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Five patients received overdoses of vincristine ranging from 3.5 to 32 mg. Neurotoxicity accounted for most of the complications observed. Peripheral neuropathies, cranial nerve palsies, paralytic ileus, atony of the bladder, hypertension, hypotension, seizures, inappropriate ADH secretion, and severe bone marrow depression were all encountered. Two patients died within 72 hours of the overdose. Another patient died of sepsis 22 days after the overdose. Two patients recovered and were discharged. The three patients who survived longer than a few days showed improvement in the vincristine-induced neuropathy, and the two long-term survivors had essentially complete recovery. It appears that if a patient can be supported through the critical period following an overdose, he can be expected to recover normal neurologic function.

Lenses with pseudo‐exfoliation (PE) were suspended in a solution of lanthanum, which was present partly in ionic form, partly as electron‐dense tracer particles in colloidal solution, dependent on pH and on the concentration of lanthanum, By electron microscopy the tracer particles were found in a narrow zone along the surface of the PE excrescences. Only a few of the smallest particles had penetrated into their most superficial layer. In the specimens treated with ionic lanthanum, the effect was an electron‐dense staining of the PE material within a 1–2 μm thick superficial layer. The PE fibrils as well as parts of the interfibrillar spaces were stained. These results indicate the presence of proteoglycans, and confirm the concept of an interfibrillar matrix which excludes other macromolecules and particles from penetrating into the material.

Structural stability of the extracellular matrix is primarily a consequence of fibrillar collagen and the extent of cross-linking. The relationship between collagen self-assembly, consequent fibrillar shape and mechanical properties remains unclear. Our laboratory developed a model system for the preparation of self-assembled type I collagen fibers with fibrillar substructure mimicking the hierarchical structures of tendon. The present study evaluates the effects of pH and temperature during self-assembly on fibrillar structure, and relates the structural effects of these treatments on the uniaxial tensile mechanical properties of self-assembled collagen fibers. Results of the analysis of fibril diameter distributions and mechanical properties of the fibers formed under the different incubation conditions indicate that fibril diameters grow via the lateral fusion of discrete approximately 4 nm subunits, and that fibril diameter correlates positively with the low strain modulus. Fibril diameter did not correlate with either the ultimate tensile strength or the high strain elastic modulus, which suggests that lateral aggregation and consequently fibril diameter influences mechanical properties during small strain mechanical deformation. We hypothesize that self-assembly is mediated by the formation of fibrillar subunits that laterally and linearly fuse resulting in fibrillar growth. Lateral fusion appears important in generating resistance to deformation at low strain, while linear fusion leading to longer fibrils appears important in the ultimate mechanical properties at high strain.

This paper interprets and criticizes some of the views presented in Sydney Shoemaker’s book, Physical Realization (Oxford University Press, 2007), on the topic of how mental properties are realized by physical properties, given that, on his view, human persons are not even token-identical with human bodies.