A distinctive release profile of vancomycin and tobramycin from a new and injectable polymeric dicalcium phosphate dehydrate cement (P-DCPD)

A novel injectable polymeric dicalcium phosphate dehydrate (P-DCPD) cement was developed with superior mechanical strength and excellent cohesion. The purpose of this study was to assess the in vitro performance of P-DCPD loaded with vancomycin (VAN-P), tobramycin (TOB-P) and combination of both (VAN/TOB-P) (10%, w/w). There is a distinctive release profile between VAN and TOB. VAN-P showed decreased initial burst (<30% within 3 d) and sustained VAN release (76% in 28 d). In the presence of TOB (VAN/TOB-P), >90% of VAN was released within 3 d (p < 0.05). Slow and limited TOB release was observed both in TOB-P (<5%) and in TOB/VAN-P (<1%) over 28 d. Zone of inhibition (ZOI) of Staphylococcus aureus growth showed that eluents collected from VAN-P had stronger and longer ZOI (28 d) than that from TOB-P (14 d, p < 0.05). Direct contact of VAN-P, TOB-P and VAN/TOB-P cements displayed persistent and strong ZOI for >3 weeks. Interestingly, the cement residues (28 d after drug release) still maintained strong ZOI ability. P-DCPD with or without antibiotics loading were nontoxic and had no inferior impacts on the growth of osteoblastic MC3T3 cells. VAN-P and TOB-P were injectable. No significant influence on setting time was observed in both VAN-P (11.7 ± 1.9 min) and VAN/TOB-P (10.8 ± 1.5 min) as compared to control (12.2 ± 2.6 min). We propose that a distinctive release profile of VAN and TOB observed is mainly due to different distribution pattern of VAN and TOB within P-DCPD matrix. A limited release of TOB might be due to the incorporation of TOB inside the crystalline lattice of P-DCPD crystals. Our data supported that the bactericidal efficacy of antibiotics-loaded P-DCPD is not only depend on the amount and velocity of antibiotics released, but also probably more on the direct contact of attached bacteria on the degrading cement surface.

Personal Health and Consumer Informatics

To summarize current outstanding research in the field of Personal Health and Consumers Informatics.

A selection of excellent research articles published in 2011 in the field of Personal Health Informatics and Consumer Informatics.

This selection of articles shows that Personal Health Informatics is changing. Indeed, the different solutions tended to the doctors and their interaction, but also tended to the patient in order for him to be more active in his own medical healthcare. The consumer section highlights the development of the social network and the possible limitations.

Personal health and consumer informatics

OBJECTIVES

To summarize current outstanding research in the field of Personal Health and Consumers Informatics.

METHODS

A selection of excellent research articles published in 2011 in the field of Personal Health Informatics and Consumer Informatics.

RESULTS AND CONCLUSIONS

This selection of articles shows that Personal Health Informatics is changing. Indeed, the different solutions tended to the doctors and their interaction, but also tended to the patient in order for him to be more active in his own medical healthcare. The consumer section highlights the development of the social network and the possible limitations.

Decision Support: Time for Collaboration

To summarize current outstanding research in the field of decision support.

A selection of excellent research articles published in 2010 in the field of computerized clinical decision support systems.

This selection of articles shows that deci- sion support systems (DSS) are getting better integrated into the electronic health record systems (EHR) and into the clinician’s workflow. As a result, there is a better collaboration between physicians and DSS, which improves the care of patients.

Decision support: time for collaboration

OBJECTIVES

To summarize current outstanding research in the field of decision support.

METHODS

A selection of excellent research articles published in 2010 in the field of computerized clinical decision support systems.

RESULTS AND CONCLUSIONS

This selection of articles shows that decision support systems (DSS) are getting better integrated into the electronic health record systems (EHR) and into the clinician's workflow. As a result, there is a better collaboration between physicians and DSS, which improves the care of patients.

Identification of a new HLA-DRB1 allele (DRB1*0318) in three members of a Caucasian Spanish family

This communication reports the identification of a new allele HLA-DRB1*03 in three members of a Caucasian Spanish family. The new allele has been officially named HLA-DRB1*0318 by the World Health Organization Nomenclature Committee. The exon 2 sequence of this new allele is identical to that of DRB1*03011 except for the first nucleotide of codon 45. The nucleotide change (C replacing G) leads to the amino acid substitution of glycine to arginine (GGG-->CGG) at position 45. This position of the beta1 domain shows very little polymorphism among DRB1* alleles (nucleotide changes at this position have only been reported for DRB1*1436 and DRB1*0105) and locates in the vicinity of the highly polymorphic position 47, which is a constituent of the groove's pocket interacting with the amino acid position 7 of the antigen peptide. The familial study showed that the new allele was maternally transmitted into the HLA-A*3002, -B*1801, -Cw*0501, -DRB1*0318, -DRB3*0202, -DQB1*0201 haplotype. Interestingly, the two siblings of the family, which were HLA identical and suffered of insulin-dependent diabetes mellitus (IDDM), were carriers of the two HLA haplotypes (DRB1*03/DQB1*0201 and DRB1*04/DQB1*0302) reported as susceptibility markers to IDDM in Caucasians.