Blood flow velocity in the common carotid artery in humans during graded exercise on a treadmill

Cerebral blood volume flow and flow velocity have been reported to increase during dynamic exercise, but whether the two increase in parallel and whether both increases occur as functions of exercise intensity remain unsettled. In this study, blood flow velocity in the common carotid artery was measured using the Doppler ultrasound method in eight healthy male students during graded treadmill exercise. The exercise consisted of stepwise progressive increases and decreases in exercise intensity. The peak intensity corresponded to approximately 85% of maximal oxygen consumption. During this exercise, the heart rate (f _c), mean blood pressure (BP) in the brachial artery and mean blood flow velocity (_cc) in the common carotid artery increased as functions of exercise intensity. At the peak exercise intensity, (f _c), BP and _cc increased by 134.5%, 20.5% and 51.8% over the control levels before exercise (P < 0.01), respectively. The resistance index (RI) and pulsatility index (PI) were determined from the velocity profile and were expected to reflect the distal cerebral blood flow resistance. The RI and PI increased during the graded exercise, but tended to decrease at the highest levels of exercise intensity. As _cc increased with increases in exercise intensity it would be expected that cerebral blood flow would also increase at these higher intensities. It is also suggested that blood flow velocity in the cerebral artery does not proportionately reflect the cerebral blood flow during dynamic exercise, since the cerebral blood flow resistance changes.     

Increased central adiposity is associated with pro-inflammatory immunoglobulin G N-glycans

Background

Increased body fat may be associated with an increased risk of developing an underlying pro-inflammatory state, thus leading to greater risk of developing certain chronic conditions. Immunoglobulin G has the ability to exert both anti- and pro-inflammatory effects, and the N-glycosylation of the fragment crystallisable portion is involved in mediating this process. Body mass index, a rudimentary yet gold standard indication for body fat, has been shown to be associated with agalactosylated immunoglobulin G N-glycans.

Anti-MOG autoantibodies in Italian multiple sclerosis patients: specificity, sensitivity and clinical association

There is considerable evidence that multiple sclerosis (MS) is an immune-mediated disease characterized by infiltration of inflammatory cells into the CNS and demyelination. Several myelin proteins may be encephalitogenic, including myelin basic protein, proteolipid protein and myelin oligodendrocyte glycoprotein (MOG), the latter being expressed on the external layer of myelin sheaths and hence accessible to antibody attack. We investigated MOG autoreactivity in serum and cerebrospinal fluid (CSF) by ELISA, employing the recombinant extracellular domain of MOG as antigen. We tested serum samples from 262 MS patients (175 relapsing-remitting, 43 primary progressive and 44 secondary progressive), 131 patients with other neurological diseases (OND) and 307 healthy controls. No patients or controls were receiving immunomodulating treatments. We found anti-MOG antibodies in the serum of 13.7% MS patients, mainly in those with secondary progressive MS (25%), in 13.7% of OND patients and in 6.2% of controls. We found a direct correlation (R(2) = 0.6, P = 0.002) between disease severity and anti-MOG titer only in patients with primary and secondary progressive MS. Anti-MOG antibodies were present in the CSF of 11.4% MS patients and 18.9% OND patients. Intrathecal synthesis of anti-MOG antibodies was demonstrated in four (4.5%) of MS patients and no OND patients. Anti-MOG antibodies are not specific for MS; however, they may characterize a subset of MS patients and this may be revealed by serial assays in relation to changing disease phase.     

Accuracy of reporting endocervical component adequacy--a continuous quality improvement project

Inaccurate reporting of the absence of an endocervical (EC) component on Pap smears often results in slide rescreens, amended reports, clinician dissatisfaction, and sometimes unnecessary repeat smears. Therefore, the accuracy of reporting EC component adequacy was selected as a quality indicator for the laboratory continuous quality improvement program (CQI). The process consisted of problem identification, analysis of the situation, collection of data, implementation of solutions, and evaluation of results. The objective of the study was to determine if the accuracy of reporting EC component adequacy on Pap smears improved after application of such a program. During the first phase, 150 Pap smears originally reported with the absence of an adequate EC component and 150 smears reported with the presence of an adequate EC component were rescreened to measure the baseline accuracy of EC component adequacy reporting. The improvement process was then implemented. A cause-and-effect diagram was developed and root cause was determined. A presentation was then made to the cytology staff. Criteria for EC component adequacy were reviewed, examples were shown, and standardized marking of EC component was implemented. Following improvement actions, a second audit of 150 Pap smears reported with the absence of an adequate EC component as well as 150 smears reported with the presence of an adequate EC component was undertaken to measure change in performance in assessing EC component adequacy. For the baseline rescreening, before initiation of the CQI program, 98% accuracy was achieved with smears that were reported as adequate for EC component present. However, the accuracy with smears reported as absence of an adequate EC component was only 71%, i.e., an adequate EC component was identified in almost 1/3 of these cases on rescreen. After the implementation of improvement actions, the accuracy with smears reported with the presence of EC component remained high (98%) and the accuracy of reporting the absence of EC component was 90%. The difference of the latter before and after the implementation was statistically significant (P = 0.015, z-test). The accuracy of reporting EC component adequacy increased following the CQI process. Using reporting EC component adequacy as an example, we demonstrate that by treating clinical problems as quality control issues and applying basic quality improvement tools, a positive outcome can be effected.     

Effect of adrenalin on inhibition of mitosis by a chalone in Ehrlich's ascites carcinoma

Department of Biology, Medico-Biological Faculty, N. I. Pirogov Second Moscow Medical Institute. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 105, No. 3, pp. 345–347, March, 1988.     

Muscle synergies involved in shifting the center of pressure while making a first step

We used the framework of the uncontrolled manifold (UCM) hypothesis to analyze multi-muscle synergies involved in making a step by a standing person. We hypothesized that leg and trunk muscles are organized into stable groups (muscle modes, M-modes) related to shifts of the center of pressure (COP) in the anterior-posterior and medio-lateral directions. Another hypothesis was that the magnitudes of the modes co-vary across repetitive trials to stabilize a certain magnitude of the COP shift in both directions. M-modes were defined using principal component analysis applied to indices of changes in the electromyographic (EMG) activity prior to releasing variable loads that were held by the subject using a pulley system. For the task of releasing the load behind the body three M-modes associated with a backward COP shift were defined. Four M-modes were defined for the task of releasing the load at the body side associated with a lateral COP shift. Multiple regression analysis was used to relate changes in the M-mode magnitudes to COP shifts. EMG changes prior to making a step were quantified over five 100 ms time windows before the lift-off of the stepping leg. Two components of the variance in the M-mode space computed across repetitions of a stepping task were quantified—a component that did not affect the average COP shift in a particular direction (variance within the UCM, V _UCM), and a component that affected the COP shift (variance orthogonal to the UCM, V _ORT). V _UCM was significantly higher than V _ORT for both directions of the COP shifts. This relation was observed for the M-modes in the stepping leg as well as in the support leg. The stepping leg showed a different time evolution of the ratio V _UCM/V _ORT such that the difference between the two variance components disappeared closer to the time of the lift-off. The findings corroborate both main hypotheses. The study supports a view that control of whole-body actions involves grouping the muscles, using fewer elemental variables to scale the muscle activity, and forming synergies in the space of the elemental variables that stabilize time profiles of important performance variables.