Endoscopic treatment for gastric antral vascular ectasia.

Gastric antral vascular ectasia (GAVE) is one of the uncommon causes of upper gastrointestinal bleeding. Major treatment of GAVE includes pharmacotherapy, endoscopy, and surgery. The efficacy and safety of pharmacotherapy have not been sufficiently confirmed; and surgery is just considered when conservative treatment is ineffective. By comparison, endoscopy is a common treatment option for GAVE. This paper reviews the currently used endoscopic approaches for GAVE, mainly including argon plasma coagulation (APC), radiofrequency ablation (RFA), and endoscopic band ligation (EBL). It also summarizes their efficacy and procedure-related adverse events. The endoscopic success rate of APC is 40-100%; however, APC needs several treatment sessions, with a high recurrence rate of 10-78.9%. The endoscopic success rates of RFA and EBL are 90-100% and 77.8-100%, respectively; and their recurrence rates are 21.4-33.3% and 8.3-48.1%, respectively. Hyperplastic gastric polyps and sepsis are major adverse events of APC and RFA; and Mallory-Weiss syndrome is occasionally observed after APC. Adverse events of EBL are rare and mild, such as nausea, vomiting, esophageal or abdominal pain, and hyperplastic polyps. APC is often considered as the first-line choice of endoscopic treatment for GAVE. RFA and EBL have been increasingly used as alternatives in patients with refractory GAVE. A high recurrence of GAVE after endoscopic treatment should be fully recognized and cautiously managed by follow-up endoscopy. In future, a head-to-head comparison of different endoscopic approaches for GAVE is warranted.

Attitudes Toward Advance Directives Among Patients and Their Family Members in China.

OBJECTIVES: Chinese people are generally unfamiliar with the concept of advance care planning or advance directives (ACP/ADs), which raises dilemmas in life-support choice and can even affect clinical decision making. To understand and address the issues involved better, we investigated the awareness of ACP/ADs in China, as well as people's attitudes toward medical autonomy and end-of-life care. DESIGN: A multicenter cross-sectional survey, conducted from August 1 to December 31, 2016. SETTING: Twenty-five hospitals located in 15 different provinces throughout mainland China. PARTICIPANTS: Pairs of adult patients without dementia or malignancies, and a family member. MEASUREMENTS: Participants self-filled anonymous questionnaires, and the data collected were analyzed to relate patients' sociodemographic characteristics to their awareness of ACP/ADs and attitudes to health care autonomy and end-of-life care. RESULTS: Among 1084 patients who completed the questionnaire, 415 (38.3%) had heard about ACP/ADs. Having been informed about ACP/ADs, 995 (91.8%) were willing to find out their true health status and decide for themselves; 549 (50.6%) wanted to institute ACP/ADs. Regarding end-of-life care, 473 (43.6%) chose Do Not Resuscitate, and 435 (40.1%) wished to forgo life-support treatment if irreversibly moribund. Patients predominantly (481, 44.4%) chose general hospital as their preferred place to spend their last days of life; only 114 (10.5%) favored a special hospice facility. Patients' main concerns during end-of-life care were symptom control (35.1%), followed by functional maintenance and quality of life (29.8%), and prolonging life (18.9%). More highly educated patients had significantly greater awareness of ACP/ADs than less well educated ones (χ2 = 59.22, P < .001) and were more willing to find out the truth for themselves (χ2 = 58.30, P ≤ .001) and make medical decisions in advance (χ2 = 55.92, P < .001). Younger patients were also more willing than older ones to know the truth (χ2 = 38.23, P = .001) and make medical decisions in advance (χ2 = 18.42, P = .018), and were also more likely to wish to die at home (χ2 = 96.25, P < .001). Only 212 patients' family members (19.6%) wanted life-support treatment for themselves if irreversibly moribund, whereas 592 (54.6%) would want their relative to receive such procedures in the same circumstances; a similar discrepancy was evident for end-of-life invasive treatment (18.3% vs 42.7%). CONCLUSIONS: Awareness about ACP/ADs in China is still low. Providing culturally sensitive knowledge, education, and communication regarding ACP/ADs is a feasible first step to promoting this sociomedical practice.

High-dose insulin inhibits gap junction intercellular communication in vascular smooth muscle cells.

Gap junction intercellular communication (GJIC) is important in mediating intercellular substance and signal transmission. Connexin (Cx)43 is a major component involved in GJIC in vascular tissue and its abnormal expression is closely associated with various vascular diseases. Insulin resistance is the central component of metabolic syndrome, and high doses of insulin can affect vascular function through multiple pathways, resulting in cardiovascular disease. However, the effects of insulin on GJIC function and connexin (Cx)43 expression in vascular smooth muscle cells (VSMCs) remain unclear. Following treatment of VSMCs with different doses of insulin, a fluorescence recovery after photobleaching (FRAP) assay was performed to evaluate GJIC function in treated VSMCs. The results showed that high­dose insulin suppressed GJIC function. Western blot assays further demonstrated that high­dose insulin induced the phosphorylation of Cx43 at s368 and downregulated the expression of Cx43. H2O2 release assays demonstrated that high­dose insulin treatment significantly elevated the cellular H2O2 level. In addition, compared with cells treated with high­dose insulin, pretreatment with catalase significantly restored the cellular GJIC function, decreased the phosphorylation level of Cx43 at s368, and enhanced Cx43 expression. In conclusion, these data indicate that high­dose insulin inhibits cellular GJIC function through the oxidative stress­activated signaling pathway. This phenomenon may also constitute a potential mechanism underlying the pathogenesis of insulin resistance and its complications.

A novel medical image protection scheme using a 3-dimensional chaotic system.

Recently, great concerns have been raised regarding the issue of medical image protection due to the increasing demand for telemedicine services, especially the teleradiology service. To meet this challenge, a novel chaos-based approach is suggested in this paper. To address the security and efficiency problems encountered by many existing permutation-diffusion type image ciphers, the new scheme utilizes a single 3D chaotic system, Chen's chaotic system, for both permutation and diffusion. In the permutation stage, we introduce a novel shuffling mechanism, which shuffles each pixel in the plain image by swapping it with another pixel chosen by two of the three state variables of Chen's chaotic system. The remaining variable is used for quantification of pseudorandom keystream for diffusion. Moreover, the selection of state variables is controlled by plain pixel, which enhances the security against known/chosen-plaintext attack. Thorough experimental tests are carried out and the results indicate that the proposed scheme provides an effective and efficient way for real-time secure medical image transmission over public networks.