Effect of iron deficiency without anaemia on days alive and out of hospital in patients undergoing valvular heart surgery

Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml^-1 or < 300 ng.ml^-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l^-1, 143 (133–150 [120–179]) g.l^-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.     

Goal-directed fluid removal with furosemide versus placebo in intensive care patients with fluid overload: A randomised,blinded trial (GODIF trial—First version)

Background

Salt and water accumulation leading to fluid overload is associated with increased mortality in intensive care unit (ICU) patients, but diuretics' effects on patient outcomes are uncertain. In this first version of the GODIF trial, we aimed to assess the effects of goal-directed fluid removal with furosemide versus placebo in adult ICU patients with fluid overload.

Methods

We conducted a multicentre, randomised, stratified, parallel-group, blinded, placebo-controlled trial in clinically stable, adult ICU patients with at least 5% fluid overload. Participants were randomised to furosemide versus placebo infusion aiming at achieving neutral cumulative fluid balance as soon as possible. The primary outcome was the number of days alive and out of the hospital at 90 days.

Results

The trial was terminated after the enrolment of 41 of 1000 participants because clinicians had difficulties using cumulative fluid balance as the only estimate of fluid status (32% of participants had their initially registered cumulative fluid balance adjusted and 29% experienced one or more protocol violations). The baseline cumulative fluid balance was 6956 ml in the furosemide group and 6036 ml in the placebo group; on day three, the cumulative fluid balances were 1927 ml and 5139 ml. The median number of days alive and out of hospital at day 90 was 50 days in the furosemide group versus 45 days in the placebo group (mean difference 1 day, 95% CI -19 to 21, p-value .94).

Conclusions

The use of cumulative fluid balance as the only estimate of fluid status appeared too difficult to use in clinical practice. We were unable to provide precise estimates for any outcomes as only 4.1% of the planned sample size was randomised.     

Iron intake,oxidative stress-related genes and breast cancer risk

Iron has been suggested to contribute to breast cancer development through oxidative stress generation. Our study investigated associations between iron intake and breast cancer risk, overall and by menopausal and estrogen receptor/progesterone receptor (ER/PR) status, and modification by oxidative stress-related genetic polymorphisms (MnSOD, GSTM1 and GSTT1). A population-based case–control study (3,030 cases and 3,402 controls) was conducted in Ontario, Canada. Iron intake (total, dietary, supplemental, heme, nonheme) was assessed using a validated food frequency questionnaire. Odds ratios (OR) and 95% confidence intervals (CI) were estimated from multivariable logistic regression models. Interactions between iron intake and genotypes were assessed among 1,696 cases and 1,761 controls providing DNA. Overall, no associations were observed between iron intake and breast cancer risk. Among premenopausal women, total, dietary and dietary nonheme iron were positively associated with ER–/PR– breast cancer risk (all p_trend < 0.05). Among postmenopausal women, supplemental iron was associated with reduced breast cancer risk (OR_{>18 vs. 0 mg/day} = 0.68, 95% CI: 0.51–0.91), and dietary heme iron was associated with an increased risk, particularly the ER–/PR– subtype (OR_{highest vs. lowest quintile} = 1.69, 95% CI: 1.16–2.47; p_trend = 0.02). Furthermore, GSTT1 and combined GSTM1/GSTT1 polymorphisms modified some of the associations. For example, higher dietary iron was most strongly associated with increased breast cancer risk among women with GSTT1 deletion or GSTM1/GSTT1 double deletions (p_interaction < 0.05). Findings suggest that iron intake may have different effects on breast cancer risk according to menopausal and hormone receptor status, as well as genotypes affecting antioxidant capacity.     

Repeat capsule endoscopy in suspected gastrointestinal bleeding

Objectives: This study aims to review the utility of repeat capsule endoscopy (CE) with on-going concern of small bowel (SB) bleeding following initial SB investigation with CE.

Materials and methods: A specifically designed database of CE examinations performed over 13 years, with hospital records, was retrospectively interrogated for patients undergoing multiple CEs to investigate iron deficiency anaemia (IDA) or suspected SB bleeding.

Results: 1335/2276 (58.7%) of CEs were performed to investigate IDA or SB bleeding; 92 were repeat CEs carried out for ongoing clinical concern. The median time interval between initial and repeat CE procedures was 466.5 (range 1–3066) days. Twenty-four patients had initially normal CE; on repeat examination, abnormalities were detected in 11/24 (45.8%). 3/21 (14.2%) of patients with angioectasia on first CE had alternative causes for IDA or GI bleeding detected on repeat CE. Six patients with active bleeding, without an identifiable source on initial CE, undergoing repeat CE had a cause isolated in 5/6 (83.3%). Changing CE device did not affect diagnostic yield (DY) compared to repeat CE using the same device (27.5% to 26.8%).

Conclusions: It is known that CE can miss clinically relevant and serious lesions. Our results suggest that patients with an initially negative or inconclusive CE frequently have a cause of SB bleeding detected on repeat CE. The DY of repeat CE is highest in those with bleeding on their initial CE (83.3%) and lower in those with initially normal examinations (45.8%) or when an alternative cause, such as angioectasia is seen (14.2%).     

Iron overload in congenital haemolytic anaemias: role of hepcidin and cytokines and predictive value of ferritin and transferrin saturation

Iron overload (IO) is poorly investigated in the congenital haemolytic anaemias (CHAs), a heterogeneous group of rare inherited diseases encompassing abnormalities of the erythrocyte membrane and metabolism, and defects of the erythropoiesis. In this study we systematically evaluated routine iron parameters and cardiac and hepatic magnetic resonance imaging, together with erythropoietin, hepcidin, non-transferrin bound iron (NTBI), and cytokine serum levels in patients with different CHAs. We found that 40% of patients had a liver iron concentration (LIC) >4 mg Fe/g dry weight. Hepatic IO was associated with ferritin levels (P = 0·0025), transferrin saturation (TfSat, P = 0·002) and NTBI (P = 0·003). Moreover, ferritin >500 μg/l plus TfSat >60% was demonstrated as the best combination able to identify increased LIC, and TfSat alteration as more important in cases with discordant values. Possible confounding factors, such as transfusions, hepatic disease, metabolic syndrome and hereditary haemochromatosis-associated mutations, had negligible effects on IO. Erythropoietin and hepcidin levels were increased in CHAs compared with controls, correlating with LIC and ferritin, respectively. Regarding cytokines, γ-interferon (IFN-γ) was increased, and both interleukin 6 and IFN-γ levels positively correlated with ferritin and hepcidin levels. Overall, these findings suggest the existence of a vicious cycle between chronic haemolysis, inflammatory response and IO in CHAs.     

双氢青蒿素诱导肿瘤细胞铁死亡及其机制研究

目的阐明双氢青蒿素(DHA)诱导肿瘤细胞铁死亡的作用及其机制。方法利用3,3′,5,5′-四甲基联苯胺(TMB)检测DHA与FeSO_4体外芬顿样(Fenton)反应生成氧自由基(·OH)的能力;MTT法检测DHA对人肝癌HepG2细胞的毒性(包括FeSO_4与去铁胺预处理组)。MTT法考察谷胱甘肽(GSH)与铁死亡抑制剂(Fer-1)对DHA细胞毒性的影响;采用DCFH-DA染料考察DHA(包括FeSO_4预处理组)诱导的细胞内活性氧的生成能力;采用C11-BODIPY581/591与DiO分别考察DHA(包括FeSO_4预处理组)对细胞内脂质过氧化物生成能力以及细胞膜结构的影响;利用谷胱甘肽过氧化物酶4(GPX-4)试剂盒测定DHA(包括FeSO_4预处理组)对HepG2细胞内GPX-4活性的影响。结果 Fe~(2+)能够催化DHA发生芬顿样反应并生成·OH;DHA的半数抑制浓度(IC_(50))为(39.96±8.78)μmol/L,FeSO_4与去铁胺分别能够增加或者降低DHA的细胞毒性;DHA处理后细胞内活性氧含量与脂质过氧化物含量升高,细胞形态变大,细胞膜呈散点状分布并呈现解离状态。FeSO_4预处理组与DHA组相比较进一步增加细胞内活性氧含量与脂质过氧化物含量,并且细胞膜形态完全破坏。FeSO_4能够增强DHA对GPX-4活性的抑制作用。结论 DHA通过芬顿样反应升高细胞内活性氧而最终诱导肿瘤细胞铁死亡。另外,外源性铁可以加速DHA发生芬顿样反应进而加速肿瘤细胞铁死亡的发生与发展。     

Utilizing Edible Agar as a Carrier for Dual Functional Doxorubicin-Fe3O4 Nanotherapy Drugs

The purpose of this study was to use agar as a multifunctional encapsulating material to allow drug and ferromagnetism to be jointly delivered in one nanoparticle. We successfully encapsulated both Fe₃O₄ and doxorubicin (DOX) with agar as the drug carrier to obtain DOX-Fe₃O₄@agar. The iron oxide nanoparticles encapsulated in the carrier maintained good saturation of magnetization (41.9 emu/g) and had superparamagnetism. The heating capacity test showed that the specific absorption rate (SAR) value was 18.9 ± 0.5 W/g, indicating that the ferromagnetic nanoparticles encapsulated in the gel still maintained good heating capacity. Moreover, the magnetocaloric temperature could reach 43 °C in a short period of five minutes. In addition, DOX-Fe₃O₄@agar reached a maximum release rate of 85% ± 3% in 56 min under a neutral pH 7.0 to simulate the intestinal environment. We found using fluorescent microscopy that DOX entered HT-29 human colon cancer cells and reduced cell viability by 66%. When hyperthermia was induced with an auxiliary external magnetic field, cancer cells could be further killed, with a viability of only 15.4%. These results show that agar is an efficient multiple-drug carrier, and allows controlled drug release. Thus, this synergic treatment has potential application value for biopharmaceutical carrier materials.