Land suitability analysis for turmeric crop for humid tropical Kerala, India, under current and future climate scenarios using advanced geospatial techniques

BACKGROUND

Turmeric cultivation primarily thrives in India, followed by Bangladesh, Cambodia, Thailand, China, Malaysia, Indonesia and the Philippines. India leads globally in both area and production of turmeric. Despite this, there is a recognized gap in research regarding the impact of climate change on site suitability of turmeric. The primary objective of the present study was to evaluate both the present and future suitability of turmeric cultivation within the humid tropical region of Kerala, India, by employing advanced geospatial techniques. The research utilized meteorological data from the Indian Meteorological Department for the period of 1986-2020 as historical data and projected future data from the Coupled Model Intercomparison Project Phase 6 (CMIP6). Four climatic scenarios of shared socioeconomic pathway (SSP) from the Intergovernmental Panel on Climate Change AR6 model of MIROC6 for the year 2050 (SSP 1-2.6, SSP 2-4.5, SSP 3-7.0 and SSP 5-8.5) were used.

RESULTS

The results showed that suitable area for turmeric cultivation is declining in future scenario and this decline can be primarily attributed to fluctuations in temperature and an anticipated increase in rainfall in the year 2050. Notable changes in the spatial distribution of suitable areas over time were observed through the application of geographic information system (GIS) techniques. Importantly, as per the suitability criteria provided by ICAR-National Bureau of Soil Survey and Land Use Planning (ICAR-NBSS & LUP), all the districts in Kerala exhibited moderately suitable conditions for turmeric cultivation. With the GIS tools, the study identified highly suitable, moderately suitable, marginally suitable and not suitable areas of turmeric cultivation in Kerala. Presently 28% of area falls under highly suitable, 41% of area falls under moderately suitable and 11% falls under not suitable for turmeric cultivation. However, considering the projected scenarios for 2050 under the SSP framework, there will be a significant decrease in highly suitable area by 19% under SSP 5-8.5. This reduction in area will have an impact on the productivity of the crop as a result of changes in temperature and rainfall patterns.

CONCLUSION

The outcome of the present research suggests that the state of Kerala needs to implement suitable climate change adaptation and management strategies for sustaining the turmeric cultivation. Additionally, the present study includes a discussion on potential management strategies to address the challenges posed by changing climatic conditions for optimizing turmeric production in the region. © 2024 Society of Chemical Industry.

Inhibitory CARs fail to protect from immediate T cell cytotoxicity

Chimeric antigen receptors (CARs) equipped with an inhibitory signaling domain (iCARs) have been proposed as strategy to increase on-tumor specificity of CAR-T cell therapies. iCARs inhibit T cell activation upon antigen recognition and thereby program a Boolean NOT gate within the CAR-T cell. If cancer cells do not express the iCAR target antigen while it is highly expressed on healthy tissue, CAR/iCAR coexpressing T cells are supposed to kill cancer cells but not healthy cells expressing the CAR antigen. In this study, we employed a well-established reporter cell system to demonstrate high potency of iCAR constructs harboring BTLA-derived signaling domains. We then created CAR/iCAR combinations for the clinically relevant antigen pairs B7-H3/CD45 and CD123/CD19 and show potent reporter cell suppression by iCARs targeting CD45 or CD19. In primary human T cells αCD19-iCARs were capable of suppressing T cell proliferation and cytokine production. Surprisingly, the iCAR failed to veto immediate CAR-mediated cytotoxicity. Likewise, T cells overexpressing PD-1 or BTLA did not show impaired cytotoxicity toward ligand-expressing target cells, indicating that inhibitory signaling by these receptors does not mediate protection against cytotoxicity by CAR-T cells. Future approaches employing iCAR-equipped CAR-T cells for cancer therapy should therefore monitor off-tumor reactivity and potential CAR/iCAR-T cell dysfunction.

First record of Apanteles hemara (N.) on Leucinodes orbonalis Guenée and biodiversity of Hymenoptera parasitoids on Brinjal

The brinjal fruit and shoot borer (BFSB), Leucinodes orbonalis Guenée (Lepidoptera: Crambidae), is a very detrimental pest that causes significant economic losses to brinjal crop worldwide. Infested brinjal fruits were collected from vegetable fields located at the ICAR-Indian Agricultural Research Institute (ICAR-IARI), New Delhi, India, during two consecutive seasons (2021-2022). The larvae of the pest were brought to the laboratory and reared under controlled conditions of 25 ± 0.5 °C and 70 ± 5% relative humidity, for the emergence of parasitoids. In addition, the survey of Hymenoptera parasitoids in brinjal was conducted utilizing a sweep net and yellow pan trap over the course of two seasons. The results reveal that five parasitoid species were emerged from L. orbonalis viz., Apanteles hemara Nixon, 1965, Bracon greeni Ashmead 1896 (Hymenoptera: Braconidae), Goryphus nursei (Cameron, 1907), Trathala flavoorbitalis (Cameron, 1907) (Hymenoptera: Ichneumonidae) and Spalangia gemina Boucek 1963 (Hymenoptera: Spalangiidae). Out of these, A. hemara and S. gemina were documented as new occurrences in Delhi. Additionally, A. hemara was recorded for the first time as a parasite on L. orbonalis. Trathala flavoorbitalis was observed during both seasons and exhibited higher parasitism reaching 15.55% and 18.46% in July and August 2022, respectively. However, the average parasitism (%) recorded by A. hemara, B. greeni, G. nursei, T. flavoorbitalis and S. gemina was 3.10%, 1.76%, 1.10%, 9.28% and 1.20% respectively. Furthermore, the findings showed a significant (p ≤ 0.01) strongly positive correlation between fruit infestation (%) by L. orbonalis and parasitism (%). The survey indicates the presence of a broad group (19 families and 60 species) of Hymenoptera parasitoids in the brinjal crop ecosystem in Delhi which could be valuable in biological control. In light of these results, this study revealed that A. hemara and other parasitoids identified in this study alongside T. flavoorbitalis would be ideal biocontrol agents within the integrated pest management (IPM) program of BFSB in Delhi.

One-carbon metabolite supplementation to nutrient-restricted beef heifers affects placental vascularity during early pregnancy

We hypothesized that restricted maternal nutrition and supplementation of one-carbon metabolites (OCM; methionine, folate, choline, and vitamin B12) would affect placental vascular development during early pregnancy. A total of 43 cows were bred, and 32 heifers successfully became pregnant with female calves, leading to the formation of four treatment groups: CON - OCM (n = 8), CON + OCM (n = 7), RES - OCM (n = 9), and RES + OCM (n = 8). The experimental design was a 2 × 2 factorial, with main factors of dietary intake affecting average daily gain: control (CON; 0.6 kg/d ADG) and restricted (RES; -0.23 kg/d ADG); and OCM supplementation (+OCM) in which the heifers were supplemented with rumen-protected methionine (7.4 g/d) and choline (44.4 g/d) and received weekly injections of 320 mg of folate and 20 mg of vitamin B12, or received no supplementation (-OCM; corn carrier and saline injections). Heifers were individually fed and randomly assigned to treatment at breeding (day 0). Placentomes were collected on day 63 of gestation (0.225 of gestation). Fluorescent staining with CD31 and CD34 combined with image analysis was used to determine the vascularity of the placenta. Images were analyzed for capillary area density (CAD) and capillary number density (CND). Areas evaluated included fetal placental cotyledon (COT), maternal placental caruncle (CAR), whole placentome (CAR + COT), intercotyledonary fetal membranes (ICOT, or chorioallantois), intercaruncular endometrium (ICAR), and endometrial glands (EG). Data were analyzed with the GLM procedure of SAS, with heifer as the experimental unit and significance at P ≤ 0.05 and a tendency at P > 0.05 and P < 0.10. Though no gain × OCM interactions existed (P ≥ 0.10), OCM supplementation increased (P = 0.01) CAD of EG, whereas nutrient restriction tended (P < 0.10) to increase CAD of ICOT and CND of COT. Additionally, there was a gain × OCM interaction (P < 0.05) for CAD within the placentome and ICAR, such that RES reduced and supplementation of RES with OCM restored CAD. These results indicate that maternal rate of gain and OCM supplementation affected placental vascularization (capillary area and number density), which could affect placental function and thus the efficiency of nutrient transfer to the fetus during early gestation.

Effects of a second iron-dextran injection administered to piglets during lactation on differential gene expression in liver and duodenum at weaning

Six female littermate piglets were used in an experiment to evaluate the mRNA expression in tissues from piglets given one or two 1 mL injections of iron dextran (200 mg Fe/mL). All piglets in the litter were administered the first 1 mL injection < 24 h after birth. On day 7, piglets were paired by weight (mean body weight = 1.72 ± 0.13 kg) and one piglet from each pair was randomly selected as control (CON) and the other received a second injection (+Fe). At weaning on day 22, each piglet was anesthetized, and samples of liver and duodenum were taken from the anesthetized piglets and preserved until mRNA extraction. differential gene expression data were analyzed with a fold change cutoff (FC) of |1.2| P < 0.05. Pathway analysis was conducted with Z-score cutoff of P < 0.05. In the duodenum 435 genes were significantly changed with a FC ≥ |1.2| P < 0.05. In the duodenum, Claudin 1 and Claudin 2 were inversely affected by + Fe. Claudin 1 (CLDN1) plays a key role in cell-to-cell adhesion in the epithelial cell sheets and was upregulated (FC = 4.48, P = 0.0423). Claudin 2 (CLDN2) is expressed in cation leaky epithelia, especially during disease or inflammation and was downregulated (FC = -1.41, P = 0.0097). In the liver, 362 genes were expressed with a FC ≥ |1.2| P < 0.05. The gene most affected by a second dose of 200 mg Fe was hepcidin antimicrobial peptide (HAMP) with a FC of 40.8. HAMP is a liver-produced hormone that is the main circulating regulator of Fe absorption and distribution across tissues. It also controls the major flows of Fe into plasma by promoting endocytosis and degradation of ferroportin (SLC4A1). This leads to the retention of Fe in Fe-exporting cells and decreased flow of Fe into plasma. Gene expression related to metabolic pathway changes in the duodenum and liver provides evidence for the improved feed conversion and growth rates in piglets given two iron injections preweaning with contemporary pigs in a companion study. In the duodenum, there is a downregulation of gene clusters associated with gluconeogenesis (P < 0.05). Concurrently, there was a decrease in the mRNA expression of genes for enzymes required for urea production in the liver (P < 0.05). These observations suggest that there may be less need for gluconeogenesis, and possibly less urea production from deaminated amino acids. The genomic and pathway analyses provided empirical evidence linking gene expression with phenotypic observations of piglet health and growth improvements.

Suspension syndrome: a scoping review and recommendations from the International Commission for Mountain Emergency Medicine (ICAR MEDCOM)

BACKGROUND

Suspension syndrome describes a multifactorial cardio-circulatory collapse during passive hanging on a rope or in a harness system in a vertical or near-vertical position. The pathophysiology is still debated controversially.

AIMS

The International Commission for Mountain Emergency Medicine (ICAR MedCom) performed a scoping review to identify all articles with original epidemiological and medical data to understand the pathophysiology of suspension syndrome and develop updated recommendations for the definition, prevention, and management of suspension syndrome.

METHODS

A literature search was performed in PubMed, Embase, Web of Science and the Cochrane library. The bibliographies of the eligible articles for this review were additionally screened.

RESULTS

The online literature search yielded 210 articles, scanning of the references yielded another 30 articles. Finally, 23 articles were included into this work.

CONCLUSIONS

Suspension Syndrome is a rare entity. A neurocardiogenic reflex may lead to bradycardia, arterial hypotension, loss of consciousness and cardiac arrest. Concomitant causes, such as pain from being suspended, traumatic injuries and accidental hypothermia may contribute to the development of the Suspension Syndrome. Preventive factors include using a well-fitting sit harness, which does not cause discomfort while being suspended, and activating the muscle pump of the legs. Expediting help to extricate the suspended person is key. In a peri-arrest situation, the person should be positioned supine and standard advanced life support should be initiated immediately. Reversible causes of cardiac arrest caused or aggravated by suspension syndrome, e.g., hyperkalaemia, pulmonary embolism, hypoxia, and hypothermia, should be considered. In the hospital, blood and further exams should assess organ injuries caused by suspension syndrome.

Termination of Cardiopulmonary Resuscitation in Mountain Rescue: A Scoping Review and ICAR MedCom 2023 Recommendations

Lugnet, Viktor, Miles McDonough, Les Gordon, Mercedes Galindez, Nicolas Mena Reyes, Alison Sheets, Ken Zafren, and Peter Paal. Termination of cardiopulmonary resuscitation in mountain rescue: a scoping review and ICAR MedCom 2023 recommendations. High Alt Med Biol. 24:274-286, 2023. Background: In 2012, the International Commission for Mountain Emergency Medicine (ICAR MedCom) published recommendations for termination of cardiopulmonary resuscitation (CPR) in mountain rescue. New developments have necessitated an update. This is the 2023 update for termination of CPR in mountain rescue. Methods: For this scoping review, we searched the PubMed and Cochrane libraries, updated the recommendations, and obtained consensus approval within the writing group and the ICAR MedCom. Results: We screened a total of 9,102 articles, of which 120 articles met the inclusion criteria. We developed 17 recommendations graded according to the strength of recommendation and level of evidence. Conclusions: Most of the recommendations from 2012 are still valid. We made minor changes regarding the safety of rescuers and responses to primary or traumatic cardiac arrest. The criteria for termination of CPR remain unchanged. The principal changes include updated recommendations for mechanical chest compression, point of care ultrasound (POCUS), extracorporeal life support (ECLS) for hypothermia, the effects of water temperature in drowning, and the use of burial times in avalanche rescue.

Dual-inhibitory domain iCARs improve the efficiency of the AND-NOT gate CAR T strategy

CAR (chimeric antigen receptor) T cell therapy has shown clinical success in treating hematological malignancies, but its treatment of solid tumors has been limited. One major challenge is on-target, off-tumor toxicity, where CAR T cells also damage normal tissues that express the targeted antigen. To reduce this detrimental side-effect, Boolean-logic gates like AND-NOT gates have utilized an inhibitory CAR (iCAR) to specifically curb CAR T cell activity at selected nonmalignant tissue sites. However, the strategy seems inefficient, requiring high levels of iCAR and its target antigen for inhibition. Using a TROP2-targeting iCAR with a single PD1 inhibitory domain to inhibit a CEACAM5-targeting CAR (CEACAR), we observed that the inefficiency was due to a kinetic delay in iCAR inhibition of cytotoxicity. To improve iCAR efficiency, we modified three features of the iCAR-the avidity, the affinity, and the intracellular signaling domains. Increasing the avidity but not the affinity of the iCAR led to significant reductions in the delay. iCARs containing twelve different inhibitory signaling domains were screened for improved inhibition, and three domains (BTLA, LAIR-1, and SIGLEC-9) each suppressed CAR T function but did not enhance inhibitory kinetics. When inhibitory domains of LAIR-1 or SIGLEC-9 were combined with PD-1 into a single dual-inhibitory domain iCAR (DiCARs) and tested with the CEACAR, inhibition efficiency improved as evidenced by a significant reduction in the inhibitory delay. These data indicate that a delicate balance between CAR and iCAR signaling strength and kinetics must be achieved to regulate AND-NOT gate CAR T cell selectivity.

Assessment of expected breeding value for milk production traits of Murrah buffaloes under different heat stress zones in Indian sub-tropical climatic conditions

Present study was conducted to investigate the impact of temperature humidity index (THI) on expected breeding value (EBV) for daily milk yield (DMY) and monthly test day fat% (MTDF%) and monthly test day SNF% (MTDSNF%) of Murrah buffaloes at ICAR-National Dairy Research Institute, Karnal. 302,101 records of DMY and 9864 records each on MTDF% and MTDSNF% buffaloes spanned over 20 years (1994 to 2013) from NDRI, Karnal, and meteorological were collected from ICAR-CSSRI, Karnal. The year was classified into three zones: non-heat stress (NHSZ), heat stress (HSZ), and critical heat stress zone (CHSZ) based on THI. The heritability (h2) estimates for DMY, MTDF%, and MTDSNF% in NHSZ were 0.432 ± 0.054, 0.090 ± 0.004, and 0.070 ± 0.002; in HSZ 0.491 ± 0.073, 0.112 ± 0.003, and 0.052 ± 0.001; and in CHSZ 0.524 ± 0.077, 0.116 ± 0.004, and 0.092 ± 0.003, respectively. The repeatability (r) for DMY, MTDF%, and MTDSNF% in NHSZ were 0.528 ± 0.006, 0.166 ± 0.007, and 0.135 ± 0.007; in HSZ 0.572 ± 0.007, 0.198 ± 0.006, and 0.077 ± 0.006; and in CHSZ 0.599 ± 0.008, 0.217 ± 0.004, and 0.156 ± 0.009, respectively. EBV for DMY and MTDF% was maximum in NHSZ (8.85 kg and 7.85%) and in HSZ (7.27 kg and7.78%) and lowest (6.90 kg and 7.77%) at CHSZ. For MTDSNF%, EBV was highest during NHSZ (9.6403), declined to 9.6265 at HSZ, and marginally elevated to 9.6271 at CHSZ. Impact of climatic factors on milk production and constituent traits is vital, and proper management should be followed during the heat stress and critical heat stress periods to improve the production performance of Murrah buffaloes.

Reducing unnecessary premedication prior to parenteral iron therapy: A quality improvement project

BACKGROUND

Intravenous (IV) iron carries risks of mild, self-limiting, tryptase-negative Fishbane and complement activation-related pseudo-allergy reactions, with rare reports of anaphylaxis. Historically, high-molecular-weight iron dextran (HMWID) was associated with a higher incidence of anaphylaxis and empiric premedication with antihistamines/corticosteroids have been used to mitigate this risk. HMWID is no longer available and the risk of hypersensitivity reactions with newer IV iron formulations is low. Therefore, the use of routine prophylactic premedication in all patients is not justified but should be considered in high-risk patients.

STUDY DESIGN AND METHODS

Our primary aim was to reduce inappropriate premedication before IV iron administration by 50% so that our institution's hematology providers only prescribe premedications to patients at high risk of having a severe reaction. Interventions included a multidisciplinary education initiative to highlight current evidence against universal administration of premedications and revision of the IV iron informed consent form and electronic order set.

RESULTS

We measured the success of our intervention by comparing data collected during a 6-month pre-intervention period (837 infusions) to a 6-month post-intervention period (947 infusions). Inappropriate administration of premedications decreased from 79% in the pre-intervention period compared to 65% in the post-intervention period. We found no significant difference in the number of Fishbane reactions, severe reactions, and emergency room admissions, despite this reduction in premedication use.

DISCUSSION

Although we did not reach our goal of a 50% reduction in inappropriate premedication use, opportunities for process improvements were uncovered and are being explored in the next cycle of this quality improvement project.

Meeting report: 36th International Conference on Antiviral Research in Lyon, France - March 13-17, 2023

The 36th International Conference on Antiviral Research (ICAR), sponsored by the International Society for Antiviral Research (ISAR), was held March 13-17, 2023, in Lyon, France, and concurrently through an interactive remote meeting platform. Here we provide a report summarizing the presentations at the 36th ICAR, including the ISAR speaker awards. We also detail special events, sessions, and additional awards conferred at the meeting. ICAR returned to in-person meetings in 2022, convening in Seattle, WA, USA. The 36th ICAR is the first in-person meeting of the society in Europe since the beginning of the COVID-19 pandemic, which restricted most events to virtual attendance to help mitigate the spread and subsequent public health impact of SARS-CoV-2. An exceptionally high number of registrants and record attendance at this year's ICAR, along with a vast array of demonstrable expertise in a variety of antiviral research-related fields, reflected a strong and growing antiviral research community committed to improving health outcomes from viral diseases, including SARS-CoV-2, and to future pandemic preparedness. This report highlights the breadth of expertise, quality of research, and notable advancements that were contributed by members of ISAR and other participants at the meeting. ICAR aims to continue to provide a platform for sharing information, fostering collaborations, and supporting trainees in the field of antiviral research. The 37th ICAR will be held in Gold Coast, Australia, May 20-24, 2024.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Meeting report: 35th International Conference on Antiviral Research in Seattle, Washington, USA - March 21-25, 2022

The 35th International Conference on Antiviral Research (ICAR), sponsored by the International Society for Antiviral Research (ISAR), was held in Seattle, Washington, USA, on March 21-25, 2022 and concurrently through an interactive remote meeting platform. This report gives an overview of the conference on behalf of the society. It provides a general review of the meeting and awardees, summarizing the presentations and their main conclusions from the perspective of researchers active in many different areas of antiviral research and development. Through ICAR, leaders in the field of antiviral research were able to showcase their efforts, as participants learned about key advances in the field. The impact of these efforts was exemplified by many presentations on SARS-CoV-2 demonstrating the remarkable response to the ongoing pandemic, as well as future pandemic preparedness, by members of the antiviral research community. As we address ongoing outbreaks and seek to mitigate those in the future, this meeting continues to support outstanding opportunities for the exchange of knowledge and expertise while fostering cross-disciplinary collaborations in therapeutic and vaccine development. The 36th ICAR will be held in Lyon, France, March 13-17, 2023.

Estimation of genetic parameters of growth traits for direct and maternal effects in Murrah buffalo

An understanding of genetic principles and environmental factors affecting the growth traits is essential to implement optimal breeding and selection programs. Early growth is an indicator of future success in production and reproduction status of dairy animals. In this study, a total of 18,989 records of body weight were used to estimate genetic parameters of body weight at birth (BW), 3 months (3BW), 6 months (6BW), 9 months (9BW),12 months (12BW), 18 months (18BW), 24 months (24 BW), 30 months (3BW), and 36 months (36BW) in Murrah buffalo at ICAR-NDRI Karnal, Haryana, for the period 1974-2019. The genetic parameters were estimated using the average information restricted maximum likelihood (AIREML) procedure by excluding or including maternal effects. Six analytical models were fitted in order to optimize the model for each trait. The most appropriate univariate model was selected based on the log likelihood ratio test (LRT). Influencing factors like calf sex, period of birth, season of birth, and dam's parity were investigated. The results showed that the maternal genetic effects, in addition to direct additive effects, were important for unbiased and accurate genetic parameter estimates of growth traits in Murrah buffaloes. Total heritability estimates h²_T1 for BW, 3BW, 6BW, 9BW, 12BW, 18BW, 24BW, 30BW, and 36BW were 0.25, 0.04, 0.14, 0.16, 0.10, 0.15, 0.21, 0.24, and 0.23, respectively. Maternal effect was significant for birth weight and accounted for 13% variation through maternal genetic and 5% variability through maternal permanent environmental effect. Maternal genetic effect was also important for other traits. However, it interfered with the estimates of variance ratios in live weight traits owing to large and negative covariance between direct and maternal genetic effects. Direct genetic correlations between body weight traits were positive and high ranging from 0.10 to 0.94. Results revealed that the Murrah herd has a sizable genetic variability for growth traits and hence, there is sufficient scope for selection for achieving better growth rate if selection in this direction is applied. Owing to higher positive genetic correlation of 6BW with later ages, the scope of indirect selection for optimum growth in later ages can be aimed at by selecting animals for their higher 6-month live weight.

Molecular modeling and in vitro studies of gedunin a potent alpha-amylase inhibitor and alpha-glucosidase inhibitor

The present study explores the potential of the Azadirachta indica (Neem) plant parts (stem and bark) component gedunin for inhibition of alpha-amylase and alpha glucosidase. In contrast, Methanol at 50 mg/ml and 65 mg/ml had the lowest IC50 in alpha glucosidase and alpha amylase with noncompetitive and mixed inhibition, respectively. Azadirachta indica seeds collected from ICAR showed anti-diabetes activity in vitro and in vivo seeds collected were subjected to soxhlet and nonsoxhlet techniques followed by chromatography. HR-LCMS, HPLC, and FTIR to comprehend phytoconstituents present in the extract were used to comprehend phytoconstituents present in the extract and showed the presence gedunin. Among many hits observed, gedunin was used for docking studies using ICM software and for molecular dynamic simulation using gromacs. The results show significant alpha-amylase inhibitory activity and alpha glucosidase inhibitory activity and interaction of ligand targeting these enzymes, which can be used for cross-validation, in vitro using ligplot maps and visualization.

Bayesian spatial correlation, heterogeneity and spillover effect modeling for speed mean and variance on urban road networks

Analyzing speed mean and variance is vital to safety management in urban roadway networks. However, modeling speed mean and variance on structured roads could be influenced by the spatial effects, which are rarely addressed in the existing studies. The inadequacy may lead to biased conclusions when considering vehicle speed as a surrogate safety measure. The current study focuses on developing a Bayesian modeling approach with three types of spatial effects, i.e., spatial correlation, spatial heterogeneity, and spillover effect. To capture the spatial correlation, the study employs the intrinsic conditional autoregressive (ICAR) models, spatial lag models (SLM), and spatial error models (SEM). Spatial heterogeneity and spillover effect are considered by the random parameters approach and spatially lagged covariates (SLCs). Speed data are collected from the float cars running on 134 urban arterials in Chengdu, China. The results indicate that the random parameters ICAR model with SLCs (RPICAR-SLC) outperforms others in terms of goodness-of-fit, accuracy, and efficiency for modeling speed mean, while the random parameters ICAR model (RPICAR) is the best for modeling speed variance. Moreover, RPICAR-SLC and RPICAR models are beneficial to address spatial correlation of residuals, explaining the unobserved influence among the observations, and are less likely to cause biased or overestimated parameters. The study also discusses how traffic conditions, road characteristics, traffic management strategies, and facilities on roadway networks influence speed mean and variance. The findings highlight the importance of multi-type spatial effects on modeling speed mean and variance along the structured roadways.

Form of dietary selenium affects mRNA encoding interferon-stimulated and progesterone-induced genes in the bovine endometrium and conceptus length at maternal recognition of pregnancy

Widespread regions of the southeast United States have soils, and hence forages, deficient in selenium (Se), necessitating Se supplementation to grazing cattle for optimal immune function, growth, and fertility. We have reported that supplementation with an isomolar 1:1 mix (MIX) of inorganic (ISe) and organic (OSe) forms of Se increases early luteal phase (LP) concentrations of progesterone (P4) above that in cows on ISe or OSe alone. Increased early LP P4 advances embryonic development. Our objective was to determine the effects of the form of Se on the development of the bovine conceptus and the endometrium using targeted real-time PCR (qPCR) on day 17 of gestation, the time of maternal recognition of pregnancy (MRP). Angus-cross yearling heifers underwent 45-d Se-depletion then repletion periods, then at least 90 d of supplementation (TRT) with 35 ppm Se per day as either ISe (n = 10) or MIX (n = 10). Heifers were inseminated to a single sire after detected estrus (day 0). On day 17 of gestation, caruncular (CAR) and intercaruncular (ICAR) endometrial samples and the developing conceptus were recovered from pregnant heifers (ISe, n = 6 and MIX, n = 6). qPCR was performed to determine the relative abundance of targeted transcripts in CAR and ICAR samples, with the expression data subjected to one-way ANOVA to determine TRT effects. The effect of TRT on conceptus development was analyzed using a one-tailed Student's t-test. When compared with ISe-treated heifers, MIX heifers had decreased (P < 0.05) abundance of several P4-induced and interferon-stimulated mRNA transcripts, including IFIT3, ISG15, MX1, OAS2, RSAD2, DGAT2, FGF2 in CAR and DKK1 in ICAR samples and tended (P ≤ 0.10) to have decreased mRNA abundance of IRF1, IRF2, FOXL2, and PGR in CAR samples, and HOXA10 and PAQR7 in ICAR samples. In contrast, MIX-supplemented heifers had increased (P < 0.05) mRNA abundance of MSTN in ICAR samples and an increase in conceptus length (ISe: 17.45 ± 3.08 cm vs. MIX: 25.96 ± 3.95 cm; P = 0.05). Notably, myostatin increases glucose secretion into histotroph and contributes to advanced conceptus development. This advancement in conceptus development occurred in the presence of similar concentrations of serum P4 (P = 0.88) and whole blood Se (P = 0.07) at MRP.

A Comparison of International Guidelines for Rhinosinusitis

The European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS), latest version EPOS2020, and the International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS), latest version ICAR-RS-2021, assimilate thousands of articles on the topic of rhinosinusitis. Encompassing scores of subtopics and relying on the perspectives of many international experts, EPOS2020 and ICAR-RS-2021 reduce the existing data into consumable formats and create evidence-based recommendations. The approaches and findings are similar in many respects but have significant differences. This clinical commentary, authored by some of the principal authors of these documents, compares and contrasts EPOS2020 and ICAR-RS-2021, examining methodology, diagnostic and treatment recommendations, and each document's emphases. This commentary demonstrates that, through somewhat differing methodologies, the 2 documents arrive at largely similar conclusions. Those who care for patients suffering from rhinosinusitis will find the documents complementary and valuable in their differences as much as in their similarities.

Diagnosis of Systemic Diseases Using Infrared Spectroscopy: Detection of Iron Overload in Plasma-Preliminary Study

Despite the important role of iron in cellular homeostasis, iron overload (IO) is associated with systemic and tissue deposits which damage several organs. In order to reduce the impact caused by IO, invasive diagnosis exams (e.g., biopsies) and minimally invasive methods were developed including computed tomography and magnetic resonance imaging. However, current diagnostic methods are still time-consuming and expensive. A cost-effective solution is using Fourier-transform infrared spectroscopy (FTIR) for real-time and molecular-sensitive biofluid analysis during conventional laboratory exams. In this study, we performed the first evaluation of the accuracy of FTIR for IO diagnosis. The study was performed by collecting FTIR spectra of plasma samples of five rats intravenously injected with iron-dextran and five control rats. We developed a classification model based on principal component analysis and supervised methods including J48, random forest, multilayer perceptron, and radial basis function network. We achieved 100% accuracy for the classification of the IO status and provided a list of possible biomolecules related to the vibrational modes detected. In this preliminary study, we give a first step towards real-time diagnosis for acute IO or intoxication. Furthermore, we have expanded the literature knowledge regarding the pathophysiological changes induced by iron overload.

PPAR agonist fenofibrate attenuates iron-induced liver injury in mice by modulating the Sirt3 and -catenin signaling

Iron accumulation is frequently associated with chronic liver diseases. However, our knowledge on how iron contributes to the liver injury is limited. Aberrant Wnt/β-catenin signaling is a hallmark of several hepatic pathologies. We recently reported that peroxisome proliferator-activated receptor α (PPARα) agonist, fenofibrate, prevents iron-induced oxidative stress and β-catenin signaling by chelating the iron. Sirtuin3 (Sirt3), a type of NAD+-dependent deacetylase, that plays a critical role in metabolic regulation was found to prevent ischemia reperfusion injury (IRI) by normalizing the Wnt/β-catenin pathway. In the present study, we explored if fenofibrate prevents iron-induced liver injury by regulating the Sirt3 and β-catenin signaling. In vitro and in vivo iron treatment resulted in the downregulation of PPARα, Sirt3, active β-catenin, and its downstream target gene c-Myc in the mouse liver. Pharmacological activation of Sirt3, both in vitro and in vivo, by Honokiol (HK), a known activator of Sirt3, abrogated the inhibitory effect of iron overload on active β-catenin expression and prevented the iron-induced upregulation of α smooth muscle actin (αSMA) and TGFβ expression. Intrinsically, PPARα knockout mice showed significant downregulation of hepatic Sirt3 levels. In addition, treatment of iron overload mice with PPARα agonist fenofibrate reduced hepatic iron accumulation and prevented iron-induced downregulation of liver Sirt3 and active β-catenin, mitigating the progression of fibrosis. Thus, our results establish a novel link between hepatic iron and PPARα, Sirt3, and β-catenin signaling. Further exploration on the mechanisms by which fenofibrate ameliorates iron-induced liver injury likely has significant therapeutic impact on iron-associated chronic liver diseases.NEW & NOTEWORTHY Hepatic intracellular iron accumulation has been implicated in the pathophysiology of chronic liver diseases. In this study, we identified a novel mechanism involved in the progression of fibrosis. Excess iron accumulation in liver caused downregulation of PPARα-Sirt3-Wnt signaling leading to fibrosis. This work has significant translational potential as PPARα agonist fenofibrate could be an attractive therapeutic drug for the treatment of liver disorders associated with iron overload.

Chronic Iron Overload Restrains the Benefits of Aerobic Exercise to the Vasculature

Physical exercise is a well-recognized effective non-pharmacological therapy for cardiovascular diseases. However, because iron is essential element in many physiological processes including hemoglobin and myoglobin synthesis, thereby playing a role on oxygen transport, many athletes use iron supplement to improve physical performance. Regarding this, iron overload is associated with oxidative stress and damage to various systems, including cardiovascular. Thus, we aimed to identify the vascular effects of aerobic exercise in a rat model of iron overload. Male Wistar rats were treated with 100 mg/kg/day iron-dextran, i.p., 5 days a week for 4 weeks, and then underwent aerobic exercise protocol on a treadmill at moderate intensity, 60 min/day, 5 days a week for 8 weeks. Exercise reduced vasoconstrictor response of isolated aortic rings by increasing participation of nitric oxide (NO) and reducing oxidative stress, but these benefits to the vasculature were not observed in rats previously subjected to iron overload. The reduced vasoconstriction in the exercised group was reversed by incubation with superoxide dismutase (SOD) inhibitor, suggesting that increased SOD activity by exercise was lost in iron overload rats. Iron overload groups increased serum levels of iron, transferrin saturation, and iron deposition in the liver, gastrocnemius muscle, and aorta, and the catalase was overexpressed in the aorta probably as a compensatory mechanism to the increased oxidative stress. In conclusion, despite the known beneficial effects of aerobic exercise on vasculature, our results indicate that previous iron overload impeded the anticontractile effect mediated by increased NO bioavailability and endogenous antioxidant response due to exercise protocol.

Orchestrated regulation of iron trafficking proteins in the kidney during iron overload facilitates systemic iron retention

The exact route of iron through the kidney and its regulation during iron overload are not completely elucidated. Under physiologic conditions, non-transferrin and transferrin bound iron passes the glomerular filter and is reabsorbed through kidney epithelial cells, so that hardly any iron is found in the urine. To study the route of iron reabsorption through the kidney, we analyzed the location and regulation of iron metabolism related proteins in kidneys of mice with iron overload, elicited by iron dextran injections. Transferrin Receptor 1 was decreased as expected, following iron overload. In contrast, the multi-ligand hetero-dimeric receptor-complex megalin/cubilin, which also mediates the internalization of transferrin, was highly up-regulated. Moreover, with increasing iron, intracellular ferritin distribution shifted in renal epithelium from an apical location to a punctate distribution throughout the epithelial cells. In addition, in contrast to many other tissues, the iron exporter ferroportin was not reduced by iron overload in the kidney. Iron accumulated mainly in interstitial macrophages, and more prominently in the medulla than in the cortex. This suggests that despite the reduction of Transferrin Receptor 1, alternative pathways may effectively mediate re-absorption of iron that cycles through the kidney during parenterally induced iron-overload. The most iron consuming process of the body, erythropoiesis, is regulated by the renal erythropoietin producing cells in kidney interstitium. We propose, that the efficient re-absorption of iron by the kidney, also during iron overload enables these cells to sense systemic iron and regulate its usage based on the systemic iron state.

Melatonin protects bone marrow mesenchymal stem cells against iron overload-induced aberrant differentiation and senescence

Bone marrow mesenchymal stem cells (BMSCs) are an expandable population of stem cells which can differentiate into osteoblasts, chondrocytes and adipocytes. Dysfunction of BMSCs in response to pathological stimuli contributes to bone diseases. Melatonin, a hormone secreted from pineal gland, has been proved to be an important mediator in bone formation and mineralization. The aim of this study was to investigate whether melatonin protected against iron overload-induced dysfunction of BMSCs and its underlying mechanisms. Here, we found that iron overload induced by ferric ammonium citrate (FAC) caused irregularly morphological changes and markedly reduced the viability in BMSCs. Consistently, osteogenic differentiation of BMSCs was significantly inhibited by iron overload, but melatonin treatment rescued osteogenic differentiation of BMSCs. Furthermore, exposure to FAC led to the senescence in BMSCs, which was attenuated by melatonin as well. Meanwhile, melatonin was able to counter the reduction in cell proliferation by iron overload in BMSCs. In addition, protective effects of melatonin on iron overload-induced dysfunction of BMSCs were abolished by its inhibitor luzindole. Also, melatonin protected BMSCs against iron overload-induced ROS accumulation and membrane potential depolarization. Further study uncovered that melatonin inhibited the upregulation of p53, ERK and p38 protein expressions in BMSCs with iron overload. Collectively, melatonin plays a protective role in iron overload-induced osteogenic differentiation dysfunction and senescence through blocking ROS accumulation and p53/ERK/p38 activation.

Mechanism of protective effects of Danshen against iron overload-induced injury in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Danshen (Salvia miltiorrhiza) has been widely prescribed in traditional folk medicine for treatment of hepatic and cardiovascular diseases in China and other Asian countries for several hundred years.

MATERIALS AND METHODS

Sixty male mice were randomly divided into five groups: control, iron overload, low-dose Danshen (L-Danshen, 3g/kg/day), high-dose Danshen (H-Danshen, 6g/kg/day) and deferoxamine (DFO) groups (n=12 per group). Iron dextran was injected intraperitoneally (i.p.) at 50mg/kg body weight/day to establish the iron overload model. While control mice received saline, mice of the treated groups simultaneously received (i.p.) injections of L-Danshen, H-Danshen or DFO daily for 2 weeks. At the end of the experiment, changes in alanine aminotransferase (ALT) and aspartate aminotransferase (AST), glutathione peroxidase (GSH-Px), superoxide desmutase (SOD) and malondialdehyde (MDA) were measured, and histological changes were observed by Prussian blue or hematoxylin and eosin staining of the liver. Apoptosis was detected by terminal-deoxynucleotidyl transferase mediated nick end labeling.

RESULTS

Treatment of iron overloaded mice with either low or high doses of Danshen not only significantly attenuated the hepatic dysfunction (ALT/AST levels), decreased the content of MDA and increased the activities of GSH-Px and SOD, it also suppressed apoptosis in hepatocytes. Histopathological examination showed that treatment with Danshen reduced iron deposition and ameliorated pathological changes in the liver of iron overloaded mice.

CONCLUSIONS

Danshen demonstrated significant protective effects in the liver of iron overloaded mice, which were at least partly due to the decrease of iron deposition and inhibition of lipid peroxidation and hepatocyte apoptosis.

Dynamic contrast-enhanced ultrasound (DCE-US) for easy and rapid evaluation of hepatocellular carcinoma compared to dynamic contrast-enhanced computed tomography (DCE-CT)--a pilot study

PURPOSE

To check the feasibility of the easy quantification of tumor vascularization derived from dynamic contrast-enhanced ultrasound (DCE-US) in comparison to dynamic contrast-enhanced computed tomography (DCE-CT) in patients with hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

19 patients with cirrhosis and histologically proven HCC prospectively underwent CEUS (SonoVue) and CT (Imeron400). Following CEUS, the software ImageJ was used for the easy quantification of the echogenicity in HCC lesions and tumor-free liver parenchyma. For DCE-CT we used the software Hepacare and created arterial enhancement fraction color maps of the whole liver and HCC lesions.

RESULTS

Unifocal/multifocal HCCs were detected in 12/7 (US) and 10/9 patients (CT) and biopsied nodules were defined as a reference lesion with a median of 40 mm (US) and 42 mm (CT). CEUS showed HCC-typical hyper-/hypoenhancement in the arterial/late phase in 16/19 reference lesions, while all reference lesions showed an HCC-typical vascular pattern in CT. With DCE-US, quantitative assessment could not be performed in 3/19 patients due to respiratory motion or insufficient image quality. 13/16 reference lesions showed an HCC-typical vascular pattern. Quantitative assessment was possible with DCE-CT in all patients and all reference nodules showed HCC-typical values of the arterial enhancement fraction. There was no statistical difference between CEUS, DCE-US and DCE-CT in the quantitative assessment of contrast enhancement.

CONCLUSION

The quantitative evaluation of DCE-US was feasible in HCC without a statistical difference with respect to DCE-CT. Further studies with a larger study population including small nodules ≤ 2 cm are needed to assess whether this technique is helpful in routine ultrasound.

Clinically applicable 7-Tesla magnetic resonance visualization of transplanted human adult stem cells labeled with CliniMACS nanoparticles

BACKGROUND

Intra-myocardial transplantation of bone marrow derived cells is currently under clinical evaluation as a therapy for heart failure. A major limitation of all clinical studies for myocardial restoration through cell transfer is the inability to track the fate of the transplanted cells. We present a clinically applicable technique using advanced ultra high-field 7-Tesla (7T) magnetic resonance imaging (MRI) of nanoparticle-labeled transplanted human EPCs in porcine ischemic hearts.

METHODS

CD133 positive cells were isolated from bone marrow by magnetic bead selection. Positive cells (5 - 8 x 10 (6) cells) were transplanted into porcine ischemic myocardium (n = 8). Control animals (n = 3) received a medium injection. MRI on a 7T scanner was performed to demonstrate the distribution of the EPCs.

RESULTS

CD133+ cells were identified on gradient echo images (T(1)-weighted) within the myocardium 4 weeks after transplantation.

CONCLUSIONS

Magnetically labeled EPCs transplanted for therapeutic neovascularization or reduction of infarct size in myocardial ischemia can be visualized by MRI at high-field strengths.

Imaging islets labeled with magnetic nanoparticles at 1.5 Tesla

We have developed a magnetic resonance imaging (MRI) technique for imaging Feridex (superparamagnetic iron oxide [SPIO])-labeled islets of Langerhans using a standard clinical 1.5-Tesla (T) scanner and employing steady-state acquisition imaging sequence (3DFIESTA). Both porcine and rat islets were labeled with SPIO by a transfection technique using a combination of poly-l-lysine and electroporation. Electron microscopy demonstrated presence of SPIO particles within the individual islet cells, including beta-cells and particles trapped between cell membranes. Our labeling method produced a transfection rate of 860 pg to 3.4 ng iron per islet, dependent on the size of the islet. The labeling procedure did not disrupt either the function or viability of the islets. In vitro 3DFIESTA magnetic resonance images of single-labeled islets corresponded with their optical images. In vivo T2*-weighted scan using 1.5 T detected as few as 200 SPIO-labeled islets transplanted under rat kidney capsule, which correlated with immunohistochemistry of the transplant for insulin and iron. Ex vivo 3DFIESTA images of kidneys containing 200, 800 or 2,000 SPIO-labeled islet isografts showed good correlation between signal loss and increasing numbers of islets. These data provide evidence that islets can be labeled with SPIO and imaged using clinically available 1.5- T MRI.

Administered mesenchymal stem cells enhance recovery from ischemia/reperfusion-induced acute renal failure in rats

BACKGROUND

Adult stem cells are promising for the development of novel therapies in regenerative medicine. Acute renal failure (ARF) remains a frequent clinical complication, associated with an unacceptably high mortality rate, in large part due to the ineffectiveness of currently available therapies. The aim of this study was, therefore, to evaluate the therapeutic effectiveness of bone marrow-derived mesenchymal stem cells in a rat model of ischemia/reperfusion (I/R) ARF.

METHODS

We used a common I/R model in rats to induce ARF by clamping both renal pedicles for 40 minutes. Mesenchymal stem cells were iron-dextran-labeled for in vivo tracking studies by magnetic resonance imaging (MRI) and kidneys were imaged for mesenchymal stem cells immediately after infusion and at day 3 after ARF. Renal injury was scored on day 3 and cells were additionally tracked by Prussian blue staining.

RESULTS

We show in I/R-induced ARF in rats, modeling the most common form of clinical ARF, that infusion of mesenchymal stem cells enhances recovery of renal function. Mesenchymal stem cells were found to be located in the kidney cortex after injection, as demonstrated by MRI. Mesenchymal stem cells-treated animals had both significantly better renal function on days 2 and 3 and better injury scores at day 3 after ARF. Histologically, mesenchymal stem cells were predominantly located in glomerular capillaries, while tubules showed no iron labeling, indicating absent tubular transdifferentiation.

CONCLUSION

We conclude that the highly renoprotective capacity of mesenchymal stem cells opens the possibility for a cell-based paradigm shift in the treatment of I/R ARF.

Iron dextran causes renal iron deposition but not renal dysfunction in angiotensin II-treated and untreated rats

BACKGROUND

Angiotensin II infusion into rats causes iron deposition in the kidney, which may augment the pro-proteinuric effects of this octapeptide. We have investigated whether administration of iron mimics the renal damage induced by angiotensin II.

METHODS

Rats were treated with iron dextran at a total dose of 960 mg/kg either with or without angiotensin II treatment at a dose of 0.7 mg/kg/day for 7 days. Protein expression of ferritin and heme oxygenase-1, an oxidative stress-sensitive gene, was determined by Western blot analysis and immunohistochemistry.

RESULTS

Administration of iron dextran did not significantly increase proteinuria or decrease creatinine clearance in the rats with or without angiotensin II treatment. Prussian blue staining showed that iron deposition was observed mainly in the glomerular and medullar regions in the iron dextran-treated rats, but in the tubular epithelial cells in angiotensin II-infused rats. Administration of iron dextran upregulated ferritin, but not heme oxygenase-1.

CONCLUSION

Iron dextran did not enhance or cause the renal dysfunction in the angiotensin II-treated or untreated rats, respectively. The distribution of deposited iron and presumably the type of iron compound administered may be important determinants of the development of renal injury.

Preparation of immunomagnetic iron-dextran nanoparticles and application in rapid isolation of E.coli O157:H7 from foods

AIM: To prepare a kind of magnetic iron-dextran nanoparticles that was coated with anti-E.coli O157:H7 IgG, analyze its application conditions, and try to use it to isolate E.coli O157:H7 from foods.

METHODS: Magnetic iron-dextran nanoparticles were prepared by the reaction of a mixture of ferric and ferrous ions with dextran polymers under alkaline conditions. The particles were coated with antiserum against E.coli O157:H7 by the periodate oxidation-borohydride reduction procedure. The oxidation time, amount of antibody coating the particles, amount of nanoparticles, incubation time and isolation time were varied to determine their effects on recovery of the organisms. Finally, the optimum conditions for isolating E.coli O157:H7 from food samples were established.

RESULTS: E.coli O157:H7 can be isolated from samples within 15 min with the sensitivity of 10¹ CFU/mL or even less. In the presence of 10⁸ CFU/mL of other organisms, the sensitivity is 10¹-10² CFU/mL. Nonspecific binding of other bacteria to the particles was not observed. Two and a half hours of enrichment is enough for the particles to detect the target from the food samples inoculated with 1 CFU/g.

CONCLUSION: Isolation of target bacteria by immuno-magnetic nanoparticles is an efficient method with high sensitivity and specificity. The technique is so simple that it can be operated in lab and field even by untrained personnel.

Iron overload augments angiotensin II-induced cardiac fibrosis and promotes neointima formation

BACKGROUND

Abnormal iron deposition may cause oxidant-induced damage in various organs. We have previously reported that continuous administration of angiotensin II to rats results in an overt iron deposition in the renal tubular epithelial cells, which may have a role in angiotensin II-induced renal damage. In the present study, we investigated the role of iron in the development of cardiac injury induced by angiotensin II.

METHODS AND RESULTS

Angiotensin II was continuously infused to rats at a dose of 0.7 mg/kg per day for 7 consecutive days. No iron deposits were observed in the hearts of untreated rats, whereas iron deposition was seen in the cells in the subepicardial and granulation regions after angiotensin II infusion. Concomitant administration of deferoxamine, an iron chelator, significantly reduced the extent of cardiac fibrosis, which suggests that iron deposition aggravates the cardiac fibrosis induced by angiotensin II. Iron overload caused by the administration of iron-dextran resulted in an augmentation of cardiac fibrosis and the generation of neointimal cells in the coronary artery in angiotensin II-infused rats. By contrast, neointima was not formed in the cardiac vessels in norepinephrine-infused rats with iron overload.

CONCLUSIONS

Cardiac iron deposition may be involved in the development of cardiac fibrosis induced by angiotensin II. In addition, iron overload may enhance the formation of neointima under conditions of increased circulating angiotensin II but not catecholamines.

Stearoyl coenzyme A desaturase 1 expression and activity are increased in the liver during iron overload

In humans, hepatic iron overload can lead to hepatocellular carcinoma development. Iron related dysregulation of hepatic genes could play a role in this phenomenon. We previously found that the carbonyl-iron overloaded mouse was a useful model to study the mechanisms involved in the development of hepatic lesions related to iron excess. The aim of the present study was to identify hepatic genes overexpressed in conditions of iron overload by using this model. A suppressive subtractive hybridization was performed between hepatic mRNAs extracted from control and 3% carbonyl-iron overloaded mice during 8 months. This methodology allowed us to identify stearoyl coenzyme A desaturase 1 (SCD1) mRNA overexpression in the liver of iron loaded mice. The corresponding enzymatic activity was also found to be significantly increased. In addition, we demonstrated that both SCD1 mRNA expression and activity were increased in another iron overload model in mice obtained by a single iron-dextran subcutaneous injection. Moreover, we found, in both models, that SCD1 mRNA was not only influenced by the quantity of iron in the liver but also by the duration of iron overload since SCD1 mRNA upregulation was not detected in earlier stages of iron overload. In addition, we found that cellular repartition likely influenced SCD1 mRNA expression. In conclusion, we demonstrated that iron excess in the liver induced both the expression of SCD1 mRNA and its corresponding enzymatic activity. The level and duration of iron overload, as well as cellular repartition of iron excess in the liver likely play a role in this induction. The fact that the expression and activity of SCD1, an enzyme adding a double bound into saturated fatty acids, are induced in two models of iron overload in mice leads to the conclusion that iron excess in the liver may enhance the biosynthesis of unsaturated fatty acids.

Vitamin C suppresses oxidative lipid damage in vivo, even in the presence of iron overload

Ascorbate is a strong antioxidant; however, it can also act as a prooxidant in vitro by reducing transition metals. To investigate the in vivo relevance of this prooxidant activity, we performed a study using guinea pigs fed high or low ascorbate doses with or without prior loading with iron dextran. Iron-loaded animals gained less weight and exhibited increased plasma beta-N-acetyl-D-glucosaminidase activity, a marker of tissue lysosomal membrane damage, compared with control animals. The iron-loaded animals fed the low ascorbate dose had decreased plasma alpha-tocopherol levels and increased plasma levels of triglycerides and F(2)-isoprostanes, specific and sensitive markers of in vivo lipid peroxidation. In contrast, the two groups of animals fed the high ascorbate dose had significantly lower hepatic F(2)-isoprostane levels than the groups fed the low ascorbate dose, irrespective of iron load. These data indicate that 1) ascorbate acts as an antioxidant toward lipids in vivo, even in the presence of iron overload; 2) iron loading per se does not cause oxidative lipid damage but is associated with growth retardation and tissue damage, both of which are not affected by vitamin C; and 3) the combination of iron loading with a low ascorbate status causes additional pathophysiological changes, in particular, increased plasma triglycerides.

Iron-overload cardiomyopathy: evidence for a free radical--mediated mechanism of injury and dysfunction in a murine model

Iron-overload cardiomyopathy is a restrictive cardiomyopathy that manifests itself as systolic or diastolic dysfunction secondary to increased deposition of iron in the heart and occurs with common genetic disorders such as primary hemochromatosis and beta-thalassemia major. Although the exact mechanism of iron-induced heart failure remains to be elucidated, the toxicity of iron in biological systems is believed to be attributed to its ability to catalyze the generation of oxygen-free radicals. In the current investigation, the dose-dependent effects of chronic iron-loading on heart tissue concentrations of iron, glutathione peroxidase (GPx) activity, free-radical production, and cardiac dysfunction were investigated in a murine model of iron-overload cardiomyopathy. It was shown that chronic iron-overload results in dose-dependent (a) increases in myocardial iron burden, (b) decreases in the protective antioxidant enzyme GPx activity, (c) increased free-radical production, and (d) increased mortality. These findings show that the mechanism of iron-induced heart dysfunction involves in part free radical-mediated processes.

The haemolytic activity of an iron carbohydrate complex

The haemolytic activity of iron-dextran complex is found to be a function of time, temperature, pH, and concentration. The lytic action is enhanced by small amounts of added ferrous sulphate. The lytic action is inhibited by chelating agents such as citrate and sequestrene salts, which bind ionic iron, but not by ferric citrate or ferric sequestrene which do not bind iron. The ionised iron content of iron-dextran is deduced. The lytic activity of iron-dextran is also inhibited by iron-dextrin and by an iron-sorbitol-citric acid preparation. It is suggested that the iron-sorbitol-citrate molecular complex contains free chelating groups for iron. The significance of these findings for iron-carbohydrate toxicity and metabolism is briefly discussed.

Studies on a new intramuscular haematinic, iron-sorbitol

A new iron preparation for intramuscular use is described. It contains a complex of iron, sorbitol and citric acid. Its properties in comparison with several other complexes, particularly iron-dextran, have been studied. The preparation is stable in serum, is hypertonic, does not produce haemolysis, and affects coagulation only at very high concentrations, such as are reached only in vitro. Absorption from muscle takes place very rapidly; two-thirds of the iron is removed within 3 hr, and there is a very rapid increase in the serum-iron concentration. In experimental animals, the maximum level is reached after about 20 min and in man after about 2 hr. Disappearance from the serum takes place rapidly. The preparation contains a small amount of a fraction which reacts with transferrin and is dialysable. In man, about 30% of the total dose of iron is excreted through the kidneys during the first 24 hr after injection, the greater part of the excretion taking place during the first few hours.

The toxic effects of iron-dextran complex on mammalian cells in tissue culture

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[Protection of vitamin E against testis lipid peroxidation induced by iron and ethanol]

The influence of acute iron and ethanol load on lipid peroxidation and antioxidative defense systems in rat testes and the modification after supplemented with Vitamin E was investigated. Acute iron and ethanol load was achieved by i.p. injection of iron-dextran (500 mg/kg) and ethanol (50 mmol/kg). After 18 h, a significant increase in testis total iron content was induced. Compared with control, total testis iron content was 6.8-fold higher in iron-treated rats and 9.1-fold in iron and ethanol treated rats. As the content of iron increasing, the endogenous lipid peroxidation evaluated as 2-thiobarbituric acid-rective substances (TBARS) increased apparently, and the content of lipid-soluble antioxidants alpha-tocopherol decreased. The supplement of an antioxidant, alpha-tocopherol, protected against lipid peroxidation. Iron and ethanol treatment did not affect the activity of superoxide dismutase, catalase and glutathione peroxidase. The results indicate that acute iron load causes iron accumulation in rat testes and ethanol increases the same accumulation. Iron played pivotal paracrine roles on ethanolinduced injure rat testis. The supplement of Vitamin E can protect against this damage.

MORPHOLOGICAL EFFECTS OF IRON-DEXTRAN ON FOWL FIBROCYTES IN VITRO

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