The principal challenge for bone therapy is to deliver an effective dose of therapeutic agent (for example antibiotic or anti-cancer drug) to the affected site within bone, while sparing other organs. The solution to this dilemma is to deliver drug locally within the bone; hence various surface/therapeutic modifications of the conventional bone implants have been suggested to achieve this. Implants composed of biocompatible materials and loaded with active therapeutics thus provide one possible option for effective bone therapy. This chapter showcases the challenges that an electrochemically nano-engineered bone implant based on titania nanotubes must overcome to survive and deliver therapeutics in conditions such as infections and cancer of bone. The fabrication of titania nanotubes, the therapeutic loading and release, ex-vivo and in vivo investigations; all are reviewed in terms of effectiveness for therapeutic action. Also discussed are the potential advances of titania nanotube technology and the future research directions to address additional clinical problems.

The use of methylmalonyl-CoA epimerase (MCEE) to improve stereoselectivity in crotonase-mediated biocatalysis is exemplified by the coupling of MCEE, crotonyl-CoA carboxylase reductase and carboxymethylproline synthase in a three-enzyme one-pot sequential synthesis of functionalised C-5 carboxyalkylprolines starting from crotonyl-CoA and carbon dioxide.

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Enniatins (ENs), a group of antibiotics commonly produced by various strains of Fusarium, are six-membered cyclic depsipeptides formed by the union of three molecules of D-α-hydroxyisovaleric acid and three N-methyl-L-amino acids. The endophyte Fusarium tricinctum Corda was isolated from the fruits of Hordeum sativum Jess. and cultivated on a rice medium. The fungal metabolites were extracted with methanol and were identified, employing liquid chromatography-mass spectrometry as ENs A, A1, B, B1, B2 and Q. EN Q is a new analog of EN A and the occurrence of EN B2 is reported for the first time from this endophyte, in addition to four well-known ENs (A, A1, B and B1). The methanol extract of F. tricinctum showed mild antibacterial and antileishmanial activities. Additionally the tested extract displayed inhibition of the activity of thioredoxin reductase enzyme of Plasmodium falciparum.

Enniatins (ENs), a group of antibiotics commonly produced by various strains of Fusarium, are six-membered cyclic depsipeptides formed by the union of three molecules of D-α-hydroxyisovaleric acid and three N-methyl-L-amino acids. The endophyte Fusarium tricinctum Corda was isolated from the fruits of Hordeum sativum Jess. and cultivated on a rice medium. The fungal metabolites were extracted with methanol and were identified, employing liquid chromatography-mass spectrometry as ENs A, A1, B, B1, B2 and Q. EN Q is a new analog of EN A and the occurrence of EN B2 is reported for the first time from this endophyte, in addition to four well-known ENs (A, A1, B and B1). The methanol extract of F. tricinctum showed mild antibacterial and antileishmanial activities. Additionally the tested extract displayed inhibition of the activity of thioredoxin reductase enzyme of Plasmodium falciparum.

Purpose: Domperidone (Dp) is a dopamine (D2) receptor antagonist widely used as gastrointestinal prokinetic and antiemetic drug. It is practically insoluble in water and it is also a weak base having poor dissolution rates at relatively high pH values. The objective of this study is to enhance its dissolution via formulation in gastro-retentive floating tablets. While the system is floating on the gastric contents, the drug is released slowly at a desirable rate imparting a sustained-release effect. Methods: Several hydrophilic and hydrophobic polymers were used in the preparation of tablets matrices. Tablets were evaluated for their physical properties including weight uniformity, drug content, friability, hardness, thickness, floating time as well as the in vitro drug release. Results: The order of sustaining Dp release was exhibited by carbopol 934P > Eudragit RLPO > Eudragit RS100 > Eudragit RL100 > ethyl cellulose> hyroxypropylmethyl cellulose 15000>sodium alginate. Increasing the polymer/Dp ratio in the tablets increased the sustaining effect. Tablets containing 30% and 40 % (w/w) of either HPMC 15000 or sodium alginate showed the best floating properties and release profiles. Analysis of release data revealed that formulae containing cabopol 934P showed zero-order kinetics while the other formulae showed Higuchi model kinetics. All formulae showed non-fickian release pattern. Conclusion: formulation of floating tablets has successfully improved and sustained domperidone release over a time period of 12 hours. This may be beneficial in prolonging the prophylaxis against nausea and vomiting for a longer time eliminating the need for multiple dosing which also improves the patient compliance. Future work includes adding an immediate release component for instant prokinetic effect and in vivo comparative studies.

Purpose: Domperidone (Dp) is a dopamine (D2) receptor antagonist widely used as gastrointestinal prokinetic and antiemetic drug. It is practically insoluble in water and it is also a weak base having poor dissolution rates at relatively high pH values. The objective of this study is to enhance its dissolution via formulation in gastro-retentive floating tablets. While the system is floating on the gastric contents, the drug is released slowly at a desirable rate imparting a sustained-release effect. Methods: Several hydrophilic and hydrophobic polymers were used in the preparation of tablets matrices. Tablets were evaluated for their physical properties including weight uniformity, drug content, friability, hardness, thickness, floating time as well as the in vitro drug release. Results: The order of sustaining Dp release was exhibited by carbopol 934P > Eudragit RLPO > Eudragit RS100 > Eudragit RL100 > ethyl cellulose> hyroxypropylmethyl cellulose 15000>sodium alginate. Increasing the polymer/Dp ratio in the tablets increased the sustaining effect. Tablets containing 30% and 40 % (w/w) of either HPMC 15000 or sodium alginate showed the best floating properties and release profiles. Analysis of release data revealed that formulae containing cabopol 934P showed zero-order kinetics while the other formulae showed Higuchi model kinetics. All formulae showed non-fickian release pattern. Conclusion: formulation of floating tablets has successfully improved and sustained domperidone release over a time period of 12 hours. This may be beneficial in prolonging the prophylaxis against nausea and vomiting for a longer time eliminating the need for multiple dosing which also improves the patient compliance. Future work includes adding an immediate release component for instant prokinetic effect and in vivo comparative studies.

Purpose: Domperidone (Dp) is a dopamine (D2) receptor antagonist widely used as gastrointestinal prokinetic and antiemetic drug. It is practically insoluble in water and it is also a weak base having poor dissolution rates at relatively high pH values. The objective of this study is to enhance its dissolution via formulation in gastro-retentive floating tablets. While the system is floating on the gastric contents, the drug is released slowly at a desirable rate imparting a sustained-release effect. Methods: Several hydrophilic and hydrophobic polymers were used in the preparation of tablets matrices. Tablets were evaluated for their physical properties including weight uniformity, drug content, friability, hardness, thickness, floating time as well as the in vitro drug release. Results: The order of sustaining Dp release was exhibited by carbopol 934P > Eudragit RLPO > Eudragit RS100 > Eudragit RL100 > ethyl cellulose> hyroxypropylmethyl cellulose 15000>sodium alginate. Increasing the polymer/Dp ratio in the tablets increased the sustaining effect. Tablets containing 30% and 40 % (w/w) of either HPMC 15000 or sodium alginate showed the best floating properties and release profiles. Analysis of release data revealed that formulae containing cabopol 934P showed zero-order kinetics while the other formulae showed Higuchi model kinetics. All formulae showed non-fickian release pattern. Conclusion: formulation of floating tablets has successfully improved and sustained domperidone release over a time period of 12 hours. This may be beneficial in prolonging the prophylaxis against nausea and vomiting for a longer time eliminating the need for multiple dosing which also improves the patient compliance. Future work includes adding an immediate release component for instant prokinetic effect and in vivo comparative studies.

Purpose: Domperidone (Dp) is a dopamine (D2) receptor antagonist widely used as gastrointestinal prokinetic and antiemetic drug. It is practically insoluble in water and it is also a weak base having poor dissolution rates at relatively high pH values. The objective of this study is to enhance its dissolution via formulation in gastro-retentive floating tablets. While the system is floating on the gastric contents, the drug is released slowly at a desirable rate imparting a sustained-release effect. Methods: Several hydrophilic and hydrophobic polymers were used in the preparation of tablets matrices. Tablets were evaluated for their physical properties including weight uniformity, drug content, friability, hardness, thickness, floating time as well as the in vitro drug release. Results: The order of sustaining Dp release was exhibited by carbopol 934P > Eudragit RLPO > Eudragit RS100 > Eudragit RL100 > ethyl cellulose> hyroxypropylmethyl cellulose 15000>sodium alginate. Increasing the polymer/Dp ratio in the tablets increased the sustaining effect. Tablets containing 30% and 40 % (w/w) of either HPMC 15000 or sodium alginate showed the best floating properties and release profiles. Analysis of release data revealed that formulae containing cabopol 934P showed zero-order kinetics while the other formulae showed Higuchi model kinetics. All formulae showed non-fickian release pattern. Conclusion: formulation of floating tablets has successfully improved and sustained domperidone release over a time period of 12 hours. This may be beneficial in prolonging the prophylaxis against nausea and vomiting for a longer time eliminating the need for multiple dosing which also improves the patient compliance. Future work includes adding an immediate release component for instant prokinetic effect and in vivo comparative studies.

Domperidone is a dopamine antagonist antiemetic drug, water-insoluble and weakly basic with poor dissolution rates at high pH values. The current study aimed to improve such dissolution via adsorbates and co-adsorbates formulations. Adsorbates of drug with Avicel PH 101, Florite R and Aerosil 200 were prepared in different weight ratios by physical mixing, grinding and solvent deposition methods. Co-adsorbates of drug with Tween 80 and Aerosil 200 were prepared by solvent deposition method in different weight ratios. These systems were characterized using Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), powder X-ray diffractometry (P-XRD) and in-vitro dissolution. The results showed marked enhancement of domperidone dissolution at both pH1.2 and pH6.8 (7 fold and 5 fold, respectively) compared to drug alone.