Biomedical subjects

H Miyasaka

Publications and source records attributed to H Miyasaka.

At least 37 records · Page 2Linked to original sources

PubMed1999

[Morphological changes in the stria vascularis and hair cells after mastoid-vibration using a cutting bur].

Severe sesorineural deafness develops occasionally after tympanoplasty. Since a vibration induced by the drill during surgery is thought to be one of the cause, we examined its effect on the inner ear in this study. Five guinea pigs aged about 1 month were used. The right ear of each animal was used as the control, and the left ear underwent stimulation with the drill induced vibration. The vibration was applied to the temporal bone for 60 seconds using a cutting bur. After the vibration, the stria vascularis and hair cells in the cochlea were examined. For the investigation of the permeability of the stria vascularis, horseradish peroxidase (HRP) was injected intravenously as a tracer, and the tissue was observed with a light and an electron microscopes. Three sections of the stria vascularis from each of the superior turn (the third turn) and the inferior turn (the basal turn) of bilateral cochleae were randomly prepared, and they were classified into Types I to IV according to the degree of HRP leakage. When a hair cell had even one vacuole inside, it was classified as a vacuole-positive cell. After stimulation with the drill-induced vibration, about 10% of the blood vessels of the stria vascularis showed severe leakage of HRP (Types III, IV). In the intermediate cells, partial degeneration of mitochondria was found. No significant difference in the permeability of the blood vessels was found between the turns. The route of leakage of HRP from blood vessels of the stria vascularis was neither the transport via pinocytotic vesicle nor passage through the intercellular space of endothelial cells. The leakage through a tubular-like structure in the endothelial cells was observed. Since no HRP was found in this tubular-like structure ordinarily, a channel might have been opened by injury due to the vibration. The leakage from the blood vessels of the stria vascularis in the control side could scarcely be observed. Many hair cells in the drill-stimulation side in both the first and the third turns showed vacuoles with loss of intracellular structure. Slight loss of auditory hairs was found in this study, suggesting that the development of a vacuole was the first reaction to the drill-stimulation. Since the sensitivity toward stimulation of the drill-induced vibration was different among individual animals, it appears possible that the inner ear is injured in some cases without direct touch to the auditory ossicles owing to technical failure.

Animals↗

PubMed1998

A novel plasmid recombination mechanism of the marine cyanobacterium Synechococcus sp. PCC7002.

We describe a novel mechanism of site-specific recombination in the unicellular marine cyanobacterium Synechococcus sp. PCC7002. The specific recombination sites on the smallest plasmid pAQ1 were localized by studying the properties of pAQ1-derived shuttle-vectors. We found that a palindromic element, the core sequence of which is G(G/A)CGATCGCC, functions as a resolution site for site-specific plasmid recombination. Furthermore, site-directed mutagenesis analysis of the element show that the site-specific recombination in the cyanobacterium requires sequence specificity, symmetry in the core sequence and, in part, the spacing between the elements. Interestingly, this element is over-represented not only in pAQ1 and in the genome of the cyanobacterium, but also in the accumulated cyanobacterial sequences from Synechococcus sp. PCC6301, PCC7942, vulcanus and Synechocystis sp. PCC6803 within GenBank and EMBL databases. Thus, these findings strongly suggest that the site-specific recombination mechanism based on the palindromic element should be common in these cyanobacteria.

Cyanobacteria↗

PubMed1998

Nucleotide sequence of plasmid pAQ1 of marine cyanobacterium Synechococcus sp. PCC7002.

We have determined the complete nucleotide sequence of pAQ1, the smallest plasmid of the unicellular marine cyanobacterium Synechococcus sp. PCC7002. The plasmid consists of 4,809 bp and has at least four open reading frames that potentially encode polypeptides of 50 or more amino acids. We found that a palindromic element, the core sequence of which is G(G/A)CGATCGCC, is over-represented not only in plasmid pAQ1 but also in the accumulated cyanobacterial genomic sequences from Synechococcus sp. PCC6301, PCC7002, PCC7942, vulcanus and Synechocystis sp. PCC6803 within GenBank and EMBL databases. It suggests that this sequence might mediate gene rearrangement, thus increasing genetic diversity, since recombination events are frequent in cyanobacteria.

Amino Acid Sequence↗

PubMed1998

Compilation of mRNA sequences surrounding the AUG translation initiation codon in the green alga Chlamydomonas reinhardtii.

Sequences of 118 mRNAs of the green alga Chlamydomonas reinhardtii in the GenBank data base were compiled to examine the consensus sequence surrounding the AUG translation initiation codon. The consensus sequence for C. reinhardtii was found to be gc(A/C)A(A/C)(A/C) AUGGC. The AUG context of chloroplast proteins (nuclear coded) and non-chloroplast proteins were compared by a separate compilation, and some distinctive features in AUG context of chloroplast proteins were found.

Algal Proteins↗

PubMed1998

[Chronic progressive radiation myelopathy after bone marrow transplantation].

Two patients after bone marrow transplantation (BMT) developed chronic progressive radiation myelopathy (CPRM). The factors contributing to development of CPRM at the low dose, which radiation doses given for enlarged regional lymph nodes prior to BMT ordinarily would be too low to induce CPRM, were discussed, and clinicoradiologic correlations in CPRM from onset through the stabilized state examined. The clinicoradiologic findings of two patients, who are a 26-year-old man with malignant lymphoma (autologous BMT) performed radiotherapy totaling 20 Gy for enlarged regional lymph nodes before BMT, and a 40-year old woman with chronic myeloid leukemia (allogenic BMT) done 18.9 Gy, were examined. The involved spinal cord segments were irradiated for lymph node enlargement prior to BMT, and all the clinicoradiologic findings were consistent with CPRM. We considered possible synergistic toxicity with high-dose busulfan accompanying BMT. Unlike the second case, the first patient had continued severe progression of CPRM, possibly because a higher dose of additional radiotherapy (30 Gy) was given for presumed spinal cord tumor involvement in that case than in the other (< 20 Gy). These cases demonstrate that BMT protocols carry a risk of potentiating the spinal cord toxicity of low-dose radiotherapy.

Adult↗

PubMed1997

[Multifocal choroiditis with subretinal fibrosis].

We report 2 cases of multifocal choroiditis associated with subretinal fibrosis on whom the fluorescein fundus angiography (FAG) and the indocyanine green infrared angiography (IA) were performed. Case 1 was a moderately myopic 14-year-old girl who had no ocular symptoms. She had numerous small, round, discrete, partially conflued lesions with subretinal fibrosis scattered in the periphery and one discrete relatively large lesion along the superotemporal arcade in her left fundus. Subretinal fibrosis had progressed in the superior lesion. Some lesions had coalesced into a sword-like pattern over a period of 2 years. Case 2 was a high myopic 18-year-old man who had distorted vision in his right eye. He had some small whitish round lesions with one small choroidal neovascular tissue and subretinal fibrosis in the posterior pole and a sword-like lesion in the inferior periphery. Another choroidal neovascular tissue developed near the macula during the 6-month follow-up period. In FAG, the centers of the lesions hypofluoresced corresponding to the pigmentation and the edges hyperfluoresced. Some of the lesions showed window-defects and others tissue-staining. In IA, all the whole lesions hypofluoresced from an early stage of the angiography and some major choroidal vessels were visible through them. The hypofluorescent areas persisted into the late phase. The hypofluorescent areas of the IA were larger than those seen in FAG and in funduscopy. These findings indicate that the choriocapillaris was initially damaged and consequently the structures of the lesions partly disappeared at the level of the retinal pigment epithelium-choriocapillaris complex.

Adolescent↗

PubMed1997

[A case of superficial siderosis of the central nervous system with bilateral vestibular dysfunction].

A 58-year-old woman developed slowly progressive hearing loss, anosmia, and unsteady gait. She had neither repeated episode of headache nor a past history of neurosurgical operation or head injury. Neurological examination revealed anosmia, moderate degree of sensorineural hearing loss. She showed loss of caloric response bilaterally. No nystagmus was found. Romberg sign was present. No cerebellar ataxia was noted in the finger-to-nose or the heel-to-knee test. No adiadochokinesis was noted. Deep tendon reflexes were increased in both upper and lower extremities. Sensation was intact. She showed disturbance of the righting reflex in the tilt-table examination. CSF were under normal pressure, xanthochromic with siderophages. CSF total protein and ferritin level were elevated. T2-weighted image (TE4000/TR100) of high field strength magnetic resonance imaging (MRI) showed marginal hypointensity of the brain stem, the Sylvian fissures, the tips of temporal lobes, anterior cerebellar surfaces and the entire spinal cord. Angiography of the cerebral vessels and spinal arteries failed to identify the source of bleeding. It seemed likely that she had lost bilateral vestibular and auditory functions caused by hemosidelin deposition to her eighth nerves which are often affected by this disorder. Her disturbance of gait and station was apparently similar to cerebellar ataxic gait, however, she did not have limb ataxia. The electronystagmogram revealed marked degree of vestibular dysfunction (VOR) and relative sparing of cerebellar function (OKN). Her disturbance of the righting reflex in the tilt-table examination and the characteristic feature of her Romberg sign with directional preponderance also indicate that the bilateral loss of vestibular functions, i.e., vestibular ataxia caused her dysequilibrium syndrome. It is our impression that vestibular ataxia might precede cerebellar ataxia commonly reported so far.

Brain↗

PubMed1996

[A 78-year-old man with young onset parkinsonism and sudden death].

We report a right-handed 78-year-old man with early onset parkinsonism. The patient had an onset of micrographia at 23 years of the age in 1939. Seven years later he started to drag his right foot, and at 38 years of age, he walked with small steps with festination. Tremor was also present in his right hand. His daily life was independent as a otorhinolaryngologist. He visited our clinic on March 24, 1977 when he was mentally sound and showed mild parkinsonism consisting of masked face, stooped posture, small step gait, bradykinesia, and right side dominant rigidity and tremor. He showed good response to trihexyphenidyl and amantadine HCl. Two month later, he developed dyskinesia and some worsening of parkinsonism, and was admitted to our hospital for the first time. He was treated with 400 to 600 mg/day of levodopa/ carbidopa. He showed marked improvement, however, dyskinesia remained in his mouth. He was doing well until 77 years of age (June of 1993) when he developed hallucination and motor fluctuations. He was admitted again to our hospital on June 22, 1993. On admission, he was alert and appeared mentally sound. However, Hasegawa dementia scale was 18/30. Upward gaze was slightly restricted (3/5). Voice was somewhat small but no masking was noted. His posture was stooped and the gait was of small step. Dyskinesia was noted during walk. No rigidity nor tremor was noted. Deep tendon reflexes were lost but no sensory loss or motor weakness was noted. Routine laboratory studies were unremarkable. A cranial CT scan revealed only mild to moderate cortical atrophy. Motor and sensory conduction velocities were within normal limits, however, motor action potentials could not be obtained with stimulation to the right common peroneal nerve. He was treated with 600 mg/day of levodopa with carbidopa, 100 mg of amantadine HCl, 300 mg of Dops, and 25 mg of tiapride. He continued to show motor fluctuations, and was discharged on July 23, 1993. Since then his motor functions had become progressively worse with frequent falls, but he was still able to walk without support. On October 3 of 1994, he went to bed as usual. On the next morning, he was found dead in his bed at 9: 30. The patient was discussed in neurological CPC, and the chief discussant arrived at the conclusion that the patient had young-onset Parkinson's disease with Lewy bodies in the substantia nigra. Opinions were divided between Parkinson's disease and Lewy body negative young onset parkinsonism. Postmortem examination revealed obstruction of the trachea by aspirated foods, and the cause of death appeared to have been suffocation by the foods. Macroscopically, the external appearance of the brain was unremarkable except for slight frontal atrophy. The substantia nigra showed depigmentation in the lateral part, but the pigmentation of the medial part was well preserved. Upon histologic examination, the number of pigmented neurons in the dorsomedial part was well preserved. In the lateral part, pigmented neurons were well preserved in the dorsal area, however, in the ventral area, only non-pigmented neurons were seen; they appeared to be neurons in the pars reticulata. No gliosis was seen in any of the nigral areas. No Lewy bodies were seen in the remaining neurons. So-called immature neurons with rounded shape without neuromelanin could not be detected. The locus coeruleus neurons were well preserved. The putamen and the other basal ganglia structures were also intact. Slight myelin pallor was noted in the subcortical white matter, however, otherwise cerebral cortices were normal. The histology of this patient is unique in that only the ventrolateral part of the substantia nigra showed abnormal finding consisting of lack of pigmented neurons without gliosis. It is not clear whether the nigral change represents degeneration or a congenital "hypoplasia'. To our knowledge, such a unique pathology of the substantia nigra has not been reported in the literature. Our patient ma

Age of Onset↗

PubMed1996

[Therapeutic keratoplasty using corneas obtained from keratoconus patients].

Therapeutic lamellar keratoplasty was performed using corneas obtained from keratoconus patients undergoing penetrating keratoplasty. The corneas used in this series were stored in preservation solution for 7 to 59 days (average, 27.8 days) and submitted to surgery. The recipients were three patients with recurrent pterygium, one with primary pterygium, one with corneal perforation and iris prolapse due to fungal corneal ulcer, and one with limbal dermoid. Graft rejection developed in two cases postoperatively, but they were successfully treated with steroid therapy. During the entire period of clinical observation, there was no sign of recurrence of pterygium. In the case of the fungal corneal ulcer, the site of perforation healed quickly and the donor cornea maintained its transparency. A marked cosmetic improvement was achieved in the case of the limbal dermoid. Obtaining corneas from keratoconus patients and storing them for a short period is a potentially useful application for therapeutic lamellar keratoplasty.

Adult↗

PubMed1995

[Surgical and botulinum toxin treatment in two cases of abnormal retinal correspondence-exotropia with congenital homonymous hemianopsia].

We report 2 unusual cases of congenital occipital hemianopsia associated with abnormal retinal correspondence (ARC)-exotropia. Two Japanese males, 25 and 28 years of age, visited our hospital for surgical correction of manifest exotropia with dissociated vertical deviation and overaction of the superior oblique muscle. Visual field examination demonstrated homonymous hemianopsia with approximately 5 to 10 degrees of macular sparing. Visually evoked potential examination showed small amplitude similar to dissociated vertical deviation patients in all half-field stimulation. Electrooculogram examination demonstrated defective pursuit to the ipsilateral side. Some investigators have speculated that progressive exotropia compensates for homonymous hemianopsia and is a rare contraindication for strabismus surgery. To confirm the deterioration of motor and visual functions before surgery in these patients, we tried injections of botulinum A type toxin into the lateral rectus muscle ipsilateral to the hemianopsia. Contrary to the hypothesis, our patients had no change in their binocular visual fields and visual function. Finally, we performed recession of the lateral rectus muscle, so that both patients were satisfied with their ocular alignment, with no marked change of visual behavior.

Adult↗

PubMed1995

[Treatment of sclero-corneomalacia after cataract surgery].

We treated sclero-corneomalacia in an 84-year-old woman, which occurred 7 months after cataract surgery on her left eye. Since medical therapy could not prevent progress of the sclero-corneal lesion and perforation of the eyeball was likely, we performed implantation of preservable sclera and keratoepithelioplasty. The patient has an uneventful postoperative course without recurrence and good visual acuity was preserved. To minimize the post-operative inflammation and early reform of the ocular surface, implantation of preservable sclera and keratoepithelioplasty is an effective procedure.

Aged↗

PubMed1995

Fluorescence properties of quinacrine- and spin-labelled oligodeoxynucleotide.

Oligodeoxynucleotides involving a stable nitroxide radical, 5-(2,2,5,5-tetramethyl-3-ethynylpyrroline-1-oxyl)-2-deoxyuridine residue (TMP), and a fluorescence dye, quinacrine (Qu), on each complementary strand and those on the same strand in the duplexes were prepared. Three base-pair units locate between TMP and Qu. The interaction between TMP and the excited singlet Qu has been studied by picosecond transient absorption spectroscopy and fluorometry. From the biphasic fluorescence decay profile, it was suggested that there exist two sites of the dye in the oligodeoxynucleotide with the modifiers in the different complementary strands. In addition, no effective fluorescence quenching was observed for this oigodeoxynucleotide. On the other hand, the triphasic fluorescence decay profile was observed for the oligodeoxynucleotide having Qu and TMP in the same strand and the fluorescence was slightly quenched. Picosecond transient absorption spectroscopy revealed that the enhanced intersystem-crossing by TMP was responsible for the quenching of the fluorescent state of the dye. From these results, it has been concluded that the role of the DNA duplex in the quenching process of the dye by TMP was rather small.

Fluorescent Dyes↗

PubMed1994

[A 65-year-old woman with headache, facial pain, and progressive multiple cranial neuropathy].

We report a 65-year-old woman with progressive multiple cranial neuropathy. She had been suffered from bronchial asthma since 1979 for which prednisolone had been prescribed. She noted an onset of pain around her nose in October, 1989, which extended into the periorbital regions bilaterally. In February, 1990, she was treated with stellate ganglion block and trigeminal nerve block; these treatments partially alleviated her pain. In May of 1991, she noted a difficulty in swallowing solid foods. In November of the same year, she developed right facial paresis; two weeks later, she noted numbness in her left face, and was hospitalized to our service on December 16, 1991. On admission, she was afebrile and general physical examination was unremarkable except for piping rales in her both lung fields. On neurologic examination, she was alert and oriented to all spheres; higher cerebral functions were intact. In the cranial nerves, her olfactory sense was lost bilaterally; her vision was markedly diminished bilaterally only to recognize hand movements; the optic fundi appeared normal; the pupils were isocoric and reacted to light promptly. The extraocular muscles were moderately weak to most of the directions more on the left; no nystagmus was present. Facial sensation was diminished bilaterally; the jaw deviated to right; right facial paresis of peripheral type was present; her hearing was diminished bilaterally more on the right. The movement of the soft palate was diminished on the right side; dysphagia was present; her voice was horse; the gag reflex was diminished. The sternocleidomastoid muscle was weak bilaterally; the tongue appeared normal. Examination of gait was differed because of headache, however, no apparent motor weakness was present. No ataxia or involuntary movement was noted. Deep reflexes were normally elicited and symmetric. Plantar response was flexor. Sensation in the extremities was intact. Kernig's sign was positive at 70 degree leg extension; eyeball tenderness was also present bilaterally, however, no nuchal stiffness was noted. Following abnormalities were present in the laboratory examination: WBC 11,400/microliters, ESR 50 mm/hr, CRP 6.1 mg/dl. The lumbar CSF was under a normal pressure containing 29 WBC/microliters (neutrophils 7, lymphocytes 20, others 2), 67 mg/dl of protein, and 53 mg/dl of sugar; cultures for acid-fast bacilli as well as for other bacteria were negative; no malignant cells were found. A cranial CT scan revealed an isodensity mass in the orbit and ill-defined low density areas in the white matters of the frontal lobes.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗

PubMed1994

[Characteristic event-related potentials evoked by somatosensory tasks in a patient with right-left disorientation and finger agnosia].

Event-related brain potentials associated with both somatosensory and auditory detection tasks were recorded from the scalp in a 63-year-old man with finger agnosia and right-left disorientation resulted from cerebral infarction located around the region of the left angular gyrus. In a somatosensory oddball paradigm for discrimination between the right index finger (target, P = 0.2) and the left index finger (non-target, P = 0.8), early cognitive components P100, N140 and processing negativity were observed both in the target responses and non-target responses, however, no P300 component was recorded in both paradigms. In another paradigm to discriminate the index finger (target, P = 0.2) from small finger (non-target, P = 0.8) in the right hand, no P300 was evoked and only processing negativity was recorded both in the target responses and nontarget responses. These phenomena were obtained through characteristic behavior that the patient paid attention to the target stimuli as well as non-target stimuli and mentally counted them without discrimination. In contrast, in an auditory oddball paradigm P300 was clearly demonstrated to target stimuli that the patient correctly could count. The normal appearance of P300 in auditory detection tasks strongly suggests that the neural generator for the P300 was reserved intact. These results indicate that somatosensory information processing might be disturbed at the level of sensory discrimination needed for generation of P300 in our patient. It is also proposed that the neural events for somatosensory discrimination and auditory discrimination would take separate channels each other to reach the common generator of p300 in information processing.

Brain↗

PubMed1994

Molecular cloning and expression of cDNAs encoding two isoforms of protein phosphatase 2C beta from mouse testis.

Two isoforms of protein serine/threonine phosphatase were isolated and sequenced from mouse testis. A deletion of 48 nucleotides of PP2C beta 4 cDNA in comparison with PP2C beta 3 cDNA resulted in different COOH-terminal sequences of 12 and 15 amino acids, respectively. These COOH-terminal sequences of PP2C beta 3 and PP2C beta 4 were further found to be different from those of isoforms MPP beta 1 and MPP beta 2 of mouse PP2C beta reported (Terasawa, et al. Arch. Biochem. Biophys. 307: 342-349, 1993). The common sequence of 378 amino acids from these four isoforms of mouse PP2C beta exhibited 95% identity with the corresponding sequence of rat PP2C beta. The mRNAs of approximately 2.0 Kb for PP2C beta 3 and PP2C beta 4 were expressed only in testis, while the mRNAs of 3.3 Kb and 8.5 Kb for MPP beta 1 and MPP beta 2, respectively, were found in somatic tissues.

Amino Acid Sequence↗

PubMed1993

Interaction of the tail domain of high molecular weight subunits of neurofilaments with the COOH-terminal region of tubulin and its regulation by tau protein kinase II.

We previously showed that neurofilaments interact with microtubules (MTs) via their high molecular weight subunits (NF-H) after alkaline phosphatase treatment. Here we studied the effects of phosphorylation of NF-H on this interaction. tau protein kinase II, Ser/Thr protein kinase, phosphorylated NF-H in the tail domain, decreased its electrophoretic mobility to a native level, and also restored its property to be less interactive with MTs. Phosphorylation by cAMP-dependent protein kinase caused no shift of electrophoretic mobility or dissociation from MTs. We conclude that the tail domain of NF-H directly interacts with the MT surface, and the interaction is regulated via phosphorylation of the tail domain of NF-H by Ser/Thr protein kinase like tau protein kinase II. To characterize the binding domain of NF-H on MTs, subtilisin digestion of MTs and competition analysis with the MT binding fragment of tau protein were performed. The dissociation constant of NF-H to subtilisin MTs was higher than that to intact MTs. The maximum binding of NF-H was reduced when tau fragments existed. These results revealed that the COOH-terminal region of tubulin is involved in the binding to NF-H, and the NF-H and microtubule-associated protein binding domains are closely apposed on the surface of MTs.

Animals↗

PubMed1993

Molecular cloning and expression of mouse and human cDNA encoding AES and ESG proteins with strong similarity to Drosophila enhancer of split groucho protein.

Mouse and human cDNA encoding AES (amino-terminal enhancer of split) and ESG (enhancer of split groucho) proteins with strong similarity to Drosophila enhancer of split groucho protein were isolated and sequenced. Mouse AES-1 and AES-2 proteins, probably resulting from alternative splicing, contain 202 and 196 amino acids, respectively, while mouse ESG protein consists of 771 amino acids. The amino acid sequences of mouse and human AES proteins were found to exhibit approximately 50% identity to the amino-terminal region of Drosophila groucho, mouse ESG and human transducin-like enhancer of split (TLE) proteins. Mouse AES transcripts of 1.5 kb and 1.2 kb were abundantly expressed in muscle, heart and brain. Human AES transcripts of 1.6 kb and 1.4 kb were predominantly present in muscle, heart and placenta. Mouse ESG (homolog of human TLE 3) transcripts of 3.3 kb and 4.0 kb were found only in testis, while human TLE 1 transcripts of 4.5 kb was more abundant in muscle and placenta compared to heart, brain, lung, liver, kidney and pancreas. Human AES, TLE 1 and TLE 3 genes were mapped to chromosomes 19, 9 and 15, respectively, using human and Chinese hamster hybrid cell lines.

Amino Acid Sequence↗

PubMed1993

Dynamics of the neuronal intermediate filaments.

We have analyzed the dynamics of neuronal intermediate filaments in living neurons by using the method of photobleaching of fluorescently-labeled neurofilament L protein and immunoelectron microscopy of incorporation sites of biotinylated neurofilament L protein. Low-light-level imaging and photobleaching of growing axons of mouse sensory neurons did not affect the rate of either axonal growth or the addition of intermediate filament structures at the axon terminal, suggesting that any perturbations caused by these optical methods would be minimal. After laser photobleaching, recovery of fluorescence did occur slowly with a recovery half-time of 40 min. Furthermore, we observed a more rapid fluorescence recovery in growing axons than in quiescent ones, indicating a growth-dependent regulation of the turnover rate. Incorporation sites of biotin-labeled neurofilament L protein were localized as numerous discrete sites along the axon, and they slowly elongated to become continuous arrays 24 h after injection. Collectively, these results indicate that neuronal intermediate filaments in growing axons turn over within the small area of the axoplasm possibly by the mechanism of lateral and segmental incorporation of new subunits.

Animals↗