[Hyperhidrosis is a silent handicap]

Hyperhidrosis affects 2.8% of the population and has severe negative influence on life quality. The disease is represented in many specialties but can unfortunately be incorrectly treated or not treated at all. Primary hyperhidrosis is the most common form. Secondary hyperhidrosis is most often excluded by a few anamnestic data. Botulinum toxin and anticholinergics are adequate treatment options when aluminium chloride is insufficient. This article describes the disease from the physician's as well as the patient's perspective. Furthermore, examination procedures and treatment procedures are presented.

Effect of botulinum toxin concentration on reduction in sweating: a randomized, double-blind study

Dose-response studies of botulinum toxin for reduction of sweating are sparse in the literature. The aim of this study was to determine the most appropriate concentrations of Botox®, Dysport®, Xeomin® and NeuroBloc®, respectively, in order to achieve the greatest reduction in sweating, thus reducing the costs and increasing the safety of treatment. Four concentrations of each product were investigated. Intradermal injections of all products and concentrations were applied to the backs of 20 consenting subjects, in a randomized, double-blind manner. Areas of anhidrotic and hypohidrotic skin were measured with an iodine-starch test after 4, 8 and 12 weeks, respectively. Optimal concentrations were found to be 25 U/ml for Botox and Xeomin, approximately 100 U/ml for Dysport, and 50 U/ml for NeuroBloc. When comparing the mean anhidrotic area per unit for 100 U/ml of each product, the calculated dose conversion ratios were 1:1.6:1.2:1.3 (Botox:Dysport:Xeomin:NeuroBloc). If, instead, the optimal concentration for each product was compared, the dose conversion ratios were 1:4.8:1.3:2.2. Thus, it is crucial to consider botulinum toxin concentration in a treatment regimen.

Dose equivalence of two commercial preparations of botulinum neurotoxin type A: time for a reassessment?

BACKGROUND

The units of different preparations of botulinum neurotoxin type A (BoNT-A) have different potencies, and dosing recommendations for each product are not interchangeable. Historically, there has been debate concerning the dose-equivalence ratio that should be used in clinical practice.

METHODS

Published evidence was considered to establish an appropriate dose-conversion ratio for the two main commercially available preparations of BoNT-A--Dysport (Dp) and Botox (Bx).

RESULTS

Four key areas of evidence were identified: nonclinical and preclinical studies; studies exploring the diffusion characteristics and effects of complexing proteins; comparative experimental data from human studies; and clinical studies. Nonclinical data indicate that the principal reasons for differences in unit potency between the two products are dilution artefacts in the mouse assay. Use of saline as a diluent, at high dilutions, results in significant loss of potency in the Bx assay, whereas use of gelatin phosphate buffer in the Dp assay procedure protects the toxin during dilution. The published data on mouse assays show a Dp : Bx unit ratio range of 2.3-2.5 : 1 in saline and 1.8-3.2 : 1 in gelatin phosphate buffer. Data indicate that complexing proteins or size of the complex, which is highly pH sensitive, play no role in toxin diffusion and that Dp and Bx have similar diffusion characteristics when used at comparable doses. Randomized, controlled clinical studies indicate that 3 : 1 is more appropriate than 4 : 1, but the two products are not equivalent at this ratio. Comparative human experimental studies using the extensor digitorum brevis test, facial lines and anhidrotic action halo tests support dose-conversion ratios less than 3 : 1.

LIMITATIONS

Data comparing dose equivalence ratios from the non-clinical setting should be extrapolated into the clinical setting with some caution.

CONCLUSIONS

Dose-conversion ratios between Dp and Bx of 4 : 1 and greater are not supported by the recent literature.

Equipotent concentrations of Botox and Dysport in the treatment of palmar hyperhidrosis

There are indications that the dilution of botulinum toxin affects dose-response. This must be considered when comparing different products. The aim of this study was to estimate a concentration of Dysport in physiological saline that is approximately equivalent to Botox 100 U/ml with respect to anhidrotic and muscular effect. Thirty-six patients with primary palmar hyperhidrosis were treated with multiple intradermal injections of 0.02 ml botulinum toxin. Botox(R) was injected in one hand and Dysport in the other in a random order. The concentrations of Dysport were 200 U/ml (n=18), 150 U/ml (n=11) and 100 U/ml (n=7). Muscular effect was measured as the reduction in compound muscle action potential in 3 muscles in the hand and anhidrotic effect was indicated by an iodine-starch test 4 weeks after treatment. Dysport at 200 U/ml was more potent than Botox at 100 U/ml with regard to both anhidrotic and muscular effect. The equipotent concentration of Dysport, compared with Botox 100 U/ml, was found to be in the range 100-150 U/ml.

Anhidrotic effect of intradermal injections of botulinum toxin: a comparison of different products and concentrations

Botulinum toxin is used in various fields of medicine, including in the treatment of hyperhidrosis. Three products containing botulinum toxin are commercially available in Sweden; Botox, Dysport and Neurobloc. In the literature dose-response has varied with respect to these 3 products. We hypothesized that the dilution level of botulinum toxin is of importance for the effect and we therefore investigated anhidrosis after intradermal injections of each product in 3 different concentrations. Nine healthy subjects received 0.1 ml injections in the back. The anhidrotic areas were identified by an iodine-starch test after 3 weeks. When the 3 products were diluted to 100 U/ml level the achieved mean anhidrotic areas were approximately the same. This is in strong contrast with the large dose conversion factors suggested for intramuscular injections of the products. Furthermore, the lowest used concentrations for Botox(R) (25 U/ml) and Neurobloc (100 U/ml) led to the largest anhidrotic mean area per unit, respectively. The optimal concentration in this study was 25 U/ml for Botox, 100 U/ml for Dysport and 100 U/ml for Neurobloc, but for Botox and Neurobloc the optimal concentrations may be even lower.

Sweat gland morphology and periglandular innervation in essential palmar hyperhidrosis before and after treatment with intradermal botulinum toxin

BACKGROUND

Intradermal botulinum toxin (Btx) produces long-lasting relief of focal hyperhidrosis, but its mechanism of action is poorly understood.

OBJECTIVE

To study the effect of Btx A on the size and innervation of sweat glands in patients with palmar hyperhidrosis.

METHODS

Palmar skin biopsy was performed in 26 hyperhidrotic patients before scheduled Btx treatment and in 11 controls. Twelve of the patients also underwent biopsy 1 to 6 months after the Btx injections. Sweat gland morphology was investigated by light microscopy; the cross-sectional area of the secretory tubule and its lumen was measured by image analysis. Immunofluorescence (IF) with antibodies to the neural markers protein gene product 9.5 (PGP 9.5) and growth-associated protein 43 (GAP 43), and to vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP), was used to analyze the periglandular innervation.

RESULTS

The gross morphology of the sweat glands was similar in patients and controls, with no significant differences in tubular and luminal areas between the groups. After Btx treatment, the tubular dimensions remained unchanged, but the lumen tended to be smaller ( P = .07). Around the glands, increased GAP 43 staining indicating sprouting was seen within 3 months after Btx treatment ( P = .016); whereas the PGP 9.5 staining was decreased in most specimens ( P = .09) indicating lack of functional nerve growth. No change in VIP or CGRP immunoreactivity was observed.

CONCLUSIONS

The sweat glands appear structurally normal in hyperhidrotic patients before Btx therapy, whereas after therapy the luminal area of the gland is frequently diminished. The IF data GAP 43/PGP 9.5 suggest that Btx therapy induces long-standing functional denervation of the sweat glands, which might explain its anti-transpiratory efficacy.

Treatment of dyshidrotic hand dermatitis with intradermal botulinum toxin

BACKGROUND

Botulinum toxin (Btx A) has recently been used in the treatment of focal hyperhidrosis. Hyperhidrosis is also an aggravating factor in nearly 40% of patients with dyshidrotic hand eczema.

OBJECTIVE

The objective of this study was to evaluate the effect of intradermal injections of Btx A on dermatitis in patients with vesicular hand dermatitis.

METHODS

Ten patients with vesicular dermatitis were treated on one hand with intradermal Btx A (mean, 162 U BOTOX, Allergan Pharmaceuticals, Irvine, Calif) with the untreated side as a control.

RESULTS

Self-assessment at follow-up 5 to 6 weeks after injection on a 5-point scale (none, slight, moderate, good, or very good effect) showed that 7 of 10 patients experienced good or very good effect. A decrease in itching was shown with a visual linear analogue scale (VAS) for itching, with mean 39% on the treated side compared with an increase by 52% on the untreated side. These findings were supported by the evaluation of clinical signs. Six of 7 patients who experienced good or very good effect also had aggravating hand sweating or worsening during the summer.

CONCLUSION

Btx A can be a valuable alternative for patients with treatment-refractory hand eczema of the vesicular type, especially with hyperhidrosis or worsening during the summer.

Functional studies of Ycf3: its role in assembly of photosystem I and interactions with some of its subunits

The Ycf3 protein is essential for the accumulation of the photosystem I (PSI) complex and acts at a post-translational level. The sequence of Ycf3 is conserved in cyanobacteria, algae, and plants and contains three tetratrico-peptide repeats (TPR). TPRs have been shown to function as sites for protein-protein interactions. The mutations Y95A/Y96A and Y142A/W143A in the second and third TPR repeats lead to a modest decrease of PSI, but they prevent photoautotrophic growth and cause enhanced light sensitivity even though the accumulated PSI complex is fully functional. This phenotype can be reversed under anaerobic conditions and appears to be the result of photooxidative damage. A temperature-sensitive ycf3 mutant, generated by random mutagenesis of a conserved region near the N-terminal end of Ycf3, was used in temperature-shift experiments to show that Ycf3 is required for PSI assembly but not for its stability. Immunoblot analysis of thylakoid membranes separated by two-dimensional gel electrophoresis and immunoprecipitations shows that Ycf3 interacts directly with the PSI subunits PsaA and PsaD, but not with subunits from other photosynthetic complexes. Thus, Ycf3 appears to act as a chaperone that interacts directly and specifically with at least two of the PSI subunits during assembly of the PSI complex.

Functional studies of Ycf3: its role in assembly of photosystem I and interactions with some of its subunits

The Ycf3 protein is essential for the accumulation of the photosystem I (PSI) complex and acts at a post-translational level. The sequence of Ycf3 is conserved in cyanobacteria, algae, and plants and contains three tetratrico-peptide repeats (TPR). TPRs have been shown to function as sites for protein-protein interactions. The mutations Y95A/Y96A and Y142A/W143A in the second and third TPR repeats lead to a modest decrease of PSI, but they prevent photoautotrophic growth and cause enhanced light sensitivity even though the accumulated PSI complex is fully functional. This phenotype can be reversed under anaerobic conditions and appears to be the result of photooxidative damage. A temperature-sensitive ycf3 mutant, generated by random mutagenesis of a conserved region near the N-terminal end of Ycf3, was used in temperature-shift experiments to show that Ycf3 is required for PSI assembly but not for its stability. Immunoblot analysis of thylakoid membranes separated by two-dimensional gel electrophoresis and immunoprecipitations shows that Ycf3 interacts directly with the PSI subunits PsaA and PsaD, but not with subunits from other photosynthetic complexes. Thus, Ycf3 appears to act as a chaperone that interacts directly and specifically with at least two of the PSI subunits during assembly of the PSI complex.

Side-effects of intradermal injections of botulinum A toxin in the treatment of palmar hyperhidrosis: a neurophysiological study

Focal palmar hyperhidrosis can be effectively abolished by intradermal injections with botulinum toxin. Muscle weakness of finger grip has been reported as a reversible side-effect of this new treatment. The objective of this work was to measure muscular side-effects after treatment of palmar hyperhidrosis with botulinum toxin. As botulinum toxin has been used in the treatment of pain, we studied whether the toxin might influence afferent thin-fibre function by measuring temperature perception thresholds. Thirty-seven patients treated with botulinum toxin (Botox, Allergan Pharmaceuticals, Irvine, CA, USA) showed a decrease in compound muscle action potential (CMAP) for both abductor pollicis brevis (APB) and abductor digiti minimi (ADM) compared with pre-injection values on average by 64 and 36%, respectively, at 3 weeks which returned nearly to normal at 37 weeks. Muscle power for both finger abduction and finger opposition decreased to a lesser extent. Repetitive nerve stimulation and single fibre electromyography (EMG) showed a disturbed neuromuscular transmission. Thus, despite careful technique with small doses of botulinum toxin injected intradermally, the toxin diffuses to underlying muscles. With regard to the present results, one should be careful in using higher doses of Botox than 0.8 mU/cm(2) in the palmar skin above intrinsic muscles. No influence on thin-fibre function was seen.

Botulinum A toxin improves life quality in severe primary focal hyperhidrosis

Focal hyperhidrosis is a condition that may disturb emotional, social and professional life. Treatment options for severe cases are surgical sympathectomy and local chemical sweat gland denervation by intradermal injections of botulinum toxin A (Btx A). The Dermatology Life Quality Index (DLQI) is a simple validated questionnaire designed to measure and compare disability in different skin diseases. The aim of this study was to assess quality of life with the DLQI before and after treatment with botulinum toxin injections in a group of patients with severe hyperhidrosis. DLQI was administered to 58 randomly chosen patients before and after treatment. All patients answered the DLQI questionnaire prior to treatment and 53/58 at mean 5.2 months after treatment. The mean DLQI score in the 58 patients before treatment was 10.3 (2-23). In the group of 16/53 patients who had a relapse of sweating when answering the DLQI a second time, no significant improvement was seen [score 10.6 before and 8.8 after treatment (P = 0.21)]. In patients without relapse, a 76% improvement was obtained (DLQI was reduced from 9.9 to 2.4; P < 0.0001). The study showed that focal hyperhidrosis may considerably reduce life quality and the disability experienced by the patients can be largely reversed by botulinum toxin injections.

Palmar and axillary hyperhidrosis treated with botulinum toxin: one-year clinical follow-up

Focal hyperhidrosis is a common and sometimes handicapping condition for which the presently most effective treatment, sympathectomy, often leads to irreversible side-effects. We aimed to study effectiveness and tolerability of an alternative treatment with botulinum toxin injections over a period of one year for this condition. Twenty-eight patients with palmar (n = 19) and/or axillary (n = 13) hyperhidrosis were treated with intracutaneous injections of botulinum toxin (Botox(R)) 2 U/4 cm2. Sweat function was studied clinically and by objective measurements after treatment of one side. Treated and untreated sides, and pre- and post-treatment skin areas were compared. Subjective evaluation was performed after treatment of one side and 2-5 months after treatment of both sides. Duration of effect was controlled by a one-year follow-up. Sweating disappeared in eight out of 13 patients with axillary and in five out of 19 with palmar hyperhidrosis, and was reduced markedly in another five out of 13 and 10 out of 19 patients. Two-thirds of those treated for hand sweat noticed a slight and transient reduction of power of finger grip. No side-effects were noticed after treatment of axillary hyperhidrosis. We find intracutaneous injections of botulinum toxin with this technique safe and effective, and due to the relatively long duration of effect the treatment should be recommended before sympathectomy for focal hyperhidrosis.

Cosuppression of photosystem I subunit PSI-H in Arabidopsis thaliana. Efficient electron transfer and stability of photosystem I is dependent upon the PSI-H subunit

PSI-H is an intrinsic membrane protein of 10 kDa that is a subunit of photosystem I (PSI). PSI-H is one of the three PSI subunits found only in eukaryotes. The function of PSI-H was characterized in Arabidopsis plants transformed with a psaH cDNA in sense orientation. Cosuppressed plants containing less than 3% PSI-H are smaller than wild type when grown on sterile media but are similar to wild type under optimal conditions. PSI complexes lacking PSI-H contain 50% PSI-L, whereas other PSI subunits accumulate in wild type amounts. PSI devoid of PSI-H has only 61% NADP+ photoreduction activity compared with wild type and is highly unstable in the presence of urea as determined from flash-induced absorbance changes at 834 nm. Our data show that PSI-H is required for stable accumulation of PSI and efficient electron transfer in the complex. The plants lacking PSI-H compensate for the less efficient PSI with a 15% increase in the P700/chlorophyll ratio, and this compensation is sufficient to prevent overreduction of the plastoquinone pool as evidenced by normal photochemical quenching of fluorescence. Nonphotochemical quenching is approximately 60% of the wild type value, suggesting that the proton gradient across the thylakoid membrane is decreased in the absence of PSI-H.

The interaction between plastocyanin and photosystem I is inefficient in transgenic Arabidopsis plants lacking the PSI-N subunit of photosystem I

The PSI-N subunit of photosystem I (PSI) is restricted to higher plants and is the only subunit located entirely in the thylakoid lumen. The role of the PSI-N subunit in the PSI complex was investigated in transgenic Arabidopsis plants which were generated using antisense and co-suppression strategies. Several lines without detectable levels of PSI-N were identified. The plants lacking PSI-N assembled a functional PSI complex and were capable of photoautotrophic growth. When grown on agar media for several weeks the plants became chlorotic and developed significantly more slowly. However, under optimal growth conditions, the plants without PSI-N were visually indistinguishable from the wild-type although several photosynthetic parameters were affected. In the transformants, the second-order rate constant for electron transfer from plastocyanin to P700+, the oxidized reaction centre of PSI, was only 55% of the wild-type value, and steady-state NADP+ reduction was decreased to a similar extent. Quantum yield of oxygen evolution and PSII photochemistry were about 10% lower than in the wild-type at leaf level. Photochemical fluorescence quenching was lowered to a similar extent. Thus, the 40-50% lower activity of PSI at the molecular level was much less significant at the whole-plant level. This was partly explained by a 17% increase in PSI content in the plants lacking PSI-N.

The eight-amino acid internal loop of PSI-C mediates association of low molecular mass iron-sulfur proteins with the P700-FX core in photosystem I

The PSI-C subunit of photosystem I (PS I) shows similarity to soluble 2[4Fe-4S] ferredoxins. PSI-C contains an eight residue internal loop and a 15 residue C-terminal extension which are absent in the ferredoxins. The eight-residue loop has been shown to interact with PSI-A/PSI-B (Naver, H., Scott, M. P., Golbeck, J. H., Moller, B. L., and Scheller, H. V. (1996) J. Biol. Chem. 271, 8996-9001). Four mutant proteins were constructed. Two were modified barley PSI-C proteins, one lacking the loop and the C terminus (PSI-Ccore) and one where the loop replace the C-terminal extension (PSI-CcoreLc-term). Two were modified Clostridium pasteurianum ferredoxins, one with the loop of barley PSI-C and one with both the loop and the C terminus of PSI-C. Wild-type proteins and the mutants were used to reconstitute barley P700-FX cores lacking PSI-C, -D, and-E. Western blotting showed that PSI-CcoreLc-term binds to PS I, whereas PSI-Ccore does not. Without PSI-D the PSI-CcoreLc-term mutant accepts electrons from FX in contrast to PSI-C mutants without the loop. Flash photolysis of P700-FX cores reconstituted with C. pasteurianum ferredoxin showed that only the ferredoxin mutants with the loop accepted electrons from FX. From this, it is concluded that the loop of PSI-C is necessary and sufficient for the association between PS I and PSI-C, and that the loop is functional as an interaction domain even when positioned at the C terminus of PSI-C or on a low molecular mass, soluble ferredoxin.

Anatomical and neurological correlates of acute and chronic visuospatial neglect following right hemisphere stroke

Anatomical and neurological correlates of visuospatial neglect were studied in 53 patients with a CT-documented right hemisphere stroke. Evidence of neglect at the acute stage poststroke was strongly related to large lesions involving the middle temporal gyrus and/or the temporo-parietal paraventricular white matter. Thus, out of 18 patients with evidence of visuospatial neglect at the acute stage, 12 showed a lesion in the middle temporal gyrus and/or the deep temporo-parietal white matter. Among the 35 patients that failed to show visuospatial neglect, only one patient had a lesion within these areas. Comparing those patients who recovered from neglect with those that did not, a high correlation was found between persisting neglect and a lesion involving the paraventricular white matter in the temporal lobe. On the basis of above findings, it was suggested that a simultaneous damage to the cortico-thalamic system for regulation of arousal and to the neural systems mediating visual orienting, is likely to be followed by persisting neglect symptoms.

Lateralization of cutaneous inflammatory responses in patients with unilateral paresis after poliomyelitis

Unilateral paresis remaining after poliomyelitis may affect the expression of inflammatory diseases by lateralization of the disease manifestations. The purpose of this study was to assess the impact of the unilateral paresis after poliomyelitis on lateralization of neurogenic inflammation and immune responsiveness. The delayed-type hypersensitivity (DTH) reaction to tuberculin was used as an in vivo measure of antigen-specific T lymphocyte reactivity. Assessment of axon reflex vasodilatation was simultaneously employed to test for neurogenic inflammation. Fourteen of the 16 polio patients displayed a positive DTH reaction to tuberculin. All but two showed weaker DTH reaction on the paretic- compared to the contralateral-side (P = 0.001). Magnitude of electrically evoked axon reflexes significantly correlated to asymmetries of DTH responses. We conclude that damage of lower motor neuron leads to ipsilateral down-regulation of T cell-mediated cutaneous inflammation. This lateralization of DTH responses is related to deficiencies in motor and sympathetic innervation of the paretic extremity.

Reconstitution of barley photosystem I with modified PSI-C allows identification of domains interacting with PSI-D and PSI-A/B

The PSI-C subunit of photosystem I shows similarity to soluble 2[4Fe-4S] ferredoxins. Alignment analysis clearly shows that PSI-C contains an 8-residue internal loop and a 15-residue C-terminal extension that are absent in the ferredoxins. The remaining residues in PSI-C are likely to be folded in a way similar to the soluble 2[4Fe-4S] ferredoxins. Two modified PSI-C subunits lacking either the 8-residue loop or 10 residues of the C terminus were expressed in Escherichia coli and used to reconstitute a barley P700-FX core prepared to specifically lack PSI-C, PSI-D, and PSI-E. As shown by EPR spectroscopy, the modified proteins carry two [4Fe-4S] clusters with characteristics similar to those of native PSI-C. Western blot analysis of the reconstituted photosystem I complexes showed that the modified PSI-C proteins bind to the P700-FX core. Flash photolysis revealed that in photosystem I complexes reconstituted in the presence of PSI-D with the C-terminally deleted PSI-C, the FA/FB back-reaction was less efficiently restored than with wild-type PSI-C. The loop-deleted PSI-C was even less efficient. We attribute these differences to altered binding properties of the modified proteins. Comparison of reconstitutions performed in the presence and absence of PSI-D shows that the loop-deleted PSI-C is unable to bind without PSI-D, whereas the C-terminally deleted PSI-C binds only weakly with PSI-D. These results imply that the internal loop of PSI-C interacts with the PSI-A/B heterodimer and that the C terminus of PSI-C interacts with PSI-D.

Autonomic and thermal sensory symptoms and dysfunction after stroke

BACKGROUND AND PURPOSE

Symptoms interpreted as unilateral disturbances of autonomic function, such as coldness, dryness, sweating, and trophic changes, are well known but incompletely understood clinical problems after stroke. The present study provides data related to the incidence and mechanisms behind such symptoms.

METHODS

Temperature perception thresholds, skin temperatures, evaporation rates, and skin blood flow responses were measured bilaterally in 37 stroke patients aged 58 +/- 13 years (mean +/- SD) and in a control group of 15 patients aged 64 +/- 15 years with a single transient ischemic attack.

RESULTS

Of the 37 stroke patients, 43% reported a sensation of coldness in the contralesional side of the body. Basal skin blood flow and temperature were relatively lower in the contralesional side. There was an excess of evaporation in the contralesional side after brain stem lesions and in the ipsilesional side after hemispheric lesions. Vasomotor reflex asymmetries occurred in 34% of the patients and were due to weak vasodilator or vasoconstrictor reflexes in the ipsilesional side. These abnormalities correlated significantly to sensations of unilateral coldness, hypalgesia, and thermohypesthesia in the contralesional side and anatomically to lesions in spinothalamo-cortical pathways.

CONCLUSIONS

Focal central nervous system lesions due to stroke may result in symptoms and measurable evidence of unilateral disturbance of skin sympathetic function. Vasomotor asymmetries are probably due to lesions of vasomotor pathways descending uncrossed. Subjective coldness may be due to disturbed central processing.

The importance of non-charged amino acids in antibody binding to Humicola lanuginosa lipase

The antigenicity of 36 Humicola lanuginosa lipase (HL) variants, generated by site directed mutagenesis, was compared with that of the unchanged enzyme. Polyclonal antibodies raised against variant lipases were investigated and compared with the antibodies raised against the wild type lipase in an ELISA competition assay. The results showed that exchange of charged amino acids with polar residues in surface epitopes of HL, results in a tighter binding of the antibody to the epitope. Four amino acids (Trp at position 89, Asp at positions 96 and 254 and Phe at position 211) were found to be essential for antibody binding in each their epitope of the wild type enzyme.

Lateralization of T-lymphocyte responses in patients with stroke. Effect of sympathetic dysfunction?

BACKGROUND AND PURPOSE

A number of clinical observations indicate that stroke affects the course of immune-mediated diseases by lateralization of the disease manifestations, such as arthritis. The purpose of this study was to assess the impact of early stroke on lateralization of immune responsiveness.

METHODS

The delayed-type hypersensitivity (DTH) reaction to purified protein derivative was used as an in vivo measure of antigen-specific T-lymphocyte reactivity. Assessment of axon reflex vasodilation was simultaneously used to test for cutaneous sympathetic activity.

RESULTS

There were no significant differences with regard to lateralization of DTH reactivity when all stroke patients were tested. However, patients with minor stroke displayed a significant (P < .001) decrease of DTH reaction on the paretic side compared with the contralateral side. In contrast, patients with major stroke showed a significant increase (P = .022) of DTH reaction on the paretic side. Patients with left hemiparesis had a significantly greater (P = .045) DTH response on the affected side than patients with a right hemiparesis. In addition, only the patients with motor deficit but not with sensory deficit or aphasia displayed side differences in DTH responses. When electrically evoked axon reflexes were studied in relation to DTH reactions, a significant correlation (r = .64; P < .001) was found between side asymmetries of DTH responses and side asymmetries of axon reflexes in an innervated skin area. No similar relation was present in skin areas where cutaneous sympathetic activity had been blocked by regional anesthesia.

CONCLUSIONS

Early stroke lateralizes T-cell-mediated cutaneous inflammation. This effect depends on (1) the localization of the brain lesion, (2) the clinical course of the disease, and (3) the presence of motor deficit and may be mediated by (4) alteration of the cutaneous sympathetic nerve traffic.

The vasodilating effect of spinal dorsal column stimulation is mediated by sympathetic nerves

Spinal dorsal column stimulation has been used in the treatment of a patient with a painful vasospastic condition in the right arm following surgical sympathectomy on the left side. After sympathectomy the left arm became constantly dry and warm and consistently lacked skin vasomotor (laser Doppler flowmetry) responses to arousing stimuli, indicating a complete loss of sympathetic vasomotor innervation. The return of minimal sudomotor (skin resistance) responses to mental stress 2 years after sympathectomy indicated a partial reinnervation of sweat glands. Immediately after sympathectomy, the contralateral right arm became increasingly cold and cyanotic and the patient complained of chronic painful coldness and severe cold-intolerance in the right arm. Attempts to pharmacologically vasodilate the arm with felodipine did not affect the local vasoconstriction and pain. Dorsal column stimulation (associated with symmetrical paraesthesia in both arms) induced an immediate and marked (ten-fold) increase in skin blood flow in the right arm (and in the leg), whereas skin blood flow in the left arm remained unaffected. The lack of vasomotor response in the left arm was not due to maximal vasodilatation at rest, since skin blood flow in the left arm showed a normal capacity for axon reflex vasodilatation following antidromic activation of sensory afferents. The results suggest that the marked vasodilatation induced by dorsal column stimulation is mediated by sympathetic vasomotor fibres, via modulation of central neuronal circuits involved in the regulation of skin sympathetic discharge.