Organization of Vascular Cells in the Haustorium of the Parasitic Flowering Plant Cuscuta japonica

The stem parasite dodder, Cuscuta japonica, has evolved a specialized root-like organ, the haustorium, which is differentiated from the stem. In order to take up water and nutrients, C. japonica reprograms haustorial cells to vascular cells, connecting the host's vascular system to its own. However, little is known about vascular differentiation in haustoria. In this study, we first confirmed the temporal and spatial expression profiles of vascular cell type-specific genes, CjAPL, CjSEOR1, CjWOX4 and CjTED7, to examine whether phloem companion cells, developing sieve elements, procambial cells and differentiating xylem cells, respectively, are present in the haustoria. CjAPL and CjSEOR1 decreased, and CjWOX4 showed a transient increase before the onset of xylem vessel formation, and then decreased. CjTED7 increased coincidentally with xylem vessel formation. In situ hybridization demonstrated that CjWOX4-expressing cells and phloem-conducting cells are in close proximity, and occupied a domain distinguishable from xylem vessels, suggesting differentiation of a phloem/procambial domain and a xylem domain in the haustorium. Secondly, expression of regulatory genes that are involved in determination of the fate of procambial cells was investigated. Expression patterns of CjCLE41, CjGSK3 and CjBES1suggested that TDIF-TDR-GSK3-mediated signaling is activated in haustoria. The natural antisense transcript of CjCLE41 was detected in haustoria, implying the sense regulation of CjCLE41. Expression profiles of the regulatory genes, combined with those of cell type-specific marker genes, suggest that reprogramming of haustorial cells to vascular cells is regulated in a way that allows the immediate formation of xylem vessels by alleviating inhibition of xylem differentiation.

Arabinogalactan Proteins Accumulate in the Cell Walls of Searching Hyphae of the Stem Parasitic Plants, Cuscuta campestris and Cuscuta japonica

Stem parasitic plants (Cuscuta spp.) develop a specialized organ called a haustorium to penetrate their hosts' stem tissues. To reach the vascular tissues of the host plant, the haustorium needs to overcome the physical barrier of the cell wall, and the parasite-host interaction via the cell wall is a critical process. However, the cell wall components responsible for the establishment of parasitic connections have not yet been identified. In this study, we investigated the spatial distribution patterns of cell wall components at a parasitic interface using parasite-host complexes of Cuscuta campestris-Arabidopsis thaliana and Cuscuta japonica-Glycine max. We focused on arabinogalactan proteins (AGPs), because AGPs accumulate in the cell walls of searching hyphae of both C. campestris and C. japonica. We found more AGPs in elongated haustoria than in pre haustoria, indicating that AGP accumulation is developmentally regulated. Using in situ hybridization, we identified five genes in C. campestris that encode hyphal-expressed AGPs that belong to the fasciclin-like AGP (FLA) family, which were named CcFLA genes. Three of the five CcFLA genes were expressed in the holdfast, which develops on the Cuscuta stem epidermis at the attachment site for the host's stem epidermis. Our results suggest that AGPs are involved in hyphal elongation and adhesion to host cells, and in the adhesion between the epidermal tissues of Cuscuta and its host.

Cognition and event-related potentials in adult-onset non-demented myotonic dystrophy type 1

OBJECTIVE

To clarify the cognitive and event-related potentials (ERPs) profiles of adult-onset genetically-proven non-demented myotonic dystrophy type 1 (DM1).

METHODS

Fourteen DM1 patients and matched 14 normal controls were enrolled. DM1 patients were compared with normal controls, using a variety of neuropsychological tests; an auditory "oddball" counting paradigm for the ERPs, and low-resolution brain electromagnetic tomography (LORETA). For patients, ERPs and neuropsychological parameters were correlated with CTG repeat size, duration of illness, grip strength, and arterial blood gas analysis.

RESULTS

Frontal lobe dysfunction, prolonged N1 latency, and attenuated N2/P3 amplitudes were observed in DM1. Longer CTG repeat size was associated with fewer categories achieved on Wisconsin Card Sorting Test. Greater grip strength was associated with better scores on color-word "interference" of Stroop test. P3 latency was negatively correlated with PaO(2). LORETA revealed significant hypoactivities at the orbitofrontal and medial temporal lobe, cingulate, and insula. There was no correlation between ERPs and CTG expansion.

CONCLUSIONS

Adult-onset non-demented DM1 presented frontal lobe dysfunction. Absence of correlations between CTG repeat size and objective ERP parameters suggested CTG expansion in lymphocytes does not directly contribute to cognitive dysfunction.

SIGNIFICANCE

CTG expansion in lymphocytes does not directly contribute to cognitive dysfunction of adult-onset non-demented DM1.

Nucleation and growth of hydroxyapatite on an amino organosilane overlayer

An amino organosilane overlayer (NH(2)-overlayer) was successfully processed on Si/SiO(2) substrates. Remarkable nucleation and growth of hydroxyapatite were found to take place on an NH(2)-overlayer after Si/SiO(2) substrates covered with the NH(2)-overlayer were soaked in supersaturated solutions with respect to Ca(2+) and PO(4)(3-) ions [1.0SBF (simulated body fluid), which contains similar compositions to that in a living body and 1.5SBF in which only Ca(2+) and PO(4)(3-) concentrations are 1.5 times than that in 1.0SBF]. The experimental results demonstrated that HAp nucleation on an NH(2)-overlayer is related to the electrostatic attractive force between positive NH(2)-overlayer surface and negative incipient HAp microparticles homogeneously nucleated in 1.5SBF solution at 50 degrees C. On the contrary, fewer HAp particles were observed on negatively charged "OH" terminated self-assembled monolayer (SAM) because of the repulsive interaction. The Ca/P molar ratios of HAp particles increased from 0.92 at the beginning of nucleation in 1.5SBF to 1.63 in 14 days after growth in 1.0SBF at 37 degrees C. After 14 days of soaking in 1.0SBF, a dense HAp film with the thickness up to 8.6 microm was formed on the NH(2)-overlayer.

Induction of MMP-9 in normal human bronchial epithelial cells by TNF-alpha via NF-kappa B-mediated pathway

In this study, we determined whether the proinflammatory cytokines tumor necrosis factor (TNF)-alpha and interleukin-1 beta contribute to the regulation of matrix metalloproteinase (MMP)-9 in human bronchial epithelial cells and whether the induction of MMP-9 is regulated by the transcription factor nuclear factor (NF)-kappa B. We demonstrated that TNF-alpha induced MMP-9 at both the protein and mRNA levels in human bronchial epithelial cells and that interleukin-1 beta did not. In contrast, induction of the tissue inhibitor of metalloproteinase-1 by TNF-alpha was less than that of interleukin-1 beta. Increased expression of MMP-9 and NF-kappa B activation induced by TNF-alpha were inhibited by pyrrolidine dithiocarbamate and N-acetyl-L-cysteine but were not inhibited by curcumin. These results suggest that TNF-alpha induces the expression of MMP-9 in human bronchial epithelial cells and that this induction is mediated via the NF-kappa B-mediated pathway.

Aligned bioactive mesoporous silica coatings for implants

Ongoing research is reported aimed at preparing mesoporous silica coatings on various substrates for medical applications by a biomimetic approach (self-assembling of organic/inorganic sol-gel systems into ordered structures). Tetraethylorthosilicate (TEOS) was selected as the silica precursor, and amphiphilic triblock copolymers poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide), and the cationic surfactant cetyltrimethyl ammonium chloride (CTAC), as structure-directing agents. The mesochannels diameter could be adjusted by changing the directing agent, and a preferred alignment of the mesostructure was observed independently of the used substrate (glass, silicon, Ti or Ti6Al4V). Three different treatments (thermocalcination, photocalcination, and solvent extraction) have been also studied to remove the organic templates, of which photocalcination showed to be the most versatile. When soaked in a simulated body fluid, mesoporous silica coatings induced apatite formation after seven days.

Molecular cloning and characterization of a thioredoxin/nucleoside diphosphate kinase related dynein intermediate chain from the ascidian, Ciona intestinalis

Flagellar outer arm dynein from the ascidian, Ciona intestinalis, contains five intermediate chains (IC1-5). Molecular cloning of C. intestinalis IC3 shows significant sequence homology to the dynein intermediate chain (IC1) from sea urchin and human NM23-H8 protein. The N-terminal thioredoxin-related region is well conserved in the C. intestinalis IC3, sea urchin IC1, and human NM23-H8 protein. Three NDP kinase (NDPK)-related sequences are present in middle portions of both C. intestinalis IC3 and sea urchin IC1, but the human NM23-H8 protein had only two. A large part of the C-terminal glutamic acid-rich region present in sea urchin IC1 was greatly reduced in C. intestinalis IC3 and completely lost in human NM23-H8. Thus, thioredoxin/NDPK-related dynein intermediate chains (TNDK-DIC) would be a characteristic of metazoan flagella and they have become smaller in size and less acidic during evolution.

[A case of slowly progressive "pharyngeal-cervical-brachial variant of Guillain-Barré syndrome (PCB)"]

A 69-year-old woman was admitted to our hospital because of slowly progressive weakness in the neck, shoulders, proximal arms, oropharyngeal muscles. From a viewpoint of clinical course and signs, it was suspected that the patient was suffered from motor neuron disease. However, serial electrophysiological studies showed the existence of local demyelination of the motor nerves. The immunoadsorption was then performed and marked recovery of symptoms was obtained. In this case, we could not detect any established anti-ganglioside antibodies which was related to pharyngeal-cervical-brachial variant of Guillain-Barré syndrome(PCB) or Guillain-Barré syndrome (GBS). It is suggested that unknown anti-ganglioside antibody may play an important role in cases of PCB. Despite of atypical slowliness of clinical progression and negative results of immunological studies, this patient is considered to be suffered from PCB, because of the results of electrophysiological studies and effectiveness of immunoadsorption therapy. Accordingly it may be important to take the possibility of PCB into diagnostic consideration, whenever the patient shows slowly progressive weakness in proximal arms, oropharyngeal muscles.

Abnormal information processing in dementia of Alzheimer type. A study using the event-related potential's field

Electrical field changes of event-related potentials (ERPs) were investigated in 26 patients with dementia of Alzheimer's type (DAT) and 12 age-matched normal subjects. The patients were assessed with the Clinical Dementia Rating and Mini-Mental State. Each patient selected had only mild to moderate mental disability. Auditory oddball stimulation was presented at 1.5 s intervals and 1,000 Hz for the nontarget and 2,000 Hz for the target tones, both at 85 dB. The target tones were 20% of all the tones. The reference-independent data (latency, global field power: GFP, dissimilarity index: DISS and location of centroids) were obtained and analyzed for each ERP component. The momentary electric strength or 'hilliness' of the ERPs landscape was indicated by GFP. The patients showed prolonged latencies and decreased P300 GFP amplitudes and of N100 GFP. These findings suggest that the abnormal electrical field of ERP may reflect abnormal information processing following the attentional process for target stimuli in DAT patients.

Bioactive glass-mesoporous silica coatings on Ti6Al4V through enameling and triblock-copolymer-templated sol-gel processing

The combination of thick glass coatings that can protect Ti6Al4V from corrosion in the body fluids, and mesoporous silica films able to readily induce the formation of apatite when immersed in a simulated body fluid (SBF), has been investigated in this work as a possible route towards more resistant and long-lasting implants. Glasses in the system Si-Ca-Mg-Na-K-P-O with thermal expansion coefficients close to that of Ti6Al4V were prepared and used to coat this alloy by an enameling technique. However, the glasses apt to coat Ti6Al4V exhibited a very limited capacity to induce apatite formation in SBF. In order to enhance their bioactivity, a thin film of mesoporous silica was applied on the exterior of the specimens by spin coating a sol-gel solution. When tested in SBF, these coatings induced apatite formation after 7 days. The mesoporosity of the silica film was created through a triblock-copolymer-templating process. The diameters of the mesochannels could be adjusted by changing the size of the directing agent. A preferred alignment of the mesostructure was observed. The removal of the organic templates could be achieved through a photocalcination treatment, which, compared to conventional thermocalcination, offered several advantages.

[Usefulness of diffusion-weighted MRI in the diagnosis of transient ischemic attacks]

Diffusion-weighted imaging(DWI) has been demonstrated to be valuable for assessment of ischemic stroke patients. The aim of this study is to evaluate clinical usefulness of DWI in the diagnosis of transient ischemic attack(TIA). Nineteen patients with symptoms of TIA were studied. DWI was taken with 1.5 Tesla MRI system using spin echo EPI sequence. Seven patients revealed areas of hyperintensity (brightness) on DWI and of hypointensity on apparent diffusion coefficient(ADC) maps relative to normal brain. As the duration of TIA symptom elongated, the percentage of patients with DWI abnormalities became higher. DWI enabled to detect areas of hyperintense lesion in all three patients as early as 3 hours after the onset, while conventional T2 weighted imaging showed in one. All the DWI abnormalities were irreversible in spite of the complete recovery from TIA. DWI is an useful technique for the detection of responsible lesions in TIA. However, TIA cannot be ruled out even if DWI does not demonstrate any abnormal signals.

Perseveration for novel stimuli in Parkinson's disease: an evaluation based on event-related potentials topography

Event-related potential topography produced by novel and target stimuli was used to detect dysfunction of mental switching (perseveration) in nondemented patients with Parkinson's disease. The study participants were 15 patients with Parkinson's disease and 13 age-matched healthy control patients. Ten percent of the novelty tones with pitches of 125 and 500 Hz were added to 20% of the target tones that had a pitch of 1000 Hz. Patients were instructed to count the target tones. The modified Wisconsin Card Sorting Test was used to evaluate frontal lobe function. Patients with Parkinson's disease showed a significant decrease in the achieved categories and an increase in perseverative errors in the Wisconsin Card Sorting Test. These results indicate that the cognitive impairment of patients with Parkinson's disease can be characterized as failure of mental switching related to frontal lobe dysfunction based on basal ganglia disturbance. As compared with the control patients, patients with Parkinson's disease had shorter P3 latencies to the novel stimuli and a more frontal distribution on the P3 map, especially for the 125-Hz stimuli. This characteristic of P3 to novel stimuli in the patients with Parkinson's disease, but not in the control patients, is categorized by P3a (novelty P3). Our findings suggest that decreased mental switching causes lack of novelty P3 habituation in patients with Parkinson's disease and that it is related to learning disabilities based on dysfunction of the frontal lobe and basal ganglia.

[Pulmonary adenocarcinoma with central ossification]

A 70-year-old woman was admitted in April 1997 because a coin lesion in the left middle lung field was observed on chest roentgenograms. The lesion had slightly increased in size since 1994, when it was first pointed out. Chest computed tomography elucidated a high density area with irregular borders in the center of the shadow in S 3 a. Transbronchial biopsy revealed adenocarcinoma, and a left upper lobectomy was performed. The resected specimen demonstrated a tumor with central ossification and pleural indentation. Histologic examination determined that the the tumor was a papillary adenocarcinoma with central ossification containing marrow tissue. Primary lung cancer with central ossification is very rare, and only 6 cases have been reported to date, including this case.

[Evaluation of cerebral metabolism by multi-voxel proton magnetic resonance spectroscopy imaging in chronic unilateral internal carotid artery occlusion]

Proton magnetic resonance spectroscopy(1H-MRS) has less been used to analyze cerebral metabolism in ischemic lesions compared to single photon emission computed tomography or positron emission computed tomography. Recent advances in magnetic resonance imaging apparatus and the related software have made possible obtaining multi-voxel 1H-MRS in a single study. We examined multi-voxel 1H-MRS in patients with unilateral internal carotid artery(ICA) occlusion to study the relationship between cerebral metabolism and cerebral blood flow. Fifteen patients(male 11; female 4, 47-76; average 67.1 year-old) with chronic unilateral ICA occlusion and without any marked infarction were studied. 1H-MRS was obtained using a 1.5 T Siemens Magnetom Vision scanner. Multi-voxel spectra were recorded using a SE-2 D-CSI sequence(TR/TE = 1500/135 ms). The volume of interest was 90 x 90 x 20 mm3, placed axially above the lateral ventricle. The single voxel size was 10 x 10 x 20 mm3. N-acetyl aspartate/creatine ratios(NAA/Cr) were calculated on each voxel and were averaged in view of the cortex and the white matter. The regional cerebral blood flow(CBF) was measured by Xenon-CT method. Eight patients were also examined by acetazolamide challenge to evaluate the cerebrovascular reserve capacity. NAA/Cr ratios in normal subjects were 1.905 +/- 0.090(mean +/- standard deviation) in the cortex and 2.183 +/- 0.258 in the white matter in 40's(n = 6), 2.046 +/- 0.166 in the cortex and 2.039 +/- 0.288 in the white matter in 60's(n = 5). The study revealed 7 patients with normal NAA/Cr ratio and CBF, 5 with reduced NAA/Cr ratio and normal CBF, and 3 with reduced NAA/Cr ratio and CBF in the affected cortex. A low correlation coefficient of 0.46 was noted between NAA/Cr ratio and the cerebrovascular reserve capacity calculated by acetazolamide challenge in the affected cortex. In the range of less than +10%(lower limit) in percentile change of regional CBF after acetazolamide injection, NAA/Cr ratio was distributed between 1.600 and 2.044, which were normal or slightly under the lower limit(mean-2 x standard deviation). Multi-voxel 1H-MRS is useful for the evaluation of cerebral metabolism, because it enables to quantify different chemicals in many fields at one time and to compare its distribution with regional CBF. In patients with unilateral ICA occlusion, NAA/Cr ratio of the affected cortex varies depending on the collateral circulation and the contralateral ICA lesions. The Extracranial-Intracranial Bypass should be considered if the case with unilateral ICA occlusion reveals reduced CBF and normal or slightly decreased NAA/Cr ratio in the affected cortex.

[A case of Dyke-Davidoff-Masson syndrome with total hemiatrophy]

We reported a 39-year-old man with Dyke-Davidoff-Masson syndrome presenting with total hemiatrophy. The patient had a muscle defect in the left occipital lesion at birth and left hemiatrophy including the face in his infancy. The present illness consists of atrophy of the left face, trunk and extremities, a muscle defect accompanied with scleroderma of the left dorsal cervical lesion, bilateral pes cavus, cleft palate, left hemiparesis, including facial palsy and diminished superficial sensation of the left side of the body. Decrease in right cranial volume and slight elevation of the right temporal pyramid and the superior border of the orbit were seen on the X-ray study of the head. Atrophy of the right cerebrum and cerebral peduncle was seen on magnetic resonance imaging. These findings suggest that hemiatrophy of the brain was responsible for total hemiatrophy of the body in this patient. The etiology of cerebral hemiatrophy is not known. There is only a report of Dyke-Davidoff-Masson syndrome accompanied with total hemiatrophy.