Abnormal lipid metabolism down‐regulates adenosine triphosphate synthase β‐subunit protein expression in corpus cavernosum smooth muscle in vitro and in vivo

Metabolic syndrome is closely related to erectile dysfunction (ED), and hyperlipidaemia is considered a major risk factor for ED. Adenosine triphosphate (ATP) synthase is believed to play an important role in metabolic syndrome; it has been hypothesised that ATP synthase contributes to ED development. We have verified this hypothesis using primary cultured human corpus cavernosum smooth muscle (HCCSM) cells treated with excessive free fat acid (FFA) and a high‐fat diet (HFD) mouse model. Our results showed that high fatty factors could cause lipid accumulation in HCCSM cells, which could result in abnormal lipid metabolism, such as high levels of triglycerides, cholesterol and glucose in the HFD mice. There was a remarkable down‐regulation of ATP synthase and p‐Akt after in vivo and in vitro excessive FFA treatments. These results indicated that abnormal lipid metabolism could induce ATP synthase down‐regulation via the Akt phosphorylation pathway and that ATP synthase may be a target of lipotoxicity in corpus cavernosum smooth muscle cells.     

Diagnostic accuracy of CBCT for periodontal lesions

Objectives

The present study compares the diagnostic value of periodontal bone defect images using conventional two-dimensional single-tooth radiographs and three-dimensional cone beam computed tomography (CBCT) images.

Materials and methods

Classified periodontal bone defects were prepared on pig mandibles and presented radiographically. Fifteen dentists were instructed to make a diagnosis based on these x-rays, regarding the type and the extent of the bone defects. Subsequently, the results were evaluated and compared to the morphology of the surgically prepared defects as the gold standard.

Results

On average, the diagnosis of infrabony defects were 21 %, dehiscence 25 %, and fenestration 33 % more accurate using the three-dimensional projection than with the single-tooth radiograph. Furthermore, the CBCT allows grade II furcation to be captured more accurately.

Conclusions

The results of this study indicate that a considerably more precise analysis of periodontal defects is possible due to the third dimension. Particularly, in the oro-vestibular orientation, defects could be detected significantly more accurate.

Clinical relevance

CBCT images offer an advantageous alternative to the conventional single-tooth radiograph while taking the higher exposure of radiation into account.     

Crystallization and preliminary X‐ray diffraction analysis of eukaryotic α2‐macroglobulin family members modified by methylamine,proteases and glycosidases

α₂‐Macroglobulin (α₂M) has many functions in vertebrate physiology. To understand the basis of such functions, high‐resolution structural models of its conformations and complexes with interacting partners are required. In an attempt to grow crystals that diffract to high or medium resolution, we isolated native human α₂M (hα₂M) and its counterpart from chicken egg white (ovostatin) from natural sources. We developed specific purification protocols, and modified the purified proteins either by deglycosylation or by conversion to their induced forms. Native proteins yielded macroscopically disordered crystals or crystals only diffracting to very low resolution (>20 Å), respectively. Optimization of native hα₂M crystals by varying chemical conditions was unsuccessful, while dehydration of native ovostatin crystals improved diffraction only slightly (10 Å). Moreover, treatment with several glycosidases hindered crystallization. Both proteins formed spherulites that were unsuitable for X‐ray analysis, owing to a reduction of protein stability or an increase in sample heterogeneity. In contrast, transforming the native proteins to their induced forms by reaction either with methylamine or with peptidases (thermolysin and chymotrypsin) rendered well‐shaped crystals routinely diffracting below 7 Å in a reproducible manner.