Is one-time carbon monoxide intoxication harmless? Evaluation by argyrophilic nucleolar-organizing regions staining method

In carbon monoxide (CO) poisoning, CO affects the oxygen-carrying capacity of the hemoglobin molecule. Nucleolar-organizing regions (NORs) are genetic loci on chromosomes that are composed of ribosomal DNA and proteins. NORs can be stained with silver. A total of 18 rats were exposed to CO in three different concentrations (1000, 3000, and 5000 ppm) with 6 rats as controls. The animals were euthanized 7 days after CO intoxication. Lung tissues were taken, embedded in paraffin blocks, and sectioned at 5 μm thickness. Argyrophilic nucleolar-organizing region (AgNOR) staining was carried out. One hundred nuclei per individual were evaluated, and total AgNOR number per total nuclear number and total AgNOR area per nuclear area (TAA/NA) for each nucleus were analyzed. The CO exposure groups had significantly higher TAA/NA values and AgNOR numbers than the control group ( p < 0.05). Although the differences between 1000 ppm and the other two CO-exposed groups were meaningful ( p < 0.05) in the TAA/NA values, there were no differences among the CO exposure groups for the AgNOR number ( p > 0.05). The increase in TAA/NA value depends on the increase in the CO exposure. Significant correlations between both the AgNOR values and histopathological scoring methods were found. Therefore, AgNOR staining method may be used as an indirect indicator for evaluating the degree of cell damage rate.

Cryopreservation of eucalyptus genetic resources

The long-term preservation of forest genetic resources is a vital part of preserving our forest crops for future generations. Unfortunately, there are few genebanks dedicated to forest trees and very few methods for long-term preservation of forest genetic resources collections aside from field plantings of a limited number of seed-derived or elite clonal individuals. The use of cryopreservation for the long-term storage of elite germplasm is increasingly being used for the long-term preservation of clonal agronomic crops but for forest trees, such as Eucalyptus, the methodology for cryopreservation of diverse genetic resources collections has not been established. We report the successful cryopreservation of a germplasm collection of in vitro shoot cultures of thirteen Eucalyptus spp. lines consisting of two E. grandis x E. camaldulensis lines, seven E. urophylla x E. grandis lines, one E. grandis line, two E. grandis x E. urophylla lines, and one E. camaldulensis line. In a comparison of two cryopreservation methods, sucrose sensitivity limited the application of encapsulation-dehydration. However, with droplet-vitrification, all thirteen lines had good survival after cryopreservation in liquid nitrogen. A 30 min exposure to Plant Vitrification Solution 2 (PVS2) yielded post-liquid nitrogen survival between 38% and 85% depending on the line. One hundred shoot tips from all thirteen lines are currently in long-term storage as a germplasm collection.

[ECG changes in primary neurological disorders, systemic diseases and primary cardioymopathies]

ECG diagnostic is not only an easy to use, cost efficient, extensively available method for cardiological patients, but also a potential tool in diagnostic for other morbidities. As a well-known example, cerebral hemorrhage and ischemia can show an ECG, that resembles an acute coronary syndrome. Furthermore systemic diseases may show characteristic ECG; often as a malfunction of the conductive system (e.g., AV block). Exclusion of cardiac involvement when dealing with sarcoidosis is important, and the ECG may be a first hint. Besides, in Ixodid endemic areas a cardiological manifestation of Borreliosis should be considered. ECG may also show almost specific findings in primary cardiomyopathies, such as the "pseudo-infarction Q - wave" in hypertrophic cardiomyopathy or "epsilon potentials" in arrhythmogenic right ventricular cardiomyopathy. The takotsubo cardiomyopathy commonly reveals transient ST-segment elevation and therefore depicts an important differential diagnosis of acute coronary syndromes.

Survival of diced and block cartilage grafts in combination with injectable calcium hydroxylapatite

OBJECTIVES/HYPOTHESIS

Dorsal nasal irregularities after trauma, and various procedures such as excessive nasal hump resection, are major problems for patients who have undergone rhinoplasty. Many grafts have been described for the correction of dorsal nasal irregularities. In this study, we used an injectable implant, in combination with diced or block cartilage grafts, to test the efficacy of injectable calcium hydroxylapatite on the survival of diced or block cartilage grafts.

STUDY DESIGN

Prospective, controlled, parallel group animal study.

METHODS

Fourteen New Zealand white rabbits were used. Block cartilage and diced cartilage grafts, alone and in combination with injectable calcium hydroxylapatite, were placed subcutaneously in the rabbits' dorsal thoracolumbar region. On the 90th day following surgery, the graft areas were extracted immediately after the rabbits were sacrificed. Pathological examination was conducted on all specimens.

RESULTS

The pathologic and histochemical findings were compared between groups. There was chronic inflammation observed in all of the groups. However, none of the groups had metaplastic bone formation or calcification. The group that received diced cartilage in combination with the injectable implant received the highest scores for peripheral chondrocyte proliferation, matrix collagen, elastic fiber, and proteoglycan content (P < 0.05). A comparison of the block and diced cartilage grafts revealed that peripheral chondrocyte proliferation was more pronounced in the diced cartilage grafts (P < 0.05).

CONCLUSION

The use of calcium hydroxylapatite in combination with diced cartilage grafts does not have any long-term negative effects on chondrocyte viability.

Calculation of pediatric femoral fracture rotation from direct roentgenograms

Background

Radiologic determination of pediatric femoral fracture rotation has been debated. Measuring the antetorsion angle of the fractured femur by computed tomography and comparing it with the opposite side has been the method of choice for this purpose. However, no simple method for direct measurement of femoral fracture rotation exists in the literature. In this study, our aim was to test a mathematical method of measuring the axial plane malrotation from direct roentgenograms.

Materials and methods

A pediatric femoral shaft fracture model was produced. The bone was secured to a wooden frame that allowed the distal part of the fracture to rotate around an axis. Radiographs were taken at known intervals of rotation ranging from the neutral position to 60° external rotation and to 60° internal rotation in 5° increments of rotation. Five independent, blinded observers measured the radiographs and calculated the fracture rotation according to a standard formula. Calculated rotation values were compared with known rotation values.

Results

Calculated rotation values were close to actual rotation values throughout the arc of rotation. The mean absolute error of five observers for all measurements of external and internal rotation was 3.97° (±0.83). The correlation coefficient between calculated and actual rotation values was 0.9927. The interobserver intraclass correlation coefficient for calculated rotation was 0.997.

Conclusions

Absolute error and correlation coefficient values indicate that this method is accurate and reliable in determining the fracture rotation.

Cryopreservation of Thymus cariensis and T. vulgaris shoot tips: comparison of three vitrification-based methods

Thymus is an important genus of the Lamiaceae family, comprising more than 400 perennial aromatic thyme species, which are used extensively for medicinal and culinary purposes. The present study focused on the development of cryopreservation procedures for Thymus vulgaris and T. cariensis, the latter being an endemic and endangered species of Turkey. For cryopreservation of T. vulgaris shoot tips, PVS2-based one-step freezing methods, i.e., PVS2 vitrification, encapsulation-vitrification and droplet-vitrification, were compared. Cold hardening and sucrose preculture were also optimized before the cryopreservation trials. For T. cariensis, a droplet-vitrification method was applied to cold-hardened shoot tips, and after sucrose preculture. In all the methods tested, PVS2 was applied for up to 120 min. The best T. vulgaris cryopreservation was achieved with a droplet-vitrification method, that involved 2-weeks cold hardening of shoot cultures, 48 h preculture of shoot tips on MS medium supplemented with 0.25 M sucrose, and a 90 min PVS2 treatment in droplets. After direct immersion in LN, thawing and plating, 80% of shoot-tips recovered. Post-thaw recovery was significantly lower when the same procedure was applied to T. cariensis shoot tips; however also here 90 min PVS2 treatment produced the highest survival (25 percent) and recovery (25 percent) levels.

4D-QSAR study of HEPT derivatives by electron conformational-genetic algorithm method

In this work, the EC-GA method, a hybrid 4D-QSAR approach that combines the electron conformational (EC) and genetic algorithm optimization (GA) methods, was applied in order to explain pharmacophore (Pha) and predict anti-HIV-1 activity by studying 115 compounds in the class of 1-[(2-hydroxyethoxy)-methyl]-6-(phenylthio) thymine (HEPT) derivatives as non-nucleoside reverse transcriptase inhibitors (NNRTIs). The series of NNRTIs were partitioned into four training and test sets from which corresponding quantitative structure-activity relationship (QSAR) models were constructed. Analysis of the four QSAR models suggests that the three models generated from the training and test sets used in previous works yielded comparable results with those of previous studies. Model 4, the data set of which was partitioned randomly into two training and test sets with 11 descriptors, including electronical and geometrical parameters, showed good statistics both in the regression (r2(training) )= 0.867, r2test = 0.923) and cross-validation (q (2) = 0.811, q2(ext1) = 0.909, q2(ext2) = 0.909) for the training set of 80 compounds and the test set of 27 compounds. The prediction of the anti-HIV-1 activity of HEPT compounds by means of the EC-GA method allowed for a quantitatively consistent QSAR model. In addition, eight novel compounds never tested experimentally have been designed theoretically using model 4.