Locomotor Trajectories of Stroke Patients during Oriented Gait and Turning

Background

The Timed Up and Go (TUG) test is widely used to assess locomotion in patients with stroke and is considered to predict the risk of falls. The analysis of locomotor trajectories during the TUG appears pertinent in stroke patients. The aims of this study were i) to analyze locomotor trajectories in patients with stroke during the walking and turning sub-tasks of the TUG, and to compare them with healthy subjects, ii) to determine whether trajectory parameters provide additional information to that provided by the conventional measure (performance time), iii) to compare the trajectory parameters of fallers and non-fallers with stroke and of patients with right and left hemisphere stroke, and iv) to evaluate correlations between trajectory parameters and Berg Balance Scale scores.

Methods

29 patients with stroke (mean age 54.2±12.2 years, 18 men, 8 fallers) and 25 healthy subjects (mean age 51.6±8.7 years, 11 men) underwent three-dimensional analysis of the TUG. The trajectory of the center of mass was analyzed by calculation of the global trajectory length, Hausdorff distance and Dynamic Time Warping. The parameters were compared with a reference trajectory during the total task and each sub-task (Go, Turn, Return) of the TUG.

Results

Values of trajectory parameters were significantly higher for the stroke group during the total TUG and the Go and Turn sub-tasks (p<0.05). Moreover, logistic regression indicated that these parameters better discriminated stroke patients and healthy subjects than the conventional timed performance during the Go sub-task. In addition, fallers were distinguished by higher Dynamic Time Warping during the Go (p<0.05). There were no differences between patients with right and left hemisphere stroke.

Discussion and Conclusion

The trajectories of the stroke patients were longer and more deviated during the turn and the preceding phase. Trajectory parameters provided additional information to timed performance of this locomotor task. Focusing rehabilitation programs on lead-up to turn and turning could be relevant for stroke patients since the Turn was related to the balance and the phase preceding the turn seemed to distinguish fallers.     

From the inside out: Discovery of a new genus of threadsnakes based on anatomical and molecular data,with discussion of the leptotyphlopid hemipenial morphology

The systematics of Leptotyphlopidae is historically controversial mostly due to their conserved external morphology in comparison with other snakes. However, recent studies have stressed that anatomical data might be informative for clarifying the leptotyphlopid taxonomy and evolution. We erect a new genus to accommodate Leptotyphlops collaris based on evidence from osteology, hemipenial morphology, and molecular data. We also provide expanded data regarding the intraspecific variation based on additional specimens collected in field trips and literature data, performing detailed comparisons among the new genus and all other New World leptotyphlopids. The new genus is distinguished from other leptotyphlopids by its unique hemipenial morphology and its exclusive combination of osteological and external morphology characters, with molecular data also supporting the new generic arrangement. We also provide a comprehensive discussion of the hemipenial morphology for the subfamily Epictinae based on literature and novel data gathered herein.     

Role of Mood in Outcome of Biofeedback Assisted Relaxation Therapy in Insulin Dependent Diabetes Mellitus

Stressful life events and negative mood have been associated with elevated blood glucose and poor self-care in individuals with diabetes. The purpose of this controlled study was to determine the effect of mood state, specifically depression, anxiety, and daily hassles on the outcome of biofeedback assisted relaxation in insulin dependent diabetes mellitus. Eighteen subjects completed the study, nine in biofeedback assisted relaxation and nine in the control group. There were no significant group differences in blood glucose between those receiving biofeedback assisted relaxation and the subjects continuing usual care. Five of the nine experimental subjects and one of the nine control subjects were identified as succeeders according to an arbitrary criterion. Treatment failures were more depressed, more anxious, and took longer to complete the protocol than succeeders. Statistically significant correlations were found between high scores on inventories measuring depression, anxiety, and hassles intensity and higher blood glucose levels and smaller changes in blood glucose as a result of treatment. It is suggested that mood has an important impact on the response to biofeedback assisted relaxation. Further research is necessary to determine whether assessment of anxiety and depression followed by appropriate treatment where necessary should precede biofeedback assisted relaxation in insulin dependent diabetes.     

Interaction of biofeedback-assisted relaxation and diuretic in treatment of essential hypertension

Thirty patients with essential hypertension participated in a study designed to compare two treatments: diuretic medication alone (n=10) and biofeedback assisted relaxation combined with diuretic (n=20). One of 10 patients lowered BP with diuretic alone and 11 of 20 patients lowered BP with diuretic combined with biofeedback-assisted relaxation. The addition of the behavioral intervention to the diuretic therapy produced a decrease in blood pressure beyond that associated with the diuretic alone. The decreases in BP mediated by diuretic were related to high entry levels of BP, low anxiety, forehead muscle tension, anger expression and plasma renin activity. The BP decrease mediated by combined diuretic and biofeedback-assisted relaxation was associated with high pretreatment BP, anger controlled, low finger temperature and high/normal plasma renin activity.This work supported by the Northwestern Ohio Heart Association under grant No. 93132 to Dr. McGrady.     

Good news—Bad press: Applied psychophysiology in cardiovascular disorders

Dysregulation in blood pressure control can occur as a result of psychological stress in either the hypertensive or hypotensive direction. Applied psychophysiological techniques incorporating biofeedback and relaxation have been shown to be efficacious in controlled studies of hypertensive patients. Electromyograph, thermal, skin conductance and direct blood pressure feedback have been utilized alone or in combination with relaxation, blood pressure monitoring, and medication. Prediction models are proposed to define what type of hypertensive is most likely to respond with significant blood pressure decrease. Neurocardiogenic syncope is a cardiovascular disorder which manifests itself as lightheadedness, dizziness, syncope, and often migraine-type headache. Preliminary indications suggest that biofeedback-assisted relaxation may also prove beneficial to patients with this syndrome.This paper was presented as a presidential address at the 27th Annual Meeting of the Association for Applied Psychophysiology and Biofeedback, Albuquerque, NM, March, 1996. I wish to thank my present and past collaborators who contributed their thoughts and enthusiams to my program of research in applied psychophysiology of cardiovascular disorders. They are G. Argueta Bernal, Ph.D., Ilona Jurek, M.D., M. Woerner, M.Ed. R. Ph., J.T. Higgins, Jr., M.D., T. Fine, M.A. LPCC, S.W. Utz, RN, Ph.D., Gerard Roberts, M.D., Blair Grubb, M.D., Michael Weaver, RN, Ph.D.     

Testosterone and estrogen differently effect Th1 and Th2 cytokine release following trauma-haemorrhage.

The object of the study was to determine whether male and female sex steroids produce divergent effects on Th1 and Th2 cytokine release following trauma-haemorrhage. Recent studies indicate that androgens are responsible for the depressed splenocyte Th1 cytokine release in males following trauma-haemorrhage. In contrast, female mice maintain their Th1 cytokine release capacity following trauma-haemorrhage. Nonetheless, the effect of male and female sex steroids on Th1 and Th2 cytokine release following trauma-haemorrhage remains unknown. Male C3H/HeN mice were castrated and treated with pellets containing either vehicle, 5alpha-dihydrotestosterone (DHT), 17beta-estradiol (estradiol), or a combination of both steroid hormones, for 14 days prior to soft-tissue trauma (i.e. laparotomy) and haemorrhagic shock (35+/-5 mmHg for 90 min followed by adequate fluid resuscitation) or sham operation. Untreated male and female mice, as well as DHT treated female mice, served as control groups. Twenty-four hours later the animals were sacrificed, plasma obtained and splenocytes harvested. Plasma DHT and estradiol levels in treated animals were comparable with intact male and female mice, respectively. A significant depression of splenocyte Th1 cytokines, i.e. IL-2, IFN-gamma, was observed in DHT treated castrated animals, DHT treated females, and untreated males following trauma-haemorrhage, as opposed to maintained Th1 cytokine release in estradiol treated and estradiol/DHT treated castrated animals and females. The release of the anti-inflammatory cytokine IL-10 was markedly increased in DHT treated mice and males subjected to trauma-haemorrhage compared to shams, but decreased in estrogen treated mice and females under such conditions. These results suggest that male and female sex steroids differentially affect the release of Th1 and Th2 cytokines following trauma-haemorrhage and should be further studied for their potential to modulate splenocyte function in trauma victims.     

17 beta-Estradiol normalizes immune responses in ovariectomized females after trauma-hemorrhage

Recent studies indicate that immuneresponses in proestrus females are maintained after trauma-hemorrhagebut markedly depressed in ovariectomized females under such conditions.The current study tested the hypothesis that the decreased estrogenlevels after ovariectomy are responsible for this immune depression. Tostudy this hypothesis, ovariectomized female CBA/J mice were subjected to laparotomy (i.e., soft tissue trauma) and hemorrhagic shock (35 ± 5 mmHg for 90 min, then resuscitated) or sham operation. The micereceived either 17-estradiol (E2; 100 µg/25 g body wt) or vehiclesubcutaneously during resuscitation. Immune cells were isolated 24 h thereafter. Splenocyte proliferation and interferon-, interleukin(IL)-2, and IL-3 release were significantly depressed aftertrauma-hemorrhage in vehicle-treated mice, whereas these functions weremaintained in E2-treated mice. Peritoneal macrophage IL-1 and IL-6release and splenic macrophage IL-6 and IL-12 release were alsosignificantly depressed in vehicle-treated mice after trauma-hemorrhage, and release of these cytokines was restored by E2treatment. In summary our findings indicate that the depressed splenicand peritoneal immune responses after trauma-hemorrhage can benormalized by a single dose of E2. Thus estrogen appears to be thecausative factor in the maintenance of immunocompetence in femalesafter trauma-hemorrhage, and its administration to ovariectomized orpostmenopausal females should be helpful in preventing immunedepression under such conditions.

     

Leukocyte Attraction by CCL20 and Its Receptor CCR6 in Humans and Mice with Pneumococcal Meningitis

We previously identified CCL20 as an early chemokine in the cerebrospinal fluid (CSF) of patients with pneumococcal meningitis but its functional relevance was unknown. Here we studied the role of CCL20 and its receptor CCR6 in pneumococcal meningitis. In a prospective nationwide study, CCL20 levels were significantly elevated in the CSF of patients with pneumococcal meningitis and correlated with CSF leukocyte counts. CCR6-deficient mice with pneumococcal meningitis and WT mice with pneumococcal meningitis treated with anti-CCL20 antibodies both had reduced CSF white blood cell counts. The reduction in CSF pleocytosis was also accompanied by an increase in brain bacterial titers. Additional in vitro experiments showed direct chemoattractant activity of CCL20 for granulocytes. In summary, our results identify the CCL20-CCR6 axis as an essential component of the innate immune defense against pneumococcal meningitis, controlling granulocyte recruitment.     

L-Arginine restores splenocyte functions after trauma and hemorrhage potentially by improving splenic blood flow

Several studiesindicate that immune responses are markedly depressed early after onsetof hemorrhage. Decreased organ blood flow has been implicated in thepathophysiology of altered immune responses after trauma-hemorrhage. Inthis regard, administration ofL-arginine has been shown torestore depressed intestinal and hepatic blood flow aftertrauma-hemorrhage, probably due to provision of substrate forconstitutive nitric oxide synthase (cNOS). It remains unknown, however,whether administration ofL-arginine also amelioratesdepressed splenic blood flow and whether this agent has any salutaryeffects on depressed splenocyte functions after trauma-hemorrhage. Malerats underwent sham operation or laparotomy and were bled to andmaintained at a mean arterial blood pressure of 40 mmHg until 40% ofmaximum shed blood volume (MBV) was returned as Ringer lactate (RL).Hemorrhaged rats were then resuscitated with RL (4 times MBV over 1 h).During resuscitation, rats received 300 mg/kgL-arginine or saline (vehicle)intravenously; 4 h later, splenic blood flow, splenocyte proliferation,and splenocyte interleukin (IL)-2 and IL-3 were determined.Administration of L-arginineimproved depressed splenic blood flow and restored depressed splenocytefunctions after trauma-hemorrhage. Therefore, provision ofL-arginine during resuscitationafter trauma-hemorrhage should be considered a novel and safe approachfor improving splenic organ blood flow and depressed splenocytefunctions under such conditions.