Follicular development in the volcano mouse (Neotomodon alstoni alstoni, Rodentia: Muridae) from birth to maturity: A morphological approach

The present study describes the morphology and ultrastructural features of postnatal follicular development in the volcano mouse ( Neotomodon alstoni alstoni ), an endemic Mexican rodent. By the first week of age, germ cells were organized in clusters within the ovigerous cords, and only 51.8% of them were associated with somatic cells. At the ultrastructural level, pairing chromosomes and cellular junctions between germ and pregranulosa cells, such as desmosomes, were observed. At this time, the zona pellucida could not be detected in the formed follicles. From 15 to 28 days postpartum, growing follicles were located at the medulla and inner cortex of the ovary, but most were atretic. The first preovulatory follicles were seen at 40 days. Likewise, corpora lutea were observed at this stage of development, which shows that the volcano mouse is a spontaneous ovulator. The follicular development of the volcano mouse shows strong similarities with that of the golden hamster, particularly during the first week. The morphological changes observed during postnatal follicular development of the volcano mouse follow the same general histological pattern as reported for other mammals, although the timing of these events is species-specific.     

Scanning electron microscopy of the subarachnoid space in the dog: evidence for a non-hematogenous origin of subarachnoid macrophages.

Injection of viable BCG into the subarachnoid space of immunized and non-immunized dogs produced a 10-fold increase in the populations of pial free cells. In immunized animals injected three days previously with BCG, stereoscopic SEM revealed that many pial cells had rounded up and were protruding into the subarachnoid space. With continued rounding these cells took on amoeboid characteristics, with shapes that suggested a capacity for cell movement. Internally, these pial cells possessed an increased volume of perinuclear cytoplasm and organelles. Reactive pial cells could be distinguished from macrophages of presumed hematogenous origin on the basis of their surface morphology. These findings suggested that pial cells had the ability to alter their normal structural and behavioral characteristics and to become macrophage-like under these conditions of secondary challenge by BCG.     

Milk composition in the northern brown bandicoot, Isoodon macrourus (Peramelidae, Marsupialia)

Milk samples were obtained at regular intervals throughout lactation from northern brown bandicoots, Isoodon macrourus, in captivity. Total concentration of milk solids was initially 7% (w/w) and increased linearly to 45% (w/w) by 55 days. Carbohydrate, lipid and protein concentrations increased from about 2% (w/w) to about 7-8% (w/w) at 30 days. Thereafter they diverged, with lipid increasing to between 25-30% (w/w) at 56 days, protein reaching maximal values of 10-15% (w/w) at just over 40 days and carbohydrate gradually declining to about 5% (w/w) at 56 days before a rapid fall to 1-2% (w/w) at the completion of lactation. The milk of the bandicoot exhibits a similar pattern of change during the course of lactation to that shown by other marsupials.     

The substrate specificity of yeast hexokinase: reaction with D-arabinose oxime

By chromatography, electrophoresis, n.m.r. spectroscopy, and spectrophotometric assay, it has been shown that D-arabinose oxime acts as a weak substrate for yeast hexokinase. The enzyme-catalysed phosphorylation of the oxime, which exists as a mixture of E (80%) and Z (20%) acyclic forms in solution at equilibrium, is proposed to proceed via the transient formation of a furanoid species. Weak substrate-activity was also observed with 4-deoxy-D-xylo-hexose, but not with 5-deoxy-D-xylo-hexose. The relation of these and previous results concerning the carbohydrate-substrate specificity of yeast hexokinase in solution to X-ray crystallographic studies is discussed.     

Survey of Interferon Production and Sensitivity in Human Cell Lines

Seven presumed diploid and 11 established cell lines were studied for their ability to produce free interferon in response to a standardized Newcastle disease virus challenge. Interferon production was evaluated in both serum-containing and serum-free medium. The ability of these cell lines to respond to the application of a standard interferon preparation by becoming resistant to virus was also examined. The diploid lines were distinctly more efficient producers of interferon than were the established lines. They also evidenced a greater requirement for serum to produce their maximum titers, but some were able to produce good titers in serum-free medium. The diploid lines were uniformly more sensitive to the application of exogenous interferon than were the established cell lines and attained greater degrees of virus resistance, but all lines tested displayed measurable sensitivity to interferon.     

A geographic distribution database of Mononychellus mites (Acari,Tetranychidae) on cassava (Manihot esculenta)

The genus Mononychellus is represented by 28 herbivorous mites. Some of them are notorious pests of cassava (Manihot esculenta Crantz), a primary food crop in the tropics. With the exception of Mononychellus tanajoa (Bondar), their geographic distribution is not widely known. This article therefore reports observational and specimen-based occurrence data of Mononychellus species associated with cassava. The dataset consists of 1,513 distribution records documented by the International Center for Tropical Agriculture (CIAT) between 1975 and 2012. The specimens are held at CIAT’s Arthropod Reference Collection (CIATARC). Most of the records are from the genus’ native range in South America and were documented between 1980 and 2000. Approximately 61% of the records belong to M. tanajoa, 25% to M. caribbeanae (McGregor), 10% to M. mcgregori (Flechtmann and Baker) and 2% to M. planki (McGregor). The complete dataset is available in Darwin Core Archive format via the Global Biodiversity Information Facility (GBIF).     

Emotion Recognition from Physiological Signals Using Parallel Stacked Autoencoders

Neurophysiology - The problem of recognition of emotions in humans is still open from a few aspects. In our study, we used a deep learning method named stacked autoencoder to classify regions of...     

RAF2 is a RuBisCO assembly factor in Arabidopsis thaliana

Ribulose‐1,5‐bisphosphate carboxylase/oxygenase (RuBisCO) catalyzes the reaction between gaseous carbon dioxide (CO₂) and ribulose‐1,5‐bisphosphate. Although it is one of the most studied enzymes, the assembly mechanisms of the large hexadecameric RuBisCO is still emerging. In bacteria and in the C4 plant Zea mays, a protein with distant homology to p terin‐4α‐c arbinolamine d ehydratase (PCD) has recently been shown to be involved in RuBisCO assembly. However, studies of the homologous PCD‐like protein (RAF2, RuBisCO assembly factor 2) in the C3 plant Arabidopsis thaliana (A. thaliana) have so far focused on its role in hormone and stress signaling. We investigated whether A. thalianaRAF2 is also involved in RuBisCO assembly. We localized RAF2 to the soluble chloroplast stroma and demonstrated that raf2 A. thaliana mutant plants display a severe pale green phenotype with reduced levels of stromal RuBisCO. We concluded that the RAF2 protein is probably involved in RuBisCO assembly in the C3 plant A. thaliana.