HIV-particles in spermatozoa of patients with AIDS and their transfer into the oocyte

By immunocytochemistry and in situ hybridization at the electron microscopy level, and by the PCR technique, we have shown that HIV-1 binds and enters normal sperm; that viral particles, their antigens, and nucleic acid are present in sperm from HIV-1 infected men; and that such sperm can transfer HIV-1 like particles to normal human oocytes. We also present evidence that a galactosylceramide-like compound is present on the sperm membrane and could function as an alternative receptor for HIV.     

Unusual pattern of bacterial ice nucleation gene evolution

Bacterial ice nucleation activity (INA+ phenotype) can be traced to the product of a single gene, ina. A remarkably sparse distribution of this phenotype within three bacterial genera indicates that the ina gene may have followed an unusual evolutionary path. Southern blot analyses, coupled with assays for ice-nucleating ability, revealed that within four bacterial species an ina gene is present in some strains but absent from others. Results of hybridization experiments using DNA fragments that flank the ina gene suggested that the genotypic dimorphism of ina may be anomalous. A phylogenetic analysis of 16S ribosomal RNA gene sequences from a total of 14 ina+ and ina- bacterial strains indicated that the ina+ bacteria are not monophyletic but instead phylogenetically interspersed among ina- bacteria. The relationships of ina+ bacteria inferred from ina sequence did not coincide with those inferred from the 16S data. These results suggest the possibility of horizontal transfer in the evolution of bacterial ina genes.      

Establishment of an albino sand rat (Psammomys obesus colony and comparison with the natural coloured animal

The lifespan and fertility of albino sand rats were found to be severely reduced in comparison with a laboratory colony of brown sand rats. The albinos were also much more susceptible to diabetes, as judged by their glucose tolerance. In fact, untreated albinos had a higher incidence of diabetic response than coloured sand rats fed a diabetogenic diet. The albino sand rats reproduced poorly because of a reduction in male fertility. Circulating testosterone levels and seminal vesicle weights were reduced in the albinos. It is speculated that the reduction in reproductive capacity is related to diabetes.     

Relationship between the golgi apparatus, gerl, and secretory granules in acinar cells of the rat exorbital lacrimal gland

The method of secretory granuleformation in the acinar cells of the rat exorbital lacrimal gland was studied by electron microscope morphological and cytochemical techniques. Immature secretory granules at the inner face of the Golgi apparatus were frequently attached to a narrow cisternal structure similar to GERL as described in neurons by Novikoff et al. (Novikoff, P. M., A. B. Novikoff, N. Quintana, and J.-J. Hauw. 1971. J. Cell Bio. 50:859-886). In the lacrimal gland. GERL was located adjacent to the inner Golgi saccule, or separated from it by a variable distance. Portions of GERL were often closely paralleled by modified cisternae of rough endoplasmic reticulum (RER), which lacked ribosomes on the surface adjacent to GERL. Diaminobenzidine reaction product of the secretory enzyme peroxidase was localized in the cisternae of the nuclear envelope, RER, peripheral Golgi vesicles, Golgi saccules, and immature and mature secretory granules. GERL was usually free of peroxidase reaction product or contained only a small amount. Thiamine pyrophosphatase reaction product was present in two to four inner Golgi saccules; occasionally, the innermost saccule was dilated and fenestrated, and contained less reaction product than the next adjacent saccule. Acid phosphatase (AcPase) reaction product was present in GERL, immature granules, and, rarely, in the innermost saccule, but not in the rest of the Golgi saccules. Thick sections of AcPase preparations viewed at 100 kV revealed that GERL consisted of cisternal, and fenestrated or tublular portions. The immature granules were attached to GERL by multiple connections to the tublular portions. These results suggest that, in the rat exorbital lacrimal gland, the Golgi saccules participate in the transport of secretory proteins, and that GERL is involved in the formation of secretory granules.     

Plant intentionality and the phenomenological framework of plant intelligence

This article aims to bridge phenomenology and the study of plant intelligence with the view to enriching both disciplines. Besides considering the world from the perspective of sessile organisms, it would be necessary, in keeping with the phenomenological framework, to rethink (1) the meaning of being-sessile and being-in-a-place; (2) the concepts of sentience and attention; (3) how aboveground and underground environments appear to plants; (4) the significance of modular development for our understanding of intelligence; and (5) the concept of communication within and between plants and plant tissues. What emerges from these discussions is the image of a mind embodied in plant life.     

Constant amplitude of postsynaptic responses for single presynaptic action potentials but not bursting input during growth of an identified neuromuscular junction in the lobster, Homarus americanus

As lobsters grow from early juveniles to adults their body size increases more than 20-fold, raising the question of how function is maintained during these ongoing changes in size. To address this question we studied the pyloric 1 (p1) muscle of the stomach of the lobster, Homarus americanus. The p1 muscle receives multiterminal innervation from one motor neuron, the lateral pyloric neuron of the stomatogastric ganglion. Staining with antibodies raised against synaptotagmin showed that as the muscle fibers increased in length, the spacing between the terminal innervation increased proportionally, so the number of synaptic contact regions/muscle fiber did not change. Muscle fibers were electrically coupled in both juveniles and adults. The amplitude of single intracellularly recorded excitatory junctional potentials evoked by motor nerve stimulation was the same in both juveniles and adults. Nonetheless, the peak depolarizations reached in response to ongoing pyloric rhythm activity or in response to high-frequency trains of stimuli similar to those produced during the pyloric rhythm were approximately twofold larger in juveniles than in adults. This suggests that homeostatic regulation of synaptic connections may operate at the level of the amplitude of the single synaptic potential rather than on the summed depolarization evoked during strong rhythmic activity.     

Radiographic joint damage in rheumatoid arthritis is associated with differences in cartilage turnover and can be predicted by serum biomarkers: an evaluation from 1 to 4 years after diagnosis

Introduction  

The objective of this study was to determine whether serum biomarkers for degradation and synthesis of the extracellular matrix of cartilage are associated with, and can predict, radiographic damage in patients with rheumatoid arthritis (RA).