Iron Fortified Complementary Foods Containing a Mixture of Sodium Iron EDTA with Either Ferrous Fumarate or Ferric Pyrophosphate Reduce Iron Deficiency Anemia in 12- to 36-Month-Old Children in a Malaria Endemic Setting: A Secondary Analysis of a Cluster-Randomized Controlled Trial

Iron deficiency anemia (IDA) is a major public health problem in sub-Saharan Africa. The efficacy of iron fortification against IDA is uncertain in malaria-endemic settings. The objective of this study was to evaluate the efficacy of a complementary food (CF) fortified with sodium iron EDTA (NaFeEDTA) plus either ferrous fumarate (FeFum) or ferric pyrophosphate (FePP) to combat IDA in preschool-age children in a highly malaria endemic region. This is a secondary analysis of a nine-month cluster-randomized controlled trial conducted in south-central Côte d'Ivoire. 378 children aged 12-36 months were randomly assigned to no food intervention (n = 125; control group), CF fortified with 2 mg NaFeEDTA plus 3.8 mg FeFum for six days/week (n = 126; FeFum group), and CF fortified with 2 mg NaFeEDTA and 3.8 mg FePP for six days/week (n = 127; FePP group). The outcome measures were hemoglobin (Hb), plasma ferritin (PF), iron deficiency (PF < 30 μg/L), and anemia (Hb < 11.0 g/dL). Data were analyzed with random-effect models and PF was adjusted for inflammation. The prevalence of Plasmodium falciparum infection and inflammation during the study were 44-66%, and 57-76%, respectively. There was a significant time by treatment interaction on IDA (p = 0.028) and a borderline significant time by treatment interaction on iron deficiency with or without anemia (p = 0.068). IDA prevalence sharply decreased in the FeFum (32.8% to 1.2%, p < 0.001) and FePP group (23.6% to 3.4%, p < 0.001). However, there was no significant time by treatment interaction on Hb or total anemia. These data indicate that, despite the high endemicity of malaria and elevated inflammation biomarkers (C-reactive protein or α-1-acid-glycoprotein), IDA was markedly reduced by provision of iron fortified CF to preschool-age children for 9 months, with no significant differences between a combination of NaFeEDTA with FeFum or NaFeEDTA with FePP. However, there was no overall effect on anemia, suggesting most of the anemia in this setting is not due to ID. This trial is registered at clinicaltrials.gov (NCT01634945).

Intraperitoneal pyrophosphate treatment reduces renal calcifications in Npt2a null mice

Mutations in the proximal tubular sodium-dependent phosphate co-transporters NPT2a and NPT2c have been reported in patients with renal stone disease and nephrocalcinosis, however the relative contribution of genotype, dietary calcium and phosphate, and modifiers of mineralization such as pyrophosphate (PPi) to the formation of renal mineral deposits is unclear. In the present study, we used Npt2a^-/- mice to model the renal calcifications observed in these disorders. We observed elevated urinary excretion of PPi in Npt2a^-/- mice when compared to WT mice. Presence of two hypomorphic Extracellular nucleotide pyrophosphatase phosphodiesterase 1 (Enpp1^asj/asj) alleles decreased urine PPi and worsened renal calcifications in Npt2a^-/- mice. These studies suggest that PPi is a thus far unrecognized factor protecting Npt2a^-/- mice from the development of renal mineral deposits. Consistent with this conclusion, we next showed that renal calcifications in these mice can be reduced by intraperitoneal administration of sodium pyrophosphate. If confirmed in humans, urine PPi could therefore be of interest for developing new strategies to prevent the nephrocalcinosis and nephrolithiasis seen in phosphaturic disorders.

Pyrophosphate Supplementation Prevents Chronic and Acute Calcification in ABCC6-Deficient Mice

Soft tissue calcification occurs in several common acquired pathologies, such as diabetes and hypercholesterolemia, or can result from genetic disorders. ABCC6, a transmembrane transporter primarily expressed in liver and kidneys, initiates a molecular pathway inhibiting ectopic calcification. ABCC6 facilitates the cellular efflux of ATP, which is rapidly converted into pyrophosphate (PPi), a major calcification inhibitor. Heritable mutations in ABCC6 underlie the incurable calcification disorder pseudoxanthoma elasticum and some cases of generalized arterial calcification of infancy. Herein, we determined that the administration of PPi and the bisphosphonate etidronate to Abcc6^-/- mice fully inhibited the acute dystrophic cardiac calcification phenotype, whereas alendronate had no significant effect. We also found that daily injection of PPi to Abcc6^-/- mice over several months prevented the development of pseudoxanthoma elasticum-like spontaneous calcification, but failed to reverse already established lesions. Furthermore, we found that the expression of low amounts of the human ABCC6 in liver of transgenic Abcc6^-/- mice, resulting in only a 27% increase in plasma PPi levels, led to a major reduction in acute and chronic calcification phenotypes. This proof-of-concept study shows that the development of both acute and chronic calcification associated with ABCC6 deficiency can be prevented by compensating PPi deficits, even partially. Our work indicates that PPi substitution represents a promising strategy to treat ABCC6-dependent calcification disorders.

Transdermal Delivery of Iron Using Soluble Microneedles: Dermal Kinetics and Safety

Currently, the iron compounds are administered via oral and parenteral routes in patients of all ages, to treat iron deficiency. Despite continued efforts to supplement iron via these conventional routes, iron deficiency still remains the most prevalent nutritional disorder all over the world. Transdermal replenishment of iron is a novel, potential approach of iron replenishment. Ferric pyrophosphate (FPP) was found to be a suitable source of iron for transdermal replenishment. The safety of FPP was assessed in this project by challenging the dermal fibroblast cells with high concentration of FPP. The cell viability assay and reactive oxygen species assay were performed. The soluble microneedle array was developed, incorporated with FPP and the kinetics of free iron in the skin; extracellular fluid following dermal administration of microneedle array was investigated in hairless rats. From the cell based assays, FPP was selected as one of the potential iron sources for transdermal delivery. The microneedles were found to dissolve in the skin fluid within 3 hours of administration. The FPP concentration in the dermal extracellular fluid declined after complete dissolution of the microneedle array. Overall, the studies demonstrated the safety of FPP for dermal delivery and the feasibility of soluble microneedle approach for transdermal iron replenishment therapy.

Anti-plaque and antimicrobial efficiency of different oral rinses in a 3-day plaque accumulation model

The idea of incorporating a mouthrinse with normal tooth brushing could be a useful adjunct to oral hygiene. Despite the principle nature of the toothpaste vehicle, most alcohol-based chemical plaque-control agents have been evaluated and later formulated in the mouthrinse vehicle. The current study was aimed to investigate the persistence of antimicrobial action and plaque inhibitory properties of a new alcohol-free mouthrinse when compared with positive control, chlorhexidine 0.12% and placebo control, physiologic saline solution mouthrinses. The evaluation of the antimicrobial activity was performed by saliva samples collected during the 3 days of usage. The results of this study indicate that this new oral rinse has an equivalent plaque inhibitory action to chlorhexidine, and the plaque inhibitory action of the rinse appears to be derived from a persistence of antimicrobial action in the mouth. Furthermore, no side effects were reported during the study, and the additional benefit of no alcohol presence in the rinse solution.

Peritoneal delivery of sodium pyrophosphate blocks the progression of pre-existing vascular calcification in uremic apolipoprotein-E knockout mice

Chronic kidney disease (CKD) is generally associated with disturbances of mineral and bone metabolism. They contribute to the development of vascular calcification (VC), a strong, independent predictor of cardiovascular risk. Pyrophosphate (PPi), an endogenous inhibitor of hydroxyapatite formation, has been shown to slow the progression of VC in uremic animals. Since in patients with CKD treatment is usually initiated for already existing calcifications, we aimed to compare the efficacy of PPi therapy with that of the phosphate binder sevelamer, using a uremic apolipoprotein-E knockout mouse model with advanced VCs. After CKD creation or sham surgery, 12-week-old female mice were randomized to one sham group and four CKD groups (n = 18-19/group). Treatment was initiated 8 weeks after left nephrectomy allowing prior VC development. Uremic groups received either intraperitoneal PPi (high dose, 1.65 mg/kg or low dose, 0.33 mg/kg per day), oral sevelamer (3 % in diet), or placebo treatment for 8 weeks. Both intima and media calcifications worsened with time in placebo-treated CKD mice, based on both quantitative image analysis and biochemical measurements. Progression of calcification between 8 and 16 weeks was entirely halted by PPi treatment, as it was by sevelamer treatment. PPi did not induce consistent bone histomorphometry changes. Finally, the beneficial vascular action of PPi probably involved mechanisms different from that of sevelamer. Further studies are needed to gain more precise insight into underlying mechanisms and to see whether PPi administration may also be useful in patients with CKD and VC.

[Tolerability of iron preparation Actiferol Fe® in children treated for iron deficiency anemia]

INTRODUCTION

Iron de„ciency anemia is the most frequently occurring anemia during the childhood period. Supplementation with adequate doses of iron remains a basic method of prevention and treatment. The various available products containing iron are characterized by a different degree of patient tolerability. Actiferol Fe® is a micronized, dispersible ferric pyrophosphate which improves its water solubility, and therefore it has better absorption and bioavailability.

AIM OF THE STUDY

The assessment of tolerability of Actiferol Fe® in children who were administered this product to treat or prevent of iron de„ciency anemia. The methods of administration and the incidence of adverse effects were analyzed.

MATERIALS AND METHODS

Eighty children (64 boys and 16 girls) aged from one month to 6 years who met the criteria of an indication to be treated with iron were included into the study. The assessment of selected parameters was based on the questionnaire which included questions about tolerability, method of administration, convenience of usage and adverse e#ects. The questionnaire was „lled in by parents (usually by the mother).

RESULTS

The study indicated that Actiferol Fe® has very good or good tolerability in 87.5% (70/80) of patients - 46.3% (37/80) and 41.2% (33/80), respectively. The most frequent method of administration was in liquid form after dissolving: in water - 31,3% (25/80), in orange juice - 18.8% (15/80) or in milk formulas - in 17.5% (14/80) of patients. The method of administration was assessed as convenient or very convenient by 84% (67/80) of participants. Out of the adverse effects reported, the most frequent were change in the stool consistency into harder, abdominal pain and constipation - in 20% (16/80), 11.25% (9/80), 10% (8/80) cases, respectively. Diarrhea, pain during defecation occurred occasionally. A dark color of the stool was reported by 55% (44/80) of patients. In only one case (1.25%) the parents resigned from the product administration and replaced it with another iron product (no connection with tolerability of the formulation).

CONCLUSION

Actiferol Fe® is a product characterized by good tolerability, convenient usage and mild adverse effects.

[Liposomial iron: a new proposal for the treatment of anaemia in chronic kidney disease]

Iron supplementation is essential for the treatment of anemia in the chronic kidney disease (CKD) population. Liposomial iron is a preparation of ferric pyrophosphate carried within a phospholipidic membrane. Compared to other oral formulations, it is well absorbed from the gut and demonstrates high bioavailability together with a lower incidence of side effects. The aim of our study was to evaluate the effectiveness of treatment with liposomial iron compared to intravenous iron in a CKD population with anemia and iron deficiency. Our study is a single-center, prospective, randomized, fourth-phase study. Enrollment for the study began in October 2011 and CKD 3, 4 and 5 patients were randomized to receive either intravenous iron or liposomial iron in a 1:2 ratio. The primary outcome was set as the increase of hemoglobin from baseline. The secondary outcomes were the reduction of erythropoietin dosage by at least 25% in patients treated with erythropoiesis-stimulating agents and an increase in serum ferritin of 100 ng/ml from baseline values. In the preliminary study, 21 patients were analyzed, 14 of whom were treated with oral liposomial iron and 7 with intravenous iron. The observed increase of hemoglobin at 8 weeks compared to baseline was similar in both groups but was significant in the liposomial group only.

A comparison of the pharmacokinetics of the anticancer MET inhibitor foretinib free base tablet formulation to bisphosphate salt capsule formulation in patients with solid tumors

PURPOSE

This phase I, open-label, randomized, 2-part crossover study assessed the safety, pharmacokinetics and relative bioavailability of single doses of the anticancer MET inhibitor foretinib (formerly known as GSK1363089, EXEL-2880 and XL-880) free base tablet formulation compared to a bisphosphate salt capsule formulation (Part 1), and assessed the safety, efficacy, and pharmacokinetics of the bisphosphate salt capsule administered 3 times a week in cancer patients (Part 2).

PATIENTS AND METHODS

In Part 1, patients were randomized in a crossover manner to receive a single oral dose of foretinib formulated as a bisphosphate salt capsule (240 mg; 183 mg free base equivalent) followed one week later by a single dose of a free base tablet (180 mg), or vice versa where the treatment sequence was reversed. In Part 2, patients self-administered oral doses of bisphosphate salt capsules (200 mg) 3 times a week until disease progression.

RESULTS

Twelve patients with solid tumors were enrolled and completed Part 1, and 10 patients continued into Part 2. Most AEs were mild or moderate in severity. The most common drug-related AEs were fatigue, diarrhea, and nausea. The least-squares (LS) mean total area under the curve was 3144 and 3514 ng*h/mL for the free base tablet and bisphosphate salt capsule, respectively, with a ratio of 0.89 (90% confidence interval, CI: 0.69, 1.16). The LS mean maximal concentration (Cmax) was 81.6 and 98.5 ng/mL for the free base and bisphosphate salt, respectively, with a ratio of 0.83 (90% confidence interval, CI: 0.67, 1.02). The time to reach Cmax was ∼4 h for both formulations. The pharmacokinetics of foretinib were not clinically different between the 2 formulations. Of the 10 patients assessed for efficacy, 3 patients achieved stable disease.

CONCLUSIONS

Foretinib was well tolerated as single doses of both the free base and bisphosphate salt formulations. The pharmacokinetics and relative bioavailability of the 2 formulations were not clinically different. The bisphosphate salt formulation was well tolerated on a 3-times a week dosing schedule, and reached steady-state plasma concentration after 2 weeks.

Efficacy of iron-fortified Ultra Rice in improving the iron status of women in Mexico

BACKGROUND

Universal fortification of staple foods with iron has been widely promoted as a cost-effective strategy to reduce iron deficiency in developing-country populations. Nonetheless, relatively few efficacy trials have been reported to date to demonstrate impact on iron status. The Ultra Rice technology provides a means of delivering fortificant iron via rice.

OBJECTIVE

The objective of this study was to test the efficacy of rice fortified with microencapsulated, micronized iron pyrophosphate to improve the iron status of women in Mexico in a randomized, controlled intervention trial.

METHODS

Nonpregnant, nonlactating women 18 to 49 years of age were recruited from six factories. The women received a daily portion of cooked rice 5 days per week for a period of 6 months, before and after which iron status indicators were determined in venous blood samples.

RESULTS

The average intake of iron from the fortificant was 13 mg/day. Mean plasma ferritin concentration and estimated body iron stores were significantly higher, and transferrin receptors were lower, in the iron-fortified rice group following the intervention. Mean hemoglobin concentration also increased in the treatment group, but the increase was significant only when the analysis was restricted to those with baseline hemoglobin < 12.8 g/dL. The absolute reduction in anemia and iron deficiency was 10.3 and 15.1 percentage points, respectively. Total iron intake from fortificant was a significant covariate of change in body iron stores. The overall prevalence of anemia was reduced by 80%.

CONCLUSIONS

Fortification of rice with iron using this technology is an efficacious strategy for preventing iron deficiency.

Dual targeting of tumor vasculature: combining Avastin and vascular disrupting agents (CA4P or OXi4503)

BACKGROUND

This study evaluated the therapeutic efficacy of combining vascular disrupting agents with antiangiogenic agents.

MATERIALS AND METHODS

Human clear cell renal carcinoma (Caki-1) tumors were established in nude mice. Treatments consisted of Avastin (2 mg/kg) administered twice a week; CA4P (100 mg/kg) or OXi4503 (25 mg/kg) administered 3 times a week for a period of 2 weeks; or a combination of Avastin and CA4P or OXi4503. Tumor response was assessed by growth delay.

RESULTS

The tumor growth delays were 8, 6, and 18 days for Avastin, CA4P, and OXi4503, respectively. When the two therapies were combined, there was a significantly greater tumor response than what was achieved with single-agent treatments. For example, Avastin plus CA4P led to a growth delay of 13 days, and 27 days for Avastin plus OXi4503.

CONCLUSION

Vascular-directed therapies that include both antiangiogenic and vascular disrupting therapeutics can result in significantly enhanced antitumor effects.

Vascular targeting agent Oxi4503 inhibits tumor growth in a colorectal liver metastases model

BACKGROUND AND AIM

Oxi4503 is a potent vascular targeting agent belonging to the family of combretastatins. These agents produce an acute reduction in tumor blood flow leading to tumor necrosis. Despite evidence of its efficacy in certain malignancies, the effect on colorectal liver metastases remains largely unknown. This study investigates the effect of Oxi4503 on colorectal liver metastases in a murine model.

METHODS

The effect of a single dose of Oxi4503 on established tumors in a murine model of colorectal liver metastases was assessed following administration of 1-50 mg/kg Oxi4503. In addition, the effects of continuous, daily and intermittent dosing (1-5 mg/kg) on tumor necrosis and growth were studied by quantitative histological and stereological analysis. The effect of multiple dosing on long-term survival was also assessed using the Kaplan-Meier analysis. The microvascular effects of therapy were studied by scanning electron microscopy of microvascular resin casts.

RESULTS

A single dose of 5 or 50 mg/kg of Oxi4503 produced significant tumor necrosis compared to the controls. Subcutaneous continuous dosing infusion with Oxi4503 at 1 mg/kg/day reduced tumor growth compared to the controls, but was associated with marked systemic toxicity. Daily administration over 21 days was associated with significant mortality. Intermittent dosing of Oxi4503 (two doses, 3 days apart) produced the greatest reduction in tumor growth with minimal toxicity and conferred a significant survival advantage. Microvascular casts demonstrated significant disruption of tumor vessels.

CONCLUSIONS

A single dose of Oxi4503 produced significant necrosis and microvascular injury in colorectal liver metastases. Intermittent dosing with Oxi4503 produced the maximum reduction in tumor growth, minimal toxicity, and a significant improvement in survival. Oxi4503 is a potential anticancer agent. Further research into its mechanism of action and its synergistic use with other therapies is warranted.

Taste and acceptance of pyrophosphates by rats and mice

The palatability and taste quality of pyrophosphates were evaluated in a series of behavioral and electrophysiological experiments. In two-bottle choice tests with water, rats strongly preferred some concentrations of Na3HP2O7 and Na4P2O7, moderately preferred some concentrations of K4P2O7 and Fe4(P2O7)3, and were indifferent to or avoided all concentrations of Ca2P2O7 and Na2H2P2O7. The contribution of sodium to the preference for sodium pyrophosphates was ascertained: 1) Rats with a choice between Na4P2O7 and NaCl preferred 1 mM Na4P2O7 to 4 mM NaCl but preferred 40 or 150 mM NaCl to 10 mM Na4P2O7, 2) blocking salt taste transduction by mixing Na4P2O7 with amiloride reduced preferences but did not eliminate them, and 3) three mouse strains (FVB/J, C57BL/6J, and CBA/J) known to differ in sodium preference had the same rank order of preferences for Na3HP2O7 and NaCl, but peak preferences were higher for Na3HP2O7 than for NaCl. The taste qualities of pyrophosphates were determined by measuring taste-evoked responses of neurons in the nucleus of the solitary tract of rats. Across-neuron patterns of activity for sodium pyrophosphates were similar to that of NaCl but the pattern of Na3HP2O7 plus amiloride was unique from those of sweet, salty, sour, bitter, and umami stimuli. Taken together, the results indicate that the high palatability of some concentrations of Na3HP2O7 and Na4P2O7 is due partially to their salty taste, but there must also be another cause, which may include a novel orosensory component distinct from the five major taste qualities.

Effects of toothbrush size and dentifrice type/brand on pea-sized and larger amounts of dentifrice

PURPOSE

To assess the effects of toothbrush size and dentifrice type/brand on amounts of dentifrice being placed when trying to replicate pictures with different amounts of dentifrice, including a pea-sized amount.

METHODS

This laboratory trial used one researcher to repeatedly dispense five dentifrice products on three different child-sized toothbrushes using a standard procedure. Two sets of drawings, depicting the recommended pea-sized and larger amounts, were used as guides in an effort to place the same amount each time. Data were analysed using ANOVA.

RESULTS

Amounts of dentifrice placed on the two larger toothbrushes were significantly greater than those placed on the smallest toothbrush (p < 0.0001). The amounts placed on the two larger toothbrushes with similar brushing areas but different shapes were not significantly different from each other. The effect of dentifrice type/brand varied in each analysis. For pea-sized amounts, one of 10 pairwise comparisons was significant. For amounts larger than pea-sized, another pair of the 10 pairwise comparisons was significant. However, there was no significant effect of dentifrice type/brand when considering both pea-sized and larger amounts together in the same analysis.

CONCLUSIONS

Toothbrush size significantly affected the amount of dentifrice placed for both pea-sized and larger amounts. The amounts placed on larger size toothbrushes were greater than on the smaller size toothbrush. No consistent effects of selected dentifrices were found.

A comparison of two chlorhexidine gel brushing regimens and a conventional toothpaste brushing regimen for the development of tooth staining over a 6-week period

AIMS

A single-centre, randomized single-blind parallel study was undertaken to compare staining seen with three brushing regimens and to determine subject perception of side effects such as staining and effects on taste.

METHODS

This 6-week parallel study used 157 volunteers who were randomized into one of three treatment groups: (i) brushing in the morning and evening with a normal dose of a 1% chlorhexidine gel, (ii) brushing with a low dose of chlorhexidine gel in the evening and a whitening dentifrice in the morning, and (iii) brushing with a standard fluoride paste in the morning and evening. Following home usage of their allocated products, the study volunteers returned after 3 and 6 weeks to record the amount of stain present. After the 6-week period, subject perception of taste and stain acceptability was determined using a questionnaire.

RESULTS

After 6 weeks of use of the low-dose chlorhexidine gel and whitening dentifrice, significantly more stain was seen compared with the use of a standard dentifrice (P<0.0001). Similarly, significantly more stain was seen with use of the normal-dose chlorhexidine gel compared with the low-dose gel and whitening dentifrice (P=0.0007). Approximately 30% of individuals on the low-dose chlorhexidine gel regimen found the amount of stain unacceptable and 10% noted an effect on their taste perception.

CONCLUSIONS

The use of low dose of chlorhexidine gel at night and a whitening paste in the morning produced a significant amount of stain that 30% of subjects considered unacceptable.

Extruded rice fortified with micronized ground ferric pyrophosphate reduces iron deficiency in Indian schoolchildren: a double-blind randomized controlled trial

BACKGROUND

Iron fortification of rice could be an effective strategy for reducing iron deficiency anemia in South Asia.

OBJECTIVE

We aimed to determine whether extruded rice grains fortified with micronized ground ferric pyrophosphate (MGFP) would increase body iron stores in children.

DESIGN

In a double-blind, 7-mo, school-based feeding trial in Bangalore, India, iron-depleted, 6-13-y-old children (n = 184) were randomly assigned to receive either a rice-based lunch meal fortified with 20 mg Fe as MGFP or an identical but unfortified control meal. The meals were consumed under direct supervision, and daily leftovers were weighed. All children were dewormed at baseline and at 3.5 mo. Iron status and hemoglobin were measured at baseline, 3.5 mo, and 7 mo.

RESULTS

At baseline, the prevalences of iron deficiency and iron deficiency anemia in the total sample were 78% and 29%, respectively. After 7 mo of feeding, there was a significant increase in body iron stores in both study groups (P < 0.001), with a greater increase in the iron group than in the control group (P < 0.05). There was a significant time x treatment interaction for iron deficiency, which fell from 78% to 25% in the dewormed iron group and from 79% to 49% in the dewormed control group. Iron deficiency anemia decreased from 30% to 15% (NS) in the iron group but remained virtually unchanged in the control group (28% and 27%). In sensory tests, the MGFP-fortified rice (fortified at 3 and 5 mg Fe/100 g) was indistinguishable from natural rice, in both cooked and uncooked form.

CONCLUSIONS

Extruded rice fortified with MGFP has excellent sensory characteristics. Fed in a school lunch meal, it increases iron stores and reduces the prevalence of iron deficiency in Indian children.

In-vivo effects of fluoridated antiplaque dentifrice and bonding material on enamel demineralization adjacent to orthodontic appliances

INTRODUCTION

The effect of a fluoridated antiplaque dentifrice on the development of caries lesions adjacent to dental appliances bonded with ionomeric material is unknown.

METHODS

Fourteen orthodontic patients were randomly divided into 2 groups of 7. One group brushed 3 times a day with a fluoridated dentifrice, and the other used an experimental antiplaque fluoridated formulation. Bracket bases were randomly bonded with either resin-modified glass ionomer cement or composite resin to the buccal surfaces of either the maxillary left or right premolars in each subject. The teeth were banded, leaving a space on the buccal surface to allow dental plaque accumulation. After 28 days of dentifrice use, the teeth were extracted, and mineral loss in the enamel adjacent to the bonded material was assessed by cross-sectional microhardness.

RESULTS

Mineral loss in the enamel surrounding the bond with the resin-modified glass ionomer cement was lower (P <.05) than around the composite bond. Enamel demineralization was lower (P <.05) in subjects who used the experimental antiplaque fluoridated formulation than in those who used the fluoridated one.

CONCLUSIONS

The data suggest that an antiplaque fluoridated dentifrice is superior to one that is only fluoridated for reducing enamel demineralization adjacent to dental material bonded with composite, but the effect seems irrelevant when bonding is done with the ionomeric material.

Effect of the second-generation vascular disrupting agent OXi4503 on tumor vascularity

PURPOSE

As first-generation small-molecule vascular disrupting agents (VDA) have begun to enter clinical trials, second-generation agents are under active development. One such agent is the combretastatin A4 disodium phosphate (CA4P) analogue OXi4503 (CA1P).

EXPERIMENTAL DESIGN

C3H/HeJ mice bearing KHT sarcomas were treated with CA4P and OXi4503 and the effect on tumor vasculature was determined by evaluating the extent of vascular shutdown (Hoechst-33342 vessel staining) and tumor perfusion inhibition (dynamic contrast-enhanced magnetic resonance imaging). Dynamic contrast-enhanced magnetic resonance imaging and tumor necrosis end points also were used to examine the pathophysiologic tumor effects following repeated exposures to these agents.

RESULTS

Single doses of either agent (CA4P, 100 mg/kg; OXi4503, 25 mg/kg) resulted in an 80% to 90% reduction in tumor perfusion 4 hours after treatment. Whereas recovery in tumor perfusion was observed 48 hours posttreatment, this recovery was significantly slower in mice treated with OXi4503. Tumors re-treated with either VDA 72 hours after the first drug exposure showed a similar reduction and recovery in tumor perfusion. Histologic evidence showed the presence of a smaller viable rim after exposure to OXi4503 than that observed after CA4P treatment. Furthermore, the extent of recovery of tumor necrosis 72 hours after drug treatment was less for OXi4053.

CONCLUSIONS

The present studies show that the second-generation VDA OXi4503 possesses significant antivascular effects in solid tumors. Importantly, the vasculature of tumors of mice that had received an initial dose this agent was as responsive to a subsequent treatment.

Multi-micronutrient Sprinkles including a low dose of iron provided as microencapsulated ferrous fumarate improves haematologic indices in anaemic children: a randomized clinical trial

Home-fortification of complementary foods with micronutrients (including iron) as Sprinkles is a new strategy to control iron deficiency and anaemia in developing countries. However, the most effective dose and form of iron is not known. The purpose of this study was to compare the efficacy of various doses (12.5, 20 or 30 mg) and treatment methods (multi-micronutrient Sprinkles vs. ferrous sulphate drops) on haemoglobin (Hb) concentration after 8 weeks of treatment in anaemic children. In total, 133 anaemic Ghanaian children (Hb 70-99 g L(-1)) aged 6-18 months were randomly assigned to one of five daily interventions for 8 weeks. Out of the five interventions, four used Sprinkles, and one used iron drops. Of the four Sprinkles groups, three included 12.5, 20 or 30 mg of iron as ferrous fumarate, and one included 20 mg of iron as ferric pyrophosphate. The iron drops group included 12.5 mg of iron as liquid ferrous sulphate. Hb concentrations were measured at baseline, week 3 and week 8. The primary outcome measure was Hb concentration at 8 weeks after treatment. We compared differences in Hb and ferritin concentrations and prevalence of iron deficiency anaemia (Hb < 100 g L(-1) and soluble transferrin receptor concentrations >8.5 mg L(-1)) from baseline to 8 weeks within and between groups. Adherence and reporting of side effects (staining of the teeth, ease of use, diarrhoea and darkening of stools) were compared between groups. Mean change in Hb was 1.4 g L(-1) (SD = 1.8) (P = 0.0001). Change in Hb concentrations from baseline to 8 weeks was significant in all groups (P = 0.0001-0.0007), with no differences across groups. Geometric means of serum ferritin varied from 18.6 to 44.0 microg L(-1) at baseline. At week 8, these means were in the interval of 48.0-78.3 microg L(-1), with no group differences. Prevalence of iron deficiency anaemia decreased significantly from baseline to 8 weeks in all groups with the exception of the iron drops group, with no group differences. Adherence was lower in the drops group (64%) as compared with Sprinkles groups (84%). Greater staining of the teeth and less ease of use were reported in the drops group as compared with Sprinkles groups. A dose as low as 12.5 mg of iron as ferrous fumarate when provided as Sprinkles may be effective in anaemic children.

Salt dual-fortified with iodine and micronized ground ferric pyrophosphate affects iron status but not hemoglobin in children in Cote d'Ivoire

Deficiencies of iron and iodine are common in West Africa, and salt is one of very few food vehicles available for fortification. Salt dual-fortified with iodine and micronized ground ferric pyrophosphate (FePP) was tested for its efficacy in rural, tropical Côte d'Ivoire. First, salt and iron intakes, and iron bioavailability were estimated using 3-d weighed food records in 24 households. Local iodized salt was then fortified with 3 mg Fe/g salt as ground FePP (mean particle size = 2.5 mum), and stability, sensory and acceptability trials were done. The dual fortified salt (DFS) was distributed to households and its efficacy compared with that of iodized salt (IS) in a 6-mo, double-blind trial in 5- to 15-y-old iron-deficient children (n = 123). All children were dewormed at baseline. After 6 mo, serum ferritin (SF) and transferrin receptor (TfR) concentrations as well as body iron stores improved significantly in the DFS group but not in the IS GROUP (P < 0.05). Body iron increased from 4.6 +/- 2.7 to 5.9 +/- 2.7 mg/kg (mean +/- SD) in the DFS group; concentrations before and after treatment in the IS group were 5.5 +/- 2.9 and 5.6 +/- 3.1 mg/kg, respectively. The hemoglobin concentration and the prevalence of anemia did not change in either group. The prevalences of malaria, soil-transmitted helminths, and riboflavin deficiency were 55, 14, and 66%, respectively. In tropical West Africa, low-grade salt fortified with micronized ground FePP increased body iron stores but not hemoglobin in children. Iron utilization may have been impaired by the high prevalence of malaria and concurrent nutrient deficiencies.

Drug-induced expansion and differentiation of V gamma 9V delta 2 T cells in vivo: the role of exogenous IL-2

Human Vgamma9Vdelta2 T cells recognize nonpeptidic Ags generated by the 1-deoxy-d-xylulose 5-phosphate (many eubacteria, algae, plants, and Apicomplexa) and mevalonate (eukaryotes, archaebacteria, and certain eubacteria) pathways of isoprenoid synthesis. The potent Vgamma9Vdelta2 T cell reactivity 1) against certain cancer cells or 2) induced by infectious agents indicates that therapeutic augmentations of Vgamma9Vdelta2 T cell activities may be clinically beneficial. The functional characteristics of Vgamma9Vdelta2 T cells from Macaca fascicularis (cynomolgus monkey) are very similar to those from Homo sapiens. We have found that the i.v. administration of nitrogen-containing bisphosphonate or pyrophosphomonoester drugs into cynomolgus monkeys combined with s.c. low-dose (6 x 10(5) U/animal) IL-2 induces a large pool of CD27+ and CD27- effector/memory T cells in the peripheral blood of treated animals. The administration of these drugs in the absence of IL-2 is substantially less effective, indicating the importance of additional exogenous costimuli. Shortly after the costimulatory IL-2 treatment, only gammadelta (but not alphabeta) T cells expressed the CD69 activation marker, indicating that Vgamma9Vdelta2 T lymphocytes are more responsive to low-dose IL-2 than alphabeta T cells. Up to 100-fold increases in the numbers of peripheral blood Vgamma9Vdelta2 T cells were observed in animals receiving the gammadelta stimulatory drug plus IL-2. Moreover, the expanded Vgamma9Vdelta2 T cells were potent Th1 effectors capable of releasing large amounts of IFN-gamma. These results may be relevant for designing novel (or modifying current) immunotherapeutic trials with nitrogen-containing bisphosphonate or pyrophosphomonoester drugs.

Effects of Emulsifying Salts on the Turbidity and Calcium-Phosphate–Protein Interactions in Casein Micelles

Influence of emulsifying salts (ES) on some physical properties of casein micelles was investigated. A reconstituted milk protein concentrate (MPC) solution (5% wt/wt) was used as the protein source and the effects of ES [0 to 2.0% (wt/wt)] were estimated by measuring turbidity, acid-base titration curves and amount of casein-bound Ca and inorganic P (P(i)). Various ES, trisodium citrate (TSC), or sodium phosphates (ortho-, pyro-, or hexameta-) were added to MPC solution, and all samples were adjusted to pH 5.8. Acid-base buffering curves were used to observe changes in the amount and type of insoluble Ca phosphates. An increase in the concentration of TSC added to MPC solution decreased turbidity, buffering at pH approximately 5 (contributed by colloidal Ca phosphate), and amount of casein-bound Ca and P(i). Addition of up to 0.7% disodium orthophosphate (DSP) did not significantly influence turbidity, buffering curves, or amount of casein-bound Ca and P(i). When higher concentrations (i.e., > or =1.0%) of DSP were added, there was a slow decrease in turbidity. With increasing concentration of added tetrasodium pyrophosphate (TSPP), turbidity and buffering at pH approximately 5 decreased, and amount of casein-bound Ca and P(i) increased. When small concentrations (i.e., 0.1%) of sodium hexameta-phosphate were added, effects were similar to those when TSPP were added but when higher concentrations (i.e., > or =0.5%) were added, the buffering peak shifted to a higher pH value, and amount of casein-bound Ca and P(i) decreased. These results suggested that each type of ES influenced casein micelles by different mechanisms.

Iron Absorption and Bioavailability in Rats of Micronized Dispersible Ferric Pyrophosphate

Unlike commercial ferric pyrophosphate, micronized dispersible ferric pyrophosphate (MDFP: SunActive FeTM) does not precipitate and is completely dispersible in liquid form. MDFP shows a sharp particle size distribution at a nanometer level, which is several times smaller than that of commercial ferric pyrophosphate. The bioavailability of MDFP was compared to ferric pyrophosphate, sodium ferrous citrate, and ferrous sulfate by three bioavailability tests in rats; namely the serum iron concentration curve, the hemoglobin regeneration efficiency, and Association of Official Analytical Chemists' hemoglobin repletion test. The high area under curve value, a lag in peak time, and continued high serum iron concentration by MDFP over the other iron compounds indicates a sustained release of iron in the serum iron concentration curve method. MDFP showed the highest hemoglobin regeneration efficiency among all the iron compounds tested. The relative biological value of MDFP per unit of ferrous sulfate in each bioavailability test showed a high value as compared to other iron compounds. The above results suggest that MDFP is an ideal compound with high bioavailability for iron fortification in various liquid applications.

Efficient Production of Cloned Bovine Embryos Using cdc2 kinase Inhibitor

This study was carried out to compare the effects of the combination of ionomycin with a H1-histone kinase inhibitor (dimethylaminopurine, DMAP) or cdc2 kinase inhibitor (sodium pyrophosphate, SPP) on the development of reconstituted bovine eggs. For this study, the enucleated bovine oocytes were injected with a presumptive primordial germ cell pre-treated with 1% sodium citrate, and randomly allocated into three activation groups: Group 1 (ionomycin 5 microm, 5 min), Group 2 (ionomycin + DMAP 1.9 mm, 3 h), and Group 3 (ionomycin + SPP 2 mm, 3 h). The reconstituted eggs were compared on the rates of cleavage and development with the blastocyst stage and the ploidy of embryos at 96 h post-activation. Cleavage rates and blastocyst development in Groups 1, 2 and 3 were 7 and 0%, 63 and 17%, and 53 and 14%, respectively. The chromosomal composition differed significantly (p < 0.05) among treatments. Although the embryos in Group 1 had significantly lower developments, 60% of embryos evaluated had diploid chromosomal sets. In contrast, approximately 60% of embryos in Group 2 had abnormal ploidy (21% polyploid and 38% mixoploid). In Group 3, the appearance of abnormal chromosome sets was reduced with the proportion of diploid embryos being increased to 86% (19 of 22), significantly higher (p < 0.05) than in Group 2. It can be concluded that the use of SPP with ionomycin reduces greatly the incidence of chromosomal abnormalities, and may be applicable for the activation of nuclear transplant bovine embryos.

Effects of malathion plus superphosphate or urea on Najdi sheep

The effects of p.o. administration of the combination of malathion + superphosphate or urea on Najdi sheep were evaluated in sheep dosed as untreated controls, malathion-treated at 25 mg/kg/d, superphosphate-treated at 450 mg/kg/d, urea-treated at 450 mg/kg/d, malathion-treated at 25 mg/kg/d + superphosphate treated at 450 mg/kg/d, or malathion treated at 25 mg/kg/d + urea treated at 450 mg/kg/d. Oral doses of malathion alone were lethal after 6 d, and malathion + urea were fatal after 6-8 d. Malathion + superphosphate caused death after 2-3 d. Malathion, but not superphosphate or urea, inhibited serum cholinesterase activity. Hepatonephropathy correlated with changes in serum AST, ALP, cholesterol, triglyceride, bilirubin, urea, total protein and albumin. Neither malathion nor its combination with superphosphate or urea caused peripheral neuropathy.

Iron bioavailability in infants from an infant cereal fortified with ferric pyrophosphate or ferrous fumarate

BACKGROUND

Infant cereals are commonly fortified with insoluble iron compounds with low relative bioavailability, such as ferric pyrophosphate, because of organoleptic changes that occur after addition of water-soluble iron sources.

OBJECTIVE

Our objective was to compare iron bioavailability from ferric pyrophosphate with an alternative iron source that is soluble in dilute acid, ferrous fumarate, and to evaluate the influence of ascorbic acid on iron bioavailability from ferrous fumarate in infants.

DESIGN

Iron bioavailability was measured as the incorporation of stable iron isotopes into erythrocytes 14 d after administration of labeled test meals (25 g dry wheat and soy infant cereal, 100 g water, and 2.5 mg Fe as [57Fe]ferric pyrophosphate or [57Fe]ferrous fumarate). Ascorbic acid was added to all test meals (25 mg in study 1 or 25 or 50 mg in study 2). Infants were fed each test meal on 4 consecutive days under standardized conditions. The 2 different test meals within each study were administered 2 wk apart in a crossover design.

RESULTS

Geometric mean iron bioavailability was significantly higher from [57Fe]ferrous fumarate than from [57Fe]ferric pyrophosphate [4.1% (range: 1.7-14.7%) compared with 1.3% (range: 0. 7-2.7%); n = 8, P = 0.008]. In this study, doubling the ascorbic acid content did not further enhance iron bioavailability; the geometric means (range) were 3.4% (1.9-6.6%) and 4.2% (1.2-18.7%) for the test meals with 25 and 50 mg ascorbic acid added, respectively (n = 9).

CONCLUSION

Iron bioavailability from iron-fortified infant cereals can be improved by using an iron compound with high relative bioavailability and by ensuring adequate ascorbic acid content of the product.

Dialysate iron therapy: infusion of soluble ferric pyrophosphate via the dialysate during hemodialysis

BACKGROUND

Soluble iron salts are toxic for parenteral administration because free iron catalyzes free radical generation. Pyrophosphate strongly complexes iron and enhances iron transport between transferrin, ferritin, and tissues. Hemodialysis patients need iron to replenish ongoing losses. We evaluated the short-term safety and efficacy of infusing soluble ferric pyrophosphate by dialysate.

METHODS

Maintenance hemodialysis patients receiving erythropoietin were stabilized on regular doses of intravenous (i.v.) iron dextran after oral iron supplements were discontinued. During the treatment phase, 10 patients received ferric pyrophosphate via hemodialysis as monthly dialysate iron concentrations were progressively increased from 2, 4, 8, to 12 micrograms/dl and were then sustained for two additional months at 12 micrograms/dl (dialysate iron group); 11 control patients were continued on i.v. iron dextran (i.v. iron group).

RESULTS

Hemoglobin, serum iron parameters, and the erythropoietin dose did not change significantly from month 0 to month 6, both within and between the two groups. The weekly dose of i.v. iron (mean +/- SD) needed to maintain iron balance during month 6 was 56 +/- 37 mg in the i.v. iron group compared with 10 +/- 23 mg in the dialysate iron group (P = 0.001). Intravenous iron was required by all 11 patients in the i.v. iron group compared with only 2 of the 10 patients receiving 12 micrograms/dl dialysate iron. The incidence of adverse effects was similar in both groups.

CONCLUSIONS

Slow infusion of soluble iron pyrophosphate by hemodialysis may be a safe and effective alternative to the i.v. administration of colloidal iron dextran in maintenance hemodialysis patients.

Development and validation of a short-term clinical model for assessing calculus inhibitory agents

The purpose of this project was to develop and validate an efficient, short-term clinical model for assessing topically-applied anticalculus agents. In this model, calculus development occurred within 14 days on both labial and lingual surfaces of the mandibular anterior teeth. Because of documented long-term clinical efficacy, pyrophosphate dentifrices were used to investigate the validity of the short-term calculus model for evaluating anticalculus agents. This paper provides the results of the final 3 studies conducted during the development of this model. For each study, the design consisted of two 14-day phases, i.e., a control phase and a treatment phase, separated by a 7-day washout phase. At the start of each phase, a prophylaxis was performed on the mandibular anterior teeth to remove all plaque and calculus. At the end of each phase, supragingival calculus formation on the labial and lingual surfaces of these same teeth was measured using the VMI scoring method. Twice a day during the control phase, subjects applied a control dentifrice undiluted to the test teeth with a custom-fitted toothshield and brushed only the exposed teeth with the same dentifrice. For the treatment phase, subjects were randomly assigned to groups balanced on the basis of control-phase calculus scores and then delivered the dentifrices using the toothshield as in the first phase. After 14 days, calculus formation occurred in all groups. However, the pyrophosphate dentifrice groups had significantly less calculus (16-30%) than the control dentifrice group. These studies demonstrated that this methodology permitted rapid formation of dental calculus, and by substantiating with anticalculus systems documented to have activity in long-term human trials, it is concluded that this short-term clinical model is valid for assessing anticalculus agents.

The effects of pharmaceutical excipients on small intestinal transit

1. The effect of three iso-osmotic pharmaceutical excipient solutions on gastrointestinal transit were investigated in eight healthy male volunteers. Each subject received 200 ml radiolabelled purified water, or a 200 ml solution of sodium acid pyrophosphate ((SAPP) 1.1 g/200 ml), mannitol (2.264 g/200 ml) or sucrose (4.08 g/200 ml) in a four way cross over design. On each of the study days the volunteers also received five 6 mm diameter non-disintegrating tablets. Dual isotope gamma scintigraphy was used to assess the transit behaviour of the tablets and solutions. 2. There were no significant differences between the gastric emptying times of the four solution formulations. Rapid gastric emptying was observed in all cases (mean t 50% varied from 11-14 min). 3. Small intestinal transit (SIT) times for the SAPP and mannitol solutions were reduced by 39 and 34%, respectively, when compared with the control solution (purified water = 240 min; SAPP = 147 min; mannitol = 158 min). The 95% confidence limits for the mean differences in SIT time between the control and SAPP solutions was 39-94-149 min, and 40-82-124 min between the mannitol and the control. Intestinal transit for the sucrose solution was similar to that for the control solution (sucrose = 229 min). 4. There were no significant differences in the transit times of the non-disintegrating tablet preparations, when co-administered with each solution.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of three commercially available dentifrices containing triclosan on supragingival plaque formation and gingivitis: a six month clinical study

In order to compare the antiplaque and antigingivitis activity of three commercially-available triclosan containing dentifrices with that of a placebo dentifrice without triclosan, a double-blind clinical study was conducted on 194 subjects over six months. Following baseline supragingival plaque and gingivitis examinations and a complete oral prophylaxis, subjects were stratified by their whole mouth baseline plaque (modified Quigley-Hein) and gingivitis (modified Löe-Silness) scores and then randomly assigned to one of four dentifrice using groups. Plaque and gingivitis examinations were then performed after six weeks, three months and six months use of the dentifrices. Subjects brushed twice daily in their customary manner. The triclosan/soluble pyrophosphate and the triclosan/zinc citrate commercially available dentifrices did not provide statistically significant reductions in either supragingival plaque accumulation or gingivitis at any of the examination intervals, as compared to the placebo dentifrice. The subjects using the commercially available triclosan/copolymer dentifrice had, after six months, statistically significant reductions in supragingival plaque (11.3 per cent), plaque severity (18.8 per cent), gingivitis (19.9 per cent) and gingivitis severity (27.8 per cent), as compared to the placebo dentifrice.

Growth-inhibitory effect of pyrophosphate on oral bacteria

The purpose of this investigation was to determine whether pyrophosphate, the anticalculus component of tartar-control dentifrices, exerts antimicrobial activity against oral bacteria commonly found in supragingival plaque. Minimal inhibitory concentrations of pyrophosphate were determined for Streptococcus sanguis, Streptococcus mutans (serotype c), Actinomyces viscosus and Actinomyces naeslundii. All of the bacteria tested were susceptible to pyrophosphate with identical minimal inhibitory concentrations of 0.67% wt/vol (25 mM). Bactericidal kinetics assays revealed that both S. mutans and A. viscosus were killed by pyrophosphate, with the latter being considerably more susceptible. The mechanism of killing was not due to high ionic strength, as comparable controls showed no loss in numbers of viable cells. Brief exposure (two 5-min incubations) of S. mutans to pyrophosphate and sodium dodecyl sulfate caused pronounced inhibition of growth over the 24-h test period. Under the constraints of the conditions used, these studies indicate that pyrophosphate and sodium dodecyl sulfate can substantially inhibit the growth of oral bacteria. These compounds may affect the oral microflora of patients who routinely use tartar-control dentifrices and mouthrinses.

The effects of three silica dentifrices containing Triclosan on supragingival plaque and calculus formation and on gingivitis

A double blind, seven month clinical study was conducted to determine the effects of three Triclosan containing test dentifrices on supragingival plaque, gingivitis and supragingival calculus formation compared to a 0.8 per cent monofluorophosphate-silica control dentifrice. Each test dentifrice contained 0.3 per cent Triclosan; additionally one contained 0.75 per cent zinc citrate, the second contained 2 per cent Gantrez and the third contained 5 per cent pyrophosphate. Subjects were assigned to one of the three test groups or to the control group according to random allocation within nine strata. Subjects were evaluated for supragingival plaque and calculus formation and for gingivitis after one, four and seven months' use of the dentifrices. After seven months, the Triclosan/Gantrez and the Triclosan/pyrophosphate dentifrices each provided a statistically significant reduction of approximately 25 per cent in gingival bleeding compared to the control. Neither dentifrice gave statistically significant reductions in supragingival plaque or calculus formation. In contrast, the Triclosan/zinc citrate dentifrice provided statistically significant reductions of 33 per cent in supragingival plaque, 51 per cent in gingival bleeding and 67 per cent in supragingival calculus formation. The reductions in gingival bleeding and calculus formation were statistically superior to those of the Triclosan/Gantrez and the Triclosan/pyrophosphate products. The results demonstrate that use of the Triclosan/zinc citrate dentifrice over a seven month period provided statistically significant and clinically relevant reductions in supragingival plaque and calculus formation, and control of gingivitis as compared to a control dentifrice.

Evaluation of anti-calculus efficacy. An SEM method of evaluating the effectiveness of pyrophosphate dentifrice on calculus formation

A double-blind, cross-over study was carried out to assess the anti-calculus effectiveness of a pyrophosphate containing cleaning gel. 2 groups of 30 heavy calculus formers were followed up comparing conventional clinical scoring systems (Volpe-Manhold-Index and Marginal-Line-Calculus-Index) and micromorphologic SEM criteria of calculus formation and inhibition. The results indicated that after a 3-month period, there was a significant reduction of calculus formation compared to a placebo gel. The proposed SEM calculus index (SEMCI) objectively reflects the reduction of supragingival calculus formation.

Synergistic effect of pyrophosphate and sodium dodecyl sulfate on periodontal pathogens

Our previous studies have shown that pyrophosphate (PPi), the anticalculus component of tartar-control dentifrices, inhibits the growth of organisms associated with coronal and root surface caries. The purposes of this investigation were to: 1) determine if periodontal pathogens are similarly susceptible to the growth-inhibitory properties of PPi; and 2) determine if combinations of pyrophosphate-sodium dodecyl sulfate (PPi-SDS) inhibit growth synergistically. Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Eikenella corrodens, and Campylobacter rectus (formerly Wolinella recta) were cultured in appropriate enriched media under anaerobic conditions. Inhibition assays were performed in tubes containing media supplemented with PPi and/or SDS. A range of concentrations of PPi and SDS in 2-fold increments was employed, with each concentration assayed in triplicate. Minimal inhibitory concentration (MIC) analyses revealed all of the bacteria were susceptible to PPi and SDS, with MICs of 0.67% (25 mM) and 0.01% w/v respectively. Combination studies with PPi-SDS showed much greater growth inhibition against P. gingivalis and A. actinomycetemcomitans than achieved with the agents individually. Determination of fractional inhibitory concentration indices indicated a synergistic growth-inhibitory effect. Under the constraints of the conditions employed, these studies demonstrate the efficacy of PPi-SDS combinations in inhibiting the growth of periodontal pathogens. It is conceivable that these compounds may have clinical benefit as a subgingival irrigant.

General principles for the delivery of active agents from mouthrinses

Mouthrinses are a convenient and accepted method of delivering oral therapeutic agents. Efficacy, however, depends on several factors including the type of drug used and its properties, use of an optimal delivery vehicle, patient compliance or usage practices and the therapeutic indication for which they are used. Three classes of therapeutic agents currently used in mouthrinses are reviewed, including fluorides, tartar control agents and antimicrobial compounds. The specific agents in these categories, some of which are currently used in mouthrinses, span a broad range of chemical and pharmacological properties. A basic understanding of these properties allows for a rational use of these agents in therapeutically optimised formulations.

Rinses for the control of supragingival calculus formation

Recent epidemiologic studies have confirmed the widespread presence of calculus in teenagers and adults of all ages. Among the multiple anticalculus strategies that have been proposed over the years inhibition of crystal growth has been the most attractive. Current formulations in antitartar toothpastes utilise either zinc salts or various pyrophosphate combinations. In mouthrinses three recent clinical studies have established the superiority of a formulation that contains 1 per cent soluble pyrophosphate, 0.45 per cent of the copolymer of methoxyethelene and maleic acid (Gantrez) and 0.02 per cent sodium fluoride. Three and six month studies demonstrated reductions in calculus scores of 31.7-37.7 per cent using the Volpe-Manhold scoring method. A comparative study of 1 per cent pyrophosphate rinses with and without the copolymer (Gantrez) affirmed its importance to the efficacy of the formulation (31.7 per cent vs 14.4 per cent).

Ferrous fumarate fortification of a chocolate drink powder

An evaluation was made into the usefulness of ferrous fumarate as an iron fortificant for an experimental chocolate drink powder targetted to children and adolescents. Organoleptically ferrous furmarate was acceptable when the chocolate drink powder was reconstituted in milk or water that was heated to less than 80 degrees. Unacceptable colour changes occurred, however, when boiling milk or water were used. In human Fe absorption studies when the Fe compounds were added to the chocolate drink immediately before consumption, ferrous fumarate was 3.31% absorbed compared with 2.82% for ferrous sulphate and 2.11% for ferric pyrophosphate. When the Fe compounds were processed during the manufacture of the chocolate drink powder, the absorption of ferrous furmarate was 5.27%, ferrous sulphate 2.62% and ferric pyrophosphate 0.55%. Ascorbic acid had little or no effect on the absorption of ferrous furmarate. It is concluded that food processing can influence the relative absorption of fortification Fe and that, if not reconstituted with boiling milk or water, ferrous fumarate could be a useful compound for the fortification of chocolate drink powders.

Intraperitoneal phosphate administration in hungry bone syndrome

Hypophosphatemia complicating parathyroidectomy for secondary hyperparathyroidism in renal failure is usually corrected by the oral or intravenous routes. We present a case in which those methods of treatment were not possible, and the phosphate was administered intraperitoneally. Phosphate was added as one molar sodium diphosphate solution to the dialysis fluid. In our case the procedure was well tolerated, phosphate blood levels were rapidly corrected, no alterations in calcium, magnesium or other parameters were detected and the patient was discharged in good condition. In selected cases of hungry bone syndrome after parathyroidectomy, intraperitoneal phosphate can be used safely.

The effects of 1% pyrophosphate and 0.02% sodium fluoride on artificial caries lesions in vivo

We evaluated the potential of a pyrophosphate-fluoride solution to affect the remineralizing-demineralizing equilibrium, i.e., caries-inhibiting/-promoting effects on enamel in vivo. Fifteen subjects carried dentin blocks and enamel thin sections with artificial caries lesions in removable partial dentures for periods of two weeks, during which time they rinsed twice daily in a double-blind, randomized cross-over design with solutions containing (a) 90 ppm F, (b) 90 ppm F and 1% pyrophosphate, or (c) no active agents (placebo). A severe cariogenic challenge provided to the lesions by plaque under a stainless steel mesh cover resulted in the placebo-treated lesions losing 70.2% +/- 72.1% mineral. The pyrophosphate rinse with fluoride held the mineral loss to only 28.1 +/- 52.8%, while the fluoride rinse without pyrophosphate held the loss to 24.2 +/- 50.1%. The differences between the fluoride and placebo results were significant (p less than 0.01), but the difference between the two fluoride groups was not. A large amount of fluoride was deposited in the dentin lesions. In the surface layer, the concentration was increased from 1000 ppm F to more than 2300 ppm F by both fluoride treatments. The concentration of fluoride in both groups of fluoride-treated lesions further increased to more than 3500 ppm F in the approximate center of the lesion before declining in deeper layers toward the level found in the placebo-treated group. The findings from both mineral change and fluoride uptake phases of this study show that in the presence of 90 ppm F, 1% pyrophosphate did not promote demineralization of artificial caries lesions.

Comparison of technetium-99m pyrophosphate and technetium-99m DTPA aerosols for SPECT ventilation lung imaging

Although [99mTc] diethylenetriaminepentaacetic acid (DTPA) is currently the most widely used radioaerosol, rapid alveolar clearance limits its usefulness for single photon emission computed tomography (SPECT) ventilation lung imaging. Previous research has shown that [99mTc]phosphate compounds have high alveolar deposition and slow clearance and thus provide suitable aerosols for pulmonary ventilation studies. We have compared the pulmonary retention and blood levels of [99mTc]pyrophosphate (PYP) and [99mTc]DTPA in eight normal nonsmoking male volunteers. These two radioaerosols have comparable pulmonary deposition. Technetium-99m PYP, however, has a much slower pulmonary clearance which allows sufficient time (20 or more minutes) for SPECT data acquisition using a single-headed rotating gamma camera. While the radiation absorbed dose to the lungs for [99mTc]PYP (0.31 rad/mCi) is greater than for [99mTc]DTPA (0.11 rad/mCi), it is at a clinically acceptable and safe level.

IV radionuclide total-body arteriography: a new noninvasive whole-body screening procedure--a case report

Recently the authors introduced a new technique of intravenous (IV) radionuclide total-body arteriography. The major arterial system, multiple organs of the whole body, and cardiac function can be evaluated with one small IV injection in the arm. After analyzing more than 1000 cases, they have found that many pathologies can be detected and/or confirmed in this procedure. This new technique may be used as a general whole-body screening test for those patients at high risk for disease.

Anti-herpes virus combinations in relation to drug resistance

Two broad categories of combinations have been subject to experimental investigation against HSV-1 and HSV-2; those consisting of an active antiviral drug and an inhibitor of its catabolism and those which contain two active antiviral agents. The latter seek to exploit biochemical mechanisms likely to lead to a synergistic or complementary interaction. Examples of both types of combination for the suppression of resistance development and for the treatment of infection caused by resistant strains are discussed. Their possible relevance to the latent state is considered.

The effect of a fluoride dentifrice containing an anticalculus agent on dental caries in children

In this double-blind caries study, 1160 Taiwanese children (ages 8-15) completed a program using a test dentifrice containing 1.243 percent sodium fluoride and soluble pyrophosphates, or a control dentifrice without these agents. The average reduction of new carious tooth surfaces was 39 percent with the sodium fluoride dentifrice.

Determining the effective emetic dosage of tetrapotassium pyrophosphate (TKPP) in dogs

The effect of TKPP on emesis was examined in adult "conditioned random source" mongrel dogs. Only dogs that exhibited emesis with CuSO4, were used. The effect of dosage and concentration of TKPP on emesis was highly significant. The effective combinations of dose and concentration were 4,800, 2,400, or 1,200 mg/head at 5, 10, or 20%. In all the tested dogs, 4,800 mg of 20% TKPP was effective inducing emesis. The mean latency of emesis in dogs was 7 min, 33 sec (95% confidence limits: 5 min, 58 sec 9 min, 7 sec).

Purification and some properties of rat liver tyrosyl-tRNA synthetase

Rat liver cytoplasmic tyrosine:tRNA ligase (tyrosine:tRNA ligase, EC 6.1.1.1) was purified by ultracentrifugation, DEAE-cellulose chromatography and repeated phosphocellulose chromatography by more than 1500-fold. The molecular weight of the enzyme was approx. 150 000 as determined by Sephadex G-200 gel filtration. On the basis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the enzyme consisted of two subunits, each of 68 000 daltons. We found the following Km values for the enzyme: 13 micrometer for tyrosine and 1.7 mM for ATP in the ATP:PPi exchange reaction and 13 micrometer for tyrosine, 210 micrometer for ATP and 0.14 micrometer for tRNATyr in the aminoacylation reaction. The rate of tyrosyl-tRNA synthesis was 50-fold lower than that of ATP:PPi exchange. Addition of a saturating amount of tRNA did not affect the rate of ATP:PPi exchange.

Scintigraphic evaluation of suspected acute myocardial infarction

Ninety-one patients with chest pain suggestive of acute myocardial infarction were studied by static technetium Tc 99m stannous pyrophosphate scintigraphy and dynamic sodium pertechnetate Tc 99m cardioangiography. Twenty-three of 26 patients (88%) with acute transmural infarcts and 12 of 17 patients (71%) with nontransmural infarcts had abnormal static studies. In 45 patients with negative scintigrams, ECG or serum enzyme changes consistent with acute infarction failed to develop. Three false-positive static studies (6%) were recorded. Twenty of 43 (47%) patients with acute infarction had hemodynamic or structural abnormalities identified by cardioangiography. The dynamic study also proved helpful in localizing the site of infarction and in ruling out certain causes of false-positive static scintigrams.

The influence of orthophosphate on the renal handling of inorganic pyrophosphate in man and dog

1. The urinary excretion of inorganic pyrophosphate (PPi), a known inhibitor of the growth and aggregation of crystals of calcium phosphate and calcium oxalate, increases after ingestion of orthophosphate (Pi). This effect may contribute to the apparent ability of oral phosphate to reduce the formation of urinary stones in man. This paper is a study of the mechanism by which Pi increases PPi excretion, investigated by renal clearance techniques in man and renal arterial infusion in dogs. PPi in plasma was measured by an isotope-dilution method after ion-exchange chromatography. 2. The mean renal clearance of endogenous PPi in ten men was 7-9 +/- 1-7 (SE) ml/min, and the mean ratio of PPi clearance to creatinine clearance was 0-08 +/- 0-02 (SE). The oral ingestion of Pi increased the urinary excretion and renal clearance of PPi about threefold, without significantly changing its concentration in plasma. 3. In dogs, the infusion of Pi into one renal artery caused a greater increase in urinary PPi from the infused than from the non-infused kidney, an effect that could be accentuated by simultaneous intravenous infusion of PPi. In dogs, only 1-3% of an injected or infused dose of PPi appeared intact in the urine, regardless of whether it was infused into the systemic or renal circulation. 4. These results suggest that Pi has a direct affect on the kidney to increase the excretion of PPi. It is possible that Pi either interferes with tubular reabsorption of PPi, perhaps by competing for a common tubular transport mechanism, or that Pi diminishes the intrarenal hydrolysis of PPi.