Loss of GTF2I promotes neuronal apoptosis and synaptic reduction in human cellular models of neurodevelopment

Individuals with Williams syndrome (WS), a neurodevelopmental disorder caused by hemizygous loss of 26-28 genes at 7q11.23, characteristically portray a hypersocial phenotype. Copy-number variations and mutations in one of these genes, GTF2I, are associated with altered sociality and are proposed to underlie hypersociality in WS. However, the contribution of GTF2I to human neurodevelopment remains poorly understood. Here, human cellular models of neurodevelopment, including neural progenitors, neurons, and three-dimensional cortical organoids, are differentiated from CRISPR-Cas9-edited GTF2I-knockout (GTF2I-KO) pluripotent stem cells to investigate the role of GTF2I in human neurodevelopment. GTF2I-KO progenitors exhibit increased proliferation and cell-cycle alterations. Cortical organoids and neurons demonstrate increased cell death and synaptic dysregulation, including synaptic structural dysfunction and decreased electrophysiological activity on a multielectrode array. Our findings suggest that changes in synaptic circuit integrity may be a prominent mediator of the link between alterations in GTF2I and variation in the phenotypic expression of human sociality.

Impact of alcohol exposure on neural development and network formation in human cortical organoids

Prenatal alcohol exposure is the foremost preventable etiology of intellectual disability and leads to a collection of diagnoses known as Fetal Alcohol Spectrum Disorders (FASD). Alcohol (EtOH) impacts diverse neural cell types and activity, but the precise functional pathophysiological effects on the human fetal cerebral cortex are unclear. Here, we used human cortical organoids to study the effects of EtOH on neurogenesis and validated our findings in primary human fetal neurons. EtOH exposure produced temporally dependent cellular effects on proliferation, cell cycle, and apoptosis. In addition, we identified EtOH-induced alterations in post-translational histone modifications and chromatin accessibility, leading to impairment of cAMP and calcium signaling, glutamatergic synaptic development, and astrocytic function. Proteomic spatial profiling of cortical organoids showed region-specific, EtOH-induced alterations linked to changes in cytoskeleton, gliogenesis, and impaired synaptogenesis. Finally, multi-electrode array electrophysiology recordings confirmed the deleterious impact of EtOH on neural network formation and activity in cortical organoids, which was validated in primary human fetal tissues. Our findings demonstrate progress in defining the human molecular and cellular phenotypic signatures of prenatal alcohol exposure on functional neurodevelopment, increasing our knowledge for potential therapeutic interventions targeting FASD symptoms.

Using a Hybrid Approach to Increase the Impact of Medical Response to Natural Disasters

The United Nations (UN) established an umbrella of organizations to manage distinct clusters of humanitarian aid. The World Health Organization (WHO) oversees the health cluster, giving it responsibility for global, national, and local medical responses to natural disasters. However, this centralized structure insufficiently engages local players, impeding robust local implementation. The Gorkha earthquake struck Nepal on April 25, 2015, becoming Nepal's most severe natural disaster since the 1934 Nepal-Bihar earthquake. In coordinated response, 2 organizations, Empower Nepali Girls and International Neurosurgical Children's Association, used a hybrid approach integrating continuous communication with local recipients. Each organization mobilized its principal resource strengths-material medical supplies or human capital-thereby efficiently deploying resources to maximize the impact of the medical response. In addition to efficient resource use, this approach facilitates dynamic medical responses from highly mobile organizations. Importantly, in addition to future earthquakes in Nepal, this medical response strategy is easily scalable to other natural disaster contexts and other medical relief organizations. Preemptively identifying partner organizations with complementary strengths, continuous engagement with recipient populations, and creating disaster- and region-specific response teams may represent viable variations of the WHO cluster model with greater efficacy in local implementation of treatment in acute disaster scenarios.

Multimodal monitoring of human cortical organoids implanted in mice reveal functional connection with visual cortex

Human cortical organoids, three-dimensional neuronal cultures, are emerging as powerful tools to study brain development and dysfunction. However, whether organoids can functionally connect to a sensory network in vivo has yet to be demonstrated. Here, we combine transparent microelectrode arrays and two-photon imaging for longitudinal, multimodal monitoring of human cortical organoids transplanted into the retrosplenial cortex of adult mice. Two-photon imaging shows vascularization of the transplanted organoid. Visual stimuli evoke electrophysiological responses in the organoid, matching the responses from the surrounding cortex. Increases in multi-unit activity (MUA) and gamma power and phase locking of stimulus-evoked MUA with slow oscillations indicate functional integration between the organoid and the host brain. Immunostaining confirms the presence of human-mouse synapses. Implantation of transparent microelectrodes with organoids serves as a versatile in vivo platform for comprehensive evaluation of the development, maturation, and functional integration of human neuronal networks within the mouse brain.

SARS-CoV-2 infects human brain organoids causing cell death and loss of synapses that can be rescued by treatment with Sofosbuvir

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19), which was rapidly declared a pandemic by the World Health Organization (WHO). Early clinical symptomatology focused mainly on respiratory illnesses. However, a variety of neurological manifestations in both adults and newborns are now well-documented. To experimentally determine whether SARS-CoV-2 could replicate in and affect human brain cells, we infected iPSC-derived human brain organoids. Here, we show that SARS-CoV-2 can productively replicate and promote death of neural cells, including cortical neurons. This phenotype was accompanied by loss of excitatory synapses in neurons. Notably, we found that the U.S. Food and Drug Administration (FDA)-approved antiviral Sofosbuvir was able to inhibit SARS-CoV-2 replication and rescued these neuronal alterations in infected brain organoids. Given the urgent need for readily available antivirals, these results provide a cellular basis supporting repurposed antivirals as a strategic treatment to alleviate neurocytological defects that may underlie COVID-19- related neurological symptoms.

Junctional instability in neuroepithelium and network hyperexcitability in a focal cortical dysplasia human model

Focal cortical dysplasia is a highly epileptogenic cortical malformation with few treatment options. Here, we generated human cortical organoids from patients with focal cortical dysplasia type II. Using this human model, we mimicked some focal cortical dysplasia hallmarks, such as impaired cell proliferation, the presence of dysmorphic neurons and balloon cells, and neuronal network hyperexcitability. Furthermore, we observed alterations in the adherens junctions zonula occludens-1 and partitioning defective 3, reduced polarization of the actin cytoskeleton, and fewer synaptic puncta. Focal cortical dysplasia cortical organoids showed downregulation of the small GTPase RHOA, a finding that was confirmed in brain tissue resected from these patients. Functionally, both spontaneous and optogenetically-evoked electrical activity revealed hyperexcitability and enhanced network connectivity in focal cortical dysplasia organoids. Taken together, our findings suggest a ventricular zone instability in tissue cohesion of neuroepithelial cells, leading to a maturational arrest of progenitors or newborn neurons, which may predispose to cellular and functional immaturity and compromise the formation of neural networks in focal cortical dysplasia.

Pharmacological reversal of synaptic and network pathology in human MECP2-KO neurons and cortical organoids

Duplication or deficiency of the X-linked MECP2 gene reliably produces profound neurodevelopmental impairment. MECP2 mutations are almost universally responsible for Rett syndrome (RTT), and particular mutations and cellular mosaicism of MECP2 may underlie the spectrum of RTT symptomatic severity. No clinically approved treatments for RTT are currently available, but human pluripotent stem cell technology offers a platform to identify neuropathology and test candidate therapeutics. Using a strategic series of increasingly complex human stem cell-derived technologies, including human neurons, MECP2-mosaic neurospheres to model RTT female brain mosaicism, and cortical organoids, we identified synaptic dysregulation downstream from knockout of MECP2 and screened select pharmacological compounds for their ability to treat this dysfunction. Two lead compounds, Nefiracetam and PHA 543613, specifically reversed MECP2-knockout cytologic neuropathology. The capacity of these compounds to reverse neuropathologic phenotypes and networks in human models supports clinical studies for neurodevelopmental disorders in which MeCP2 deficiency is the predominant etiology.

Successful treatment of highly recurrent facial baroparesis in a frequent high-altitude traveler: a case report

Background

Facial baroparesis is a palsy of the seventh cranial nerve resulting from increased pressure compressing the nerve along its course through the middle ear cavity. It is a rare condition, most commonly reported in barotraumatic environments, in particular scuba diving and high-altitude air travel. We report here an unusual case of highly frequent baroparesis, workup, and successful treatment.

Case presentation

A 57-year-old Caucasian male frequent commercial airline traveler presented with a 4-year history of recurrent episodes of right-sided facial paralysis and otalgia, increasing in both frequency and severity. Incidents occurred almost exclusively during rapid altitude changes in aircraft, mostly ascent, but also during rapid altitude change in an automobile. Self-treatment included nasal and oral decongestants, nasal corticosteroids, and warm packs. Temporal bone computed tomography (CT) scan revealed possible right-sided dehiscence of the tympanic bone segment; audiogram and magnetic resonance imaging of the internal auditory canals were unremarkable. After a diagnosis of facial nerve baroparesis was made, the patient underwent myringotomy with insertion of a pressure equalization tube (PET) into the right tympanic membrane. Despite re-exposure to altitude change multiple times weekly post-treatment, the patient reported being symptom-free for more than 6 months following intervention.

Conclusions

Prompt PET insertion may represent the preferred treatment for individuals who suffer recurrent episodes of facial baroparesis. Education regarding this rare condition may prevent unnecessary testing and treatment of affected patients. Future studies should explore the pathophysiology and risk factors, compare therapeutic options, and provide follow-up data to optimize the management of affected patients.

Brain Organoids as Tools for Modeling Human Neurodevelopmental Disorders

Brain organoids recapitulate in vitro the specific stages of in vivo human brain development, thus offering an innovative tool by which to model human neurodevelopmental disease. We review here how brain organoids have been used to study neurodevelopmental disease and consider their potential for both technological advancement and therapeutic development.

Lewy Body Pathology and Chronic Traumatic Encephalopathy Associated With Contact Sports

Traumatic brain injury has been associated with increased risk of Parkinson disease and parkinsonism, and parkinsonism and Lewy body disease (LBD) can occur with chronic traumatic encephalopathy (CTE). To test whether contact sports and CTE are associated with LBD, we compared deceased contact sports athletes (n = 269) to cohorts from the community (n = 164) and the Boston University Alzheimer disease (AD) Center (n = 261). Participants with CTE and LBD were more likely to have β-amyloid deposition, dementia, and parkinsonism than CTE alone (p < 0.05). Traditional and hierarchical clustering showed a similar pattern of LBD distribution in CTE compared to LBD alone that was most frequently neocortical, limbic, or brainstem. In the community-based cohort, years of contact sports play were associated with neocortical LBD (OR = 1.30 per year, p = 0.012), and in a pooled analysis a threshold of >8 years of play best predicted neocortical LBD (ROC analysis, OR = 6.24, 95% CI = 1.5-25, p = 0.011), adjusting for age, sex, and APOE ɛ4 allele status. Clinically, dementia was significantly associated with neocortical LBD, CTE stage, and AD; parkinsonism was associated with LBD pathology but not CTE stage. Contact sports participation may increase risk of developing neocortical LBD, and increased LBD frequency may partially explain extrapyramidal motor symptoms sometimes observed in CTE.

Spray droplet size and carrier volume effect on dicamba and glufosinate efficacy

BACKGROUND

Pesticide applications using a specific droplet size and carrier volume could maximize herbicide efficacy while mitigating particle drift in a precise and efficient manner. The objectives of this study were to investigate the influence of spray droplet size and carrier volume on dicamba and glufosinate efficacy, and to determine the plausibility of droplet-size based site-specific weed management strategies.

RESULTS

Generally, across herbicides and carrier volumes, as droplet size increased, weed control decreased. Increased carrier volume (187 L ha-1 ) buffered this droplet size effect, thus greater droplet sizes could be used to mitigate drift potential while maintaining sufficient levels of weed control. To mitigate drift potential and achieve satisfactory weed control (≥ 90% of maximum observed control), a 900 µm (Ultra Coarse) droplet size paired with 187 L ha-1 carrier volume is recommended for dicamba applications and a 605 µm (Extremely Coarse) droplet size across carrier volumes is recommended for glufosinate applications. Although general droplet size recommendations were created, optimum droplet sizes for weed control varied significantly across site-years.

CONCLUSION

Convoluted interactions occur between droplet size, carrier volume, and other application parameters. Recommendations for optimizing herbicide applications based on droplet size should be based on a site-specific management approach to better account for these interactions. © 2018 Society of Chemical Industry.

Tuberculosis screening among HIV-infected patients: tuberculin skin test vs. interferon-gamma release assay

National guidelines recommend screening for latent tuberculosis infection (LTBI) in all HIV-infected patients. Thus, the objective of this study was to measure protocol adherence to national guidelines regarding LTBI screening for HIV-infected patients entering care at an urban primary care clinic specializing in HIV care, identify clinical and other characteristics associated with adherence, and determine whether transitioning from the tuberculin skin test (TST) to the interferon-gamma release assay (IGRA) improved adherence. We conducted a retrospective study using protocol adherence to LTBI screening guidelines within twelve months of entering care at an HIV clinic as the primary outcome. Successful protocol adherence was defined as the placement and reading of a TST, performance of an IGRA, or a note in study clinic records documenting prior testing or treatment for tuberculosis in an outside setting. Multivariable modified Poisson regression models were used in analyses. Overall, 32% (n = 118/372) of patients received LTBI screening within twelve months of entering care. Protocol adherence to LTBI screening guidelines increased from 28% to 37% following the transition from TST to IGRA screening. IGRA screening [adjusted prevalence ratio: 1.45, 95% confidence limits: (1.07, 1.96)], male sex [1.47 (1.05, 2.07)], transfer patient status [1.51 (1.05, 2.18)], and greater than one year of clinic attendance [1.62 (1.06, 2.48)] were independently associated with protocol adherence. Among patients without prior LTBI screening or treatment, patients entering the clinic in 2013 under the IGRA screening protocol were more likely to be screened for LTBI compared to patients entering under the TST screening protocol (34.3% vs. 9.7%, p < 0.001). In conclusion, transitioning from TST to IGRA-based screening improved adherence to screening guidelines. However, further work on improving adherence to LTBI screening guidelines among HIV-infected patients is needed.

The effects of age on the learning and forgetting of primacy, middle, and recency components of a multi-trial word list

The serial position effect reveals that recall of a supraspan list of words follows a predictable pattern, whereby words at the beginning (primacy) and end (recency) of a list are recalled more easily than words in the middle. This effect has typically been studied using single list-learning trials, but in neuropsychology, multi-trial list-learning tests are more commonly used. The current study examined trends in learning for primacy, middle, and recency effects across multiple trials in younger and older age cohorts. Participants were 158 volunteers, including 79 adults aged 17-36 ("younger" group) and 79 adults aged 54-89 years ("older" group). Each participant completed four learning trials and one delayed (5-10 min) recall trial from the Memory Assessment Scales. Scores were divided into primacy (first four words), middle (middle four words), and recency (final four words) scores for all trials. For list acquisition, mixed effects modeling examined the main effects of and interactions between learning slope (logarithmic), age group, and serial position. Rate of learning increased logarithmically over four trials and varied by serial position, with growth of middle and recency word acquisition increasing more rapidly than recall of primacy words; this interaction did not differ by age group. Delayed retention differed according to age group and serial position; both older and younger adults demonstrated similar retention for primacy words, but older adults showed reduced retention for middle and recency words. Although older adults acquired less information across learning trials, the reason for this reduced acquisition was related to initial learning, not to rate of learning over time. Older compared to younger adults were less efficient at transferring middle and recency words from short-term to long-term memory.

Assessing clinicopathological correlation in chronic traumatic encephalopathy: rationale and methods for the UNITE study

INTRODUCTION

Chronic traumatic encephalopathy (CTE) is a progressive neurodegeneration associated with repetitive head impacts. Understanding Neurologic Injury and Traumatic Encephalopathy (UNITE) is a U01 project recently funded by the National Institute of Neurological Disorders and Stroke and the National Institute of Biomedical Imaging and Bioengineering. The goal of the UNITE project is to examine the neuropathology and clinical presentation of brain donors designated as "at risk" for the development of CTE based on prior athletic or military exposure. Here, we present the rationale and methodology for UNITE.

METHODS

Over the course of 4 years, we will analyze the brains and spinal cords of 300 deceased subjects who had a history of repetitive head impacts sustained during participation in contact sports at the professional or collegiate level or during military service. Clinical data are collected through medical record review and retrospective structured and unstructured family interviews conducted by a behavioral neurologist or neuropsychologist. Blinded to the clinical data, a neuropathologist conducts a comprehensive assessment for neurodegenerative disease, including CTE, using published criteria. At a clinicopathological conference, a panel of physicians and neuropsychologists, blinded to the neuropathological data, reaches a clinical consensus diagnosis using published criteria, including proposed clinical research criteria for CTE.

RESULTS

We will investigate the validity of these clinical criteria and sources of error by using recently validated neuropathological criteria as a gold standard for CTE diagnosis. We also will use statistical modeling to identify diagnostic features that best predict CTE pathology.

CONCLUSIONS

The UNITE study is a novel and methodologically rigorous means of assessing clinicopathological correlation in CTE. Our findings will be critical for developing future iterations of CTE clinical diagnostic criteria.

Base rate of performance invalidity among non-clinical undergraduate research participants

Neuropsychological research frequently uses non-clinical undergraduate participants to evaluate neuropsychological tests. However, a recent study by An and colleagues (2012, Archives of Clinical Neuropsychology, 27, 849-857) called into question that the extent to which the interpretation of these participants' performance on neuropsychological tests is valid. This study found that in a sample of 36 participants, 55.6% exhibited performance invalidity at an initial session and 30.8% exhibited performance invalidity at a follow-up session. The current study attempted to replicate these findings in a larger, more representative sample using a more rigorous methodology. Archival data from 133 non-clinical undergraduate research participants were analyzed. Participants were classified as performance invalid if they failed any one PVT. In the current sample, only 2.26% of participants exhibited performance invalidity. Thus, concerns regarding insufficient effort and performance invalidity when using undergraduate research participants appear to be overstated.

The δ latent dementia phenotype in the uniform data set: Cross-validation and extension

OBJECTIVE

Royall and colleagues identified a latent dementia phenotype, "δ", reflecting the "cognitive correlates of functional status." We sought to cross-validate and extend these findings in a large clinical case series of adults with and without dementia.

METHOD

A confirmatory factor analysis (CFA) model for δ was fit to National Alzheimer's Coordinating Center data (n = 26,068). Factor scores derived from δ were compared with the Clinical Dementia Rating Sum of Boxes (CDR-SB) and to clinically diagnosed dementia. A longitudinal parallel-process growth model compared changes in δ with changes in CDR-SB over 6 annual evaluations.

RESULTS

The CFA model fit well; CFI = 0.971, RMSEA = 0.070. Factor scores derived from δ discriminated between demented and nondemented participants with an area under the curve of .96. The growth model also fit well, CFI = 0.969, RMSEA = 0.032.

CONCLUSIONS

The δ construct represents a novel approach to measuring dementia-related changes and has potential to improve cognitive assessment of neurodegenerative diseases.

Abstract P2-05-06: Quantitative measurement of HER2 expression in breast cancers: comparison with “real world” HER2 testing in a multi-center Collaborative Biomarker Study (CBS) and correlation with clinicopathological features

Background: Accurate determination of HER2 status is critical in determining appropriate therapy for breast cancer patients. The HERmark® assay is a novel method to quantitatively measure HER2 total protein expression (H2T) in breast cancer. In this study, we compared HERmark H2T with central laboratory HER2 retesting and local (site reported) HER2 testing of formalin-fixed, paraffin-embedded (FFPE) breast cancer tissues. The quantitative total HER2 measurements (H2T) by HERmark and results of local HER2 tests were correlated with tumor pathohistological characteristics and overall survival of breast cancer patients.

Methods: 232 FFPE breast cancer tissues were provided by 11 CBS study sites for HER2 testing by the HERmark assay and central laboratory IHC re-testing performed in blinded fashion. Local HER2 immunohistochemistry and/or fluorescence in situ hybridization (FISH) results and valid HERmark H2T and central HER2 IHC results were obtained in 192 cases for analysis.

Results: H2T showed a significant correlation with central HER2 IHC staining intensity (P &lt; 0.0001). The concordance rates of positive and negative HERmark status (excluding equivocal) with those of local HER2 status determined by the CBS sites, and with those of central HER2 IHC status were 84% (Kappa = 0.68) and 96% (Kappa = 0.91), respectively. Higher H2T levels significantly correlated with higher tumor grade (p = 0.007) and negative ER/PR status (p = 0.002). Twenty-six (14%) cases showed discordant (conversion of negative and positive) results between local HER2 status and HERmark status. Of the discordant cases, HERmark significantly agreed with H-score of central HER2 IHC retesting (p = 0.014), as compared with local HER2 status. The concordant negative group (local HER2 negative/H2T low) demonstrated better overall survival (OS) (HR = 0.198, p = 0.0001), compared to that of concordant positive group (local HER2 positive/H2T high). The concordant negative group also showed better OS than that of discordant local HER2 negative/H2T high group (HR = 0.065, p = 0.0003), but showed no significant difference in OS as compared to that of discordant local HER2 positive/H2T low group (HR = 1.774, p = 0.499).). In 24 cases (13%) considered to be “triple negative” by local HER2, ER and PR testing, HERmark re-classified 4 cases (17%) as HER2 positive.

Conclusions: H2T by HERmark yields a continuum of quantitative HER2 protein measurements that shows an excellent correlation with central HER2 IHC retesting and confirms the known correlations between HER2 expression with tumor grade and ER/PR status. OS results of concordant HER2 positive or negative groups (between local HER2 testing and HERmark H2T) confirmed that HER2 positive patients (excluding adjuvant trastuzumab therapy) have worse OS than patients with HER2 negative disease. However, in the HERmark and local HER2 discordant groups, OS appeared to track better with H2T by HERmark and not with the local HER2 status. Novel quantitative HER2 measurements may identify patients with false (+) and (−) HER2 status by local HER2 testing and may provide added clinical value to routine “real world” HER2 testing.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-05-06.

Heterogeneous reactions of HOI, ICl and IBr on sea salt and sea salt proxies

The heterogeneous chemistry of HOI, ICl and IBr on sea salt and sea salt proxies has been studied at 274 K using two experimental approaches: a wetted wall flow tube coupled to an electron impact mass spectrometer (WWFT-MS) and an aerosol flow tube (AFT) coupled to a differential mobility analyser (DMA) and a chemical ionisation mass spectrometer (CIMS). Uptake of all three title molecules into bulk aqueous halide salt films was rapid and controlled by gas phase diffusion. Uptake of HOI gave rise to gas-phase ICl and IBr, with the latter being the predominant product whenever Br(-) was present. Only partial release of IBr was observed due to high solubility of dihalogens in the film. ICl uptake gave the same yield of IBr as HOI uptake. Uptake of ICl on NaBr aerosol was accommodation limited with alpha = 0.018 +/- 0.004 and gas phase IBr product has a yield of 0.6 +/- 0.3. The results show that HOI can act as a catalyst for activation of bromine from sea-salt aerosols in the marine boundary layer, via the reactions: HOI(aq) + Cl + H--> ICl(aq) + H(2)O(l) and ICl(aq) + Br--> IBr(aq) + Cl.

Sulfur polymer solidification/stabilization of elemental mercury waste

Elemental mercury, contaminated with radionuclides, presents a waste disposal problem throughout the Department of Energy complex. In this paper we describe a new process to immobilize elemental mercury wastes, including those contaminated with radionuclides, in a form that is non-dispersible, will meet EPA leaching criteria, and has low mercury vapor pressure. In this stabilization and solidification process, elemental mercury is combined with an excess of powdered sulfur polymer cement (SPC) and sulfide additives in a mixing vessel and heated to approximately 40 degrees C for several hours, until all of the mercury is converted into mercuric sulfide (HgS). Additional SPC is then added and the temperature of the mixture raised to 135 degrees C, resulting in a molten liquid which is poured into a mold where it cools and solidifies. The final treated waste was characterized by powder X-ray diffraction and found to be a mixture of the hexagonal and orthorhombic forms of mercuric sulfide. The Toxicity Characteristic Leaching Procedure was used to assess mercury releases, which for the optimized process averaged 25.8 microg/l, with some samples being well below the new EPA Universal Treatment Standard of 25 microg/l. Longer term leach tests were also conducted, indicating that the leaching process was dominated by diffusion. Values for the effective diffusion coefficient averaged 7.6x10(-18) cm2/s. Concentrations of mercury vapor from treated waste in equilibrium static headspace tests averaged 0.6 mg/m3.

Educational attainments of school leavers with a preschool history of speech-language impairments

This paper reports a follow-up study of a cohort of 16- and 17-year-olds with a preschool history of speech-language impairment and whom Bishop and Edmundson (1987) originally studied. Information collected by questionnaire showed that the GCSE grades of those whose language impairments had resolved by 5;06 were below those of age-matched controls. However, the number of GCSE examinations entered and passed was significantly more than those of the 'persistent S-LI' and 'general delay' groups. Overall, IQ was the strongest predictor of educational attainment. However, even when IQ was controlled, literacy skills accounted for independent variance in achievement, especially among those with a history of language difficulty. The survey also noted that the majority of students across all groups remained in full-time education; however, the adolescents with a background of S-LI were more likely to follow vocational and employment training courses rather than A-levels.

G-proteins in growth and apoptosis: lessons from the heart

The acute contractile function of the heart is controlled by the effects of released nonepinephrine (NE) on cardiac adrenergic receptors. NE can also act in a more chronic fashion to induce cardiomyocyte growth, characterized by cell enlargement (hypertrophy), increased protein synthesis, alterations in gene expression and addition of sarcomeres. These responses enhance cardiomyocyte contractile function and thus allow the heart to compensate for increased stress. The hypertrophic effects of NE are mediated through Gq-coupled alpha(1)-adrenergic receptors and are mimicked by the actions of other neurohormones (endothelin, prostaglandin F(2alpha) angiotensin II) that also act on Gq-coupled receptors. Activation of phospholipase C by Gq is necessary for these responses, and protein kinase C and MAP kinases have also been implicated. Gq stimulated cardiac hypertrophy is also evident in transgenic mouse models. In contrast, stimulation of G(s)-coupled beta-adrenergic receptors or G(i)-coupled receptors do not directly effect cardiomyocyte hypertrophy. Apoptosis is also induced by G-protein-coupled receptor stimulation in cardiomyocytes. Sustained or excessive activation of either Gq- or Gs-signaling pathways results in apoptotic loss of cardiomyocytes both in vitro and in vivo. Apoptosis is associated with decreased ventricular function in the failing heart. Cardiomyocytes provide an ideal model system for understanding the basis for G-protein mediated hypertrophy and apoptosis, and the mechanisms responsible for the transition from compensatory to deleterious levels of signaling. This information may prove critical for designing interventions that prevent the pathophysiological consequences of heart failure.

Cardiomyocyte apoptosis induced by Galphaq signaling is mediated by permeability transition pore formation and activation of the mitochondrial death pathway

Expression of the wild-type alpha subunit of Gq stimulates phospholipase C and induces hypertrophy in cardiomyocytes. Addition of Gq-coupled receptor agonists additionally activates phospholipase C, as does expression of a constitutively active mutant form of Galphaq. Under these conditions, hypertrophy is rapidly succeeded by apoptotic cellular and molecular changes, including myofilament disorganization, loss of mitochondrial membrane potential, alterations in Bcl-2 family protein levels, DNA fragmentation, increased caspase activity ( approximately 4-fold), cytochrome c redistribution, and nuclear chromatin condensation in approximately 12% of the cells. We used various interventions to define the molecular relationships between these events and identify potential sites at which these features of apoptosis could be rescued. Treatment with caspase inhibitors prevented DNA fragmentation and promoted myocyte survival; however, cytochrome c release and loss of mitochondrial membrane potential still occurred. In contrast, treatment with bongkrekic acid, an inhibitor of the mitochondrial permeability transition pore, not only prevented DNA fragmentation and reduced nuclear chromatin condensation but also preserved mitochondrial membrane potential and limited cytochrome c redistribution to only approximately 2% of cells. These data demonstrate the central role of mitochondrial membrane potential in initiation of caspase activation and downstream apoptotic events and suggest that preservation of mitochondrial integrity is crucial for prolonging the life and function of cardiomyocytes exposed to pathological levels of stress.

Hematopoietic response to lineage-non-specific (rrIL-3) and lineage-specific (rhG-CSF, rhEpo, rhTpo) cytokine administration in SIV-infected rhesus macaques is related to stage of infection

The present study reports the hematopoietic response to the exogenous administration of recombinant rhesus interleukin-3 (rrIL-3) or a combination of recombinant human granulocyte colony-stimulating factor (rhG-CSF)/erythropoietin (Epo)/thrombopoietin (Tpo) at two different stages of SIV infection: Early-stage (n = 6, CD4 + > 1000/microl and mild splenomegaly) and late-stage (n = 6, CD4 + < 500/microl, progressive hepatosplenomegaly and/or weight loss). SIV-infected animals exhibited significantly impaired bone marrow (BM) and peripheral blood (PB) responses to both rrIL-3 and rhG-CSF/Epo/Tpo administration, as compared to historic controls. In addition, compared to early-stage SIV-infected animals, late-stage SIV-infected macaques demonstrated a more marked dysfunction, as assessed by PB and BM CD34 + content and clonogenic progenitors (colony-forming unit). Neither rrIL-3 nor rhG-CSF/Epo/Tpo administration during either early-stage or late-stage SIV infection increased the viral load, as assessed by bDNA assay. These data suggest that hematopoietic reserve and the response to various cytokines is decreased even in early-stage SIV infection, with the hematopoietic dysfunction progressing in parallel to SIV infection.

Problems of behaviour, reading and arithmetic: assessments of comorbidity using the Strengths and Difficulties Questionnaire

BACKGROUND

Estimates of academic underachievement among school children vary widely, depending on the geographical location and on the criteria used to define attainment.

AIM

To examine the relationship between behaviour problems and academic attainment in a large UK primary school.

METHOD

A school population (364 children from Years 3 to 6 inclusive) were assessed on a range of cognitive ability tasks. These included standardised tests of reading, arithmetic and verbal and non-verbal intelligence. Under-achievement was assessed using different criteria. To assess behaviour, teachers completed the Strengths and Difficulties Questionnaire (Goodman, 1997) for each participating child. Finally, academic progress of a subset of children was assessed after one year.

RESULTS

Indicated a significant relationship between behaviour and academic attainment; prosocial behaviour was positively correlated with reading and arithmetic, hyperactivity and conduct problems were negatively correlated. This association was especially strong in the children rated by the questionnaire as hyperactive, where around 1 in 5 had a specific reading deficit. However, there was no evidence to indicate that children with behaviour problems made less academic progress over a one-year period relative to their peers.

CONCLUSION

The study highlights the importance of assessing both cognitive skills and behaviour, particularly when planning the educational management of children with reading difficulties.

G alpha-q/11 protein plays a key role in insulin-induced glucose transport in 3T3-L1 adipocytes

We evaluated the role of the G alpha-q (Galphaq) subunit of heterotrimeric G proteins in the insulin signaling pathway leading to GLUT4 translocation. We inhibited endogenous Galphaq function by single cell microinjection of anti-Galphaq/11 antibody or RGS2 protein (a GAP protein for Galphaq), followed by immunostaining to assess GLUT4 translocation in 3T3-L1 adipocytes. Galphaq/11 antibody and RGS2 inhibited insulin-induced GLUT4 translocation by 60 or 75%, respectively, indicating that activated Galphaq is important for insulin-induced glucose transport. We then assessed the effect of overexpressing wild-type Galphaq (WT-Galphaq) or a constitutively active Galphaq mutant (Q209L-Galphaq) by using an adenovirus expression vector. In the basal state, Q209L-Galphaq expression stimulated 2-deoxy-D-glucose uptake and GLUT4 translocation to 70% of the maximal insulin effect. This effect of Q209L-Galphaq was inhibited by wortmannin, suggesting that it is phosphatidylinositol 3-kinase (PI3-kinase) dependent. We further show that Q209L-Galphaq stimulates PI3-kinase activity in p110alpha and p110gamma immunoprecipitates by 3- and 8-fold, respectively, whereas insulin stimulates this activity mostly in p110alpha by 10-fold. Nevertheless, only microinjection of anti-p110alpha (and not p110gamma) antibody inhibited both insulin- and Q209L-Galphaq-induced GLUT4 translocation, suggesting that the metabolic effects induced by Q209L-Galphaq are dependent on the p110alpha subunit of PI3-kinase. In summary, (i) Galphaq appears to play a necessary role in insulin-stimulated glucose transport, (ii) Galphaq action in the insulin signaling pathway is upstream of and dependent upon PI3-kinase, and (iii) Galphaq can transmit signals from the insulin receptor to the p110alpha subunit of PI3-kinase, which leads to GLUT4 translocation.

Recombinant human CD40 ligand inhibits simian immunodeficiency virus replication: a role for interleukin- 16

CD40 ligand (CD40L), expressed on activated T cells, binds its receptor, CD40, on dendritic cells, B cells, and monocytes/ macrophages. Human immunodeficiency virus (HIV)-infected individuals exhibit normal B-cell CD40 expression but diminished expression of CD40L on CD4 + T cells. Thus, we studied recombinant human CD40L (huCD40L) in an in vitro rhesus macaque model of acquired immunodeficiency syndrome (AIDS). huCD40L induced peripheral blood mononuclear cell (PBMC) proliferation independent of mitogenic cytokines and led to a 70% reduction in p27 production by simian immunodeficiency virus (SIV) mac239 infected PBMCs (P < 0.05). Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis showed reduced expression of SIV gag and increased expression of interleukin (IL)-16 mRNA. Supernatants from huCD40L-stimulated PBMC and control cultures contained similar amounts of IL-16, suggesting an intracellular antiviral effect by IL-16. Phytohemagglutinin (PHA)-stimulated PBMCs similarly cultured with huCD40L showed only slight increases in chemokine production (P > 0.05). These results suggest that huCD40L inhibits replication (antigen and mRNA production) of SIVmac239. This response involves huCD40L induction of IL16 mRNA expression and appears to be independent of beta-chemokines.

Working memory deficits in poor comprehenders reflect underlying language impairments

Three experiments assessed memory skills in good and poor comprehenders, matched for decoding skill. Experiments 1 and 2 investigated phonological and semantic contributions to short-term memory by comparing serial recall for words varying in length, lexicality, and concreteness. Poor comprehenders showed normal sensitivity to phonological manipulations (length and lexicality) but, consistent with their semantic weaknesses, their recall of abstract words was poor. Experiment 3 investigated verbal and spatial working memory. While poor comprehenders achieved normal spatial spans, their verbal spans were impaired. These results are discussed within a theoretical framework in which the memory difficulties associated with poor reading comprehension are specific to the verbal domain and are a concomitant of language impairment, rather than a cause of reading comprehension failure.

Molecular cloning and expression of rhesus macaque and sooty mangabey interleukin 16: biologic activity and effect on simian immunodeficiency virus infection and/or replication

Interleukin 16 (IL-16) has been shown to diminish HIV and SIV replication through inhibition of HIV and SIV mRNA transcription. To evaluate its role further, we compared IL-16 cloned from disease-susceptible rhesus macaques and disease-resistant sooty mangabeys. Recombinant rhesus macaque (rr) IL-16 was compared with recombinant sooty mangabey (rm), human, and other nonhuman primate IL-16 sequences and evaluated for its ability to induce chemotaxis and inhibit the mixed lymphocyte response (MLR). Also, rrIL-16 and rmIL-16 were evaluated for suppression of SIVmac251, which replicates efficiently in T cells and monocyte/macrophages (dual tropic), and cloned SIVmac239, which replicates efficiently in T cells (T tropic). Sequence comparison of rrIL-16 and rmIL-16 with human IL-16 showed >97% amino acid identity. Biocharacterization of rrIL-16 revealed potent induction of chemotaxis (p < 0.05) and marked inhibition of MLR (73 +/- 0.6%,p < 0.05) in rhesus and human cell systems. Using rrIL-16 and rmIL-16, p27 antigen production from PBMCs infected with SIVmac251 was decreased up to 70% (p < 0.05 and p < 0.01, respectively). In similar cultures infected with SIVmac239, rrIL-16 and rmIL-16 reduced p27 levels by 96 and 100%, respectively. These data demonstrate the biologic and antiviral functionality of rrIL-16 and rmIL-16.

Enhanced Galphaq signaling: a common pathway mediates cardiac hypertrophy and apoptotic heart failure

Receptor-mediated Gq signaling promotes hypertrophic growth of cultured neonatal rat cardiac myocytes and is postulated to transduce in vivo cardiac pressure overload hypertrophy. Although initially compensatory, hypertrophy can proceed by unknown mechanisms to cardiac failure. We used adenoviral infection and transgenic overexpression of the alpha subunit of Gq to autonomously activate Gq signaling in cardiomyocytes. In cultured cardiac myocytes, overexpression of wild-type Galphaq resulted in hypertrophic growth. Strikingly, expression of a constitutively activated mutant of Galphaq, which further increased Gq signaling, produced initial hypertrophy, which rapidly progressed to apoptotic cardiomyocyte death. This paradigm was recapitulated during pregnancy in Galphaq overexpressing mice and in transgenic mice expressing high levels of wild-type Galphaq. The consequence of cardiomyocyte apoptosis was a transition from compensated hypertrophy to a rapidly progressive and lethal cardiomyopathy. Progression from hypertrophy to apoptosis in vitro and in vivo was coincident with activation of p38 and Jun kinases. These data suggest a mechanism in which moderate levels of Gq signaling stimulate cardiac hypertrophy whereas high level Gq activation results in cardiomyocyte apoptosis. The identification of a single biochemical stimulus regulating cardiomyocyte growth and death suggests a plausible mechanism for the progression of compensated hypertrophy to decompensated heart failure.

Tyrosine kinase and c-Jun NH2-terminal kinase mediate hypertrophic responses to prostaglandin F2alpha in cultured neonatal rat ventricular myocytes

Myocardial infarction results in focal areas of ischemia, hypoxia, necrosis, and decreased contractile function. To compensate for loss of contractile function, remaining viable myocytes undergo hypertrophic growth. Prostaglandin F2alpha (PGF2alpha), which is released from cells of the myocardium during periods of stress such as hypoxia or ischemia/reperfusion, has recently been shown to stimulate hypertrophic growth in neonatal rat ventricular myocytes. In the present study, we determine which growth-related intracellular pathways are required for PGF2alpha to induce morphological and genetic features characteristic of the hypertrophic phenotype. In cardiomyocytes, PGF2alpha increases the hydrolysis of inositol phosphates and induces the translocation of protein kinase C epsilon to the myocyte membrane, consistent with PGF2alpha receptor coupling to Gq. PGF2alpha also activates the extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase pathways. Surprisingly, studies using pharmacological inhibitors and transfection of dominant-interfering proteins demonstrate that PGF2alpha-induced myocyte hypertrophy occurs independent of either PKC, p38, or ERK pathways. Additional studies demonstrate that PGF2alpha stimulates protein tyrosine phosphorylation and activates c-Jun NH2-terminal kinase and suggest that these pathways mediate hypertrophic growth in response to PGF2alpha.

Hematologic and virologic effects of lineage-specific and non-lineage-specific recombinant human and rhesus cytokines in a cohort of SIVmac239-infected macaques

The hematologic abnormalities of SIV and HIV are well described, although the mechanisms that lead to hematopoietic dysfunction are yet to be fully defined. A number of growth factors and cytokines have been used to induce the differentiation, maturation, and proliferation of appropriate lineages, with the aim that such therapy will lead to functional hematopoietic reconstitution. Within this context, some cytokines have been shown to influence HIV and SIV replication in vitro and, in selected cases, in vivo. However, few studies detail the effects of hematopoietic cytokines such as IL-3, Flt-3 ligand, G-CSF, Tpo, and Epo or correlate the effects on virus replication. In an effort to address this issue, we infected 12 rhesus macaques with 500 TCID50 of SIVmac239 and intensively evaluated hematologic, virologic, and immunologic parameters during administration of cytokines. When all animals had lymphadenopathy, hepatosplenomegaly, and CD4+ cell counts > or =1000/microl, subgroups of three rhesus macaques were administered either rhFlt-3; rrIL-3a; combination of rhG-CSF, rhTpo, and rhEpo (rhGET); or rrIL-12. Fourteen days of rhFlt-3 administration induced expansion of the bone marrow CD34+ cells and granulocyte-macrophage colony-forming units (GM-CFUs) and increased absolute peripheral blood CD34+ cells and total CFUs. Following rrIL-3 and rhGET administration absolute peripheral blood CD34+ cells and total CFUs increased. rhGET also increased granulocyte, platelet, and reticulocyte counts by day 14 of administration. Branched DNA and coculture assays did not demonstrate any significant change in viral load with any of the cytokines administered. These data suggest that SIV-infected rhesus macaques have the hematopoietic capability to expand and mobilize CD34+ and GM-CFU progenitors and formed elements at 6-8 months postinfection in response to various cytokines, without increasing viral load.

Expression and in vitro evaluation of rhesus macaque wild type (wt) and modified CC chemokines

Several human CC chemokines have been shown to inhibit HIV/ SIV infection in vitro, providing the rationale for their potential use in vivo. However, because of their inherent physiological effect, such chemokines are reasoned to be of limited therapeutic value due to potential side effects. The knowledge that amino terminus modified or deleted human RANTES retains its receptor binding properties but loses its signaling properties has provided a means to use such modified chemokines in vivo for possible therapeutic benefits. In efforts to test the efficacy of such modified chemokines, our laboratory has cloned, sequenced, and prepared recombinant forms of wild-type (wt) and amino-terminus modified rhesus macaque chemokines MIP-1alpha, MIP-1beta, and RANTES. These sets of chemokines were tested for their potential to inhibit SIV infection and induce signaling. The data showed that whereas wt chemokines retained both virus inhibitory and signaling functions, corresponding amino-terminus modified chemokines only showed virus inhibitory effects without detectable signaling effects. Such reagents will be valuable for evaluation of their therapeutic potential in vivo, either alone or as adjuncts to other chemotherapeutic drugs.

Working memory and children's mental addition

Two experiments investigated the extent to which children's mental arithmetic is constrained by working memory rather than their arithmetical competence. A span procedure was used to measure the limit on English- and German-speaking children's ability to add together pairs of multidigit numbers. The children's ages ranged from 7 years 7 months to 11 years 5 months. Spans for mental addition were higher when the numbers to be added were visible throughout calculation than when they were not, consistent with a working memory constraint. Variation in addition span with children's age and with difficulty of the arithmetical operations approximated to a linear function of the speed of adding integers. A similar speed/span relationship has previously been observed for counting span, an artificial task designed to load working memory by combining separate processing and storage subtasks. We conclude that the natural task of mental addition, which combines processing and storage as intrinsic components, reflects working memory in a similar way. Results were remarkably similar both between cultures and across age groups, consistent with the notion of working memory as a general-purpose resource with dynamics that are indifferent to the detailed nature of operations.

Mechanical stimulation of organogenic cardiomyocyte growth in vitro

Adherent cultures of neonatal rat cardiomyocytes were subjected to progressive, unidirectional lengthening for 2-4 days in serum-containing medium. This mechanical stretch (25% increase in initial length each day) simulates the eccentric mechanical load placed on in vivo heart cells by increases in postnatal blood pressure and volume. The in vitro mechanical stimuli initiated a number of morphological alterations in the confluent cardiomyocyte population which were similar to those occurring during in vivo heart growth. These include cardiomyocyte organization into parallel arrays of rod-shaped cells, increased cardiomyocyte binucleation, and cardiomyocyte hypertrophy by longitudinal cell growth. Stretch stimulated DNA synthesis in the noncardiomyocyte population but not in the cardiomyocytes. Myosin heavy chain (MHC) content increased 62% over 4 days of stretch and included increased accumulation of both fetal beta-MHC and adult alpha-MHC isoforms. This new model of stretch-induced cardiomyocyte hypertrophy may assist in examining some of the complex mechanogenic growth processes that occur in the rapidly enlarging neonatal heart.

Prostaglandin F2 alpha stimulates hypertrophic growth of cultured neonatal rat ventricular myocytes

Prostaglandin F2 alpha (PGF2 alpha) stimulates protein synthesis of skeletal and smooth muscle cells in culture and is elevated in the heart during compensatory growth. We hypothesized that PGF2 alpha stimulates hypertrophic growth of neonatal rat cardiac myocytes. Prostaglandin F2 alpha increased [3H]phenylalanine incorporation by cultured ventricular myocytes in a dose-dependent manner (EC50 = 11 nM), suggesting action through a PGF-specific receptor. Semiquantitative reverse transcriptase polymerase chain reaction revealed that PGF receptor mRNA is expressed in ventricular myocytes > A7R5 vascular smooth muscle cells >> cardiac fibroblast-like cells. The protein content of cardiomyocyte cultures was increased by 10 nM PGF2 alpha and 11 beta-PGF2 alpha but was unchanged by 10 nM PGD2, PGE2, PGF1 alpha, carbaprostacyclin, U-46619, or 12- or 15-hydroxyeicosatrienoic acid. Stimulation of myofibrillar gene expression by PGF2 alpha was demonstrated by Northern and Western blot analysis for myosin light chain-2 (MLC-2) and by transient transfection experiments with MLC-2 luciferase expression plasmids. In addition, myofibrillogenesis was increased by PGF2 alpha as assessed by immunocytochemical staining with MLC-2 antisera. Prostaglandin F2 alpha did not affect myocyte proliferation or [3H]thymidine incorporation, thus myocyte growth occurred by hypertrophy. Proliferative and hypertrophic growth of cardiac fibroblast-like cells were unaffected by PGF2 alpha. We conclude that PFG2 alpha stimulates hypertrophic growth of neonatal rat ventricular myocytes in culture and speculate that PGF2 alpha plays a role in myocardial adaptation to chronic hypertrophic stimuli, recovery from injury, and cardiac ontogeny.

Nitric oxide reduces early growth response-1 gene expression in rat lung macrophages treated with interferon-gamma and lipopolysaccharide

Since early growth response-1 (Egr-1) is required for macrophage differentiation and nitric oxide (NO) is immunosuppressive, we hypothesized that NO would reduce Egr-1 expression in rat lung macrophages. The inflammatory stimuli interferon-gamma and lipopolysaccharide induced an early, transient increase in Egr-1 mRNA (> 5-fold at 2 h) and a sustained, high level of inducible NO synthase mRNA (> 100-fold from 4 to 24 h). The NO metabolites nitrite and nitrate rose > 10-fold in medium from stimulated versus unstimulated cells over 24 h. Concomitant with elevated nitrogen oxides, Egr-1 mRNA levels declined to 80% below unstimulated cells at 24 h. This decline was blocked by an inhibitor of NO production, NG-monomethyl-L-arginine. Further, the NO donor S-nitroso-N-acetylpenicillamine inhibited Egr-1 expression in a dose-dependent manner, producing complete inhibition at 0.5 mM. The effect of S-nitroso-N-acetylpenicillamine was not due to reduced macrophage viability. We conclude that Egr-1 induction precedes inducible NO synthase induction in stimulated rat macrophages and that subsequent NO production reduces macrophage expression of Egr-1. We propose that this mechanism is used to regulate macrophage differentiation in human immunodeficiency virus infection and other inflammatory states.

Treatment of finger dysplasia with metacarpal base defect

The hypoplastic finger with metacarpal base defect is a rare anomaly. Metacarpal lengthening is not a reasonable treatment option because of severe hypoplasia of the metacarpal. Complete amputation with closure of the interdigital space is effective but most parents want to save any digit of their child. We prefer to release the syndactyly and save the finger, with its shortened three phalanges, during childhood. Our parents and patients have been satisfied with the short digit. At a later age the metacarpal of the hypoplastic finger can be fused to one or the other adjacent metacarpals. Alternative methods to increase function and improve appearance are presented.