Transplanted Human Neural Progenitor Cells Attenuate Motor Dysfunction and Lengthen Longevity in a Rat Model of Ataxia.

The spastic Han Wistar (sHW) rat serves as a model for human ataxia presenting symptoms of motor deterioration, weight loss, shortened lifespan, and Purkinje neuron loss. Past studies revealed that human neural progenitor cells (NPCs) improved ataxic symptoms at 20 d posttransplantation in sHW rats. In this study, we investigated the fate and longer-term effectiveness of these transplanted NPCs. Rats were placed into four treatment groups: an untreated normal control group (n = 10), an untreated mutant rat control (n = 10), a mutant group that received an injection of dead NPCs (n = 9), and a mutant group that received live NPCs (n = 10). Bilateral cerebellar injections containing 500,000 of either live or dead NPCs were performed on mutant sHW rats at 40 d of age. Motor activity for all mutant rats started to decline in open field testing around day 35. However, at day 45, the live NPC-treated mutants exhibited significant improvements in open field activity. Similar improvements were observed during rotarod testing and weight gain through the completion of the experiments (100 d). Immunohistochemistry revealed few surviving human NPCs in the cerebella of 80- and 100-d-old NPC-treated mutants; while cresyl violet staining revealed that live NPC-treated mutants had significantly more surviving Purkinje neurons compared to mutants that were untreated or received dead NPCs. Direct stereotactic implantation of NPCs alleviated the symptoms of ataxia, acting as a neuroprotectant, supporting future clinical applications of these NPCs in the areas of ataxia as well as other neurodegenerative diseases.

Carbohydrate quality and quantity and risk of coronary heart disease among US women and men.

Background: The carbohydrate-to-fiber ratio is a recommended measure of carbohydrate quality; however, its relation to incident coronary heart disease (CHD) is not currently known. Objective: We aimed to assess the relation between various measures of carbohydrate quality and incident CHD. Design: Data on diet and lifestyle behaviors were prospectively collected on 75,020 women and 42,865 men participating in the Nurses' Health Study (NHS) and the Health Professionals Follow-Up Study (HPFS) starting in 1984 and 1986, respectively, and every 2-4 y thereafter until 2012. All participants were free of known diabetes mellitus, cancer, or cardiovascular disease at baseline. Cox proportional hazards regression models were used to assess the relation between dietary measures of carbohydrate quality and incident CHD. Results: After 1,905,047 (NHS) and 921,975 (HPFS) person-years of follow-up, we identified 7,320 cases of incident CHD. In models adjusted for age, lifestyle behaviors, and dietary variables, the highest quintile of carbohydrate intake was not associated with incident CHD (pooled-RR = 1.04; 95% CI: 0.96, 1.14; P-trend = 0.31). Total fiber intake was not associated with risk of CHD (pooled-RR = 0.94; 95% CI: 0.85, 1.03; P-trend = 0.72), while cereal fiber was associated with a lower risk for incident CHD (pooled-RR = 0.80; 95% CI: 0.74, 0.87; P-trend < 0.0001). In fully adjusted models, the carbohydrate-to-total fiber ratio was not associated with incident CHD (pooled-RR = 1.04; 95% CI: 0.96, 1.13; P-trend = 0.46). However, the carbohydrate-to-cereal fiber ratio and the starch-to-cereal fiber ratio were associated with an increased risk for incident CHD (pooled-RR = 1.20; 95% CI: 1.11, 1.29; P-trend < 0.0001, and pooled-RR = 1.17; 95%CI: 1.09, 1.27; P-trend < 0.0001, respectively). Conclusion: Dietary cereal fiber appears to be an important component of carbohydrate quality. The carbohydrate-to-cereal fiber ratio and the starch-to-cereal fiber ratio, but not the carbohydrate-to-fiber ratio, was associated with an increased risk for incident CHD. Future research should focus on how various measures of carbohydrate quality are associated with CHD prevention. This trial was registered at clinicaltrials.gov as NCT03214861.

Structural Stability of the Coiled-Coil Domain of Tumor Susceptibility Gene (TSG)-101.

The tumor susceptibility gene-101 coiled coil domain (TSG101cc) is an integral component of the endosomal maturation machinery and cytokinesis, and also interacts with several transcription factors. The TSG101cc has been crystallized as a homotetramer but is known to interact with two of its binding partners as a heterotrimer. To investigate this apparent discrepancy, we examined the solution thermodynamics of the TSG101cc. Here, we use circular dichroism, differential scanning calorimetry, analytical ultracentrifugation, fluorescence, and structural thermodynamic analysis to investigate the structural stability and the unfolding of the TSG101cc. We demonstrate that TSG101cc exists in solution primarily as a tetramer, which unfolds in a two-state manner. Surprisingly, no homodimeric or homotrimeric species were detected. Structural thermodynamic analysis of the homotetrameric structure and comparison with known oligomeric coiled-coils suggests that the TSG101cc homotetramer is comparatively unstable on a per residue basis. Furthermore, the homotrimeric coiled-coil is predicted to be much less stable than the functional heterotrimeric coiled-coil in the endosomal sorting complex required for transport 1 (ESCRT1). These results support a model whereby the tetramer-monomer equilibrium of TSG101 serves as the cellular reservoir of TSG101, which is effectively outcompeted when its binding partners are present and the heteroternary complex can form.

Transplantation of Human Neural Progenitor Cells Reveals Structural and Functional Improvements in the Spastic Han-Wistar Rat Model of Ataxia.

The use of regenerative medicine to treat nervous system disorders like ataxia has been proposed to either replace or support degenerating neurons. In this study, we assessed the ability of human neural progenitor cells (hNPCs) to repair and restore the function of dying neurons within the spastic Han-Wistar rat (sHW), a model of ataxia. The sHW rat suffers from neurodegeneration of specific neurons, including cerebellar Purkinje cells and hippocampal CA3 pyramidal cells leading to the observed symptoms of forelimb tremor, hind-leg rigidity, gait abnormality, motor incoordination, and a shortened life span. To alleviate the symptoms of neurodegeneration and to replace or augment dying neurons, neuronal human progenitor cells were implanted into the sHW rats. At 30 d of age, male sHW mutant rats underwent subcutaneous implantation of an Alzet osmotic pump that infused cyclosporine (15 mg/kg/d) used to suppress the rat's immune system. At 40 d, sHW rats received bilateral injections (500,000 cells in 5 µL media) of live hNPCs, dead hNPCs, live human embryonic kidney cells, or growth media either into the cerebellar cortex or into the hippocampus. To monitor results, motor activity scores (open-field testing) and weights of the animals were recorded weekly. The sHW rats that received hNPC transplantation into the cerebellum, at 60 d of age, displayed significantly higher motor activity scores and sustained greater weights and longevities than control-treated sHW rats or any hippocampal treatment group. In addition, cerebellar histology revealed that the transplanted hNPCs displayed signs of migration and signs of neuronal development in the degenerated Purkinje cell layer. This study revealed that implanted human progenitor cells reduced the ataxic symptoms in the sHW rat, identifying a future clinical use of these progenitor cells against ataxia and associated neurodegenerative diseases.

Efficacy of Two Delivery Routes for Transplanting Human Neural Progenitor Cells (NPCs) Into the Spastic Han-Wistar Rat, a Model of Ataxia.

An emerging avenue for recalcitrant neurodegenerative disease treatment is neural progenitor cell (NPC) transplantation. In this study, we investigated the effectiveness of two different delivery routes of human-derived NPC inoculation: injection into the common carotid artery or unilateral stereotactic implantation into the degenerating cerebellum and hippocampus of spastic Han-Wistar (sHW) rats, a model of ataxia. At 30 days of age, sHW mutants were implanted with osmotic pumps preloaded with cyclosporine. Ten days after pump implantation, the animals were given either 3,000,000 live human-derived NPCs (hNPCs; n = 12) or 3,000,000 dead NPCs (dNPCs; n = 12) injected into the common carotid artery, or were given two unilateral implantations of 500,000 hNPCs into the cerebellum and 500,000 hNPCs into the hippocampus of each sHW rat (n = 12) or 500,000 dNPCs by unilateral implantation into the cerebellum and hippocampus (n = 12). We also compared treated sHW rats to untreated sHW rats: normal rats (n = 12) and sibling sHW rats (n = 12). Motor activity and animal weights were monitored every 5 days to ascertain effectiveness of the two types of delivery methods compared to the untreated mutant and normal animals. Mutant rats with hNPC implantations, but not dNPC or carotid artery injections, showed significant deceleration of motor deterioration (p < 0.05). These mutants with hNPC implantations also retained weight longer than dNPC mutants did (p < 0.05). At the end of the experiment, animals were sacrificed for histological evaluation. Using fluorescent markers (Qtracker) incorporated into the hNPC prior to implantation and human nuclear immunostaining, we observed few hNPCs in the brains of carotid artery-injected mutants. However, significant numbers of surviving hNPCs were seen using these techniques in mutant cerebellums and hippocampi implanted with hNPC. Our results show that direct implantation of hNPCs reduced ataxic symptoms in the sHW rat, demonstrating that stereotactic route of stem cell delivery correlates to improved clinical outcomes.

Discordance between echocardiography and MRI in the assessment of mitral regurgitation severity: a prospective multicenter trial.

BACKGROUND: The decision to undergo mitral valve surgery is often made on the basis of echocardiographic criteria and clinical assessment. Recent changes in treatment guidelines recommending surgery in asymptomatic patients make the accurate assessment of mitral regurgitation (MR) severity even more important. OBJECTIVES: The purpose of this study was to compare echocardiography and magnetic resonance imaging (MRI) in the assessment of MR severity using the degree of left ventricular (LV) remodeling after surgery as the reference standard. METHODS: In this prospective multicenter trial, MR severity was assessed in 103 patients using both echocardiography and MRI. Thirty-eight patients subsequently had isolated mitral valve surgery, and 26 of these had an additional MRI performed 5 to 7 months after surgery. The pre-surgical estimate of regurgitant severity was correlated with the postoperative decrease in LV end-diastolic volume. RESULTS: Agreement between MRI and echocardiographic estimates of MR severity was modest in the overall cohort (r = 0.6; p < 0.0001), and there was a poorer correlation in the subset of patients sent for surgery (r = 0.4; p = 0.01). There was a strong correlation between post-surgical LV remodeling and MR severity as assessed by MRI (r = 0.85; p < 0.0001), and no correlation between post-surgical LV remodeling and MR severity as assessed by echocardiography (r = 0.32; p = 0.1). CONCLUSIONS: The data suggest that MRI is more accurate than echocardiography in assessing the severity of MR. MRI should be considered in those patients when MR severity as assessed by echocardiography is influencing important clinical decisions, such as the decision to undergo MR surgery.

Multiple osteocartilaginous exostoses of the lower extremity: a case report.

An osteochrondoma is a benign osseous tumor capped by cartilage. Osteochondromas occurring at the distal tibia and fibula are uncommon and even more so when occurring at the first metatarsal head. Osteochondromas usually occur at the metaphysis of long bones; however, they can occur at other cortical bone metaphyses. This is a case report of a 54-year-old male with incidental radiographic findings of multiple osteochondromas around his ankles as well as a solitary osteochondromatous lesion growing proximally off the left first metatarsal head. The multiple osteochrondomas were evident on multiple views, and subsequent histological analysis of the solitary osteochondromatous lesion via total surgical excision confirmed a diagnosis of multiple hereditary osteochrondromatosis.

Significance of a positive family history for coronary heart disease in patients with a zero coronary artery calcium score (from the Multi-Ethnic Study of Atherosclerosis).

Although a coronary artery calcium (CAC) score of 0 is associated with a very low 10-year risk for cardiac events, this risk is nonzero. Subjects with a family history of coronary heart disease (CHD) has been associated with more subclinical atherosclerosis than subjects without a family history of CHD. The purpose of this study was to assess the significance of a family history for CHD in subjects with a CAC score of 0. The Multi-Ethnic Study of Atherosclerosis cohort includes 6,814 participants free of clinical cardiovascular disease (CVD) at baseline. Positive family history was defined as reporting a parent, sibling, or child who had a heart attack. Time to incident CHD or CVD event was modeled using the multivariable Cox regression; 3,185 subjects were identified from the original Multi-Ethnic Study of Atherosclerosis cohort as having a baseline CAC score of 0 (mean age 58 years, 37% men). Over a median follow-up of 10 years, 101 participants (3.2%) had CVD events and 56 (1.8%) had CHD events. In age- and gender-adjusted analyses, a family history of CHD was associated with an ∼70% increase in CVD (hazard ratio 1.73, 95% confidence interval 1.17 to 2.56) and CHD (hazard ratio 1.72, 95% confidence interval 1.01 to 2.91) events. CVD events remained significant after further adjustment for ethnicity, risk factors, and baseline medication use. In conclusion, asymptomatic subjects with a 0 CAC score and a positive family history of CHD are at increased risk for CVD and CHD events compared with those without a family history of CHD, although absolute event rates remain low.

Dopamine as an anorectic neuromodulator in the cockroach Rhyparobia maderae.

Insects, including cockroaches, self-select a balanced diet when faced with different nutrient choices. For self-selection to be carried out effectively, insects possess neuroregulatory systems to control their food intake. In the present study, we examined the role of the neurotransmitter dopamine (DA) in the feeding regulation of the Madeira cockroach (Rhyparobia maderae). When R. maderae nymphs were injected with 20 µl of 100 mmol l(-1) DA, they showed an 83.3% reduction in sucrose intake and a 78.9% reduction in total intake compared with saline-injected controls. The DA agonist, 2-amino-6,7-dihydroxy-1,2,3,4-tetrahydronaphthalene (6,7-ADTN) (100 mmol l(-1) in 1 µl), caused a significant reduction in sucrose feeding, reducing feeding by 47.3% compared with saline-injected controls. Protein feeding was also significantly reduced by 6,7-ADTN to 62%. Rhyparobia maderae nymphs injected with the DA antagonist chlorpromazine (100 mmol l(-1) in 1 µl) did not differ significantly from control nymphs in their feeding behavior. Interestingly, R. maderae nymphs injected with 2 µl or 5 µl chlorpromazine (100 mmol l(-1)) showed significantly increased mortality rates of 47.5% or 66.7%, respectively. The DA antagonist, spiperone (100 mmol l(-1) in 1 µl), caused a significant feeding response, showing an increase in feeding in both sucrose (310.6%) and total intake (236.3%). Casein feeding in R. maderae nymphs was also elevated (70.8%) but this was not statistically significant. The experiments with DA, the DA agonist 6,7-ADTN and the DA antagonist spiperone strongly suggest that the neurotransmitter DA is involved in regulating feeding in the cockroach R. maderae.

Characterization of chronic nicotine exposure on the survival of the spastic Han-Wistar rat.

Excitotoxicity has been implicated as a mechanism of cell death in many neurodegenerative disorders. Cell culture studies have shown that neuroprotection can be induced by preincubation with the acetylcholine agonist nicotine. We investigated the possible neuroprotective effects of nicotine in the spastic Han-Wistar rat, which suffers from glutamate excitotoxicity affecting two central nervous system regions: The hippocampus and the cerebellum. To investigate nicotine's possible neuroprotection, we treated 25-day-old mutant and normal siblings with 50-75 mg/l nicotine in their drinking solutions. The 75-ml/l dose significantly improved motor activity and increased longevity of the mutants (p<.05). To assess whether nicotine protected individual neurons, we performed hematoxylin and eosin (H&E) staining of brain sections. The histological data indicated that nicotine increased the survival of Purkinje cells in the mutants by as much as 50% but did not prevent cell death. To investigate whether the neuroprotection by nicotine was due to changes in nicotinic receptor expression, we performed immunohistochemical studies by staining for the alpha 3, alpha 4, and alpha 7 receptor subunits in mutant and normal rats. The alpha 4 subunit was upregulated by nicotine treatment in the cerebellum and was noted to have lower levels throughout the hippocampus of mutant animals. The alpha 3 and alpha 7 subunits showed no change in expression among all groups.

Enhanced epileptogenic susceptibility in a genetic model of reactive synaptogenesis: the spastic Han-Wistar rat.

Our laboratory has been studying the spastic Han-Wistar (sHW) rat as a model of neuronal degeneration. Mutant sHW rats display a number of developmental abnormalities that eventually lead to hippocampal pyramidal cell death and synaptic reorganization starting around 30 days of age. The present study examined the contribution of hippocampal reorganization to the expression of seizures induced by systemic injections of kainic acid. Behavioral observations, EEG recordings and hippocampal Fos protein expression in these animals indicated that mutants develop paroxysmal discharges and seizures earlier than controls and the intensity of epileptic manifestations is greater. Kainate injections were lethal in 50% of mutants compared to only 5% of controls. Fos expression was increased approximately twofold in the mutant hippocampus, implicating abnormal excitation in this region. Additional studies in untreated animals indicated that GluR2 mRNA expression was significantly increased throughout the hippocampus in mutant animals, possibly contributing to the enhanced susceptibility to kainate treatment. These results confirm the role of synaptic reorganization in the increased propensity to develop epileptic discharges. Our data also underscore the usefulness of this natural model of cell degeneration and reactive synaptogenesis for understanding the mechanisms of neuronal hyperexcitability.