ABSTRACT
Ubiquitous reduction of the gap junction protein Connexin43 (Cx43) in mice provides beneficial effects on progression and composition of atherosclerotic lesions. Cx43 is expressed in multiple atheroma-associated cells but its function in each cell type is not known. To examine specifically the role of Cx43 in immune cells, we have lethally irradiated low-density lipoprotein receptor-deficient mice and reconstituted with Cx43+/+, Cx43+/- or Cx43-/- haematopoietic fetal liver cells. Progression of atherosclerosis was significantly lower in aortic roots of Cx43+/- chimeras compared with Cx43+/+ and Cx43-/- chimeras, and their plaques contained significantly less neutrophils. The relative proportion of circulating leukocytes was similar between the three groups. Interestingly, the chemoattraction of neutrophils, which did not express Cx43, was reduced in response to supernatant secreted by Cx43+/- macrophages in comparison with the ones of Cx43+/+ and Cx43-/- macrophages. Cx43+/- macrophages did not differ from Cx43+/+ and Cx43-/- macrophages in terms of M1/M2 polarisation but show modified gene expression for a variety chemokines and complement components. In conclusion, titration of Cx43 expression in bone marrow-derived macrophages reduces atherosclerotic plaque formation and chemoattraction of neutrophils to the lesions.
Subject(s)
Aorta/metabolism , Aortic Diseases/prevention & control , Atherosclerosis/prevention & control , Connexin 43/metabolism , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/metabolism , Animals , Aorta/pathology , Aortic Diseases/genetics , Aortic Diseases/immunology , Aortic Diseases/metabolism , Aortic Diseases/pathology , Atherosclerosis/genetics , Atherosclerosis/immunology , Atherosclerosis/metabolism , Atherosclerosis/pathology , Cells, Cultured , Chemotaxis, Leukocyte , Coculture Techniques , Connexin 43/deficiency , Connexin 43/genetics , Disease Models, Animal , Macrophages/immunology , Macrophages/metabolism , Mice, Inbred C57BL , Mice, Knockout , Neutrophil Infiltration , Phenotype , Plaque, Atherosclerotic , RNA Interference , Receptors, LDL/deficiency , Receptors, LDL/genetics , Transfection , Whole-Body IrradiationABSTRACT
STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To describe the characteristics of patients with work-related traumatic spinal cord injuries (TSCI) in Chile. SETTING: Hospital del Trabajador in Santiago, Santiago, Chile. METHODS: Patients suffering from TSCI incurred at the workplace from 1986 to 2005 were identified through records of the Asociación Chilena de Seguridad (ACHS, Chilean Safety Association). RESULTS: The medical records of 173 patients, 172 men and 1 woman, were analyzed. The yearly average incidence was 7.8 per million workers. Age at TSCI onset was 38.2 ± 12.1 years. The principal external causes for TSCI incurred at the workplace were falls from a height in 86 cases (49.7%) and trauma blows to the vertebral spine in 61 cases (35.3 %). More falls occurred in the field construction, and other traumas occurred as a result of traumatic blows caused by tree trunks and stones in forestry and mining sectors. Mortality in this series was 8.7%, and the worst prognosis was for older patients with complete tetraplegia. The paraplegia:tetraplegia ratio was 3.2:1. CONCLUSIONS: The characteristics of workplace TSCI are specific to this population. It is important therefore to develop prevention programs for specific work-related TSCI.
Subject(s)
Occupational Diseases/epidemiology , Spinal Cord Injuries/epidemiology , Wounds and Injuries/epidemiology , Accidental Falls/mortality , Adolescent , Adult , Aged , Chile/epidemiology , Cohort Studies , Female , Forestry , Humans , Incidence , Male , Middle Aged , Mining , Retrospective Studies , Spinal Injuries/complications , Spinal Injuries/epidemiology , Young AdultABSTRACT
STUDY DESIGN: Descriptive case series study. OBJECTIVE: To describe the course of five spinal cord injury (SCI) patients who underwent proximal amputation of the inferior extremity, secondary to recurrent, complicated pressure ulcers (PU) and the clinical impact this intervention had in these patients. PLACE: Trabajador Hospital in Santiago, Chile. METHOD: Revision of five clinical cases of patients who underwent partial hemipelvectomy or hip disarticulation with amputation of the extremity as treatment for pelvic recurrent PU with chronic secondary osteomyelitis. The clinical impact was quantified as days of hospital stay, number of surgeries and previous and post surgery PU. RESULTS: After the proximal amputation of the extremity, patients significantly decreased number of days of hospital stay (P=0.035), number of surgeries (P=0.015) and PU (P=0.0065). CONCLUSION: Partial hemipelvectomy and hip disarticulation with proximal amputation of the inferior extremity are rescue procedures that can be last resource treatment for chronic recurrent pelvic PU secondary to chronic osteomyelitis.
