovascular diseases; neurodegenerative diseases such as Alzheimer's disease; eye disorders such as cataract and age-related macular degeneration; and, more recently, Severe Acute Respiratory Syndrome (SARS-CoV-2). These diseases are associated with plasma and/or tissue increases in cholesterol derivatives mainly formed by auto-oxidation: 7-ketocholesterol, also known as 7-oxo-cholesterol, and 7β-hydroxycholesterol. The formation of these oxysterols can be considered as a consequence of mitochondrial and peroxisomal dysfunction, leading to increased in oxidative stress, which is accentuated with age. 7-ketocholesterol and 7β-hydroxycholesterol cause a specific form of cytotoxic activity defined as oxiapoptophagy, including oxidative stress and induction of death by apoptosis associated with autophagic criteria. Oxiaptophagy is associated with organelle dysfunction and in particular with mitochondrial and peroxisomal alterations involved in the induction of cell death and in the rupture of redox balance. As the criteria characterizing 7-ketocholesterol- and 7β-hydroxycholesterol-induced cytotoxicity are often simultaneously observed in major age-related diseases (cardiovascular diseases, age-related macular degeneration, Alzheimer’s disease) the involvement of these oxysterols in the pathophysiology of the latter seems increasingly likely. It is therefore important to better understand the signalling pathways associated with the toxicity of 7-ketocholesterol and 7β-hydroxycholesterol in order to identify pharmacological targets, nutrients and synthetic molecules attenuating or inhibiting the cytotoxic activities of these oxysterols. Numerous natural cytoprotective compounds have been identified: vitamins, fatty acids, polyphenols, terpenes, vegetal pigments, antioxidants, mixtures of compounds (oils, plant extracts) and bacterial enzymes. However, few synthetic molecules are able to prevent 7-ketocholesterol- and/or 7β-hydroxycholesterol-induced cytotoxicity: dimethyl fumarate, monomethyl fumarate, the tyrosine kinase inhibitor AG126, memantine, simvastatine, Trolox, dimethylsufoxide, mangafodipir and mitochondrial permeability transition pore (MPTP) inhibitors. The effectiveness of these compounds, several of which are already in use in humans, makes it possible to consider using them for the treatment of certain age-related diseases associated with increased plasma and/or tissue levels of 7-ketocholesterol and/or 7β-hydroxycholesterol.     

Two QTLs Located on Chromosomes 1 and 5 Modulate Different Aspects of the Performance of Mice of the B × D Ty RI Strain Series in the Morris Navigation Task

The Morris navigation task is widely used to study spatial abilities in rodents; namely, to analyze the effects of mutations in genetically engineered mice. Although quantitative and Mendelian genetic studies have shown that the variation of these abilities is partly under genetic control, little is known about these genetic factors. In order to analyze the genetic architecture of spatial navigation in mice, a wide genome scan was performed to map the QTLs that control various aspects of the performance, using the RI strain methodology. Latencies to locate the submerged platform across learning sessions and performance to the spatial probe test were analyzed in the 26 strains of the B × D RI series. Both cluster analysis of behavioral measurements and QTL mapping confirmed previous data showing that the escape latencies and the spatial bias rely on two distinct components of the task, controlled by different loci. A QTL on chromosome 1 influenced escape latencies during the four training sessions, whereas another QTL, located on chromosome 5, was shown to control spatial performance at the probe trial and also exhibited epistatic interactions with two other QTLs on chromosomes 2 and 13. The function of these QTLs is examined in the broader context of hippocampal-dependent learning processes and in relation to QTLs already found in similar positions in other behavioral traits.     

Localization of Sources Generating the EEG α Rhythm during Observation,Performance, and Imitation of Operant Movements in Subjects with Different Intelligence Levels

Neuroscience and Behavioral Physiology - Use of the sLORETA method in 62 adult subjects with different intelligence levels located sources generating rhythms in the frequency band 8–12 Hz...     

Blood Specimen Biomarkers of Inflammation, Matrix Degradation, Angiogenesis, and Cardiac Involvement: a Future Useful Tool in Assessing Clinical Outcomes of COPD Patients in Clinical Practice?

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation that is not fully reversible; this airflow limitation is both progressive and associated with an abnormal inflammatory response of the lung to noxious particles or gasses. COPD is undoubtedly an umbrella term, and it seems unlikely that all patients with COPD have the same underlying disease processes; thus, there is a need for differential treatment of different subgroups. A potential solution is to find modifiable biomarkers that can assist in drug development and distinguish subgroups of COPD. With the exception of lung function tests, there are currently no well-validated biomarkers or surrogate endpoints that can be used to establish the efficacy of a drug for COPD. This article discusses biomarkers of inflammation (fibrinogen, C-reactive protein, pulmonary and activation-regulated chemokine/CC-chemokine ligand-18, serum surfactant protein D, interleukin (IL)-6, IL-8 and tumor necrosis factor α, complement factor C5a), angiogenesis factors as a part of the pathogenetic aspect in this disease (vascular endothelial growth factor, angiogenin, and IL-8), and matrix degradation biomarkers. Troponin and natriuretic peptides are presented as biomarkers of cardiac involvement in the light of COPD comorbidities. Trials based on research on known clinical variables such as FEV1, BODE, and 6MWT in combination with biomarkers from lung and blood specimens will probably clarify part of the prognosis and natural history of the disease. This will also represent an additional step in COPD phenotyping and new treatment possibilities.     

Are Different Individuals Sensitive to Different Environments? Individual Differences in Sensitivity to the Effects of the Parent,Peer and School Environment on Externalizing Behavior and its Genetic and Environmental Etiology

Behavior Genetics - Externalizing behavior is substantially affected by genetic effects, which are moderated by environmental exposures. However, little is known about whether these moderation...     

The Chemistry of Famine: Nutritional Controversies and the Irish Famine, c.1845�C7

The activities of Irish medical practitioners in relieving the impact of the Irish Famine (c.1845–52) have been well documented. However, analysis of the function of contemporary medico-scientific ideas relating to food has remained mostly absent from Famine historiography. This is surprising, given the burgeoning influence of Liebigian chemistry and the rising social prominence of nutritional science in the 1840s. Within this article, I argue that the Famine opened up avenues for advocates of the social value of nutritional science to engage with politico-economic discussion regarding Irish dietary, social and economic transformation. Nutritional science was prominent within the activities of the Scientific Commission, the Central Board of Health and in debates regarding soup kitchen schemes. However, the practical inefficacy of many scientific suggestions resulted in public associations being forged between nutritional science and the inefficiencies of state relief policy, whilst emergent tensions between the state, science and the public encouraged scientists in Ireland to gradually distance themselves from state-sponsored relief practices.     

The Therapeutic Potential, Challenges and Future Clinical Directions of Stem Cells from the Wharton’s Jelly of the Human Umbilical Cord

Mesenchymal stem cells (MSCs) from bone marrow, adult organs and fetuses face the disadvantages of invasive isolation, limited cell numbers and ethical constraints while embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) face the clinical hurdles of potential immunorejection and tumorigenesis respectively. These challenges have prompted interest in the study and evaluation of stem cells from birth-associated tissues. The umbilical cord (UC) has been the most popular. Hematopoietic stem cells (HSCs) harvested from cord blood have been successfully used for the treatment of hematopoietic diseases. Stem cell populations have also been reported in other compartments of the UC viz., amnion, subamnion, perivascular region, Wharton’s jelly, umbilical blood vessel adventia and endothelium. Differences in stemness characteristics between compartments have been reported and hence derivation protocols using whole UC pieces containing all compartments yield mixed stem cell populations with varied characteristics. Stem cells derived directly from the uncontaminated Wharton’s jelly (hWJSCs) appear to offer the best clinical utility because of their unique beneficial properties. They are non-controversial, can be harvested painlessly in abundance, proliferative, possess stemness properties that last several passages in vitro, multipotent, hypoimmunogenic and do not induce tumorigenesis even though they have some ESC markers. hWJSCs and its extracts (conditioned medium and lysate) also possess anti-cancer properties and support HSC expansion ex vivo. They are thus attractive autologous or allogeneic agents for the treatment of malignant and non-malignant hematopoietic and non-hematopoietic diseases. This review critically evaluates their therapeutic value, the challenges and future directions for their clinical application.     

Two brothers with macrocephaly, progressive cerebral atrophy and abnormal white matter, severe mental retardation, and Lennox-Gastaut spectrum type epilepsy: an inherited encephalopathy of childhood?

Two brothers with severe mental retardation of unknown origin were found to share several physical anomalies, including large round head, small concave nose, downslanted palpebral fissures, and gingival hyperplasia. In addition to relative macrocephaly, magnetic resonance imaging (MRI) showed severe cerebral atrophy, especially fronto-temporally. The brothers also had a thin corpus callosum and atrophic caudate nuclei. The reduced white matter showed patchy periventricular signal intensity changes. The lateral and third ventricles were large, but the fourth ventricle was of normal size. The boys had large cisterna magna, communicating widely with the fourth ventricle, but no vermian hypoplasia. Both boys had Lennox-Gastaut spectrum type epilepsy. No chromosomal anomalies were found, despite the suggestive clinical picture. Some of the clinical findings resembled fetal alcohol effects/fetal alcohol syndrome (FAE/FAS), which was also suggested by history. Current diagnostic criteria for FAE/FAS, however, excluded full-blown FAS in these cases and failed to explain the entire clinical picture in the boys. We argue that these boys had an unidentified inherited syndrome, possibly modified by fetal alcohol exposure.