Neurite outgrowth from progeny of epidermal growth factor–responsive hippocampal stem cells is significantly less robust than from fetal hippocampal cells following grafting onto organotypic hippocampal slice cultures: Effect of brain‐derived neurotrophic factor

Epidermal growth factor (EGF)–responsive stem cells from both developing and adult central nervous system (CNS) can be expanded and induced to differentiate into neurons and glia in vitro. Because of their self‐renewal and multipotent properties, these cells can potentially provide an unlimited tissue source for neural grafting in neurodegenerative disorders. However, the capability of neurons derived from these stem cells to project axons to distant targets following grafting, thereby enabling the restoration of damaged CNS circuitry, remains unknown. We hypothesize that grafted EGF‐responsive stem cells and their progeny are not competent to project axons into distant target sites unless exposed to specific neurotrophic factors. We compared neurite outgrowth between gestation day 14 primary mouse hippocampal cells and EGF‐generated secondary neurospheres of postnatal mouse hippocampal stem cells, following grafting onto the CA3 region of organotypic hippocampal slice cultures prepared from postnatal rats. Neurite outgrowth from grafted cells was visualized using immunohistochemical staining for the mouse specific antigen M6. Fetal hippocampal cells showed extensive and specific neurite outgrowth into many regions of the slice, including the CA1 region and distant subiculum, by 7 days after grafting. In contrast, neurite outgrowth from neurosphere cells was nonspecific and restricted to the immediate surrounding region after either 7 or even 15 days following grafting. Application of brain‐derived neurotrophic factor (BDNF) (5 ng in 0.5 μL) to slices on day 1 after grafting significantly enhanced neurite outgrowth from neurosphere cells, but overall neurite outgrowth from neurosphere cells remained decreased compared to that from fetal hippocampal cells. These results underscore that EGF‐responsive stem cell‐derived neurons possess limited intrinsic capability for long‐distance neurite outgrowth compared to fetal neurons. However, neurite outgrowth from EGF‐responsive stem cell–derived neurons can be enhanced by treating with specific neurotrophic factors such as BDNF. © 1999 John Wiley & Sons, Inc. J Neurobiol 38: 391–413, 1999     

Treatment of low strength complex wastewater using an anaerobic baffled reactor (ABR)

Treatment of a low strength complex wastewater of chemical oxygen demand (COD) around 500mg/L was studied in a 10L capacity laboratory scale anaerobic baffled reactor (ABR). It was operated at hydraulic retention times (HRTs) of 20, 15, 10, 8 and 6h. Corresponding organic loading rates (OLRs) were 0.6, 0.8, 1.2, 1.5 and 2kg COD/m(3)d. At every HRT (or OLR), pseudo steady state (PSS) was achieved. Even at maximum OLR of 2kg COD/m(3)d, COD and biochemical oxygen demand (BOD) removals exceeded 88%. Removal of particulate fraction of organics was found to be greater than soluble fraction. Compartment-wise studies of various parameters revealed that if the OLR was larger, the number of initial compartments played significant role in the removal of organics. The values of volatile fatty acids (VFA) demonstrated that hydrolysis and acidogenesis were the main biochemical activities in the initial few compartments. Based on the tracer studies, dead space in the ABR was found to range from 23% to 34%. The flow pattern in the ABR was classified as intermediate between plug flow and perfectly mixed flows. Observations from scanning electron micrographs (SEM) also suggested that distinct phase separation takes place in an ABR. Study of organic and hydraulic shock loads revealed that ABR was capable of sustaining the type of shock loads generally experienced at a sewage treatment plant (STP).     

Secretion of a platelet-derived growth factor homologue by rat alveolar macrophages exposed to particulates in vitro

Lung macrophages secrete a homologue of platelet-derived growth factor (PDGF) which induces the proliferation of fibroblasts in vitro. In previous studies, we showed that such a PDGF homologue is produced by rat alveolar macrophages and that rat lung fibroblasts have specific receptors for the macrophage-derived PDGF. In this study, we demonstrate the biological and physicochemical properties of the growth factor, as well as the time-related production of this factor following macrophage activation in vitro by organic and inorganic particles. Alveolar macrophages (AMs) collected by saline lavage from the lungs of rats were cultured in serum-free Dulbecco's modified Eagle's medium (SF-DMEM) for varying periods of time up to 72 h. The SF-DMEM "conditioned" by the AMs was used to treat early passage rat lung fibroblasts (RLFs), which were rendered quiescent by culturing in 2% platelet-poor plasma (PPP). Alveolar macrophage conditioned media (AMCM) in the presence of PPP caused increases in the number of fibroblasts, the percent of labeled fibroblast nuclei and tritiated [3H]thymidine incorporation. AMCM alone caused no detectable changes in fibroblast growth rate. These results indicate that AMs release a "competence-like" growth factor. The AMs were left untreated or were exposed to opsonized zymosan, carbonyl iron spheres or chrysotile asbestos fibers. Macrophages attached to a plastic substrate spontaneously produced the factor, and subsequent addition of the organic and inorganic particles to the macrophage cultures significantly increased the fibroblast-stimulating activity of the AMCM. The growth factor was stable after concentration (100-fold), lyophilization and reconstitution.(ABSTRACT TRUNCATED AT 250 WORDS)     

Energy analysis of solar water heating systems in india

This analysis can be called energy accounting of solar water heating systems. Five types of solar water heating systems have been considered. With the help of material balance, energy content has been found in these systems. Yearly output of systems has been found by conducting transient simulations using hourly data of radiation and ambient temperature. Such analysis has been done separately for one representative city of each of six climatic zones of India. The energy payback for India ranges from 0.73 to 4.16 years for the thirty cases considered here.     

Identification, purification and characterization of laterosporulin, a novel bacteriocin produced by Brevibacillus sp. strain GI-9

Background

Bacteriocins are antimicrobial peptides that are produced by bacteria as a defense mechanism in complex environments. Identification and characterization of novel bacteriocins in novel strains of bacteria is one of the important fields in bacteriology.

Methodology/Findings

The strain GI-9 was identified as Brevibacillus sp. by 16 S rRNA gene sequence analysis. The bacteriocin produced by strain GI-9, namely, laterosporulin was purified from supernatant of the culture grown under optimal conditions using hydrophobic interaction chromatography and reverse-phase HPLC. The bacteriocin was active against a wide range of Gram-positive and Gram-negative bacteria. MALDI-TOF experiments determined the precise molecular mass of the peptide to be of 5.6 kDa and N-terminal sequencing of the thermo-stable peptide revealed low similarity with existing antimicrobial peptides. The putative open reading frame (ORF) encoding laterosporulin and its surrounding genomic region was fished out from the draft genome sequence of GI-9. Sequence analysis of the putative bacteriocin gene did not show significant similarity to any reported bacteriocin producing genes in database.

Conclusions

We have identified a bacteriocin producing strain GI-9, belonging to the genus Brevibacillus sp. Biochemical and genomic characterization of laterosporulin suggests it as a novel bacteriocin with broad spectrum antibacterial activity.     

Ragweed Subpollen Particles of Respirable Size Activate Human Dendritic Cells

Ragweed (Ambrosia artemisiifolia) pollen grains, which are generally considered too large to reach the lower respiratory tract, release subpollen particles (SPPs) of respirable size upon hydration. These SPPs contain allergenic proteins and functional NAD(P)H oxidases. In this study, we examined whether exposure to SPPs initiates the activation of human monocyte-derived dendritic cells (moDCs). We found that treatment with freshly isolated ragweed SPPs increased the intracellular levels of reactive oxygen species (ROS) in moDCs. Phagocytosis of SPPs by moDCs, as demonstrated by confocal laser-scanning microscopy, led to an up-regulation of the cell surface expression of CD40, CD80, CD86, and HLA-DQ and an increase in the production of IL-6, TNF-α, IL-8, and IL-10. Furthermore, SPP-treated moDCs had an increased capacity to stimulate the proliferation of naïve T cells. Co-culture of SPP-treated moDCs with allogeneic CD3⁺ pan-T cells resulted in increased secretion of IFN-γ and IL-17 by T cells of both allergic and non-allergic subjects, but induced the production of IL-4 exclusively from the T cells of allergic individuals. Addition of exogenous NADPH further increased, while heat-inactivation or pre-treatment with diphenyleneiodonium (DPI), an inhibitor of NADPH oxidases, strongly diminished, the ability of SPPs to induce phenotypic and functional changes in moDCs, indicating that these processes were mediated, at least partly, by the intrinsic NAD(P)H oxidase activity of SPPs. Collectively, our data suggest that inhaled ragweed SPPs are fully capable of activating dendritic cells (DCs) in the airways and SPPs'' NAD(P)H oxidase activity is involved in initiation of adaptive immune responses against innocuous pollen proteins.     

Reduction in Ultrasonic Vocalizations in Pups Born to Rapid Eye Movement Sleep Restricted Mothers in Rat Model

The effects of rapid eye movement sleep restriction (REMSR) in rats during late pregnancy were studied on the ultrasonic vocalizations (USVs) made by the pups. USVs are distress calls inaudible to human ears. Rapid eye movement (REM) sleep was restricted in one group of pregnant rats for 22 hours, starting from gestational day 14 to 20, using standard single platform method. The USVs of male pups were recorded after a brief isolation from their mother for two minutes on alternate post-natal days, from day one till weaning. The USVs were recorded using microphones and were analysed qualitatively and quantitatively using SASPro software. Control pups produced maximum vocalization on post-natal days 9 to 11. In comparison, the pups born to REMSR mothers showed not only a reduction in vocalization but also a delay in peak call making days. The experimental group showed variations in the types and characteristics of call types, and alteration in temporal profile. The blunting of distress call making response in these pups indicates that maternal sleep plays a role in regulating the neural development involved in vocalizations and possibly in shaping the emotional behaviour in neonates. It is suggested that the reduced ultrasonic vocalizations can be utilized as a reliable early marker for affective state in rat pups. Such impaired vocalization responses could provide an important lead in understanding mother-child bonding for an optimal cognitive development during post-partum life. This is the first report showing a potential link between maternal REM sleep deprivation and the vocalization in neonates and infants.