A Moderate Increase of Physiological CO2 in a Critical Range during Stable NREM Sleep Episode: A Potential Gateway to REM Sleep

Sleep is characterized as rapid eye movement (REM) and non-rapid eye movement (NREM) sleep. Studies suggest that wake-related neurons in the basal forebrain, posterior hypothalamus and brainstem, and NREM sleep-related neurons in the anterior-hypothalamic area inhibit each other, thus alternating sleep–wakefulness. Similarly, pontine REM-ON and REM-OFF neurons reciprocally inhibit each other for REM sleep modulation. It has been proposed that inhibition of locus coeruleus (LC) REM-OFF neurons is pre-requisite for REM sleep genesis, but it remains ambiguous how REM-OFF neurons are hyperpolarized at REM sleep onset. The frequency of breathing pattern remains high during wake, slows down during NREM sleep but further escalates during REM sleep. As a result, brain CO2 level increases during NREM sleep, which may alter REM sleep manifestation. It has been reported that hypocapnia decreases REM sleep while hypercapnia increases REM sleep periods. The groups of brainstem chemosensory neurons, including those present in LC, sense the alteration in CO2 level and respond accordingly. For example, one group of LC neurons depolarize while other hyperpolarize during hypercapnia. In another group, hypercapnia initially depolarizes but later hyperpolarizes LC neurons. Besides chemosensory functions, LC REM-OFF neurons are an integral part of REM sleep executive machinery. We reason that increased CO2 level during a stable NREM sleep period may hyperpolarize LC neurons including REM-OFF, which may help initiate REM sleep. We propose that REM sleep might act as a sentinel to help maintain normal CO2 level for unperturbed sleep

YY1 Is Required for Germinal Center B Cell Development.

YY1 has been implicated as a master regulator of germinal center B cell development as YY1 binding sites are frequently present in promoters of germinal center-expressed genes. YY1 is known to be important for other stages of B cell development including the pro-B and pre-B cells stages. To determine if YY1 plays a critical role in germinal center development, we evaluated YY1 expression during B cell development, and used a YY1 conditional knock-out approach for deletion of YY1 in germinal center B cells (CRE driven by the immunoglobulin heavy chain γ1 switch region promoter; γ1-CRE). We found that YY1 is most highly expressed in germinal center B cells and is increased 3 fold in splenic B cells activated by treatment with anti-IgM and anti-CD40. In addition, deletion of the yy1 gene by action of γ1-CRE recombinase resulted in significant loss of GC cells in both un-immunized and immunized contexts with corresponding loss of serum IgG1. Our results show a crucial role for YY1 in the germinal center reaction

Environmental nanotechnological applications for Sustainable agriculture

Agriculture and society are intertwined. Agriculture is necessary for human survival and social sustainability in India. Eco-friendly agriculture practices nurture ecosystems to solve current societal issues. Indian ecosystems are marred by pollution, imbalance, climate changes, food crisis, various diseases, and mal-nourishment continue as a major concern. The traditional environmental remedial strategies appear relatively ineffective in the ever expanding use of pollutants that pervade the water, air and soil environment. Nanotechnology provides an efficient, environmentally friendly and cost-effective solutions to the global sustainability challenges that society is facing. Nanotechnology utilizes nanomaterials that have remarkable physical and chemical features to make smart functional materials for developing sustainable technologies. Nanotechnology seems to be very promising in sustainable environment development, sustainable agriculture, renewable and economically energy alternative through use of nanomaterials for detection, prevention, and removing pollutants. The development of nanotechnology in India has huge potential to address the challenges like providing drinking water, healthcare, nano-based industry and sustainable agriculture. This review highlights the recent nanotechnology applications to meet the global challenges in providing clean energy technology, water purification, and greenhouse gases management. In addition, effort has been made to analyse the opportunities and limitations in engineered nanomaterials safety, solid waste management, reducing pollution of air water and soil

The prevalence of sleep loss and sleep disorders in young and old adults

The ability to sleep declines with age. The National Sleep Foundation, USA has recommended a minimum sleep amount for all ages. Individuals who experience sleep lesser than the recommended amount could be sleep-deprived. Several factors like stress, altered circadian cycle, medical conditions, etc. cause sleep deficiency. Almost 50–60 % of elderly population suffer from sleep disorders such as sleep apnea, restless legs syndrome, REM sleep behavior disorder, etc. Chronic sleep deprivation may further lead to the development of diseases such as Alzheimer's and Parkinson's. This paper reviews the prevalence of sleep disorders and consequences of sleep loss in young and old adults

Complementary Role of CD4+ T Cells in Response to Pneumococcal Polysaccharide Vaccines in Humans

Bacterial pathogens expressing capsular polysaccharides are common causes of mucosal infections (pneumonia, intestinal), as well as often fatal, invasive infections (meningitis, bloodstream infections) in children and adults worldwide. These chemically simple but structurally complex carbohydrate structures on the bacterial surface confer resistance to recognition and clearance by the immune system through a range of mechanisms. Such recognition of capsular polysaccharides may be reduced by their limited ability to directly stimulate B cells and the T cells that may facilitate these humoral responses. The capsules may promote the evasion of complement deposition and activation and may sterically shield the recognition of other subjacent protein antigens by innate factors. Antibodies to capsular polysaccharides, elicited by infection and vaccines, may overcome these obstacles and facilitate bacterial agglutination at mucosal surfaces, as well as the opsonization and clearance of these organisms in tissues and the systemic compartment. However, the immunogenicity of these antigens may be limited by their lack of direct recognition by T cells (“T-independent„ antigens) and their restricted ability to generate effective memory responses. In this review, we consider the mechanisms by which polysaccharides may initiate B cell responses and specific antibody responses and the role of T cells, particularly CD4+ follicular helper (TFH) cells to support this process. In addition, we also consider more recent counterintuitive data that capsular polysaccharides themselves may bind major histocompatibility antigen HLA class II to provide a more physiologic mechanism of T cell enhancement of B cell responses to capsular polysaccharides. Defining the contributions of T cells in the generation of effective humoral responses to the capsular polysaccharides will have important implications for understanding and translating this immunobiology for the development of more effective vaccines, to prevent the morbidity and mortality associated with these common mucosal and invasive pathogens in populations at risk

XPS, UV–Vis, FTIR, and EXAFS Studies to Investigate the Binding Mechanism of N719 Dye onto Oxalic Acid Treated TiO2TiO_{2} and Its Implication on Photovoltaic Properties

The anchoring mechanism of N719 dye molecules on oxalic acid treated TiO2 (OA-TiO2) electrodes has been investigated using extended X-ray absorption fine structure (EXAFS) measurements, Fourier transform infrared spectroscopy (FTIR), UV−vis spectroscopy, and X-ray photoelectron spectroscopy (XPS). The FTIR spectroscopy of OA-TiO2 electrodes revealed that the oxalic acid dissociates at the TiO2 surface and binds through bidentate chelating and/ or bidentate bridging. Analyses of EXAFS, FTIR, UV−vis, and XPS measurements of N719 dye loaded onto OA-TiO2 revealed that the binding of N719 molecules takes place via interaction between the Ru atom of the dye and O− of bidentate bridged oxalate ions at the TiO2 surface. This mechanism is quite different from the binding of N719 onto untreated TiO2 (WO-TiO2) surface, where −COOH and SCN groups of the dye directly bind to the TiO2 surface. The analyses of UV−vis data show that the amount of N719 dye loading onto OA-TiO2 surface is much higher than that onto the native TiO2 surface. In addition, the incident photon-to-current conversion efficiency (IPCE) measurements show that the presence of oxalate ions between the dye and TiO2 surface favors efficient electron transfer and therefore improvement in device efficiency. The dye-sensitized solar cells fabricated using N719 dye sensitized onto OA-TiO2 showed an efficiency of ∼4.6%, which is significantly higher than that based on a WO-TiO2 electrode (∼3.2%)

YY1 is required for antigen-specific germinal center development and for generation of antigen-specific IgG1.

<p><b>(A)</b> Splenocytes from NP-CGG immunized <i>γ1CRE</i> and <i>YY1</i>^<i>f/</i>f <i>γ1CRE</i> mice were harvested at 14 days after immunization and stained with various antibodies, as well as PNA to detect GC B cells. We gated on CD4⁻CD8⁻F4/80⁻Gr1⁻(DUMP⁻) IgD^- cells that were subdivided into PNA⁺B220⁺ GC-B cells. GC-B cells were gated and further subsetted into NP-specific (NP⁺B220⁺) GC-B cells. Representative results are from three independent experiments. <b>(B)</b> Numbers of NP-specific (NP⁺B220⁺) GC-B cells per spleen of immunized mice (<i>n</i> = 3). <b>(C)</b> <i>γ1CRE</i> and <i>YY1</i>^<i>f/</i>f <i>γ1CRE</i> mice were immunized with NP-CGG, and 14 days later spleen sections were stained with anti-GL7, anti-IgD and anti-TCRβ antibody. GL7-rich regions demarcate germinal center B cells. <b>(D, E)</b> Serum from NP-CGG immunized <i>γ1CRE</i> and <i>YY1</i>^<i>f/</i>f <i>γ1CRE</i> mice were collected at 14 days after immunization and NP-specific serum Igs were analyzed using ELISA. <i>D</i>. The concentration of low affinity (NP26, left panel) and high affinity (NP4, right panel) IgG1 in the serum. <i>E</i>. Titer of NP-specific total IgM in the sera of immunized mice. Data are derived from sera samples that were obtained from three experiments. Asterisks indicate p<0.001.</p

YY1 is required for germinal center B cell development and immunoglobulin class switching.

<p><b>(A)</b> Spleen cells from non-immunized <i>YY1</i>^<i>f/</i>, <i>γ1CRE</i> and <i>YY1</i>^<i>f/</i>f <i>γ1CRE</i> mice were stained with various antibodies to identify total B cells (CD19⁺AA4.1⁺, upper panel) and germinal center B cells (GC-B, DUMP^-IgD^-GL7^hiCD95^hi, lower panel). Percentages and number of <b>(B)</b> total B cells, and <b>(C)</b> GC-B cells per spleen of <i>YY1</i>^<i>f/</i>, <i>γ1CRE</i> and <i>YY1</i>^<i>f/</i>f <i>γ1CRE</i> mice. Fig A-C are from three independent experiments (<i>n</i> = 3 mice for each genotype). <b>(D)</b> We used ELISA to detect various isotypes of serum immunoglobulins from <i>YY1</i>^<i>f/</i>, <i>γ1CRE</i> and <i>YY1</i>^<i>f/</i>f <i>γ1CRE</i> mice. The concentration of IgM, IgA, total IgG, as well as IgG subclasses, IgG1, IgG2 and IgG3 were measured from sera samples that were obtained from four experiments (<i>n</i> ≥ 4 mice for each genotype). Asterisks indicate p<0.001.</p