Comparison of Genomic and Epigenomic Expression in Monozygotic Twins Discordant for Rett Syndrome.

Monozygotic (identical) twins have been widely used in genetic studies to determine the relative contributions of heredity and the environment in human diseases. Discordance in disease manifestation between affected monozygotic twins has been attributed to either environmental factors or different patterns of X chromosome inactivation (XCI). However, recent studies have identified genetic and epigenetic differences between monozygotic twins, thereby challenging the accepted experimental model for distinguishing the effects of nature and nurture. Here, we report the genomic and epigenomic sequences in skin fibroblasts of a discordant monozygotic twin pair with Rett syndrome, an X-linked neurodevelopmental disorder characterized by autistic features, epileptic seizures, gait ataxia and stereotypical hand movements. The twins shared the same de novo mutation in exon 4 of the MECP2 gene (G269AfsX288), which was paternal in origin and occurred during spermatogenesis. The XCI patterns in the twins did not differ in lymphocytes, skin fibroblasts, and hair cells (which originate from ectoderm as does neuronal tissue). No reproducible differences were detected between the twins in single nucleotide polymorphisms (SNPs), insertion-deletion polymorphisms (indels), or copy number variations. Differences in DNA methylation between the twins were detected in fibroblasts in the upstream regions of genes involved in brain function and skeletal tissues such as Mohawk Homeobox (MKX), Brain-type Creatine Kinase (CKB), and FYN Tyrosine Kinase Protooncogene (FYN). The level of methylation in these upstream regions was inversely correlated with the level of gene expression. Thus, differences in DNA methylation patterns likely underlie the discordance in Rett phenotypes between the twins.

Blood-brain barrier destruction determines Fisher/Bickerstaff clinical phenotypes: an in vitro study.

OBJECTIVE: To ascertain the hypothesis that the phenotypic differences between Bickerstaff's brainstem encephalitis (BBE) and Miller Fisher syndrome (MFS) are derived from the differences in the effects of sera on blood-brain barrier (BBB) and blood-nerve barrier. BACKGROUND: Antibodies against GQ1b are frequently detected in BBE and MFS, and these two disorders may share the same pathogenesis, but the clinical phenotypes of BBE and MFS are substantially different. METHODS: The effects of sera obtained from BBE patients, MFS patients and control subjects were evaluated with regard to the expression of tight junction proteins and transendothelial electrical resistance in human brain microvascular endothelial cells (BMECs) and human peripheral nerve microvascular endothelial cells. RESULTS: The sera obtained from BBE patients decreased the transendothelial electrical resistance values and claudin-5 protein expression in BMECs, although the sera obtained from MFS patients had no effect on BMECs or peripheral nerve microvascular endothelial cells. This effect was reversed after the application of matrix metalloproteinase (MMP) inhibitor, GM6001. The presence or absence of anti-GQ1b antibodies did not significantly influence the results. MMP-9 secreted by BMECs was significantly increased after exposure to the sera obtained from BBE patients, whereas it was not changed after exposure to the sera obtained from MFS patients. CONCLUSIONS: Only the sera obtained from BBE patients destroyed BBB and it might explain the phenotypical differences between BBE and MFS. BBE sera disrupted BBB, possibly via the autocrine secretion of MMP-9 from BBB-composing endothelial cells.

Refractory acute disseminated encephalomyelitis with anti-galactocerebroside antibody.

Acute disseminated encephalomyelitis causes multifocal demyelination in the central nerve system. Although this disease generally responds well to steroid therapy, it is occasionally steroid-resistant, leading to poor outcomes. Serological markers of prognosis are currently unavailable. We measured anti-glycolipid antibodies in 25 consecutive patients with acute disseminated encephalomyelitis, and found that four patients were positive for anti-galactocerebroside antibodies. All four patients had a poor response to steroids. We summarize clinical information on these four patients and three similar patients reported previously. This is the first report to describe concomitant involvement of the central nerve system and peripheral nervous system in anti-galactocerebroside antibody-associated acute disseminated encephalomyelitis, consistent with the location of galactocerebroside, and to document a dramatic response to repeated intravenous immunoglobulin therapy after unsuccessful steroid treatment in one patient.

Intravenous immunoglobulin (IVIg) with methylprednisolone pulse therapy for motor impairment of neuralgic amyotrophy: clinical observations in 10 cases.

BACKGROUND: Neuralgic amyotrophy (NA) is a distinct peripheral nervous system disorder characterized by attacks of acute neuropathic pain and rapid multifocal weakness and atrophy unilaterally in the upper limb. The current hypothesis is that the episodes are caused by an immune-mediated response to the brachial plexus, however, therapeutic strategies for NA have not been well established. METHODS AND RESULTS: We retrospectively reviewed 15 case series of NA; 10 of the 15 patients received intravenous immunoglobulin (IVIg) with methylprednisolone pulse therapy (MPPT) and 9 of these 0 patients showed clinical improvement of motor impairment. CONCLUSION: Our clinical observations do not contradict the possibility that IVIg with MPPT may be one of the potential therapeutics for NA, however the efficacy remains to be established. Further confirmatory trials are needed in patients with various clinical severities and phases of NA. Further basic research and confirmatory trials should be performed to survey the efficacy of such immunomodulation therapy for NA.

[Rapid improvement by rituximab treatment in a case of demyelinating polyneuropathy with anti-myelin-associated glycoprotein antibody].

Polyneuropathy associated with antibodies directed against myelin-associated glycoprotein (MAG) is a chronic symmetric sensorimotor demyelinating neuropathy caused by monoclonal IgM against MAG (anti-MAG neuropathy). Intravenous immunoglobulin therapy (IVIg) has been partially successful in patients with anti-MAG neuropathy. A placebo-controlled trial of rituximab in patients with anti-MAG neuropathy has been reported. We report rapid improvement in a patient with anti-MAG neuropathy using rituximab. A 58-year-old man presented with abnormal sensation, weakness of the limbs, and unsteadiness. He was previously diagnosed with chronic inflammatory demyelinating neuropathy and was treated with steroid pulse therapy and IVIg. However, these treatments were not effective. On examination at our hospital, he showed areflexia in all limbs, mild weakness in distal portions of upper and lower extremities, sensory ataxia, and hypesthesia/hypalgesia except for his face. He showed high serum IgM levels (323mg/dl). He did not show M protein on immunoelectrophoresis; however, anti-MAG and anti-sulfoglucuronyl paragloboside (SGPG) antibodies were detected by immunoblot and enzyme-linked immunosorbent assay, respectively. He was diagnosed with anti MAG neuropathy and was administered four cycles of intravenous rituximab at a dose of 375mg/m(2)/week. After the first cycle of rituximab administration, he showed improvement in two-point discrimination of middle fingers (10/13 before therapy to 7/7mm after administration). Two-point discrimination and vibration markedly improved after four cycles of rituximab administration. Romberg sign became negative after 7 months. Anti-SGPG antibody titers reduced from 0.554 before rituximab administration to 0.307 (OD) at 1,600 dilution, 4 months after administration. We concluded that rituximab was effective for the treatment of anti-MAG neuropathy. We suggested that rapid and long-term improvement in our patient might be caused not only by preventing the formation of new antibody-secreting cells and antibody-titer reduction but also affecting the balance of proinflammatory cytokines and regulatory cytokines production.

Antibodies to LM1 and LM1-containing ganglioside complexes in Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy.

LM1 is localized in human peripheral nerve myelin. Antibodies to ganglioside complexes (GSCs) have been reported in Guillain-Barré syndrome (GBS). We investigated IgG antibodies to LM1 and two GSCs (GM1 and LMI, or GD1b and LM1) in the sera of each 40 patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and GBS, using ELISA. We detected anti-LM1 antibody in five with GBS and seven with CIDP; anti-GM1/LM1 antibody in three with GBS and one with CIDP; and anti-GD1b/LM1 antibody in two with CIDP. Antibodies to LM1 and LM1-containing GSCs may be among the targets for autoimmunity in GBS and CIDP.

Pancreatic cancer screening employing noncontrast magnetic resonance imaging combined with ultrasonography.

PURPOSE: We have conducted an initial evaluation on the potential of combining noncontrast magnetic resonance imaging (MRI) and ultrasonography (US) to screen for pancreatic cancer. MATERIALS AND METHODS: An independent ethics committee approved this study. A total of 2511 patients who underwent US were enrolled. Among them, noncontrast MRI was performed in patients in whom the entire pancreas was difficult to depict or in those with US-suspected pancreatic lesions. In total, using 1.5-T MRI, T1- and T2-weighted imaging, magnetic resonance cholangiopancreatography, and diffusion-weighted imaging, we acquired a variety of images. The efficacy of US and MRI in screening for pancreatic lesions, including pancreatic cancer, was evaluated. RESULTS: Of 2511 patients, 184 underwent MRI, and the pancreas was demonstrated in all of them. Among the 2511, five pancreatic cancers were detected by MRI combined with US (detection rate 0.20%). Of the five pancreatic cancers, three were detected by US (detection rate 0.12%) and two by MRI. Four of the five pancreatic cancers were resectable. CONCLUSION: By combining noncontrast MRI with US, pancreatic cancer can be detected with high accuracy. Other pancreatic lesions that require follow-up, including intraductal papillary mucinous neoplasms, can also be detected. Thus, pancreatic cancer screening with a combination of US and MRI is suggested.

Diagnosis of breast cancer with multidetector computed tomography: analysis of optimal delay time after contrast media injection.

PURPOSE: The aim of this study was to investigate the optimal delay time after a contrast media injection for multidetector computed tomography (MD-CT) images in the diagnosis of breast cancer patients. MATERIALS AND METHODS: Thirty-one patients who underwent MD-CT for their preoperative examination and who had postoperatively confirmed pathology were enrolled. Four-phase images of dynamic contrast enhanced study were acquired using four-detector MDCT. All cases were mammographically classified into two groups according to BI-RADS: nondense and dense groups. The CT value of the background mammary gland, background breast enhancement (BBE), and tumor-background mammary gland contrast (TBC) were compared between the two groups. RESULTS: The CT value of the dense group was significantly higher than that of the nondense group in all phases. BBE in both nondense and dense groups showed no significant differences in any of the phases. In the nondense group, TBC was significantly higher in both the second and the third phases than in the first phase, while in the dense group, TBC was significantly higher in the second phase than in the first and third phases. CONCLUSION: The optimal delay time to depict breast cancer is 80 s after a contrast media injection, regardless of the density level of the background mammary gland.

Retention time of attenuated response to diacetyl after pre-exposure to diacetyl in Caenorhabditis elegans.

The retention time of attenuated chemotactic response to continuous presentation of odorant diacetyl was investigated in the nematode Caenorhabditis elegans. The level of chemotactic response of nematodes pre-exposed to diacetyl for 90 min was significantly smaller than that of nonexposed control nematodes. In this study, wild-type (N2) nematodes were maintained at 15, 20 and 25 degrees C after pre-exposure to diacetyl. At 20 degrees C, there was a decrease in response to diacetyl continuing for up to 6 hr after pre-exposure to the chemical, but not up to 12 hr. Interestingly, the decrease in response to diacetyl did not continue up to 2 hr in nematodes bred at 15 degrees C, although it continued beyond 12 hr in nematodes bred at 25 degrees C. These results indicate that the retention time of attenuated chemotactic response to diacetyl is dependent on the environmental breeding temperature of nematodes. The breeding temperature correlated with aging speed of nematodes, suggesting that a short life span (higher aging speed) prolongs the retention time of attenuated chemotactic response to diacetyl after pre-exposure to diacetyl. In the long-lived daf-2, age-1, clk-1 and isp-1 mutants, the effect of diacetyl did not continue up to 2 hr. The short-lived daf-16, daf-18, mev-1 and gas-1 mutants showed a longer duration of decrease in response to diacetyl, that is, the retention time of attenuated chemotactic response to diacetyl continued beyond 12 hr. There is a possibility that the duration of decrease in response to diacetyl after pre-exposure to diacetyl was inversely related to the length of nematodes' life span.

Drainage of the tracheal blind pouch created by laryngotracheal separation.

Laryngotracheal separation is a simple and reliable operation for the treatment of patients with repetitive and intractable aspiration; however, it is apprehended that pooling in the tracheal blind pouch may cause postoperative complications. In the present study, we examined drainage of the blind pouch created by laryngotracheal separation. Fourteen patients aged 3-63 years with repetitive aspiration pneumonia underwent laryngotracheal separation by the modified Lindeman procedure. A barium swallow was performed 10-30 days after surgery. X-rays of the lateral view of the neck were taken at 6 and 24 h after the swallow, and then every 24 h until the contrast medium cleared. The contrast medium in the blind pouch cleared within 24 h in nine patients. In the remaining five, the clearance time was < or =48 and < or =72 h in two patients each, and 96 h in one patient. The clearance time in patients aged under 20 years was < or =24 h, while middle-aged to elderly patients showed prolonged clearance time. No late complications of the blind pouch, such as infections, were observed. The potential risk of complications caused by pooling in the tracheal blind pouch in laryngotracheal separation is prevented presumably due to the slow but continuous turnover of pooling material. This result supports the validity and usefulness of laryngotracheal separation for the treatment of intractable aspiration.

Oral immunogenicity and protective efficacy in mice of transgenic rice plants producing a vaccine candidate antigen (As16) of Ascaris suum fused with cholera toxin B subunit.

Cereal crops such as maize and rice are considered attractive for vaccine production and oral delivery. Here, we evaluated the rice Oryza sativa for production of As16-an antigen protective against the roundworm Ascaris suum. The antigen was produced as a chimeric protein fused with cholera toxin B subunit (CTB), and its expression level in the endosperm reached 50 microg/g seed. Feeding the transgenic (Tg) rice seeds to mice elicited an As16-specific serum antibody response when administered in combination with cholera toxin (CT) as the mucosal adjuvant. Although omitting the adjuvant from the vaccine formulation resulted in failure to develop the specific immune response, subcutaneous booster immunization with bacterially expressed As16 induced the antibody response, indicating priming capability of the Tg rice. Tg rice/CT-fed mice orally administered A. suum eggs had a lower lung worm burden than control mice. This suggests that the rice-delivered antigen functions as a prophylactic edible vaccine for controlling parasitic infection in animals.

Detecting breast cancer with non-contrast MR imaging: combining diffusion-weighted and STIR imaging.

We combined diffusion-weighted (DWI) and short TI inversion recovery (STIR) imaging to evaluate the diagnostic capability of non-contrast magnetic resonance (MR) imaging to detect breast cancer. Seventy women patients underwent mammography and MR imaging with combined DWI (b factor: 1000) and STIR that revealed malignancy, and postoperative pathological examination confirmed breast cancer. Interpreted images were evaluated for sensitivity, false negative rate (FN), sensitivity by pT, and sensitivity by background density of the mammary gland. Of the 70 cases, 68 were diagnosed as cancer by DWI and STIR (sensitivity, 97% [68/70]; FN, 2.9% [2/70]). Sensitivities by pT were: pTis, 67% (4/6); pT1, 100% (33/33); and pT2-4, 100% (31/31). No significant differences were observed in sensitivity between pT1 and pT2-4 (P<0.001). Sensitivities by background density of mammary gland were: fatty/scattered fibroglandular tissue, 95% (20/21) and heterogeneous fibroglandular tissue/mostly fibroglandular tissue, 98% (48/49). No significant differences were observed (P<0.001). Two cases, an intraductal and an apocrine carcinoma, were incorrectly diagnosed by MR imaging. Precise diagnosis of breast cancer is possible with combined DWI and STIR, even in non-contrast MR imaging, regardless of the diameter or background density of mammary gland. It is hoped that non-contrast MR imaging that combines DWI and STIR will become an established clinical screening method.

[New method for accurate ECG trigger of intraaortic balloon counterpulsation during off-pump coronary artery bypass surgery].

BACKGROUND: Retractions of the heart required for exposure and construction of distal anastomoses often decrease R-wave amplitude of ECG and interfere with intraaortic balloon pump (IABP) trigger during off-pump coronary artery bypass (OPCAB). Missing R wave trigger results in asynchronous work of IABP and probably produces hemodynamic instability. We report our early experience with a new interface BPI 202 (Osypka Medical, Inc., USA) for sensing accurate ECG trigger for IABP during OPCAB procedure. CASES: Six high-risk patients undergoing multivessel OPCAB using BPI 202 are described. RESULTS: With the new interface BPI 202, simulated R wave signal could be processed from an external dual chamber pacemaker sensing surface R wave. The simulated R wave was successfully used for controlling IABP and secured a synchronous work between the heart and IABP during heart retraction maneuver. BPI 202, an interface for IABP appeared to facilitate the intraoperative management of our series of patients. CONCLUSIONS: We believe BPI 202 can produce a synchronous work of IABP during OPCAB procedures to high-risk patients and avoid dangerous hemodynamic instability.

[Developmental changes of N400 event related potential of a semantic category decision task and modality specific findings in patients with developmental dyslexia].

We investigated modality-specific changes in N400 event related potential using a semantic category decision task in 38 control subjects and 8 patients with developmental dyslexia. In control children under 10 years old, auditory N400 showed a negative deflection over the fronto-centro-parietal areas with substantial amplitude. Control children over 10 years old showed a similar pattern of N400 waves in a visual and an auditory-visual modality, suggesting that the visual modality becomes dominant in the late teens. Dyslexic children showed more errors on a visual than auditory modality task with poorer N400 waves for visual stimuli. However, peak latencies of N400 in an auditory-visual modality were almost the same for auditory stimuli in control children. Differences in the N400 pattern in children might reflect the fragility and reversibility of the semantic processes through stimulus modalities.

Characteristic findings of auditory brainstem response and otoacoustic emission in the Bronx waltzer mouse.

Auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs) were evaluated serially from 1 to 22 months in Bronx waltzer homozygotes (bv/bv), heterozygotes (+/bv) and control (+/+) mice, which were differentiated by means of PCR of marker DNA (D5Mit209). The wave IV threshold of the click-evoked ABR was higher than the DPOAE threshold with the DP growth method in each bv/bv, although the two thresholds were almost the same in the +/+ group. The DP value at 2f(1) - f(2) in the bv/bv showed an apparent decrease at 2 to 3 months of age with 80 dB SPL stimulation using f(2) frequency 7996 Hz and frequency ratio f(2)/f(1) = 1.22, compared to control or heterozygote mice. It was characteristic that the 2f(2) - f(1) DP signal-to-noise ratio (SNR) value was more preserved from 80 to 60 dB SPL than the 2f(1) - f(2) DP value at f(2) frequency 7996 Hz in most bv/bv, however, control mice showed almost the same levels of 2f(1) - f(2) and 2f(2) - f(1) SNR value at both f(2) frequencies of 6006 and 7996 Hz. The preservation of a substantial 2f(2) - f(1) DP suggested that it would be generated basal to the primary-tone place on the basilar membrane and there might be a reflection of the unique function of the remaining outer hair cells in the Bronx waltzer mice. These findings suggest that combination of ABR with DPOAE could offer useful information about differentiating the mechanism of hair cell dysfunction of the hereditary hearing impairment in the clinical fields.