Conducting Informal Discovery of a Party\u27s Former Employees: Legal and Ethical Concerns and Constraints

This Article identifies and critiques existing sources of confusion in the law and proposes revised and alternative discovery procedures to provide equal access to information possessed by ex-employees, while simultaneously safeguarding the integrity of that information. Its primary emphasis is on federal jurisprudence, although important points of consensus and departure between state and federal law are noted, as appropriate. Part I explains the issues that arise in informal discovery, and the difficulties with clearly resolving those issues given the conflicting state of the law. Part II discusses application of the attorney-client privilege to communications between corporate counsel and former employees, concluding that the privilege should not shield the content of such communications from discovery by opposing counsel. Because the attorney-client privilege issue and the debate over ex parte contact both turn on whether a former employee is a party to the litigation, an exposition of the ethical concerns of ex parte contact follows in Part III, which concludes that ex parte contact by opposing counsel should be allowed. Part IV examines the applicability of the work product doctrine in shielding from discovery certain tangible materials related to the interview. This Article advocates absolute immunity from discovery for attorney notes and memoranda, and for collections of documents selected by counsel for discussion with former employees; limited discovery of signed witness statements generated pursuant to the interview; and fairly broad discovery of the content of counsel\u27s questions and statements during the interview. The proposed discovery guidelines in the Conclusion are offered with the ambitious, if not elusive, goal of reconciling the competing interests and policies that rouse litigants to battle when informal discovery is conducted of former employees, while simultaneously giving due regard to the pragmatic impact that new or revised rules may have on the litigants and the adversarial process. The overriding objective is to provide equal access by all parties to the information possessed by former employees, while at the same time providing mechanisms to deter, and if necessary to reveal, inappropriate manipulation of these potential witnesses by counsel

Gentamicin loaded beta-tricalcium phosphate/gelatin composite microspheres as biodegradable bone fillers

In this study, novel composite bone fillers with microspherical shape, biodegradable property, and antibacterial effect were designed and prepared. Various fillers with different beta-tricalcium phosphate (beta-TCP)/gelatin (G)/glutaraldeyde (GA) compositions were loaded with a model antibiotic, gentamicin. The effect of composition and preparation conditions on the release of gentamicin was investigated in in vitro conditions. Complete release were observed in 12 h for pure beta-TCP powder, and this period was extended up to 96 h as the gelatin content increased in the microspheres. Morphological and chemical structures of the microspheres, before and after the release studies, were investigated by scanning electron microscopy and Fourier transform infrared, respectively. Antibacterial activities were examined against Escherichia coli by using disc diffusion method and promising results were obtained. It is proposed that these novel beta-TCP/G/GA microspheres can be applied locally to prevent and/or eliminate infection that might occur around a defected region of hard tissue and supports the healing process. POLYM. COMPOS., 2012. (c) 2012 Society of Plastics Engineer

Heparin/Chitosan/Alginate Complex Scaffolds as Wound Dressings: Characterization and Antibacterial Study Against Staphylococcus epidermidis

Infected wounds are global healthcare problems since they can lead to dysfunctioning in organs and even result in death in severe cases. In this study, antibacterial wound dressings were prepared to prevent possible infection at the damaged host region. For this purpose, three natural polymers namely heparin, chitosan and alginate were used as anionic, cationic and sulfated polysaccharides, respectively, due to their versatile properties as being nontoxic, biocompatible, biodegradable and antibacterial. Heparin/chitosan/alginate based complex polyelectrolyte scaffolds containing different amounts of heparin were prepared by freeze drying technique. The effects of calcium chloride, which is used as crosslinker for alginate, on the stability of scaffolds were tested. Presence of functional groups and morphological structures of the scaffolds were examined in detail by using FTIR, XPS and SEM. Antibacterial activities against Staphylococcus epidermidis (S. epidermidis) were investigated under in vitro conditions. Presence and the amount of heparin in the scaffolds significantly enhanced the antibacterial activities. The results demonstrated that heparin/chitosan/alginate polyelectrolyte scaffolds have very high potential to be used as therapeutic wound dressings

Zero valent zinc nanoparticles promote neuroglial cell proliferation: A biodegradable and conductive filler candidate for nerve regeneration

Regeneration of nerve, which has limited ability to undergo self-healing, is one of the most challenging areas in the field of tissue engineering. Regarding materials used in neuroregeneration, there is a recent trend toward electrically conductive materials. It has been emphasized that the capacity of conductive materials to regenerate such tissue having limited self-healing ability improves their clinical utility. However, there have been concerns about the safety of materials or fillers used for conductance due to their lack of degradability. Here, we attempt to use poly(epsilon-caprolactone) (PCL) matrix consisting of varying proportions of zero valent zinc nanoparticles (Zn NPs) via electrospinning. These conductive, biodegradable, and bioactive materials efficiently promoted neuroglial cell proliferation depending on the amount of Zn NPs present in the PCL matrix. Chemical characterizations indicated that the incorporated Zn NPs do not interact with the PCL matrix chemically and that the Zn NPs improved the tensile properties of the PCL matrix. All composites exhibited linear conductivity under in vitro conditions. In vitro cell culture studies were performed to determine the cytotoxicity and proliferative efficiency of materials containing different proportions of Zn NPs. The results were obtained to explore new conductive fillers that can promote tissue regeneration

Poly(epsilon-caprolactone) composites containing gentamicin-loaded beta-tricalcium phosphate/gelatin microspheres as bone tissue supports

In this work, novel antibacterial composites were prepared by using poly(epsilon-caprolactone) (PCL) as the main matrix material, and gentamicin-loaded microspheres composed of beta-tricalcium phosphate (beta-TCP) and gelatin. The purpose is to use this biodegradable material as a support for bone tissue. This composite system is expected to enhance bone regeneration by the presence of beta-TCP and prevent a possible infection that might occur around the defected bone region by the release of gentamicin. The effects of the ratio of the beta-TCP/gelatin microspheres on the morphological, mechanical, and degradation properties of composite films as well as in vitro antibiotic release and antibacterial activities against Escherichia coli and Staphylococcus aureus were investigated. The results showed that the composites of PCL and beta-TCP/gelatin microspheres had antibacterial activities for both bacteria. (C) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 201

Semi-IPN Chitosan/PEG Microspheres and Films for Biomedical Applications: Characterization and Sustained Release Optimization

WOS: 000308847100016Micro drug carriers are one of the efficient methods for local or systemic cancer treatment. In this study, the aim was to prepare a novel semi-interpenetrated (semi-IPN) micro system by using biocompatible chitosan (CH) and polyethylene glycol (PEG). Various combinations of the systems were prepared and loaded with a model chemotherapeutic drug, methotrexate (MTX), and the effects of composition on the properties and the release behavior of microspheres were examined. Also, the mechanical and thermal properties were examined on film forms of similar compositions. Increase in cross-linking caused a decrease in particle size of CH from 144 to 91 mu m, while the addition of PEG caused an increase up to 163 mu m. Elastic modulus values of the films first increased and then decreased parallel to PEG content. In vitro studies showed faster MTX release from semi-IPN CH-PEG microspheres as compared to pure CH ones. Promising results were obtained in the development of biodegradable drug vehicles

Poly(epsilon-caprolactone) Composite Scaffolds Loaded with Gentamicin-Containing beta-Tricalcium Phosphate/Gelatin Microspheres for Bone Tissue Engineering Applications

In this study, novel poly(epsilon-caprolactone) (PCL) composite scaffolds were prepared for bone tissue engineering applications, where gentamicin-loaded -tricalcium phosphate (-TCP)/gelatin microspheres were added to PCL. The effects of the amount of -TCP/gelatin microspheres added to the PCL scaffold on various properties, such as the gentamicin release rate, biodegradability, morphology, mechanical strength, and pore size distribution, were investigated. A higher amount of filler caused a reduction in the mechanical properties and an increase in the pore size and led to a faster release of gentamicin. Human osteosarcoma cells (Saos-2) were seeded on the prepared composite scaffolds, and the viability of cells having alkaline phosphatase (ALP) activity was observed for all of the scaffolds after 3 weeks of incubation. Cell proliferation and differentiation enhanced the mechanical strength of the scaffolds. Promising results were obtained for the development of bone cells on the prepared biocompatible, biodegradable, and antimicrobial composite scaffolds. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40110

In Vivo Performance of Poly(epsilon-caprolactone) Constructs Loaded with Gentamicin Releasing Composite Microspheres for Use in Bone Regeneration

For materials used in the production of dental and orthopedic implants or scaffolds for bone tissue regeneration, the properties such as capacity to enhance cell attachment and proliferation, and antimicrobial activity to prevent biofilm formation are very important to improve the clinical utility of the material. In this study, poly(epsilon-caprolactone) (PCL) sponges with antimicrobial activity were prepared by incorporating gentamicin loaded beta-tricalcium phosphate (beta-TCP)-Gelatin microspheres, and in vivo performances were studied. These composite systems are expected to enhance bone regeneration due to beta-TCP and prevent a possible infection by releasing gentannicin in the host location. The effects of gentamicin and beta-TCP/Gelatin microspheres in the sponge structure were studied in vivo by applying them on iliac crest defects of rabbits. Histological analyses after 8 weeks of implantation showed that the composite constructs performed significantly better in bone healing than those with antibiotic-free microspheres. Also, the PCL constructs carrying beta-TCP/Gelatin microspheres led to better bone formation than the pristine PCL scaffolds. Push-out tests demonstrated better integration of the constructs with the tissue indicating high level of material-tissue integration. This study indicates the importance of the presence of antibiotics and beta-TOP/Gelatin in the scaffolds to achieve better and faster healing in bone defects than pristine scaffolds

Semi-IPN Chitosan/PEG Microspheres and Films for Biomedical Applications: Characterization and Sustained Release Optimization

WOS: 000308847100016Micro drug carriers are one of the efficient methods for local or systemic cancer treatment. In this study, the aim was to prepare a novel semi-interpenetrated (semi-IPN) micro system by using biocompatible chitosan (CH) and polyethylene glycol (PEG). Various combinations of the systems were prepared and loaded with a model chemotherapeutic drug, methotrexate (MTX), and the effects of composition on the properties and the release behavior of microspheres were examined. Also, the mechanical and thermal properties were examined on film forms of similar compositions. Increase in cross-linking caused a decrease in particle size of CH from 144 to 91 mu m, while the addition of PEG caused an increase up to 163 mu m. Elastic modulus values of the films first increased and then decreased parallel to PEG content. In vitro studies showed faster MTX release from semi-IPN CH-PEG microspheres as compared to pure CH ones. Promising results were obtained in the development of biodegradable drug vehicles