Ventral Abdominal Approach for Laparoscopic Cryptorchidectomy in Horses

Objective —To report a ventral abdominal approach and a ligating loop technique for laparoscopic cryptorchidectomy in horses.
Study Design —Prospective.
Sample Population—Six horses, aged 1 to 5 years, with retained testes.
Methods —One laparoscopic portal and three to four instrument portals were used for ventral abdominal laparoscopic cryptorchidectomy. Laparoscopic instruments were used to maneuver and secure the testis through a ligating loop (modified Roeder knot) that was secured from outside the abdominal cavity. Only minimal enlargement of one instrument portal was used to remove the testicle.
Results —Three horses were bilateral cryptorchids, and three were unilateral (left side, two; right side, one) cryptorchids. Operative time, defined as the time from laparoscope insertion to removal, ranged from 20 to 25 minutes for unilateral cryptorchids and from 40 to 50 minutes for bilateral cryptorchids.
Conclusions —The reported technique allowed decreased tension on the tissues during ligation and removal of the testis from the peritoneal cavity. Improved observation of the abdominal cavity, ligation security, shortened patient confinement time, and minimally invasive technique are all considered to be benefits of laparoscopic cryptorchidectomy.
Clinical Relevance —Direct observation of retained testes and intraabdominal castration are distinct advantages of the use of laparoscopy in horses that have had previous unsuccessful surgical attempts, horses with unknown histories that have retained testicular tissue, or bilateral abdominal cryptorchids.     

Acceleration of Second and Fourth Metatarsal Fracture Healing with Recombinant Human Bone Morphogenetic Protein‐2/Calcium Phosphate Cement in Horses

Objective— To compare the efficacy of recombinant human bone morphogenetic protein‐2 (rhBMP‐2)/calcium phosphate (CP) to autogenous cancellous bone graft (CBG) and to no treatment on bone healing, in surgically induced osteotomies and ostectomies of the accessory metatarsal bones in an equine model. Study Design— Experimental. Animals— Adult horses (n=9). Methods— Segmental ostectomies of the second metatarsal bone (MT2) and osteotomies of the fourth metatarsal bone (MT4) were performed bilaterally in 9 horses. There were a total of 35 defects (1 MT4 was previously fractured) created and supplemented randomly either with no treatment (untreated control), rhBMP‐2/CP cement, or matrix (CPC or CPM), or CBG. Radiography was performed every 2 weeks until study endpoint at 12 weeks. After euthanasia, bone healing was evaluated using radiography, mechanical testing, and histology. Data were analyzed with ANOVA followed by the Duncan's Multiple Range Test or nonparametric analyses. Results— At 12 weeks, radiographic scores for union were significantly greater for the rhBMP‐2 (P<.0001) and CBG (P=.004) groups compared with the untreated control group, for both MT2 ostectomies and MT4 osteotomies. The rhBMP‐2 treated MT2 had greater maximum torque to failure in torsion than CBG and control limbs at 12 weeks (P=.011). Histologic analysis demonstrated increased bone formation and more mature bone at the ostectomy site for MT2 in the rhBMP‐2 and CBG groups compared with the untreated control group. Conclusion— Injection of rhBMP‐2/CP into surgically induced ostectomies and osteotomies of the accessory metatarsal bones might accelerate early bone healing in the horse. Clinical Relevance— RhBMP‐2/CP may be as effective if not superior to CBG as an adjuvant treatment to accelerate healing of bone defects.     

Does a Rising Tide Lift All Metropolitan Boats? Assessing Poverty Dynamics by Metropolitan Size and County Type

ABSTRACT This paper examines the relationship between U.S. metropolitan county employment growth and poverty. Differential job growth–poverty linkages are found across metropolitan size and type of county. Own‐county employment growth significantly reduces central‐county poverty in large metropolitan areas relative to suburban county poverty. Compared with larger metropolitan areas, broader metropolitan‐wide job growth has more poverty reducing benefits in medium and smaller metropolitan areas, suggesting fewer metropolitan‐wide job‐accessibility constraints. The results suggest that targeted place‐based efforts to spur job growth may help reduce poverty.     

Low‐Income Dynamics in Canadian Communities: A Place‐Based Approach

ABSTRACT Canadian poverty rates have persisted at disappointingly high levels despite almost 15 years of continuous economic growth. The problem is exacerbated by some communities and neighborhoods having exceedingly high poverty, including very high rates for vulnerable demographic groups, such as aboriginals and recent immigrants. We investigate low‐income rates (poverty rates) for 2,400 Canadian “communities” over the 1981–2001 period. By focusing on communities, we fill a void in the related Canadian literature, which tends to focus on individuals, case studies, or more aggregate measures, such as provinces. Our approach allows us to assess the role of place‐based policies. Particular attention is given to communities with differing shares of aboriginal Canadians and recent immigrants. One novel feature is our analysis of both “short‐term” and “long‐term” causes of differential community poverty rates. The results suggest that community low‐income rates are more affected by initial economic conditions in the short term, with certain demographic factors becoming relatively more important in the long run.     

DETECTION OF PNEUMOTHORAX AND PLEURAL EFFUSION WITH HORIZONTAL BEAM RADIOGRAPHY

Forty‐seven patients with a known history of thoracic trauma or clinical suspicion of pneumothorax were selected for thoracic imaging. The patient population was composed of 42 dogs and five cats. Standard vertical beam (VB) left and right lateral and ventrodorsal/dorsoventral (VD/DV) projections were obtained for each patient, and at least one horizontal beam (HB) projection (VD projection made in lateral recumbency). A total of 240 images were reviewed. Subjective assessment for the presence and degree of pneumothorax and pleural effusion was made more confidently with HB projections. Pneumothorax was identified in at least one projection in 26 patients (26 dogs) and pleural effusion in 21 patients (19 dogs and two cats). Pneumothorax and pleural effusion were present concurrently in 17 dogs. Pneumothorax and pleural effusion were graded for each image as absent, mild, moderate, or severe. Right (P<0.001) and left (P<0.05) lateral HB VD projections and the standard VB left lateral projection (P<0.05) were significantly more likely to detect and grade pneumothorax severely than the VB VD/DV views. The right lateral HB projection had the highest rate of detection and gradation of severity for pneumothorax compared with other views. VD/DV projections had the lowest sensitivity for detection of the pneumothorax and gradation of severity for pneumothorax and pleural effusion. No significant difference in diagnosis (P=0.9149) and grade (P=0.7757) of pleural effusion were seen between views, although the left lateral HB had both the highest rate of detection and grade of severity.     

Exporting,Foreign Direct Investment,and Wages: Evidence from the Canadian Manufacturing Sector

Do exporters and foreign‐controlled establishments pay their workers higher wages than non‐exporters and domestic‐controlled establishments? This paper draws on an employer–employee data set to explore the existence of exporter and foreign‐owned wage premiums in the Canadian manufacturing sector. Results from wage regression models reveal that, on the whole, exporters and foreign‐controlled plants do pay higher wages than non‐exporters and domestic‐controlled plants. These results hold even after controlling for other plant and worker characteristics, although the wage differentials are substantially smaller. Furthermore, while the impact of foreign ownership on wages is found to be widespread across industries and regions, that of exporting is not. At the industry level, the wage effects of export‐market participation are strongest for workers in plants belonging to scale‐based industries; regionally, they are strongest in Quebec and British Columbia.