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1.
Transl Anim Sci ; 4(1): 452-459, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32705003

ABSTRACT

Long distance transportation can be a significant source of stress to cattle and is associated with increased risk of bovine respiratory disease (BRD). The administration of a nonsteroidal anti-inflammatory drug (NSAID) has been shown to reduce stress following long distance transport. The objective of this study was to compare performance, health, accelerometer activity, and well-being between calves receiving either tildipirosin (Zuprevo 18%; Merck Animal Health, Madison, NJ) alone or in combination with transdermal flunixin (BANAMINE Transdermal Pour-on Solution; Merck Animal Health, Madison, NJ) on arrival at the feedlot. Three hundred eighty-four polled, Continental × English, and English crossbred bulls (n = 199) and steers (n = 185) were enrolled into one of two treatments: 1) tildipirosin administered in the neck as a single dose of 4 mg/kg only (PLBO) 2) tildipirosin in combination with transdermal flunixin applied to the dorsal midline at a dose of 3.3 mg/kg (FTD). Outcomes measured were average daily gain (ADG), dry mater intake (DMI), gain to feed, morbidity, mortality, accelerometer activity data, and a daily visual analog scale (VAS) assessment of well-being. Body weight (BW) was determined by weighing individual animals; ADG was calculated as initial BW-final BW / total days on feed; DMI was calculated as daily pen feed allocation-feed remaining at next feeding / number of calves in the pen; and gain to feed was calculated as pen level ADG / pen level DMI. The VAS used was a 100 mm line anchored at each end by descriptors of "no pain" or "severe pain". Statistical analysis was performed using JMP 13 computer software using pen as the experimental unit, lot number as a random variable, and treatment as a fixed variable. There was no treatment effect on DMI (P = 0.51). During the first 14 d on feed, FTD calves had a lower ADG of 0.90 kg/d compared with 1.33 kg/d in the PLBO group (P = 0.05). There were no differences observed in morbidity and mortality between groups (P = 0.29). There were no treatment differences from activity data (P = 0.19). The VAS assessment showed a significant time × treatment interaction (P < 0.001). During the first 36 h after treatment administration, the FTD-treated calves had lower VAS scores [6.23 (95% CI: 5.27-7.20) compared with 7.28 (95% CI: 6.32-8.24)] than PLBO (P < 0.05). Results suggest that FTD-treated calves showed less signs of pain the first 36 h postdrug application relative to PLBO calves.

2.
Child Abuse Negl ; 96: 104101, 2019 10.
Article in English | MEDLINE | ID: mdl-31377534

ABSTRACT

BACKGROUND: Despite the importance of child sexual abuse (CSA) prevention, there are few recent randomized controlled trials of school-based CSA prevention programs. OBJECTIVES: (1) To evaluate the effects of the Second Step Child Protection Unit (CPU) on students' CSA prevention concept knowledge, ability to recognize, report, and refuse unsafe touches, and perceptions of teacher-student relations and (2) investigate the moderating role of age and gender on program effectiveness. PARTICIPANTS AND SETTING: Eight elementary schools in a large suburban school district in the northeast United States were randomly assigned to the intervention or control condition, with analyses conducted on a total of 2172 students. METHODS: Students in intervention schools received the 6-week CPU and those in the control schools were exposed to business as usual. Students were administered assessments at baseline and then at post-test. RESULTS: Univariate Analyses of Covariance revealed that students in the intervention schools had significantly higher scores on all outcomes than students in the control schools at post-test, even after controlling for baseline scores. Children in younger grades made greater gains from the program, and girls scored higher than boys in CSA knowledge and ability to recognize, refuse, and report unsafe touches, but both boys and girls made significant gains. CONCLUSIONS: Results support the importance of beginning early with school-based CSA prevention efforts. Although boys are still at a relative disadvantage in terms of their knowledge and ability in this area, they are able to make gains at the same rate as girls.


Subject(s)
Child Abuse, Sexual/prevention & control , School Health Services , Child , Child, Preschool , Female , Health Education , Humans , Male , New England , Program Evaluation , Schools , Sex Factors , Students
3.
Inorg Chem ; 56(14): 7788-7802, 2017 Jul 17.
Article in English | MEDLINE | ID: mdl-28644630

ABSTRACT

The recent X-ray structure of titanium(IV)-bound human serum transferrin (STf) exhibiting citrate as a synergistic anion reveals a difference in Ti(IV) coordination versus iron(III), the metal endogenously delivered by the protein to cells. This finding enriches our bioinspired drug design strategy for Ti(IV)-based anticancer therapeutics, which applies a family of Fe(III) chelators termed chemical transferrin mimetic (cTfm) ligands to inhibit Fe bioavailability in cancer cells. Deferasirox, a drug used for iron overload disease, is a cTfm ligand that models STf coordination to Fe(III), favoring Fe(III) binding versus Ti(IV). This metal affinity preference drives deferasirox to facilitate the release of cytotoxic Ti(IV) intracellularly in exchange for Fe(III). An aqueous speciation study performed by potentiometric titration from pH 4 to 8 with micromolar levels of Ti(IV) deferasirox at a 1:2 ratio reveals exclusively Ti(deferasirox)2 in solution. The predominant complex at pH 7.4, [Ti(deferasirox)2]2-, exhibits the one of the highest aqueous stabilities observed for a potent cytotoxic Ti(IV) species, demonstrating little dissociation even after 1 month in cell culture media. UV-vis and 1H NMR studies show that the stability is unaffected by the presence of biomolecular Ti(IV) binders such as citrate, STf, and albumin, which have been shown to induce dissociation or regulate cellular uptake and can alter the activity of other antiproliferative Ti(IV) complexes. Kinetic studies on [Ti(deferasirox)2]2- transmetalation with Fe(III) show that a labile Fe(III) source is required to induce this process. The initial step of this process occurs on the time scale of minutes, and equilibrium for the complete transmetalation is reached on a time scale of hours to a day. This work reveals a mechanism to deliver Ti(IV) compounds into cells and trigger Ti(IV) release by a labile Fe(III) species. Cellular studies including other cTfm ligands confirm the Fe(III) depletion mechanism of these compounds and show their ability to induce early and late apoptosis.


Subject(s)
Antineoplastic Agents/pharmacology , Benzoates/pharmacology , Coordination Complexes/pharmacology , Iron Chelating Agents/pharmacology , Triazoles/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Benzoates/chemical synthesis , Benzoates/chemistry , Cell Line, Tumor , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Deferasirox , Drug Design , Drug Stability , Humans , Iron/chemistry , Iron Chelating Agents/chemical synthesis , Iron Chelating Agents/chemistry , Ligands , Models, Chemical , Molecular Structure , Serum Albumin/chemistry , Titanium/chemistry , Transferrin/chemistry , Triazoles/chemical synthesis , Triazoles/chemistry
4.
J Am Chem Soc ; 138(17): 5659-65, 2016 05 04.
Article in English | MEDLINE | ID: mdl-27070073

ABSTRACT

Human serum transferrin (sTf) is a protein that mediates the transport of iron from blood to cells. Assisted by the synergistic anion carbonate, sTf transports Fe(III) by binding the metal ion in a closed conformation. Previous studies suggest sTf's role as a potential transporter of other metals such as titanium. Ti is a widely used metal in colorants, foods, and implants. A substantial amount of Ti is leached into blood from these implants. However, the fate of the leached Ti and its transport into the cells is not known. Understanding Ti interaction with sTf assumes a greater significance with our ever increasing exposure to Ti in the form of implants. On the basis of in vitro studies, it was speculated that transferrin can bind Ti(IV) assisted by a synergistic anion. However, the role and identity of the synergistic anion(s) and the conformational state in which sTf binds Ti(IV) are not known. Here we have solved the first X-ray crystal structure of a Ti(IV)-bound sTf. We find that sTf binds Ti(IV) in an open conformation with both carbonate and citrate as synergistic anions at the metal binding sites, an unprecedented role for citrate. Studies with cell lines suggest that Ti(IV)-sTf is transported into cells and that sTf and citrate regulate the metal's blood speciation and attenuate its cytotoxic property. Our results provide the first glimpse into the citrate-transferrin synergism in the regulation of Ti(IV) bioactivity and offers insight into the future design of Ti(IV)-based anticancer drugs.


Subject(s)
Citric Acid/chemistry , Titanium/chemistry , Transferrin/chemistry , Biological Transport , Carbon-13 Magnetic Resonance Spectroscopy , Crystallography, X-Ray , Humans , Molecular Conformation , Titanium/toxicity
5.
Inorg Chem ; 53(3): 1743-9, 2014 Feb 03.
Article in English | MEDLINE | ID: mdl-24422475

ABSTRACT

As an endogenous serum protein binder of Ti(IV), transferrin (Tf) serves as an excellent vehicle to stabilize the hydrolysis prone metal ion and successfully transport it into cells. This transporting role is thought to be central to Ti(IV)'s anticancer function, but efforts to synthesize Ti(IV) compounds targeting transferrin have not produced a drug. Nonetheless, the Ti(IV) transferrin complex (Ti2Tf) greatly informs on a new Ti(IV)-based anticancer drug design strategy. Ti2Tf interferes with cellular uptake of Fe(III), which is particularly detrimental to cancer cells because of their higher requirement for iron. Ti(IV) compounds of chemical transferrin mimetic (cTfm) ligands were designed to facilitate Ti(IV) activity by attenuating Fe(III) intracellular levels. In having a higher affinity for Fe(III) than Ti(IV), these ligands feature the appropriate balance between stability and lability to effectively transport Ti(IV) into cancer cells, release Ti(IV) via displacement by Fe(III), and deplete the intracellular Fe(III) levels. The cTfm ligand N,N'-di(o-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid (HBED) was selected to explore the feasibility of the design strategy. Kinetic studies on the Fe(III) displacement process revealed that Ti(IV) can be transported and released into cells by HBED on a physiologically relevant time scale. Cell viability studies using A549 cancerous and MRC5 normal human lung cells and testing the cytotoxicity of HBED and its Ti(IV), Fe(III), and Ga(III) compounds demonstrate the importance of Fe(III) depletion in the proposed drug design strategy and the specificity of the strategy for Ti(IV) activity. The readily derivatized cTfm ligands demonstrate great promise for improved Ti(IV) anticancer drugs.


Subject(s)
Antineoplastic Agents/chemistry , Biomimetic Materials/chemistry , Drug Design , Ferric Compounds/metabolism , Titanium/chemistry , Transferrin/chemistry , Antineoplastic Agents/pharmacology , Binding Sites , Biomimetic Materials/pharmacology , Biomimetics , Cell Line , Cell Line, Tumor , Cell Survival/drug effects , Humans , Neoplasms/drug therapy , Titanium/pharmacology , Transferrin/pharmacology
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