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By screening for mutants which could not degrade cellulose, several cellulase-less mutants were isolated from the wood-rotting fungus Polyporus adustus. Most of the mutants lacked mannanase and xylanase as well. In wild type, the level of cellulase, mannanase, and xylanase was higher when the fungus was grown in a medium containing cellulose than in a medium lacking cellulose. It is proposed that in P. adustus, the induction of this group of enzymes is under the control of a single common regulator gene.

When a toothpick or other wooden splinter is embedded in the soft tissues, chronic irritation occurs and secondary infection is commonplace. It is likely that both of these factors lead to the bone and soft tissue changes which result in so-called "pseudotumors" or "osteomyelitis-like lesions." Delay in diagnosis is not uncommon, for the history of foreign body embedment may be nebulous. However, when the roentgenographic findings of: (1) deep soft tissue thickening or swelling; (2) periosteal new bone reaction; on (3) osteolytic or osteoblastic bone change are seen in the presence of prolonged soft tissue infection, with or without a draining sinus, the diagnosis of such a chronically embedded foreign body should be strongly suspected. Surgical exploration and removal of the foreign body is mandatory, for if the foreign body is not removed, inflammation and infection do not resolve. If the foreign body is removed, complete clinical and roentgenographic resolution is the rule.

High rates of acetylene (C 2 H 2 ) reduction (nitrogenase activity) were observed in woodroom effluent from a neutral sulfite semi-chemical mill under aerobic (up to 644 nmol of C 2 H 4 produced per ml per h) and under anaerobic (up to 135 nmol of C 2 H 4 produced per ml per h) conditions. Pasteurized effluent developed C 2 H 2 reduction activity when incubated under anaerobic but not under aerobic conditions. Activities were increased by addition of 0.5 to 3.0% glucose or xylose. Enrichment and enumeration studies showed that N 2 -fixing Azotobacter and Klebsiella were abundant, and N 2 -fixing Bacillus was present. Of 129 isolates of Klebsiella from pulp mills, lakes, rivers, and drainage and sewage systems, 32% possessed nitrogen-fixing ability.

The commonest wood preservatives are the natural toxicants that are mainly responsible for the varying amounts of decay resistance in untreated heartwood. There are volatile materials in some woods that are effective against fungi and green plants while they last (Sowder, 1929; Weintraub and Price, 1948), as well as water-soluble materials that favor fungi (Findlay, 1956). It is true that the correlation between decay resistance and the amount and toxicity of extractable material has not been good even within the same species (Scheffer et al., 1944), but this is also true for extracts from preservative-treated wood. The tree is therefore logically the first biological variable to consider. The differences between the most important tree species both in their natural decay resistance and in their ability to absorb artificial preservatives are fairly well known as a result of practical experience. Analysis of the differences within species to determine the contributions to natural resistance of such factors as age and size of tree, position in tree, and genetic differences between trees has been made particularly in the classical statistical studies by Scheffer et al. (1949) and Scheffer and Hopp (1949) on locust and white oak. Correspondingly thorough studies on variation wvithin species in relation to treatability have not been encountered. For use in boats and ships, the natural preservatives in the wood have continued to be more important than artificial preservatives. It is true that most of the practical interest in industry is undoubtedly in the factors that influence success of artificial preserva

A numerical key for the identification of cultures of 126 species of wood-rotting fungi, with accompanying descriptions of the cultural characters of each species, is presented. The list of species includes many of the fungi most frequently encountered in studies of decay in various hosts, the species having been chosen without restriction as to host or locality. The descriptions and key have been based on cultural characters, both macroscopic and microscopic, that can be demonstrated readily without the aid of elaborate equipment or methods. Thus, cultures were grown in Petri dishes on Difco malt agar and on malt agar to which gallic or tannic acid had been added. They were incubated in the dark at room temperature and examined at weekly intervals for six weeks. Host relationships and physiological and morphological characters proved to be of diagnostic value. The physiological characters used in the key include the pigmentation of the mycelial mat, color changes induced in the agar by the fungus, rate of growth, and effect on media containing gallic or tannic acid. Morphological characters used in diagnosis were types and septation of hyphae, occurrence of secondary spores – chlamydospores, conidia, oidia – and of special structures, such as cystidia and setae, and the formation of fruit bodies. The numerical key will permit the interpolation of additional species as they are described and their code numbers prepared.

Respiratory disease resulting from prolonged exposure to wood dusts may be due to a hypersensitivity reaction in addition to the nonspecific toxic or irritant effects of the inhaled materials. In four patients the hypersensitivity response was manifested by two clinical patterns, one characterized by immediate onset and rapid reversibility of asthmatic symptoms, and the other by a more delayed onset and more gradual reversibility. In this disease the clinical history and challenge with the suspected offending dust proved to be of greater diagnostic importance than skin testing.

A study of the microbial ecology of copper–chrome–arsenic treated and untreated Pinus radiata and Eucalyptus regnans sapwood ground stakes exposed for a total of [Formula: see text] years is currently being made. The results presented in this report cover the initial colonization period during the first 7 months of exposure. Soft rot in the outer layers of both species of untreated wood occurs after only 1 month in the ground. Treatment with CCA prevents the early attack of pine but is not as effective in the eucalypt, nor does it appear to have a significant effect upon the diversity of microorganisms which colonize the two woods. For the first 2 months Penicillia are the predominating members of the population. Trichoderma viride, Paecilomyces fumo-roseus, and Cladosporium spp. are also frequently isolated. At 4 months more active soft-rotting fungi can be isolated, e.g. Chaetomium globosum and Humicola grisea, together with Fusaria and Phycomycetes. Bacteria colonize the stakes at a very early stage, the population changing little over this initial period of the study. Actinomycetes were not isolated until the wood had been in the ground for a month or more after which their importance in the population has steadily increased. Basidiomycetes were microscopically observed in sections of the stakes but have not been isolated to date.

Four fungi known to be active in the decomposition of wood and forest litter were grown on a liquid medium containing salts and glucose and also on aqueous extracts of a variety of fresh leaves and litter. The polysaccharides produced in the various culture media by the same organism were found, by chromatography of the hydrolyzates, to be of the same composition. In some cases, when the fungi were grown on leaf or litter extracts, polysaccharide synthesis did not take place because of lack of carbohydrate material. In many instances polysaccharide synthesis was inhibited by a factor or factors present even in much diluted extracts.

A technique is described for training ants in a T-maze, using olfactory cues. True olfactory learning occurs and amputation of the antennae prevents the use of olfactory cues. Amputation of one antenna causes a slight falling off in performance, but the ants still perform well above chance level after the operation. After ants have been trained in an olfactory discrimination, the effect of brain lesions on performance is studied. Severing the tracts between both antennal lobes and the alpha lobes of the mushroom bodies causes performance to fall back to chance level. Severing the tracts on only one side of the brain, or lesions placed elsewhere, does not disturb performance. Results are discussed in relation to the involvement of the mushroom bodies and antennal lobes in learning. (Author)

The characteristics of various types of D-T neutron generators are described and the current status of the development of fast neutron therapy machines is reviewed. For clinical applications a minimum average yield of 4 × 10 12 neutrons/sec is required. However, it is concluded that at present no 15 MeV neutron radiotherapy system can produce this output for a reasonable period of time, e.g. 50 hr. Further developments of all systems are urgently required. The properties of tritium targets are discussed with respect to the target life time and the radiation hazards. Experimental data are presented on the neutron yield as a function of the energy of the bombarding deuterons and target age. The tritium contents of the oil of the accelerator vacuum pumps and the tritium contents of the gas released at the exhaust opening of the rotary pump have been measured. It is concluded that only a small fraction of the total amount of tritium originally present in the target is expelled through the forepump exhaust. With regard to the shielding of 15 MeV neutrons, a summary has been given of experimental attenuation data for various materials.

Fractions from toxins adsorbed at charcoal have been separated by extraction. The acetone fraction causes decrease in the formation of reducing sugars and increase in sugar consumption, decrease in yield of 2,3 butanediol. The absolute alcohol fraction causes decrease in the formation of reducing sugar without affecting the sugar consumption and considerable decrease in the yield of 2,3 butanediol. The petroleum ether fraction increases the formation of reducing sugar without increasing the sugar consumption. It greatly decreases the production of 2,3 butanediol. All fractions inhibit formation of acetoin.

The predominant cellulolytic ruminal bacteria isolated from microbial populations supplied diets containing cellulose as an energy source and essentially devoid of amino acids or rapidly fermentable carbohydrates were shown to require branched-chain acid(s) for growth.

The numbers of yeasts in the effluent disposal system of the Prince Albert, Saskatchewan Pulp Mill occasionally reached 1 × 106 cells/liter, but were usually below 5 × 105 cells/liter. Rhodotorula species were commonly isolated and sometimes amounted to half of the population, though usually the relative numbers were considerably lower. The highest counts were found in late summer and early autumn. Bacterial counts varied from 20 × 106 to 74 × 106 cells/ml. Chemical O2 demand (COD) reached about 1200 mg/liter at times, and decreased as the effluent moved through the disposal system, about 40% of the total COD being removed during the treatment process. A considerably wider range of yeast species was found in the pulp mill disposal basins than in the Saskatoon sewage treatment plant. Most of the ascosporogenous yeasts found were Hansenula or Pichia species usually occurring in association with trees, as were many of the Candida species isolated.

—Cork particles and fungus spores were commonly airborne in a cork factory in Portugal where some workers suffered from suberosis. Where cork was being handled and shaped, fungus spores were usually more common than cork particles. In a warehouse (Junddo) where cork had moulded, up to 54 x 106 spores/m3 were general in the air, but workers handling the mouldy cork were exposed to as many as 128 x 10* spores/m*. Cork particles were most common close to cutting and sanding machines, but seldom exceeded 2x10* particles/m3 air. The most abundant species were Penicillium frequentans Westling, P. granulatum Bain., Aphanocladium album (Preuss) W. Gams, Monilia sitophila (Mont.) Sacc. and Mucor plumbeus Bon. P. frequentans was common everywhere in the factory and mostly in units small enough to penetrate into alveoli RESP-6856

Several kinds of nutrients were perfused to soil-inoculated veneers and were found not to change significantly the frequencies of microfungi isolation, but to have more effect on the rate of strength loss. Woods supplied with small amounts of nitrogen nutrient had slight strength reductions and thus indicated the adaptability of these microfungi to such conditions.The presence of nitrogenase activity within deteriorated wood was demonstrated and this suggested that over a long period of time nitrogen-fixing microorganisms might increase the wood nitrogen content.Amino compounds present in wood were altered with nitrous acid and shown not to upset the colonization patterns or the rate of decay. Some depolymerization of the cellulose fraction with further treatment by dilute alkali and ammonia gave varied results and no apparent decay when perfused with water.Leaching the wood with dilute acid gave a decrease in nitrogen content and this again did not affect the fungal growth, but it did prevent a loss of strength when perfused with water. It might provide a method of preserving timber used in certain conditions.

Volatile fatty acids (60% acetic and 40% propionic) were mixed into fresh pine sawdust at 1% and 3% (w./w.) levels. Unsexed day-old broiler chicks were placed on the litter at a density of 0.06 m.2 per bird and reared to 8 weeks of age. There was no significant effect among treatments on the mean body weight, feed conversion efficiency or mortality. The bacterial count was retarded for at least a week. The mold count was slightly decreased at the 3% treatment level for the first 2 weeks. The pH of the litter was reduced significantly (P

A fungus, Aspergillus fumigatus Fres., which used bark as its sole carbon and energy source, was isolated. Difficulties arose in measuring fungal growth, since the hyphae and the bark could not be separated. Measurement of the weight loss of the solid material did not quantitatively estimate fungal growth. Therefore, two methods were developed to estimate fungal mass when the carbon and energy source is particulate and contributes to the parameter used as a measure of growth. They were based on determination of nitrogen either in the solid material or in the medium. The nitrogen concentration in A. fumigatus was found to be nearly constant throughout the growth cycle and to be independent of the carbon and nitrogen concentrations in the medium but to vary with the carbon source used.Aspergillus fumigatus was grown at 37C as a submerged culture in salts medium with finely ground bark from Picea abies as sole carbon and energy source. The bark medium was heat-sterilized before inoculation with spores. The fungus utilized cellulose and hemicellulose but not lignin. Substances solubilized from the bark contributed to the growth. The yield was the same on unextracted as on water-extracted bark, although growth was delayed on the former. Growth was rapid and comparable to growth on other polymeric polysaccharides, i.e. starch. Aspergillus fumigatus degraded 32–40% of the polymeric part of the bark within 4 days and with an economic coefficient of about 50%.

The degradation of several alkyl ethers of vanillic acid, of 3-ethoxy-4-hydroxybenzoic acid, and of syringic acid, by the lignin-decomposing fungus Polyporus dichrous included (i) 4-dealkylation (e.g., 3-ethoxy-4-isopropoxybenzoic acid was in part dealkylated to 3-ethoxy-4-hydroxybenzoic acid), (ii) hydroxylation of the 4-alkoxyl groups (e.g., 3-ethoxy-4-isopropoxybenzoic acid was oxidized in part to 2-[4-carboxy-2-ethoxyphenoxy]-propane-1-ol), and (iii) reduction of carboxyl groups (older cultures) (e.g., 3-ethoxy-4-isopropoxybenzoic acid was reduced to 3-ethoxy-4-isopropoxybenzaldehyde and 3-ethoxy-4-isopropoxybenzyl alcohol). Some ethers (e.g., tri- O -methyl gallic acid and glycerol-β-[4-carboxy-2-ethoxyphenyl]-ether) were not affected. The dealkylations and hydroxylations indicate that the fungus has a relatively nonspecific mechanism for oxygenating various 4-alkoxyl groups of alkoxybenzoic acids; no evidence for oxygenation of 3-alkoxyl groups was obtained. Hydroxylation products were generally degraded further, probably via dealkylation. The vanillic acid and 3-ethoxy-4-hydroxybenzoic acid formed by dealkylations were readily metabolized. Although the isopropyl ether of syringic acid was hydroxylated to 2-(4-carboxy-2, 6-dimethoxyphenoxy)-propane-1-ol, neither this compound nor the parent isopropyl ether was dealkylated; syringic acid itself was only slowly and incompletely metabolized. The relationship of these results to lignin degradation is discussed.

ALLERGIC eczematous contact type dermatitis caused by cocobolo wood has been reported several times, but at infrequent intervals. We have reason to think that sensitization to this wood and clinical episodes from contact with it are commoner than the sparse reports would lead one to expect. Also, we will indicate a rather new source of exposure which we think may make dermatitis of this causation commoner still. The earliest record we could find of an eruption attributed to cocobolo wood came from abroad. Stern (cited by Levin 1 ) in 1891 reported cheilitis in flute players whose instruments had mouth pieces made of this material. In this country MacKee 2 was one of the first to note dermatitis from cocobolo wood. His case was occupational and occurred in a person who scraped the wood in the processing of it for handles and backs of hair brushes. Since then there

ONE OF THE rare causes of recurrent eczema of the hands and fingers is an allergic dermatitis due to wooden-handled objects. Dermatologists should be ever mindful of this infrequent causative factor in dealing with persistent or recurring vesicular eczemas of the hands. Three cases have been proved in the past five years by one of us (J. B. H.). After we had talked with three colleagues about this novel cause of eczema of the hands, each one discovered a similar case. The wood at fault was cocobolo wood. Cocobolo wood is a Central American timber of the genus Dalbergia. Included in this genus are over two hundred and fifty species of trees and scandent shrubs widely distributed in the tropical regions of the world. There are some fifteen species which yield timber noted for good technical qualities and richness of color and grain. There are at least seven species

Catalpalactone, C15H14O4, a new type of phthalide derivative has been isolated from the wood of Catalpa ovata G.DON and C.bignonioides WALT, and its structure has been determined to be represented by the formula (I).

SummaryCells from blood stains in absorbent and nonabsorbent materials like stainless steel, unpolished wood, cloth, glass, and paper, can be correctly sexed using fluorescent stains even after 90 days, during which the stains had been exposed to light, unfixed.

DERMATITIS venenata in its relation to the plant world comprises more than is fully appreciated unless one especially studies the subject. The plant world consists of weeds,1flowers, vegetables, fruits, and trees. All trees have a potential irritant in the bark, freshly cut wood, dried wood, sawdust, leaves,2or other parts. Most of the recent literature on dermatoses due to woods3emphasizes the importance of exotic or foreign woods, with less mention of native woods as a cause of allergic dermatitis. Recently a wood worker was disabled seven months with a generalized dermatitis venenata simulating lymphoblastoma. His trouble throughout was attributed to sawdust, but the usual tests and investigations failed to establish this causal relationship. He recovered, but resuming work with sawdust reproduced the dermatosis. This recurrence as well as the results of tests confirmed the etiologic diagnosis of dermatitis venenata due to sawdust derived

Poria weirii produced peroxidase in yields amounting to 35% of those obtained from the same weight of horseradish roots. The three isozymes detected were distinct from those of horseradish.