Location of MMPs in human radicular dentin and the effects of MMPs inhibitor on the bonding stability of fiber posts to radicular dentin.

This study explored the location of MMP-2, -3, -8 in human root dentin and the inhibition of EGCG/EGCG-3Me on dentin-originated collagen proteases activities. Also, the study evaluated EGCG/EGCG-3Me modified etch-and-rinse adhesives (Single Bond 2, SB 2) for their bonding stabilities to intraradicular dentin. Immunostaining and liquid chip analysis demonstrated that MMP-2 and MMP-8 are widely distributed in root dentin while MMP-3 shows a higher fluorescence intensity in the middle and apical third of the root. The contents of MMP-2, -3 and -8 varies in different locations of human tooth root and MMP-2 has the highest content than MMP-3 and MMP-8 at each third of teeth root. Both EGCG and EGCG-3Me showed an inhibitory effect on the root dentin-derived MMPs in a concentration dependent manner (P < 0.05) and the inhibitory activity of EGCG-3ME was stronger than that of EGCG at the same concentration (P < 0.05). EGCG and EGCG-3Me were incorporated separately into the adhesive SB 2 at concentrations of 200, and 400 µg/mL respectively. The immediate push-out strength of SB 2 was not compromised by EGCG/EGCG-3Me modification. EGCG/EGCG-3Me modified adhesive had higher push-out strength than SB 2 after thermocycling, showing no correlation with concentration.

The CnB1 p.D102A variant is linked to dilated cardiomyopathy via impaired Calcineurin activity.

BACKGROUND: The role of calcineurin (protein phosphatase 2B (PP2B)) in the pathogenesis of human dilated cardiomyopathy (DCM) has not been fully elucidated. We determined the potential involvement of calcineurin in the pathogenesis of DCM caused by mutations in CnB1, a subunit of calcineurin. METHODS: By whole-exome sequencing, we identified a new CnB1 variant in a Han Chinese proband with cardiomyopathy from a 3-generation family with 2 normal individuals and 3 individuals with familial dilated cardiomyopathy. The potential pathogenic variant was validated by Sanger sequencing. We performed functional and mechanistic experiments in a CnB1-knockin (KI) mouse model and at the cellular level. RESULTS: We detected a rare heterozygous CnB1 variant (p.D102A) in a proband with dilated cardiomyopathy. This variant was localized to the EF hand 3 region of CnB1, where no variants have been previously reported. KI mice harboring the p.D102A variant exhibited decreased cardiac function and cardiac dilatation. Immunoblotting, RT-PCR and immunofluorescence results showed decreased cardiomyocyte size and heart failure-related protein expression. A calcineurin activity assay demonstrated decreased calcineurin activity in the KI mice, accompanied by the decreased ability of CnB1 to bind CnA. CONCLUSIONS: CnB1 p.D102A is a disease-associated variant that confers susceptibility to cardiac dilatation. This variant is associated with impaired calcineurin activity and a subsequent decrease in the ability of CnB1 to bind CnA.

Combined texture analysis of diffusion-weighted imaging with conventional MRI for non-invasive assessment of IDH1 mutation in anaplastic gliomas.

AIM: To examine whether texture analysis (TA) of diffusion-weighted imaging (DWI) combined with conventional magnetic resonance imaging (MRI) could non-invasively predict isocitrate dehydrogenase 1 (IDH1) mutational status in anaplastic gliomas. MATERIALS AND METHODS: Fifty-two patients with histologically confirmed anaplastic glioma was reviewed retrospectively. Conventional MRI was evaluated using the Visually Accessible Rembrandt Images (VASARI) scoring system. TA of DWI based on the entire tumour volume was compared between IDH1-mutant and wild-type tumours by using unpaired Student's t-test. Receiver operating characteristic curve (ROC) and logistic regression were used to assess their diagnostic performance. RESULTS: Significant statistical differences in VASARI features and TA of DWI were observed between IDH1-mutant and wild-type tumours (all p<0.05). Using multivariable logistic regression, the proportion of the tumour that was non-enhancing and the entropy of apparent diffusion coefficient (ADC) were found to possess higher prediction potential for IDH1 mutation with areas under the ROC curve (AUC) of 0.918 and 0.724, respectively. A combination of these for the identification of IDH1 mutations improved the AUC to 0.954, with a sensitivity and a specificity of 81% and 96%. CONCLUSIONS: The combined assessment of the conventional MRI and TA of DWI were useful for predicting IDH1 mutation in anaplastic gliomas.

Trigeminal neuralgia caused by a choroid plexus papilloma of the cerebellopontine angle: case report and review of the literature.

This report describes a 59-year old woman with a rare choroid plexus papilloma of the cerebellopontine angle presenting with trigeminal neuralgia. The patient was admitted complaining of a 12-year history of paroxysmal lancinating pain throughout the right side of her face. Treatment with carbamazepine, Chinese medicine and a peripheral neurectomy had not relieved the pain. At operation, a 0.5 x 0.5 x 0.5 cm neoplasm was found in the cerebellopontine angle, which was firmly adherent to the roots of the seventh and eighth cranial nerves and the brainstem. There was no apparent tumour bulk or vascular compression around the trigeminal nerve root entry zone. Subtotal tumour excision and selective partial rhizotomy were performed. The patient's facial pain gradually resolved. Involvement of the trigeminal nucleus in the brainstem by the cerebellopontine angle tumour is suggested as the possible cause for trigeminal neuralgia in this case.

[Genetic diversity and differentiation of cultivated Fagoyrum tataricum populations from three counties in south Liangshan Automomous Prefecture of Yi Nationality, Sichuan, China].

Genetic diversity and differentiation among 8 cultivated populations of Fagopyrum tataricum from the counties of Jinyang, Leibo and Miyi in south Liangshan Autonomous Prefecture of Yi Nationality, Sichuan Province, China were investigated using allozyme electrophoresis. The allozymic diversity is roughly correlated with agrobiological features. The results suggest that genetic diversity of F. tataricum is quite high. The mean number of alleles per locus A is 1.8; the percentage of polymorphic loci P is 46.6%, and the mean observed heterozygosities Ho and the mean expected heterozygosities He are 0.187 and 0.218 respectively, the ratios of gene diversities of heterozygosities Fsr is 0.22, which indicates that there is 22 percent of genetic differentiation among populations, and suggests that for protecting genetic resources all the populations should be included in.

[Genetic diversity of Fagoyrum tataricum cultivated in north Liangshan Prefecture of Yi Nationality, Sichuan, China].

In the present paper is stated the accomplishment of the studies of 17 populations of cultivated Fagopyrum tataricum (L.) Gaertn. from the counties of Yuexi and Ganluo in North Liangshan Autonomous Prefecture of Yi Nationality, Sichuan Province, China by means of starch gel electrophoresis and cluster analysis of agrobiology features. Seven enzymes, and 15 loci were assessed. The result shows that the genetic diversity of F. tataricum within population is higher than in the South Prefecture and in species F. esculentum from other areas. The A, P, Ho and He are 1.9, 52.1%, 0.190 and 0.262 respectively. The FST is 0.199 which is close to the average level of wild plants. A conservation strategy of the genetic resource of F. tataricum is suggested. Two populations of local variety "Youchiqiao" have the richest genetic diversity, P = 60.0%, Ho = 0.260 and 0.301 and they should be protected particularly. Two populations of local variety "Xiaomiqiao" with higher genetic diversity, as well as three populations of local varieties of "Qiukuqiao", "Equkuqiao" and "Geluokuqiao" with special genetic position should be protected too.

Retinoid-dependent pathways suppress myocardial cell hypertrophy.

Utilizing an in vitro model system of cardiac muscle cell hypertrophy, we have identified a retinoic acid (RA)-mediated pathway that suppresses the acquisition of specific features of the hypertrophic phenotype after exposure to the alpha-adrenergic receptor agonist phenylephrine. RA at physiological concentrations suppresses the increase in cell size and induction of a genetic marker for hypertrophy, the atrial natriuretic factor (ANF) gene. RA also suppresses endothelin 1 pathways for cardiac muscle cell hypertrophy, but it does not affect the increase in cell size and ANF expression induced by serum stimulation. A trans-activation analysis using a transient transfection assay reveals that neonatal rat ventricular myocardial cells express functional RA receptors of both the retinoic acid receptor and retinoid X receptor (RAR and RXR) subtypes. Using synthetic agonists of RA, which selectively bind to RXR or RAR, our data indicate that RAR/RXR heterodimers mediate suppression of alpha-adrenergic receptor-dependent hypertrophy. These results suggest the possibility that a pathway for suppression of hypertrophy may exist in vivo, which may have potential therapeutic value.

The combined method of transplantation of foetal substantia nigra and stereotactic thalamotomy for Parkinson's disease.

Five cases with late Parkinson's disease improved following treatment with a combination of foetal substantia nigra grafts and stereotactic thalamotomy. The average Webster's score decreased from 21 to 11 points. This modified method is simple, safe and effective.

A new serum-responsive, cardiac tissue-specific transcription factor that recognizes the MEF-2 site in the myosin light chain-2 promoter.

We have identified a serum-responsive, cardiac tissue-specific transcription factor, BBF-1, that recognizes an AT-rich sequence (element B), identical to the myocyte enhancer factor (MEF-2) target site, in the cardiac myosin light chain-2 (MLC-2) promoter. Deletion of the element B sequence alone from the cardiac MLC-2 promoter causes, as does that of the MEF-2 site from other promoters and the enhancer of skeletal muscle genes, a marked reduction of transcription. BBF-1 is distinguishable from cardiac MEF-2 on the basis of immunoprecipitation with an antibody which recognizes MEF-2 but not BBF-1. Unlike MEF-2, BBF-1 is present exclusively in nuclear extracts from cardiac muscle cells cultured in a medium containing a high concentration of serum. Removal of serum from culture medium abolishes BBF-1 activity selectively with a concomitant loss of the positive regulatory effect of element B on MLC-2 gene transcription, indicating that there is a correlation between the BBF-1 binding activity and the tissue-specific role of the element B (MEF-2 site) sequence. The loss of element B-mediated activation of transcription is reversed following the refeeding of cells with serum-containing medium. These data demonstrate that cardiac muscle cells contain two distinct protein factors, MEF-2 and BBF-1, which bind to the same target site but that, unlike MEF-2, BBF-1 is serum inducible and cardiac tissue specific. BBF-1 thus appears to be a crucial member of the MEF-2 family of proteins which will serve as an important tool in understanding the regulatory mechanism(s) underlying cardiogenic differentiation.

A single transcription factor binds to two divergent sequence elements with a common function in cardiac myosin light chain-2 promoter.

The cardiac myosin light chain-2 (MLC-2) gene promoter contains several positive and negative cis-acting sequences that are involved in the regulation of its expression. We describe here the properties of two activator sequences, elements A and P, and their DNA-binding factors (ABFs). Element A (CCAAAAGTGG), located at -61, has homology with the evolutionarily conserved sequence CC(A/T)6GG, present in the genes of many contractile proteins. Element P (TAACCTTGAAAGC), located 114 bp upstream of element A, is conserved in both chicken and rat cardiac MLC-2 gene promoters. Deletion mutagenesis demonstrated that these two elements are involved in the positive regulation of MLC-2 gene transcription. At least two sequence-specific element A-binding proteins, ABF-1 and ABF-2, were identified by gel shift analysis of the fractionated cardiac nuclear proteins. ABF-1 binds to element A with strict dependence on the internal element A sequence AAAAGT. In contrast, ABF-2 exhibits a relaxed sequence requirement, as it recognizes the consensus CArG and CCAAT box sequences as well. ABF-2 also recognizes the distal element P despite the fact that the sequences of elements A and P are divergent. DNase I footprinting, methylation interference, and gel shift analyses demonstrated unequivocally that the element A-DNA affinity-purified protein ABF-2 binds to element P with sequence specificity. Since both elements A and P play a positive regulatory role in MLC-2 gene transcription and bind to a single protein (ABF-2), it would appear that ABF-2 is a key transcription factor with the ability to recognize divergent sequence elements involved in a common regulatory pathway during myogenesis.

Mechanism of tissue-specific transcription: interplay between positive and negative regulatory factors.

At least four regulatory cis-acting DNA sequences, CCAAAAGTGG (element A), TTATTTTTA (element B), TATTTATT (element C), and TATTACCTTTAT (element S), were identified in cardiac myosin light chain-2 (MLC2) proximal promoter as target sites for sequence-specific binding of nuclear proteins. For muscle-specific transcription, the proximal promoter (-53 to +1) consisting only of elements B and C is required. Addition of element A to this promoter results in a muscle-specific up-regulation, whereas the addition of element S exerts a negative effect on transcription. The negative and positive regulatory effects of elements S and A respectively were demonstrated by site-specific mutations of the promoter following transient transfection of cardiac muscle cells in culture. Elements S and A interact separately with distinct nuclear protein factor present in both muscle and non-muscle cells, even though their regulatory activities are restricted to muscle cells. Among the multiple complexes resulting from the interaction of nuclear proteins and elements S and A DNAs, one requires both S and A sequences together for binding. Element B, which exerts a muscle-specific positive effect on transcription, binds to a nuclear protein present in cardiac muscle, but not in non-muscle cells. DNA-protein binding assays and mutational analysis of the MLC2 promoter suggest that the contribution of the functionally opposed cis-elements depends upon an interplay between the positively and negatively acting DNA-binding proteins via protein-protein interactions to mediate opposite regulatory effects on gene transcription.