Efficacy of exon-skipping therapy for DMD cardiomyopathy with mutations in actin binding domain 1.

Exon-skipping therapy is a promising treatment strategy for Duchenne muscular dystrophy (DMD), which is caused by loss-of-function mutations in the DMD gene encoding dystrophin, leading to progressive cardiomyopathy. In-frame deletion of exons 3-9 (Δ3-9), manifesting a very mild clinical phenotype, is a potential targeted reading frame for exon-skipping by targeting actin-binding domain 1 (ABD1); however, the efficacy of this approach for DMD cardiomyopathy remains uncertain. In this study, we compared three isogenic human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) expressing Δ3-9, frameshifting Δ3-7, or intact DMD. RNA sequencing revealed a resemblance in the expression patterns of mechano-transduction-related genes between Δ3-9 and wild-type samples. Furthermore, we observed similar electrophysiological properties between Δ3-9 and wild-type hiPSC-CMs; Δ3-7 hiPSC-CMs showed electrophysiological alterations with accelerated CaMKII activation. Consistently, Δ3-9 hiPSC-CMs expressed substantial internally truncated dystrophin protein, resulting in maintaining F-actin binding and desmin retention. Antisense oligonucleotides targeting exon 8 efficiently induced skipping exons 8-9 to restore functional dystrophin and electrophysiological parameters in Δ3-7 hiPSC-CMs, bringing the cell characteristics closer to those of Δ3-9 hiPSC-CMs. Collectively, exon-skipping targeting ABD1 to convert the reading frame to Δ3-9 may become a promising therapy for DMD cardiomyopathy.

Focal ictal direct current shifts by a time constant of 2 seconds were clinically useful for resective epilepsy surgery.

OBJECTIVE: Ictal direct current shifts (icDCs) and ictal high-frequency oscillations (icHFOs) have been reported as surrogate markers for better surgical outcomes in epilepsy surgery. icDCs have been classified into two types: rapid and slow development. icDCs have been investigated with a time constant of 10 s (TC10s); however, many institutes use electroencephalography with a time constant of 2 s (TC2s). This study aimed to evaluate whether icDCs can be observed adequately with TC2s; moreover, it examined the relationship between the resected core area of icDCs or icHFOs and surgical outcomes, occurrence rate of each type of icDCs, and relationship between each type of icDCs and pathology. METHODS: Twenty-five patients with intractable focal epilepsy were analyzed retrospectively. icDCs and icHFOs were defined according to common metrics. The amplitude of icDCs was defined at >200 µV and even <200 µV. The two electrodes producing the most prominent icDCs and icHFOs were defined as core electrodes. The correlation between the resected core electrode area and degree of seizure control after surgery was analyzed. icDCs were classified into two types based on a peak latency value cutoff of 8.9 s, and the occurrence rates of both patterns were investigated. RESULTS: icDCs (142/147 seizures [96.6%]) and icHFOs (135/147 seizures [91.8%]) occurred in all patients (100%). Compared with the amplitude of icDCs with TC10s reported in previous studies, the amplitude of icDCs with TC2s was attenuated in the current study. A significant positive correlation was observed between the resected core electrode area and degree of seizure control in both icDCs and icHFOs. A rapid development pattern was observed in 202 of 264 electrodes (76.5%). SIGNIFICANCE: Similar to icDCs with TC10s, those with TC2s were observed adequately. Furthermore, favorable outcomes are expected using TC2s, which is currently available worldwide.

Mature human induced pluripotent stem cell-derived cardiomyocytes promote angiogenesis through alpha-B crystallin.

BACKGROUND: Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) can be used to treat heart diseases; however, the optimal maturity of hiPSC-CMs for effective regenerative medicine remains unclear. We aimed to investigate the benefits of long-term cultured mature hiPSC-CMs in injured rat hearts. METHODS: Cardiomyocytes were differentiated from hiPSCs via monolayer culturing, and the cells were harvested on day 28 or 56 (D28-CMs or D56-CMs, respectively) after differentiation. We transplanted D28-CMs or D56-CMs into the hearts of rat myocardial infarction models and examined cell retention and engraftment via in vivo bioluminescence imaging and histological analysis. We performed transcriptomic sequencing analysis to elucidate the genetic profiles before and after hiPSC-CM transplantation. RESULTS: Upregulated expression of mature sarcomere genes in vitro was observed in D56-CMs compared with D28-CMs. In vivo bioluminescence imaging studies revealed increased bioluminescence intensity of D56-CMs at 8 and 12 weeks post-transplantation. Histological and immunohistochemical analyses showed that D56-CMs promoted engraftment and maturation in the graft area at 12 weeks post-transplantation. Notably, D56-CMs consistently promoted microvessel formation in the graft area from 1 to 12 weeks post-transplantation. Transcriptomic sequencing analysis revealed that compared with the engrafted D28-CMs, the engrafted D56-CMs enriched genes related to blood vessel regulation at 12 weeks post-transplantation. As shown by transcriptomic and western blot analyses, the expression of a small heat shock protein, alpha-B crystallin (CRYAB), was significantly upregulated in D56-CMs compared with D28-CMs. Endothelial cell migration was inhibited by small interfering RNA-mediated knockdown of CRYAB when co-cultured with D56-CMs in vitro. Furthermore, CRYAB overexpression enhanced angiogenesis in the D28-CM grafts at 4 weeks post-transplantation. CONCLUSIONS: Long-term cultured mature hiPSC-CMs promoted engraftment, maturation and angiogenesis post-transplantation in infarcted rat hearts. CRYAB, which was highly expressed in D56-CMs, was identified as an angiogenic factor from mature hiPSC-CMs. This study revealed the benefits of long-term culture, which may enhance the therapeutic potential of hiPSC-CMs.

[Deep Brain Stimulation of Globus Pallidus].

The globus pallidus internus(GPi)has evolved as a potential target for deep brain stimulation(DBS)in patients with advanced Parkinson's disease(PD). GPi stimulation has a significant impact on intractable hyperkinetic movement disorders. Optimal surgical procedures require a combination of image-based targeting and intraoperative microelectrode recording(MER)strategies. Provocation with stimulation through microelectrode or a DBS electrode is also crucial for refining the appropriate electrode position and obtaining a wide therapeutic window of stimulation parameters. In patients with PD, the best target for deep brain stimulation, whether subthalamic nucleus(STN)or the GPi, has been a subject of interest in recent medical literature. STN remains the preferred target for DBS in patients with advanced PD worldwide. In postoperative medication reduction, numerous data support that STN stimulation reduces the total dose of anti-parkinsonian drugs compared to GPi stimulation. However, GPi stimulation has shown a direct anti-dyskinetic effect, without reducing levodopa. Thus, GPi stimulation might be recommended for patients with neurocognitive or neuropsychiatric issues. GPi stimulation has a potential for treating hyperkinetic movement disorders. In patients with PD, STN stimulation is preferred worldwide; however, GPi stimulation has a clinical advantage only for select patients.

Predicting Neurocognitive Change after Bilateral Deep Brain Stimulation of Subthalamic Nucleus for Parkinson's Disease.

OBJECTIVE: Deep brain stimulation (DBS) of the bilateral subthalamic nucleus (STN) is a standard surgical treatment option in patients with advanced Parkinson's disease. Adverse effects on cognitive function have been reported, impacting the quality of life of patients and caregivers. We aimed to investigate a quantitative predictive preexisting cognitive factor for predicting postoperative cognitive changes. METHODS: Thirty-five patients underwent STN-DBS. A battery of neuropsychological tests were used to examine executive function, processing speed, and visuospatial function both preoperatively and 1 year postoperatively. A multiple logistic regression analysis was performed to investigate the relationships between preoperative factors and cognitive outcomes. The predictive value of the preoperative factors for global cognitive decline during long-term follow-up were evaluated. RESULTS: The patients exhibited significant changes in processing speed and visuospatial function after surgery. Using reliable change index values, lower preoperative scores on the Similarities and Object Assembly subtests of the Wechsler Adult Intelligence Scale III were associated with decreases in visuospatial function at 1 year after DBS. The odds ratios were 10.2 for Similarities and 9.53 for Object Assembly. The proportion of Mini Mental State Examination-maintained patients with low scores on the Similarities subtest was significantly lower than that of patients with high scores at 3 and 5 years. No factors were found to be related to decreases in processing speed. CONCLUSIONS: Preoperative evaluation of the Similarities and Object Assembly subtests may be useful to identify patients who are at a greater risk of experiencing decreases in visuospatial functioning after STN-DBS. Furthermore, a low score on the Similarities subtest may predict future global cognitive deterioration.

Predictive potential of preoperative electroencephalogram for neuropsychological change following subthalamic nucleus deep brain stimulation in Parkinson's disease.

BACKGROUND: Deep brain stimulation of the bilateral subthalamic nucleus (STN-DBS) improves motor fluctuation and severe dyskinesia in advanced Parkinson's disease (PD). Effects on non-motor symptoms, such as neurocognitive side effects, can also influence the quality of life of both patients with PD and caregivers. Predictive quantitative factors associated with postoperative neurocognitive deterioration therefore warrant further attention. Here, we evaluated preoperative electroencephalogram (EEG) as a predictive marker for changes in neurocognitive functions after surgery. METHODS: Scalp EEG was recorded preoperatively from 17 patients with PD who underwent bilateral STN-DBS. Global relative power in the theta, alpha, and beta bands was calculated. Cognitive function was assessed with neuropsychological batteries preoperatively and 1 year after STN-DBS. RESULTS: Performance on the Symbol Search subtest of the WAIS III declined 1 year after DBS. The theta band was chosen for analysis with a 40% cutoff point for increased (≥ 40%) and decreased (< 40%) power. No significant differences between the two groups in baseline performance on most neuropsychological batteries were found, except for the Digit Symbol Coding subtest of the WAIS III. Changes in visual spatial functions were significantly different between groups. The increased theta band power group demonstrated a significant deterioration in performance on the WAIS III Matrix Reasoning subtest and the copy and immediate recall tasks of the Rey-Osterrieth complex figure test. CONCLUSIONS: These findings suggest that preoperative increases in theta power are related to postoperative deterioration of visuospatial function, which indicates the predictive potential of preoperative quantitative EEG for neurocognitive changes after STN-DBS.

The Tethered Effect of Vestibular Schwannoma Tumor Shrinkage Following Stereotactic Radiosurgery in Secondary Trigeminal Neuralgia.

BACKGROUND: Compression of the trigeminal nerve by vessels and tumors causes trigeminal neuralgia. However, a tethering effect, provoking an abnormal root-stretching force, has been previously reported to play a role in trigeminal nerve hyperexcitability. We report 2 patients with vestibular schwannomas treated by stereotactic radiosurgery (SRS) who presented with typical manifestations of trigeminal neuralgia after tumor shrinkage. Furthermore, we discuss the mechanisms of trigeminal neuralgia. CASE DESCRIPTION: Two patients without a history of trigeminal dysfunction, including trigeminal neuralgia, underwent SRS for vestibular schwannomas. Both patients demonstrated tumor shrinkage after transient tumor expansion following SRS. Neither patient presented with facial pain or dysesthesia at the time of peak tumor volume. However, trigeminal neuralgia occurred after tumor shrinkage. One patient underwent surgery, as the neuralgia was refractory to medical treatment; although the trigeminal nerve was adhered and tethered to the tumor, no neurovascular conflict was identified between the tumor and the nerve. We removed the tumor partially, dissecting between the nerve and the tumor, and relieved the tethered effect. Trigeminal neuralgia was relieved without medication after surgery. CONCLUSIONS: The present cases demonstrate a tethered effect of tumor shrinkage after SRS, which was considered to play a role in trigeminal neuralgia. Surgical dissection surrounding the nerve root is effective for medically resistant neuralgia, even if the tumor shrinks. Partial tumor removal is adequate in such cases, as the tumor has been controlled by radiosurgery.

Sagittal splitting of the temporalis muscle for encephalo-myo-synangiosis to prevent ischemic complications due to a swollen temporalis muscle without inhibiting collateral developments in patients with moyamoya disease.

OBJECTIVEEncephalo-myo-synangiosis (EMS) is an effective revascularization procedure for the treatment of moyamoya disease (MMD). However, the temporalis muscle used for EMS sometimes swells and causes ischemic complications by compressing the underlying brain. This study aimed to elucidate the effect of sagittal splitting (SS) of the muscle for prevention of ischemic complications and its impact on the postoperative development of collateral vessels.METHODSIn this historical case-control study, we analyzed 60 hemispheres in adult patients with MMD who underwent EMS using the temporalis muscle from December 1998 to November 2017. The muscle was divided anteroposteriorly by coronal splitting, and the anterior, posterior, or both parts of the muscle were used for EMS in 17, 4, and 39 hemispheres, respectively. In cases performed after 2006, the muscle was halved by SS, and the medial half was used for EMS to reduce the muscle volume (n = 47). The degree of postoperative muscle swelling was evaluated by measuring the maximum thickness of the muscle on CT scans obtained 3 to 7 days after surgery. The collateral developments of the anterior deep temporal artery (aDTA), posterior deep temporal artery (pDTA), and middle temporal artery (MTA) were assessed using digital subtraction angiography and MR angiography performed 6 months or more after surgery.RESULTSSS significantly reduced the temporalis muscle thickness from 12.1 ± 5.0 mm to 7.1 ± 3.0 mm (p < 0.01). Neurological deterioration due to the swollen temporalis muscle developed in 4 of the 13 hemispheres without SS (cerebral infarction in 1, reversible neurological deficit in 2, and convulsion in 1) but in none with SS. There were no significant differences in the postoperative collateral developments of the aDTA, pDTA, and MTA between hemispheres with and without SS. The MTA more frequently developed in hemispheres with EMS in which the posterior part of the muscle was used (30/37) than those in which this part was not used (4/16) (p < 0.01).CONCLUSIONSSS of the temporalis muscle might prevent neurological deterioration caused by the swollen temporalis muscle by reducing its volume without inhibiting the development of the collateral vessels.

[Clinical Characteristics of Craniocervical Junction Arteriovenous Fistulas].

OBJECTIVE: Craniocervical junction arteriovenous fistulas(CCJ-AVFs)are extremely rare lesions that may result in both subarachnoid hemorrhage(SAH)and myelopathy. Diagnosis of CCJ-AVF is difficult and may be delayed due to variable clinical features and a spectrum of neuroradiological findings. To elucidate the clinical characteristics of CCJ-AVF, we analyzed the clinical symptoms, neuroimaging findings, and the results of surgical treatment in five patients. RESULTS: Among the five patients, four were diagnosed with dural AVFs, and the remaining patient was diagnosed with radicular AVF. Two of the five patients presented with SAH, and the rest presented with myelopathy. In both the SAH patients, the initial digital subtraction angiography(DSA)failed to reveal the AVFs, and a definitive diagnosis was made only after repeated DSAs. In two of the three myelopathy patients, the diagnosis was delayed because of nonspecific chronic neurological symptoms which resembled a thoracolumbar lesion. Four patients underwent shunt occlusion through direct surgery and demonstrated favorable outcomes. One myelopathy patient, however, demonstrated abrupt onset, associated with progressive neurological deterioration, which resulted in poor prognosis. The magnetic resonance imaging(MRI)findings, which included intramedullary high intensity on a T2 weighted image, flow void, and varix at the cervical cord, were specific for the myelopathy patients. CONCLUSION: A thorough 4-vessel DSA study, including the cervical region, is mandatory for SAH patients whose clots are predominantly in the posterior fossa, and repeated DSA must be considered in cases of unknown origin. CCJ-AVF may cause myelopathy, with symptoms such as urinary dysfunction and/or paraparesis. Screening with a cervical MRI is useful for detecting CCJ-AVF in cases of myelopathy. Emergency radical treatment must be attempted for those patients demonstrating abrupt onset associated with symptoms of progressive deterioration, such as respiratory dysfunction or bulbar palsy.

The Effects of Percutaneous Endoscopic Gastrostomy on Quality of Life in Patients With Dementia.

BACKGROUND: To examine the effects of percutaneous endoscopic gastrostomy (PEG) on quality of life (QOL) in patients with dementia. METHODS: We retrospectively included 53 Japanese community and tertiary hospitals to investigate the relationship between the newly developed PEG and consecutive dementia patients with swallowing difficulty between Jan 1st 2006 and Dec 31st 2008. We set improvements in 1) the level of independent living, 2) pneumonia, 3) peroral intake as outcome measures of QOL and explored the factors associated with these improvements. RESULTS: Till October 31st 2010, 1,353 patients with Alzheimer's dementia (33.1%), vascular dementia (61.7%), dementia with Lewy body disease (2.0%), Pick disease (0.6%) and others were followed-up for a median of 847 days (mean 805 ± 542 days). A total of 509 deaths were observed (mortality 59%) in full-followed patients. After multivariate adjustments, improvement in the level of independent living was observed in milder dementia, or those who can live independently with someone, compared with advanced dementia, characterized by those who need care by someone: Odds Ratio (OR), 3.90, 95% confidence interval (95%CI), 1.59 - 9.39, P = 0.003. Similarly, improvement of peroral intake was noticed in milder dementia: OR, 2.69, 95%CI, 1.17 - 6.17, P = 0.02. Such significant associations were not observed in improvement of pneumonia. CONCLUSIONS: These results suggest that improvement of QOL after PEG insertion may be expected more in milder dementia than in advanced dementia.

Efficacy of ribavirin monotherapy following combination therapy with interferon alfa-2b and ribavirin for patients with chronic hepatitis C.

Reappearance of HCV-RNA followed by exacerbation of biochemical parameters after combination therapy consisting of interferon and ribavirin is an obstacle to achieve sustained response and improve long-term prognosis. We hypothesed that ribavirin monotherapy after 6 months of combination therapy may improve sustained viral and biochemical responses, and conducted a prospective, randomized and controlled study. Thirty-eight patients with chronic hepatitis C treated with combination therapy for 6 months and had no detectable serum HCV-RNA were enrolled, and allocated into two arms. Group I (n=19) was continuously administered oral ribavirin for additional 6 months, and group II (n=19) was followed up without any further treatment. At the end of trial, HCV-RNA negativity was 11/19 (58%) in group I, and 6/19 (32%) in group II (p=0.191). Multivariant analysis demonstrated that ribavirin monotherapy was not a predictor for the eradication of HCV-RNA. In cases without sustained viral responses, serum ALT levels at baseline and the end of 48 weeks' trial were 54.6 and 44.4 in group I (p=0.237), and significant reduction with ribavirin monotherapy was not observed. In conclusion, ribavirin monotherapy following combination therapy fails to improve sustained viral response as well as biochemical response.