Autoantibodies in childhood opsoclonus-myoclonus syndrome

Opsoclonus-myoclonus syndrome or Dancing Eye Syndrome (OMS/DES) is a rare neurological disorder of children, which associates with neuroblastoma (NB) in approximately 50% of cases. We examined sera from five patients with (OMS-NB(+)) and five without NB (OMS-NB(-)) for autoantibodies. OMS-NB(-) IgG bound to the surface of a NB cell line, whereas IgG from OMS-NB(+) and from NB patients without OMS/DES bound only to permeabilised cells. Both OMS-NB(+) and OMS-NB(-) reduced proliferation of NB cells. We also present a case report of a child with OMS/DES without NB who made a complete recovery without treatment. Serum antibodies at presentation bound to the surface and decreased NB cell proliferation but had decreased 9 weeks later when the child was asymptomatic. These results demonstrate that sera from some OMS/DES patients contain IgG antibodies that are potentially pathogenic.

High-affinity DNA binding sites for H-NS provide a molecular basis for selective silencing within proteobacterial genomes

The global transcriptional regulator H-NS selectively silences bacterial genes associated with pathogenicity and responses to environmental insults. Although there is ample evidence that H-NS binds preferentially to DNA containing curved regions, we show here that a major basis for this selectivity is the presence of a conserved sequence motif in H-NS target transcriptons. We further show that there is a strong tendency for the H-NS binding sites to be clustered, both within operons and in genes contained in the pathogenicity-associated islands. In accordance with previously published findings, we show that these motifs occur in AT-rich regions of DNA. On the basis of these observations, we propose that H-NS silences extensive regions of the bacterial chromosome by binding first to nucleating high-affinity sites and then spreading along AT-rich DNA. This spreading would be reinforced by the frequent occurrence of the motif in such regions. Our findings suggest that such an organization enables the silencing of extensive regions of the genetic material, thereby providing a coherent framework that unifies studies on the H-NS protein and a concrete molecular basis for the genetic control of H-NS transcriptional silencing.

IgG subclass distribution of autoantibodies in pediatric opsoclonus–myoclonus syndrome

Opsoclonus-myoclonus syndrome (OMS) in children is a rare disorder including a severe eye movement disturbance, myoclonia, ataxia and often developmental retardation. Both OMS forms, idiopathic or neuroblastoma-associated (paraneoplastic), have been suspected to be autoimmune. Recently, autoantibodies have been found in OMS sera. We here show that autoantibodies in OMS, both intracellular and surface binding, belong mainly to the IgG3 subclass, although the total serum IgG3 level is normal. These results support the autoimmune hypothesis and point to a protein autoantigen as antigenic target.

Outcome of interventions to identify family history and risk management for women with breast cancer in the ambulatory setting

6121

Background: In 2002, Kansas City Cancer Center (KCCC) performed a quality improvement (QI) project to evaluate how breast cancer patients were being assessed for family history and cancer risk management. A self-administered family history questionnaire was developed to improve the thoroughness of family history collected and education of clinicians was completed to improve the recognition of risk factors based on ASCO guidelines. Methods: Chart audits on 210 women with breast cancer at KCCC, were completed in the second quarter of 2005. All patients were under the age of 65, not undergoing chemotherapy. A risk management tool was developed. Scoring criteria for 2002 was replicated in 2005 as listed in the table . Results: In 2002, 171 pts (89%) had level 1 or 2 family history assessed compared to 207 pts (99%) in 2005, p<0.0001. In 2002, 47% had 3 generations assessed compared to 84% in 2005, p<0.0001. In 2002 and 2005, some risk factor management occurred in both groups, and was equal, 78% and 80% respectively (p=ns). Of those that had risk management 33% had level 1 in 2002 compared to 3% in 2005 (p<0.0001) a 91% reduction in identifying risk without subsequent management. In 2002, 58% had level 2, compared to 71% in 2005 (p=0.02) a 23% improvement in identification & management of risk. In 2002, 9% had level 3 compared to 26% in 2005 (p<0.0001) a 183% improvement in patients with a detailed risk assessment and/or genetic referral. Conclusions: By improving the assessment of family history and education of providers, women with breast cancer are receiving more information to reduce their risk for recurrence and complications. Patients who were identified as high risk for BRCA1 or BRCA2 mutations were referred to either a nurse practitioner or genetic counselor.

[Table: see text]

No significant financial relationships to disclose.

A collaborative demonstration project: Depression screening in patient with cancer

18556

Background: A demonstration project testing the feasibly of implementing a depression screening work flow algorithm was initiated by the anti-depression committee at one of six ambulatory care sites in the Kansas City Cancer Center (KCCC) system. The object of the study was to develop a process of work flow that would assist in identifying patients with depression and facilitate appropriate interventions by providers. Methods: A flow chart was developed illustrating critical decision-making points in the screening for depression by physicians and nurse practitioners (NP). The population included half radiation therapy and the other half chemotherapy. Patients completed the PHQ-2 a two question prescreen to assess initial symptoms of depression, including feeling depressed, down or hopeless and/ or little interest or pleasure in activities. A positive response to one of these 2 questions prompted the administration of the PHQ-9 a validated depression screening instrument. The PHQ-9 scoring criteria was used to assist the physician and NP with taking the appropriate action such as the initiation of antidepressant therapy and/or referral to mental health provider, follow up for subsequent appointments and/or reassessment. Results: Seventy-one patients were tracked to evaluate the process of recognition and management of depression from April 2004 to January 2005. Of the 71 patients 37% (N = 26) scored positive on at least one question on the two question prescreen. Of the 26 patients scoring positive 27% (N = 7) of these patients had less than 3 follow up visits while 73 % (N = 19) had greater than 3 follow-up visits by the KCCC providers. Of the patients that answered positively to one of the two prescreen questions 69% (N = 18) completed the full PHQ-9 and their scores were recorded. Conclusions: The development of a new model in a community-based oncology practice allows for integrating clinically proven techniques for diagnosing and treating depression. It will allow for the committee to make recommendations for changes in the process before it is implemented on a larger scale at all KCCC outpatient sites.

No significant financial relationships to disclose.

Serum antibodies in epilepsy and seizure-associated disorders

OBJECTIVE

To investigate whether autoantibodies to ion channels and other neural antigens are present in the sera of patients with epilepsy and seizure-related diseases.

METHODS

Sera were obtained from 139 patients, including 26 with preexisting autoimmune disease, 46 in whom an autoimmune basis was suspected, and 67 with drug-resistant epilepsy. The sera were assayed for antibodies to voltage-gated potassium (VGKC) and calcium (VGCC) channels, glutamic acid decarboxylase (GAD), gangliosides, glutamate receptor type 3, cardiolipins, DNA, and nuclear antigens; the results were compared with results from a large cohort of healthy and disease controls.

RESULTS

Increased titers of VGKC antibodies (>100 pM) were detected in 16 of 139 (11%) patients with seizures but only 1 control (0.5%). Eight VGKC-positive patients presented with an acute/subacute illness, and 5 of these had the highest VGKC antibodies; 3 patients improved spontaneously, another 5 patients responded well to immunomodulatory therapy. The other VGKC-positive patients had longer disease duration (>6 years) and intermediate levels of antibodies; immunotherapies have not been tested in this group. Very high levels of GAD antibodies (>1,000 U) were found in an additional 3 patients (2.1%) with long-standing drug-resistant epilepsy.

CONCLUSIONS

The presence of autoantibodies to voltage-gated potassium channels and glutamic acid decarboxylase suggests that the immune system may contribute to certain forms of epilepsy or seizure-associated disorders. Further studies are needed to determine whether the antibodies are pathogenic.

Alpha7-acetylcholine receptor antibodies in two patients with Rasmussen encephalitis

Rasmussen encephalitis (RE) sera were screened for antibodies to human alpha7 nicotinic acetylcholine receptors (nAChRs) using electrophysiology, calcium imaging, and ligand binding assays. Sera from two of nine patients with RE blocked ACh-induced currents through alpha7 nAChRs and the ACh-induced rise in intracellular free calcium ([Ca2+]i) and inhibited (125)I-alpha-bungarotoxin binding in cells expressing alpha7 nAChRs. Thus, the alpha7 nAChR is a potential target for pathogenic antibodies in patients with RE.

Anti-glial nuclear antibody: marker of lung cancer-related paraneoplastic neurological syndromes

We describe a new antibody, called anti-glial nuclear antibody (AGNA), in patients with paraneoplastic neurological syndromes (PNS) and small-cell lung carcinoma (SCLC). AGNA was initially identified in 24 sera of our archives by immunohistochemistry on rat cerebellum. AGNA positive sera showed a characteristic nuclear staining of the Bergmann glia in the Purkinje cell layer. Immunoblots and probing a cerebellar expression library with AGNA sera did not identify the antigen. Twenty of the 24 patients with AGNA had PNS and all but two had lung cancer. AGNA was identified in 13/113 (11.5%) patients with SCLC compared with 0/122 with other types of cancer (p<0.0001). The frequency of AGNA was not higher than expected for the presence of SCLC in the different PNS subtypes except in LEMS (p=0.0002). AGNA was present in 13/30 (43%) of LEMS patients with SCLC, compared with 0/19 of LEMS patients without cancer (p=0.0006). We conclude that the recognition of AGNA is helpful since this antibody is found in PNS associated with SCLC, particularly LEMS, in which other onconeural antibodies are absent.

[Evidence-based medicine for the public]

The methods of evidence-based medicine demand high quality and up-to-date medical information. Ideally, this information is based on data from controlled clinical trials. When such external evidence is available, it provides a base for an effective patient-physician consultation, and is also essential for the consumer friendly presentation of medical information. This article sketches the international and German developments and approaches to preparing and maintaining evidence-based patient information and its influences on the models of physician-patient communication.

Leitlinien

Now more than ever physicians need effective management of the constantly increasing flood of medical information. The authors discuss possibilities for developing clinical guidelines as a core element of this information management and the requirements of these possibilities. The development of clinical guidelines is a process also suitable for involving patient and consumer expertise in health care. Models of involving patients are described and how these processes can build an important base for shared decision making of physicians and patients.

Absence of antibodies to glutamate receptor type 3 (GluR3) in Rasmussen encephalitis

OBJECTIVE

To determine the prevalence of serum antibodies to the ionotropic glutamate receptor 3 (GluR3) in patients with Rasmussen encephalitis (RE), a severe epileptic disorder, and to compare with serum from control subjects and patients with intractable epilepsy (IE).

METHODS

The authors looked for serum immunoglobulin (Ig) G antibodies to GluR3 in 30 patients with RE, including two patients who had plasma exchange and 12 who had been treated with IV Igs with varying results, and 49 patients with IE and 23 healthy individuals, using ELISA with GluR3B peptide, Western blot analysis of recombinant full-length GluR3, immunoprecipitation of [35S]- and [125I]-labeled GluR3 extracellular domains, immunohistochemistry on rat brain sections, and electrophysiology of GluR3 expressed in Xenopus oocytes.

RESULTS

Low levels of antibodies to the GluR3B peptide were detected using ELISA in only 4 of the 79 patients with epilepsy (2 with RE and 2 with IE); binding to GluR3B in other sera was shown to be nonspecific. One other patient with IE had antibodies to recombinant GluR3 on Western blot analysis. However, none of the sera tested precipitated either the [35S]- or the [125I]-labeled GluR3 domains; none bound to rat brain sections in a manner similar to rabbit antibodies to GluR3; and none of the nine sera tested affected the electrophysiologic function of GluR3.

CONCLUSIONS

GluR3 antibodies were only infrequently found in Rasmussen encephalitis or intractable epilepsy.

Hu and voltage-gated calcium channel (VGCC) antibodies related to the prognosis of small-cell lung cancer

PURPOSE

Hu antibodies previously have been associated with longer survival of patients with small-cell lung cancer (SCLC). Voltage-gated calcium channel (VGCC) antibodies play a pathogenic role in Lambert Eaton myasthenic syndrome, which is also associated with SCLC. These antibodies may reduce tumor growth in patients with the neurologic disease, but it is not clear whether they provide prognostic information in those without neurologic symptoms.

PATIENTS AND METHODS

Two hundred patients with SCLC (age 39 to 79 years; mean, 62.3 years; 129 males and 71 females) receiving chemotherapy were studied for the presence of Hu and VGCC antibodies. Sera were examined for Hu antibodies by an in vitro transcription-translation-based immunoprecipitation technique and by immunohistochemistry/dot blot. VGCC (P/Q subtype) antibodies were detected by radioimmunoassay. Survival analysis was used to analyze the data. Results Hu antibodies were detected in 51 of 200 patients (25.5%) by in vitro transcription-translation-based immunoprecipitation and in 37 of 200 patients (18.5%) by immunohistochemistry or dot blot, whereas VGCC antibodies were detected in only 10 of 200 patients (5%). The presence of Hu antibodies did not correlate with VGCC antibodies, and there was no association between Hu or VGCC antibodies and the extent of disease or survival.

CONCLUSION

Hu and VGCC antibodies are found in a proportion of SCLC patients, irrespective of neurologic symptoms, but their presence does not correlate with the prognosis of the SCLC.

The evaluation of the no-independent vasodilatative effect of iloprost in isolated perfused Guinea pig hind limbs

AIM

In critical limb ischemia vasodilatators play an important role in the treatment of the disease. Considering that the endothelium is seriously damaged in these patients, we wanted to evaluate if the vasodilatative effect of iloprost does or does not depend on the endothelium by using the model of the isolated perfused guinea pig hind limb.

METHODS

A catheter was inserted via the distal aorta and common iliac artery. After stabilization, iloprost was administered at a dosage of 0.1 microM. In a subsequent series of experiments precontraction of the peripheral vascular bed was achieved with 40 mM KCl followed by 0.1 microM iloprost. In a 3rd series of experiments L-NAME (100 microM) was administered after the equilibration period for 30 minutes, followed by 0.1 microM iloprost. In the 4th series of experiments, after the administration of L-NAME (100 microM), KCl (40 mM) was administered to precontract the vascular bed and iloprost 0.1 microM was added.

RESULTS

The administration of iloprost alone and after addition of KCL induced a significant decrease in vascular resistance(-49.6+/-14.1% [x+/-SEM, n=7]). The addition of L-NAME did not affect vascular resistance. The consecutive addition of iloprost reduced vascular resistance significantly (-4.2+/-0.7% [x+/-SEM, n=7]). After addition of L-NAME 100 microM and precontraction with KCl 40 mM, iloprost once again significantly reduced peripheral vascular resistance (-51.5+/-14.4% [x+/-SEM, n=6]). Reduction of peripheral vascular resistance by iloprost was comparable to that without L-NAME.

CONCLUSION

Our data show that iloprost at a dosage of 0.1 microM achieves a significant reduction in peripheral vascular resistance and that the vasodilatative effect of iloprost is independent of NO. Iloprost therefore seems to be an ideal vasodilatative drug for the treatment of patients with impaired endothelial function.

Astrocytes in injured adult rat spinal cord may acquire the potential of neural stem cells

It has been well documented that in adult rats astrocytes in the subventricular zone and subgranular layer of the dentate gyrus are neural stem cells. Elsewhere in the CNS astrocytes are not generally recognized as stem cells. Here we describe nestin expression in a population of astrocytes in the spinal cord of adult rat following cord injury. In either hemitransectioned or longitudinally cut spinal cord, there was widespread nestin expression in astrocytes of both the gray and white matters. Isolation of the lateral part of the spinal cord from the central canal region, where stem cells may reside, could not block the appearance of nestin-immunoreactive astrocytes in the lateral cord, and none of them showed Fast DiI labeling after the central canal ependyma had been labeled by the dye, indicating that the nestin-immunoreactive astrocytes can evolve locally in the lateral cord. They were found to be undergoing a process of de-differentiation. Culture of the nestin-immunoreactive astrocytes of the lateral cord generated neurospheres, the cells of which had the ability of self-renewal, and were able to differentiate into neurons, astrocytes, or oligodendrocytes. Taken together, the results indicate that the astrocytes in injured adult rat spinal cord may acquire the potential of neural stem cells.

P/Q type calcium-channel antibodies in paraneoplastic cerebellar degeneration with lung cancer

Raised levels of P/Q type voltage-gated calcium-channel (VGCC) antibodies were found in 16 (41%) of 39 patients with paraneoplastic cerebellar degeneration (PCD) and Hu antibodies were found in nine (23%). Seven of the 16 VGCC antibody-positive patients had Lambert-Eaton myasthenic syndrome (LEMS). Seven of 15 CSF samples had VGCC antibodies, with evidence of intrathecal synthesis in four. VGCC antibodies should be looked for in PCD, even if there are no symptoms of LEMS, and may be related to the cerebellar dysfunction.

Epigastric hernia and its etiology

BACKGROUND

Controversies still prevail as to how exactly epigastric hernia occurs. Both the vascular lacunae hypothesis and the tendinous fibre decussation hypothesis have proved to be widely accepted as possible explanations for the etiology.

PATIENT

We present a patient who suffered from early-onset epigastric hernia.

CONCLUSIONS

We believe the identification of the ligamentum teres and its accompanying vessel at its fascial defect supports the vascular lacunae hypothesis. However, to further our understanding, biopsy of the linea alba in patients with epigastric hernias is indicated.

Calcium channel subtypes contributing to acetylcholine release from normal, 4-aminopyridine-treated and myasthenic syndrome auto-antibodies-affected neuromuscular junctions

1 Acetylcholine release at the neuromuscular junction relies on rapid, local and transient calcium increase at presynaptic active zones, triggered by the ion influx through voltage-dependent calcium channels (VDCCs) clustered on the presynaptic membrane. Pharmacological investigation of the role of different VDCC subtypes (L-, N-, P/Q- and R-type) in spontaneous and evoked acetylcholine (ACh) release was carried out in adult mouse neuromuscular junctions (NMJs) under normal and pathological conditions. 2 omega-Agatoxin IVA (500 nM), a specific P/Q-type VDCC blocker, abolished end plate potentials (EPPs) in normal NMJs. However, when neurotransmitter release was potentiated by the presence of the K(+) channel blocker 4-aminopyridine (4-AP), an omega-agatoxin IVA- and omega-conotoxin MVIIC-resistant component was detected. This resistant component was only partially sensitive to 1 micro M omega-conotoxin GVIA (N-type VDCC blocker), but insensitive to any other known VDCC blockers. Spontaneous release was dependent only on P/Q-type VDCC in normal NMJs. However, in the presence of 4-AP, it relied on L-type VDCCs too. 3 ACh release from normal NMJs was compared with that of NMJs of mice passively injected with IgGs obtained from patients with Lambert-Eaton myasthenic syndrome (LEMS), a disorder characterized by a compromised neurotransmitter release. Differently from normal NMJs, in LEMS IgGs-treated NMJs an omega-agatoxin IVA-resistant EPP component was detected, which was only partially blocked by calciseptine (1 micro M), a specific L-type VDCC blocker. 4 Altogether, these data demonstrate that multiple VDCC subtypes are present at the mouse NMJ and that a resistant component can be identified under 'pharmacological' and/or 'pathological' conditions.

[Structural quality of acute internal medicine rheumatology clinics--Project Group of the Association of Rheumatologic Acute Clinics]

A study group representing the VRA (Association of Rheumatology Clinics in Germany) has worked out the structural quality paper presented here. Five guidelines for structural quality have been established by the VRA and are laid out in this paper. Required space and personnel for implementing these guidelines are considered. A highly competent, multi-disciplinary team must be available to ensure the long-term quality of in-patient treatment of rheumatic patients, the majority of whom are chronically ill and are suffering from chronic pain of varying intensity which restricts their daily activities. The necessity for such in-patient treatment is reflected in a 6-point-questionnaire (draft) adapted to the Appropriateness Evaluation Protocol. Considering the introduction of a flat-rate fee system (DRG-system) the structural quality paper describes the implementation of a specified electronic data processing documentation which is linked to a central hospital information system. According to the concept of benchmarking, the paper takes into account future developments of the German health system. It will be adjusted continuously to changing political guidelines for health services.

In polymyalgia rheumatica serum prolactin is positively correlated with the number of typical symptoms but not with typical inflammatory markers

OBJECTIVES

Hyperprolactinaemia has been associated with the active phase of human systemic lupus erythematosus and rheumatoid arthritis. In the present study, we investigated the role of prolactin (PRL) in relation to the number of typical symptoms and serum markers of systemic inflammation in patients with polymyalgia rheumatica (PMR).

METHODS

One hundred and two PMR patients presented with typical symptoms such as adynamia, bilateral muscular pain in shoulders, upper arms or neck, bilateral muscular pain in the pelvic girdle, headache, morning stiffness, arthralgia, symptoms of depression, fever, initial weight loss (>4 kg/month), and transient visual symptoms. If one of the mentioned symptoms was present, the corresponding item was scored with one point (maximum unweighted item points=10). PRL, interleukin-2 (IL-2), IL-6, IL-1 receptor antagonist (IL-1ra), tumour necrosis factor (TNF), soluble IL-2 receptor (sIL-2R), and soluble vascular cell adhesion molecule (sVCAM) were measured by enzyme-linked immunosorbent assay in patients and 31 age-matched healthy controls.

RESULTS

Fifteen PMR patients with elevated PRL had a higher number of symptoms as compared with patients with normal levels (P=0.003). PRL was correlated with the number of symptoms (all PMR patients: r(rank)=+0.380, P<0.001) and duration of morning stiffness (all PMR patients: r(rank)=+0.335, P=0.002) irrespective of prior corticosteroid treatment. However, PRL did not correlate with markers of systemic inflammation such as erythrocyte sedimentation rate, C-reactive protein, serum IL-1ra, IL-2, sIL-2R, IL-6, TNF, and sVCAM.

CONCLUSION

The number of symptoms in PMR patients was positively correlated with PRL, but PRL was not correlated with serum markers of inflammation. This indicates that PRL is not a pro-inflammatory stimulus in patients with PMR. The inter-relationship between PRL and symptoms or duration of morning stiffness may be more a sign of central nervous system involvement, as it can be observed in people with depressed mood or under psychological stress.

A role for autoantibodies in some cases of acquired non-paraneoplastic gut dysmotility

BACKGROUND

Antibody-mediated autoimmunity underlies a diverse range of disorders, particularly in the nervous system where domains of ion channels and receptors are potential targets. The aetiology of many adult-onset conditions of severe gut dysmotility is not known. We looked for antibodies to neuronal antigens in patients with severe (slow-transit-type) constipation (STC).

METHODS

Eleven sera from adult-onset STC patients and 18 from childhood onset cases were tested by routine immunoprecipitation assays for antibodies against neuronal antigens including voltage-gated potassium channels (VGKCs), calcium channels (VGCCs), both muscle and neuronal acetylcholine receptor and glutamic acid decarboxylase (GAD). Results were compared with positive and negative control populations.

RESULTS

Two of the 11 sera from patients with adult-onset STC showed highly positive anti-VGKC antibodies. Both had onset of symptoms de novo in adulthood without evidence of autoimmune, neoplastic or neurological disease. One of these patients, and one other, had anti-GAD antibodies. None of the childhood-onset STC had evidence of anti-neuronal antibodies.

CONCLUSIONS

Anti-neuronal antibodies are found in some patients with a condition of severe acquired gut dysmotility of previously unknown aetiology. Future studies may demonstrate an autoimmune role for such antibodies.

Differential expression of AMPA receptor subunits in dopamine neurons of the rat brain: a double immunocytochemical study

We have examined the distribution of dopamine neurons expressing alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptor subunits (glutamate receptors 1, 2/3 and 4) in the A8-A15 regions of the rat brain using double immunofluorescence. The distribution of glutamate receptor 1- or 2/3-like immunoreactive neurons completely overlapped that of tyrosine hydroxylase-like immunoreactive neurons in dopamine cell groups in the retrorubral field (A8), the substantia nigra (A9), the ventral tegmental area and the nucleus raphe linealis (A10), and the rostral hypothalamic periventricular nucleus (A14, A15). In the caudal hypothalamic periventricular nucleus (A11), arcuate nucleus (A12) and zona incerta (A13), the distribution was partially overlapping. Neurons double-labeled for tyrosine hydroxylase and glutamate receptor 1 or 2/3 immunoreactivities were, however, exclusively found in certain dopamine cell regions: in areas A14-A15, 85-88% of tyrosine hydroxylase-containing neurons expressed glutamate receptor 1 and 22-25% expressed glutamate receptor 2/3, while in areas A8-A10, 20-43% expressed glutamate receptor 1 and 63-84% expressed glutamate receptor 2/3. In contrast, the double-labeled neurons were hardly detected in the A11-A13 regions. No tyrosine hydroxylase-positive neurons displayed glutamate receptor 4 immunoreactivity, though a partially overlapping distribution of tyrosine hydroxylase- and glutamate receptor 4-immunopositive neurons was also seen in regions A8-10, A11 and A13. The present study has demonstrated the morphological evidence for direct modulation of dopamine neurons via AMPA receptors in rat mesencephalon and hypothalamus. This distribution may provide the basis for a selective dopamine neuron loss in neurodegenerative disorders, such as Parkinson's disease.

Recognition of adverse and nonadverse effects in toxicity studies

One of the most important quantitative outputs from toxicity studies is identification of the highest exposure level (dose or concentration) that does not cause treatment related effects that could be considered relevant to human health risk assessment. A review of regulatory and other scientific literature and of current practices has revealed a lack of consistency in definition and application of frequently used terms such as No Observed Effect Level (NOEL), No Observed Adverse Effect Level (NOAEL), adverse effect, biologically significant effect, or toxicologically significant effect. Moreover, no coherent criteria were found that could be used to guide consistent interpretation of toxicity studies, including the recognition and differentiation between adverse and nonadverse effects. This presentation will address these issues identified first by proposing a standard set of definitions for key terms such as NOEL and NOAEL that are frequently used to describe the overall outcome of a toxicity study. Second, a coherent framework is outlined that can assist the toxicologist in arriving at consistent study interpretation. This structured process involves two main steps. In the first, the toxicologist must decide whether differences from control values are treatment related or if they are chance deviations. In the second step, only those differences judged to be effects are further evaluated in order to discriminate between those that are adverse and those that are not. For each step, criteria are described that can be used to make consistent judgments. In differentiating an effect from a chance finding, consideration is given inter alia to dose response, spurious measurements in individual parameters, the precision of the measurement under evaluation, ranges of natural variation and the overall biological plausibility of the observation. In discriminating between the adverse and the non-adverse effect consideration is given to: whether the effect is an adaptive response, whether it is transient, the magnitude of the effect, its association with effects in other related endpoints, whether it is a precursor to a more significant effect, whether it has an effect on the overall function of the organism. whether it is a specific effect on an organ or organ system or secondary to general toxicity or whether the effect is a predictable consequence of the experimental model. In interpreting complex studies it is recognised that a weight of the evidence approach, combining the criteria outlined here to reach an overall judgment, is the optimal way of applying the process. It is believed that the use of such a scheme will help to improve the consistency of study interpretation that is the foundation of hazard and risk assessment.

Effects of light intensity, n-alcohols, water-soluble colorants, and solution viscosity on photoisomerization of sorivudine

Effects of various factors, such as light intensity, polarizability of n-alcohol solvents, addition of colorants, and viscosity of solutions on the kinetics of the photoisomerization of therapeutically effective E-isomer of sorivudine to its less effective Z-isomer were studied. Solutions of known concentrations of E-isomer or Z-isomer in water or in a series of n-alcohols were directly exposed to ultraviolet (UV) A light, or visible light of 400 or 900 foot candles (fc). E-isomer solutions containing various colorants at 1% w/v, or in a series of poloxamer solutions of different viscosities, were also exposed to 400 or 900 fc light. Using the stability-indicating HPLC assay, which showed mass-balance between the starting isomer and the converting isomer, the kinetics of photoisomerization were monitored. The photoisomerization reaction, which takes place on the vinyl side chain, was found to be a first-order reversible reaction. In water, the rate of conversion of E-isomer to Z-isomer was faster than that of Z-isomer to E-isomer, since, E-isomer with higher extinction coefficient absorbed substantially more light than Z-isomer. The rate of photoisomerization increased with the intensity of the visible light and was very rapid in the presence of UV A light (300 to 400 nm), which is to be expected based on the 239 nm and 283 nm absorption maxima of sorivudine. Addition of water-soluble colorants retarded the photoisomerization process significantly, especially as the maximum absorption wavelengths (lambda max) of the colorants approached the UV region. The rate of photoisomerization increased with increasing polarizability (alpha s) of the n-alcohol solvents. Polarizable solvents such as alcohols could compensate for the electron density built up in the excited state, and thus facilitated the photoisomerization process. The rate of photoisomerization decreased as the viscosity of solution increased. This may be attributed to the fact that the twisting of the C=C bond in the excited state can be inhibited by the friction imposed by the viscous medium.

[Marine toxins]

The consumption of seafood, which is contaminated by toxines of red tides, is a common cause of disease in tropic regions. The most important diseases, which are caused by red tides are Paralytic Shellfish Poisoning (PSP), Diarrhetic Shellfish Poisoning (DSP), Neurotoxic Shellfish Poisoning (NSP), Amnesic Shellfish Poisoning (ASP), Ciguatera Fish Poisoning (CFP).

[Radiotherapy for basal cell carcinoma. Local control and cosmetic outcome]

BACKGROUND

The basal cell carcinoma which is often occurring in the elderly can be well treated by surgery. For large and recurrent lesions and in cosmetically difficult locations external beam radiotherapy provides an equally effective treatment alternative.

PATIENTS AND METHODS

From 1986 to 1999, 60 females and 39 males received primary radiotherapy for a total of 127 histologically verified basal cell carcinoma lesions. Tumors were mostly localized in the face at the temple, nose and forehead. Radiotherapy was applied with orthovoltage equipment and energies of up to 100 kV. Single doses ranged from 2 to 5 Gy related to the 80%-isodose depth. Weekly doses ranged from 8 to 25 Gy and total doses from 25 to 60 Gy. The mean follow-up period was 36 +/- 21 months. The acute sequelae were scored according to CTC criteria. Radiogenic late effects as single events were related to the radiation portal.

RESULTS

3 months after treatment all besides one patient (99%) experienced complete tumor remission (CR). In all cases, acute radiation reaction occurred within the radiation portal: CTC Grade 1 in 100%, CTC Grade 2 in 54% and CTC Grade 3 in 30% of the cases. All side effects regressed under simple local measures without further complications. Late sequelae were observed in three cases. Overall cosmetic outcome was good to excellent in almost all patients (98%). In two cases (2%) a local recurrence was observed 6 and 20 months after radiotherapy.

CONCLUSION

External beam (orthovoltage) radiotherapy is very effective and yields high tumor control rates and good cosmetic results in long-term follow-up. Former dermatological treatment concepts should be replaced by an ICRU-based radiophysical dose prescription and should respect the newer radiobiological fractionation principles.

Presynaptic neuronal antigens expressed by a small cell lung carcinoma cell line

Small cell lung carcinoma (SCLC) is a tumour of neuroendocrine origin often found in association with autoimmune paraneoplastic neurological disorders. We established a SCLC cell line from a woman with Lambert-Eaton myasthenic syndrome (LEMS) who developed antibodies to both the P/Q-type voltage-gated calcium channels (VGCC) and the muscle acetycholine receptor (AChR). We used a range of techniques to establish which neuronal antigens were expressed in her tumour cell line. The results show that many proteins involved in exocytosis are present in the SCLC cells, and that depolarisation-dependent release of [(3)H]-serotonin is linked to calcium influx through P/Q-type VGCCs. In addition, some of the subunits encoding the AChR and both agrin and ARIA, molecules released from the motor nerve during development, were expressed. These results suggest that many potential antigenic targets are present in SCLC, and indicate a surprising 'motor nerve terminal'-like characteristic of this line.

Long term outcome in Lambert-Eaton myasthenic syndrome without lung cancer

OBJECTIVES

To determine the prognosis in patients with Lambert-Eaton myasthenic syndrome (LEMS) without small cell lung cancer (SCLC), and to analyse longitudinal clinical, electrophysiological, and immunological data on each patient to establish prognostic factors for long term outcome.

METHODS

The retrospective and part prospective study of 47 patients with LEMS was undertaken from data recorded during visits to a specialist neuromuscular clinic. Serial measurements of muscle strength score in shoulder abduction, elbow extension and hip flexion, compound muscle action potential (CMAP) amplitude, and postcontraction increment in abductor digiti minimi (ADM), and anti-P/Q-type voltage gated calcium channel (VGCC) antibody titre were made at each visit.

RESULTS

Muscle strength scores were improved in 88% of patients after a median duration of immunosuppressive treatment of 6 years (range 1.3 to 17 years); anti-VGCC antibody titres fell in 52% after treatment; and mean resting CMAP amplitude improved from 2.7 mV initially to 8.8 mV after 2 years of treatment p<0.001). Initial pretreatment anti-VGCC antibody titre did not correlate significantly with either CMAP amplitude, CMAP increment, or clinical score: from serial measurements made during follow up, significant correlation between antibody titre and CMAP amplitude was seen in only two patients. Sustained clinical remission was achieved by 20 (43%) of whom only four remained in remission without the need for immunosuppression. Using a Cox proportional hazards model, the only independent predictor of sustained clinical remission was initial pretreatment clinical score (p=0.03). Lymphoma presented in three patients during the study.

CONCLUSIONS

The prognosis in patients with LEMS without SCLC is favourable, although patients often need significant doses of immunosuppressive treatment to remain clinically stable. Only initial clinical muscle strength measurements and not anti-VGCC antibody titres or electrophysiological recordings are predictive of long term outcome.

Molecular targets for autoimmune and genetic disorders of neuromuscular transmission

The neuromuscular junction is the target of a variety of autoimmune, neurotoxic and genetic disorders, most of which result in muscle weakness. Most of the diseases, and many neurotoxins, target the ion channels that are essential for neuromuscular transmission. Myasthenia gravis is an acquired autoimmune disease caused in the majority of patients by antibodies to the acetylcholine receptor, a ligand-gated ion channel. The antibodies lead to loss of acetylcholine receptor, reduced efficiency of neuromuscular transmission and muscle weakness and fatigue. Placental transfer of these antibodies in women with myasthenia can cause fetal or neonatal weakness and occasionally severe deformities. Lambert Eaton myasthenic syndrome and acquired neuromyotonia are caused by antibodies to voltage-gated calcium or potassium channels, respectively. In the rare acquired neuromyotonia, reduced repolarization of the nerve terminal leads to spontaneous and repetitive muscle activity. In each of these disorders, the antibodies are detected by immunoprecipitation of the relevant ion channel labelled with radioactive neurotoxins. Genetic disorders of neuromuscular transmission are due mainly to mutations in the genes for the acetylcholine receptor. These conditions show recessive or dominant inheritance and result in either loss of receptors or altered kinetics of acetylcholine receptor channel properties. Study of these conditions has greatly increased our understanding of synaptic function and of disease aetiology.

Peptide neurotoxins, small-cell lung carcinoma andneurological paraneoplastic syndromes

Peptide neurotoxins isolated from the venom of snakes, spiders and snails have represented invaluable tools for the identification and characterisation of membrane ion channels and receptors in vertebrate cells, including human neurons. We here report on the use of these toxins for the characterisation of membrane ion channels and receptors expressed by one of the most aggressive human cancers, small-cell lung carcinoma. This tumour shares many properties with other neuro-endocrine cell types, including the ability of firing action potentials and release hormones in a calcium-dependent manner. Toxins such as alpha-bungarotoxin and omega-conotoxins, among others, have been successfully used to characterise neuronal nicotinic receptors and voltage-dependent calcium channels, respectively, in human small-cell lung carcinoma cells. These receptors and ion channels are not only crucial for the growth of this specific tumour, but also represent autoantigens against which cancer patients build an autoimmune response. Although the aim of this autoimmune response is eventually the destruction of the cancer cells, the circulating antibodies cross-react with similar ion channels and receptors present in normal neurons or other cells, causing a number of different paraneoplastic diseases, the best characterised of which is the Lambert-Eaton myasthenic syndrome. Conotoxin-based radioimmunoassays have become an invaluable tool for the diagnosis and follow up of these paraneoplastic disorders and could represent a step forward in the early diagnosis of small-cell lung carcinoma itself.

Autoantibody screening in subacute cerebellar ataxia

In a retrospective study of 280 sera from patients presenting with cerebellar signs, seven of whom had proved positive for the typical paraneoplastic serum antibodies that were requested by the clinicians, raised concentrations of antibodies to voltage-gated calcium channels or to glutamic acid decarboxylase were detected in a further seven sera. Systematic screening for these and other antibodies in future cases should help in the diagnosis and management of the patients.

Serotonin potentiates the response of neurons of the superficial laminae of the rat spinal dorsal horn to gamma-aminobutyric acid

Employing the Nystatin-perforated whole-cell patch-clamp recording technique, the modulatory effects of serotonin (5-HT) on gamma-aminobutyric acid (GABA)-activated whole-cell currents were investigated in neurons acutely dissociated from the superficial laminae (laminae I and II) of the rat spinal dorsal horn. The results showed: (1) GABA acted on GABA(A) receptors and elicited inward Cl(-) currents (I(GABA)) at a holding potential (V(H)) of -40 mV; (2) 5-HT potentiated GABA-induced Cl(-) current without affecting the reversal potential of I(GABA) and the apparent affinity of GABA to its receptor; (3) alpha-methyl-5-HT, a selective agonist of 5-HT(2) receptor, mimicked the potentiation effect of 5-HT on I(GABA), whereas ketanserine, an antagonist of 5-HT(2) receptor, blocked the potentiation effect of 5-HT; (4) Chelerythrine, an inhibitor of protein kinase C, reduced the potentiation effect of 5-HT on I(GABA). The present results indicate: (1) The potentiation of 5-HT on I(GABA) is mediated by 5-HT(2) receptor and through a protein kinase-dependent transduction pathway; (2) The interactions between 5-HT and GABA might play an important role in the modulation of nociceptive information transmission at spinal cord level.

Pneumocystis carinii pneumonia as a complication of immunosuppressive therapy

BACKGROUND

Patients receiving immunosuppressive therapy with corticosteroids and cytotoxic agents may develop opportunistic infections such as Pneumocystis carinii pneumonia (PCP). This indicates a severe T-cell defect, but so far there are no established criteria for identifying patients at risk.

PATIENTS AND METHODS

CD4+ and CD8+ T-lymphocyte counts were determined by flow cytometry in seven HIV-negative patients who developed PCP as a complication of immunosuppressive treatment.

RESULTS

CD4+ T-lymphocyte counts (T-helper phenotype) were less than 200/microl in all seven patients (mean 90.6/microl). The markedly reduced CD4 counts measured in these patients are similar to those observed in organ transplant recipients who developed PCP during immunosuppressive therapy for prevention of graft rejection and in HIV-positive patients with PCP as an AIDS-defining illness.

CONCLUSION

Measuring CD4+ T-lymphocyte counts may be helpful in determining the risk of PCP not only in HIV-positive patients, but also in patients receiving immunosuppressive therapy. The risk of acquiring PCP seems to increase when CD4+ lymphocyte counts drop below 200/microl, regardless of the underlying disease.

The adrenal steroid status in relation to inflammatory cytokines (interleukin-6 and tumour necrosis factor) in polymyalgia rheumatica

OBJECTIVES

To determine the correlation between inflammatory cytokines and adrenal hormones in patients with polymyalgia rheumatica (PMR) and to compare the ratio of serum cortisol and androstenedione (ASD) or dehydroepiandrosterone sulphate (DHEAS) in normal subjects with PMR patients.

METHODS

In 102 patients with PMR (32 beginning and 70 chronic disease) and 31 age-matched and sex-matched healthy subjects, ASD, cortisol, DHEAS, interleukin-6 (IL-6), and tumour necrosis factor (TNF) were measured by immunometric assays.

RESULTS

Serum levels of IL-6 were elevated in patients with PMR as compared with normal subjects (10.0 +/- 1.6 vs 2.1 +/- 0.1 pg/ml, P = 0.01), which was not found for TNF. In PMR patients, serum levels of IL-6 were positively correlated with serum levels of ASD (P < 0.001), cortisol (P < 0.001), and DHEAS (P = 0. 038) irrespective of corticosteroid treatment. Serum levels of cortisol in relation to IL-6 were significantly lower in patients with chronic disease and long-standing corticosteroid administration as compared with patients with recent onset of the disease and without corticosteroid therapy (P < 0.01).

CONCLUSIONS

In PMR, as expected, there was an increase in IL-6 serum levels that was associated with elevated serum levels of ASD, DHEAS, and cortisol which was more marked in patients with recent-onset disease and without corticosteroids. However, serum levels of cortisol in patients with and without corticosteroids were lower than expected by considering the inflammatory status (increased IL-6). This may indicate a change in the hypothalamic-pituitary-adrenal (HPA) axis responsiveness to inflammatory stimuli such as IL-6 during chronic disease. Furthermore, there seems to be a shift of biosynthesis to cortisol in relation to DHEAS or ASD in chronic disease.

Call us first--we'll fix it. How a day case unit plays a vital role through teamwork

Clinical effectiveness can be defined as 'the extent to which specific clinical interventions, when deployed in the field for a particular patient or population, do what they are intended to do ... maintain health and secure the greatest possible health gain from the available resources.' (NHS Executive 1996) 3M/NATN Award winner for 1999 Bobbie Lang describes how her Day Case Unit has become the central focus for the co-ordination of such procedures--offering clinical effectiveness for a particular patient group.