Effects of extracts from Gynura bicolor (Roxb. & Willd.) DC. on iron bioavailability in rats

Gynura bicolor (Roxb. & Willd.) DC. is widely distributed in certain areas of Asia and is very popular in vegetarian cuisine in Taiwan. This study investigates the effects of G. bicolor extracts with different polarities of 80 mg/kg body weight (BW) G. bicolor alcohol extract, 80 mg/kg BW G. bicolor water extract, and 80 mg/kg BW G. bicolor ether extract on Fe bioavailability using the hemoglobin repletion efficiency assay. Wistar rats were assigned to five groups: a group receiving an iron-deficient (ID) diet; a group receiving an ID diet supplemented with ferrous sulfate (20 mg Fe/kg BW); and three groups receiving ID diets supplemented with ferrous sulfate and one of G. bicolor alcohol extract, G. bicolor water extract, or G. bicolor water extract. The results indicated that the levels of hemoglobin, serum iron, serum ferritin, liver ferritin, hemoglobin regeneration efficiency, relative biological value, and hepcidin all were significantly higher than those of the ID diet group. Besides, the iron transporter divalent metal transporter-1 was significantly reduced, but iron release protein expression of ferroportin was significantly increased. It was concluded that G. bicolor extracts may promote iron bioavailability and regulate the expressions of divalent metal transporter-1 and ferroportin.     

Endoscopic vacuum-assisted closure of upper intestinal anastomotic leaks

BACKGROUND: Management of intrathoracic anastomotic leaks remains an interdisciplinary challenge. Established treatment options include percutaneous drainage, endoscopic closure, or even surgical revision. All these procedures are associated with high morbidity and mortality rates. OBJECTIVE: We report a new, effective endoscopic treatment option for intrathoracic esophageal anastomotic leaks by using an endoscopic vacuum-assisted closure system. PATIENTS: Two patients with intrathoracic anastomotic leaks after esophagectomy and gastrectomy were included. METHODS: Surgical reinterventions failed to seal the leaks in 1 patient, whereas in the other patient the anastomotic leakage persisted after endoscopic placement of 2 covered self-expanding metal stents. We endoscopically placed transnasal draining tubes that were armed with a size-adjusted sponge at their distal tip in the necrotic anastomotic cavities. Continuous suction was applied. Sponge and drain were changed twice a week. RESULTS: No complications were noted during the course of treatment. After a median of 15 days, closure of the wound cavities was achieved in all cases. A median of 5 endoscopic interventions was necessary. Both patients returned gradually to a solid diet without recurrence of the leaks. CONCLUSION: Endoscopic vacuum-assisted closure might be an effective alternative in the treatment of upper intestinal anastomotic leaks.     

金属覆膜支架联合鼻胆管治疗内镜逆行胰胆管造影术Ⅲ型Stapfer穿孔的研究（附6例报告）

目的总结金属覆膜支架联合鼻胆管治疗内镜逆行胰胆管造影术(ERCP)Ⅲ型Stapfer穿孔的疗效及安全性。方法对ERCPⅢ型Stapfer穿孔患者放置金属覆膜胆道支架,支架内再放置鼻胆引流管,术后2~4周行支架取出术。结果 6例患者均好转出院,无开腹手术患者,有效率100.00%,无支架相关并发症发生。1例住院期间出现腹腔感染症状,发生率为16.67%。结论金属覆膜支架联合鼻胆管治疗ERCPⅢ型Stapfer穿孔的方法是安全有效的,值得临床推广应用。     

Heat-assisted slurry sampling GFAAS method for determination of lead in food standard reference materials

A valid method based on heat-assisted slurry sampling graphic furnace atomic absorption spectrometry (HASS-GFAAS) was developed for the accurate determination of trace Pb in food standard reference materials (SRMs). The HASS technique significantly improved Pb recovery and precision compared to conventional slurry sampling techniques. The optimized HASS procedure was performed as follows: first, the sample (particle size ≤ 150 μm) was diluted with 0.05% (v/v) Triton X-100 containing 2% HNO₃ and 1% H₂O₂ followed by heating for 20 min at 120 °C on a heating block. Next, the obtained slurry was sonicated in an autosampler cup, and finally, the slurry was introduced into a graphite tube and analyzed by the GFAAS with a Pb electrodeless discharge lamp (EDL). Calibration with aqueous standard solutions was used for Pb determination in food samples. The characteristic mass and limit of detection for Pb based on the integrated absorbance for a 2% (m/v) sample were 12 ± 0.6 pg and 0.003 mg kg⁻¹, respectively. The accuracy (95.1–102% recovery) and good precision (0.1–3.6%) of this procedure are illustrated by the results obtained for the 12 food reference materials. The proposed method is suitable for determination of trace Pb in solid food samples.     

Toxic trace elements at gastrointestinal level

Many trace elements are considered essential [iron (Fe), zinc (Zn), copper (Cu)], whereas others may be harmful [lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As)], depending on their concentration and chemical form. In most cases, the diet is the main pathway by which they enter our organism. The presence of toxic trace elements in food has been known for a long time, and many of the food matrices that carry them have been identified. This has led to the appearance of legislation and recommendations concerning consumption. Given that the main route of exposure is oral, passage through the gastrointestinal tract plays a fundamental role in their entry into the organism, where they exert their toxic effect. Although the digestive system can be considered to be of crucial importance in their toxicity, in most cases we do not know the events that occur during the passage of these elements through the gastrointestinal tract and of ascertaining whether they may have some kind of toxic effect on it. The aim of this review is to summarize available information on this subject, concentrating on the toxic trace elements that are of greatest interest for organizations concerned with food safety and health: Pb, Cd, Hg and As.     

铁超载与脑出血后脑损伤

脑出血(intracerebral hemorrhage,ICH)是一种常见神经系统疾病,其死亡率和致残率均很高,但目前对ICH后脑损伤的机制尚未完全阐明.最新的研究表明,铁超载在ICH后脑损伤中起着重要作用.文章对脑铁分布和功能、ICH后铁超载引起脑损伤的机制以及铁螯合剂应用等方面的研究进展进行了综述.     

可膨式金属胆道支架解除恶性胆管梗阻的中长期疗效

为总结经内镜放置可膨式金属胆道支架（ＥＭＢＥ）的中远期疗效，回顾了７６例恶性胆管梗阻接受ＥＭＢＥ治疗患者的资料，并与同期５３例次放置普通塑料支架的疗效进行对比。结果前者操作成功率９３．８％，与操作有关的并发症发生率６．６％，黄疸消除率为８７．０％，金属支架的平均通畅期为３１０天，明显高于塑料支架的８５天（Ｐ＜０．０１），患者平均存活期为２１０天。随访患者中有１６例（３４．８％）发生支架阻塞，平均发生时间１８５．５天。结果表明可膨式金属胆道支架的平均通畅性能显著优于普通塑料支架，可持久有效解除恶性肿瘤所致的肝外胆管梗阻，为提高ＥＭＢＥ的疗效必须严格掌握适应证     

Dematin,a human erythrocyte cytoskeletal protein,is a substrate for a recombinant FIKK kinase from Plasmodium falciparum

P. falciparum causes the most deadly form of malaria, resulting from the adherence of infected red blood cells to blood vessels. During the blood stage of infection, the parasite secretes a large number of proteins into the host erythrocyte. The secretion of a 20-member family of protein kinases known as FIKK kinases, after a conserved Phe-Ile-Lys-Lys sequence motif, is unique to P. falciparum. Identification of physiological substrates of these kinases may provide perspective on the importance of FIKK kinase activity to P. falciparum virulence. We demonstrate, for the first time, the heterologous expression and purification of a FIKK kinase (PfFk4.1, PFD1165w). The recombinant kinase is active against general substrates and phosphorylates itself. Having demonstrated kinase activity, we incubated recombinant Fk4.1 with parasite and human erythrocyte lysates. No parasite-derived substrates were identified. However, treatment of erythrocyte ghosts shows that the FIKK kinase Fk4.1 phosphorylates dematin, a cytoskeletal protein found at the red blood cell spectrin–actin junction.     

Lead and Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms: A meta-analysis

This meta-analysis examined the association between Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms and lead exposure in children and adolescents. Thirty-three studies published between 1972 and 2010 involving 10,232 children and adolescents were included. There was a small to medium association between inattention symptoms and lead exposure (r = .16, k = 27, p < .001) and a similar association between hyperactivity/impulsivity symptoms and lead exposure (r = .13, k = 23, p < .001). There was significant heterogeneity among the effect sizes for both inattention symptoms and for hyperactivity/impulsivity symptoms, with studies using hair analysis to assess lead burden yielding substantially larger effect sizes than those using other methods. Excluding the hair analysis studies, the average rs were .14 for inattention (k = 23, p < .001) and .12 for hyperactivity/impulsivity (k = 21, p < .001). Overall, the relation between lead exposure and ADHD symptoms was similar in magnitude to the relation between lead exposure and decreased IQ and between lead exposure and conduct problems.     

Ruthenium Ring‐Opening Metathesis Polymerization Catalysts Bearing o‐ Aryloxide‐N‐Heterocyclic Carbenes

A series of o‐aryloxide‐N‐heterocyclic carbene ruthenium complexes 2–4 is synthesized via sequential reactions of the o‐hydroxyaryl imidazolium proligands (2‐OH‐3,5‐^tBu₂C₆H₂)(R)(C₃H₃N₂)⁺Br^? (R = Me ( 1a ), ⁱPr ( 1b ), Mes ( 1c )) with Ag₂O and [(C₆H₆)RuCl₂]₂. All of the complexes are characterized by ¹H and ¹³C NMR spectroscopy, high‐resolution mass spectrometry (HRMS), and elemental analysis. The molecular structure of 2 is determined by single‐crystal X‐ray diffraction analysis. The ring‐opening metathesis polymerization (ROMP) of norbornene (NBE) with 2 – 4 is studied. Among them, complex 4 exhibits the highest activity and efficiency toward ROMP of NBE at 85 °C without any cocatalyst, and the resultant polymers have very high molecular weight (>10⁶ Da) and narrow molecular weight distributions. This complex can also efficiently catalyze the alternating copolymerization of NBE and cyclooctene.