Cognition and brain function in elderly Tai Chi practitioners: A case-control study

Objective

To compare cognition and brain function in elderly Tai Chi and Water Aerobics practitioners.

Reduction by Cobra Venom Factor of Myocardial Necrosis after Coronary Artery Occlusion

Components of the complement system are known to play an important role in the cytolytic process and in chemotaxis of leukocytes. Cobra venom factor specifically cleaves C3 activity via activation of the alternative (properdin) complement pathway. It does not act directly on C3. If C3 is involved in tissue necrosis after ischemic injury, cobra venom factor might reduce tissue damage after acute coronary occlusion. Accordingly, in 14 control dogs occlusion of the left anterior descending artery was carried out for 24 h. Epicardial electrograms were recorded 15 min after occlusion, and 24 h later transmural specimens for creatine phosphokinase activity (CPK) and for histological analysis were obtained from the same sites. In another 14 experimental dogs, 20 U/kg cobra venom factor was given intravenously 30 min after occlusion. Serum complement levels fell within 2-4 h to <20% of normal. In the control dogs, the relationship between ST-segment elevation and CPK activity 24 h later was: log CPK = -0.06 ST + 1.48 (n = 111 specimens, 14 dogs, r = 0.77). In the experimental dogs, log CPK = -0.024 ST + 1.46 (n = 111 specimens, 14 dogs, r = 0.60), showing significantly different slopes (P < 0.001), i.e., less CPK depression for any level of ST-segment elevation. Histologically, 69 of 71 sites (97%) with ST-segment elevation exceeding 2 mV in the control dogs showed signs of necrosis 24 h later, whereas in the experimental group only 43 of 79 sites (54%) with abnormal ST-segment elevations showed signs of necrosis (P < 0.0005). At the same time, it was shown that the administration of cobra venom factor did not alter cardiac performance, collateral blood flow to the ischemic myocardium or the clotting system, but infiltration of polymorphonuclear leukocytes into the myocardium was decreased. It is concluded that cobra venom factor, by reducing the amount of C3 and C5 substrate available for chemotactic factor generation, or other as yet undefined mechanisms, protects the ischemic myocardium from undergoing necrosis, as judged by histology and local CPK activity. Hence, a new approach to limiting the extent of myocardial infarcts after experimental coronary occlusion, based upon inhibition of complement-dependent inflammatory processes, is demonstrated.     

Meditation training increases brain efficiency in an attention task

Meditation is a mental training, which involves attention and the ability to maintain focus on a particular object. In this study we have applied a specific attentional task to simply measure the performance of the participants with different levels of meditation experience, rather than evaluating meditation practice per se or task performance during meditation. Our objective was to evaluate the performance of regular meditators and non-meditators during an fMRI adapted Stroop Word-Colour Task (SWCT), which requires attention and impulse control, using a block design paradigm. We selected 20 right-handed regular meditators and 19 non-meditators matched for age, years of education and gender. Participants had to choose the colour (red, blue or green) of single words presented visually in three conditions: congruent, neutral and incongruent. Non-meditators showed greater activity than meditators in the right medial frontal, middle temporal, precentral and postcentral gyri and the lentiform nucleus during the incongruent conditions. No regions were more activated in meditators relative to non-meditators in the same comparison. Non-meditators showed an increased pattern of brain activation relative to regular meditators under the same behavioural performance level. This suggests that meditation training improves efficiency, possibly via improved sustained attention and impulse control.     

Analysis of Demographic and Educational Backgrounds of Interventional Neuroradiology Fellowship Program Director Workforce in North America

PurposeTo analyse the demographics, academic background, and scholarly activity of Interventional Neuroradiology (INR)/Endovascular Surgical Neuroradiology (ESN) program directors (PDs) in the United States (US) and Canada.MethodsA list of all INR/ESN fellowships was obtained from the Accreditation Council for Graduate Medical Education, the Committee on Advanced Subspecialty Training, maintained by Society of Neurological Surgeons, the NeuroInterventional Training list website maintained by the Society of NeuroInterventional Surgery, and the Neurosurgical Fellowship Training Program Directory website maintained by the American Association of Neurological Surgeons. Online search was performed to identify PDs for these programs. Publicly available sources used to gather information about each PD included the program websites, the HealthGrades and Doximity websites, and Elsevier's Scopus database. Demographic and educational data including age, gender, educational background, subspecialty, appointment age, interval between residency completion and appointment as PD, additional degrees, academic rank, prior leadership positions, and metrics of scholarly activity were recorded. One-way analysis of variance was used to determine differences between the means of different groups.ResultsA total of 78 PDs from 72 programs were included, of which 72 (92.3%) were male with the mean age of 49.59 years (SD 7.25). Specialty division of PDs was neurosurgery (40, 51.3%), radiology (26, 33.3%), and neurology (10, 12.8%), whereas 2 PDs were dual board-certified in neurology and radiology. Twenty-five (32.1%) PDs attended an international medical school. All PDs received an MD degree or foreign equivalent, with no PD holding a DO degree. Eleven PDs received a PhD degree and 16 PDs received fellowship from a professional medical society. The mean ± SD publications, citations, and h-indexes of PDs were 111.32 ± 121.18, 2985.0 ± 1459.0 and 22.27 ± 15.45, respectively. There was no statistical difference in scholarly activity among PDs when stratified on the basis of specialty, gender, and US region.ConclusionINR/ESN PDs are predominantly male, with a majority from neurosurgery background, and thirty percent having graduated from international medical schools.     

Selective electroencephalograph-guided microsurgical callosotomy for refractory generalized epilepsy

Between 1978 and 1985, 35 patients with medically refractory multiform seizures were submitted for sections of variable portions of the corpus callosum. Guided by intraoperative electroencephalographic and electrocorticographic monitoring, the section was carried out only in the portion of callosum that was involved in the maintenance of the bilaterally synchronous slow spike and wave discharge (as documented by intraoperative electrocorticography). In our patients, only part of the frontal corpus callosum needed to be sectioned to interrupt the bilateral synchrony of epileptic discharge. Of the 35 patients, operated on, 28 have had an adequate long-term follow up and are presented herein. All had significant improvement in seizure frequency and psychosocial functioning.     

Immunogenetic studies of juvenile dermatomyositis. III. Study of antibody to organ-specific and nuclear antigens

Ninety children with definite juvenile dermatomyositis (JDMS), who had been HLA typed, were tested for the presence of tissue or organ-specific antibodies. Sixty had active disease at the time of study. The mean disease duration was 4 years, and 30 had soft tissue calcifications. The following autoantibodies were sought: thyroid, gastric parietal cells, smooth muscle, striated muscle, microsomes, mitochondria, DNA, extractable nuclear antigen, Sm, PM-1, antinuclear antibody (ANA), and rheumatoid factor. Only the ANA and PM-1 were more frequent in patients than in controls (P less than 0.0002 and P less than 0.001, respectively). Higher levels of immune complexes (P less than 0.01) were found in sera from patients with JDMS than in sera from controls and were correlated with the presence of ANA in patients (P less than 0.01). Soft tissue calcification was not associated with any autoantibody or HLA antigen, but with disease duration and activity (P less than 0.001 and P less than 0.05, respectively). There was no association between the occurrence of any autoantibody and the presence of HLA-B8 or DR3 among the white patients with JDMS. The frequency of autoantibodies in 43 full siblings of children with JDMS was not increased. We conclude that children with JDMS, with or without HLA-B8/DR3, do not show evidence of a generalized nonspecific antibody response to tissue antigens. The significance of the increased antibody to nuclear antigens ANA and PM-1 remains to be determined.     

Factors responsible for successful HLA-DR typing of mononuclear cells from cord blood

Of 115 cord blood samples tested, both HLA-DR antigens were identified in 79% of fresh samples, 66% of older samples and 55% of freshly frozen samples. Because of weak reactions, one or two questionable antigens were present in 21% of fresh samples as compared to 34% of older samples and 45% of freshly frozen samples. Older samples showed lower cell viability, more extra reactions, and a high frequency of weak reactions. Comparison of cord blood DR antigens with parental DR antigens revealed that antigens were missed or inappropriately assigned in 5 known cases. This was more frequent with older blood samples. The critical factors in successful DR typing of cord blood samples were 1) dilution of cord blood samples with medium, 2) processing of the samples as soon as possible, and 3) overnight incubation to remove adherent cells.     

Photostimulable storage phosphor image acquisition: Evaluation of three commercially available state-of-the-art systems

Photostimulable storage phosphor (PSP) image acquisition systems have been available for several years. The technology has had the opportunity to mature; however, there has not been an independent comparison of recently marketed commercial systems. For this study, three computed radiography (CR) systems using PSP technology (Kodak CR System 400 with autoloader [Eastman Kodak, Rochester, NY], Fuji FCR AC-3CS [Fuji Medical Systems, Stamford, CT], and Agfa ADC Compact [Bayer Corp, Ridgefield Park, NJ]) were connected to an IBM RadWorks diagnostic radiology workstation (IBM Corp, White Plains NY) and evaluated for conformance to their performance specifications using guidance provided in the most recent draft acceptance testing protocol from Task Group No. 10, American Association of Physicists in Medicine. In addition, the physical requirements (eg, space and power) and connectivity to another manufacturer’s diagnostic workstation were examined. X-ray technologist comfort with each PSP imaging system and an assessment by our supporting biomedical equipment maintenance activity of their ability to service each PSP imaging system were also considered.