Hand Mycetoma: The Mycetoma Research Centre Experience and Literature Review

Mycetoma is a devastating, neglected tropical disease characterised by extensive tissue involvement resulting in destruction, deformities and disabilities in the affected patients. The hand is commonly affected by mycetoma thus compromises its functionality and hinder the patient’s daily activities of living. In this communication, we report on 533 patients with hand mycetoma managed over a period of 24 years at the Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan. Eumycetoma was the commonest type of mycetoma (83.3%) encountered. Males were predominately affected (69.2%) with a sex ratio of 2.2:1. The majority of the patients (84%) were young adult below the age of 40 years old at presentation. The generality of patients (86.4%) were from the Sudan mycetoma belt. Children and adolescents (28.1%), farmers (18.2%) and workers (17.4%) were more frequently affected. The majority of patients (67.4%) had disease duration of less than 5 years at presentation. The study, did not document significant history of local trauma, familial tendency, concomitant medical diseases or other predisposing cause for mycetoma in this population. Pain (23.1%) was not a disease feature in this series and 52% of patients had past surgery for mycetoma and recurrence. The right hand was affected most (60.4%), and 64% of them had small lesion at presentation. Conventional x-ray was only helpful in patients with advanced disease and the MRI accurately determined the disease extension. Cytological smears, surgical biopsies histopathological examination and grains culture were the principal diagnostic tools for causative organisms’ identification. In the present series it was difficult to determine the treatment outcome due to high patients follow up dropout.     

Purification of β-xylosidase from Aspergillus tamarii using ground oats and a possible application on the fermented hydrolysate by Pichia stipitis

In this study we determined that Aspergillus tamarii Kita is able to utilize Avena sativa L. (oats) for the production of β-xylosidase under static or shaking conditions in submerged liquid-state (LSF), solid-state (SSF) and slurry-state (SlSF) cultures. The produced enzyme was purified and characterized. Maximum yield occurred under shaking conditions in SSF cultures (33.7 U/ml), with 24.9 and 5.5 U/ml produced in SISF and LSF cultures, respectively. Peptone was found to be the best nitrogen additive and enhanced enzyme production (41.5 U/ml). The produced enzyme was precipitated by ammonium sulfate (60 %) and further purified by gel filtration through a Sephadex G-100 and ion exchange column of diethylaminoethyl cellulose, with a yield of 40.57 % and 35.73-fold purification. Enzyme activity was optimal at pH 5.5 and 55 °C. The purified enzyme retained full activity even at the end of a 1-h incubation at this optimal condition. Midpoint of thermal inactivation (Tm) was recorded at 60 °C after 90 min of exposure. The Michaelis–Menten constant, maximal reaction velocity, turnover number and specificity constant of the purified enzyme were calculated to be 0.075 mg/ml, 71.42 U/mg of protein, 7.14/S and 95.2 mg/ml/s, respectively. The inability of the purified enzyme to hydrolyze celluloses indicated that the enzyme was a free cellulase. The most efficient enzyme activators were Mg2+, followed by Mn2+ and Zn2+ in that order. The molecular mass of the purified enzyme was 91 kDa as determined by SDS-PAGE. The possibility of using the fermentation of ground oat hydrolysate for the production of ethanol and xylitol in the presence of Pichia stipitis Pignal was assessed. The maximum production of ethanol and xylitol were obtained after 72 h of fermentation, resulting in 11.06 and 21.51 g/l respectively.     

Chromosome Segregation and Peptidoglycan Remodeling Are Coordinated at a Highly Stabilized Septal Pore to Maintain Bacterial Spore Development

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Comparison of exercise effects on the hemodynamics of the Bio 14.6 cardiomyopathic hamster.

1. Comparisons of the effects of 4 and 16 weeks of exercise were made on; cardiac output, stroke volume, heart rate, left intraventricular systolic and diastolic pressures, dP/dt, and heart calcium in the Bio 14.6 cardiomyopathic and F1 B hamsters. 2. In the cardiomyopathic hamster the cardiac output, stroke volume, left intraventricular systolic pressure and dP/dt, which were all depressed in the age related sedentary animals, were increased by both periods of exercise. The left intraventricular diastolic pressure which was elevated was likewise decreased by both exercise periods. Only the 16 week exercise period decreased the resting heart rate. 3. In the normal F1 B hamster, both periods of exercise increased the cardiac output and stroke volume while the left intraventricular systolic pressure was decreased. Only the 16 week exercise decreased the resting heart rate and left intraventricular diastolic pressure and increased the left ventricular dP/dt. 4. Both periods of exercise increased the total heart calcium in the Bio 14.6 hamster while the heart calcium in the F1 B was increased only by the 16 week exercise period.     

Bioefficacy of cadmium and lead on cotton leafworm Spodoptera littoralis (Lepidoptera: Noctuidae) larvae

The sensitivity of Spodoptera littoralis second and fourth instar larvae to the heavy metals cadmium (Cd) and lead (Pb) was investigated under laboratory conditions. Both Cd and Pb, even, at very low concentrations, had relatively high toxic effects on S. littoralis larvae. Cd was more toxic to S. littoralis larvae than Pb. In addition, the mean percentage feeding deterrence (FDI%) of Cd and Pb was concentration-dependent. The nutritional indices (consumption index, growth rate, efficiency of converted ingested and digested food, and approximate digestibility) of S. littoralis second and fourth instar larvae were more affected in Cd-treatments compared with those of Pb-treatments. Therefore, the presence of such heavy metals in the environment would exert an adverse impact on S. littoralis larvae and their development.