Immunohistochemical approach to the pathogenesis of bovine spongiform encephalopathy in its early stages

An immunohistochemical and histochemical study was carried out on the brains of nine cases of BSE-diagnosed cattle as part of the surveillance plan in Catalonia, Spain. The animals had no clinical symptoms reported and were thus at early stages of the disease. The first part of the study consisted of a characterization of PrP(BSE) deposits throughout the encephalon. The behaviour of the different immuno-labelling patterns was analysed and tropism of some patterns towards certain brain areas was described. This tropism is principally directed to the brain stem region; however, an association of the stellate pattern was found with areas where PrP(BSE) is deposited less abundantly, such as the cerebral cortex. Secondly, distinct pathogenesis mechanisms that take place in the early stages of BSE, which would include these cases were investigated. This study describes the glial response to the presence of PrP(BSE) (using antibodies against astrocytic glial fibrillary acidic protein and lectin from Griffonia simplicifolia to identify microglia), the presence of mild oxidative stress phenomena (antibodies against metallothioneins I and II and against nitrated aminoacidic residues: nitrotyrosine), the apparent absence of apoptotic cellular death (cleaved caspase 3) and the preservation of synaptic proteins synaptophysin and small synaptosome-associated 25 kDa protein immuno-labelling. Finally, no alteration of the extra-cellular matrix was detected with the use of Wisteria floribunda agglutinin, a marker for perineuronal nets.

[Adverse drug related events in a postemergency unit: prospective cohort study with 6 months follow up]

PURPOSE

To analyse iatrogenic events in elderly people and determine the part of unplanned admission in postemergency units directly related to thus iatrogenic events.

METHODS

The authors conducted a prospective chart review on treatments and potentials adverse drug-related events of all elderly consecutively hospitalized between January and Marsh 2003 in a postemergency department. A 6 months prospective evaluation after discharge was made for all elderly with adverse drug-related event.

RESULTS

One hundred (and) eighty-six elderly (mean age 83+/-5.7 years) were prospectively included. Eighty-one per cent are ambulatory with a self-medication administration in spite of a real disability (activity of daily-living: 4.5+/-1.8). The number of medications consumed ranged from 0 to 15 and averaged 6, with to different source of prescriptions in 34% of the cases. The treatment was recently modified in 41 cases (22%). Adverse drug related events accounted in 55 cases (29%) and hospitalization was directly related to iatrogenic event in 32 cases (17%). Adverse drug related events could be avoided in half cases. There was no death directly related with adverse drug reactions. Follow up after discharge was obtained in 47 cases and pointed out elderly disability: 34 were again hospitalized, 14 admitted in nursing home facilities and 12 died. Treatment was equivalent to our prescription only in 35% of the cases; on the other hand, we found only four elderly with medication directly related to previous adverse event.

DISCUSSION

Theses results pointed out once again polymedication observed in frail elderly people leading to extreme difficulty to prescription due to polypathology. Prescription renewal could be related to adverse drug related events and precipitated elderly people in disability leading to institutionalization.

Head-and-neck swelling: an under-recognized feature of giant cell arteritis. A report of 37 patients

OBJECTIVE

To describe the frequency of occurrence and characteristics of head-and-neck swelling (HNS) in temporal (giant cell) arteritis (TA).

METHODS

We analyzed the charts of patients with HNS retrieved from a single department series of 260 consecutive patients with TA and reviewed the published French-English literature. Patients with a swelling limited to the temporal fossa were excluded.

RESULTS

A history of HNS was elicited in 17 patients in our series (i.e. 6.5%) and in 20 previously published patients. The swelling was an inaugural feature in most cases and was often transient. Ear-nose-and-throat (ENT )symptoms were observed in 80% of the cases, including jaw claudication or pain upon opening mouth in 22, causing trismus in 10. Two patients had permanent visual impairment and 1 had sudden hearing loss. The temporal artery biopsy yielded giant cell arteritis (GCA) in all the patients but 2. The HNS was often painful and mainly involved mainly the orbital region and face, particularly the lower part of the cheeks and maxillae, less often the neck and, rarely, the forehead and tongue. Concurrent localized limb swellings were also observed in 3 patients. The HNS disappeared in all the patients, either spontaneously or under steroid treatment, and recurred only in 6 patients.

CONCLUSION

HNS is not exceptional in untreated TA and is strongly associated with ENT symptoms and a positive TAB, but not with visual loss or stroke. Such characteristics imply in these cases a prominent, widespread involvement of the external carotid artery system by giant cell arteritis.

Neuronal intranuclear inclusion disease in a horse

Neuronal intranuclear inclusion disease (NIID) is reported in a 16-year-old Pure Spanish breed female horse suffering from progressive ataxia and motor deficiencies. The neuropathological study revealed NIIs throughout the central nervous system, although mainly in the brain stem and spinal cord. This distribution did not correlate with neuron loss, which was marked in the hippocampus and moderate in the neocortex, particularly in the occipital cortex. As in humans, NIIs in the horse were hyaline autofluorescent inclusions composed of non-membrane-bound aggregates of filaments and fine granules. NIIs were stained with anti-ubiquitin and anti-clusterin antibodies. In addition, NIIs were stained with antibodies raised against subunits of the 19S and PA28, but not of the 20S, components of the proteasome. These observations indicate similarities between NIID in humans and horses, and suggest that clusterin and abnormal ubiquitin-proteasomal expression participate in NII formation.

Orbital Meningioma with a Granular Cell Component in a Dog, with Extracranial Metastasis

A meningioma with a significant component of granular cells is described in the left ocular orbit of a 5-year-old male Golden retriever dog that presented with exophthalmos. The neoplastic mass surrounded the optic nerve. Microscopically, the tumour was characterized by nests of large, round to polygonal cells, variable in size, with eccentric nuclei and abundant eosinophilic cytoplasm, containing PAS-positive granules. In focal areas, cells were smaller and occasionally formed whorl-like structures. Immunohistochemical analysis revealed that neoplastic cells reacted positively for vimentin and, with less intensity, for neuron specific enolase and S-100, whereas they were negative for glial fibrillary acidic protein and cytokeratins. Metastatic growths, formed by similar cells, were seen in the lung and heart.

Maladie de Horton et plexite brachiale C5–C6 : une observation avec revue de la littérature

BACKGROUND

Shoulder palsy due to brachial plexopathy (or lower cervical radiculopathy) is a rare occurrence in patients with giant cell temporal arteritis (TA). We report a patient with C5 plexopathy revealing TA, with review of the literature.

EXEGESIS

A 67-year-old woman presented with a complex neurological syndrome of rapid onset, including a left trigeminal neuralgia, painless masticatory palsy, impaired swallowing, and severe palsy of the left shoulder, corresponding to a C5 plexitis. Giant cell arteritis was suspected on clinical and laboratory grounds and was documented on temporal artery biopsy. Treatment with pulse methylprednisolone (100 mg every 8 hours for three days), followed by prednisone (1 mg/kg daily), resulted in progressive improvement of the neurological deficits, full shoulder strength being recovered within 6 months. An extensive world literature allowed us to review 23 other cases of TA complicated by either lower cervical radiculopathy or C5 brachial plexopathy. These peripheral neuropathic manifestations occurred sometimes bilaterally and were isolated or, less often, part of a mononeuritis multiplex. Involved patients were relatively young (mean age 67 years) and 54% were men. The pathophysiology of TA-associated C5 radiculopathy or brachial plexitis is still poorly understood. Fortunately, functional prognosis was consistently good with corticosteroid treatment.

CONCLUSION

Giant cell arteritis should always be considered in elderly or middle-aged patients presenting with C5 radiculopathy or plexopathy and elevated inflammatory markers.

[Evolution of Sjögren syndrome associated with hepatitis C virus when chronic hepatitis C is treated by interferon or the association of interferon and ribavirin]

Hepatitis C virus is one of the most likely candidates as a potential pathogenic agent causing Sjogren's syndrome (SS) in a subset of patients. Nobody has until now described the evolution of SS associated with HCV when chronic hepatitis C is treated with antiviral therapy, interferon being an auto-immunity inductor. This is the purpose of our study.

METHODS

Prospective study of 12 patients with a HCV-associated SS defined as certain according to the first european criteria and treated with interferon or interferon/ribavirin for their chronic hepatitis C.

RESULTS

More than fifty percent of these patients developed a severe immunological complication especially when they were treated with interferon alone. Ribavirin may have had a protective role on interferon-mediated immunological complications. These complications went on after cessation of therapy. Sicca syndrome was improved only in the patients treated with the association (in 50% of the cases), but these patients also had a sustained virological response. It is difficult to tell if this improvement was due to the hepatitis C virus eradication or ribavirin treatment.

CONCLUSION

Hepatitis C virus is implicated in the development of SS in a specific subset of patients for which we can propose the term SS "secondary to HCV" and this disease is not utterly benign especially after the introduction of interferon therapy. Ribavirin when associated with interferon gives a significative sustained virological response and could lower the incidence of immunological interferon-mediated complications with a favorable outcome of sicca syndrome.

Comparative study of the PrPBSE distribution in brains from BSE field cases using rapid tests

The distribution of PrP(BSE) in the brain of nine confirmed BSE field cases was analyzed using immunohistochemistry and compared to the levels of PrP(BSE) determined by two rapid tests (Prionics-Check WESTERN and Prionics-Check LIA). Each brain was dissected into 16 areas: spinal cord, medulla oblongata, pons, mesencephalon, thalamus, hippocampus, cerebellar vermis, cerebellar medulla, cerebellar hemispheres, occipital cortex, temporal cortex, parietal cortex, striatum, frontal cortex, piriform lobe and olfactory bulbs. The highest levels of PrP(BSE) were detected in the medulla oblongata, spinal cord and pons, and correspondingly both rapid tests showed 100% correlation with the immunohistochemistry with regard to sensitivity and specificity. Some inconsistencies between the levels of PrP(BSE) determined either by immunohistochemistry or by the rapid tests were found in brain areas with medium to low levels of PrP(BSE). These brain areas included the cerebellar hemisphere, olfactory bulb, and the temporal and parietal cortices. A brain PrP(BSE) distribution curve (BPDC) was designed by plotting the PrP(BSE) signals obtained from the two rapid tests versus the anatomical region along the caudal-rostral axis of the brain. Comparison of the BPDC of the nine BSE cases showed that all cases had a similar PrP(BSE) distribution in the brain but with variable intensities, which could be explained by different stages in the progression of the disease. We propose that the BPDC could be used as a tool to differentiate classical cases of BSE from the recently identified atypical BSE cases.

Intensification thérapeutique et autogreffe de cellules souches hématopoïétiques pour le traitement des maladies auto-immunes

THE PATHOPHYSIOLOGY of most autoimmune diseases is often poorly understood. EXPERIMENTAL CONSIDERATIONS and clinical experience suggest that high doses immunoablation followed by stem cell transplantation is a therapeutic option to consider for certain severe autoimmune disorders. THE CONCEPT OF RESTORING NORMAL IMMUNE REACTIVITY must in part br true since current results of 466 transplants (445 autologous, 21 allogeneic) patients suffering from various autoimmune diseases show a beneficial outcome in approximately 2/3 of the patients. TO IMPROVE THE EFFICACY AND SAFETY OF SUCH AN AGGRESSIVE PROCEDURE in patients with potentially affected vital organs by the underlying autoimmune disease, it is especially important to follow international consensus guidelines and to centrally collect clinical data for in depth analysis in the EBMT International Stem Cell Project for Autoimmune Disease in Basel, Switzerland. PHASE III STUDIES ARE RUNNING FOR SYSTEMIC SCLEROSIS (Astis, Autologous Stem cell Transplantation International Rheumatoid Arthritis Trial) started in 2003. A STUDY PROJECT IS PLANNED FOR MULTIPLE SCLEROSIS (Astims, Autologous Stem cell Transplantation International Multiple Sclerosis).

Maladie de Horton : associations morbides chez 250 malades

INTRODUCTION

Miscellaneous disorders have been described in association with temporal (giant cell) arteritis (TA), most often anecdotally, except with arteriosclerosis.

METHOD

In a retrospective study, we reported our personal experience of disease associations in a series of 250 patients diagnosed with TA and followed-up in the department between 1976 and 2003.

RESULTS

Disease associations were found in 43 patients, i.e. 17% of cases: concurrent malignancy (23 patients: 17 cancers and 6 blood diseases), primary Gougerot-Sjögren's syndrome (6 cases), endocrine disease other than Hashimoto's thyroiditis (7 cases: 3 hyperparathyroidism [HPP], 3 hyperthyroidism, 1 association HPP + hyperthyroidism), polyneuropathy (3 cases), essential thrombocythaemia (2 cases), anti-neutrophilic cytoplasmic (anti-myeloperoxidase) antibodies (2 cases), and miscellaneous associations (1 case of RS3PE syndrome, nephrotic syndrome, myasthenia, sarcoidosis, and macro-creatine kinase type 2). More than one disease associated was present 5 patients. In 77% of the patients, there was a strong temporal association between TA and the alternate illness. No systemic necrotizing vasculitis or rheumatoid arthritis was observed in any patient.

CONCLUSION

In our experience, there was a frequent, non-fortuitous, association between TA and malignancy. Auto-immune conditions were rare, but the prevalence of Gougerot-Sjögren's syndrome might have been underestimated. Hyperthyroidism and HPP are not exceptional and must be recognised in order to avoid severe bone loss induced by corticosteroids.

A Novel Spongiform Degeneration of the Grey Matter in the Brain of a Kitten

A young female domestic short-hair cat presented with neurological signs consistent with a multifocal encephalic lesion (depressed mental status, head tilt to the right, cervical ventroflexion, head tremors, tetraparesis, conscious propioceptive deficits in all four limbs and visual deficits). No gross lesions were seen at necropsy. On light microscopical examination lesions were found only in the brain and cervical spinal cord. A generalized vacuolation of the grey matter of the brain was observed. Special staining techniques, immunohistochemistry, lectin affinity histochemistry and ultrastructural studies were performed to characterize the lesion; preservation of the white matter and a reactive astrogliosis were demonstrated. Feline retroviruses and PrPsc were not detected. Ultrastructurally, a dilatation of intracytoplasmic membrane-bounded organelles with membrane disruption and dendritic and somatic swelling was found in astrocytes and neurons. The age of the animal and histological changes suggested a novel, possibly congenital, spongiform degeneration of the brain and cervical spinal cord.

New concepts in cyclosporine pharmacokinetic and dynamic monitoring: the impact of concomitant immunosuppression on target C2 concentrations

BACKGROUND

There is a correlation between cyclosporine (CsA) pharmacokinetics (PK) and pharmacodynamics (PD), especially 2 hours after drug administration.

AIM

To evaluate the relationship between CsA PK and PD profiles in two groups of stable renal transplant patients treated with CsA alone or CsA plus mycophenolate mofetil (CsA+MMF), so as to define the best target for C2 and clarify the impact of concomitant immunosuppression.

METHODS

Thirty-eight stable renal transplant recipients were treated with CsA (n=20) or CsA+MMF (n=18). Twelve nontreated normal healthy controls (NHC) were also included. Calcineurin activity (CNa), IL-2 production, and CsA levels were measured at 0 and 2 hours postdose.

RESULTS

There were no significant differences in median CsA C2 values and CNa between the CsA alone and the CsA+MMF groups (388 microg/L and 497.5 microg/L and CNa 2h; 3.92% alkaline phosphatase [AP]; 3.94% AP, respectively). In vitro production of IL-2 was significantly lower in the CsA+MMF group than in the CsA group (median IL-2 2h: 280.52 ng/L, 169.48 ng/L, P<.001). The correlations (r) between C2 and CNa 2h were: CsA r=0.74; CsA+MMF r=0.84 (P<.001 in both cases).

CONCLUSIONS

In stable renal transplant patients, median CsA C2 values below 500 microg/L were associated with inhibition of CNa and IL-2 synthesis. CNa and IL-2 production may be good biological markers of CsA immunosuppression. The measurement of CNa depends mainly on CsA concentration, whereas in vitro IL-2 production reflects the effect of both CsA and MMF. Further studies are necessary to define the optimal C2 target concentration and the possible impact of concomitant immunosuppression.

Pharmacokinetic and pharmacodynamic correlations of cyclosporine therapy in stable renal transplant patients: evaluation of long-term target C(2)

We investigated the relationship between the pharmacokinetics and pharmacodynamics of cyclosporine in 15 stable renal transplant patients in order to define an effective and safe therapeutic range. The area under the curve of the first 4 h (AUC(0-4)), trough (C(0)) and 2 h (C(2)) levels showed median values of 1655 ng x h/ml, 114 ng/ml and 384 ng/ml, respectively. C(2) showed a strong correlation with AUC(0-4) (r=0.942, p=0.0005). C(0) correlated poorly with C(2) and AUC(0-4) (r=0.596, p=0.019 and r=0.538, p=0.031, respectively). Calcineurine activity (CNa) was 6.74% at 0 h and 3.90% at 2 h, representing significant reductions (82% and 89.6%, respectively; p<0.0005) compared with normal healthy controls (median basal value 37.4%). IL-2 production was 349 pg/ml at 0 h and 276.35 pg/ml at 2 h; both results were significantly lower (reductions of 44.5% and 56.1%, respectively; p=0.04 and 0.005) than the controls of 629.1 pg/ml. IFN-gamma at 2 h post-dose (8.16 UI/ml) was significantly lower (72.1% reduction, p=0.005) than in controls (29.2 UI/ml). There was a good correlation between CNa and IFN-gamma production, particularly at 2 h post-dose (r=0.537, p=0.007), and a fair correlation between CNa and IL-2 concentration (p=0.030, r=0.426). C(2) showed an inverse significant correlation with CNa (Spearman's p=0.000, r=-0.753), IL-2 (p=0.000, r=-0.725) and IFN-gamma (p=0.000, r=-0.701) production. In treated patients, the Emax inhibitory sigmoidal model showed that a C(2) of 279 ng/ml was needed to achieve a 50% inhibition (EC50) of IL-2 and INF-gamma production. The results demonstrated a significant inhibition of calcineurin activity and IL-2 and IFN-gamma production in patients receiving cyclosporine monotherapy compared to healthy controls. A median C(2) value of 384 ng/ml was associated with a good degree of inhibition of CNa and IL-2 and IFN-gamma synthesis, and the lack of rejection episodes and relevant toxicity.

[Dysmetabolic hepatosiderosis, characteristics in 51 patients]

OBJECTIVE

Dysmetabolic hepatosiderosis is a recently described entity, which reunites iron overloads associated with polymetabolic syndromes, steatosis and steato-hepatitis. The aim of this study was to specify the relationship between iron overload, polymetabolic syndrome, HFE mutations of primary hemochromatosis and steatosis.

METHOD

This was a 5-year retrospective study of 51 patients hospitalised and/or seen in consultation, non-alcoholic, presenting with hyperferritinemia associated with a polymetabolic syndrome and/or hepatic steatosis.

RESULTS

Patients mean age was of 53 +/- 12 years with a sex ratio M/F of 5.4. Metabolic disorders were found in 97% of the non-steatosis patients (overweight: 40%, perturbed sugar metabolism: 47%, dyslipidemia: 79.5%). Hyperferritinemia was constant but moderate (513.4 +/- 280.3 ng/ml). Transferrin saturation was predominantly normal (0.44 +/- 0.17). The hepatic enzymes were normal or only slightly perturbed. Steatosis was revealed by sonography in 62% of cases. The hepatic iron overload, documented in 6 patients by hepatic needle biopsy, was discreet (concentration/age ratio of 1.64 +/- 0.19). Among the 59% patients screened for the HFE gene, 40% were positive for C282Y and/or H63D. There was no correlation between ferritin levels and iron parameters, polymetabolic syndrome parameters and hepatic enzymes. The HFE mutations had no influence on the iron parameters.

CONCLUSION

Dysmetabolic hepatosiderosis must be know by hospital practitioners because of their prevalence in cases of hyperferritinemia and their therapeutic incidence.

Abnormal neuronal expression of the calcium-binding proteins, parvalbumin and calbindin D-28k, in aged dogs

Disturbances of the gamma-aminobutyric acid (GABA) neurotransmitter system have been implicated in chronic degenerative neurological disease. Cognitive dysfunction and neuron loss are features in older dogs. GABAergic neurons also show immunoreactivity for specific calcium-binding proteins. Immunohistochemistry was used to study the neuronal expression of calbindin D-28k and parvalbumin in different areas of the brain in 13 dogs, aged between 2 and 13.5 years. Calbindin expression was found only in the cerebellum. There were significant differences in the quantity and distribution of neurons expressing these proteins between geriatric and adult brains. Parvalbumin- and calbindin-expressing neurons are relatively sensitive to degeneration in the cerebellum of older dogs. Parvalbumin labelling was associated with dystrophic structures that are commonly associated with ageing.

[Systemic lupus erythematosus and herpes virus infection: three new observations]

INTRODUCTION

Systemic lupus erythematosus is still of unknown origin. Viruses have long been postulated to play a role in its pathogenesis particularly cytomegalovirus and Epstein-Barr virus.

EXEGESE

We describe three patients who presented acute onset of systémic lupus erythematosus concurrently with recent viral infection (two with cytomegalovirus and one with Epstein-Barr virus).

CONCLUSION

The peculiar clinical events emphasize the difficulty of diagnosis at the onset of the disease and suggest possible role of these viruses in the pathogenesis of SLE.

Abnormal synaptic protein expression and cell death in murine scrapie

Reduced expression of synaptophysin p38, synaptic-associated protein of molecular weight 25,000 (SNAP-25), syntaxin-1, synapsin-1, and alpha- and beta-synuclein, matching the distribution of spongiform degeneration, was found in the neurological phase of scrapie-infected mice. In addition, synaptophysin and SNAP-25 were accumulated in isolated neurons, mainly in the thalamus, midbrain and pons, and granular deposits of alpha- and beta-synuclein were present in the neuropil of the same areas. No modifications in the steady state levels of Bcl-2, Bax, Fas and Fas ligand were observed following infection. Yet antibodies against the c-Jun N-terminal peptide, which cross-react with products emerging after caspase-mediate proteolysis, recognize coarse granular deposits in the cytoplasm of reactive microglia. In situ end-labeling of nuclear DNA fragmentation showed positive nuclei with extreme chromatin condensation in the thalamus, pons, hippocampus and, in particular, the granular layer of the cerebellum. More importantly, expression of cleaved caspase-3, a major executioner of apoptosis, was seen in a few cells in the same regions, thus indicating that cell death by apoptosis in scrapie-infected mice is associated with caspase-3 activation. The present findings support the concept that synaptic pathology is a major substrate of neurological impairment and that caspase-3 activation may play a pivotal role in apoptosis in experimental scrapie. However, there is no correlation between decreased synaptic protein expression and caspase-3-associated apoptosis, which suggests that in addition to abnormal prion protein deposition, there may be other factors that distinctively influence synaptic vulnerability and cell death in murine scrapie.

Fluorescent monitoring of kinase activity in real time: development of a robust fluorescence-based assay for Abl tyrosine kinase activity

Fluorescent biosensors hold great promise for drug discovery. Using a solid-phase version of protein semi-synthesis, we incorporated two fluorophores at specific sites within a truncated version of the c-Crk-II protein. The resulting fluorescent protein biosensor permits the real-time monitoring of Abl kinase activity and provides a robust and rapid method for assaying Abl kinase inhibitors.