Elemental diet modulates the growth of Clostridium difficile in the gut flora

BACKGROUND AND AIMS

Tube feeding is regarded as a risk factor for Clostridium difficile-associated diarrhoea. Recently, we reported that C. difficile toxin was frequently found in patients receiving an elemental diet. The present study was conducted to clarify whether elemental diets are associated with the growth of C. difficile in the gut flora.

METHODS

C. difficile was cultured for 72 h in various concentrations of elemental diet containing 3% thioglycollate, and the growth rate or activity of C. difficile was evaluated by Gram stain or by measuring optical density at 560 nm. Faecal samples from 10 healthy adults were cultured in elemental diet + 3% thioglycollate. RNA was extracted from faeces with glass powder, which can eliminate PCR inhibitors, and mRNA of C. difficile toxin B was measured by reverse transcription PCR.

RESULTS

Maximum OD560 value during culture in thioglycollate-containing elemental diet was 2.4 times higher than that in thioglycollate alone (P = 0.0163). Viability of C. difficile was decreased in thioglycollate but not in thioglycollate-containing elemental diet. Toxin B mRNA was detected in five faecal samples (50%) before culture and in all samples after culture.

CONCLUSIONS

Our results suggest that an elemental diet can modulate the growth of C. difficile in the gut flora.

CSF hypocretin levels in Guillain-Barre syndrome and other inflammatory neuropathies

CSF hypocretin-1 was measured in 28 Guillain-Barré syndrome (GBS), 12 Miller-Fisher syndrome, 12 chronic inflammatory demyelinating polyneuropathy (CIDP), and 48 control subjects. Seven GBS subjects had undetectably low hypocretin-1 levels (<100 pg/mL). Hypocretin-1 levels were moderately reduced in an additional 11 GBS, 5 Miller-Fisher syndrome, and 1 CIDP subject. Low levels in GBS occurred early in the disease and were associated with upper CNS level abnormalities.

Time course of polyglutamine aggregate body formation and cell death: enhanced growth in nucleus and an interval for cell death

Polyglutamine (polyQ) aggregate bodies are a hallmark of dentatorubral-pallidoluysian atrophy and related neurodegenerative disorders, although the relationship between aggregate body formation and cell death is not clear. We analyzed the kinetics of polyQ aggregate formation and the time intervals for cell death, tracking individual cells using fluorescence video microscopy, for the first time. Expanded polyQ tracts of atrophin-1 with or without nuclear localization signal (NLS) labeled with green fluorescent protein (GFP) were constructed, Q57NLS/GFP and Q56/GFP, respectively. All of the Q57NLS/GFP aggregate bodies were in nuclei, and all of the Q56/GFP aggregate bodies were in cytoplasm. Aggregates of Q56/GFP were larger than those of Q57NLS/GFP. Surprisingly, a kinetic analysis showed that the latter grew 5.37 times faster than the former. The time interval between transfection and cell death was shorter in Q57NLS/GFP, but the time between the end of the rapid growing phase of aggregation and the start of the cell death process did not show a significant difference. Aggregate growth was confirmed to correspond to the accumulated free polyQ by the time of starting aggregation. These findings suggest that aggregate body formation induced by expanded polyQ stretches is a self-limiting process and is enhanced by factor(s) in nuclei, whereas it is not tightly bound to the cell death process.

Human muscle protein degradation in vitro by eosinophil cationic protein (ECP)

To clarify the role of tissue eosinophils in and around inflammatory foci, we purified eosinophil cationic protein (ECP) and examined its effect on muscle protein degradation in vitro. Eosinophil cationic protein was purified from the buffy coat of blood from healthy volunteers. Myofibrillar, soluble sarcoplasmic, and membrane-associated cytoskeletal proteins were fractionated from latissimus dorsi muscle obtained by orthopedic procedures done on a patient with no neurologic abnormalities. After incubation of these fractions with purified ECP, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting were performed. Eosinophil cationic protein degraded the myofibrillar proteins, especially the myosin heavy chain (MHC) and alpha-actinin. It also degraded membrane-associated cytoskeletal proteins dystrophin and spectrin, whereas soluble sarcoplasmic proteins did not undergo proteolysis. Quantitative analysis of the MHC degradation showed that the ECP reaction was dose-dependent and that the optimal pH was 7.0. Protein degradation was not inhibited by heparin or the protease inhibitors leupeptin, E-64, and pepstatin A. Our results suggest that ECP functions in the degradation of myofibrillar and membrane-associated cytoskeletal proteins, indicating that tissue eosinophils have a specific role in muscle fiber degradation in some myopathies associated with numerous tissue eosinophils, such as eosinophilic myositis, eosinophilic myalgia syndrome, and eosinophilic endocardial disease.

Dynamic locomotor function in normals and patients with vertigo

Gait analysis was performed in patients with various vestibular systems using a tactile sensor. There were 4 patients with vestibular neuronitis, 6 patients with large acoustic neuroma and 6 patients with spino-cerebellar degeneration (SCD). Gait phase related parameters such as stance, swing and double support were studied to assess gait stability. Also the area ratio of trajectories of center of force during stance and progression of foot pressure were checked. The calculated value of each variable became high in pathological cases compared with normal controls, and the highest value was obtained in the SCD group. As regards the effect of visual deprivation on stability of gait, the most striking change was found in the large acoustic neuroma group. In a case with a unilateral lesion such as vestibular neuronitis and large acoustic neuroma, foot pressure was greater on the lesion side, especially during gait with eyes closed. As for the foot pressure progression curve, the SCD group showed the most irregular pattern in general, although there were some individual variations. Those results could reflect a functional disorder of the gait control system caused by each disease. Significance of gait analysis is also discussed.

Increased lysosome-related proteins in the skeletal muscles of distal myopathy with rimmed vacuoles

Investigators have speculated that the degenerative process in distal myopathy with rimmed vacuoles (DMRV) mainly involves the lysosomal system. To investigate possible protein abnormalities related to intracellular lysosomal proteolytic pathways in DMRV-affected muscles, we performed immunohistochemical analyses of certain proteins in muscle biopsy specimens obtained from patients with various neuromuscular diseases, including DMRV, muscular dystrophy, polymyositis, and amyotrophic lateral sclerosis, and in normal human muscles specimens. Immunohistochemically, most muscle fibers in normal control specimens showed little or no reaction for clathrin and alpha- and gamma-subunits of adaptin-constituted adaptin proteins (AP)-1 and AP-2, respectively. Abnormal increases in these proteins were demonstrated mainly in the cytoplasm of atrophic fibers or in necrotic fibers in all diseased specimens. Particularly in DMRV-affected muscles, alpha- and gamma-adaptins were often observed inside or on the rims of vacuoles and in the cytoplasm of vacuolated fibers. Abnormal increases in Golgi-zone protein were also demonstrated in DMRV muscles. The rims of rimmed vacuoles were negative for kinectin, an endoplasmic reticulum-binding protein. Positive staining for both proteins, however, was sometimes seen inside the vacuoles in DMRV-affected fibers. These results suggest increased endocytosis at the plasma membrane as well as secretion involving transport from the trans-Golgi network of the Golgi apparatus in DMRV. Accumulation of various lysosome-related proteins within the rimmed vacuoles indicates at least some of these vacuoles may be autolysosomes.

A novel de novo mutation in the desmin gene causes desmin myopathy with toxic aggregates

OBJECTIVE

To determine the cause and pathogenic mechanisms of a 21-year-old patient's cardioskeletal myopathy. The patient's muscle atrophy and weakness began in distal parts of limbs; cardiac and facial muscles were later involved.

BACKGROUND

Desmin myopathy is a skeletal myopathy often associated with cardiomyopathy, caused by mutations in the desmin gene and characterized by desmin accumulation in affected muscle fibers, a leading marker of myofibrillar myopathies. Two kinds of deletions and seven missense mutations in the desmin gene have been identified.

METHODS

Clinical examination, electron microscopy of muscle tissue, two-dimensional gel electrophoresis, DNA sequencing, restriction enzyme analysis, and gene transfection were performed.

RESULTS

Electron microscopy showed disruption of sarcomeres at Z discs and electron-dense aggregates in biopsied skeletal and heart muscle. Two-dimensional gel electrophoresis of the patient's skeletal muscle proteins showed massive accumulation of desmin. The authors identified a novel desmin mutation, L385P in one allele in the carboxyl end of the rod domain 2B in the patient's leukocytes and skeletal muscle; neither parent had the mutation. Serologic study and DNA markers confirmed the de novo mutation. A peptide harboring desmin rod domains 2A and 2B with L385P tagged with green fluorescent protein induced cytoplasmic aggregates, nuclear DNA condensation, and cell death.

CONCLUSIONS

A novel de novo mutation, L385P, causes desmin myopathy. An expression study indicated the toxic effect of the L385P mutation.

Massive accumulation of M and H subunits of neurofilament proteins in spinal motor neurons of neurofilament deficient Japanese quail, Quv

Quiver (Quv) is a non-sense mutation of neurofilament protein L subunit (NF-L) that causes neurofilament deficiency with preserved microtubules in Japanese quail. Anti-NF-M and anti-NF-H mAbs stained cell bodies of motor neurons in Quv embryo spinal cords much more intense than those in control spinal cords. Volume of motor neurons in Quv spinal cords increased to 2.3 times of control motor neurons. Immunoblot of Quv spinal cords revealed a relative increase in non- and hypo-phosphorylated NF-M and NF-H, and a decrease in the total amount of NFs. Quv sciatic nerves showed faintly reacted phosphorylated NF-M and NF-H. These results suggest that deficiency of assembled neurofilament results in decreased axonal transport of NFs and accumulation of NFs in cell bodies of spinal motor neurons.

Pontine atrophy in spinocerebellar ataxia type 6

To investigate the clinical range of spinocerebellar ataxia type 6 (SCA6), we screened CAG repeat expansion in the voltage-dependent alpha 1A calcium channel gene (CACNL1A4) in 71 ataxic patients in 60 families; 54 patients in 43 families with hereditary ataxia and 17 sporadic patients. Thirteen patients with SCA6 were detected to have elongated CAG in CACNL1A4. Of these, 7 patients had been diagnosed as having hereditary cerebellar cortical atrophy, and 6 patients had been found to have sporadic occurrence. One patient showed distinct pontine atrophy with prominent horizontal or oblique gaze nystagmus which is an unusual feature in sporadic olivopontocerebellar atrophy. For the efficient screening of SCA6, we would propose testing CAG repeat expansion in CACNL1A4, in patients with one of two markers: (1) horizontal or oblique gaze nystagmus without other eye movement disorders, (2) pure cerebellar atrophy, even if occurrence is sporadic. We should note that the pontine atrophy could also be caused by CAG repeat expansion in CACNL1A4.

[Hereditary ataxias in Akita prefecture]

To provide a genetic survey of hereditary ataxia, we performed PCR screening of SCA1, SCA2, MJD1 (SCA 3), SCA6, DRPLA, with 71 patients in 61 families living in Akita prefecture (1,205,571 population in 1997) in Japan. Of 71 patients in 61 families, 18 MJD1, 14 SCA6, 5 DRPLA, 1 SCA1 and 1 SCA2 patients were detected. Eighty percent of autosomal dominant inherited spinocerebellar degeneration (AD-SCD) including 7 spoladic patients genetically diagnosed as AD-SCD was MJD1 (45.7%) and SCA6 (34.3%). These suggest the prevalence rate of hereditary ataxias in Akita prefecture; 1.5 and 1.2/100,000 of MJD1 and SCA6, respectively. Only one patient of SCA1 was detected, which was frequently reported in Hokkaido and Tohoku area in Japan.

Tauroursodeoxycholic acid enhances phagocytosis of the cultured rat Kupffer cell

BACKGROUND

Ursodeoxycholic acid is used in the treatment of acute and chronic intrahepatic cholestasis because it ameliorates cholestasis and protects hepatocytes. However, few studies have examined the effect of bile acids on the function of Kupffer cells.

METHODS

The effect of various bile acids on cultured rat Kupffer cells was studied in terms of phagocytic activity in response to latex particles and morphological alterations. Video-enhanced differential interference contrast microscopy was used.

RESULTS

Taurochenodeoxycholic acid and taurodeoxycholic acid reduced the number of latex particles incorporated into Kupffer cells, but taurocholic and tauroursodeoxycholic acids enhanced phagocytosis of latex particles. Inhibition of phagocytosis by taurochenodeoxycholic acid or taurodeoxycholic acid was essentially dose dependent. Tauroursodeoxycholic acid also enhanced phagocytosis by Kupffer cells in which phagocytosis had been reduced by pretreatment with taurochenodeoxycholic acid or taurodeoxycholic acid. Incorporated latex particles had a distinct translocation speed of 0.084+/-0.024 microm/s (mean maximum speed+/-SD); the speed was in the same range with tauroursodeoxycholic acid treatment. Tauroursodeoxycholic acid induced a 56% expansion of cytoplasm, associated with increased ruffling and movement of intracellular organelles.

CONCLUSIONS

These observations suggest that tauroursodeoxycholic acid enhances membrane trafficking without changing translocation speed.

Tau expression in denervated rat muscles

We studied whether denervation affects the expression of tau, in particular phosphorylated tau, and how it is degraded in rat soleus muscles. Immunoblot analysis showed a high molecular weight, approximately 110 kDa (big tau), in normal muscle. Tau levels increased significantly in denervated muscles treated with chloroquine (a lysosomotrophic agent) and in untreated ones, as compared to levels of similarly treated contralateral, innervated muscles. Most of the tau in the innervated and denervated muscles was phosphorylated. Immunohistochemically, tau and beta-tubulin colocated in the sarcoplasm of innervated, saline-treated (intact) muscle, but the staining intensities were very weak. Both proteins, however, were expressed extensively in these areas in the denervated muscles from saline-treated rats. In the denervated muscle of chloroquine-treated rats there were numerous autophagic vacuoles in the sarcoplasm, and phosphorylated-tau accumulation was marked within these vacuoles, indicative that tau first was taken into autophagic, vacuoles by nonselective autophagy then degraded via the lysosomal as well as the nonlysosomal calpain system. Our findings suggest that phosphorylated big tau accumulates with beta-tubulin in denervated muscular atrophy, possibly in order to maintain or preserve the integrity of the muscle fiber during progressive atrophy or regeneration.

[Muscle atrophy in isolated ACTH deficiency]

We analyzed muscle area in CT and muscle pathology in a patient with isolated ACTH deficiency who started with the difficulty of elevation of both arms. Cortisol treatment resulted in full recovery from severe muscle atrophy and contracture of major joints. Change of volume of major muscles in arm, thigh and calf was followed. Major muscles were identified in CT and the area of each muscle was calculated with computer assistance. The increase of total muscle area in sequential 3 times in CT was up to 74% after prednisolone treatment. This indicates that the deficiency of cortisol resulted in 42% reduction of muscle volume. This also suggests that reduction of muscle volume induces the limitation of range of motion of shoulder joint. ATPase of muscle biopsy revealed the influence on fiber type proportion; type 1 : type 2A : type 2B = 29.6 : 6.0 : 64.4% and 35.7 : 17.6 : 46.7% in pre-treatment and post-treatment of cortisol, respectively. Mean diameters of muscle fibers in type 1, type 2A and type 2B was 41.8, 41.8, 39.1 microns and 46.2, 44.0, 37.2 microns in pre-treatment and post-treatment of cortisol, respectively. These suggest that deficiency of glucocorticoid introduces the reduction of the activity of the motor neurons innervating type 1 and type 2A muscle fibers.

Kinesin and cytoplasmic dynein in spinal spheroids with motor neuron disease

Kinesin and cytoplasmic dynein are two major molecular motors responsible for fast axonal transport. As visualized by immunohistochemistry with monoclonal antibodies, both motors were found to be distributed throughout the cell bodies, dendrites and axons of motor neurons in normal human spinal cords. Large axonal swellings, spheroids, in the spinal cords of patients with motor neuron disease showed massive accumulation of kinesin co-localized with highly phosphorylated neurofilaments. Of 114 spheroids in five spinal cords, 87% were stained heavily with the three anti-kinesin antibodies used in this study. Cytoplasmic dynein was scarce or absent in most of the spheroids. These findings suggest that kinesin selectively accumulates in the spheroids of motor neuron axons, causing disturbance of the machinery for anterograde fast axonal transport in motor neuron disease.

Kinesin accumulation in chick spinal axonal swellings with beta,beta'-iminodipropionitrile (IDPN) intoxication

Kinesin is a major molecular motor responsible for anterograde axonal transport. Chicks were injected with beta,beta'-iminodipropionitrile (IDPN) to induce axonal swellings in spinal motor neurons and spinal sensory ganglion neurons. Cylindrical swollen axons were found in the anterior horn and anterior funiculus of the spinal cord, anterior root, and spinal ganglia. All of the axonal swellings were heavily stained with two anti-kinesin monoclonal antibodies. The swellings were mildly stained with an anti-cytoplasmic dynein and anti-tubulin antibodies, and weakly stained with an anti-tau antibody. These suggest the isolated disturbance of kinesin transport with neurofilament accumulation in IDPN intoxication.

Portal-systemic encephalopathy from a spontaneous gastrorenal shunt diagnosed by three-dimensional computed tomography and treated effectively by percutaneous vascular embolization

A 67-year-old man with a portal-systemic shunt confirmed by three-dimensional computed tomography (3D-CT) was successfully treated by percutaneous vascular embolization. The patient had aggravated loss of memory, disorientation, and hyperammonemia. A gastrorenal shunt 16 mm in diameter was found by 3D-CT reconstructed by helical computed tomography (CT). Embolization was performed only in the shunt percutaneously through the inferior vena cava. One year after the embolization, no recurrence of portal-systemic encephalopathy and no portal hypertension have appeared, and the clinical course has been good.

Novel mutations of the peripheral myelin protein 22 gene in two pedigrees with Dejerine-Sottas disease

Peripheral myelin protein 22 (PMP22), a membrane glycoprotein, plays a significant role in the formation and/or maintenance of compact myelin in the peripheral nervous system. We studied two pedigrees with Dejerine-Sottas disease and identified two novel mutations in the PMP22 gene: one a 2-bp deletional mutation at nucleotide positions 426 and 427 of exon 4 (this is predicted to alter the reading frame at leucine 80 and thus to lead to frame-shifted translation), and the other a guanine to thymine substitution at nucleotide position 636 leading to a cysteine substitution for glycine 150. Both mutations were located in the putative transmembrane domains reported in many cases of Charcot-Marie-Tooth neuropathy, Dejerine-Sottas disease, and hereditary neuropathy with liability to pressure palsies. The results suggest an important role for the putative transmembrane domains of PMP22 in its function.

A multicentre randomized controlled trial of recombinant interferon-alpha-2a in the treatment of patients with chronic hepatitis C

Sixty-one chronic hepatitis C patients were randomly assigned to receive either 6 x 10(6) or 9 x 10(6) U of recombinant interferon-alpha-2a (IFN alpha-2a) six days a week for the first two weeks of treatment, followed in both cases by 6 x 10(6) U three days a week for the next 22 weeks. In the low dose group, 11 patients showed a complete response maintained for at least six months, 12 responded but then relapsed and nine did not respond; the corresponding figures in the high dose group were 10, 15 and five patients, respectively. The differences between groups are not statistically significant. Thus, this study provides no evidence of therapeutic benefit from increasing the initial dose of IFN alpha-2a. In both treatment groups, complete responders had significantly lower pretreatment viral titres than nonresponders and were significantly more likely to be infected by type 2a versus type 1b virus.

Utility of hepatitis C virus RNA levels for predicting the therapeutic efficacy of interferon

We studied the levels of serum hepatitis C virus (HCV)-RNA, the HCV genotype before interferon therapy, and the kinetics of serum HCV-RNA at the initial stages of therapy to determine their utility in predicting the therapeutic efficacy of interferon in 44 patients with chronic hepatitis C infection. We also looked at the efficacy of repeated interferon treatment in relation to the kinetics of serum HCV-RNA. The level of serum HCV-RNA determined by a branched DNA probe assay before interferon treatment and that by a reverse transcription nested polymerase chain reaction assay during the initial stages of interferon administration were useful for predicting the efficacy of treatment. Furthermore, detection of serum HCV-RNA by the reverse transcription nested polymerase chain reaction assay after the completion of interferon therapy indicated relapse at its earliest stage. In patients who experience relapse, repeated treatment with an appropriate dose of interferon before an increase in viral levels may increase the proportion of complete responses.

Pilot study of ofloxacin and interferon-alpha combination therapy for chronic hepatitis C without sustained response to initial interferon administration

A controlled trial comparing combination therapy with ofloxacin (OFLX) and interferon (IFN) versus IFN monotherapy was conducted in patients with chronic hepatitis C who failed IFN therapy. Twenty patients were assigned randomly to two groups. Equal doses of recombinant IFN alpha-2b were administered to each group for 24 weeks. For the IFN plus OFLX group, OFLX was administered for 12 weeks at a daily dose of 600 mg. Levels of hepatitis C virus RNA declined significantly from the first month after the start of IFN treatment compared with those before administration in both groups. Serum alanine aminotransferase levels were significantly lower in the IFN plus OFLX group at two and six months after the start of treatment than levels in the IFN group. The fraction of subjects whose levels of serum ALT normalized was also higher in the IFN plus OFLX group. Larger clinical trials should be undertaken.

Extension of long cellular processes of hepatic stellate cells cultured on extracellular type I collagen gel by microtubule assembly: observation utilizing time-lapse video-microscopy

Hepatic stellate cells cultured on or in freshly prepared type I collagen gel as a substratum were induced to elongate long cellular processes. The extension of the cellular processes was monitored by using video-enhanced optical microscopy. The cellular processes seemed to extend along the extracellular type I collagen fibers. Once extended cellular processes after overnight culture on type I collagen gel were retracted by cytoskeleton degradation with colchicine or cytochalasin B. The cellular processes were also retracted by treatment with protein kinase inhibitor, herbimycin A or staurosporin, or with phosphatidylinositol 3-kinase inhibitor, wortmannin. The effects of colchicine, herbimycin A, staurosporin, or wortmannin were drastic, and the cells were finally changed to a round shape within a few hours, as seen also after cold-treatment at 4 degrees C. Cytochalasin B also time-dependently retracted the extended cellular processes. These results indicated that the cultured stellate cells were induced to elongate cellular processes by cell surface binding to type I collagen fibrils, followed by protein or phosphatidylinositol phosphorylation and finally F-actin and microtubule assembly. Extended long cellular processes seem to reflect the in vivo structure of hepatic stellate cells, and molecular mechanism for the extension and maintenance of cellular processes was proposed.

Kinectin distribution in chicken nervous system

Kinectin, a major kinesin receptor on endoplasmic reticulum, was visualized with anti-kinectin monoclonal antibodies (mAbs) in the adult chicken nervous system in comparison with kinesin immunostaining. Anti-kinectin mAbs punctately stained cell bodies and proximal dendrites of motor neurons in spinal cords. Axons of motor neurons were not stained with anti-kinectin mAbs, but stained heavily with anti-kinesin mAbs. This suggest that the kinesin receptor responsible for kinesin-driven anterograde fast axonal transport is different from kinectin. Anti-kinectin mAbs strongly stained neuronal cell bodies in spinal ganglion, nuclei in brainstem, cerebellar nuclei, striatum and cerebral cortex. Small neurons in cerebellar cortex and optic lobe showed relatively weak reaction, suggesting that the amount of kinectin correlates with the size of neuronal cell bodies.

Fulminant hepatitis caused by hepatitis C virus during treatment for multiple sclerosis

A 55-year-old woman was treated at our hospital for multiple sclerosis. Therapy consisted of glucocorticosteroids and cyclosporin. In the 7th week after these drugs were discontinued the patient developed acute liver failure due to fulminant hepatitis (FH) and died. Post-mortem examination showed massive liver necrosis. Serologic examination was negative for hepatitis B virus-related markers. Antihepatitis C virus (anti-HCV) antibody and serum HCV RNA were negative on admission, but HCV RNA appeared concurrently with the onset of FH. Although HCV infection rarely causes FH, it was considered to be the cause of FH in this patient, since there were no other causes of acute liver injury. We suspect that underlying immunologic abnormalities in conjunction with HCV infection may have precipitated the FH.

Detection of heparan sulfate in spinal spheroids of beta, beta'-iminodipropionitrile (IDPN)-treated rats

Beta,beta'-Iminodipropionitrile (IDPN) is known to produce a massive accumulation of neurofilaments in the proximal portion of axons of spinal anterior horn cells. The spinal cords of 20 Wistar rats treated with IDPN were examined immunohistochemically with a monoclonal antibody against heparan sulfate (HepSS-1). Virtually all axonal swellings were intensely labeled with HepSS-1. This immunoreactivity was almost completely absorbed by the presence of CDSNS-HS (completely desulfated, N-sulfated heparan sulfate). Western blot study revealed that HepSS-1 recognized four distinct bands at the positions of approximately 17 kDa, approximately 20 kDa, approximately 21 kDa, and approximately 25 kDa. The present study suggests that the deposit of heparan sulfate in spheroids is related to the pathomechanism for the formation of axonal swelling.

Purification and characterization of cytoplasmic dynein of rabbit liver

Cytoplasmic dynein is a microtubule-dependent motor protein, which plays a role in intracellular transport. However, there have been few studies regarding the role of cytoplasmic dynein in the liver. Purification of cytoplasmic dynein from rabbit liver took advantage of the affinity of microtubule-dependent motor proteins for microtubules. Purified dynein contained heavy chain (450 kDa), intermediate chain (75 kDa), light chains (45-58 kDa) and dynactin (150 kDa). The subunit composition was consistent with previously reported data on brain cytoplasmic dynein. Microtubules prepared from bovine brain were driven by purified cytoplasmic dynein from rabbit liver, and movements of microtubules were visualized by video-enhanced differential interference contrast microscopy. The mean velocity of the motile microtubules was 1.09 +/- 0.13 microns/s. Our study provides evidence of rapid intracellular transport in hepatocytes controlled by cytoplasmic dynein.

Phosphorylation and transport of neurofilament proteins in the rat spinal ganglion

Neurofilament proteins (NFs) in rat spinal ganglia were labeled with [32P]orthophosphate injected into ganglia and analyzed by two-dimensional autoradiography and immunoblotting. Three polypeptides of NF were labeled irrespective of the extent of phosphorylation. Most of the labeled NFs were transported from cell bodies to proximal axons within 24 h. A major fraction of low phosphorylated NF-H changed to high phosphorylated form in intraganglionic nerve fibers and peripheral nerves adjacent to spinal ganglia. A small fraction of low phosphorylated NF-H appeared earlier than the high phosphorylated form in adjacent peripheral nerves, suggesting that newly synthesized NF-H in cell bodies migrate a long distance before they are extensively phosphorylated and assembled into the cytoskeleton in proximal axons.

Characterization of kinectin, a kinesin-binding protein: primary sequence and N-terminal topogenic signal analysis

Kinectin is a kinesin-binding protein (Toyoshima et al., 1992) that is required for kinesin-based motility (Kumar et al., 1995). A kinectin cDNA clone containing a 4.7-kilobase insert was isolated from an embryonic chick brain cDNA library by immunoscreening with a panel of monoclonal antibodies. The cDNA contained an open reading frame of 1364 amino acids encoding a protein of 156 kDa. A bacterially expressed product of the full length cDNA bound purified kinesin. Transient expression in CV-1 cells gave an endoplasmic reticulum distribution that depended upon the N-terminal domain. Analysis of the predicted amino acid sequence indicated a highly hydrophobic near N-terminal stretch of 28 amino acids and a large portion (326-1248) of predicted alpha helical coiled coils. The 30-kDa fragment containing the N-terminal hydrophobic region was produced by cell-free in vitro translation and found to assemble with canine pancreas rough microsomes. Cleavage of the N terminus was not observed confirming its role as a potential transmembrane domain. Thus, the kinectin cDNA encodes a cytoplasmic-oriented integral membrane protein that binds kinesin and is likely to be a coiled-coil dimer.

Heparin sulfate-like immunoreactivity in the spinal cord in motor neuron disease

The spinal cords from eight autopsy cases of sporadic motor neuron disease (MND) and two control cases were immunohistochemically examined using antibodies directed to neurofilament proteins (anti-Nf) and to heparan sulfate (HepSS-1). Variable numbers of spheroids were observed in the anterior horns in the MND cases. In one case of MND, one third to half of the remaining anterior horn cells contained conglomerate inclusions in their perikarya. These pathological structures were not encountered in the control cases. The immunohistochemical study revealed that both anti-Nf and HepSS-1 intensely labelled all spheroids and conglomerate inclusions in the MND cases. The colocalization of heparan sulfate with neurofilamentous accumulation suggests that heparan sulfate is required for the aggregation of neurofilaments, resulting in the formation of spheroids and conglomerate inclusions in MND.

Hereditary lipo-muscular atrophy with joint contracture, skin eruptions and hyper-gamma-globulinemia: a new syndrome

We previously reported two siblings with decreased subcutaneous adipose tissue, muscular atrophy, joint contractures, recurrent skin eruptions, hyper-gamma-globulinemia, and reduced natural killer cell activity. Some of their clinical features are similar to those of partial lipodystrophy, but they are distinct in that muscular atrophy, joint contractures and recurrent skin eruptions are not found in patients with partial lipodystrophy. Thirteen other Japanese patients with similar clinical manifestations have been reported. We propose that such cases should be considered a distinct clinical entity.

Kinesin and cytoplasmic dynein binding to brain microsomes

Movement of cellular organelles in a directional manner along polar microtubules is driven by the motor proteins, kinesin and cytoplasmic dynein. The binding of these proteins to a microsomal fraction from embryonic chicken brain is investigated here. Both motors exhibit saturation binding to the vesicles, and proteolysis of vesicle membrane proteins abolishes binding. The maximal binding for kinesin is 12 +/- 1.7 and 43 +/- 2 pmol per mg of vesicle protein with or without 1 mM ATP, respectively. The maximal binding for cytoplasmic dynein is 55 +/- 3.8 and 73 +/- 3.7 pmol per mg of vesicle protein with or without ATP, respectively. These values correspond to 1-6 sites per vesicle of 100-nm diameter. The nonhydrolyzable ATP analog, adenyl-5'-yl imidodiphosphate (AMP-PNP), inhibited kinesin binding to vesicles but increased kinesin binding to microtubules. An antibody to the kinesin light chain also inhibited vesicle binding to kinesin. In the absence but not presence of ATP, competition between the two motors for binding was observed. We suggest that there are two distinguishable binding sites for kinesin and cytoplasmic dynein on these organelles in the presence of ATP and a shared site in the absence of ATP.

Kinectin, a major kinesin-binding protein on ER

Previous studies have shown that microtubule-based organelle transport requires a membrane receptor but no kinesin-binding membrane proteins have been isolated. Chick embryo brain microsomes have kinesin bound to their surface, and after detergent solubilization, a matrix with an antibody to the kinesin head domain (SUK-4) (Ingold et al., 1988) bound the solubilized kinesin and retained an equal amount of a microsome protein of 160-kD. Similarly, velocity sedimentation of solubilized membranes showed that kinesin and the 160-kD polypeptide cosedimented at 13S. After alkaline treatment to remove kinesin from the microsomes, the same 160-kD polypeptide doublet bound to a kinesin affinity resin and not to other proteins tested. Biochemical characterization localized this protein to the cytoplasmic face of brain microsomes and indicated that it was an integral membrane protein since it was resistant to alkaline washing. mAbs raised to chick 160-kD protein demonstrated that it was absent in the supernatant and concentrated in the dense microsome fraction. The dense microsome fraction also had the greatest amount of microtubule-dependent motility. With immunofluorescence, the antibodies labeled the ER in chick embryo fibroblasts (similar to the pattern of bound kinesin staining in the same cells) (Hollenbeck, P. J. 1989. J. Cell Biol. 108:2335-2342), astroglia, Schwann cells and dorsal root ganglion cells but staining was much less in the Golgi regions of these cells. Because this protein is a major kinesin-binding protein of motile vesicles and would be expected to bind kinesin to the organelle membrane, we have chosen the name, kinectin, for this protein.

[A new autoantibody, anti-210kDa microtubule associated protein antibody, detected in the serum of patients with various liver diseases and SLE]

A new autoantibody to 210kDa microtubule associated protein (MAP) obtained from rabbit liver excrude was detected in the serum with various liver diseases and SLE. As there were no reports concerning autoantibodies to MAPs in animals and human, it may say that anti-210kDa MAP autoantibody we detected was a new cytoskeleton antibody. Using western blotting method, the anti-210kDa MAP autoantibody was frequently found in the patients with alcoholic liver diseases (52.5%), PBC (55.6%), autoimmune hepatitis (83.3%), SLE (71.4%) but rarely in the patients with viral liver diseases (26.4%) and none in normal controls at a serum dilution of 1:10. In addition, at a serum dilution of 1:100, the anti-210kDa MAP autoantibody was found in the patients with alcoholic liver diseases (22.5%), PBC (44.4%), autoimmune hepatitis (66.7%), SLE (71.4%), viral liver diseases (17.0%) and none in normal controls. It was confirmed that the anti-210kDa MAP autoantibody was frequently detected in cases of alcoholic liver diseases, PBC, autoimmune hepatitis and SLE than in those of viral liver diseases and normal control.

Three-step purification method and characterization of the bovine brain 90-kDa heat shock protein

A protein that cross-reacted with antibody against the 90-kDa heat shock protein (HSP90) of a mouse lymphoma cell line was purified from bovine brain by three steps. Fifty milligrams of the 90-kDa protein was recovered from 350 g of the brain cortex. The sedimentation coefficient and Stokes radius of the purified protein were 6.0 s and 6.7 nm, respectively. The molecular weight was calculated to be 170,000. The molecule was composed of two identical 90-kDa subunits. A partial amino acid sequence (23 residues) of this protein was homologous (96%) to human HSP90 (the sequence of 174-196). These facts led to the identification of the 90-kDa brain protein with HSP90. In bovine tissues, the brain contained this protein at a remarkably high concentration. The brain HSP90 was separable from glucocorticoid receptor by heparin-agarose and DNA-cellulose columns. It is concluded that HSP90 is present in brain cytosol and mostly as free molecules. Immunohistochemical studies showed that the protein was localized in nerve excitable cells. It was not found in nuclei but in cytosol.

Suppressive effect of E-64c on ischemic degradation of cerebral proteins following occlusion of the middle cerebral artery in rats

Microtubule-associated protein 2 (MAP2) levels in the left cerebral hemisphere decreased significantly 3 days after occlusion of the left middle cerebral artery in rats to 29 +/- 16.3% of control levels. Since MAP2 is one of the substrates of calpain, E-64c, a synthetic calpain inhibitor, was administered at a dose of 400 mg/kg twice a day for 3 days, with the first dose being given before the production of ischemia. This depletion was significantly inhibited in vivo by E-64c (P less than 0.05) to increase MAP2 levels to 55 +/- 25.7% of control levels. E-64c had no significant effect on the ischemia-induced depletion of myelin-associated glycoprotein. Sham-operated rats were used as controls. Our results suggest that calpain is partially involved in the degradation of MAP2, and that the use of calpain inhibitors can be a useful clinical approach to cerebral ischemia.

Changes in the concentrations of cerebral proteins following occlusion of the middle cerebral artery in rats

Using an immunoblotting technique, we investigated changes in the concentrations of microtubule-associated protein 2, 200-kDa neurofilament, tubulin, myelin-associated glycoprotein, and 2':3'-cyclic nucleotide 3'-phosphodiesterase in the brains of 40 rats following occlusion of the left middle cerebral artery or sham operation. Compared with those 4 hours after surgery, concentrations of all proteins decreased significantly in the left hemisphere 3 days after surgery (p less than 0.01). Microtubule-associated protein 2 was the most susceptible to ischemia, and its mean +/- SEM concentration decreased to 23 +/- 9.4% of that in concurrent sham-operated controls. Degradation products of microtubule-associated protein 2 and myelin-associated glycoprotein were detected on the blots. Furthermore, in the contralateral hemisphere (where calpain might be activated), concentrations of these two proteins decreased to 57 +/- 12.0% and 83 +/- 4.3% of those in concurrent sham-operated controls, respectively, 3 days after surgery. Changes in the concentrations of cerebral proteins in the contralateral hemisphere are important for understanding clinical symptoms not attributable solely to the ipsilateral lesion following a focal cerebral stroke.

Detection and isolation of a 30 kDa abnormal protein in avian dystrophic muscle

We have studied the protein composition of the pectoralis superficialis muscle of genetically dystrophic (New Hampshire line 413) and normal control (line 412) chickens by one- and two-dimensional gel electrophoresis. A protein, referred to hereafter as the 30 kDa abnormal protein, was specifically detected in the affected muscle. It was purified to homogeneity, and its molecular properties were studied. It is a monomer with a molecular mass of approximately 30 kDa and an isoelectric point of about pI 8.4. We have screened by Western blotting a variety of muscles from line 412 and line 413 chickens for the presence of the 30 kDa protein. While the pattern of total protein is very similar in all cases, the 30 kDa protein was not detected in the pectoralis superficialis muscle of line 412 chickens. However, the immunoreactive bands were detected in the sartorius muscle and the tensor fasciae latae muscle from dystrophic and normal chickens. Interestingly, the immunoreactive bands of normal skeletal muscles are smaller in molecular weight than those of dystrophic skeletal muscles. To determine the early time sequence of the appearance of the abnormal protein, we studied muscles from embryos and post-hatched chickens at various ages. The abnormal protein was detected in dystrophic muscles as early as 15 days ex ovo and occurred throughout development up to six months ex ovo. Although the implication of the dystrophy-associated appearance of the 30 kDa protein in the affected muscle is not clear at present, it would be of particular interest to elucidate the biochemical functions of the 30 kDa protein in the affected muscle (pectoralis superficialis muscle) of genetically dystrophic chicken.

[Studies of microtubule associated proteins in the liver--isolation of a 210 kDa microtubule associated protein from rabbit liver]

The biochemical characteristics and cellular localization of microtubule associated proteins (MAPs) were studied using rabbit liver. The MAPs fraction, isolated from rabbit liver crude extract by a modification of Vallee's method, consisted of several proteins, as identified by SDS-polyacrylamide gel electrophoresis. The most prominent of these was a 210 kDa protein (rabbit 210 kDa MAP). The molecular weight of rabbit 210 kDa MAP was distinct from that of the major brain MAPs, MAP1, MAP2 and Tau, isolated from rabbit brain crude extract by same method. Monoclonal antibodies (mAb) to this rabbit 210 kDa MAP were raised. Using immunoblotting method, we confirmed that anti-rabbit 210 kDa MAP mAb reacted to 210 kDa protein from rabbit liver excrude, while this mAb also reacted to 210 kDa protein from rabbit brain excrude. Immunofluorescent staining using fixed rabbit liver was carried out using these mAb. In frozen sections of the rabbit liver, the antigen related to mAb 7B10 was localised in the hepatic cells and epithelial cells of the bile duct but not in the smooth muscle cells and endothelial cells.

Phosphorylation of neurofilament proteins and localization of axonal swellings in motor neuron disease

Seven lumbosacral spinal cords with motor neuron disease were examined immunocytochemically with monoclonal antibodies (MAb) directed against neurofilament proteins (NFP). Each of the 5 MAbs used in this study was monospecific to one of the triplet of NFP. Two of them were specific to the highly phosphorylated form of high molecular weight peptide of NFP (NFP-H). All 5 MAbs stained all axonal swellings examined. In 2 spinal cords examined, some axonal swellings were found in the anterolateral funiculus and some of these were as far as 1000 microns from the grey matter. This localization of axonal swellings suggests that a high degree of phosphorylation of NFP is not the cause of accumulation of NFP in axonal swellings in motor neuron disease.

Serum antibodies to brain proteins in a patient with parkinsonism associated with IgM paraproteinemia

We report a 58 year-old man with various neurological symptoms as parkinsonism, autonomic dysfunction, mental deterioration and lower motor neuron involvement associated with IgM gammopathy whose serum showed antibody activities to human brain proteins. His serum reacted with 156kDa protein from substantia nigra and 130kDa of cerebral cortical grey matter, cerebellar cortex, putamen, thalamus or pallidum by immunoblotting method. The serum of this patient reacted with proteins widely distributed in the central nervous system, and this antibody in his serum might be the cause of his various neurological symptoms.