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Biomedical subjects

M Karaman

Publications and source records attributed to M Karaman.

4 recordsLinked to original sources

Evaluation of pathological changes in broilers during chronic aflatoxin (50 and 100 ppb) and clinoptilolite exposure.

This study was conducted to evaluate the pathological changes in broilers fed a diet containing low-levels of aflatoxin (AF) and clinoptilolite (CLI) until 42 days of age. A total of 576 one-day-old Ross-308 type broiler chicks were treated with varying levels of AF and CLI (15 g kg(-1)). The gross and histopathological changes in the liver, kidneys, spleen, thymus and bursa of Fabricius were investigated and relative organ weights were calculated. Compared to controls, significant changes (P<0.05), such as slight to moderate hydropic degeneration and/or fatty change (8 cases of 10), bile-duct hyperplasia (7 of 10) and periportal fibrosis (5 of 10), were found in chicks fed 100 ppb AF-containing diet. No gross-pathological changes were observed in any treatments. The addition of CLI to the 100 ppb AF-containing diet significantly decreased the number of affected broilers and/or the severity of lesions (hydropic degeneration and bile-duct hyperplasia) in the livers (P<0.05). The addition of CLI to the AF-free diet did not produce any significant lesions compared with the controls.

Aflatoxins↗

Evaluation of the detoxifying effect of yeast glucomannan on aflatoxicosis in broilers as assessed by gross examination and histopathology.

We evaluated the efficacy of yeast glucomannan (Mycosorb), incorporated into the diet at 0.5 and 1 g/kg, in reducing the detrimental effects of 2 mg aflatoxin/kg diet on growing broiler chicks from 1 to 21 d of age. A total of 240 male broiler chicks (Ross-308) was divided into 6 treatment groups [Control, Aflatoxin (AF), Yeast glucomannan (YG; 0.5 g/kg), AF plus YG (0.5 g/kg), YG (1 g/kg), and AF plus YG (1 g/kg)]. Ten chicks from each of the 6 groups were slaughtered and pathological examinations were performed on the liver, bursa of Fabricius, thymus, spleen and kidney. The aflatoxin treatment caused moderate to severe hydropic/fatty degeneration in the hepatocytes of the liver and the tubular epithelium of the kidneys, and follicular depletion in the bursa of Fabricius, thymus and spleen. Yeast glucomannan added to the aflatoxin-containing diet at 0.5 and 1 g/kg diminished the severity of pathological changes, slightly and moderately, respectively. The number of affected organs was also reduced in the group given 1 g/kg yeast glucomannan, compared to the aflatoxin group. These results show that yeast glucomannan effectively diminished the adverse effects of aflatoxin on the pathological changes and that the higher concentration of yeast glucomannan (1 g/kg) was more effective than the lower concentration (0.5 g/kg) and itself had no adverse effect.

Aflatoxins↗

Vancomycin-resistant enterococci in neonates.

Fecal-oral transmission of vancomycin-resistant strains of Enterococci (VRE), which colonize the human gastrointestinal tract, has led to nosocomial epidemics in recent years. The aim of this study was to establish the incidence and associated factors of fecal colonization with VRE in neonates. In our hospital 110 rectal swab specimens collected in the neonatal intensive care unit (NICU) were examined for VRE. For comparison, rectal swabs collected from 42 healthy neonates on the obstetrics ward were also analyzed. Of the NICU patients, 8 had VRE MICs of 8-64 microg/ml for vancomycin and 2-32 microg/ml for teicoplanin, whereas none of the healthy newborns, had VRE (p < 0.05). All patients positive for VRE had factors known to be associated with VRE carriage, such as low birth weight or long-term antibiotic therapy.

Cross Infection↗

Digital phased array beamforming using single-bit delta-sigma conversion with non-uniform oversampling.

Digital beamforming based on oversampled delta-sigma (delta sigma) analog-to-digital (A/D) conversion can reduce the overall cost, size, and power consumption of phased array front-end processing. The signal resampling involved in dynamic delta sigma beamforming, however, disrupts synchronization between the modulators and demodulator, causing significant degradation in the signal-to-noise ratio. As a solution to this, we have explored a new digital beamforming approach based on non-uniform oversampling delta sigma A/D conversion. Using this approach, the echo signals received by the transducer array are sampled at time instants determined by the beamforming timing and then digitized by single-bit delta sigma A/D conversion prior to the coherent beam summation. The timing information involves a non-uniform sampling scheme employing different clocks at each array channel. The delta sigma coded beamsums obtained by adding the delayed 1-bit coded RF echo signals are then processed through a decimation filter to produce final beamforming outputs. The performance and validity of the proposed beamforming approach are assessed by means of emulations using experimental raw RF data.

Journal Article↗