Modified maxillomandibular advancement for obstructive sleep apnoea: towards a better outcome for Asians.

Excluding tracheostomy, maxillomandibular advancement (MMA) is the most effective surgical treatment for obstructive sleep apnoea (OSA). However, the anticipated facial changes may prevent acceptance of this procedure by patients with bimaxillary protrusion, a common feature of Asian faces. We therefore developed a modified MMA technique for such cases, consisting of anterior segmental osteotomies together with standard Le Fort I and bilateral sagittal split osteotomies. A prospective study of 20 consecutive Taiwanese adults with moderate-to-severe OSA who underwent modified MMA and postsurgical orthodontics was undertaken to evaluate the efficacy with regard to OSA and the postoperative facial appearance and dental occlusion. After modified MMA, the mean apnoea-hypopnoea index decreased from 41.6±19.2 n/h to 5.3±4.0 n/h (P<0.001). All patients had a successful outcome. No patient was dissatisfied with their postoperative facial appearance. The mean Peer Assessment Rating score decreased from 21.9±14.3 to 1.7±1.6 (P=0.001). The data suggest that the modified MMA is effective in treating patients with moderate-to-severe OSA without negatively affecting facial appearance or dental occlusion. To achieve a better outcome, surgical-orthodontic integration is warranted. The surgery-first approach can achieve early improvement.

Do glial cells play an anti-oxidative role in Huntington's disease?

Oxidative stress is a condition of imbalance between reactive oxygen species (ROS) formation and antioxidant capacity as a result of dysfunction of the antioxidant system. ROS can be served as a second messenger at low or moderate concentration, while excessive amount of ROS under oxidative stress condition would destroy macromolecules like proteins, DNA, and lipids, finally leading to cell apoptosis or necrosis. Changes in these macromolecules are involved in various pathological changes and progression of diseases, especially neurodegenerative diseases. Neurodegenerative diseases are morphologically featured by progressive neuronal cell loss, accompanied with inclusions formed by protein aggregates in neurons or glial cells. Neurons have always received much more attention than glial cells in neurodegenerative diseases. Actually, glial cells might play a key role in the functioning of neurons and cellular survival through an antioxidant way. Additionally, neurons can modulate the activities of glia either. Herein, the main purposes of this review are to mention the connection between Huntington's disease (HD) and oxidative stress, to summarize the characteristics and functions of glial cells in HD, to state the cross talk between neurons and glial cells, and to emphasize the conclusive role of activation of Keap1-Nrf2-ARE pathway in glial cells against oxidative stress in HD.

Glucosamine induces activated T cell apoptosis through reduced T cell receptor.

Glucosamine (GlcN), like N-acetylglucosamine (GlcNAc), is salvaged into the hexosamine pathway and is converted to UDP-GlcNAc. Golgi N-glycan branching enzymes produce N-glycans, using UDP-GlcNAc as a substrate, which attach to the T cell receptor (TCR) and cytotoxic T-lymphocyte antigen-4 (CTLA-4). These findings suggest that GlcN exerts the immunoregulation through TCR signalling, which could be involved not only in cytokine production but also activated T cell apoptosis. In fact, a preliminary study showed that GlcN reduced the number of CD3+ T cells of NC/Nga mice with AD-like skin lesions. Therefore, whether apoptosis of T cells would be one of the potential molecular mechanisms of GlcN-induced immunosuppression was investigated. Cultured human primary along with Jurkat T cells and purified T cells from NC/Nga mice with or without Df-induced AD-like skin lesion were used for the study. Glucosamine treatment increased the number of T cells expressing ß1,6GlcNAc-branched N-glycans, with reduced ZAP-70 phosphorylation and enhanced CTLA-4 expression. Glucosamine treatment reduced the number of activated T cells from both the human primary and Jurkat cells and the dermatitis-induced mice. The expression of FasL and activated caspases, particularly caspase-3, was increased, whereas the phosphorylation of PI3K, Akt and NF-κB was decreased by GlcN treatment. Therefore, in addition to down-regulating TCR signalling and promoting CTLA-4 expression, GlcN may also suppress T cell function by enhancing apoptosis of activated T cells, through both extrinsic and intrinsic apoptotic signalling pathways, which were regulated by the inhibition of PI3K/Akt and NF-κB phosphorylation.

Occurrence and distribution of Naegleria species from thermal spring environments in Taiwan.

UNLABELLED: Naegleria spp. is a free-living amoeba that can be found in the natural environment. A number of Naegleria spp. can cause fatal infections in the central nervous system in humans and animals, and the most important source of infection is through direct water contact. In this study, water samples from various thermal springs were taken from four thermal spring areas. Naegleria spp. was detected via culture confirmation and molecular taxonomic identification. Among the 60 samples obtained, Naegleria spp. was identified in 26 (43·3%) samples. The identified species included Naegleria australiensis, Naegleria gruberi, Naegleria lovaniensis and Naegleria mexicana. The presence of living Naegleria spp. was significantly associated with elevated pH value in the water sample. SIGNIFICANCE AND IMPACT OF STUDY: In this study, we examined the presence of living Naegleria spp. in thermal spring waters in south-eastern Taiwan. Naegleria spp. was isolated and culture-confirmed from thermal spring water. Naegleria fowleri was not found in all water samples, and Naegleria australiensis was the most common Naegleria genotype.

Protopanaxatriol metabolites identified by LC-MS/MS after oral administration in mice.

OBJECTIVE: 20(S)-Protopanaxatriol (Ppt), a well-known end metabolite of protopanaxatriol-type saponins, has recently been reported to have the same bioactivity as its prototype. Whether or not Ppt could be further metabolized into other compounds in vivo is still unknown. The present study is aimed to determine the structures of Ppt metabolites in mice. MATERIALS: The metabolites were produced by intragastric gavage of Ppt in mice. The homogenate of small intestine was used for analysis after solid phase extraction. METHODS: The metabolic profile of Ppt was investigated by using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), which were also used to identify the structures of metabolites. Accurate mass measurement using LC-time of flight MS was applied to determine the element composition of metabolites and thus to confirm their proposed structures. RESULTS: One Phase I and three Phase II metabolites were detected at 1 h, 5 h, and 10 h after administration of Ppt, which were the same at the three time points. The Phase I metabolic changes observed included dehydrogenation and hydroxylation of the steroid-like structure, as well as formation of an ester bond at C-20 of the side chain. The Phase II metabolites involved conjugation to aminoethylsulfonic acid after hydrolysis of the ester bond. A possible biotransformation pathway was proposed. CONCLUSIONS: Ppt yielded four metabolites in vivo, and 1 h was enough to complete the biotransformation process of Ppt.