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Background
Iron metabolism during pregnancy maintains fetal iron levels at the expense of the mother. The mechanism behind this regulation is still not clear despite recent advances. Here we examine the role of maternal and fetal Hfe, its downstream signaling molecule, hepcidin and dietary iron in the regulation of placental iron transfer.Design and Methods
Hfe wild-type, knockout and heterozygote dams were fed iron deficient (12.5 ppm), adequate (50 ppm) and replete (150 ppm) iron diets and mated with heterozygote males to produce pups of all genotypes. Dams and pups were sacrificed at Day 18 of gestation; serum, placenta, body and liver iron parameters were measured. Protein and mRNA levels of various iron transporter genes were determined in duodenum, liver and placenta by Western blotting and real time PCR.Results
Maternal liver iron levels were dependent on both dietary iron intake and Hfe genotype. Increasing iron levels in the maternal diet resulted in increased total iron in the fetus, primarily in the liver. However, fetuses of Hfe-knockout mothers showed further elevation of liver iron levels, concomitant with elevated expression of Tfr1, Dmt1 and Fpn in the placenta. Hfe-knockout fetuses that express low levels of liver hepcidin accumulated more iron in their liver than wild-type fetuses due to increased ferroportin levels in the placenta.Conclusions
Maternal and fetal status, as well as dietary iron, is important in regulating iron transfer across placenta. Maternal Hfe regulates iron transfer by altering gene expression in the placenta. Fetal Hfe is important in regulating placental iron transfer by modulating fetal liver hepcidin expression. 相似文献85.
Michele Raja Antonella Azzoni 《International journal of psychiatry in clinical practice》2013,17(2):146-148
Objective. To point out the danger of worsening mood disorders with the use of hypericum. Methods. Longitudinal clinical observation of two cases treated with hypericum. Results. The two patients underwent mixed episodes following hypericum treatment. One of them needed hospitalization for suicidal risk. Conclusion. Caution is warranted in the use of hypericum in depressed patients with hidden bipolarity. Patients should be informed that hypericum may induce manic symptoms, increase cycling of mood states, or worsen the depressive state. 相似文献
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R. V. Kishore Kumar Sathya Kumar Devireddy Raja Sekhar Gali Nemaly Chaithanyaa Sridhar 《Journal of maxillofacial and oral surgery》2013,12(1):21-29
Introduction
Injuries of the facial soft tissues may be due to road traffic accidents, industrial injuries, domestic and interpersonal violence, dog bites, human bites, war injuries etc. They may be described depending on the depth of involvement of the soft tissue and/or region since it gives the clinician the method of treatment. The soft tissue injuries must take into the underlying skeletal injury into account since these injuries if carelessly handled they leave deformed scarring in the most precious and beautiful part of the body.Materials and Methods
Various patients reporting to the department of Oral and Maxillofacial Surgery, Narayana Dental College and hospital, Nellore were included in the study. Injuries in the various aspects of face at various anatomical areas has been presented with the mode of management.Conclusion
The maxillofacial surgeon while attending these cases should avoid the need for revision by having a thorough knowledge of the anatomy, physiology of the soft tissues and treat them accordingly after following good clinical and radiological examination. 相似文献87.
Raja KalayarasanAmit Javed M.S. M.Ch. Puja SakhujaAnil K. Agarwal M.S. M.Ch. 《American journal of surgery》2013
Background
Literature on squamous variants of gallbladder cancer (GBC) is limited.Methods
This was a retrospective analysis of GBC patients operated on between August 2009 and March 2012. Patients with adenosquamous carcinoma or squamous cell carcinoma were compared with adenocarcinoma for clinicopathologic features and surgical outcomes.Results
Of the primary GBC patients resected with curative intent, 14 had adenosquamous carcinoma (10) or squamous cell carcinoma (4) (group A), whereas 122 had adenocarcinoma (group B). Abdominal pain was the most common symptom in both groups; however, presentation with vomiting and an abdominal lump was more common in group A (P = .04 and <.01, respectively). Group A had a significantly larger tumor size (7.9 vs 4.8 cm, P = .01) and a higher incidence of adjacent organ involvement requiring extended resections (85.7% vs 26.2%, P < .01). Despite the higher T stage, node-negative disease was significantly higher in group A (42.9% vs 17.2%, P = .03). There was no significant difference in the median survival after curative resection between the 2 groups (28 vs 31 months, P = .24).Conclusions
The squamous variant of GBC presented at an advanced T stage; however, nodal involvement and distant metastasis were less common. Despite the higher T stage, curative resection could be achieved in the majority with a comparable survival. 相似文献88.
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A Besarab SN Zeig ER Martin PE Pergola FC Whittier RI Zabaneh B Schiller M Mayo CA Francisco KR Polu AM Duliege 《BMC nephrology》2012,13(1):95
ABSTRACT: BACKGROUND: Peginesatide is a peptide-based erythropoiesis-stimulating agent that was designed and engineered to stimulate specifically the erythropoietin receptor dimer that governs erythropoiesis. The primary objective of this phase 2 dose-finding study was to determine the once-monthly peginesatide dosing strategy that would maintain hemoglobin within [PLUS-MINUS SIGN]1.0 g/dL of baseline values after conversion from epoetin alfa; the safety of peginesatide was evaluated concurrently. METHODS: Chronic hemodialysis patients on stable regimens of epoetin alfa were sequentially assigned to cohorts that differed on (1) how the peginesatide starting dose was determined (using a single epoetin alfa--to-peginesatide dose conversion ratio or a tiered, weight-based or absolute-dose conversion table) and on (2) whether or not a 1-week erythropoiesis-stimulating agent-free interval was used. Peginesatide doses were titrated to maintain hemoglobin levels within [PLUS-MINUS SIGN]1.0 g/dL from baseline. RESULTS: A total of 164 patients were enrolled and received intravenous peginesatide every 4 weeks for up to 6 doses; the duration of the study including follow-up was [LESS-THAN OR EQUAL TO]29 weeks. Overall, the proportion of patients with hemoglobin levels within [PLUS-MINUS SIGN]1.0 g/dL of baseline increased over the course of the study from 39% (Weeks 2--13) to 54% (Weeks 18--25). Cohorts that used tiered dose conversion tables trended towards having more stable peginesatide doses than did those cohorts that used a single dose conversion ratio. Moreover, cohorts that used an erythropoiesis-stimulating agent-free interval did not have the substantial initial increase in hemoglobin levels that was seen in those cohorts that did not use such an interval. In this study, the safety profile of peginesatide was consistent with those of marketed erythropoiesis-stimulating agents. CONCLUSIONS: The results of this study were used to guide the dosing regimens used subsequently in phase 3 studies. Once-monthly peginesatide is feasible in hemodialysis patients.Trial registrationClinicalTrials.gov registration: NCT00228449. 相似文献