Early events in the life cycle of JC virus as potential therapeutic targets for the treatment of progressive multifocal leukoencephalopathy

The human polyomavirus, JC virus (JCV), is the etiological agent of progressive multifocal leukoencephalopathy (PML). PML occurs almost exclusively in the setting of severe and prolonged immunosuppression and it remains an important and life-threatening complication in the acquired immunodeficiency syndrome (AIDS) population. Several drugs that target DNA replication have shown efficacy at inhibiting JCV replication in vitro but none to date have shown in vivo efficacy. The authors' laboratory has been studying early events that contribute to infection of susceptible cells by JCV. They previously demonstrated that infection of glial cells by JCV requires clathrin-dependent endocytosis and that this early step in the viral life cycle can be blocked by the antipsychotic drug, chlorpromazine. As chlorpromazine is associated with the development of extrapyramidal symptoms that may be heightened in AIDS patients, the authors sought to test the atypical antipsychotic, clozapine, for antiviral activity against JCV. In this report, the authors show that clozapine is as effective as chlorpromazine at inhibiting infection. They further demonstrate that low-dose combinations of both drugs synergistically inhibit infection.

Gender-specific response to interstitial angiotensin II in human white adipose tissue

Angiotensin II is synthesized locally in various tissues. However, the role of interstitial angiotensin II in the regulation of regional metabolism and tissue perfusion has not as yet been clearly defined. We characterized the effect of interstially applied angiotensin II in abdominal subcutaneous adipose tissue of young, normal-weight, healthy men (n = 8) and women (n = 6) using the microdialysis technique. Adipose tissue was perfused with 0.01, 0.1, and 1 micro M angiotensin II. Dialysate concentrations of ethanol, glycerol, glucose, and lactate were measured to assess changes in blood flow (ethanol dilution technique), lipolysis, and glycolysis, respectively. Baseline ethanol ratio and dialysate lactate were both significantly higher, whereas dialysate glucose was significantly lower in men vs. women. In men, ethanol ratio and dialysate glucose, lactate and glycerol did not change significantly during perfusion with angiotensin II. In women, however, angiotensin II induced a significant increase in ethanol ratio and dialysate lactate and a decrease in dialysate glucose close to values found for men and this response was almost maximal at the lowest angiotensin II concentration used. Dialysate glycerol did not change significantly. We conclude that baseline blood flow and glucose supply and metabolism is significantly higher in women than in men. In men, interstitial Ang II has only a minimal effect on adipose tissue blood flow and metabolism. In women, however, a high physiological concentration of interstitial angiotensin II can reduce blood flow down to values found in men. This is associated with an impaired glucose supply and metabolism. Additionally, Ang II inhibits lipolysis.

[Effective "home remedies" in orthostatic hypotension. A glass of water before getting up and a brick under the bed]

The symptoms of orthostatic hypotension can be considerably improved by non-pharmacological treatment, and patients with such symptoms should not initially be given medication. Many patients, for example, show a pronounced increase in blood pressure shortly after drinking water, and this phenomenon can be utilized to ameliorate symptoms. In patients who respond inadequately, treatment with pharmacological agents is indicated. The most appropriate drug needs to be selected individually on the basis of its action and tolerability. All medications suitable for treating orthostatic hypotension can appreciably increase the blood pressure in the prone patient.

[Relationship, resistance and insight as depicted in measures concerning form and content of speech - a textual analysis of the course of a female in-patient with eating disorder]

OBJECTIVES

This multi-methodical single case study examines how relationship, resistance and insight, the important therapeutic factors, are conveyed in a therapeutic process.

METHODS

For depicting interaction the textual parameters - direct speech, acknowledgement tokens, activity of speech and personal pronouns - of Formal Psycholinguistic Text Analysis (Overbeck et al., 1996) are applied. The activity of the unconscious theme is measured by the Interferenzindex (Argelander, 1984). The link of emotional experiences with words is depicted by the Computerized Referential Activity method (Mergenthaler and Bucci, 1999). The attainment of emotional insight in the Model of the Therapeutic Cycle is perceived via the Emotion-/Abstraction-Patterns (Mergenthaler, 1997).

RESULTS

Three phases are discriminated accordingly: Resistance, characterised by defensive intellectualization, symbolic representation on the basis of the secure relationship and emotional insight and detachment.

CONCLUSIONS

The validity of the results in this single case study is guaranteed by the multi-methodical strategy.

Limited effect of systemic beta-blockade on sympathetic outflow

Central beta-adrenoreceptors may augment sympathetic outflow. We tested the hypothesis that beta-blockade attenuates central sympathetic outflow by inhibiting central adrenoreceptors. We studied 18 healthy controls (4 female, 14 male; age, 26+/-6 years, body mass index, 23+/-3 kg/m(2)). ECG, brachial, and finger arterial blood pressure, muscle sympathetic nerve activity, and respiration were measured continuously before and during complete beta-blockade. Subjects received a total intravenous dose of 0.21 mg/kg of propranolol in 15 minutes. Spontaneous baroreflex slopes were calculated using the sequence technique (BRSup, BRSdown). The sympathetic baroreflex slope was determined at baseline using phenylephrine and sodium nitroprusside infusions. The subjects underwent cold pressor testing before and during beta-blockade. The R-R interval increased from 861+/-119 ms at baseline to 952+/-141 ms during beta-blockade (P<0.01). Blood pressure was 117+/-9/65+/-8 mm Hg at baseline and 117+/-10/67+/-8 mm Hg during beta-Blockade (P=NS). beta-Blockade did not affect baroreflex sensitivity (BRSup: 21+/-10 versus 28+/-11 ms/mmHg, P<0.1; BRSdown: 17+/-8 versus 20+/-8 ms/mmHg, P=NS). Muscle sympathetic nerve activity increased significantly during beta-blockade (number of bursts/100 beats: 32+/-9 versus 40+/-14, P<0.05), compared with baseline. However, the operating points of the parasympathetic and sympathetic baroreflex during beta-blockade were on the baroreflex curves obtained at baseline. beta-Blockade blunted the heart rate response to cold pressor testing; blood pressure and muscle sympathetic nerve activity responses were similar. Our study demonstrates that propranolol does not cause an acute decrease in sympathetic activity in normotensive young subjects. This, observation is not consistent with an important tonic stimulatory effect of beta-adrenoreceptors in the brain.

Altered autonomic support of arterial blood pressure with age in healthy men

BACKGROUND

Primary aging is associated with changes in the autonomic nervous system (ANS), but the functional significance of these changes for systemic circulatory control of arterial blood pressure (BP) is unknown. We tested the hypothesis that ANS support of BP is altered in healthy older humans.

METHODS AND RESULTS

A total of 23 young (aged 24+/-1 years; systolic/diastolic BP, 126+/-2/66+/-1 mm Hg) and 16 older (aged 65+/-1 years; systolic/diastolic BP, 125+/-3/62+/-2 mm Hg) healthy men were studied before and during ganglionic blockade (intravenous trimethaphan). The reduction in mean BP (radial artery catheter) with trimethaphan was almost twice as great in the older men (-33+/-2 versus -19+/-2 mm Hg; -40% versus -22% of baseline; P<0.01) due to a lack of increase in heart rate (3+/-2 versus 25+/-2 bpm; P<0.001) and cardiac output (-0.42+/-0.19 versus 1.01+/-0.26 L/min; P<0.001); the decreases in systemic vascular resistance were not different. The absence of tachycardia in the older men was associated with reduced baseline heart rate variability (HRV, P<0.05); the change in heart rate with trimethaphan correlated with the standard deviation of the R-R intervals (HRV(SD R-R interval); r=0.57, P<0.001). Among individual subjects (pooled groups), the reductions in mean BP with trimethaphan were most strongly related to measures of sympathetic activity (r=0.58 to 0.67, P<0.005), change in mean BP with intravenous phenylephrine (r=0.57, P<0.001), and HRV(SD R-R interval) (r=-0.40, P<0.01).

CONCLUSIONS

ANS support of BP is altered with age in healthy men due to less cardiac vagal inhibition of heart rate and cardiac output. Basal sympathetic activity and alpha-adrenergic vascular sensitivity are also key physiological correlates of ANS support of BP in healthy men.

Autonomic nervous system function in patients with monogenic hypertension and brachydactyly: a field study in north-eastern Turkey

Laboratory studies in patients with autosomal-dominant hypertension and brachydactyly showed increased sensitivity to sympathetic stimuli and severe abnormalities in baroreflex buffering. To further elucidate the mechanisms by which impaired baroreflex sensitivity could influence blood pressure (BP), we conducted autonomic testing under field conditions. We studied 17 hypertensive affected (13 to 48 years, BMI 22.7 +/- 6.5 kg/m(2), 160 +/- 23/98 +/- 15 mm Hg) and 12 normotensive non-affected (9 to 60 years, BMI 24.0 +/- 4.7 kg/m(2), 120 +/- 16/70 +/- 10 mm Hg) family members. Pulse intervals and finger BP were measured using the Portapres device. Valsalva ratio, the blood pressure overshoot during phase IV of the Valsalva manoeuver, the Ewing coefficient (RR30/15 ratio), and heart rate and BP variability were similar in affected and non-affected family members. Overall, baroreflex sensitivity calculated using the cross-spectral (BRSLF, BRSHF) and sequence techniques (BRS+, BRS-) was not different between the groups. However, in younger family members, BRS+ was 12 +/- 3.7 and 22 +/- 13 msec/mm Hg in affected and in non-affected family members, respectively. The decline in BRS with age and with increasing blood pressure was absent in affected family members. We conclude that autonomic reflex testing conducted under field conditions is not impaired in patients with monogenic hypertension and brachydactyly. However, noninvasive testing showed impaired baroreflex control of heart rate at a young age. The reduced BRS in young family members with moderate arterial hypertension may suggest that the impaired baroreflex function is not secondary to the hypertension but rather a primary abnormality, which aggravates the progression of hypertension.

[Psychocardiology today]

DEFINITION

The term "cardiopsychology" contains the scientific knowledge with regard to psychosocial factors of the emergence, the course, the rehabilitation and the illness processing (coping) of cardiac diseases.

STUDIES

Probably there is no psychosocial topic with so many presumably methodically high standing (namely representative prospective and controlled) long-term studies and so many reviews or metaanalyses as we have for cardiac diseases, particularly the coronary heart disease. The knowledge on cardiopsychology is extensive, incoherent and contradictory and in so far incalculable. A group of 38 international scientists came together 1998 and founded the "Status and Consensus Conference Cardiopsychology". The objective of the project is to systematize and evaluate the scientific knowledge about psychosocial factors affecting the etiology, development, rehabilitation of and coping with coronary heart diseases worldwide. The systematic reviews on the above mentioned subjects are intensively discussed and evaluated by all scientists involved in the status conferences. The reviews are finally published only after several revisions leading to a concurring consensus. This working process guarantees an extraordinary high standard of all resulting reviews. Thus the Public Health can be provided with a systematic knowledge basis. The reviews resulting from the status conferences are published as a special series in the publishing house Verlag für Akademische Schriften in Frankfurt, Germany. Besides all essentials are opened for the public and can be visited in the Internet: http://www.psychokardiologie.de.

PSYCHOSOCIAL KNOWLEDGE

The essay on hand gives a short historical summary of this field of research and then discusses the psychosocial research to the risk factor model. After this the type A model, the sociological research results and the researches to the illness behavior are discussed. Predictive factors of the disease and effects of psychological interventions were presented.

CONCLUSION FOR THE PRACTICE

The following variables are worked out as meaningful in the practice: social inequality and chronic emotional stress at the workplace, vital exhaustion, anxiety and depression, negative emotions, familial and social support, coping mechanisms and psychological interventions.

Spontaneous baroreflex sensitivity and heart rate variability are not superior to classic autonomic testing in older patients with type 2 diabetes

BACKGROUND

Early detection of cardiac autonomic neuropathy (CAN) permits individual risk stratification. Spontaneous heart rate variability (HRV) and baroreflex sensitivity (BRS) are suggested to be superior to classic autonomic testing in that they detect CAN earlier, with greater reliability, and do not require the patient's undue attention.

METHODS

To test that hypothesis, we studied 53 diabetic patients (mean age, 55 years) and 38 age-matched healthy control subjects (HC). Subjects underwent deep breathing, Valsalva maneuver, and orthostatic testing. Each abnormal test was counted as 1 point. A change in systolic blood pressure during standing of more than 10 mm Hg was graded with a single point; a decrease of more than 20 mm Hg received 2 points. A total score of zero was regarded as no CAN (noCAN), a score > or =4 as severe CAN (sCAN), and scores of 1 to 3 as mild CAN (mCAN). Spontaneous BRS was determined using the sequence technique. HRV was calculated as coefficient of variation (CV), high frequency power (HF) and low frequency power (LF).

RESULTS

Mean group values for HRV and BRS were: CV = 3.9+/-1.3; 4.0+/-1.3; 2.4+/-1.1; and 1.2+/-0.4; BRS = 8+/-3; 8+/-5; 5+/-2; and 2+/-2 msec/mm Hg for HC n = 38, noCAN n = 15, mCAN n = 26, and sCAN n = 12, respectively. BRS was similar in HC and patients with noCAN. In sCAN, BRS detected only 10 of 12 patients. HRV and BRS did not improve reclassification based on discriminant analysis.

CONCLUSION

BRS and HRV did not detect CAN in older diabetic patients better than classic autonomic testing.

Multiple system atrophy: new developments in pathophysiology and therapy

There have been substantial advances in the last five years in understanding the basic and clinical pathophysiology underlying multiple system atrophy (MSA). Identification of glial cytoplasmic inclusions has been the most important organizing principle for further elucidation of underlying mechanisms. Recently, several unexpected developments at the clinical level have been reported. In this article, we will focus on two of these: (1) the recognition that substantial autonomic function is retained in MSA but not modulated appropriately, and (2) a potent pressor effect from ingestion of water, which cannot be explained by currently understood physiologic and pathophysiologic mechanisms. In some patients, water has elicited a 50% increase in blood pressure and been more therapeutically effective than any available pressor drug. By careful coordination of the pressor effect of water and the depressor effect of carbohydrate-rich food, many patients with MSA can now have their blood pressure controlled without pharmacological intervention.

Familial orthostatic tachycardia due to norepinephrine transporter deficiency

Orthostatic intolerance (OI) or postural tachycardia syndrome (POTS) is a syndrome primarily affecting young females, and is characterized by lightheadedness, palpitations, fatigue, altered mentation, and syncope primarily occurring with upright posture and being relieved by lying down. There is typically tachycardia and raised plasma norepinephrine levels on upright posture, but little or no orthostatic hypotension. The pathophysiology of OI is believed to be very heterogeneous. Most studies of the syndrome have focused on abnormalities in norepinephrine release. Here the hypothesis that abnormal norepinephrine transporter (NET) function might contribute to the pathophysiology in some patients with OI was tested. In a proband with significant orthostatic symptoms and tachycardia, disproportionately elevated plasma norepinephrine with standing, impaired systemic, and local clearance of infused tritiated norepinephrine, impaired tyramine responsiveness, and a dissociation between stimulated plasma norepinephrine and DHPG elevation were found. Studies of NET gene structure in the proband revealed a coding mutation that converts a highly conserved transmembrane domain Ala residue to Pro. Analysis of the protein produced by the mutant cDNA in transfected cells demonstrated greater than 98% reduction in activity relative to normal. NE, DHPG/NE, and heart rate correlated with the mutant allele in this family.

CONCLUSION

These results represent the first identification of a specific genetic defect in OI and the first disease linked to a coding alteration in a Na+/Cl(-)-dependent neurotransmitter transporter. Identification of this mechanism may facilitate our understanding of genetic causes of OI and lead to the development of more effective therapeutic modalities.

Interaction between beta-adrenergic receptor stimulation and nitric oxide release on tissue perfusion and metabolism

Nitric oxide (NO) may be an important modulator of sympathetic tone. We used im and sc microdialysis in humans to characterize the interaction of NO synthase inhibition and adrenoreceptor stimulation on tissue perfusion, metabolism, and norepinephrine release. Microdialysis probes were perfused with L- or D-nitro-L-arginine-methyl-ester (100 micromol/L) followed by incremental doses of isoproterenol, epinephrine, or nitroprusside. Blood flow was estimated based on the ethanol dilution technique. In muscle, the increase in blood flow with isoproterenol was abolished by L-NAME. The ethanol ratio was 0.03 +/- 0.011 with D-NAME and 0.075 +/- 0.014 with L-NAME during isoproterenol treatment (1 micromol/L). The effect was less pronounced in adipose tissue. The vasodilatory effect of nitroprusside was similar with D- and L-NAME. L-NAME augmented isoproterenol- and epinephrine-induced glycerol release. Dialysate glycerol during 1 micromol/L isoproterenol was 47 +/- 6.7 micromol/L with D-NAME and 72 +/- 15 micromol/L with L-NAME. In skeletal muscle, dialysate norepinephrine during 1 micromol/L isoproterenol treatment was 0.73 +/- 0.17 and 1.3 +/- 0.15 nmol/L with D- and L-NAME, respectively. We conclude that NO synthase inhibition attenuates beta(2)-adrenoreceptor-mediated vasodilation and enhances beta-adrenoreceptor-mediated lipolysis. These effects are in part mediated through an increase in interstitial norepinephrine concentrations. The data are consistent with the idea that in humans, NO is important in modulating and ameliorating sympathetic effects in peripheral tissues.

New trends in the treatment of orthostatic hypotension

Nonpharmacologic and pharmacologic treatment can significantly attenuate the symptoms of orthostatic hypotension. Some of the interventions that are used to treat orthostatic hypotension have been known for decades. However, several new treatment strategies have been developed in recent years. New knowledge about the pathophysiology of orthostatic syndromes has been gathered that will strongly influence the way treatments are tailored to individual patients. For example, patients with and without residual autonomic function exhibit differential responses to certain treatments. A large subgroup of patients with severe autonomic failure show a profound pressor response to water drinking. This simple effect can be exploited to treat orthostatic and postprandial hypotension in some patients. New bioengineering technologies that attempt to replicate normal baroreflex mechanisms may become available for selected patients with central autonomic dysfunction.

Beta-2 adrenergic receptor gene variations and blood pressure under stress in normal twins

We tested the hypothesis that blood pressure (BP) responses to physical and mental stress are associated with polymorphisms in the beta-2 adrenergic receptor (AR) gene. We studied normotensive, young, monozygotic (MZ) and dizygotic (DZ) twins. The subjects underwent automated BP measurements at the brachial and digital arteries and were subjected to mental arithmetic and cold pressor stress. We used allele-specific PCR to genotype four single nucleotide polymorphisms in the beta-2 AR gene. The most functionally relevant polymorphism in the beta-2 AR gene, Arg16/Gly, was associated with systolic and diastolic BP under resting conditions, during mental arithmetic, and during the cold pressor test, as well as with the increase in diastolic BP during both forms of stress. These findings support a role for the beta-2 AR gene in BP regulation. They also indicate that the beta-2 AR gene influences the level of not only resting but also stress-related BP.

[Three therapeutic processes of inpatients with eating disorders compared with the Core Conflict Relationship Method (CCRT)]

In this article the results of a research with the CCRT-method on the psychotherapies of three in-patients suffering from eating disorders are presented. The CCRT describes recurrent internal and interpersonal relationship patterns in narratives. Each therapy session was recorded on tape and transcribed. The CCRT components were identified from the verbatim transcripts. All three patients clearly showed a negative self-perception and despite a more graded attitude regarding other people they felt rejected by the community throughout the entire therapy. The CCRT of each patient was different: patient 1. had conflicts between dependence and independence with increasing autonomy; patient 2. had great symbiotic desires, which at the beginning of the therapy were warded off with a performance ideal; patient 3. showed self-assertion and an increasing level of openness against the community, despite a high level of fear and self-isolation at the onset of therapy. Despite methodological deficiencies the CCRT method proved to be sensitive enough to show similarities and differences among the individual courses of treatment.

Orthostatic intolerance and the postural tachycardia syndrome: genetic and environment pathophysiologies. Neurolab Autonomic Team

Orthostatic intolerance is a common problem for inbound space travelers. There is usually tachycardia on standing but blood pressure may be normal, low or, rarely, elevated. This condition is analogous to the orthostatic intolerance that occurs on Earth in individuals with orthostatic tachycardia, palpitations, mitral valve prolapse, and light-headedness. Our studies during the Neurolab mission indicated that sympathetic nerve traffic is raised in microgravity and that plasma norepinephrine is higher than baseline supine levels but lower than baseline upright levels. A subgroup of patients with familial orthostatic intolerance differ from inbound space travelers in that they have an alanine-to-to-proline mutation at amino acid position 457 in their norepinephrine transporter gene. This leads to poor clearance of norepinephrine from synapses, with consequent raised heart rate. Clinical features of these syndromes are presented.