Subject(s)
Humans , Male , Female , Primary Health Care/methods , Primary Health Care/organization & administration , Delivery of Health Care/organization & administration , Delivery of Health Care , Personal Satisfaction , Primary Health Care/standards , Primary Health Care , Socioeconomic Factors , 24436Subject(s)
Attitude of Health Personnel , Community Health Centers/organization & administration , Patient Satisfaction , Personal Satisfaction , Primary Health Care/organization & administration , Health Care Surveys , Hospitals, University/organization & administration , Humans , Interprofessional Relations , Outpatients/psychology , Physicians, Primary Care/psychology , Seasons , Spain , Surveys and Questionnaires , Time Factors , Waiting ListsABSTRACT
A total of 237 rodents was collected in 4 regions of South Carolina from July 1994 through December 1995. Eight species were collected, including cotton mouse, hispid cotton rat, eastern woodrat, marsh rice rat, white-footed mouse, eastern harvest mouse, golden mouse, and black rat. Of the 1,514 ticks recovered from these hosts, Ixodes minor Neumann, including larvae, nymphs, and adults, was the most abundant species, representing 54% of the total. Only immature stages of other tick species were found, including larvae and nymphs of Dermacentor variabilis (Say), Amblyomma maculatum Koch, Ixodes affinis Neumann, and Ixodes scapularis Say. All 5 tick species parasitized cotton mice, cotton rats, and woodrats, which were the most important small mammal hosts for ticks at the localities studied. Rice rats were hosts of A. maculatum, D. variabilis, and L. minor. Amblyomma maculatum was more strongly associated with cotton rats than other rodent species. Ixodes scapularis was most strongly associated with cotton mice, and I. minor was more strongly associated with both woodrats and cotton mice than other species of rodents. Ixodes minor parasitized hosts in the Coastal Zone only, where among spirochete-infected hosts, it was present in significantly greater numbers than other ticks. Furthermore, I. minor was the only tick species that showed a statistically significant positive association with spirochetal infection in rodents. More I. affinis parasitized spirochete-infected hosts than I. scapularis, but fewer than I. minor. The findings discussed herein provide evidence that implicates I. minor as the possible primary enzootic vector of the Lyme disease spirochete Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt and Brenner in the Coastal Zone of South Carolina. They also indicate that the high level of B. burgdorferi infection in rodents from this region may be a function of the combined involvement of I. minor, I. affinis, and I. scapularis in the enzootic transmission of the spirochete.
Subject(s)
Lyme Disease/veterinary , Rodent Diseases/parasitology , Rodentia/parasitology , Tick Infestations/veterinary , Animals , Geography , Host-Parasite Interactions , Ixodidae , Larva , Lyme Disease/transmission , NymphABSTRACT
BACKGROUND: The purpose of this study was to asses the importance of the vascular border zone and the gray and white matter junction on the distribution of brain metastases. METHODS: We reviewed the medical records, computed tomography (CT) of magnetic resonance imaging (MRI) of 105 patients with secondary brain tumors. The metastatic lesions noted on CT scans of MRI ere matched with a predetermined standard sheet containing axial images with shading on the border zones. To be included in the border zones, the center on more than 50% of the lesion had to be situated within these zones. RESULTS: Among 100 evaluable patients, there were 302 metastatic brain lesions. Of the 302 lesions, 210 lesions were 2 cm or smaller in greatest dimension and located in the cerebral and cerebellar hemispheres. The major vascular border zones were the site of predilection for 103 lesions (62%) although the border zones constitute only 29% of the area. Gray and white matter junction was the preferred site for 135 lesions (64%). CONCLUSION: The results demonstrated that brain metastasis occurs in the vascular border zone regions and the gray and white matter junction more frequently than previously recognized, and also supported the notion that metastatic emboli tend to lodge in an area of sudden reduction of vascular caliber (gray/white matter junction) and in the area most distal vascular field (border zone).
