HEALTH BELIEF APPLICATION MODEL: KNOWLEDGE AND PATTERNS OF IRON SOURCE FOOD CONSUMPTION AS A PREVENTIVE EFFORT FOR ANEMIA EVENTS

ABSTRACT Female adolescents are prone to iron deficiency anemia due to regular menstrual cycles and loss of basal, thus requiring sufficient iron intake from food consumed daily. The concept of the Health Belief Model which consists of perceived susceptibility, perceived severity, perceived benefit, perceived barrier, and self efficacy helps to take action on the prevention of anemia. This study aimed to analyze the correlation of knowledge, the Health Belief Model, and consumption patterns with anemic status at Saint Stanislaus High School. This study used a cross-sectional design. The population in this study were all female students in grade X and XI of Saint Stanislaus Senior High School, totaling 84 people. The cluster random sampling technique was used to calculate the total amount of samples, totaling 46 people as the sample of this study. The data collected included respondent characteristics, knowledge rate, construction of Health Belief Model, consumption patterns of iron source foods differentiated into levels of adequacy and frequency of eating, and anemia status. The results of this study showed that 14 of the respondents aged 16 years experienced anemia (30.43%). The correlation of knowledge and the incidence of anemia significantly correlated, with a p-value of 0.044 (p <0.005). Meanwhile, constructs of the Health Belief Model and the level of adequacy of food consumption of iron sources had no correlation with the incidence of anemia (p> 0.005). The frequency of kale consumption as a source of non heme iron had a correlation with the incidence of anemia (p <0.005). This study concluded that there was a correlation with knowledge and the incidence of anemia in Saint Stanislaus High School students. Proper nutrition education based on the concept of the Health Belief Model can be given to students to let them have an understanding, good attitude, and practice prevention measures for anemia well. Keywords: knowledge, Health Belief Model, iron consumption pattern, anemic

Ferric Citrate Uptake is a Virulence Factor in Uropathogenic Escherichia coli

More than half of women will experience a urinary tract infection (UTI) with uropathogenic Escherichia coli (UPEC) causing ~80% of uncomplicated cases. Iron acquisition systems are essential for uropathogenesis, and UPEC encode functionally redundant iron acquisition systems, underlining their importance. However, a recent UPEC clinical isolate, HM7 lacks this functional redundancy and instead encodes a sole siderophore, enterobactin. To determine if E. coli HM7 possesses unidentified iron acquisition systems, we performed RNA-sequencing under iron-limiting conditions and demonstrated that the ferric citrate uptake system (fecABCDE and fecIR) was highly upregulated. Importantly, there are high levels of citrate within urine, some of which is bound to iron, and the fec system is highly enriched in UPEC isolates compared to environmental or fecal strains. Therefore, we hypothesized that HM7 and other similar strains use the fec system to acquire iron in the host. Deletion of both enterobactin biosynthesis and ferric citrate uptake (ΔentB/ΔfecA) abrogates use of ferric citrate as an iron source and fecA provides an advantage in human urine in absence of enterobactin. However, in a UTI mouse model, fecA is a fitness factor independent of enterobactin production, likely due to the action of host Lipocalin-2 chelating ferrienterobactin. These findings indicate that ferric citrate uptake is used as an iron source when siderophore efficacy is limited, such as in the host during UTI. Defining these novel compensatory mechanisms and understanding the nutritional hierarchy of preferred iron sources within the urinary tract are important in the search for new approaches to combat UTI.

One-Pot Synthesis of Magnetic Polypyrrole Nanotubes for Adsorption of Cr(VI) in Aqueous Solution

A novel and efficient route is proposed to fabricate Fe3O4/polypyrrole (Fe3O4/PPy) nanotubes via a one-pot process. The one-pot strategy involves the synthesis of Fe3O4/PPy nanotubes by oxidative polymerization of pyrrole (Py) monomer using Fe3+ as an oxidant in the presence of methyl orange (MO) and Fe3+ used as iron source to form Fe3O4 simultaneously in basic conditions without adding any additional iron source and oxidant. The effects of Fe3+ concentration on the morphology and adsorption capacity of the Fe3O4/PPy nanotubes were investigated. The Fe3O4/PPy nanotubes exhibit a tubular structure. Fe3O4 nanoparticles are well dispersed among the PPy nanotubes. The Fe3O4/PPy nanotubes exhibit excellent magnetic property, which make them easy to separate from wastewater by magnetic separation. The diameter of the PPy nanotubes decreased with the increase of the Fe3+ concentration. The Fe3O4/PPy nanotubes showed strong adsorption capability for Cr(VI) with the maximum adsorption capacity of about 451.45 mg·g−1, which is significantly higher than bare Fe3O4 nanoparticles. Cr(VI) was adsorbed on Fe3O4/PPy nanotubes by ion exchange and chelation, where Cr(VI) was partially reduced to Cr(III) due to the existence of −NH+ on the Fe3O4/PPy nanotubes. Furthermore, the Fe3O4/PPy nanotubes are recyclable, retaining 90% of the initial removal efficiency after 5 adsorption/desorption cycles.

Depositional Conditions of Cretaceous Ironstones Deposit in the Chulym-Yenisey Basin (Western Siberia)

This study reconstructs the depositional conditions of ironstones within the Chulym-Yenisey basin and assesses the iron source. The detrital minerals of the studied deposits include quartz and feldspar. The authigenic minerals are goethite, siderite, aragonite, dolomite, calcite, apatite, barite, and pyrite. The clay components include minerals of the chlorite group (possible chamosite), nontronite, kaolinite, illite, and beidellite. Local bacterial sulfate reduction led to the formation of pyrite framboids in siltstone layers. The subsequent diagenetic iron reduction promoted the formation of chamosite from siderite. The goethite precipitation occurred in an oxidic aqueous environment. The Cretaceous continental sediments of the Ilek and Kia Formations of the Chulym-Yenisei depression consist of fine- and medium-grained, cross-stratified, poorly sorted litho-feldspatho-quartzose sandstones of fluvial channel origin alternating with bluish-gray siltstones and ironstones of floodplain–lacustrine–bog origin. Thin layers of iron-bearing rocks within siltstones formed in meromictic waters. The changes in geochemical proxies demonstrate fluctuations of paleoenvironmental conditions within the Cretaceous sequence. Siltstones and sandstones formed under humid and arid conditions, respectively. The primary iron source for sediments of the Chulym-Yenisey depression was determined as volcanogenic and igneous rocks of the Altai-Sayan mountainous region.

The Corynebacterium diphtheriae HbpA hemoglobin-binding protein contains a domain that is critical for hemoprotein-binding, cellular localization and function.

The acquisition of hemin-iron from hemoglobin-haptoglobin (Hb-Hp) by Corynebacterium diphtheriae requires the iron-regulated surface proteins HtaA, ChtA, ChtC, and the recently identified Hb-Hp binding protein HbpA. We previously showed that a purified form of HbpA (HbpA-S), lacking the C-terminal region, was able to bind Hb-Hp. In this study, we show that the C-terminal region of HbpA significantly enhances binding to Hb-Hp. A purified form of HbpA that includes the C-terminal domain (HbpA-FL) exhibits much stronger binding to Hb-Hp than HbpA-S. Size exclusion chromatography (SEC) showed that HbpA-FL as well as HtaA-FL, ChtA-FL, and ChtC-FL exist as high molecular weight complexes, while HbpA-S is present as a monomer, indicating that the C-terminal region is required for formation of large aggregates. Growth studies showed that expression of HbpA-FL in the Δ hbpA mutant restored wild-type levels of growth in low-iron medium that contained Hb-Hp as the sole iron source, while HbpA-S failed to complement the Δ hbpA mutant. Protein localization studies in C. diphtheriae showed that HbpA-FL is present in both in the supernatant and in the membrane fractions, and that the C-terminal region is required for membrane anchoring. Purified HbpA-FL was able to enhance growth of the Δ hbpA mutant when added to culture medium that contained Hb-Hp as a sole iron source, suggesting that secreted HbpA is involved in the use of hemin-iron from Hb-Hp. These studies extend our understanding of this novel Hb-Hp binding protein in this important human pathogen. IMPORTANCE Hemoproteins, such as Hb, are an abundant source of iron in humans and are proposed to be required by numerous pathogens to cause disease. In this report, we expand on our previous studies in further defining the role of HbpA in hemin-iron acquisition in C. diphtheriae . HbpA is unique to C. diphtheriae , and appears to function unlike any previously described bacterial iron-regulated Hb- or Hb-Hp-binding protein. HbpA is both secreted and present in the membrane, and exists as a large aggregate that enhances its ability to bind Hb-Hp and promote hemin-iron uptake. Current studies with HbpA will increase our understanding of iron transport systems in C. diphtheriae .

An exposed outer membrane haemin-binding protein facilitates haemin transport by a TonB-dependent receptor in Riemerella anatipestifer

Iron is an essential element for the replication of most bacteria, including Riemerella anatipestifer (R. anatipestifer, RA), a gram-negative bacterial pathogen of ducks and other birds. R. anatipestifer utilizes haemoglobin-derived haemin as an iron source; however, the mechanism by which this bacterium acquires haemin from haemoglobin is largely unknown. Here, RhuA disruption was shown to impair iron utilization from duck haemoglobin in R. anatipestifer CH-1. Moreover, the putative lipoprotein RhuA was identified as a surface-exposed, outer membrane haemin-binding protein, but it could not extract haemin from duck haemoglobin. Mutagenesis studies showed that recombinant RhuAY144A, RhuAY177A and RhuAH149A lost haemin-binding ability, suggesting that amino acid sites tyrosine 144 (Y144), Y177 and histidine 149 (H149) are crucial for haemin binding. Furthermore, RhuR, the gene adjacent to RhuA, encodes a TonB2-dependent haemin transporter. The function of RhuA in duck haemoglobin utilization was abolished in the RhuR mutant strain, and recombinant RhuA was able to bind the cell surface of R. anatipestifer CH-1ΔRhuA rather than R. anatipestifer CH-1ΔRhuRΔRhuA, indicating that RhuA associates with RhuR to function. The sequence of the RhuR-RhuA haemin utilization locus exhibits no similarity with those of characterized haemin transport systems. Thus, this locus is a novel haemin uptake locus with homologues distributed mainly in the Bacteroidetes phylum. IMPORTANCE In vertebrates, haemin from haemoglobin is an important iron source for infectious bacteria. Many bacteria can obtain haemin from haemoglobin, but the mechanisms of haemin acquisition from haemoglobin differ among bacteria. Moreover, most studies have focused on the mechanism of haemin acquisition from mammalian haemoglobin. In this study, we found that the RhuR-RhuA locus of R. anatipestifer CH-1, a duck pathogen, is involved in haemin acquisition from duck haemoglobin via a unique pathway. RhuA was identified as an exposed outer membrane haemin-binding protein, and RhuR was identified as a TonB2-dependent haemin transporter. Moreover, the function of RhuA in haemoglobin utilization is RhuR dependent, not vice versa. The homologues of RhuR and RhuA are widely distributed in bacteria in marine environments, animals, and plants, representing a novel haemin transportation system of gram-negative bacteria. This study not only was important for understanding haemin uptake in R. anatipestifer but also enriched the knowledge about the haemin transportation pathway in gram-negative bacteria.