Fracturas atípicas de fémur asociadas al uso de bifosfonatos / Bisphosphonate associated atypical femur fractures

Resumen Los bifosfonatos son medicamentos ampliamente conocidos por su efecto antagonista de la resorción ósea y la consecuente reducción del riesgo de fracturas en los pacientes con osteoporosis. La literatura actual provee evidencia en términos de datos clínicos y experimentales que asocian el uso prolongado de estos medicamentos con un aumento en el riesgo de fracturas atípicas de fémur. Para establecer si esta asociación es clínicamente relevante, se requiere realizar estudios posteriores que incluyan la relación entre otros factores que podrían influir en la aparición de este tipo de fracturas como lo es la propia enfermedad osteoporótica, el tipo de bifosfonato utilizado, el mecanismo lesional que originó la fractura, medicamentos concomitantes y patologías asociadas.

Abstract Bisphosphonates are medications that are widely known for their antagonizing effect on bone resorption and their consequent reduction in the risk of fractures in patients with osteoporosis. Current literature provides evidence in terms of experimental and clinical data associating prolonged use of these drugs with an increase in the risk of atypical femur fractures. To establish if this association is clinically relevant, there lies a need for further studies that take into account other factors that might influence the occurrence of these type of fractures, like the osteoporotic disease itself, age, intake of other drugs and associated systemic illnesses.

Treatment of iron deficiency anemia with liposomal iron in inflammatory bowel disease: efficacy and impact on quality of life.

Background Anemia is a clinical condition frequently seen in patients with inflammatory bowel disease, which is responsible for a significant loss of quality of life. Objective To assess the efficacy and safety of using oral liposomal iron to treat iron deficiency anemia in inflammatory bowel disease patients, as well as assess the impact of this treatment on psychometric scores. Methods Patients with inactive/mildly active inflammatory bowel disease were screened for anemia in this interventional pilot study conducted from November 2016 to March 2018. Patients with mild anemia were treated with oral liposomal iron for 8 weeks. Main outcome measure The primary endpoint of the study was the response to liposomal oral iron therapy. Treatment response was defined as patients who achieved a hemoglobin increase of ≥ 1 g/dL and/or hemoglobin normalization by the 8th week of treatment. Results Out of 200 screened patients, 40 (20%) had anemia. Of the 21 patients who completed treatment, 13 (62%) responded to oral liposomal iron replacement therapy (mean increases of hemoglobin from 11.4 to 12.6 g/dL). The transferrin saturation index increased by an average of 10.2 (p = 0.006) and the quality of life by 26.3 (p < 0.0001). There was also a mean reduction of 9.2 in the perception of fatigue (p < 0.0001). Conclusion Treatment with oral liposomal iron is effective in improving mild iron deficiency anemia and quality of life, as well as in decreasing fatigue in patients with inactive or mildly active inflammatory bowel disease.

Pharmacokinetics of ferric pyrophosphate citrate administered via dialysate and intravenously to pediatric patients on chronic hemodialysis.

BACKGROUND: Iron deficiency is a common cause of anemia in pediatric patients with hemodialysis-dependent chronic kidney disease (CKD-5HD). Ferric pyrophosphate citrate (FPC, Triferic®) donates iron directly to transferrin, bypassing the reticuloendothelial system and avoiding iron sequestration. Administration of FPC via dialysate or intravenously (IV) may provide a suitable therapeutic option to current IV iron preparations for these patients. METHODS: The pharmacokinetics and safety of FPC administered via dialysate and IV to patients aged < 6 years (n = 3), 6 to < 12 years (n = 4), and 12 to <18 years (n = 15) were investigated in a multicenter, open-label, two-period, single-dose study. FPC (0.07 mg iron/kg) was infused IV into the venous blood return line during hemodialysis session no. 1. FPC iron was added to bicarbonate concentrate to deliver 2 µM (110 µg/L) iron via dialysate during hemodialysis session no. 2. RESULTS: Mean serum total iron concentrations peaked 3 to 4 h after administration via dialysate and 2 to 4 h after IV administration and returned to baseline by 10 h after the start of hemodialysis for both routes. Iron exposure was greater after administration via dialysate than after IV administration. The absolute amount of absorbed iron after administration via dialysate roughly doubled with increasing age, but the weight-normalized amount of absorbed iron was relatively constant across age groups (~ 0.06-0.10 mg/kg). FPC was well tolerated in the small number of patients studied. CONCLUSIONS: FPC iron can be administered to pediatric patients with CKD-5HD via dialysate or by the IV route. Further study of FPC administered to maintain hemoglobin concentration is indicated.

Vascular disruptive agent OXi4503 and anti-angiogenic agent Sunitinib combination treatment prolong survival of mice with CRC liver metastasis.

BACKGROUND: Preclinical research indicate that vascular disrupting agent (VDA) treatment induces extensive tumor death but also a systemic mobilization of bone marrow derived cells including endothelial progenitor cells (EPC) leading to revascularization and renewed growth within the residual tumor. This study investigates if combination of VDA with the anti-angiogenic agent Sunitinib increases the treatment efficacy in a colorectal liver metastases mouse model. METHODS: CBA mice with established liver metastases were given a single dose of OXi4503 at day 16 post tumor induction, a daily dose of Sunitinib starting at day 14 or day 16 post tumor induction or a combination of Sunitinib given daily from day 14 or day 16 post tumor induction in combination with a single dose of OXi4503 at day 16. Treatment was terminated at day 21 post tumor induction and its effects were assessed using stereological and immunohistochemical techniques. Long term effects were assessed in a survival study. RESULTS: Combination with long (7 day) Sunitinib treatment lead to liver toxicity but this was ameliorated in the shorter (5 day) treatment without significantly altering the effects on tumor reduction. Combination treatment resulted in significant reduction of viable tumor, reduction in tumor vasculature, reduction in tumor proliferation, increase in tumor apoptosis and prolonged mouse survival compared to control and single arm treatments. Complete tumor eradication was not achieved. Redistribution of E-cadherin and strong up regulation of ZEB1 and Vimentin were observed in the surviving tumor; indicative of epithelial to mesenchymal transition (EMT), a mechanism that could contribute to tumor resistance. CONCLUSIONS: Combination treatment significantly reduces viable tumor and prolongs animal survival. EMT in the surviving tumor may prevent total tumor eradication and could provide novel targets for a more lasting treatment.

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.

[Acute kidney failure and renal replacement therapy after colonoscopy in a 63-year-old woman]. / Akutes Nierenversagen mit Dialysepflichtigkeit nach Koloskopie bei einer 63-jährigen Patientin.

A 63-year-old woman presented with intestinal disorder, alternating between obstipation and diarrhoea. Sodium phosphate/diphosphate (Fleet®) was used in preparation for colonoscopy. Within 24 h the patient developed severe hyperphosphatemia and oliguric acute kidney failure with the need of renal replacement therapy. This case illustrates the rare event of phosphate nephropathy after colonoscopy.

[Tolerability of iron preparation Actiferol Fe® in children treated for iron deficiency anemia]. / Ocena tolerowania preparatu zelaza actiferol fe® u dziecl z niedokrwistoscia z niedoboru zelaza.

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.

Ferric pyrophosphate citrate administered via dialysate reduces erythropoiesis-stimulating agent use and maintains hemoglobin in hemodialysis patients.

Ferric pyrophosphate citrate (FPC) is a water-soluble iron salt administered via dialysate to supply iron directly to transferrin. The PRIME study tested whether treatment with FPC could reduce prescribed erythropoiesis-stimulating agent (ESA) use and maintain hemoglobin in hemodialysis patients. This 9-month, randomized, placebo-controlled, double-blind, multicenter clinical study included 103 patients undergoing hemodialysis 3-4 times weekly. The FPC group received dialysate containing 2 µmol/l of iron. The placebo group received standard dialysate. A blinded central anemia management group facilitated ESA dose adjustments. Intravenous iron was administered according to the approved indication when ferritin levels fell below 200 µg/l. The primary end point was the percentage change from baseline in prescribed ESA dose at end of treatment. Secondary end points included intravenous iron use and safety. At the end of treatment, there was a significant 35% reduction in prescribed ESA dose in FPC-treated patients compared with placebo. The FPC patients used 51% less intravenous iron than placebo. Adverse and serious adverse events were similar in both groups. Thus, FPC delivered via dialysate significantly reduces the prescribed ESA dose and the amount of intravenous iron needed to maintain hemoglobin in chronic hemodialysis patients.

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.

Oligoartritis por pirofosfato con sobreinfección por Streptococcus pneumoniae: a propósito de un caso / No disponible

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Low-dose metronomic cyclophosphamide combined with vascular disrupting therapy induces potent antitumor activity in preclinical human tumor xenograft models.

Vascular disrupting agents preferentially target the established but abnormal tumor vasculature, resulting in extensive intratumoral hypoxia and cell death. However, a rim of viable tumor tissue remains from which angiogenesis-dependent regrowth can occur, in part through the mobilization and tumor colonization of circulating endothelial progenitor cells (CEP). Cotreatment with an agent that blocks CEPs, such as a vascular endothelial growth factor pathway-targeting biological antiangiogenic drug, results in enhanced antitumor efficacy. We asked whether an alternative therapeutic modality, low-dose metronomic chemotherapy, could achieve the same result given its CEP-targeting effects. We studied the combination of the vascular disrupting agent OXi4503 with daily administration of CEP-inhibiting, low-dose metronomic cyclophosphamide to treat primary orthotopic tumors with the use of the 231/LM2-4 breast cancer cell line and MeWo melanoma cell line. In addition, CEP mobilization and various tumor characteristics were assessed. We found that daily p.o. low-dose metronomic cyclophosphamide was capable of preventing the CEP spike and tumor colonization induced by OXi4503. This was associated with a decrease in the tumor rim and marked suppression of primary 231/LM2-4 growth in nude as well as severe combined immunodeficient mice. Similar results were found in MeWo-bearing nude mice. The delay in tumor growth was accompanied by significant decreases in microvessel density, perfusion, and proliferation, and a significant increase in tumor cell apoptosis. No overt toxicity was observed. The combination of OXi4503 and metronomic chemotherapy results in prolonged tumor control, thereby expanding the list of therapeutic agents that can be successfully integrated with metronomic low-dose chemotherapy.

In vitro reproduction of noncarious cervical lesions.

STATEMENT OF PROBLEM: A review of the dental literature indicates that noncarious cervical lesions (NCCLs) are formed by erosion, abrasion, and/or abfraction of tooth structure, but their etiology remains scientifically unsubstantiated. PURPOSE: The purpose of this study was to reproduce noncarious cervical lesions in vitro. This study was not designed to statistically quantify the amount of lost tooth structure via abrasion, but rather to attempt to create NCCLs in the various shapes and sizes that are clinically observed. MATERIAL AND METHODS: Three pairs of toothbrush types (generic and name-brand) with soft, medium, or firm bristles were tested with 3 different toothpastes of varying abrasive potentials (low, medium, and high) or with water only, on mounted human teeth with and without simulated gingival tissues (6 toothbrushes x 4 brushing solutions (L, M, H, dentifrices, or water only) x 2 gingival mask conditions = 48 test/control groups of 4 teeth each = 192). RESULTS: The control sets, brushed in water only, demonstrated no visible loss of tooth structure. Each set brushed with toothpaste, regardless of the degree of abrasiveness or toothbrush bristle firmness, demonstrated visible wear at the level of the CEJ. CONCLUSIONS: Significant noncarious cervical lesions were created via horizontal brushing with common commercial toothpaste, while brushing with water only did not create these cervical lesions.

Bisphosphonates and osteonecrosis of the mandible/maxilla in osteoporosis: no reason to panic.

Bisphosphonate (BP) therapy has modified the natural history of many bone metabolic diseases. Amino-bisphosphonates nowadays represent the primary therapeutic choice for the treatment of osteoporosis and for prevention of fractures. Osteonecrosis of the mandible and maxilla (ONJ) is a rare disease usually occurring in cancer patients with bone metastases treated with high doses of intravenous BPs. Some cases have been described in patients taking amino-BPs for osteoporosis, but the specific drug utilized, its dosage and use of the oral route have reduced that risk considerably (estimated at 1/100,000 subjects a year). Prevention of ONJ include good oral hygiene habits in all patients and, in a subject who has been treated for more than three years, conservative dental procedures when possible, an appropriate antibiotic therapy and a careful follow-up when invasive oral interventions are necessary, are recommended by dentists and bone metabolism experts alike.

[Introduction to bisphosphonates. History and functional mechanisms]. / Einführung in die Bisphosphonate. Geschichte und Wirkungsmechanismen.

The development of bisphosphonates is based on our studies in the 1960s on the mechanism of mineralization. It was shown that biological fluids contained mineralization inhibitors which we identified as inorganic pyrophosphate. Pyrophosphate, which, along with longer polyphosphates, has long been known as a water softener due to its inhibition of calcium carbonate formation, also has the ability to inhibit calcium phosphate crystal formation as well as dissolution. When given parenterally (but not orally), they also inhibit experimentally induced mineralization in vivo in animals. Their lack of effectiveness on oral application, as well as for bone destruction, is due to enzymatic cleavage in the body. We therefore sought analogues which had similar properties but were not biologically degraded. The bisphosphonates, which have a P-C-P instead of a P-O-P bond, fulfilled these criteria. They have been known since the middle of the 19th century and have also been used industrially as water softeners. We discovered that they bind to calcium phosphate crystals in the same way as pyrophosphate and inhibit calcium phosphate binding as well as its dissolution. In vivo, they inhibit mineralization as well as bone destruction. While the first process can be explained by a physicochemical mechanism, the second is cellular and involves the inhibition of the formation, lifespan and activity of osteoclasts. The molecular mechanism is dependent on the structure of the bisphosphonate. The structurally more simple molecules without nitrogen incorporate the P-C-P bond in ATP containing molecules and become toxic to the osteoclasts. The more active nitrogen containing bisphosphonates inhibit mevalonate metabolism due to the specific inhibition of farnesyl pyrophosphate synthase. This leads to a reduction in geranylgeranyl pyrophosphate, which is necessary for osteoclast survival.

Nutrient losses from manure and fertilizer applications as impacted by time to first runoff event.

Nutrient losses to surface waters following fertilization contribute to eutrophication. This study was conducted to compare the impacts of fertilization with inorganic fertilizer, swine (Sus scrofa domesticus) manure or poultry (Gallus domesticus) litter on runoff water quality, and how the duration between application and the first runoff event affects resulting water quality. Fertilizers were applied at 35 kg P ha-1, and the duration between application and the first runoff event varied between 1 and 29 days. Swine manure was the greatest risk to water quality 1 day after fertilization due to elevated phosphorus (8.4 mg P L-1) and ammonium (10.3 mg NH4-N L-1) concentrations; however, this risk decreased rapidly. Phosphorus concentrations were 2.6 mg L-1 29 days after fertilization with inorganic fertilizer. This research demonstrates that manures might be more environmentally sustainable than inorganic fertilizers, provided runoff events do not occur soon after application.

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.

Problemas relacionados a medicamentos en un paciente con enfermedad de Cushing / No disponible

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