Biofilm Spreading by the Adhesin-Dependent Gliding Motility of Flavobacterium johnsoniae: 2. Role of Filamentous Extracellular Network and Cell-to-Cell Connections at the Biofilm Surface.

Flavobacterium johnsoniae forms a thin spreading colony on nutrient-poor agar using gliding motility. As reported in the first paper, WT cells in the colony were sparsely embedded in self-produced extracellular polymeric matrix (EPM), while sprB cells were densely packed in immature biofilm with less matrix. The colony surface is critical for antibiotic resistance and cell survival. We have now developed the Grid Stamp-Peel method whereby the colony surface is attached to a TEM grid for negative-staining microscopy. The images showed that the top of the spreading convex WT colonies was covered by EPM with few interspersed cells. Cells exposed near the colony edge made head-to-tail and/or side-to-side contact and sometimes connected via thin filaments. Nonspreading sprB and gldG and gldK colonies had a more uniform upper surface covered by different EPMs including vesicles and filaments. The EPM of sprB, gldG, and WT colonies contained filaments ~2 nm and ~5 nm in diameter; gldK colonies did not include the latter. Every cell near the edge of WT colonies had one or two dark spots, while cells inside WT colonies and cells in SprB-, GldG-, or GldK-deficient colonies did not. Together, our results suggest that the colony surface structure depends on the capability to expand biofilm.

Three-Repeat Tau with Grain-Like Structures and Distribution in an 83-Year-Old Man.

We encountered an 83-year-old man with 3-repeat dominant grain-like tau deposition. Tau-positive lesions exhibited apparent similarity to argyrophilic grains in terms of their distribution in the ambient gyrus, amygdala, and dorsomedial temporal tip and the characteristic comma-like morphology. The abundant oligodendroglial tau immunoreactivities were 3-repeat dominant. Tuft-shaped astrocytes showed partial 3-repeat tau immnoreactivities. These grain-like structures, as well as tuft-shaped astrocytes and oligodendroglia, exhibited predominant 3-repeat tau immunoreactivity, suggesting that grain-like structures and their characteristic distribution are mutually linked and not unique to 4-repeat tau deposition. pTDP immunoreactivity, extensive macrophage infiltration, and spongiosis were associated with these 3-repeat tau deposits.

Speech disturbances due to left precentral cortical lesions.

We encountered two patients with lesions predominantly localized to the left precentral cortex who presented with speech disorders. Patient 1 had a lesion localized to the anterior part of the left precentral cortex along the precentral sulcus, in the middle part of the convexity. Patient 1 predominantly exhibited disturbance of prosody. Patient 2 had a lesion localized to the left precentral cortex, located slightly more posterior and more inferior in the convexity. Patient 2 predominantly exhibited disturbance of articulation, with distortion of sounds without apparent inconsistency. Even lesions localized to the left precentral cortex present with various types of speech disturbance.

An 85-year old male with levodopa-responsive parkinsonism followed by dementia and supranuclear ophthalmoplegia caused by alzheimer-type pathology without Lewy bodies.

An 85-year-old man developed l-dopa responsive parkinsonism indistinguishable from Parkinson's disease and subsequent dementia, followed by supranuclear ophthalmoplegia and neck dorsiflexion at the terminal stage. Midbrain tegmentum and medial temporal lobe were atrophic on magnetic resonance imaging, while decreased blood flow was predominant in frontotemporal lobes, detected by 3D-SSP of 123I- IMP SPECT. Alzheimer-type pathology without Lewy body pathology was confirmed at autopsy. Substantia nigra showed mild degeneration and several neurofibrillary tangles without Lewy body pathology or progressive supranuclear palsy cytopathology. L-dopa responsive parkinsonism could be an initial manifestation of Alzheimer's disease, which should be included in the differential diagnosis.

Limbic and nigral Lewy bodies and Alzheimer's disease pathology mimicking progressive supranuclear palsy in a 75-year-old man with preserved cardiac uptake of MIBG.

A 75-year-old man developed l-dopa non-responsive parkinsonism, supranuclear ophthalmoplegia, neck dorsiflexion, and dementia. Atrophy of the midbrain tegmentum on MRI and normal myocardial uptake of MIBG led to the clinical diagnosis of progressive supranuclear palsy (PSP). Autopsy revealed depigmentation of the substantia nigra and locus ceruleus. Alzheimer's disease pathology was advanced with PSP-like neurofibrillary tangles distribution, and Lewy bodies were abundant in limbic lobe, while scarce in lower brainstem nuclei. Tuft-shaped astrocytes were not apparent. Although decreased myocardial uptake of MIBG is a rule in patients harboring Lewy bodies, its normal uptake may be related to their absence in lower brainstem nuclei.

Dentatorubropallidoluysian atrophy without involuntary movement or dementia--a case report.

Recently, discussions about the clinical features of dentatorubropallidoluysian atrophy (DRPLA), especially the existence of an ataxo-choreoathetoid type, have increased. Traditionally, DRPLA patients have been thought to present with involuntary movements and dementia. Here, we report a patient that presented with ataxia, spasticity of the right lower extremity and mild sensory disturbances. He did not show either apparent involuntary movement or dementia. Mini-mental state examination demonstrated a score of 29/30. The cerebellar output system involving the dentate nuclei and superior cerebellar peduncles seemed to be atrophic yet the cerebellar input system involving the middle cerebellar peduncles was preserved on MRI. In addition, there was an expansion of the atrophin1 (ATN1) CAG repeat of chromosome 12p: 9/61. This seems to be the first case report of a genetically confirmed DRPLA patient presenting with clinical manifestations of Machado-Joseph disease (MJD/SCA3).

[Intermediate medullary infarction: a case report].

A 68-year-old man presented with right eye pain and vertigo. Thereafter, he gradually leaned rightward, then laid down. He felt nausea and vomited. His right upper eyelid drooped and he felt dysethesia of the right hand. On neurological examination, ptosis of his right eye with slightly miotic right pupil, paresis of the right soft palate and hoarseness were noted. Arm deviation test demonstrated rightward deviation. He presented sensory ataxia of the right upper and lower extremities: finger nose test showed mild dysmetria of the right upper extremity, heel knee test demonstrated dysmetria of right lower extremity and these findings worsened when he closed his eyes. He showed mild bending of his bilateral ring and little fingers when he did rapid alternative movement. He leaned rightward when he sat and closed his eyes. Position sense of his right upper and lower extremities was decreased and sometimes he could not answer correctly when asked on which direction his finger pointed. Pinprick sensation was mildly decreased on the left side not including the face. Touch and vibration sense were normal. SEP findings on upper and lower extremity stimulation were normal. MRI of the brain showed T2 high intensity and partially T1 low intensity lesion at the right medulla (Figure). MR angiography showed no apparent lesion of major arteries such as dissection of the vertebral arteries. He complained and presented with hiccup initially. On MRI, the lesion was thought to involve the spinothalamic tract, medial lemniscus and inferior olivary nucleus. Ambiguus nucleus was in the lesion and solitary nucleus near the lesion. There is no report that seems to describe clinical features of a lesion like that in this case. Intermediate medullary infarction may present dissociated sensory disturbance like Brown-Sequard syndrome and position sensory disturbance without disturbance of vibration sense.

[Molecular pathomechanism of distal myopathy with rimmed vacuoles].

Distal myopathy with rimmed vacuoles (DMRV) and hereditary inclusion body myopathy (HIBM) are genetically identical autosomal recessive muscle disorders caused by mutations in the GNE gene. This gene encodes a bifunctional protein with UDP-GlcNAc 2-epimerase and ManNAc kinase activities that catalyze the rate limiting step and the succeeding step, respectively, in the sialic acid biosynthetic pathway. V572L mutation is the most prevalent among Japanese DMRV patients and accounts for about 60% of mutant alleles. Clinical spectrum of DMRV/HIBM seems to be wider than previously thought in terms of both the severity of the disease and the range of affected organs. There are rare asymptomatic homozygotes with missense GNE mutations, indicating the presence of mitigating factors. Surprisingly, more than 10% of the patients had a variety of cardiac abnormalities, suggesting that skeletal muscle may not be the only organ involved. Studies on recombinant GNE demonstrate a loss-of-function nature of the missense mutations identified. Patients' cells show decreased sialylation status which can be recovered by adding GNE metabolites, such as ManNAc and NeuAc. This indicates the possibility of developing a therapy for DMRV/HIBM by giving these metabolites to patients although we have to await the model mice that are currently being produced at several laboratories.

Acute human T-lymphotropic virus type 1-associated myelopathy: a clinicopathologic study.

BACKGROUND: Recently, acute human T-lymphotropic virus type 1-associated myelopathy (HAM) was reported clinically without pathologic information. We report an autopsy case of acute HAM. OBJECTIVE: To report the case of a 52-year-old man with acute-onset gait disturbance followed by rapidly progressive paraplegia, who died 9 months later. RESULTS: The postmortem study showed swelling of the thoracic spinal cord. Histologically, there was inflammation and vacuolation in the white matter. CONCLUSION: We propose that these pathologic findings, mimicking tropical spastic paraparesis, may represent the characteristic pathologic features of acute HAM.