Three‐dimensional morphometry of the A2 segment of the anterior cerebral artery with neurosurgical relevance

Most prior morphometry data regarding the A2 segment of the anterior cerebral artery (ACA) have been based on cadaveric measurements. With newer imaging modalities, surgical techniques, and minimally invasive procedures, new standards for the anatomy of this vessel are necessary. A novel computer‐based data system was used to analyze the three‐dimensional (3D) morphometry of 230 A2 segments. In addition, tortuosity (TI) and deviation indices (DI) for this segment were calculated. The mean internal diameter of the A2 segment was 1.86 mm, and segments tended to be larger in men and on left sides. A2 segments were asymmetrical in 43%, and this was more common in women. Lengths tended to be greater on right sides and in men. Volumes were greater in men and increased with age, which was statistically significant. These gender differences were found to be statistically significant (P < 0.05), for both volume and diameter. TI was equal among sides, but DI was more often greater on right sides. The correlation coefficient ratio for length and DI was statistically significant. It is important to understand various 3D morphometrical differences particularly between genders. By constructing blood flow simulation models and during revascularization procedures, surgeons are able to gain a better understanding of each patient's vascular anatomy. These additional 3D data regarding the anatomy of the postcommunicating parts of the ACA may be useful to the neurosurgeon and interventional neuroradiologist. These data may assist with an earlier diagnosis of pathologies affecting the 3D morphology of the ACA. Clin. Anat. 23:759–769, 2010. © 2010 Wiley‐Liss, Inc.     

The cost and appropriateness of health care technology in South Africa. A plea for the development of a local medical equipment industry

Some of the main reasons for the increase in the cost of health care technology are summarized. Local problems in the health care delivery system are not being solved effectively by imported medical equipment. The expertise required for the local solution of problems is available in the RSA and should be developed further. A private-sector consortium with matching funding from the State should serve as a clearing house for developing and evaluating assessment criteria, promoting the use of existing cost-efficient medical technologies, and identifying obsolete and inappropriate ones. The formation of a local health care technology corporation should be considered seriously.     

Potent enhancement of [3H]nitrendipine binding in rat cerebral cortical and cardiac homogenates: a putative mechanism for the action of MDL 12,330A

[3H]Nitrendipine [( 3H]NTD), a specific high-affinity calcium channel antagonist, was used to label dihydropyridine binding sites associated with calcium channels in rat cerebral cortical and cardiac homogenates. A novel lactamimide compound, MDL 12,330A, has been shown previously to have negative inotropic and chronotropic effects in isolated working guinea-pig hearts and these effects are reversed by the administration of calcium. MDL 12,330A is potent in enhancing [3H]NTD binding in membranes prepared from the cerebral cortex and the heart, with EC50 values of 6.1 X 10(-8) and 3.4 X 10(-8) M, respectively, at 37 degrees C. This allosteric effect by MDL 12,330A is similar to that produced by a known calcium channel antagonist, d-cis diltiazem, which has been shown previously to enhance [3H]NTD binding at 37 degrees C. The extent of enhancement by MDL 12,330A depends on incubation temperature (37 degrees C greater than 25 degrees C greater than 0 degrees C). The mechanism of this enhancement by MDL 12,330A is due to a decrease in the dissociation rate constant of the dihydropyridine-calcium channel supramolecular complex. MDL 12,330A is the most potent drug thus far examined which demonstrates the enhancement of [3H]NTD binding.     

Real-time three-dimensional echocardiography: still a research tool or an imaging technique ready for daily routine practice? A pilot feasibility study in a tertiary cardiology centre

BACKGROUND: The majority of studies demonstrating the diagnostic potential of three-dimensional (3D) echocardiography have been conducted on selected series of patients in research laboratories. AIM: To investigate the feasibility and usefulness of real-time 3D transthoracic echocardiography (RT 3D TTE) in daily routine practice. METHODS: The study group consisted of 35 consecutive patients referred to our echocardiographic laboratory. All subjects underwent standard 2D TTE and RT 3D TTE with the use of a commercially available ultrasound system (Sonos 7500, Philips Medical Systems). The quality of 3D acquisitions and post-processed images was graded as: insufficient, satisfactory, good or demo. RESULTS: 3D TTE of the study group yielded 298 acquisitions. 87,2% of acquisitions required post-processing. The quality of 3D datasets was graded as insufficient in 8,0%, satisfactory in 31,4%, good in 37,2% and demo in 23,4% of all acquisitions and reconstructions. Mean time required for 3D TTE, including post-processing, was 12 minutes. 3D reconstructions were particularly helpful in patients with valvular disease or prostheses (n=13), enabling detailed qualitative analysis of leaflets morphology and mobility. In cases of mitral valve prolapse (n=4) 3D TTE allowed identification of the prolapsing scallops. 3D color Doppler flow mapping enabled complete visualization of the regurgitant jets. "En face" reconstructions of atrial septal defects (n=2) facilitated assessment of the morphology of the defects and the tissue rims. In patients with cardiac pacemaker (n=4) 3D TTE allowed excellent visualization of the ventricular lead along with its tip. In patients with ischemic heart disease (n=14) 3D TTE failed to provide additional, clinically relevant information. CONCLUSIONS: RT 3D TTE may be used in clinical settings with high feasibility rate and provides additional, clinically relevant qualitative information. The lack of on-board quantitative analysis tools is the main limitation of the currently available system.     

Application of cellular biosensors for analysis of bioactivity associated with airborne particulate matter

Exposure to airborne particulate matter (PM) is a known risk factor for adverse health effects observed in many environmental and occupational settings. The pathological mechanisms involved in PM-mediated toxicity depend on the size and contents of particles that vary depending on the source of emission. Chemical compositions of PM show multiple components with different bioavailabilities that are capable of acting on multiple molecular and cellular targets, making it difficult to predict PM-associated toxicity based solely on chemical analysis. The aim of the study was to develop robust, sensitive and economical assays for environmental pollutants based on genetically modified mammalian cells. We tested the suitability of two biosensor assays, Fluorescent Cell Chip and Oxibios, developed in part in our laboratories, for assessment of the potential toxicity of airborne PM. Reference PM and PM obtained by sampling of diesel exhaust and indoor air in aluminum and copper facilities in Poland were tested with the two bioassays using unified experimental protocols. Resultant data showed complex patterns of stimulatory and inhibitory activities that were consistent with the origin of PM and might be correlated with their chemical composition. The analysis was informative with regard to type and extent of possible toxicity associated with specific PM and allowed for detection of significant differences between PM from different industrial sites and particular locations within the same industrial sites as well as overall ranking of toxicity risk based on chemical analysis.     

Allogeneic Haematopoietic Stem Cell Transplantation as Therapy for Chronic Granulomatous Disease��Single Centre Experience

Chronic granulomatous disease (CGD) is phagocytic cell metabolic disorder resulting in recurrent infections and granuloma formation. This paper reports the favourable outcome of allogeneic transplantation in six high-risk CGD patients. The following donors were used: HLA-matched, related (two) and unrelated (three), and HLA-mismatched, unrelated (one). One patient was transplanted twice using the same sibling donor because of graft rejection at 6 months after reduced-intensity conditioning transplant (fludarabine and melphalan). Myeloablative conditioning regimen consisted of busulphan and cyclophosphamide. Stem cell source was unmanipulated bone marrow containing: 5.2 (2.6-6.5) × 10(8) nucleated cells, 3.8 (2.0-8.0) × 10(6) CD34+ cells and 45 (27-64) × 10(6) CD3+ cells per kilogramme. Graft-versus-host disease prophylaxis consisted of cyclosporine A and, for unrelated donors, short course of methotrexate and anti-T-lymphocyte globulin. Mean neutrophile and platelet engraftments were observed at day 22 (20-23) and day 20 (16-29), respectively. Pre-existing infections and inflammatory granulomas resolved. With the follow-up of 4-35 months (mean, 20 months), all patients are alive and well with full donor chimerism and normalized superoxide production.