NPF transporters in synaptic-like vesicles control delivery of iron and copper to seeds.

Accumulation of iron in seeds is essential for both plant reproduction and human nutrition. Transport of iron to seeds requires the chelator nicotianamine (NA) to prevent its precipitation in the plant vascular tissues. However, how NA is transported to the apoplast for forming metal-NA complexes remains unknown. Here, we report that two members of the nitrate/peptide transporter family, NAET1 and NAET2, function as NA transporters required for translocation of both iron and copper to seeds. We show that NAET1 and NAET2 are predominantly expressed in the shoot and root vascular tissues and mediate secretion of NA out of the cells in resembling the release of neurotransmitters from animal synaptic vesicles. These findings reveal an unusual mechanism of transmembrane transport in plants and uncover a fundamental aspect of plant nutrition that has implications for improving food nutrition and human health.

Risk factors of acute coagulation dysfunction after aneurysmal subarachnoid hemorrhage.

BACKGROUND: Although coagulopathy have been proved to be a contributor to a poor outcome of aneurysmal subarachnoid hemorrhage (aSAH), the risk factors for triggering coagulation abnormalities have not been studied after aneurysm clipping. METHODS: We investigated risk factors of coagulopathy and analyzed the relationship between acute coagulopathy and outcome after aneurysm clipping. The clinical data of 137 patients with ruptured CA admitted to our institution was collected and retrospectively reviewed. Patient demographic data (age, sex), smoking, alcohol use, hypertension, diabetes, Hunt-Hess grade, Fisher grade, operation time, intraoperative total infusion volume, intraoperative blood loss, intraoperative transfusion, intraoperative hemostatic drug treatment, calcium reduction (preoperative free calcium concentration-postoperative free calcium concentration) were recorded. Coagulation was assessed within 24 h. Postoperative hemorrhage and infarction, deep venous thrombosis (DVT), and mortality were analyzed. RESULTS: Coagulopathy was detected in a total of 51 cases (group I), while not in 86 cases (group II). Univariable analysis demonstrated that age, smoking, alcohol use, intraoperative total infusion volume, intraoperative blood loss, intraoperative transfusion, and calcium reduction (≥ 1.2 mg/dl) were related to coagulopathy. Non-conditional logistic regression analysis showed that age [OR, 1.037 (95% CI, 1.001-1.074); p = 0.045] and calcium reduction (≥ 1.2 mg/dl) [OR, 5.509 (95% CI, 1.900-15.971); p = 0.002] were considered as the risk factors for coagulopathy. Hunt-Hess grade [OR, 2.641 (95% CI, 1.079-6.331); p = 0.033] and operation time [OR, 0.107 (95% CI, 1.012-0.928); p = 0.043] were considered as the risk factors for hypocoagulopathy. There were 6 cases (11.7%) with cerebral infarction in group I, while 6 cases (6.98%) in group II (χ 2 = 0.918, p = 0.338). There were 4 cases (7.84%) with rebleeding in group I, while 5 cases (5.81%) in group II (χ 2 = 0.215, p = 0.643). The mortality was 9.80% (5/51) in group I, while 1.16% (1/86) in group II (χ 2 = 5.708, p = 0.017). DVT was not detected in all cases. CONCLUSIONS: In conclusion, age (≥ 65 years) and calcium reduction (≥ 1.2 mg/dl) were considered as the risk factors for coagulopathy and have been proved to be associated with higher mortality after aneurysm clipping.