Investigation of mucus obtained from different fish species on the acute pain induced with scalpel incision in paw of rats

No comparative study could be found for the analgesic activity of mucuses from theOncorhynchus mykiss (OM), Salvelinus fontinalis (SF),Salmo coruhensis (SC), Acipenser gueldenstaedtii (AG),and Acipenser baerii (AB) fish species in the literature. We aimed toinvestigate the effects of mucuses obtained from the abovementioned fish species onscalpel incision-induced pain in the rat paw and to examine the role ofoxidant/antioxidant parameters and COX-2 gene expression in the analgesic activities.Animals were divided into groups: SIC (scalpel incision; SI), SIDS (SI+25 mg/kg diclofenacsodium), SOM (SI+25 mg/kg OM mucus), SFM (SI+25 mg/kg SF mucus), SCM (SI+25 mg/kg SCmucus), SAgM (SI+25 mg/kg AG mucus), SAbM (SI+25 mg/kg AB mucus), and HG (healthy). Thepaw pain thresholds were measured with a Basile algesimeter before and after diclofenacsodium (DS) or mucus administration, and then the rats were euthanized with thiopentalsodium. Oxidant/antioxidant and COX-2 gene expression parameters were measured in pawtissues. OM, SC, AG, and AB fish mucuses could not decrease the SI-induced pain. However,SF fish mucus prevented this pain by 69% after the first hour and by 58.3% after the thirdhour. DS was shown to suppress pain more weakly than SF, preventing the pain by 62.1% and50.0% after the first and third hours, respectively. SF mucus and DS significantlyinhibited increase of COX-2 gene expression, while other fish mucuses could not. None ofthe fish mucuses except SF mucus in conjunction with DS could significantly inhibit theincrease in oxidant parameters and decrease in antioxidants. SF fish mucus should becomparatively assessed in clinical practice for treatment of postoperative pain.     

Reproducibility and Prognostic Value of WHO1973 and WHO2004 Grading Systems in TaT1 Urothelial Carcinoma of the Urinary Bladder

Background

European treatment guidelines of TaT1 urinary bladder urothelial carcinomas depend highly on stage and WHO1973-grade but grading reproducibility is wanting. The newer WHO2004 grading system is still debated and both systems are currently used.

Aims

To compare reproducibility and prognostic value (of stage progression) of the WHO1973 and WHO2004.

Methods

One hundred and ninety-three primary urothelial carcinomas were reviewed. Follow-up data were retrieved from the patient records. Kappa statistics and Harrell''s C-index were used.

Results

Median follow-up was 75 months (range 1–127). 17 patients (9%) progressed, 82% of these within and 18% after 60 months. The distribution of WHO73-grades 1, 2 and 3 was 23%, 51% and 26%, interobserver agreement for each individual grade was 66% (kappa = 0.68), while for grades 1&2 versus 3 89% (kappa = 0.68). Intraobserver reproducibility was 68–63% for WHO73 and 88–89% for WHO73 as 1&2 vs.3. Progression free survival rates at 5 years were 95% (grade 1), 98% (grade 2) and 82% (grade 3) and 96% and 82% for grades 1&2 versus 3 (Hazard Ratio, HR, 5.4, p = 0.003). Using WHO2004, 62% were low grade and 38% high grade, inter-observer agreement 87% (kappa = 0.70), intraobserver reproducibility 93%, and progression free 5-year survival rates 97% and 85% (HR 6.6, p = 0.004). Positive and negative predictive values for stage progression within 5 years for the WHO73 (1&2 vs. 3) were 18% and 96%, and 15% and 97% for the WHO04. Using Harrell''s C-index, none of the grading systems was prognostically superior.

Conclusion

None of the grading systems is prognostically stronger than the others. Most importantly, inter-observer reproducibility and sensitivities for stage progression of both systems are low and need improvement for optimal treatment.     

Time-frequency analysis of visual evoked potentials for interhemispheric transfer time and proportion in callosal fibers of different diameters

This study is an extension of the experimental research of Nalçac et al., who presented 16 subjects with a reversal of checkerboard pattern as stimuli in the right visual field or left visual field and recorded EEG at O1, O2, P3, and P4. They applied the chosen bandpass filters (4–8, 8–15, 15–20, 20–32 Hz) to the VEPs of subjects and obtained four different components for each VEP. The first aim of this study is to improve the previous report using some methods in time-frequency domain to estimate interhemispheric delays and amplitudes in a time window. Using the improved estimates of interhemispheric delays, the second aim is to estimate the proportion of callosal fibers of different diameters that are activated by visual stimuli by comparing amplitudes of VEPs in different frequency bands. If the relation between frequency components of VEP and delays for callosal fibers of different dimension were reliable, it would give us an opportunity to deal with amplitude of bandpass-filtered VEPs in order to see approximately the proportion of these fibers activated by a certain stimulus. By using frequency-dependent shifts in time and maximizing the cross correlation of direct VEP (DVEP–VEP obtained from contralateral hemisphere)–indirect VEP (IVEP–VEP obtained from ipsilateral hemisphere) pairs in the time-frequency domain, we examined the delay not only at P100 and N160 peaks but along a meaningful time interval as well. Furthermore, by shifting back the IVEP according to the delay estimated at each time window, both the amplitudes and energies of the synchronized DVEP–IVEP pairs were compared at the chosen frequency bands. The percentages of IVEPs at each band was then examined further in conjunction with the distribution of axon diameters in the posterior pole of the CC, questioning the relation between the distributions of the axon diameters and activations at each band. We established an energy definition to express the activation in the fibers. When the energy percentages of IVEPs in theta and alpha were totaled, they were found to be between 76.2% and 81.6%, which is close to the value 74–77% for fibers of 0.4–1 m in diameter obtained from anatomical study of human CC. The sum of energy percentages in the beta1 and beta2 bands was between 20.1% and 24.2%, which probably reflects the proportion of activation of callosal fibers 1–3 m in diameter.     

Neural Crest Cells Isolated from the Bone Marrow of Transgenic Mice Express JCV T-Antigen

JC virus (JCV), a common human polyomavirus, is the etiological agent of the demyelinating disease, progressive multifocal leukoencephalopathy (PML). In addition to its role in PML, studies have demonstrated the transforming ability of the JCV early protein, T-antigen, and its association with some human cancers. JCV infection occurs in childhood and latent virus is thought to be maintained within the bone marrow, which harbors cells of hematopoietic and non-hematopoietic lineages. Here we show that non-hematopoietic mesenchymal stem cells (MSCs) isolated from the bone marrow of JCV T-antigen transgenic mice give rise to JCV T-antigen positive cells when cultured under neural conditions. JCV T-antigen positive cells exhibited neural crest characteristics and demonstrated p75, SOX-10 and nestin positivity. When cultured in conditions typical for mesenchymal cells, a population of T-antigen negative cells, which did not express neural crest markers arose from the MSCs. JCV T-antigen positive cells could be cultured long-term while maintaining their neural crest characteristics. When these cells were induced to differentiate into neural crest derivatives, JCV T-antigen was downregulated in cells differentiating into bone and maintained in glial cells expressing GFAP and S100. We conclude that JCV T-antigen can be stably expressed within a fraction of bone marrow cells differentiating along the neural crest/glial lineage when cultured in vitro. These findings identify a cell population within the bone marrow permissible for JCV early gene expression suggesting the possibility that these cells could support persistent viral infection and thus provide clues toward understanding the role of the bone marrow in JCV latency and reactivation. Further, our data provides an excellent experimental model system for studying the cell-type specificity of JCV T-antigen expression, the role of bone marrow-derived stem cells in the pathogenesis of JCV-related diseases and the opportunities for the use of this model in development of therapeutic strategies.     

Pectin-Lipid Self-Assembly: Influence on the Formation of Polyhydroxy Fatty Acids Nanoparticles

Nanoparticles, named cutinsomes, have been prepared from aleuritic (9,10,16-trihidroxipalmitic) acid and tomato fruit cutin monomers (a mixture of mainly 9(10),16-dihydroxypalmitic acid (85%, w/w) and 16-hydroxyhexadecanoic acid (7.5%, w/w)) with pectin in aqueous solution. The process of formation of the nanoparticles of aleuritic acid plus pectin has been monitored by UV-Vis spectrophotometry, while their chemical and morphological characterization was analyzed by ATR-FTIR, TEM, and non-contact AFM. The structure of these nanoparticles can be described as a lipid core with a pectin shell. Pectin facilitated the formation of nanoparticles, by inducing their aggregation in branched chains and favoring the condensation between lipid monomers. Also, pectin determined the self-assembly of cutinsomes on highly ordered pyrolytic graphite (HOPG) surfaces, causing their opening and forming interconnected structures. In the case of cutin monomers, the nanoparticles are fused, and the condensation of the hydroxy fatty acids is strongly affected by the presence of the polysaccharide. The interaction of pectin with polyhydroxylated fatty acids could be related to an initial step in the formation of the plant biopolyester cutin.     

Perceptions of family medicine and career choice among first year medical students: a cross-sectional survey in a Turkish medical school

Public attitudes to family medicine in Turkey have lagged behind its rapid academic development. The effect of undergraduate training in primary care on medical students' attitudes to family medicine has not been assessed. Objectives of this study were to assess the attitudes of first year medical students at Uludag University School of Medicine in Bursa, Turkey to family medicine and to determine their career aspirations. The study was a survey of the first year medical class in 2003-2004. The response rate was 95% (248/261 students). Students were positive about their choice of medicine as a career but had negative opinions of general practice. Female students were more positive in this respect. Initial preference was for specialization in fields other than general practice with little knowledge of the academic specialty of family medicine. Greater undergraduate exposure to family medicine is needed in order to increase knowledge of the field and influence student career choices.     

Mcl-1 determines the Bax dependency of Nbk/Bik-induced apoptosis

B cell lymphoma 2 (Bcl-2) homology domain 3 (BH3)–only proteins of the Bcl-2 family are important functional adaptors that link cell death signals to the activation of Bax and/or Bak. The BH3-only protein Nbk/Bik induces cell death via an entirely Bax-dependent/Bak-independent mechanism. In contrast, cell death induced by the short splice variant of Bcl-x depends on Bak but not Bax. This indicates that Bak is functional but fails to become activated by Nbk. Here, we show that binding of myeloid cell leukemia 1 (Mcl-1) to Bak persists after Nbk expression and inhibits Nbk-induced apoptosis in Bax-deficient cells. In contrast, the BH3-only protein Puma disrupts Mcl-1–Bak interaction and triggers cell death via both Bax and Bak. Targeted knockdown of Mcl-1 overcomes inhibition of Bak and allows for Bak activation by Nbk. Thus, Nbk is held in check by Mcl-1 that interferes with activation of Bak. The finding that different BH3-only proteins rely specifically on Bax, Bak, or both has important implications for the design of anticancer drugs targeting Bcl-2.     

Protein dynamics and monomer-monomer interactions in AntR activation by electron paramagnetic resonance and double electron-electron resonance

The Anthracis repressor (AntR) is a Mn(II)-activated DNA binding protein that is involved in the regulation of Mn(II) homeostasis in Bacillus anthracis. AntR is structurally and functionally homologous to Mn(II)-activated repressor from Bacillus subtillis (MntR). Our studies on AntR focus on metal-regulated activation of the protein. Line shape analysis of continuous wave electron paramagnetic resonance (EPR) spectra showed that metal binding resulted in a general reduction of backbone dynamics and that there were no further changes in backbone motion upon DNA binding. Double electron-electron resonance (DEER) pulsed EPR spectroscopy was used to measure distances between nitroxide spin labels strategically placed in dimeric AntR. The DEER data were analyzed assuming Gaussian distributions for discrete populations of spins. A structural model for AntR was built from homology to MntR, and the experimentally measured distances were simulated to distinguish between spin label and backbone motions. Together with the computational analysis, the DEER results for apo-AntR indicated relatively narrow conformational distributions for backbone residues at the dimer interface and near the metal binding site. No significant changes were observed on these sites in the presence of metal or DNA. On the other hand, the distribution of the conformers and the distances between the putative DNA binding helices decreased upon metal binding. These results suggest that the DNA binding region of AntR shows large amplitude backbone motions in the absence of metal, which may preclude sequence-specific binding to promoter sites. Metal binding narrows the range of conformations accessible in this region and shortens the mean distance between the DNA binding helices, probably resulting in alignment that optimizes promoter recognition and binding.     

Small interfering RNA-mediated xCT silencing in gliomas inhibits neurodegeneration and alleviates brain edema

Neurodegeneration and brain edema are hallmarks of human malignant brain tumors. Here we show that genetic or pharmacological inhibition of the glutamate transporter xCT (X(c-) system, encoded by SLC7a11) in vivo leads to abrogated neurodegeneration, attenuated perifocal edema and prolonged survival. These results show a crucial role for xCT in glioma-induced neurodegeneration and brain edema, corroborating the concept that edema formation may be in part a consequence of peritumoral cell death.     

Phosphorylation mutants of JC virus agnoprotein are unable to sustain the viral infection cycle

Many eukaryotic and viral regulatory proteins are known to undergo posttranslational modifications including phosphorylation, which plays a critical role in many aspects of cell function. Previous studies from our and other laboratories indicated that the JC virus (JCV) late regulatory protein, agnoprotein, plays an important role in the JCV life cycle. Agnoprotein contains several potential phosphorylation sites, including Ser7, Ser11, and Thr21, which are potential targets for the serine/threonine-specific protein kinase C (PKC). In this study, we investigated the functional significance of these phosphorylation sites for the activity of agnoprotein. In vitro and in vivo kinase assays demonstrated that agnoprotein is a target for phosphorylation by PKC. In addition, each of the PKC phosphorylation sites was mutated to Ala singly and in combination, and the effects of these mutations on the JCV life cycle were analyzed. Although the expression of each mutant agnoprotein was detectable during the infection cycle, virus containing each of these mutations failed to propagate. These results contrast with those obtained with an agnoprotein start codon point (Pt) mutant where agnoprotein expression was completely inhibited. The Pt mutant was viable but replicates less efficiently than the wild type (WT). Moreover, conservative substitutions at PKC phosphorylation sites (Ser7, Ser11, and Thr21 to Asp) resulted in a viable virus, which further demonstrate the importance of these sites on agnoprotein function. Further analysis of the mutants by viral release assay and electron microscopy studies revealed that viral particles were efficiently released from infected cells and morphologically indistinguishable from those of WT but were deficient in DNA content. This may account for the defective propagation of the mutants. These results imply that phosphorylated forms of agnoprotein may have essential functions in the viral life cycle and serve as potential targets for therapeutic interventions to limit JCV propagation and JCV-induced diseases.