Intramolecular junctions in single-walled carbon nanotubes are potentially ideal structures for building robust, molecular-scale electronics but have only been studied theoretically at the atomic level. Scanning tunneling microscopy was used to determine the atomic structure and electronic properties of such junctions in single-walled nanotube samples. Metal-semiconductor junctions are found to...

The epithelial barrier is fundamental to the physiology of most metazoan organ systems. Occluding junctions, including vertebrate tight junctions and invertebrate septate junctions, contribute to the epithelial barrier function by restricting free diffusion of solutes through the paracellular route. The recent identification and characterization of claudins, which are tight junction-associated ...

BACKGROUND Cardiomyocyte transplantation is an innovative strategy for the treatment of heart failure after myocardial infarction. Cell junctions show diverse temporal polarization toward intercalated disks during postnatal development and exhibit altered distribution in diseased hearts. To elucidate the formation of cell junctions between grafted and host cardiomyocytes at the border zone of m...

The RecG helicase of Escherichia coli is necessary for efficient recombination and repair of DNA in vivo and has been shown to catalyse the unwinding of DNA junctions in vitro. Despite these findings, the precise role of RecG remains elusive. However, models have been proposed in which RecG promotes the resolution of linked duplexes by targeting three-strand junctions present at D-loops. One su...

In vitro cultured cells are connected by different membrane junctions which may serve as a matrix for the monolayer, but which may also enable intercellu­ lar communication. Some of these intercellular infor­ mation exchanges may be detected by ionic coupling between the cells through so-called “low-resistance junctions” . Gilula and cow orkers1, for instance, have shown that metabolic cooperat...

What appear to be true septate junctions by all techniques currently available for the cytological identification of intercellular junctions are part of a complex junction that interconnects the Sertoli cells of the canine testis. In the seminiferous epithelium, septate junctions are located basal to belts of tight junctions. In thin sections, septate junctions appear as double, parallel, trans...

Junctions between fiber cells of bovine lenses have been isolated in milligram quantities, without using detergents or proteases. The structure of the isolated junctions has been studied by thin-section, negative-stain, and freeze-fracture electron microscopy and by x-ray diffraction. The junctions are large and most often have an undulating surface topology as determined by thin sectioning and...

Lanthanum tracer and freeze-fracture electron microscope techniques were used to study junctional complexes between granulosa cells during the differentiation of the rabbit ovarian follicle. For convenience we refer to cells encompassing the oocyte, before antrum and gap junction formation, as follicle cells. After the appearance of an antrum and gap junctions we call the cells granulosa cells....

Recent studies indicate that the basolateral amygdala exhibits fast rhythmic oscillations during emotional arousal, but the neuronal mechanisms underlying this activity are not known. Similar oscillations in the cerebral cortex are generated by a network of parvalbumin (PV)-immunoreactive interneurons interconnected by chemical synapses and dendritic gap junctions. The present immunoelectron mi...

Epithelial cells cover the body (e.g. skin), cavities (e.g. stomach, uterus, bladder) and ducts (e.g. renal tubules, intestine) of multicellular organisms, and thus constitute the frontier between the individual and the external milieu. In areas that withstand strong mechanical or chemical stress (e.g. skin, esophagus, cornea, vagina) epithelia are stratified, whereas in the rest of the body, t...