Motor end-plate analysis to diagnose immune-mediated myasthenia gravis in seronegative patients

This study aimed to evaluate the diagnostic usefulness of motor end-plate (MEP) analysis along with clustered acetylcholine receptor (AChR) antibody (Ab) assays in patients with myasthenia-like symptoms but negative routine AChR and muscle-specific kinase (MuSK) Ab tests. MEP analysis of muscle biopsies of the biceps brachii was performed in 20 patients to try to differentiate between those with or without immune-mediated myasthenia gravis (MG). Using a quantitative method, complement C3 deposition and AChR densities in MEPs were examined. Independently, cell-based assays were used to detect serum clustered-AChR Abs. Only five of 20 patients had complement deposition at MEPs; four of these patients had reduced AChR densities similar to those in patients with typical AChR Ab positive MG, and distinct from those in the remaining 15 patients. Two of the four serum samples from these patients had clustered-AChR Abs. All complement-positive patients were considered as having immune-mediated MG and improved with appropriate treatments; although one patient presented with MG 3 years later, the remaining patients had other diagnoses during over 10 years of follow-up. These results suggest the usefulness of MEP analysis of muscle biopsies in diagnosing immune-mediated MG in seronegative patients with myasthenia-like symptoms but, due to the invasiveness of the muscle biopsy procedure, clustered AChR Abs should, if possible, be tested first.

The Usefulness of Functional Near-Infrared Spectroscopy for the Assessment of Post-Stroke Depression

Background: Post-stroke depression (PSD) is the most common mood disorder following stroke and is also the main factor that limits the recovery and rehabilitation of patients with stroke. The prevalence of PSD is ~30%. Since there is no gold standard for the diagnosis and evaluation of PSD, it is important to raise awareness of PSD and to establish methods for its evaluation, early diagnosis, and treatment. In the field of psychiatry, functional near-infrared spectroscopy (fNIRS) has been used as a diagnostic tool for the measurement of oxygenated hemoglobin (oxy-Hb). This study aimed to assess whether fNIRS could be applied in the diagnosis and evaluation of PSD.

Methods: We recruited 45 patients with stroke, who were admitted to Nagasaki Kita Hospital between May 2015 and April 2019. The 17-item Hamilton Rating Scale for Depression (HAMD17), which is considered to be a useful screening and evaluation tool for PSD, was used for the assessment of patients after stroke; moreover, oxy-Hb was measured in the pre-frontal cortex. The subjects were divided into two groups: the depressed group (n = 13) and the non-depressed group (n = 32). We evaluated the correlation between the oxy-Hb integral values and HAMD17 scores.

Results: We investigated the relationship between the oxy-Hb integral values and HAMD17 total scores, and found a negative correlation between them (ρ = −0.331, P < 0.005). There was a significant difference in the oxy-Hb integral values during the activation task period between the depressed and non-depressed groups (3.16 ± 2.7 and 1.71 ± 2.4, respectively; P = 0.040). The results indicated that the patients of the depressed group showed lower oxy-Hb integral values and lower activation in the frontal lobe in comparison with the patients of the non-depressed group.

Conclusion: The present study highlights that the measurement of oxy-Hb by using fNIRS is a useful methodology for the diagnosis of PSD in patients after stroke.

Intentional Supernumerary Motor Phantom Limb after Right Cerebral Stroke: A Case Report

A 47-year-old right-handed man was admitted to our hospital for rehabilitation after right basal ganglion hematoma. On day 57, he noticed a supernumerary motor phantom limb (SPL) involving his right arm, originating at the level of the elbow. The most notable finding of his SPL was the motor characteristic. When the subject had the intention to move the upper paralyzed limb simultaneously with the trainer's facilitating action, he said "there is another arm." The intention to move the paralyzed arm alone or passive movement of the paralyzed arm did not induce the SPL. He showed a severe left sensorimotor impairment and mild hemineglect, but no neglect syndromes of the body (e.g., asomatognosia, somatoparaphrenia, personification and misoplegia, or anosognosia) were observed. Brain MRI demonstrated a hematoma in the right temporal lobe subcortex, subfrontal cortex, putamen, internal capsule, and thalamus. Single-photon emission computed tomography images showed more widespread hypoperfusion in the right hemisphere in comparison to the lesions on MRI. However, the premotor cortex was preserved. Our case is different from Staub's case in that SPL was not induced by the intention to move the paralyzed limb alone; rather, it was induced when the patient intended to move the paralyzed limb with a trainer's simultaneous facilitating action. The SPL may reflect that an abnormal closed-loop function of the thalamocortical system underlies the phantom phenomenon. However, despite the severe motor and sensory impairment, the afferent pathway from the periphery to the premotor cortex may have been partially preserved, and this may have been related to the induction of SPL.

Proposing a new short screening test for upper limb apraxia

Background

Apraxia has a major impact on activities of daily living in stroke patients. The proper assessment and treatment of apraxia is important for maintaining a good quality of life. We developed a short evaluation test for upper limb apraxia.

Patients and Methods

The present Screening Test of Gestures for Stroke consists of 10 items for each verbal instruction and imitation. Each item includes three meaningless gestures, three meaningful gestures and four pantomimes. The Screening Test of Gestures for Stroke is scored based on a 3-point system: 10, 5 or 0 (maximum score: 200). The test took approximately 2–5 min to complete. We recruited 65 patients admitted to our hospital with left hemisphere stroke and 50 healthy subjects.

Results

The reliability of the Screening Test of Gestures for Stroke was as follows: the intraclass correlation coefficient of intra-rater reliability was 0.93 for both verbal instructions and imitations, and the intraclass correlation coefficient total scores for inter-rater reliability for verbal instructions and for imitations were 0.97 and 0.95, respectively. The alpha coefficient was ≥0.80.

Conclusions

The Screening Test of Gestures for Stroke is a reliable and valid bedside test that has a short assessment time, does not require special equipment and can evaluate upper limb apraxia in stroke patients from the acute to the chronic phase.

Pure Amorphagnosia without Tactile Object Agnosia

A 54-year-old female showed amorphagnosia without ahylognosia and tactile agnosia 40 days after the onset of right cerebral infarction. Her basic somatosensory functions were normal. The appreciation of substance qualities (hylognosia) was preserved, but the patient's inability to recognize the size and shape (morphagnosia) was confined to 2- and 3-dimensional shapes (amorphagnosia) in the left hand. However, the patient's ability to recognize real daily objects was well preserved. Brain MRI after admission showed ischemic lesions confined to the right pre- and postcentral gyri and the medial frontal cortex on DWI and FLAIR images. An analysis of SPECT images revealed that the most decreased areas were localized to the pre- and postcentral gyri, superior and inferior parietal lobules, supramarginal gyrus, and angular gyrus. Considering the previous reported cases, the responsible lesion for the impaired perception of hylognosia and morphagnosia may not necessarily be confined to the right hemisphere. To date, 5 reports (6 cases) of tactile agnosia have been published; 4 cases presented with both ahylognosia and amorphagnosia, while 1 presented with only amorphagnosia, and another showed amorphagnosia and mild ahylognosia. Our case is the first to present with only amorphagnosia without tactile agnosia. The mechanism for the well-preserved recognition of real objects may depend on the preserved hylognosia. Of note, there have been no reports showing only ahylognosia without amorphagnosia. Further studies are necessary to clarify whether or not patients with preserved hylognosia or morphagnosia retain the ability to perceive real objects.

[A case of an anti-SRP myopathy with enlargement of the thymus]

A 54-year-old female was admitted to our hospital because of the Raynaud phenomenon and muscle weakness of the upper limbs. The neurological findings showed somatic and proximal limb weakness. Laboratory studies showed a high serum creatine kinase level. Computerized tomography (CT) revealed enlargement of the thymus. A muscle biopsy showed a small number of degenerating and regenerating fibers but no inflammatory infiltrations. At first, she was initially treated with a three-day course of intravenous methylprednisolone (1 g/day). However, the weakness progressed and the serum creatine kinase level remained high. She was subsequently treated with a combination of tacrolimus (3 mg/day) and prednisolone, but showed no any improvement of the muscle weakness. Following additional treatment with intravenous immunoglobulin, she showed improvement in her muscle weakness. Further, anti-signal recognition particle antibodies were identified after treatment. There have been no previous reports of myopathy with antibodies against the signal recognition particle and enlargement of the thymus, so we herein report the details of this unique case.

Bunina bodies in motor and non-motor neurons revisited: a pathological study of an ALS patient after long-term survival on a respirator

Bunina bodies (BBs) are small eosinophilic neuronal cytoplasmic inclusions (NCIs) found in the remaining lower motor neurons (LMNs) of patients with sporadic amyotrophic lateral sclerosis (SALS), being a specific feature of the cellular pathology. We examined a case of SALS, unassociated with TDP-43 or C9ORF72 mutation, of 12 years duration in a 75-year-old man, who had received artificial respiratory support for 9 years, and showed widespread multisystem degeneration with TDP-43 pathology. Interestingly, in this patient, many NCIs reminiscent of BBs were observed in the oculomotor nucleus, medullary reticular formation and cerebellar dentate nucleus. As BBs in the cerebellar dentate nucleus have not been previously described, we performed ultrastructural and immunohistochemical studies of these NCIs to gain further insight into the nature of BBs. In each region, the ultrastructural features of these NCIs were shown to be identical to those of BBs previously described in LMNs. These three regions and the relatively well preserved sacral anterior horns (S1 and S2) and facial motor nucleus were immunostained with antibodies against cystatin C (CC) and TDP-43. Importantly, it was revealed that BBs exhibiting immunoreactivity for CC were a feature of LMNs, but not of non-motor neurons, and that in the cerebellar dentate nucleus, the ratio of neurons with BBs and TDP-43 inclusions/neurons with BBs was significantly lower than in other regions. These findings suggest that the occurrence of BBs with CC immunoreactivity is intrinsically associated with the particular cellular properties of LMNs, and that the mechanism responsible for the formation of BBs is distinct from that for TDP-43 inclusions.

Thymus histology and concomitant autoimmune diseases in Japanese patients with muscle-specific receptor tyrosine kinase-antibody-positive myasthenia gravis

BACKGROUND AND PURPOSE

The differences in the characteristics of thymus histology, coexisting autoimmune diseases and related autoantibodies between anti-muscle-specific receptor tyrosine kinase (MuSK)-antibody (Ab)-positive myasthenia gravis (MG) patients, and anti-acetylcholine receptor (AChR)-Ab-positive MG patients are not clearly defined.

METHODS

The types of thymus histology, coexisting autoimmune diseases and associated Abs in 83 MuSK-Ab-positive patients nationwide were investigated and were compared with those in AChR-Ab-positive patients followed at our institute (n = 83). As for the autoantibodies associated with thymoma, titin Abs were measured.

RESULTS

Thymoma was not present in any of the MuSK-Ab-positive patients but presented in 21 patients (25.3%) amongst the AChR-Ab-positive patients. Titin Abs were absent in MuSK-Ab-positive patients but positive in 25 (30.1%) of the AChR-Ab-positive patients. Concomitant autoimmune diseases were present in eight MuSK-Ab-positive patients (9.6%) amongst whom Hashimoto's thyroiditis and rheumatoid arthritis predominated, whereas 22 AChR-Ab-positive patients (26.5%) had one or more concomitant autoimmune diseases of which Graves' disease predominated.

CONCLUSIONS

Differences in frequency of thymoma and thymic hyperplasia, coexisting autoimmune diseases and autoantibody positivity between MuSK-Ab-positive and AChR-Ab-positive MG were indicated, suggesting that, in contrast with AChR-Ab-positive MG, thymus does not seem to be involved in the pathogenic mechanisms of MuSK-Ab-positive MG.

Antibodies against the main immunogenic region of the acetylcholine receptor correlate with disease severity in myasthenia gravis

OBJECTIVE

We developed an assay that detects autoantibodies against the main immunogenic region (MIR) located at the extracellular end of the nicotinic acetylcholine receptor (AChR) α subunit, and investigated its clinical relevance in myasthenia gravis (MG).

METHODS

In this retrospective cohort study, we measured MIR antibody (Ab) titres in sera obtained before treatment and analysed their associations with clinical parameters in 102 MG patients from two neurological centres. MIR Ab titres were determined using a modified competition immunoprecipitation assay in the presence or absence of monoclonal antibody 35.

RESULTS

11 of 23 (47.8%) ocular type and 66 of 72 (91.7%) generalised type MG patients were positive for the presence of MIR Abs, defined as a titre >16.8% (3 SDs above the mean for 70 healthy controls). A significantly higher MIR Ab titre (p<0.001) was shown in generalised type (47.9±19.2%) rather than in ocular type MG patients (16.4±8.4%). Bivariate regression analysis using both titre levels of MIR Ab and routine AChR binding Ab as variables revealed MIR Abs to be an exclusive indicator positively associated with disease severity (Myasthenia Gravis Foundation of America classification, p<0.0001; Quantitative MG score, p=0.008), the presence of bulbar symptoms (p<0.0001) and thymoma (p=0.016), and negatively associated with ocular MG (p<0.0001).

CONCLUSIONS

MIR Ab titre levels show much better correlations with factors related to disease severity compared with AChR binding Ab titres. The MIR Ab assay may be useful for predicting MG symptom severity, especially for discriminating between ocular and generalised types of MG.

[Histochemical findings of and fine structural changes in motor endplates in diseases with neuromuscular transmission abnormalities]

We herein review the histochemical findings and fine structural changes of motor endplates associated with diseases causing neuromuscular transmission abnormalities. In anti-acetylcholine receptor (AChR) antibody-positive myasthenia gravis (MG), type 2 fiber atrophy is observed, and the motor endplates show a reduction in the nerve terminal area, simplification of the postsynaptic membrane, decreased number of acetylcholine receptors, and deposition of immune complexes. In anti-MuSK antibody-positive MG, the fine structure shows a decrease in the postsynaptic membrane length, but the secondary synaptic cleft is preserved. There is no decrease in the number of AChRs, and there are no deposits of immune complexes at the motor endplates. Patients with Lambert-Eaton myasthenic syndrome show type 2 fiber atrophy, their motor endplates show a decrease in both the mean postsynaptic area and postsynaptic membrane length in the brachial biceps muscle. Congenital myasthenic syndrome with episodic apnea is characterized only by small-sized synaptic vesicles; the postsynaptic area is preserved. In subjects with congenital myasthenic syndrome with acetylcholinesterase deficiency, quantitative electron microscopy reveals a significant decrease in the nerve terminal size and presynaptic membrane length; further, the Schwann cell processes extend into the primary synaptic cleft, and partially or completely occlude the presynaptic membrane. The postsynaptic folds are degenerated, and associated with pinocytotic vesicles and labyrinthine membranous networks. Patients with slow-channel congenital myasthenia syndrome show type 1 fiber predominance, and their junctional folds are typically degenerated with widened synaptic space and loss of AChRs. Patients with AChR deficiency syndrome caused by recessive mutations in AChR subunits also show type 1 fiber predominance, and while most junctional folds are normal, some are simplified and have smaller than normal endplates. Rapsin and MuSK mutations cause type 1 fiber predominance, and the small postsynaptic area is associated with AChR decrease.

[A patient with prosopagnosia which developed after an infarction in the left occipital lobe in addition to an old infarction in the right occipital lobe]

A 66-year-old, right-handed male, was admitted to our hospital with difficulty in recognizing faces and colors. He had suffered a stroke in the right occipital region three years earlier that had induced left homonymous hemianopsia, but not prosopagnosia. A neurological examination revealed prosopagnosia, color agnosia, constructional apraxia, and topographical disorientation, but not either hemineglect or dressing apraxia. The patient was unable to distinguish faces of familiar persons such as his family and friends, as well as those of unfamiliar persons such as doctors and nurses. Brain MRI demonstrated an old infarction in the right medial occipital lobe and a new hemorrhagic infarction in the left medial occipital lobe, including the fusiform and lingual gyrus. It is unclear whether a purely right medial occipital lesion can be responsible for prosopagnosia, or whether bilateral medial occipital lesions are necessary for this occurrence. The current case indicated that bilateral medial occipital lesions play an important role in inducing porsopagnosia.

Sporadic four-repeat tauopathy with frontotemporal lobar degeneration, Parkinsonism, and motor neuron disease: a distinct clinicopathological and biochemical disease entity

Tau is the pathological protein in several neurodegenerative disorders classified as frontotemporal lobar degeneration (FTLD), including corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP). We report an unusual tauopathy in three Japanese patients presenting with Parkinsonism and motor neuron disease (neuroimaging revealed frontotemporal cerebral atrophy in two patients who were examined). At autopsy, all cases showed FTLD with the most severe neuronal loss and gliosis evident in the premotor and precentral gyri. Although less severe, such changes were also observed in other brain regions, including the basal ganglia and substantia nigra. In the spinal cord, loss of anterior horn cells and degeneration of the corticospinal tract were evident. In addition, the affected regions exhibited neuronal cytoplasmic inclusions resembling neurofibrillary tangles. Immunostaining using antibodies against hyperphosphorylated tau and 4-repeat tau revealed widespread occurrence of neuronal and glial cytoplasmic inclusions in the central nervous system; the astrocytic tau lesions were unique, and different in morphology from astrocytic plaques in CBD, or tufted astrocytes in PSP. However, immunoblotting of frozen brain samples available in two cases revealed predominantly 4R tau, with the approximately 37-kDa and 33-kDa low-molecular mass tau fragments characteristic of CBD and PSP, respectively. No mutations were found in the tau gene in either of the two cases. Based on these clinicopathological, biochemical, and genetic findings, we consider that the present three patients form a distinct 4R tauopathy associated with sporadic FTLD.

Anti-cyclic citrullinated peptide antibody (anti-CCP antibody) is present in the sera of patients with dementia of Alzheimer's type in Asian

BACKGROUND

In the hippocampi of Alzheimer's disease (AD) patients, aberrant expression of citrullinated proteins and peptidylarginase 2 (PADI2) has been identified. We explored the functional roles of these proteins by means of detection of serum anti-cyclic citrullinated peptide antibody (anti-CCP antibody) in patients with dementia of Alzheimer's type (DAT).

METHODS

Sera were obtained from 42 patients with DAT, 30 patients with other neurological disorders and 42 healthy controls. Gender ratio and age were comparable among the three groups. The level of anti-CCP antibody in sera was examined by ELISA.

FINDINGS

Anti-CCP antibody was not found in the 30 patients with other neurological disorders, and only one of the 42 healthy controls (2.4%) was positive. However, surprisingly, anti-CCP antibody was clearly detected in eight of the 42 DAT patients.

INTERPRETATION

Anti-CCP antibody appears to be a simple and early serologic biomarker for DAT among dementia patients. Additionally, our data imply that citrullinated proteins accumulated in the astrocytes of AD patients acquire neo-antigenicity, inducing anti-CCP antibody production.

Age-related white matter hyperintensities attenuated by compression from a chronic subdural hematoma: possible contribution of brain interstitial fluid to the formation of leukoaraiosis

The origin of patchy white matter hyperintensities commonly seen in the elderly on magnetic resonance (MR) images with long repetition time (TR) is still controversial. We describe MR findings in older patients in whom white matter hyperintensities were attenuated by compression of the cerebral hemisphere from a chronic subdural hematoma. These sequential MR findings substantiate the hypothesis that leukoaraiosis may arise when drainage of the bulk flow of brain interstitial fluid is disturbed.

Sporadic amyotrophic lateral sclerosis of long duration is associated with relatively mild TDP-43 pathology

Recently, sporadic amyotrophic lateral sclerosis (SALS), a fatal neurological disease, has been shown to be a multisystem proteinopathy of TDP-43 in which both neurons and glial cells in the central nervous system are widely affected. In general, the natural history of SALS is short (<5 years). However, it is also known that a few patients may survive for 10 years or more, even without artificial respiratory support (ARS). In the present study using TDP-43 immunohistochemistry, we examined various regions of the nervous system in six patients with SALS of long duration (10-20 years) without ARS, in whom lower motor-predominant disease with Bunina bodies and ubiquitinated inclusions (UIs) in the affected lower motor neurons was confirmed. One case also showed UIs in the hippocampal dentate granule cells (UDG). In all cases, except one with UDG, the occurrence of TDP-43-immunoreactive (ir) neuronal cytoplasmic inclusions (NCIs) was confined to a few regions in the spinal cord and brainstem, including the anterior horns. In one case with UDG, TDP-43-ir NCIs were also detected in the substantia nigra, and some regions of the cerebrum, including the hippocampal dentate gyrus (granule cells). The number of neurons displaying NCIs in each region was very small (1-3 per region, except the dentate gyrus). On the other hand, the occurrence of TDP-43-ir glial cytoplasmic inclusions (GCIs) was more widespread in the central nervous system, including the cerebral white matter. Again, however, the number of glial cells displaying GCIs in each region was very small (1-3 per region). In conclusion, compared to the usual form of SALS, TDP-43 pathology shown in SALS of long duration was apparently mild in degree and limited in distribution, corresponding to the relatively benign clinical courses observed. It is now apparent that SALS of long duration is actually part of a TDP-43 proteinopathy spectrum.

[Overview: MuSK/Dok-7]

MuSK/Dok-7 mediate the clustering of acetylcholine receptor (AChR) during synapse formation and are expressed at the mature neuromuscular junction. These proteins are deeply associated with myasthenia gravis (MG) and congenital myasthenic syndrome (CMS). Compared with MG patients with AChR antibodies, those with muscle-specific tyrosine kinase (MuSK) antibodies are more likely to present oculobulbar than limb weakness, myasthenic crisis and muscle wasting. None have thymoma, so the indication for thymectomy should be investigated. MuSK antibodies do not appear to cause complement-mediated morphological motor endplate damage, but how they cause myasthenic symptoms is unclear. As the results, the three types of MG presently characterized by known antibody targets are classified into 1) AChR antibody-positive, 2) MuSK antibody -positive, and 3) double seronegative type which the above-mentioned antibodies are negative. In 2006, MuSK-interacting cytoplasmic protein termed Dok-7 has been found. Subsequently, mutations in Dok-7 as a cause of CMS were identified, providing evidence for a crucial role of Dok-7 in maintaining synaptic structure. Their effect on MuSK/Dok -7 function needs to be explored.

Total tau protein in cerebrospinal fluid and diffusion-weighted MRI as an early diagnostic marker for Creutzfeldt-Jakob disease

BACKGROUND

We have recently begun to doubt the effectiveness of periodic sharp wave complexes observed on electroencephalographs and the detection of 14-3-3 protein in cerebrospinal fluid (CSF) as diagnostic criteria for Creutzfeldt-Jakob disease (CJD). Diffusion-weighted magnetic resonance imaging (DWI) and the detection of total tau (t-tau) protein in CSF may be more sensitive diagnostic criteria.

METHODS

Among 44 CJD patients, we selected 21 subjects that suffered from early-stage CJD, which was defined as cases in the 6 weeks following the onset of the disease. The sensitivities of DWI and electroencephalographs, as well as those of t-tau protein, 14-3-3 protein, neuron-specific enolase (NSE), and S-100b protein in CSF were compared as diagnostic markers for early-stage CJD.

RESULTS

NSE, S-100b protein, t-tau protein, and 14-3-3 protein were detected in the samples from 57.1, 4.8, 95.2, and 76.2% of the 21 early-stage CJD patients, respectively. Additionally, DWI was used to positively identify 90.5% of these cases.

CONCLUSION

We concluded that t-tau protein was the most sensitive of the diagnostic markers for CJD. Moreover, the data in this study showed that detection of t-tau protein combined with DWI identified 98% of the early-stage cases, and these tests should be included as diagnostic criteria for CJD.

Chronological changes in MRI and CSF biochemical markers in Creutzfeldt-Jakob disease patients

BACKGROUND

There are currently no markers for evaluating chronological changes in Creutzfeldt-Jakob disease (CJD). We examined if chronological changes in biochemical markers in cerebrospinal fluid (CSF) and diffusion-weighted magnetic resonance imaging (DWI) were utilizable for this purpose.

METHODS

Ten independent patients were divided into two groups of 5 patients each. We analyzed CSF biochemical markers, DWI and the clinical course in one group. In the remaining group, only the CSF biochemical markers were analyzed before and after the onset of akinetic mutism.

RESULTS

The level of total tau (t-tau) protein in CSF in the early phase after disease onset was 2,655 +/- 423.9 pg/ml, reaching a mean peak of 14,675 +/- 1,240 pg/ml in the middle phase and gradually declining after that. Just before patients deteriorated into akinetic mutism, t-tau protein titers reached a maximum (8,786 +/- 2,975 pg/ml). There were dramatic changes in t-tau protein levels throughout the clinical course, unlike the other markers. DWI was not always utilizable, because of discordance with clinical symptoms seen in this study. Four cases exhibited peaks in t-tau protein levels while the patients fell into akinetic mutism except 1 case.

CONCLUSION

Our results suggest that t-tau protein is the most sensitive marker of disease progression in CJD patients.

14-3-3 protein, total tau and phosphorylated tau in cerebrospinal fluid of patients with Creutzfeldt-Jakob disease and neurodegenerative disease in Japan

1. Sporadic Creutzfeldt-Jakob disease (CJD) is a rapidly progressive and fatal disease. Patients with CJD usually become akinetic mutism within approximately 6 months. In addition, clinical signs and symptoms at early stage of sporadic CJD may not be easy to distinguish from other neurodegenerative diseases by neurological findings. However, diagnostic biochemical parameters including 14-3-3 protein, S100, neuron-specific enorase in cerebrospinal fluid (CSF) have been used as diagnostic markers, elevated titers of these markers can also be observed in CSF in other neurodegenerative diseases. Therefore, we examined other biochemical markers to discriminate CJD from other neurodegenerative diseases in CSF. 2. We analyzed CSF samples derived from 100 patients with various neurodegenerative disorders by Western blot of 14-3-3 protein, quantification of total tau (t-tau) protein, and phosphorylated tau (p-tau) protein. All patients with CJD in this study showed positive 14-3-3 protein and elevated t-tau protein (>1000 pg/mL) in CSF. We also detected positive 14-3-3 protein bands in two patients in non-CJD group (patients with dementia of Alzheimer's type; DAT) and also detected elevated t-tau protein in three patients in non-CJD group. Elevated t-tau protein levels were observed in two patients with DAT and in one patient with cerevrovascular disease in acute phase. 3. To distinguish patients with CJD from non-CJD patients with elevated t-tau protein in CSF, we compared the ratio of p-tau and t-tau proteins. The p-/t-tau ratio was dramatically and significantly higher in DAT patients rather than in CJD patients. 4.Therefore, we concluded that the assay of t-tau protein may be useful as 1st screening and the ratio of p-tau protein/t-tau protein would be useful as 2nd screening to discriminate CJD from other neurodegenerative diseases.

[Hyperintense optic nerve lesion on T2-weighted MRI imaging in the acute stage of Leber's hereditary optic neuropathy: a case report]

A 46-year-old man was admitted to our hospital for acute onset, bilateral visual disturbance. Neither papilledema nor optic atrophy was found. Brain MRI revealed a hyperintense lesion in the optic chiasm on T2-weighted imaging. No enhancement was detected in gadolinium-enhanced MRIs. Based on these results, a diagnosis of retrobulbar neuritis was made, and steroid pulse therapy was performed. However, the visual acuity did not improve at all. We therefore suspected Leber's hereditary optic neuropathy (LHON) and thus performed a PCR analysis of the mitochondrial DNA. It revealed a G to A transition at nucleotide position 11778 of the mitochondrial DNA, which has been frequently observed in LHON patients in Japan. Based on the above findings, when middle-aged patients present an acute onset of visual loss, LHON should be included in the differential diagnosis.

Sporadic four-repeat tauopathy with frontotemporal degeneration, parkinsonism and motor neuron disease

We report a sporadic tauopathy of 6-year duration in a 76-year-old woman. Her initial symptoms were asymmetrical parkinsonism and muscle weakness, with apraxia appearing 2 years later. The brain showed frontal and temporal cerebral atrophy; severe neuronal loss and gliosis were observed in the precentral cortex (loss of Betz cells was also evident) and premotor area, and in the medial temporal lobe, including the temporal tip, amygdala, and hippocampal CA1-subiculum border zone. The substantia nigra showed moderate neuronal loss and gliosis. In the spinal cord, loss of the anterior horn cells and degeneration of the corticospinal tracts were a characteristic feature. In addition, in the affected regions, the remaining neurons were often found to contain intracytoplasmic inclusions resembling neurofibrillary tangles. Tau immunostaining revealed widespread glial-predominant lesions in the cerebral gray and white matter. In contrast, predominance of neuronal lesions (pretangles/tangles) was a feature in the subcortical gray matter, including the spinal cord. The remaining upper and lower motor neurons were also affected by tau pathology. Accumulated tau in these glial cells and neurons was clearly recognized by a specific antibody against four-repeat (4R) tau. The ultrastructural presence of tau-positive tubular structures was confirmed in the glial cells and neurons (tangles). Immunoblotting of a frozen frontal lobe sample revealed accumulation of 4R-predominant tau isoforms. No mutations were found in the tau gene. These findings indicate that a sporadic 4R tauopathy can cause frontotemporal degeneration, parkinsonism, and motor neuron disease. The present case could represent a new clinicopathological phenotype of non-familial tauopathy.

Acetylcholine receptors loss and postsynaptic damage in MuSK antibody-positive myasthenia gravis

Muscle-specific tyrosine kinase (MuSK) antibodies are found in some patients with "seronegative" myasthenia gravis (MG), but how they cause myasthenic symptoms is not clear. We visualized acetylcholine receptors (AChRs) and complement component 3 (C3) in muscle biopsies from 10 Japanese MG patients with MuSK antibodies, compared with 42 with AChR antibodies. The AChR density was not significantly decreased in MuSK antibody (Ab)-positive end-plates compared with AChR antibody-positive end-plates, and C3 was detected in only two of eight MuSK Ab-positive patients. MuSK antibodies do not appear to cause substantial AChR loss, complement deposition, or morphological damage. Effects on MuSK function need to be explored.

[Serial diffusion-weighted MRI (DWI) in a patient with sporadic Creuztfeldt-Jakob disease]

Serial DWIs were performed in a patient with CJD who developed symptoms acutely and progressed rapidly. DWI discloed an increased signal in the frontal and parietal inner cortical areas, and in the caudate nuclei and putamina 20 days after the onset of symptoms. T2-weighted images showed only signal abnormality in the caudate nuclei and putamina, but not in the cerebral cortex. In the CSF obtained 15 days after the onset of symptoms, total tau protein was markedly elevated and 14-3-3 protein was positive. Measurement of these proteins are highly specific and sensitive for the diagnosis of CJD, but not available as a rapid routine examination at present. DWI is not specific, but useful for making the diagnosis of CJD in the early stage of the disease.

LRP5, low-density-lipoprotein-receptor-related protein 5, is a determinant for bone mineral density

Osteoporosis is a multifactorial trait with low bone mineral density (BMD). We report results of an association study between BMD and nine candidate genes ( TGFB1, TGFBR2, SMAD2, SMAD3, SMAD4, IFNB1, IFNAR1, FOS and LRP5), as well as of a case-control study of osteoporosis. Samples for the former association study included 481 general Japanese women. Among the nine candidate genes examined, only LRP5 showed a significant association with BMD. We identified a strong linkage disequilibrium (LD) block within LRP5. Of five LPR5 single nucleotide polymorphisms (SNPs) that are located in the LD block, three gave relatively significant results: Women with the C/C genotype at the c.2220C>T SNP site had higher adjusted BMD (AdjBMD) value compared to those with C/T and T/T (p=0.022); and likewise, G/G at IVS17-30G>A and C/C women at c.3989C>T showed higher AdjBMD than those with G/A or A/A (p=0.039) and with C/T or T/T ( p=0.053), respectively. The case-control study in another series of samples consisting of 126 osteoporotic patients and 131 normal controls also gave a significant difference in allele frequency at c.2220C>T (kappa2=6.737, p=0.009). These results suggest that LRP5 is a BMD determinant and also contributes to a risk of osteoporosis.

Characterization of anticytoplasmic antibodies in patients with systemic autoimmune diseases

Abstract We characterized the cytoplasmic staining patterns identified by indirect immunofluorescence (IF) using human epithelial (HEp-2) cells as substrates, and identified autoantigens using enzyme-linked immunosorbent assay (ELISA) and cognate RNA immunoprecipitation techniques in cytoplasmic antibody-positive sera (CA(+)) in patients with systemic autoimmune diseases. Twenty-three sera (3.7%) of 630 patients were found to have a cytoplasmic staining pattern by IF on HEp-2 cells. The fine-pattern IF specificities were as follows: 12 diffuse fine speckled; 7 coarse granular filamentous speckled; 2 diffuse coarse speckled; 1 condensed large speckled; 1 cytoskeletal. No relationship was found between the staining patterns and the diseases. Anti-SS-A antibodies and antimitochondrial (M2) antibodies were detected by ELISA in 6 and 4 sera, respectively, and antismooth muscle antibody was detected by IF in 1 serum. In RNA immunoprecipitation assays, 6, 11, 3, and 1 patients had antibodies that recognized aminoacyltransfer RNA (tRNA) synthetases (including 2 EJ, 2 PL-7, 1 PL-12, and 1 unidentified tRNA-related), SS-A, ribosomes, and SRP, respectively. Moreover, several other autoantigens were detected by Western blotting using human epithelial (HEp-2) cell lysates. This study suggests that autoantibodies against tRNA synthetases, SS-A, ribosomes, mitochondria, and other autoantigens are present in CA(+) sera from patients with a variety of systemic autoimmune diseases.

[A case of extramedullary multiple myeloma manifested as an epidural mass in the cervical spinal cord]

A 76-year-old man who rapidly developed quadriparesis was admitted to our hospital. MRI showed an epidural mass extending from C4 to C6, displacing the spinal cord anteriorly. It showed isointensity on the T1-weighted imagines, hyperintensity on the T2-weighted images, and diffuse hyperintensity with gadolinium enhancement. Plain radiographs, CT and MRI showed no evidence of bone involvement. Serum immunoelectrophoresis disclosed M-components of IgA and lambda light chains. This is the first report that an epidural myeloma in the cervical spinal cord caused compression of the cord without evidence of bone involvement.

Reduction of P/Q-type calcium channels in the postmortem cerebellum of paraneoplastic cerebellar degeneration with Lambert-Eaton myasthenic syndrome

The aim of this study was to clarify whether autoimmunity against P/Q-type voltage-gated calcium channels (VGCCs) in the cerebellum was associated with the pathogenesis of paraneoplastic cerebellar degeneration (PCD) with Lambert-Eaton myasthenic syndrome (LEMS). We used human autopsy cerebellar tissues from three PCD-LEMS patients and six other disease patients including one with LEMS as the controls. We compared cerebellar P/Q-type VGCC in these patients and controls for the amount and ratio of autoantibody-channel complex using an 125I-omega-conotoxin MVIIC-binding assay with Scatchard analysis, and their distribution using autoradiography. The quantity of cerebellar P/Q-type VGCC measured by Scatchard analysis were reduced in PCD-LEMS patients (63.0 +/- 7.0 fmol/mg, n = 3), compared with the controls (297.8 +/- 38.9 fmol/mg, n = 6). The ratio of autoantibody-VGCC complexes to total P/Q-type VGCCs measured by immunoprecipitation assay were increased in PCD-LEMS patients. We analysed cerebellar specimens by autoradiography using (125)I-omega-conotoxin MVIIC, which specifically binds to P/Q-type VGCCs. In PCD-LEMS cerebellum, the toxin binding sites of P/Q-type VGCCs were markedly reduced compared with controls, especially in the molecular layer, which is the richest area of P/Q-type VGCCs in the normal cerebellum. This suggests that P/Q-type VGCCs of the cerebellar molecular layer is the immunological target in developing PCD-LEMS.

Effect of myasthenic immunoglobulin G on motor end-plate morphology

This study was undertaken to clarify the role of complement in acetylcholine receptor loss and degeneration of the postsynaptic membrane in myasthenia gravis (MG). We examined the end-plate morphology in rats with passively transferred immunoglobulin G (IgG) from myasthenic patients and the effect of complement by treatment of the rats with cobra venom factor. We injected peroxidase-labeled alpha-BuTx (P-BuTx) into the extensor digitorum longus (EDL) muscle to label the motor end-plates. Three hours later, 100 mg of IgG from MG patients or healthy controls was injected into the tail vein. The EDL was removed 48 hours after the injection of IgG. The presence of macrophages and degeneration of the postsynaptic membrane were seen in 4 of 6 IgG samples from MG patients and a decrease in AChRs in the other 2 samples. These changes were reversed completely by treatment with cobra venom factor in all but one case in which the end-plates were severely degenerated. Injection of MG IgG only never induced end-plate morphology changes. The results suggest that complement has a critical role in degeneration of the postsynaptic membrane and AChR loss at the motor end-plates in the passively transferred model and probably in human MG.

Seronegative Lambert-Eaton myasthenic syndrome: study of 110 Japanese patients

The authors characterized the clinical and immunologic features of 110 patients with Lambert-Eaton myasthenic syndrome (LEMS). Anti-P/Q-type voltage-gated calcium channels (VGCC) antibodies were detected in 85% of the patients (seropositive) but not in the rest (seronegative). Except for the indication that small cell lung carcinoma is less common in seronegative patients, no significant differences were found in the clinical characteristics of patients who had or did not have anti-P/Q-type VGCC antibodies. The results of passive transfer experiments suggest that seronegative LEMS is also an autoantibody-mediated disorder.

Laparoscopic diagnosis and treatment of nonpalpable testis

OBJECTIVE

Laparoscopy has become one of the important diagnostic modalities of nonpalpable testis and has been developed and applied in the treatment of this disease. In the present study, we investigated the usefulness of laparoscopy in the diagnosis and treatment of nonpalpable testis.

METHODS

Laparoscopy was carried out under general anesthesia on 21 patients (23 testes) from October 1991 to October 1999. If the internal spermatic vessels and vas deferens made their way into the internal inguinal ring, the inguinal canal was dissected with an incision in the inguinal region to look for the testis. Patients with intra-abdominal testis underwent laparoscopic orchiopexy or orchiectomy. If the internal spermatic vessels terminated with a blind end intraperitoneally, making it impossible to identify the testis, the case was judged to be vanishing testis and the operation was finalized without any further examination.

RESULTS

In eight of 23 testes (35%), the internal spermatic vessels and vas deferens made their way into the internal inguinal ring. The inguinal region was examined in all the eight testes. Orchiopexy was carried out on two testes and orchiectomy was carried out on six testes. An intra-abdominal testis was detected in eight of 23 testes (35%). Laparoscopic orchiopexy was carried out on seven testes. One-stage orchiopexy was carried out on two of the seven testes and two-stage Fowler-Stephens orchiopexy was carried out on five of the seven testes. Orchiectomy was carried out on the remaining testis. Blocking or lack of the internal spermatic vessels and vas deferens was seen in seven of the 23 testes (30%) and this condition was diagnosed as vanishing testis.

CONCLUSION

Laparoscopy for nonpalpable testis is considered to be the most effective technique for diagnosing the presence or absence of the testis and the location of the testis.

Comparison of fibronectin content in urinary macromolecules between normal subjects and recurrent stone formers

OBJECTIVES

Fibronectin (FN: 230 kD) is a multifunctional alpha(2)-glycoprotein distributed throughout the extracellular matrix and body fluids. Recent studies have shown that a variety of molecules, including FN, inhibit the endocytosis of calcium oxalate (CaOx) crystals in vitro. We recently reported that FN was oversecreted from the renal tubular cells as a result of the stimulation of CaOx crystals, and inhibited the aggregation of CaOx crystals and the adhesion of CaOx crystals to the renal tubular cells. In the present study, we investigated the difference of FN content in urinary macromolecules (UMMs) between normal subjects and recurrent stone formers.

MATERIALS AND METHODS

Urinary parameters in relation to urolithiasis of normal subjects and recurrent stone formers were measured. Proteins in extracted UMMs from urine of normal subjects and recurrent stone formers were measured with a BioRad protein assay, GAGs in each UMMs with a modified DMB assay and the FN content with the ELISA method.

RESULTS

In urinary parameters, citrate was significantly higher in urine from normal subjects (female) than normal subjects (male) or recurrent stone formers, and the other parameters showed no differences between each group. The protein concentrations in UMMs showed no differences between each group. Normal subjects (male and female) showed a significantly higher concentration of GAGs than recurrent stone formers (with and without silent stone). Compared with normal subjects and recurrent stone formers without silent stones, higher FN levels were found in recurrent stone formers with silent stones. Normal subjects showed a significantly higher concentration of FN than recurrent stone formers without silent stones. No difference in FN level was shown between normal subjects (male) and normal subjects (female).

CONCLUSION

Recurrent stone formers with silent stones showed a significantly higher concentration of FN in UMMs than normal subjects. This finding suggests that FN might be oversecreted from the renal tubular cells as a result of the stimulation of CaOx stones in vivo. Recurrent stone formers without silent stones showed a significantly lower concentration of FN in UMMs than normal subjects. From this finding it is suggested that FN might play a role as a potent inhibitor of CaOx urolithiasis in a clinical setting.

Strong inhibition of crystal-cell attachment by pediatric urinary macromolecules: a close relationship with high urinary citrate secretion

OBJECTIVES

To investigate other reasons for the low incidence of pediatric urolithiasis, we evaluated the difference in the crystal-cell adhesion inhibitory activity of urinary macromolecules (UMMs) between children and adults. We also evaluated whether citrates influence the above inhibitory activity, because citrates are important in pediatric urine.

METHODS

Urine samples were collected from children and healthy male adults during a 24-hour period, and urinary components with a molecular weight of 3 kDa or greater were extracted as UMMs to compare their inhibitory activity during the adhesion of calcium oxalate monohydrate crystals to cultured Madin-Darby canine kidney cells between children and adults. Subsequently, various concentrations of citrates were added to adult UMMs to evaluate the changes in the crystal-cell adhesion inhibitory activity of UMMs.

RESULTS

Pediatric UMMs more strongly inhibited the adhesion of calcium oxalate monohydrate crystals to cultured Madin-Darby canine kidney cells at a concentration of 0.1 mg/mL compared with adult UMMs. In addition, pediatric UMMs contained higher proportions of fibronectin and glycosaminoglycans, both of which exhibit crystal-cell adhesion inhibitory activity. When citrates were added to adult UMMs, the crystal-cell adhesion inhibitory activity of UMMs was increased in a dose-dependent manner. However, citrates alone did not result in any differences in the inhibitory activity at any of the three different concentrations.

CONCLUSIONS

We speculate that the incidence of pediatric urolithiasis is low because pediatric UMMs more potently inhibit the adhesion of calcium oxalate crystals to renal tubular cells or because the higher proportion of citrates in pediatric urine enhances the crystal-cell adhesion inhibitory activity of UMMs in a dose-dependent manner.

[Undescended testicular tumor found by torsion of the testis: a case report]

A 37-year-old man was admitted with a painful mass in his left inguinal region. He had an undescended testis on the left side. Six months earlier, he had noted that his left inguinal testis was larger, and he had suddenly developed pain in the left inguinal region. The levels of AFP, hCG beta and LDH were normal. We diagnosed a left undescended testicular tumor and torsion of the left testis. Left inguinal high orchiectomy showed a torsion of the left testis and histopathological examination of the specimen revealed seminoma.

Semiquantitative measurement of acetylcholine receptor at the motor end-plate in myasthenia gravis

OBJECTIVE

The purpose of this study was to investigate whether this semiquantitative measurement of the motor end-plate acetylcholine receptors (AChRs) can be used to confirm the diagnosis of myasthenia gravis (MG), and in particular ocular MG.

METHODS

Motor point biopsies were performed from the biceps brachii muscles. Measurement of AChRs was made in peroxidase-labeled alpha-bungarotoxin stained muscle specimens.

PATIENTS

Twenty patients with ocular MG, 37 with generalized MG, 5 with Lambert-Eaton myasthenic syndrome, 3 with botulism, 8 with amyotrophic lateral sclerosis, and 8 controls were included in this study.

RESULTS

AChRs were decreased in all patients with generalized MG and in 80% of ocular MG including patients without detectable circulating anti-AChR antibodies, as compared with the control subjects.

CONCLUSION

This method is useful to confirm the diagnosis of MG, in particular ocular MG without detectable anti-AChR antibodies.

A novel role for interleukin-18 in human natural killer cell death: high serum levels and low natural killer cell numbers in patients with systemic autoimmune diseases

OBJECTIVE

Patients with systemic autoimmune diseases have been reported to have reduced numbers of peripheral blood natural killer (NK) cells compared with healthy subjects. The ability of selected cytokines to trigger NK cell death prompted us to compare the levels of peripheral blood cytokines with the numbers of NK cells in patients with various systemic autoimmune diseases.

METHODS

We used enzyme-linked immunosorbent assays to measure the concentration of selected cytokines (interleukin-18 [IL-18], IL-15, IL-12, IL-2, interferon-gamma [IFNgamma], and tumor necrosis factor alpha [TNFalpha]) in sera from 58 patients with systemic autoimmune diseases and 33 healthy controls. The absolute number of T cells and NK cells in the peripheral blood was measured in parallel using flow cytometry. The ability of selected cytokines to induce NK cell death was then measured using 3,3'-dihexyloxacarbocyanine iodide dye, propidium iodide staining, and caspase 3 activity.

RESULTS

Levels of IL-18, IL-15, IFNgamma, and TNFalpha were elevated in sera from patients with systemic autoimmune diseases compared with normal controls. The percentage of NK cells and natural killer T cells were significantly decreased in the peripheral blood of patients with systemic autoimmune diseases compared with normal controls. Serum concentrations of IL-18, IL-15, and TNFalpha were inversely related to the number of NK cells in both patients and healthy controls. The combination of IL-18 and IL-15 or IL-18 and IL-12 induced NK cell death in vitro. The combination of IL-18 and IL-15 or IL-18 and IL-12 enhanced IFNgamma and TNFalpha production by NK cells in vitro. Cytokine-induced NK cell death is caspase-dependent and is partially blocked by neutralizing antibodies against TNFalpha.

CONCLUSION

High levels of IL-18 and IL-15 are associated with the decreased number of NK cells that is observed in patients with systemic autoimmune diseases.

Fibronectin as a potent inhibitor of calcium oxalate urolithiasis

PURPOSE

Fibronectin (230 kD.) is a multifunctional alpha2-glycoprotein distributed throughout the extracellular matrix and body fluids. Many investigators have demonstrated that fibronectin, because of its cell adhesive action, is related to biological processes such as morphogenesis, wound healing and metastasis. Recent studies have shown that a variety of molecules, including fibronectin, inhibit endocytosis of calcium oxalate crystals in vitro. We investigated other roles of fibronectin in calcium oxalate stone formation.

MATERIALS AND METHODS

Immunoblotting of the crystal surface binding substance obtained from pooled healthy male urine samples was used to analyze whether fibronectin was adsorbed onto the surface of calcium oxalate crystals. To clarify the relationship between fibronectin and calcium oxalate crystals, we performed 6 experiments. Experiment 1 was immunohistochemical examination of fibronectin expression in stone forming rat model kidneys, and experiment 2 examined the fibronectin content of stone forming rat kidney models with the enzyme-linked immunosorbent assay. Experiment 3 was designed to determine fibronectin content of Madin-Darby canine kidney (MDCK) cells stimulated by addition of calcium oxalate crystals and experiment 4 identified the inhibitory effect of fibronectin on calcium oxalate crystal growth by the seed crystal method. For experiment 5 we used an aggregometer system to clarify the inhibitory effect of fibronectin on calcium oxalate crystal aggregation and experiment 6 examined the inhibitory effect of fibronectin on the adhesion of calcium oxalate crystals to MDCK cells.

RESULTS

In the crystal surface binding substance immunoreactive bands at 230 kD., which correspond to the molecular weight of fibronectin, were detected by Western blot analysis. In stone forming rat kidneys strong expression of fibronectin was found on the renal tubules to which the crystals were attached. The fibronectin content of these kidneys was significantly greater than that of kidneys without calcium oxalate crystals. The fibronectin content of MDCK cells tended to increase in proportion to the concentration of calcium oxalate crystals added to the culture medium. The growth inhibition assay showed that the inhibitory effect of fibronectin on calcium oxalate crystal growth was small in relation to the quantity of fibronectin excreted. However, fibronectin had inhibitory effects on calcium oxalate crystal aggregation and adhesion of the crystals to MDCK cells.

CONCLUSIONS

Fibronectin secretion can be stimulated by calcium oxalate crystals, and this protein, which is excreted from the tubular cells, may inhibit calcium oxalate crystal aggregation and attachment to cells.

Proteoglycan core protein in human urine and its possible role on calcium oxalate urolithiasis

BACKGROUND

There are only a few papers reporting on the role of proteoglycan core protein in calcium oxalate stone formation. The present study was carried out to investigate the role of core protein of proteoglycan in human urine on calcium oxalate (CaOx) crystallization.

METHODS

Proteoglycans were collected from whole human urine. The covalently bound glycosaminoglycans (GAG) of proteoglycans were then digested by GAG lyase. The inhibitory activity on CaOx crystal growth in vitro was measured before and after enzyme digestion of proteoglycans. Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the core protein of proteoglycans and the analysis of amino acid sequence were performed.

RESULTS

The core protein showed significant inhibitory activity on CaOx crystal growth, which scarcely changed when compared with that of proteoglycans before enzyme digestion. The SDS-PAGE revealed that the core protein was a single unit with a molecular weight of 26 kDa and amino acid sequencing demonstrated high homology to interalpha-trypsin inhibitor (ITI) light chain (bikunin) with Kunitz inhibitor domain as a core protein.

CONCLUSIONS

The results suggested that human urine contains proteoglycans and a major part of them is ITI light chain (bikunin). The Kunitz inhibitor domain, a core protein of bikunin, has significant inhibitory activity on CaOx crystallization without GAG bound covalently to the core protein.

Bromocriptine protects dopaminergic neurons from levodopa-induced toxicity by stimulating D(2)receptors

Neuroprotective properties of bromocriptine, a D(2) receptor agonist, were investigated using the in vitro neurotoxicity of levodopa for dopaminergic neurons from rat embryonic ventral mesencephalon. Levodopa, when added to the culture medium, showed toxicity which was specific for dopaminergic neurons. Bromocriptine was found to protect dopaminergic neurons from levodopa toxicity. Another D(2) agonist, 2-(N-phenethyl-N-propyl-amino-5-hydroxytetralin, showed similar protective effects. The neuroprotective effect of bromocriptine was inhibited by supplementation of the culture medium with sulpiride, a D(2) antagonist, or by D(2) receptor knockdown with an antisense oligonucleotide. Dopaminergic neurons treated with levodopa showed an increase in free radicals. These data suggest that neuroprotective properties of bromocriptine seen in this cellular model of neurotoxicity are dependent on dopamine D(2) autoreceptor binding and that levodopa toxicity may be related to increased free radical generation in dopaminergic neurons.

Possible causes for the low prevalence of pediatric urolithiasis

OBJECTIVES

To determine why the incidence of pediatric urolithiasis is less than that of adult urolithiasis, we investigated the difference in inhibition of calcium oxalate (CaOX) crystallization between pediatric and adult urinary macromolecules (UMMs).

METHODS

Urinary parameters in relation to urolithiasis, the inhibition of CaOX crystallization of original urine and urine from which UMMs (greater than 3 kDa) had been removed, and the inhibition of CaOX crystal growth and aggregation of UMMs alone were measured. These inhibitory activities were compared between children and adults.

RESULTS

In the original urine, the inhibition of CaOX crystallization was significantly stronger for children than for adults, but was the same in urine from which the UMMs had been removed. The inhibition of CaOX crystal growth by UMMs alone showed no significant differences between children and adults; their inhibition of CaOX crystal aggregation was significantly stronger for children than for adults. Much more glycosaminoglycan (GAG) was included in pediatric UMMs than in adult UMMs, although there was no difference in UMM concentration between urine from children and urine from adults.

CONCLUSIONS

The lower incidence of CaOX lithiasis in children may be attributed, among other factors, to the stronger inhibition of CaOX crystal aggregation by pediatric UMMs, which in turn might be affected by the higher concentration of GAGs in children's urine.

Lewy body-type degeneration in cardiac plexus in Parkinson's and incidental Lewy body diseases

Heart tissues of patients with PD or incidental Lewy body (LB) disease (ILBD) were examined by light and electron microscopy. LBs and alpha-synuclein-positive neurites were identified in the hearts from 9 of 11 patients with PD and from 7 of 7 patients with ILBD. LBs were present in both tyrosine hydroxylase-positive and -negative nerve processes, which are nerves of extrinsic sympathetic and intrinsic origin, respectively. These findings provide histologic evidence that the postganglionic sympathetic and intrinsic neurons in the heart are involved in the PD disease process.