Multi-drug resistance is a growing problem in the treatment of infectious diseases and the widespread use of broad-spectrum antibiotics has produced antibiotic resistance for many human bacterial pathogens. Advances in nanotechnology have opened new horizons in nanomedicine, allowing the synthesis of nanoparticles that can be assembled into complex architectures. Novel studies and technologies are devoted to understanding the mechanisms of disease for the design of new drugs, but unfortunately infectious diseases continue to be a major health burden worldwide. Since ancient times, silver was known for its anti-bacterial effects and for centuries it has been used for prevention and control of disparate infections. Currently nanotechnology and nanomaterials are fully integrated in common applications and objects that we use every day. In addition, the silver nanoparticles are attracting much interest because of their potent antibacterial activity. Many studies have also shown an important activity of silver nanoparticles against bacterial biofilms. This review aims to summarize the emerging efforts to address current challenges and solutions in the treatment of infectious diseases, particularly the use of nanosilver antimicrobials.

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Silver nanoparticles as potential antibacterial agents.

The atlas compiled by these editors is a commendable effort and welcome addition to the mycology textbook sector. Up until now, the publication of medical mycology textbooks has been sparse and those that have been published are either too detailed for a resident in training or practicing physician or do not provide sufficient photographs or illustrations of the main features of the mycotic organisms. As a lecturer in mycology for the dermatology residents at my local teaching hospital and program, there are 3 key objectives of my mycology lectures: (1) to provide some type of organizational approach to mycotic organisms, (2) to provide a concise clinical history, and (3) to provide as many photographs and illustrations of mycotic organisms as possible. This atlas provides an exemplary addition to my book collection on medical mycology textbooks and sources for illustrations of mycotic organisms. The electron photomicrographs, photoplates, and line drawings of

Atlas of Clinical Fungi

https://www.k-state.edu/fungi/Greeting/Publications_files/2005%20Studies%20in%20Mycology.pdf

Seeking the elusive function of the root-colonising dark septate endophytic fungi

The spectrum of dermatophytes isolated from skin lesions had changed in last 70 years Before the Second World War in Germany, Microsporum audouinii and Epidermophyton floccosum ranked the first, whereas Trichophyton rubrum is the most common dermatophyte since the fifties of last century, accounting for 80-90% of the strains, followed by T mentagrophytes This evolution is typical for Central and North Europe and it needs to be connected with the increase in the incidence of tinea pedis In contrast, in Southern Europe and in Arabic countries, zoophilic dermatophytes, such as Microsporum canis or Trichophyton verrucosum, are the most frequently isolated In Europe, especially in Mediterranean countries, the incidence of M canis infection has strongly increased during the recent years and this dermatophyte is now the most prevalent in tinea capitis in children An analysis of the frequency and distribution of tinea pedis in different occupations and leisure-time activities as well as the routes of infection are reported The spreading of this disease in most developed countries of the world represents a considerable economic problem, since it was accompanied by a parallel increase in the frequency of onychomycosis which implies, as tinea pedis, large financial charges In poor developing countries, mycoses appear endemically, primarily with children, and their treatment often fails because of the lack of efficient antifungals The particular epidemiological situations of dermatophytoses and the pathogenic spectrum of dermatophytes are examined at the example of numerous countries

Updates on the epidemiology of dermatophyte infections.

The fungal symbionts forming ectomycorrhizas, as well as their associated bacteria, benefit forest trees in a number of ways although the most important is enhancing soil nutrient mobilization and uptake This is reciprocated by the allocation of carbohydrates by the tree to the fungus through the root interface, making the relationship a mutualistic association Many field observations suggest that ectomycorrhizal fungi contribute to a number of key ecosystem functions such as carbon cycling, nutrient mobilization from soil organic matter, nutrient mobilization from soil minerals, and linking trees through common mycorrhizal networks Until now, it has been very difficult to study trees and their fungal associates in forest ecosystems and most of the work on ECM functioning has been done in laboratory or nursery conditions In this review with discuss the possibility of working at another scale, in forest settings Numerous new techniques are emerging that makes possible the in situ study of the functional diversity of ectomycorrhizal communities This approach should help to integrate developing research on the functional ecology of ectomycorrhizas and their associated bacteria with the potential implications of such research for managing the effects of climate change on forests (C) 2010 Elsevier Ltd All rights reserved

The role of ectomycorrhizal communities in forest ecosystem processes: new perspectives and emerging concepts.

A total of 123 isolates of 14 species of dermatophytes and yeasts were screened for the activity of five extracellular enzymes including elastase, keratinase, protease (gelatinase), lipase and phospholipase, by using solid media. The optimal production and activity of each enzyme was determined with regard to different pH and temperatures. Keratinase activity was high with all the tested fungi with exception of Malassezia furfur. Protease (gelatinase) was produced only by dermatophytes. Elastase was secreted by three dermatophytes viz. Microsporum gypseum, Trichophyton mentagrophytes var. mentagrophytes and T. verrucosum, whereas lipase and phospholipase were detected in all the species except T. violaceum.

Extracellular enzyme activities of dermatophytes and yeast isolates on solid media

Summary
• The extent to which water channel transport is responsible for the observed increases in root water flow of ectomycorrhizal plants is reported here.
• To examine the contribution of water channel transport to root hydraulic conductance, temperatures in the range 4–20°C and mercuric chloride (HgCl2) were used to study the kinetics of water transport in ectomycorrhizal and nonmycorrhizal roots of American elm (Ulmus americana) seedlings.
• Hydraulic conductance declined with decreasing temperatures in both mycorrhizal and nonmycorrhizal seedlings. However, hydraulic conductance and conductivity were higher in the mycorrhizal than the nonmycorrhizal roots at all temperatures studied. Mercuric chloride had a relatively greater impact on root hydraulic conductance in nonmycorrhizal than mycorrhizal roots and activation energy for root hydraulic conductance was significantly higher in mycorrhizal than nonmycorrhizal plants.
• The results suggest that ectomycorrhizal hyphae increase hydraulic conductance of roots by decreasing water flow resistance of the apoplast rather than by water channel-mediated transport. The high rates of hydraulic conductance at low root temperatures might be important to plants growing in cold soils and under other challenging environmental conditions that inhibit metabolism and limit water transport.

Ectomycorrhizas increase apoplastic water transport and root hydraulic conductivity in Ulmus americana seedlings

White spruce [Picea glauca (Moench) Voss] seedlings were inoculated with Hebeloma crustuliniforme and treated with 25 mM NaCl to examine the effects of salinized soil and mycorrhizae on root hydraulic conductance and growth Mycorrhizal seedlings had significantly greater shoot and root dry weights, number of lateral branches and chlorophyll content than non-mycorrhizal seedlings Salt treatment reduced seedling growth in both non-mycorrhizal and mycorrhizal seedlings However, needles of salt-treated mycorrhizal seedlings had several-fold higher needle chlorophyll content than that in non-mycorrhizal seedlings treated with salt Mycorrhizae increased N and P concentrations in seedlings Na levels in shoots and roots of salt-treated mycorrhizal seedlings were significantly lower and root hydraulic conductance was several-fold higher than in non-mycorrhizal seedlings A reduction of about 50% in root hydraulic conductance of mycorrhizal seedlings was observed after removal of the fungal hyphal sheath Transpiration and root respiration rates were reduced by salt treatments in both groups of seedlings compared with the controls, however, both transpiration and respiration rates of salt-treated mycorrhizal seedlings were as high as those in the non-mycorrhizal seedlings that had not been subjected to salt treatment The reduction of shoot Na uptake while increasing N and P absorption and maintaining high transpiration rates and root hydraulic conductance may be important resistance mechanisms in ectomycorrhizal plants growing in salinized soil

Colonization with Hebeloma crustuliniforme increases water conductance and limits shoot sodium uptake in white spruce ( Picea glauca ) seedlings

Four fungal species including two dermatophytes and two saprophytes were isolated from sewage sludge samples at Basrah (Iraq) they were tested for their degradative ability towards three types of keratin substrates (human hair, chicken feathers and wool). The rate of keratin degradation was expressed as weight loss over three weeks of incubation using a liquid culture medium. Human hair had the highest degradation rate by colonization of Chrysosporium pannicola and Microsporum gypseum at a rate of 62% and 4% respectively. Chicken feathers were highly degraded by Aspergillus flavus (32%) while wool degradation was highest by C. pannicola (45.5%) and Trichophyton mentagrophytes var. erinacei (38%). There was a significant difference (p < 0.00l) in keratin substrate degradation rates by the examined fungi. Keratinase activity was highest for C. pannicola and M. gypseum in the culture medium baited with human hair. Aspergillus flavus revealed the highest activity of this enzyme in cultures amended with chicken feathers while T. mentagrophytes var. erinacei showed highest keratinase activity in cultures with wool substrate. The amount of protein released into the culture medium varied among the tested fungi. The medium's alkalinity increased over incubation time from 6.5 to 7.8. Microscopic examination showed maceration of the keratin substrates by the fungi.

Degradation of keratin substrates by fungi isolated from sewage sludge.

Low soil temperatures, common during the growing season in northern forests, have the potential to impede plant growth. In this study, water uptake, water relations, and growth characteristics were examined in aspen (Populus tremuloides) and white spruce (Picea glauca) seedlings that were inoculated with ectomycorrhizal fungi and grown at 20°C daytime air temperatures and low soil temperatures of 4°C and 8°C. Mycorrhizal associations had little effect on root and shoot biomass at both soil temperatures. Root hydraulic conductance (Kr) was higher in both mycorrhizal plant species compared to nonmycorrhizal plants, but there was no soil temperature effect on Kr in either species. Mycorrhizae also increased shoot water potential (Ψw) in Populus tremuloides but had no effect on Ψw in Picea glauca. The increases in Kr and Ψw were not reflected by changes in stomatal conductance (gs) and transpiration rates (E), suggesting that the reduction of water flow in seedlings exposed to low soil temperature was not lik...

Tawfik M. Muhsin

Papers

Extracellular enzyme activities of dermatophytes and yeast isolates on solid media

Ectomycorrhizas increase apoplastic water transport and root hydraulic conductivity in Ulmus americana seedlings

Colonization with Hebeloma crustuliniforme increases water conductance and limits shoot sodium uptake in white spruce ( Picea glauca ) seedlings

Degradation of keratin substrates by fungi isolated from sewage sludge.

The effect of ectomycorrhizae on water relations in aspen (Populus tremuloides) and white spruce (Picea glauca) at low soil temperatures