A survey of United States dairy hoof care professionals on costs associated with treatment of foot disorders.

The objective of this study was to collect information regarding hoof care professionals' billing practices and to gather their opinions about foot disorders and the value of their prevention. Responses were gathered from veterinarians (n = 18) and hoof trimmers (n = 116) through both online and paper survey platforms. Because of the limited number of respondents, veterinarian responses were not further analyzed. Of the 6 foot disorders included in the survey, the treatment cost per case was greatest for toe ulcers (mean ± standard deviation; $20.2 ± 8.5), sole ulcers ($19.7 ± 8.6), white line disease ($19.5 ± 8.1), and thin soles ($18.1 ± 8.1), and least for infectious disorders (foot rot and digital dermatitis; $8.0 ± 7.6 and $7.5 ± 9.6, respectively). Of the disorders, digital dermatitis represented most of the foot disorder cases treated by respondents over the past year (43.9 ± 20.4%), whereas toe ulcers and thin soles represented the least (5.3 ± 4.1 and 5.3 ± 5.7%, respectively). Respondents that served mostly large herds (>500 lactating cows) reported a lower prevalence of digital dermatitis (31.6 ± 4.2 vs. 44.4 ± 3.4 and 46.7 ± 3.2% in small and medium herds, respectively) and a higher prevalence of sole ulcers (23.1 ± 3.0 vs. 13.4 ± 2.4 and 13.3 ± 2.3% in small and medium herds, respectively). Region of the United States (Northeast, Midwest, or other) also influenced foot disorder prevalence; respondents from the Northeast reported more sole ulcers than respondents from other regions (22.1 ± 2.3 vs. 12.4 ± 3.3%). When respondents were asked which disorder was associated with the greatest total cost per case to the producer (treatment and labor costs plus the reduction in milk yield, reduced reproductive performance, and so on), hoof trimmers ranked digital dermatitis as having the greatest total cost per case and thin soles as having the least total cost per case. Finally, respondents indicated that the most important benefits of reducing foot disorders were enhanced animal welfare and increased milk production, whereas the least important benefit was reduced veterinary and hoof trimmer fees. Results from this survey can be used to improve the accuracy of foot disorder cost estimates and contribute to better decision-making regarding both foot disorder treatment and prevention.

Employing mesenchymal stem cells to support tumor-targeted delivery of extracellular vesicle (EV)-encapsulated microRNA-379.

Adult Mesenchymal Stem Cells (MSCs) have a well-established tumor-homing capacity, highlighting potential as tumor-targeted delivery vehicles. MSCs secrete extracellular vesicle (EV)-encapsulated microRNAs, which play a role in intercellular communication. The aim of this study was to characterize a potential tumor suppressor microRNA, miR-379, and engineer MSCs to secrete EVs enriched with miR-379 for in vivo therapy of breast cancer. miR-379 expression was significantly reduced in lymph node metastases compared to primary tumor tissue from the same patients. A significant reduction in the rate of tumor formation and growth in vivo was observed in T47D breast cancer cells stably expressing miR-379. In more aggressive HER2-amplified HCC-1954 cells, HCC-379 and HCC-NTC tumor growth rate in vivo was similar, but increased tumor necrosis was observed in HCC-379 tumors. In response to elevated miR-379, COX-2 mRNA and protein was also significantly reduced in vitro and in vivo. MSCs were successfully engineered to secrete EVs enriched with miR-379, with the majority found to be of the appropriate size and morphology of exosomal EVs. Administration of MSC-379 or MSC-NTC cells, or EVs derived from either cell population, resulted in no adverse effects in vivo. While MSC-379 cells did not impact tumor growth, systemic administration of cell-free EVs enriched with miR-379 was demonstrated to have a therapeutic effect. The data presented support miR-379 as a potent tumor suppressor in breast cancer, mediated in part through regulation of COX-2. Exploiting the tumor-homing capacity of MSCs while engineering the cells to secrete EVs enriched with miR-379 holds exciting potential as an innovative therapy for metastatic breast cancer.

Design and performance of a small-animal imaging system using synthetic collimation.

This work outlines the design and construction of a single-photon emission computed tomography imaging system based on the concept of synthetic collimation. A focused multi-pinhole collimator is constructed using rapid-prototyping and casting techniques. The collimator projects the centre of the field of view (FOV) through 46 pinholes when the detector is adjacent to the collimator, with the number reducing towards the edge of the FOV. The detector is then moved further from the collimator to increase the magnification of the system. The object distance remains constant, and each new detector distance is a new system configuration. The level of overlap of the pinhole projections increases as the system magnification increases, but the number of projections subtended by the detector is reduced. There is no rotation in the system; a single tomographic angle is used in each system configuration. Image reconstruction is performed using maximum-likelihood expectation-maximization and an experimentally measured system matrix. The system matrix is measured for each configuration on a coarse grid, using a point source. The pinholes are individually identified and tracked, and a Gaussian fit is made to each projection. The coefficients of these fits are used to interpolate the system matrix. The system is validated experimentally with a hot-rod phantom. The Fourier crosstalk matrix is also measured to provide an estimate of the average spatial resolution along each axis over the entire FOV. The 3D synthetic-collimator image is formed by estimating the activity distribution within the FOV and summing the activities in the voxels along the axis perpendicular to the collimator face.

Relationship between CCL5 and transforming growth factor-ß1 (TGFß1) in breast cancer.

PURPOSE: Investigate circulating CCL5 in breast cancer patients and healthy controls, along with gene expression levels in corresponding tumour tissue and isolated primary stromal cells. Hormonal control of CCL5, and a potential relationship with TGFß1, was also investigated. METHODS: Circulating levels of CCL5 and TGFß1 were measured in 102 breast cancer patients and 66 controls using ELISA. Gene expression levels (CCL5, CCR5, TGFß1, TGFßRII) were quantified in corresponding tumour tissue (n = 43), normal tissue (n = 16), and isolated tumour (n = 22) and normal (n = 3) stromal cells using RQ-PCR. CCL5 and circulating menstrual hormones (LH, FSH, Oestradiol, Progesterone) were analysed in serum samples from healthy, premenopausal volunteers (n = 60). RESULTS: TGFß1 was significantly higher in breast cancer patients (Mean(SEM) 27.4(0.9)ng/ml) compared to controls (14.9(0.9)ng/ml). CCL5 levels decreased in the transition from node negative (59.6(3.7)ng/ml) to node positive disease (40.5(6.3)ng/ml) and increased again as the number of positive lymph nodes increased (⩾3 positive 50.95(9.8)ng/ml). A significant positive correlation between circulating CCL5 and TGFß1 (r = 0.423, p<0.0001) was observed, and mirrored at the gene expression level in tumour tissue from the same patients (r = 0.44, p<0.001). CCL5, CCR5 and TGFß1 expression was significantly higher in tumour compared to normal breast tissue (p < 0.001). A significant negative correlation was observed between circulating CCL5, Oestradiol and Progesterone (r = -0.50, r = -0.39, respectively, p < 0.05). CONCLUSION: CCL5 expression is elevated in the tumour microenvironment. The data support a role for hormonal control of circulating CCL5 and also highlight a potentially important relationship between CCL5 and TGFß1 in breast cancer.

Mesenchymal stem cells and cancer: tumor-specific delivery vehicles or therapeutic targets?

Mesenchymal stem cells (MSCs) are a subset of nonhematopoietic multipotent cells found primarily within the bone marrow stroma. The ability of MSCs to specifically home to sites of tumors and their metastases, while escaping host immune surveillance, holds tremendous promise for tumor-targeted delivery of therapeutic agents. Concerns that MSCs may have an inherent capacity for transformation have led to a number of studies investigating their stability in vitro, as significant ex vivo expansion will be necessary to yield the number of cells required for therapeutic applications. MSCs have also been seen to influence the morphology and proliferation of cells within their vicinity through a combination of cell-to-cell interactions and the secretion of chemoattractant cytokines. Understanding interactions between MSCs and tumor cells is required to support realization of their clinical potential. This review discusses MSCs and cancer in terms of (1) potential for transformation and de novo tumor formation, (2) interactions with epithelial cancer cells in tumor establishment, and (3) potential role after engraftment at the site of an established tumor. Elucidation of any potential negative effect of MSCs in the tumor setting will support development of protocols to minimize these effects while taking full advantage of the remarkable tumor-homing capacity of these cells.

Potential role of mesenchymal stem cells (MSCs) in the breast tumour microenvironment: stimulation of epithelial to mesenchymal transition (EMT).

Bone marrow-derived mesenchymal stem cells (MSCs) are known to specifically migrate to and engraft at tumour sites. Understanding interactions between cancer cells and MSCs has become fundamental to determining whether MSC-tumour interactions should be harnessed for delivery of therapeutic agents or considered a target for intervention. Breast Cancer Cell lines (MDA-MB-231, T47D & SK-Br3) were cultured alone or on a monolayer of MSCs, and retrieved using epithelial specific magnetic beads. Alterations in expression of 90 genes associated with breast tumourigenicity were analysed using low-density array. Expression of markers of epithelial-mesenchymal transition (EMT) and array results were validated using RQ-PCR. Co-cultured cells were analysed for changes in protein expression, growth pattern and morphology. Gene expression and proliferation assays were also performed on indirect co-cultures. Following direct co-culture with MSCs, breast cancer cells expressed elevated levels of oncogenes (NCOA4, FOS), proto-oncogenes (FYN, JUN), genes associated with invasion (MMP11), angiogenesis (VEGF) and anti-apoptosis (IGF1R, BCL2). However, universal downregulation of genes associated with proliferation was observed (Ki67, MYBL2), and reflected in reduced ATP production in response to MSC-secreted factors. Significant upregulation of EMT specific markers (N-cadherin, Vimentin, Twist and Snail) was also observed following co-culture with MSCs, with a reciprocal downregulation in E-cadherin protein expression. These changes were predominantly cell contact mediated and appeared to be MSC specific. Breast cancer cell morphology and growth pattern also altered in response to MSCs. MSCs may promote breast cancer metastasis through facilitation of EMT.

Monocyte chemotactic protein-1 secreted by primary breast tumors stimulates migration of mesenchymal stem cells.

PURPOSE: Major barriers to effective adenovirus-based gene therapy include induction of an immune response and tumor-specific targeting of vectors. The use of mesenchymal stem cells (MSC) as systemic delivery vehicles for therapeutic genes has been proposed as a result of their combined ability to home in on the tumor site and evade the host immune response. This study is aimed at investigating factors mediating homing of human MSCs to breast cancer primary cultures and cell lines in vitro and in vivo. EXPERIMENTAL DESIGN: Fluorescently labeled MSCs were given to mice bearing breast cancer xenografts, and tumor tissue was harvested to detect MSC engraftment. MSC migration in response to primary breast tumors in vitro was quantified, and chemokines secreted by tumor cells were identified. The role of monocyte chemotactic protein-1 (MCP-1) in cell migration was investigated using antibodies and standards of the chemokine. Serum MCP-1 was measured in 125 breast cancer patients and 86 healthy controls. RESULTS: Engrafted MSCs were detected in metastatic breast tumors in mice after systemic administration. There was a significant increase in MSC migration in response to primary breast tumor cells in vitro (6-fold to 11-fold increase). Tumor explants secreted a variety of chemokines including GROalpha, MCP-1, and stromal cell-derived factor-1alpha. An MCP-1 antibody caused a significant decrease (37-42%) in MSC migration to tumors. Serum MCP-1 levels were significantly higher in postmenopausal breast cancer patients than age-matched controls (P < 0.05). CONCLUSIONS: These results highlight a role for tumor-secreted MCP-1 in stimulating MSC migration and support the potential of these cells as tumor-targeted delivery vehicles for therapeutic agents.

Sodium iodide symporter-mediated radioiodide imaging and therapy of ovarian tumor xenografts in mice.

Ovarian cancer represents the fifth leading cause of cancer death among women in the United States, with >16 000 deaths expected this year. This study was carried out to investigate the potential of sodium iodide symporter (NIS)-mediated radioiodide therapy as a novel approach for ovarian cancer treatment. Radioiodide is routinely and effectively used for the treatment of benign and malignant thyroid disease as a result of native thyroidal expression of NIS, which mediates iodide uptake. In vitro gene transfer studies in ovarian cancer cells revealed a 12- and five-fold increase in iodide uptake when transduced with Ad/CMV/NIS or Ad/MUC1/NIS, respectively. Western blot/immunohistochemistry confirmed NIS protein expression. In vivo ovarian tumor xenografts were infected with the adenoviral constructs. (123)I imaging revealed a clear image of the CMV/NIS-transduced tumor, with a less intense image apparent following infection with MUC1/NIS. Therapeutic doses of (131)I following CMV/NIS infection caused a mean 53% reduction in tumor volume (P<0.0001). MUC1/NIS-transduced tumors did not regress, although at 8 weeks following therapy, tumor volume was significantly less that of control animals (166 versus 332%, respectively, P<0.05). This study represents a promising first step investigating the potential for NIS-mediated radioiodide imaging and therapy of ovarian tumors.

Identification of sources of Salmonella organisms in a veterinary teaching hospital and evaluation of the effects of disinfectants on detection of Salmonella organisms on surface materials.

OBJECTIVE: To determine sources of Salmonella organisms in a veterinary teaching hospital, compare bacterial culture with polymerase chain reaction (PCR) testing for detection of Salmonella organisms in environmental samples, and evaluate the effects of various disinfectants on detection of Salmonella organisms on surface materials. DESIGN: Prospective study. SAMPLE POPULATION: Fecal samples from 638 hospitalized horses and 783 environmental samples. PROCEDURE: Standard bacterial culture techniques were used; the PCR test amplified a segment of the Salmonella DNA. Five disinfectants were mixed with Salmonella suspensions, and bacterial culture was performed. Swab samples were collected from 7 surface materials after inoculation of the surfaces with Salmonella Typhimurium, with or without addition of a disinfectant, and submitted for bacterial culture and PCR testing. RESULTS: Salmonella organisms were detected in fecal samples from 35 (5.5%) horses. For environmental samples, the proportion of positive bacterial culture results (1/783) was significantly less than the proportion of positive PCR test results (110/783), probably because of detection of nonviable DNA by the PCR test. Detection of Salmonella organisms varied with the surface material tested, the method of detection (bacterial culture vs PCR testing), and the presence and type of disinfectant. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the present study suggested that Salmonella organisms can be isolated from feces of hospitalized horses and a variety of environmental surfaces in a large animal hospital. Although recovery of Salmonella organisms was affected by surface material and disinfectant, bleach was the most effective disinfectant on the largest number of surfaces tested.

An outbreak of salmonellosis among horses at a veterinary teaching hospital.

Between May 1996 and February 1997, 27 horses and a veterinary student at a veterinary teaching hospital developed apparent nosocomial Salmonella Typhimurium infection. The source of the multiple-drug resistant Salmonella Typhimurium was a neonatal foal admitted for treatment of septicemia. A high infection rate (approx 13% of hospitalized horses) coupled with a high case fatality rate (44%) for the initial 18 horses affected led to a decision to close the hospital for extensive cleaning and disinfection. Despite this effort and modification of hospital policies for infection control, 9 additional horses developed nosocomial Salmonella Typhimurium infection during the 6 months after the hospital reopened. Polymerase chain reaction testing of environmental samples was useful in identifying a potential reservoir of the organism in drains in the isolation facility. Coupled with clinical data, comparison of antimicrobial resistance patterns of Salmonella Typhimurium isolates provided a rapid initial means to support or refute nosocomial infection. Although minor changes in the genome of these isolates developed over the course of the outbreak, pulsed-field gel electrophoresis testing further supported that salmonellosis was nosocomial in all 27 horses.

Field study of the safety, immunogenicity, and efficacy of an inactivated equine rotavirus vaccine.

OBJECTIVE: To determine safety, immunogenicity, and efficacy of an inactivated equine rotavirus vaccine. DESIGN: Prospective randomized controlled trial. ANIMALS: 316 pregnant Thoroughbred mares during the first year of the study and 311 during the second year. PROCEDURE: During the first year, mares received 3 doses of vaccine or placebo, IM, at 8, 9, and 10 months of gestation. Serum neutralizing antibody titers were measured before vaccination and 1 and 35 days after foaling. Antibody titers were measured in foals 1, 7, 35, 60, 90, and 120 days after birth. During the second year, mares that had been vaccinated the previous year received a single booster dose of vaccine approximately 1 month prior to parturition. Mares that had received the placebo the previous year and mares new to the study received 3 doses of vaccine or placebo. Serum neutralizing antibody titers were measured in samples taken from mares approximately 1 day after foaling and from foals approximately 1 and 60 days after birth. RESULTS: Adverse reactions were not observed. Antibody titers were significantly increased at the time of foaling and 35 days after foaling in vaccinated, compared with control, mares and for 90 days after birth in foals born to vaccinated, compared with foals born to control, mares. Incidence of rotaviral diarrhea was lower in foals born to vaccinated, compared with foals born to control, mares, but the difference was not significant. CLINICAL IMPLICATIONS: Results suggest that the equine rotavirus vaccine is safe and immunogenic and that reasonable efficacy under field conditions can be expected.

Disinfecting equine facilities.

Disinfection of equine premises provides a challenge to farm managers, in view of the variety of surfaces which may be contaminated and the wide variety of horse pathogens. Of the commonly occurring infectious diseases for which disinfection and disease control are especially important, rotavirus diarrhoea, salmonellosis and strangles are the most difficult to control. Phenolic disinfectants have been scientifically demonstrated to be effective in the presence of organic matter and are also virucidal. When used after thorough cleaning and rinsing of stall surfaces, phenolics have proved effective in controlling outbreaks of disease. In addition, 10% iodophors used for washing hands and cleaning equipment are also virucidal and bactericidal. Quaternary ammonium compounds, chlorhexidine, bleach and pine oil are readily available commercially, but are ineffective disinfectants in the presence of the organic matter encountered on horse farms.

Rotaviral diarrhea.

Rotavirus poses a challenge each foaling season to farm managers and veterinarians in intensive horse breeding areas throughout the world. By understanding the epidemiology of the disease as well as characteristics of the virus, veterinarians can make sound recommendations on prevention and control of outbreaks. Even when effective prophylactic products are developed, farm management practices, including quarantine, disinfection, and hygiene, will always need to be in force to prevent any contagious disease outbreak.

Analysis of serotypes and electropherotypes of equine rotaviruses isolated in the United States.

Equine group A rotaviruses isolated over a 10-year period in New York State, New Jersey, Kentucky, and Texas were compared serotypically and electropherotypically. All isolates were determined to be serotype 3 by reaction with hyperimmune antiserum to the serotype 3 H-2 strain of equine rotavirus. All displayed RNA electrophoretic migration patterns related to that of the H-2 strain but distinct from that of serotype 5 strain H-1. A serologic survey of 184 mares in Kentucky, which was done to determine the incidence of H-1 and H-2 infections, showed geometric mean serum neutralizing titers to the H-2 strain of equine rotavirus to be significantly higher than those to the H-1 strain. These data suggest that the serotype 3 H-2 strain is the dominant equine rotavirus in Kentucky and perhaps elsewhere in the United States. We were unable to produce confirmational evidence that the H-1 strain occurs as a natural infection in the United States.

Endoscopic Nd:YAG laser treatment of severe radiation injury of the lower gastrointestinal tract: long-term follow-up.

We report a series of patients with severe radiation injury treated with endoscopic laser photocoagulation. Eight patients with recurrent lower gastrointestinal bleeding secondary to procosigmoiditis were treated with endoscopic Nd:YAG laser therapy. Patients were followed for an average of 21.7 months after the first laser treatment. Average transfusion requirements and hospital admissions per patient-month were 0.93 and 0.27, respectively, in the prelaser period and 0.18 and 0.06, respectively, in the entire period following the first laser treatment. A total of 26 laser treatments were performed. There were three major (prolonged ileus) and one minor (pain) complication. We conclude that endoscopic Nd:YAG laser photocoagulation is a safe, effective, and lasting treatment in severe, symptomatic radiation injury of the lower gastrointestinal tract.

Prograde versus retrograde endoscopic laser therapy for the treatment of malignant esophageal obstruction: a comparison of techniques.

The prograde and retrograde approaches to the treatment of malignant esophageal obstruction with the Nd:YAG, or neodymium: yttrium, aluminum, garnet, laser are compared. With the prograde technique, tumor destruction proceeds from the proximal to the distal tumor margin. In retrograde treatment, the endoscope is passed to the distal tumor margin so that the treatment can proceed in the reverse direction, thereby completing therapy in a single treatment session. This is usually accomplished by passage of a guide wire down the biopsy channel of the endoscope, tumor dilatation, and then passage of the endoscope over the guide wire to the distal tumor margin, where laser destruction is begun. Twenty nonrandomly selected patients with malignant esophageal obstruction were studied. The first ten patients were treated with the prograde technique, the next ten with the retrograde technique. The two groups were similar with respect to age, sex, and tumor histologies. Patients treated retrogradely had narrower pretreatment lumens (average 2.3 vs. 4.1 mm) as well as longer tumor lengths (average 8.9 vs. 4.8 cm). The posttreatment luminal diameters were similar for each group: 18.0 mm for prograde; 16.3 for retrograde. In the retrograde group, therapy was completed in fewer treatments (1.6 vs. 2.9) and over a shorter period of time (3.6 vs. 7.8 days), despite the longer tumor lengths. All patients in both groups were able to tolerate a regular diet at the completion of therapy. The complication rate was low in both groups. It is felt that the retrograde technique (single session therapy) is the preferred method because it allows more-rapid treatment without increased complications and thereby shortens hospital stay and reduces hospital costs.

New laser technique for the treatment of malignant esophageal obstruction.

Endoscopic laser therapy for malignant esophageal obstruction is rapidly gaining widespread acceptance by the medical community. The standard approach utilizing the neodymium: yttrium, aluminum, garnet (Nd: YAG) laser was first described by Fleischer for squamous cell carcinoma of the esophagus and subsequently for adenocarcinoma of the gastroesophageal junction. According to his technique, treatment was begun at the proximal tumor margin and proceeded distally; as many as 13 treatments were necessary to complete therapy and relieve the obstruction. A new technique has been developed utilizing tumor dilatation so that treatment can be started at the distal tumor margin working retrogradely. This new technique has allowed treatment to be completed in a single session in most patients. This rapid completion of therapy has reduced the length of hospitalization and thereby hospital costs. It has also allowed patients to aliment earlier, thereby minimizing the metabolic consequences of prolonged intravenous feedings, has allowed patients to receive other forms of therapy on an outpatient basis, and has obviated the need for the chronic placement of tubes for drainage and feeding. The technique is described and discussed.

Preliminary report: a new technique of enterotomy closure using Nd:YAG laser welding compared to suture repair.

This study compared the histology and tensile strength of Nd:YAG laser welded and sutured small bowel enterotomies in Sprague-Dawley rats. Enterotomies (0.5 cm long) were either welded with the Nd:YAG laser (1 W and 10.6 sec pulses) or repaired with interrupted, simple 6-O silk sutures. Group I consisted of seven animals; five with enterotomies repaired by laser welding and two repaired by suturing. Group II consisted of eight animals with each having both laser and suture repairs. Animals were killed and specimens were removed and examined at 1 day, and at 1, 2, and 3 weeks postoperatively to compare the progression of healing. On macroscopic examination the laser welded enterotomies were closed 84% of the time and only 23% had adhesion formation while 90% of sutured repairs were closed and 100% had adhesion formation. Histologic examination of both suture and laser welded enterotomies demonstrated active healing at 1 week with minimal collagen bridging the enterotomies. At 2 and 3 weeks the sutured enterotomies had granulomatous reaction around the sutures while the laser welded enterotomies had minimal inflammatory response and near normal small bowel histology. The tensile strength of the 3-week specimens from both the suture and laser welded enterotomies were 50% of normal bowel. These findings suggest that the laser welding of small bowel enterotomies is comparable in closure and tensile strength to suture repair. The time required to repair the enterotomy is significantly decreased, the procedure is easily performed, and there is a marked decrease in adhesion formation following laser repair.

Biostimulation of wound healing by lasers: experimental approaches in animal models and in fibroblast cultures.

Recent evidence suggests that low-energy lasers, such as an He-Ne laser, might stimulate wound healing. In this review we are summarizing our recent observations indicating that low-energy lasers enhance collagen gene expression both in skin fibroblast cultures in vitro, as well as in animal models of wound healing in vivo.