Studies on cellulases of some cellulose-degrading soil fungi.

In this study, novel cellulolytic fungal strains were isolated, purified, and identified. The ability of these isolates to biodegrade cellulosic materials was examined. The potential of the isolates to produce cellulolytic enzymes and optimize the cellulose degradation process was also investigated. The nylon net bag technique was used to separate cellulose-degrading fungi from soil. A total of 37 species were isolated and tested for their capacity to break down rice straw as a cellulose source. Qualitative assays for cellulase were carried out by Congo red plate assay, while quantitative assays were carried out using the dinitrosalicylic acid (DNS) method at 546 nm. Following morphological and molecular identification, the isolates that exhibited the highest cellulase activities were identified as Neurospora intermedia (Assiut University Mycological Center (AUMC) 14359), Fusarium verticillioides (AUMC 14360), and Rhizopus oryzae (AUMC 14361). For N. intermedia, the optimal conditions for maximum activity were a 2% carboxymethylcellulose (CMC) concentration, beef extract and peptone as nitrogen sources, pH 7, 30 °C, and an inoculum size of 2.5 (v/v). For F. verticillioides, the optimal conditions were 2.5% CMC concentration, yeast extract as a nitrogen source, pH 6, 30 °C, and an inoculum size of 2 (v/v). For R. oryzae, the optimal conditions were 2% CMC concentration, beef extract as a nitrogen source, pH 7, 30 °C and an inoculum size of 2.5 (v/v). The identified strains represent new starter strains with high efficiency under optimum conditions for prospective large-scale application in cellulose degradation and nanocellulose production-dependent water purification.

Computational studies of 2-(4-oxo-3-phenylthiazolidin-2-ylidene)malononitrile.

The molecular structure of the 2-(4-oxo-3-phenylthiazolidin-2-ylidene) malononitrile (3) is calculated using DFT B3LYP/6-311G(d, p) method. The calculated geometric parameters are in good agreement with the experimental data. The NBO calculations were performed to predict the natural atomic charges at the different atomic sites and study the different intramolecular charge transfer (ICT) interactions occurring in the studied system. The BD(2)C17-C19 → BD*(2)C14-C15, LP(2)O2 → BD*(1)N5-C9 and LP(1)N5 → BD*(2)C10-C11 ICT interactions causing stabilization of the system by 23.30, 30.63 and 52.48 kcal/mol, respectively. The two intense electronic transition bands observed experimentally at 249 nm and 296 nm are predicted using the TD-DFT calculations at 237.9 nm (f = 0.1618) and 276.4 nm (f = 0.3408), respectively. These electronic transitions are due to H-3 → L (94%) and H → L (95%) excitations, respectively.

Formulation of microemulsion gel systems for transdermal delivery of celecoxib: In vitro permeation, anti-inflammatory activity and skin irritation tests.

The aim of this study was to develop suitable microemulsion gel systems for transdermal delivery that could assist dissolution enhancement of poorly water soluble celecoxib and thus improve its skin permeability. Long term oral administration of celecoxib causes serious gastrointestinal adverse effects, which makes it a good candidate for transdermal formulations, yet its low water solubility (4 mg/L) makes this challenging. Ternary phase diagrams were constructed using isopropyl myristate and oleic acid as oils, Tween 80 as surfactant, and Cremophor RH40 as cosurfactant. Microemulsion areas were identified and two systems each of 36 formulas were prepared and assessed for visual inspection, spreadability, pH measurements, and droplet size analysis. Drug release and in vitro permeation of celecoxib from microemulsion formulas through semi-permeable membranes and excised abdominal rabbit skin, respectively, were carried out and compared to celecoxib cream. In all tested formulas, celecoxib was released and permeation was at a higher rate than that from the corresponding cream. The optimized formula (F12) was found to be superior to all other formulas. This formula increased the permeation rate of celecoxib up to 11 times compared to that of the cream. Its stability was retained after one year of storage under ambient conditions and its anti-inflammatory effect was significantly higher than that of celecoxib cream and the oral commercial formula. Skin irritancy and histopathological investigation of rat skin revealed its safety. The results revealed that the developed microemulsion gel has great potential for transdermal delivery of celecoxib.

Impact of repeated pesticide applications on the binding and release of methyl 14C-monocrotophos and U-ring labelled 14C-carbaryl to soil matrices under field conditions.

The dissipation of (O-methyl-14C) monocrotophos and U-ring labelled 14C-carbaryl was monitored for over two years in absence and presence of other insecticides using in situ soil columns. The dissipation of 14C-monocrotophos from soil treated with methomyl and carbaryl showed a faster rate of downward movement than in a control column tagged with the labelled insecticide alone. The same trend was observed in experiments with 14C-carbaryl that dissipated more readily in soil treated with non-labelled monocrotophos and methomyl. In the presence of other insecticides the percentage of bound residues was generally lower than in control experiments. The bound residues at the top of the column are released at a low rate under conditions prevailing in the field. The overall time required for dissipation of 50% of monocrotophos and carbaryl (t50) as estimated from control experiment was approximately 20 and 24 weeks, respectively. The data indicate that repeated applications of pesticides might enhance the release of 14C-bound residues.

Agronomic aspects and environmental impact of reusing marginal water in irrigation: a case study from Egypt.

Egypt produces approximately 2.4 million m3 of secondary treated wastewater (TWW) annually, used for irrigation directly or indirectly by blending with agricultural drainage water (BDW). The annual re-use of (BDW) is approximately 4 million m3. The safe and efficient use of marginal water (BDW and TWW) is a core objective of this study which has been operating from 1997 to date. After six growing seasons the main results can be summarized as follows: MAXIMIZING CROP PRODUCTION: TWW can be used for high production of oil crops (canola, soybean sunflower or maize) compared to fresh water, while BDW can be used for high production of tolerant crops (cotton and sugar beet). CROP QUALITY: using marginal water increases the concentration of elements (Pb, B, Ni, Co) in all crops but these elements were under critical levels (there were no toxicity hazards). It is better to use alternative irrigation with fresh water under a drip irrigation system to maximise crop production and minimise the adverse effects of such water in field crops quality. SOIL POLLUTION AND SALINITY BUILD UP: A drip irrigation system under alternative irrigation by fresh with TWW or BDW reduces salinity build up risks and the levels of elements (Pb, B, Ni, Co) in soil compared to re-use marginal water. SOIL PATHOGENS: Using marginal water slightly contaminated the soil with total faecal coliform (TFC), mites, shigella and salmonella. PLANT ANATOMY: No great changes in anatomical disturbance where induced in different structures of plants which were reduced at maturity stage. PRIMARY GUIDELINES FOR RE-USING MARGINAL WATER: From obtained results it can be recommended to use marginal water with salinity content ranged between 1.1 to 3.64dS/m, and elemental contents (Pb 3.0-3.51 ppm), (B 0.05-1.67 ppm), (Co 0.04-0.07 ppm), (Ni 0.08-0.15 ppm) for safe (field, vegetable and medicinal) crops production. REUSE BIO SOLIDS FOR CROP PRODUCTION: Sewage sludge produced from treated wastewater can be safely used by mixing with rice straw (1:1 w/w) for economic crop production and saving mineral fertilisers. GENERAL CONCLUSION: In the North Nile Delta, marginal water (especially BDW) can be safely used without significant negative impact on the environment, but there is a need for multi-disciplinary, long-term research to investigate irrigation with marginal water in terms of the environment, public health and agricultural productivity.

Urothelial ingrowth over demucosalized gastrocystoplasty: an experimental study.

OBJECTIVE: To evaluate histopathologically the ingrowth of urothelium over a demucosalized gastric flap used for augmentation, as such flaps increase the capacity of the bladder if the urothelium can cover the seromuscular patch. MATERIALS AND METHODS: The study included eight male dogs; the urinary bladder was widely divided at its dome anteroposteriorly to receive a seromuscular gastric flap, sutured to the edges of the urinary bladder. Before and 1 month after surgery the changes in bladder capacity and pressure were recorded, and urothelial ingrowth assessed histopathologically. RESULTS: Two of the eight dogs died; the increase in mean bladder capacity in the remaining dogs was 20% and the decrease in mean intravesical pressure 34%. Gross pathological examination of the urinary bladder showed good 'take' of the gastric flap by the urinary bladder. Histopathologically, there was good healing of the flap, active ingrowth of urothelium, and no mucosal re-growth. CONCLUSION: Bladder augmentation with a demucosalized gastrocystoplasty allows the creation of a large compliant urinary bladder with few complications caused by the incorporation of the enteric or gastric epithelium into the urinary bladder. The stomach has a rich blood supply, allowing the harvesting of a well-vascularized flap, and urothelial ingrowth over this flap in the present study was significant.

Dietary cancer risk from conditional cancerogens (tumor promoters) in produce of livestock fed on species of spurge (Euphorbiaceae). V. Skin irriitant and tumor-promoting diterpene ester toxins of the tigliane and ingenane type in the herbs Euphorbia nubica and Euphorbia helioscopia contaminating fodder of livestock.

Irritant diterpene ester toxins were isolated from Euphorbia nubica and E. helioscopia, which are contaminants of the green fodder of livestock in Egypt. Fractionations of methanol extracts of aerial parts of both plants were monitored by the irritation unit on the mouse ear. Plant extracts were subjected to multiplicative distribution methods, yielding irritant hydrophilic fractions that were further purified by column chromatography. Final purification of the materials was achieved by TLC (silica gel) followed by HPLC, or by TLC alone. In this way, from E. nubica, five Euphorbia factors (Nu1-Nu5) were isolated and characterized as short-chain polyfunctional diterpene esters of tigliane-type parent alcohols. The two weak irritants Nul and Nu3 were triesters of 4-deoxy(4alpha)phorbol. Nu2 was shown to be a triester of the stereoisomeric tigliane-type parent alcohol 4-deoxyphorbol. Weak irritant Nu4 probably is a positional isomer of Nu2. Nu5 was characterized as a short-chain triester of 4,20-dideoxy-5xi-hydroxyphorbol. From E. helioscopia, six short- to medium-chain polyfunctional diterpene esters of the ingenane type, generally containing unsaturated acids were obtained, i.e., four irritant esters of ingenol (Euphorbia factors H1, H2, H5, and H6) and two esters of 20-deoxyingenol (non-irritant Euphorbia substance HS4, and irritant Euphorbia factor H8). All irritant Euphorbia factors of the tigliane and ingenane diterpene ester type described in this investigation are considered to be more or less active tumor promoters, i.e., conditional (non-genotoxic) cancerogens. The Euphorbia factors assayed exhibited moderate (H1) to low (H8) relative tumor-promoting potency in comparison to the ingenane prototype DTE tumor promoter 3-TI.

Lindane degradation and effects on soil microbial activity.

The degradation of U-14C-lindane in two Egyptian soils was determined in a three-month laboratory incubation. Lindane mineralization was slow and limited in both soils. Evolution of 14CO2 increased with time but only reached 3.5 to 5.5% of the initial 14C-concentration within 90 days. At that time both soils contained about 88% of the applied radiocarbon; 33% to 37% of the initial dose was unextractable and assumed bound to the soils. The methanol-extractable 14C primarily contained lindane with traces of minor metabolites. Radiorespirometry was used to evaluate the effect of lindane on soil microbial activity. Low concentrations of the insecticide initially supressed 14CO2 evolution from U-14C-glucose and microbial activity was significantly inhibited by 10 mg lindane/kg soil.

Triple suspension rectopexy for complete rectal prolapse.

Twenty-eight patients with complete rectal prolapse were treated by a three-level triple suspension abdominal rectopexy with no recurrence and with improvement of rectal function. Rectal suspension was effected by three steel wire slings.

Middle latency auditory evoked potentials in temporal lobe disorders.

Middle latency auditory evoked potentials (MAEP) were recorded in 30 normal subjects and in 19 age-matched patients with temporal lobe lesions. MAEP appeared to be differentially affected by the specific structures involved within the temporal lobe. In the majority of patients with lesions involving the auditory area and/or auditory radiation, Na-Pa amplitude was significantly reduced over the involved hemisphere. No similar reduction in amplitude was noted in subjects with lesions not involving the auditory structures within the temporal lobe. We also observed a shift in a Pa latency over the involved hemisphere in patients with temporal lobe lesions involving the auditory structures. This latency shift was less pronounced than the amplitude reduction. The generators of MAEP in humans are discussed according to these findings and to the available literature. Normal intersubject variability of the conventional amplitude measures, and the occasional myogenic contamination of the response, limits establishing reliable criteria for abnormality that can be applied clinically for the diagnosis of patients with temporal lobe disorders.

Anchorage overlapping repair of incisional hernia.

Fifty-five incisional hernias at different sites were repaired by fashioning strips of the hernial sac with its entire coverings of collagen scar at one side. The strips are reversed through holes made in the superficial overlapping muscular layer and fixed back to the ipsilateral side. There were no major recurrences over a 2-10-year period except for a minor one at the upper end of a vertical repair. The operation was likewise performed with success in 28 patients with para-umbilical hernias. This triple layer anchorage technique is practically and theoretically sound since recurrences due to sliding of layers of simple overlapping repair with stitches cutting out do not occur.

Thyroid cartilage at the suprasternal notch with low situated thyroid gland.

The thyroid cartilage and thyroid gland forming a lump at the suprasternal notch is a surprising congenital anomaly which I believe has not been previously reported. A case with co-existent low hyoid bone, pharyngo-oesophageal junction and intrathoracic cricoid cartilage with no cervical trachea is presented. Its pathogenesis is suggested and its surgical importance is discussed.

Low-frequency sensorineural hearing loss: a syndrome.

Eleven patients were found to have a pattern of bilateral, predominantly low-frequency sensorineural hearing loss and disproportionate speech discrimination scores. These patients were submitted to pure-tone audiometry, Arabic speech audiometry, immittance, auditory brainstem response, middle-latency response, Arabic central auditory tests, EEG and computerised tomographic (CT) scan. Results pointed to a lesion in the central auditory pathway. Two possible etiological factors were considered: infection and epilepsy of the temporal lobe. This disease pattern should raise the audiologist-otologist's index of suspicion necessary for its identification and planning of further investigations. This will help determine the etiology and true nature of the syndrome.