Histoplasmosis in Montreal During the Fall of 1963, with Observations on Erythema Multiforme

Although Montreal is in an endemic area, significant clinical histoplasmosis with systemic manifestations has been, until recently, infrequently diagnosed. However, since the autumn of 1963, 31 cases of clinically significant histoplasmosis have been seen by the authors. These were divided into two groups: (1) patients in whom the diagnosis was established on the basis of histological and/or cultural demonstration of the fungus; (2) patients in whom the diagnosis was based on a positive histoplasmin skin test, a complement fixation antibody titre of 1:32 or greater and compatible clinical and radiological findings. An additional group of 11 patients who presented with erythema multiforme was investigated and a heretofore unrecognized relationship between histoplasmosis and erythema multiforme was established.     

Right Internal Mammary Artery Implantation into Right Ventricular Myocardium for Revascularization of the Entire Heart: Experimental Data and Preliminary Report

The left internal mammary artery implant combined with epicardiectomy and free omental graft provides three extra-coronary sources of blood. This operation tested in dogs with 92% main-stem occlusion of three coronary arteries protected 75% of the animals. Applied clinically in over 100 patients, the operation resulted in 90% improvement. To obtain complete myocardial revascularization, the right internal mammary artery has been used as a fourth source of extra-coronary blood. In 57 animals, the right internal mammary arteries were implanted into the anterior walls of the right ventricle; in 80% this vessel formed anastomoses with the right coronary tree, and in 65% with the right and left coronary arteriolar systems. Six patients are described who underwent right internal mammary artery implantation; five of these in addition had the combined operation of left internal mammary artery implant, epicardiectomy and free omental graft. All patients had completely blocked right coronary arteries; in addition, five had advanced disease of the left coronary arterial tree.     

Formation and function of compression wood in gymnosperms

Westing, Arthur H. (Middlebury Coll., Vt.). 1965.Formation and function of compression wood in gymnosperms. Bot. Rev. 31: 381–480 A review with ca. 575 references. The world literature pertaining to the biology of compression wood (Rotholz; reaction wood) is evaluated critically. Compression wood is a geotropic reaction to an inertial force and is peculiar to the Coniferales, Ginkgoales, and Taxales. It is formed by the cambium (or cambial derivatives) of the lower side of inclined stems and branches, where it expandsin situ thereby tending to right the former and maintain (or restore) the inherent angle of the latter. Compression wood is stimulated to form by applications of indoleacetic acid, but under natural conditions is interpreted to result from an increased sensitization of cells on the lower side to an insignificantly changed level of endogenous auxin. A theoretical model of the perception (susception) mechanism is advanced. The mechanics of righting is discussed and the forces involved are estimated. Frequent reference is made to other geotropic phenomena of the higher plants, particularly to tension wood, the analogue of compression wood in the arborescent Dicotyledoneae. Much pertaining to the perception, formation, and function of compression wood remains to be elucidated     

Cerebrovascular Occlusive Disease—Experience with Panarteriography in 300 Consecutive Cases

Three hundred patients with cerebrovascular occlusive disease have had cerebral angiographic examination at the Veterans Administration Hospital, San Francisco, in the last five years. The present technique consists of preliminary visualization of the aortic arch and the major extracranial branches, followed by selective study of the subclavian and carotid arteries as necessary for evaluation of the intracranial circulation.Nine major complications occurred (an over-all incidence of 3 per cent). Two patients died after angiography and seven had major neurologic deficits persisting for more than 24 hours. Three of these patients had permanent damage, but four recovered completely.One-third of the patients had extracranial disease and one-third had intracranial disease. No significant lesion was found in the remainder. In the 212 patients with lesions, multiple lesions were common, the average number being three. Six patients had brain tumors and five had aneurysms.The mechanism of the stroke could be ascertained readily in most of the patients, but the extent of the disease and the resulting symptoms varied considerably. Several patients with occlusion of most of the cerebral vessels had minimal symptoms, while others had catastrophic symptoms but only minimal findings at arteriography.     

Establishment of a leukemic cell model for studying human pre-B to B cell differentiation

Reproducible models for examining early stages of human B cell differentiation are poorly developed. We now describe the establishment and characterization of a novel human leukemic cell line that recapitulates the pre-B to B cell stage of differentiation. This cell line, designated BLIN-1, was initially established in tissue culture medium containing low m.w. B cell growth factor, and consistently shows a dependency on this cytokine for optimal growth at low density. BLIN-1 cells have a 9p chromosomal abnormality, identical to the abnormality present in the leukemic blasts from the patient's original bone marrow aspirate. The immunologic phenotype of BLIN-1 is consistent with a cell arrested at the pre-B cell stage of development. Analysis of Ig gene rearrangement and Ig expression in a series of BLIN-1 subclones show that the cells spontaneously rearrange kappa light chain genes, leading to the differentiation of surface kappa-negative pre-B cells into surface kappa-positive B cells. The BLIN-1 cell line is, to our knowledge, the first defined human model for examining this critical developmental stage in human B cell ontogeny. As such, it offers a unique resource for examining variables influencing onset of kappa L chain gene rearrangement and expression.     

Membrane-delimited cell signaling complexes: Direct ion channel regulation by G Proteins

Summary Ion channels are signaling molecules and by them-selves perform no work. In this regard they are un like the usual membrane enzyme effectors for G proteins. The pathways of G protein receptor, G protein and ion channels are, therefore, purely infor mational in function. Because a single G protein may have several ion channels as effectors, the effects should be coordinated and this seems to be the case. Inhibition of Ca²⁺ current and stimulation of K⁺ currents would have a greater impact than either alone. Additional flexibility is provided by spontane ous noise in the complexes of G protein receptor, G protein, and ion channel. By having a non-zero setpoint, the range of control is extended and the responses become bi-directional.     

Effect of Agricultural Operations and Precipitation on Vertical Distribution of a Nuclear Polyhedrosis Virus in Soil

TheAnticarsia gemmatalisnuclear polyhedrosis virus (AgNPV) was released in two soybean plots in September, 1991; the soil in the plots was then sampled periodically through July, 1992, to determine the effects of normal agricultural soil manipulations and precipitation on vertical distribution of the polyhedral occlusion bodies (POBs). The amount of AgNPV increased at all depths down to 37.5–50 cm as long as there was virus-contaminated plant matter, even dead soybean refuse, above the soil surface. Agricultural operations (disking, harrowing, mowing, planting, cultivating) had no effect on the amount or vertical distribution of AgNPV in soil. After the crop refuse was disked into the soil in November, the amount of POBs began decreasing at all depths; these decreases continued over winter and at times appeared to be associated with precipitation. The POBs were no longer detected below 37.5 cm by April, 1992, or below 25 cm by July, 1992. However, in July there were still 274 POBs/g in the top 2.5 cm of soil. Thus, agricultural operations should not hinder contamination of soybean leaves by AgNPV from its soil reservoir.     

Prebiotic polymerization: Oxidative polymerization of 2,3-dimercapto-l-propanol on the surface of iron(III) hydroxide oxide

The oxidation of 2,3-dimercapto-l-propanol by ferric ions on the surface of iron(III) hydroxide oxide (Fe(OH)O) yielded polydisulfide oligomers. This polymerization occurred readily at low dithiol concentration under mild aqueous conditions. Polydisulfide polymers up to the 15-mer were synthesized from 1 mM dithiol in 5 ml water reacted with iron(III) hydroxide oxide (20 mg, 160 µ mole Fe) for 3 days under anaerobic conditions at 40 °C and pH 4. About 91% of the dithiol was converted to short soluble oligomers and 9% to insoluble larger oligomers that were isolated with the Fe (OH)O phase. Reactions carried out at the same ratio of dithiol to Fe(OH)O but at higher dithiol concentrations gave higher yields of the larger insoluble oligomers. The relationship of these results to prebiotic polymer synthesis is discussed.     

The goblet cavity matrix in the larval midgut of Hyalophora cecropia

The larval midgut of the silkmoth Hyalophora cecropia was examined using scanning electron microscopy. Goblet cells were observed to contain within their cavities a matrix plug. This matrix material was extruded onto the lumen side of the epithelium when the tissue was stretched. The rôle of this matrix material in maintenance of the capacity of the midgut to transport ions in vivo and in vitro is discussed.