This study assessed the toxicity of melamine against the unicellular eukaryotic system of Tetrahymena (T.) pyriformis exposed to 0, 0.05, 0.25, 0.5, 2.5, and 5 mg/mL of melamine. Cell growth curves of different cultures, the half maximum inhibition concentration (IC50) value of melamine, and morphological changes in cells were obtained via optical and transmission electron microscopic observation. The effects of eleven melamine concentrations, 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5 and 5 mg/mL, on protein expression levels of T. pyriformis were examined using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The results showed an obvious inhibitory effect of melamine on the growth of eukaryotic cells. Cell growth dynamics indicated that the IC50 value of melamine on T. pyriformis was 0.82 mg/mL. The cellular morphology was also affected in a concentration-dependent manner, with characteristics of atrophy or cell damage developing in the presence of melamine. The relative contents of the top four main proteins corresponding to peak mass-to-charge ratios (m/z) of 4466, m/z 6455, m/z 6514, and m/z 7772 in the MALDI-TOF-MS spectra were all found to be closely correlated with the melamine concentrations. In conclusion, exposure of eukaryotic cells to melamine could inhibit cell growth, cause changes in cytomorphology and even disturb the expression of proteins in a concentration-dependent manner. The described method of examining four sensitive proteins affected by melamine was also proposed to be used in a preliminary study to identify protein biomarkers in T. pyriformis.
Animal Feed/analysis/toxicity ; Biological Markers/analysis ; Food Additives/analysis/toxicity ; Inhibitory Concentration 50 ; Microscopy, Electron, Transmission ; Protozoan Proteins/analysis ; Spectrometry, Mass, Matrix-Assisted Laser De ; Tetrahymena pyriformis/cytology/*drug effects ; Triazines/*toxicity

Introduction: To determine the relationship between participation in supervised and unsupervised therapy, and predictors of participation in supervised therapy during the first post-stroke year. Materials & Methods: Design: Prospective longitudinal study with interviews at admission, discharge, one month, six months and one year after discharge. Setting: Two subacute inpatient rehabilitation units and the community after discharge in Singapore. Participants: 215 subacute non-aphasic stroke patients. Intervention: Participation rate in supervised therapy (at outpatient rehabilitation centres) and unsupervised therapy (at home) defined as proportion of time spent performing therapy as prescribed by the subacute hospital’s multidisciplinary rehabilitation team at discharge. Main Outcome Measure: Predictors of participation in supervised and unsupervised therapy. Results: Patients who participated in supervised therapy (i.e. at an outpatient rehabilitation centre) >25% of the time recommended were more likely to participate in unsupervised therapy (i.e. at home) >75% of the time recommended at one, six and 12 months (crude odds ratio, OR = 4.41 [95%CI:2.09–10.17], 4.45 [95%CI:2.17–9.12], 6.93 [95%CI:2.60–18.48] respectively). Greater participation in supervised therapy at one and six months independently predicted greater participation in supervised therapy at six (adjusted OR=11.64 [95%CI:4.52-29.97]) and twelve months (adjusted OR=76.46 [95%CI:12.52-466.98]) respectively. Caregiver availability at six months independently predicted poorer participation in supervised therapy at 12 months. Conclusion: Interventions to increase participation in supervised therapy in the first post-stroke year should focus on transition of care in the first month after discharge. Further studies are needed to understand why caregiver availability was associated with low participation in supervised therapy.

Objective To investigate the imaging findings and clinicopathological features of osteofibrous dysplasia(OFD)in tibia.Methods The imaging findings of 1 0 cases with OFD in tibia,which were confirmed by pathology and had complete clinical data were analyzed retrospectively.Results The disease occurred in children and the main clinical manifestations were anterior mass and arch deformity of calf.X-ray and CT examinations showed that the lesion distributed along the long axis of tibia and the anterior cortex was involved in 9 cases and the posterior cortex was involved in another one;the midpiece of tibia was involved in 7 cases and the lesion located at the junction area between upper third and middle third of tibia in another 3 cases;9 cases showed multilocular osteolytic lesions within the expanded cortex,manifesting as the high-density bony intervals of different thickness among a number of low-density lesions and another one presented as unilocular osteolytic lesion with sclerosis rim.Lesions manifested as multiple bubble-like intermediate or high signal intensity foci and low-signal interval bands on T2WI in 3 cases of MRI examinations.Microscopic examinations revealed that the lesion was composed of fibrous tissue and trabecular bone,fibrous tissue varied from sparse to dense and trabecular bone was surrounded by a great many osteoblasts and osteoclasts of vary number.The lesion presented as band-shaped distribution with more fibrous tissue and less trabecular bone in the central zones (corresponding to osteolytic destruction areas in radiography)and with trabecular bone gradually increasing in the peripheral zones to form abundant merged lamellar bone (corresponding to bony intervals in radiography).Conclusion OFD in tibia is characterized by the high-density bony intervals(low-signal interval bands on T2WI)of different thickness among a number of low-density lesions(multiple bubble-like intermediate or high signal intensity foci on T2WI)within anterior cortex, which reflects the pathological changes.Typical cases can be diagnosed with a variety of imaging findings and clinical features.