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This work aims at exploring an antagonistic actinobacterial strain isolated from the roots of Ziziphus lotus in bioformulation processes and the biocontrol of Rhizoctonia solani damping-off of tomato seedlings. The strain Streptomyces caeruleatus ZL-2 was investigated for the principal in vitro biocontrol mechanisms and then formulated in three different biofungicides: wettable talcum powder (WTP), sodium alginate propagules (SAP) and clay sodium alginate propagules (CAP). Compared to a marketed control products (Serenade® and Acil 060FS®), the formulated biofungicides were investigated against the R. solani damping-off of tomato cv. Aïcha seedlings. The strain ZL-2 produced chitinases, cellulases, β-1,3-glucanases, cyanhydric acid and siderophores. It also showed strong antagonistic effect on the mycelial growth of R. solani. Bioautographic and HPLC analysis revealed the production of a single or several co-migrating antifungal compounds. The biofungicide WTP presented an attractive biocontrol effect by significantly reducing the disease severity index (DSI) compared to untreated seeds. No significant differences were obtained compared to the chemical treatment with Acil 060FS®. The viability of spores and biocontrol efficacy of the WTP were confirmed after 1-year storage. Strain ZL-2 has never been reported in the bioformulation of active biofungicides against Rhizoctonia solani damping-off and this work opens up very attractive prospects in the fields of biocontrol and crop improvement., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Schizophyllum commune is a wood-rotting filamentous fungus that secrets a homopolysaccharide called as schizophyllan. Schizophyllan has several applications such as enhanced oil recovery, pharmaceutical materials and an anti-cancer drug carrier. Biomass growth and schizophyllan production increase the viscosity of the cultivation medium, thus resulting in mass transfer limitation for the substrate. In this study, adding talc and aluminium oxide microparticles into the cultivation medium was studied to improve the fungal growth and morphology. The response surface methodology and one factor at a time were applied to find the effects of microparticles with different sizes and concentrations on the schizophyllan production. The optimum concentration and size of aluminium oxide microparticles were obtained as 20 g L -1 and < 30 µm, respectively. Aluminium oxide microparticles in shake flask culture caused to increase the schizophyllan production from 10 to 15 g L -1 and decrease the cultivation time from 10 to 7 days. The production yield also increased from 0.11 to 0.30 g of schizophyllan/g glucose. Bioreactor cultivation showed a twofold increase in schizophyllan production from 1.5 to 3 g L -1 . The results of this study suggested a significant increase in the production of schizophyllan using a low-cost "microparticle-enhanced cultivation" without any further optimization of the culture medium.

Phytase can be used in animal's diets to increase the absorption of several divalent ions, amino acids and proteins and to decrease the excessive phosphorus release in manure to prevent negative effects on the environment. This study aimed to enhance the current submerged fungal phytase productions with a novel fermentation technique by evaluating the effect of the various microparticles on Aspergillus ficuum phytase production. It was observed that microparticles prevented bulk fungal pellet growth, decreased average fungal pellet size and significantly increased phytase activity in the submerged fermentation. Microbial structure imaging results showed that the average fungal pellet radius decreased from 800 to 500 and 200 µm by addition of 15 g/L aluminum oxide and talcum, respectively, in shake-flask fermentation. Also, addition of 15 g/L of talcum and aluminum oxide increased phytase activity to 2.01 and 2.93 U/ml, respectively, compared to control (1.02 U/ml) in shake-flask fermentation. Additionally, phytase activity reached 6.49 U/ml within 96 h of fermentation with the addition of 15 g/L of talcum, whereas the maximum phytase activity was only 3.45 U/ml at 120 h of fermentation for the control in the 1-L working volume bioreactors. In conclusion, microparticles significantly increased fungal phytase activity and production yield compared to control fermentation.

A 76-year-old man presented clinically with coughing and shortness of breath and was diagnosed radiologically to have massive pleural effusion as a combined feature of yellow nail syndrome. A lung biopsy was taken and revealed histologically: chronic non-specific inflammation in the pleuropulmonary border, intrapleural edema with eightfold pleural thickening in comparison to normal, angiogenesis in both the nutritive and functional intrapleural blood vessels, no abnormalities of lymphatic vessels with normal topographical distribution as detected by immunohistochemistry for antibody D2-40, granulomatous chronic foreign body reaction as a consequence of pleural effusion therapy by talcum pleurodesis.The histopathological findings of chronic non-specific pleuritis with angiogenesis and increased permeability of blood vessels led to massive intrapleural edema with pleural effusion. Abnormalities of lymphatic vessels could not be confirmed. Considering the features of this disease, they are probably secondary to chronic r infectious or immunological inflammation or paraneoplastic complications with angiogenesis (in about 19%).

Objective: To study the power Doppler findings of septic arthritis and noninfectious synovitis in an animal model., Materials and Methods: The right knees of 10 rabbits were inoculated with an aqueous suspension of Staphylococcus aureus. The right knees of 5 rabbits were injected with talc suspension. The right knees of 5 rabbits were injected with saline. All 20 left knees were injected with saline. Serial power Doppler images were obtained using constant-imaging parameters. Images were reviewed by blinded observers who assessed for increased power Doppler signal., Results: All 10 knees inoculated with S. aureus developed septic arthritis. Each infected rabbit knee demonstrated increased signal on power Doppler on at least one examination, ranging from 1-6 days after inoculation. Only 23 of 45 examinations of infected knees were unequivocally positive by power Doppler on examinations performed 1 to 6 days after inoculation. No knee with talc synovitis demonstrated increased power Doppler signal. No control knee demonstrated increased power Doppler signal., Conclusion: Increased power Doppler signal may be seen with septic arthritis; however, its intensity and timing may vary from subject to subject. A normal power Doppler examination does not exclude septic arthritis.

Background and Aims: The treatment of recurrent malignant pleural effusions is known to be difficult and varies from observation in asymptomatic patients to pleurectomy with varying results. This prospective study presents the efficacy and the limits of iodized talc pleurodesis in patients with malignant and non-malignant recurrent pleural effusions., Methods: In a prospective trial talc pleurodesis was performed in 50 patients with recurrent pleural effusions (malignant effusions: n=36, non-malignant effusions: n=14). After insertion of a chest tube and complete re-expansion of the lung, 5 mg of talc and 3 mg of thymol iodine were installed with 0.5 ml of 1% xylocaine/kg body weight and 30 ml 0.9% saline solution. The chest tube was removed after an average time of 4 days and chest radiographs were performed 1 month after instillation to evaluate the efficacy of pleurodesis., Results: Successful therapy was achieved in 31 of 33 patients (94%) with malignant effusions within a follow-up period of 7 months. Three patients died within 1 month after therapy due to progressive malignant disease. The treatment was successful in all cases of non-malignant effusions and complications did not occur in either group., Conclusions: These results indicate that pleurodesis with iodized talcum slurry is a simple and inexpensive method with high efficacy in controlling malignant and non-malignant pleural effusions.

In August 1981, pediatric hospitals in Ho-Chi-Minh Ville (Saigon) began to report numerous cases of a haemorrhagic syndrome in infants. A collaborative study with a French epidemilogist began on September 24, 1981, with the aim of finding the cause of this "new" haemorrhagic disease. After having excluded the hypothesis of a viral or bacterial infection, a retrospective study, using questionnaires with 83 items, concerning products of hygiene and nutrition and living conditions, was undertaken. This epidemiological investigation showed this phenomenon was caused by an anticoagulant contained in talcum powder. Analysis of the talcum powders found warfarin; the concentrations ranged between 1.7% and 6.5%. This dramatic episode (741 cases with 177 deaths) ended when the contaminated talc was withdrawn from circulation. The hypothesis of accidental contamination or use of warfarin in lieu of a perfuming agent must be rejected. Accidental addition of a rat-killer seems highly improbable and the possibility of intentional and malevolent adulteration is now under study. An experimental study of hemostasis in two baboons was carried out, using dermal application of the contaminated talc powder. The intoxicated animal died on the 5th day with severe vitamin K deficiency. This accident together with the animal study, shows the transcutaneous uptake of the anticoagulant, which could be of considerable importance in toxicology and in pharmacokinetics.

T-2 toxin was given to rats in three ways: Subcutaneous or intracerebral injection of a solution in dimethyl sulfoxide (DMSO) and by implantation of toxin, adsorbed on talc, into various regions of diencephalon and brain stem. The latter method proved to be most effective. Within a few hours after administration of 10-20 micrograms toxin, the animals became restless, ataxic and dyspneic. These early symptoms were followed by depression and immobility. Prior to death, tachypnea and/or convulsions developed. The rats succumbed to implantation of toxin within 1 - 7 days; no fatalities occurred at later dates. Histologically, the toxin pellets caused necrosis a few days after implantation; at a later stage, the necrotic areas were surrounded by inflammatory infiltrates around small blood vessels. These morphological changes were limited to the application site and were insufficient to explain the lethal effect of intracerebral administration. After intracerebral injections of toxin solutions, the animals died within 24 h. No marked histological changes could be seen after such rapid fatalities.