USE OF FORCE PLATE ANALYSIS TO EVALUATE THE EFFICACY OF EXTERNAL BEAM RADIATION TO ALLEVIATE OSTEOSARCOMA PAIN

A standard of therapy for osteosarcoma includes amputation with or without adjuvant chemotherapy. There is a subset of dogs with osteosarcoma that are unsuitable for amputation. We evaluated kinetic variables in dogs with appendicular osteosarcoma treated with a single 8 Gy dose of radiation. Eighteen pet dogs with appendicular osteosarcoma received one 8 Gy fraction of palliative radiation on day 0. Force plate measurements and clinical assessments were made on days 0, 7, 14, and 21. Peak vertical forces ( F _z) were recorded for each limb and a symmetric index (SI) was calculated. There were no significant changes in kinetic parameters after one 8 Gy dose of radiation therapy. Nine of these 18 dogs exhibited increased limb function at day 21 based on force plate analysis. Significant factors affecting F _z included gender and tumor location. There was a significant correlation between F _z and response to therapy based on SI at day 21. SI seems to be useful to objectively assess response in this mixed population of dogs. One 8 Gy fraction of radiation therapy alone did not reduce lameness associated with appendicular osteosarcoma, but a subset of dogs did have improved limb function after a single dose.     

EFFECT OF WETNESS LEVEL ON THE SUITABILITY OF WET GAUZE AS A SUBSTITUTE FOR SUPERFLAB® AS A BOLUS MATERIAL FOR USE WITH 6 MV PHOTONS

Despite the availability of commercial tissue equivalent bolus material, wet gauze has an application in radiation therapy to provide superior conformance to irregular contours. Wet gauze bolus has the potential to reduce air gaps between the bolus and surface, which could decrease surface dose if sufficiently large to disrupt electronic equilibrium. Wet gauze bolus is often fabricated and wetness judged qualitatively. We assessed the effect of specific gauze wetness levels, quantified in terms of physical density, at various field sizes with respect to their effectiveness as bolus material compared with Superflab^®. For large fields, >7 × 7 cm² in this study, wet gauze sponges with a physical density of 1.02 g/cm³ performed essentially identical to Superflab^®; at a smaller field size the wet gauze was slightly less effective, likely due to the heterogeneity of the gauze-water matrix. Gauze that was wetter, with a physical density of 1.2 g/cm³, or less wet, with a physical density of 0.75 g/cm³ was not as effective either due to enhanced photon absorption in the wetter sponges, or less effective establishment of electronic equilibrium in the less wet sponges. The presence of an air gap under Superflab^® led to reduced surface dose, especially for small fields and large air gaps. Thus, if Superflab^® use leads to poor contact with the skin, wet gauze having a physical density of 1.02 g/cm³ can be used as a substitute. Judging the water content of wet gauze subjectively is not acceptable as over- or under wetness can lead to decreased effectiveness of the bolus material.     

ASSESSMENT OF THE ACCURACY AND PRECISION OF A PATIENT IMMOBILIZATION DEVICE FOR RADIATION THERAPY IN CANINE HEAD AND NECK TUMORS

The positioning accuracy and precision of a head and neck immobilization device for radiation therapy of tumors in the canine skull was evaluated. Nineteen dogs with a spontaneous tumor of the head were enrolled including 12 with an intracranial mass and seven with an intranasal or maxillary tumor. Three hundred thirty-three pairs of orthogonal digital portal radiographs were analyzed to assess patient displacement in the cranial–caudal, lateral, and dorso-ventral directions. The mean systematic displacement was 0.8, 1, and 0.9 mm. The mean random displacement was 1.9, 1.6, and 1.5 mm. These values resulted in an overall displacement of 2.1 mm in the cranial–caudal direction, 1.8 mm in the lateral direction, and 1.7 mm in the dorsal–ventral direction. The mean displacement value of the three dimensional (3D) vector was 2.4 mm with a standard deviation of 2.1. Ninety-five percent of all vectors were <6.4 mm. This study quantifies the precision and accuracy of this particular positioning device. Knowing the limitations and setup variability of the system being used to set patients up for daily radiotherapy is paramount to planning and delivering appropriate radiation doses, especially as more complex treatment methods are used.     

Principles and Practice of Therapeutic Exercise for Horses

Physical therapists are an integral component of the medical team in human health care. They are backed by a solid foundation of basic science and clinical research. Veterinarians have only recently begun to incorporate physical therapy into clinical practice, but without formal research that validates therapeutic interventions specific to equine patients. The purpose of this article is to present a series of therapeutic exercises adapted for horses based on knowledge and experience of human physical therapy, equine biomechanics, and the types of movement dysfunction commonly seen in the performance horse. Injuries, lameness and musculoskeletal pain syndromes, frequently encountered in equine practice, are disorders that may be successfully addressed with physical therapy. Incorporating standard therapeutic interventions based on clinical success in humans, basic science research, or expert opinion is possible with the understanding that these techniques will ultimately be accepted or refuted when their success or failure is formally documented. This review is designed to stimulate discussion and encourage research that will add to the knowledge base and lead to effective therapeutic protocols in the equine patient.     

A new cell culture protocol for enrichment and genetic modification of adult canine Schwann cells suitable for peripheral nerve tissue engineering

Easily applicable techniques are presented to obtain high numbers of enriched canine Schwann cells (cSC) in a short time-window. The potential of adult SC for tissue engineering of peripheral nerves and ex vivo gene therapy is obvious from physiological events taking place after peripheral nerve transection [Haastert, K., Grothe, C., 2007. Gene therapy in peripheral nerve reconstruction approaches. Curr. Gene Ther. 7, 221-228]. The presented techniques were modified from a protocol for cultivation and expansion of adult cSC by others [Pauls, J., Nolte, C., Forterre, F., Brunnberg, L., 2004. Cultivation and expansion of canine Schwann cells using reexplantation. Berl. Munch. Tierarztl. Wochenschr. 117, 341-352] and own experiences in rodent and human SC cultivation and transfection [Haastert, K., Mauritz, C., Chaturvedi, S., Grothe, C., 2007. Human and rat adult Schwann cell cultures: fast and efficient enrichment and highly effective non-viral transfection protocol. Nat. Protoc. 2, 99-104]. A purity of about 80% cSC achieved by immunopanning techniques and selective culture conditions is 2.5 fold higher as previously reported (Pauls et al., 2004). Additionally, highly enriched cSC populations are available in 3-4 weeks, only half the time period reported previously (Pauls et al., 2004). Furthermore, electroporation and genetic modification of cSC is reported for the first time.     

Fluid therapy with artificial colloids: complications and controversies

Objectives To discuss the advantages and disadvantages of colloidal therapy in veterinary medicine. Databases used MEDLINE (1966–present), Commonwealth Agricultural Bureau Abstracts (1973–present), personal files.     

基于投入产出的太湖流域水足迹分析

以经济社会较为发达的太湖流域为研究区,基于2007年流域内各省（市）的水足迹投入产出表,分析了3次产业的用水系数、水足迹和净外部水足迹.结果表明,2007年,流域内第一产业的完全用水系数最大,用水主要集中在直接用水方面;第二、第三产业用水主要集中在间接用水方面;2007年太湖流域水足迹为453.30亿m3,净外部水足迹为63.98亿m3,占全流域水足迹的14％.