The sirtuin family in health and disease.

Sirtuins (SIRTs) are nicotine adenine dinucleotide(+)-dependent histone deacetylases regulating critical signaling pathways in prokaryotes and eukaryotes, and are involved in numerous biological processes. Currently, seven mammalian homologs of yeast Sir2 named SIRT1 to SIRT7 have been identified. Increasing evidence has suggested the vital roles of seven members of the SIRT family in health and disease conditions. Notably, this protein family plays a variety of important roles in cellular biology such as inflammation, metabolism, oxidative stress, and apoptosis, etc., thus, it is considered a potential therapeutic target for different kinds of pathologies including cancer, cardiovascular disease, respiratory disease, and other conditions. Moreover, identification of SIRT modulators and exploring the functions of these different modulators have prompted increased efforts to discover new small molecules, which can modify SIRT activity. Furthermore, several randomized controlled trials have indicated that different interventions might affect the expression of SIRT protein in human samples, and supplementation of SIRT modulators might have diverse impact on physiological function in different participants. In this review, we introduce the history and structure of the SIRT protein family, discuss the molecular mechanisms and biological functions of seven members of the SIRT protein family, elaborate on the regulatory roles of SIRTs in human disease, summarize SIRT inhibitors and activators, and review related clinical studies.

[Differences in dielectric properties between mucosal and serosal surface of malignant colorectal tissues, adjacent tissues at 1 cm and 3 cm and normal colorectal tissues].

OBJECTIVE: To investigate the differences in dielectric properties (relative permittivity and conductivity) between the mucosal surface and serosal surface of malignant colorectal tissues, adjacent tissues at 1 cm and 3 cm from the tumor focus and normal colorectal tissues. METHODS: The dielectric properties of the mucosal and serosal surface of malignant colorectal tissues, adjacent tissues (1 cm and 3 cm) and normal colorectal tissues from 39 patients with colorectal cancer were measured with an open-ended coaxial probe within the frequency range of 50 MHz-3 GHz, and the corresponding dielectric properties were analyzed respectively; statistical tests of the data were used to analyze the dielectric properties at 6 specific frequency points. RESULTS: The dielectric properties were significantly higher in the malignant mucosa surface than in the adjacent tissues and normal colorectal tissues at the 6 specific frequency points (P<0.01). The dielectric properties decreased progressively in adjacent tissues at 1 cm and 3 cm and normal mucosa surface. The mucosal and serosal surface of malignant tissues showed significant differences in dielectric properties at 64 MHz, 128 MHz, 298 MHz, 433 MHz, and 915 MHz (P<0.01) but not at 2450 MHz (P>0.01), but such differences were not observed in normal tissues (P>0.01). CONCLUSION: The dielectric properties of the mucosal surface of the mucosal decrease in the order of malignant colorectal tissue, adjacent tissues at 1 cm and 3 cm from the tumor foci and normal colorectal tissues. The dielectric properties are higher in the mucosal surface than in the serosal surface in the malignant tissue, but comparable in normal colorectal tissues.

A pair of new isocoumarin epimers from soil fungus Hypoxylon sp.

In our research on novel secondary metabolites from micro-organisms, two new (1-2) and four known dihydroisocoumarins (3-6) were derived from soil fungus Hypoxylon sp. Their structures were determined with extensive NMR data analysis and ECD calculation comparing with those of experimental CD spectra. Interestingly, compounds 1 and 2 possessed the same planar structure and very similar NMR data, suggesting 1 and 2 were a pair of epimers at either C-3 or at C-4, confirmed by the totally opposite cotton effect around 250 nm in the CD spectra of 1 and 2. Moreover, for the first time, we revealed that the CD absorption peak at 250 nm was dominated by C-3 orientation, rather than the orientation of C-3 substituents, by intensive ECD investigations.

Correlation analysis of facial profile in patients with skeletal Class Ⅱ malocclusion and changes of hard and soft tissue after orthodontic treatment combined with orthognathic surgery / 口腔疾病防治

Objective @#To investigate the effect of orthodontic and orthognathic treatment on patients with skeletal Class Ⅱ malocclusionby studying the changes of soft and hard tissues in maxillofacial region, to analyze the correlation between soft and hard tissues in patients with skeletal classⅡ in order to provide reference and guidance for combination therapy.@*Methods @#23 patients with skeletal classⅡmalocclusion treated by combined orthodontic and surgical treatment were selected, 21 parameters that can reflect the soft and hard tissue and the facial appearance were recorded in the imaging data before and after orthodontic-orthognathic treatment, The correlation between the soft and hard tissue of the patients before treatment was analyzed.@*Results @#There were significant differences between the before and after orthodontic-orthgnathic treatment in the 19 of above mentioned parameters, except for ANS-Me/N-Me(%) and Pg-Pg′ (mm). By analyzing the correlation between the hard tissue index and the soft tissue profile of the patients before treatment, it can be found that the facial aesthetics is influenced by many hard tissue parameters.@*Conclusion @# The effect of orthodontic and orthognathic technique in the treatment of skeletal ClassⅡ malocclusion is considerable. Hard tissue profile of patients with skeletal ClassⅡ malocclusion forms the basis and support of soft tissue profile. At the same time, soft tissue has some independence. However, the exact quantitative relationship remains to be further studied.

Simulation on the Comparison of Steady-State Responses Synthesized by Transient Templates Based on Superposition Hypothesis.

The generation of auditory-evoked steady-state responses (SSRs) is associated with the linear superposition of transient auditory-evoked potentials (AEPs) that cannot be directly observed. A straightforward way to justify the superposition hypothesis is the use of synthesized SSRs by a transient AEP under a predefined condition based on the forward process of this hypothesis. However, little is known about the inverse relation between the transient AEP and its synthetic SSR, which makes the interpretation of the latter less convincible because it may not necessarily underlie the true solution. In this study, we chose two pairs of AEPs from the conventional and deconvolution paradigms, which represent the homo-AEPs from a homogenous group and the hetero-AEPs from two heterogeneous groups. Both pairs of AEPs were used as templates to synthesize SSRs at rates of 20-120 Hz. The peak-peak amplitudes and the differences between the paired waves were measured. Although amplitude enhancement occurred at ~40 Hz, comparisons between the available waves demonstrated that the relative differences of the synthetic SSRs could be dramatically larger at other rates. Moreover, two virtually identical SSRs may come from clearly different AEPs. These results suggested inconsistent relationships between the AEPs and their corresponding SSRs over the tested rates.

[Development of a visualization system for minimally invasive surgical abortion].

This article introduces the principle, structure and components of a visualization system for carrying out minimally invasive surgical abortion. Without altering the current surgical approach or increasing the surgical difficulty, the surgical system integrated a mini-CMOS image sensor and LED light and a visual device to allow fixed-point removal of the fetus or embryo in the minimally invasive surgery.

[A new algorithm for magnetic resonance image segmentation based on fuzzy kerne1 clustering].

OBJECTIVE: Fuzzy clustering technique is a popular model widely used in the segmentation of magnetic resonance (MR) images. However, when the conventional fuzzy clustering algorithm is used for image segmentation, the algorithm strictly depending on the current pixels works only on images with less noise. In the paper, we presented a modified fuzzy kernel clustering algorithm for MR image segmentation. The new algorithm incorporates a kernel-induced distance mertric and a penalty term that controls the neighborhood effect to the objective function. The results of experiment on both the synthetic images and simulated MR images show that the proposed algorithm is more robust to noise than the standard fuzzy image segmentation algorithms.

[Invert transformer design for high frequency X-ray machine based on PWM controller SG 3525].

This paper introduces the principle of invert transformer of high frequency X-ray machine, and analyzes its main constitution. Meanwhile, a scheme based on SG3525 for closed loop voltage regulation is given. The experimental result testifies its efficiency and utility.