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Uniparental disomy is a genetic cause of disease that may result in the inheritance of an autosomal recessive condition. A child with developmental delay and hypotonia was seen and found to have severely abnormal myelination. Lysosomal enzyme testing identified an isolated deficiency of beta-galactosidase. Subsequently, homozygous missense mutations in the galactosidase, beta 1 (GLB1) gene on chromosome 3 were found. Parental testing confirmed inheritance of two copies of the same mutated maternal GLB1 gene, and no paternal copy. SNP analysis was also done to confirm paternity. The patient was ultimately diagnosed with autosomal recessive GM1 gangliosidosis caused by maternal uniparental isodisomy. We provide a review of this patient and others in which uniparental disomy (UPD) of a non-imprinted chromosome unexpectedly caused an autosomal recessive condition. This is the first case of GM1 gangliosidosis reported in the literature to have been caused by UPD. It is important for genetic counselors and other health care providers to be aware of the possibility of autosomal recessive disease caused by UPD. UPD as a cause of autosomal recessive disease drastically changes the recurrence risk for families, and discussions surrounding UPD can be complex. Working with families to understand UPD when it occurs requires a secure and trusting counselor-family relationship.

Pol III-related leukodystrophies are caused by mutations in POLR3A and POLR3B genes and all share peculiar imaging and clinical features. The objectives of this study are (1) to define the neuroradiologic pattern in a cohort of POLR3A and POLR3B subjects and (2) to compare the neuroradiologic pattern of Pol III-related leukodystrophies with other hypomyelinating disorders. The magnetic resonance imaging (MRI) examinations of 13 patients with POLR3A and POLR3B mutations and of 14 patients with other hypomyelinating disorders were analyzed. All the subjects with Pol III-related leukodystrophies presented hypomyelination associated with T2 hypointensity of the thalami and/or the pallida. Twelve subjects (92%) presented T2 hypointensity of the optic radiations. Cerebellar atrophy was observed in most patients (92%). The combination of the analyzed criteria identified patients with Pol III-related leukodystrophies with a sensitivity of 84.6% and a specificity of 92.9%.

Background: More than half of patients with genetic leukoencephalopathies remain without a specific diagnosis; this is particularly true in individuals with a likely primary neuronal etiology, such as those in which abnormal white matter occurs in combination with severe epilepsy., Patient: A child with a severe early infantile epileptic encephalopathy and abnormal myelination underwent whole exome sequencing., Results: Whole exome sequencing identified a heterozygous de novo mutation in KCNT1, a sodium-gated potassium channel gene., Conclusions: Severely delayed myelination was anecdotally reported in previous patients with KCNT1 mutations. This case reinforces that KCNT1 sequencing should be included in an investigation of patients with severely delayed myelination and epilepsy., (Published by Elsevier Inc.)

Background: Aicardi-Goutières syndrome (AGS) is an inflammatory disorder caused by mutations in any of six genes (TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, and ADAR). The disease is severe and effective treatments are urgently needed. We investigated the status of interferon-related biomarkers in patients with AGS with a view to future use in diagnosis and clinical trials., Methods: In this case-control study, samples were collected prospectively from patients with mutation-proven AGS. The expression of six interferon-stimulated genes (ISGs) was measured by quantitative PCR, and the median fold change, when compared with the median of healthy controls, was used to create an interferon score for each patient. Scores higher than the mean of controls plus two SD (>2·466) were designated as positive. Additionally, we collated historical data for interferon activity, measured with a viral cytopathic assay, in CSF and serum from mutation-positive patients with AGS. We also undertook neutralisation assays of interferon activity in serum, and looked for the presence of autoantibodies against a panel of interferon proteins., Findings: 74 (90%) of 82 patients had a positive interferon score (median 12·90, IQR 6·14-20·41) compared with two (7%) of 29 controls (median 0·93, IQR 0·57-1·30). Of the eight patients with a negative interferon score, seven had mutations in RNASEH2B (seven [27%] of all 26 patients with mutations in this gene). Repeat sampling in 16 patients was consistent for the presence or absence of an interferon signature on 39 of 41 occasions. Interferon activity (tested in 147 patients) was negatively correlated with age (CSF, r=-0·604; serum, r=-0·289), and was higher in CSF than in serum in 104 of 136 paired samples. Neutralisation assays suggested that measurable antiviral activity was related to interferon α production. We did not record significantly increased concentrations of autoantibodies to interferon subtypes in patients with AGS, or an association between the presence of autoantibodies and interferon score or serum interferon activity., Interpretation: AGS is consistently associated with an interferon signature, which is apparently sustained over time and can thus be used to differentiate patients with AGS from controls. If future studies show that interferon status is a reactive biomarker, the measurement of an interferon score might prove useful in the assessment of treatment efficacy in clinical trials., Funding: European Union's Seventh Framework Programme; European Research Council., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Objectives/hypothesis: To develop and validate a cough severity index (CSI) which quantifies patients' symptoms associated with upper airway chronic cough and to provide a tool for treatment outcome measures., Methods: Two hundred patients who had a complaint of chronic cough and/or dyspnea were given a 49- item questionnaire developed through a clinical consensus of the most common symptoms of chronic cough of upper airway origin. The instrument was reduced to 10 questions using statistical methodology. Fifty subsequent patients were given the CSI to measure test-retest reliability at two different moments in time. Twenty healthy controls (HC) were given the instrument to obtain validity. An additional 95 participants provided pre- and posttreatment outcomes using the CSI., Results: Principle Component Analysis (PCA) revealed a single factor with the original 49 questions. A combination of PCA, rank-ordering item-total correlation and communality, as well as clinical consensus further reduced the questionnaire to 10 items. Internal consistency of the CSI was 0.97. Test-retest reliability was r = 0.83. An r = 0.60 for divergent validity between the CSI and the Cough-Specific Quality-of-Life Questionnaire (CQLQ) demonstrated two fairly separate instruments, although both measured cough. Mann-Whitney test was significant between symptomatic patients and healthy controls (P < 0.0004). The results of 20 HC showed a mean of 0.45 (standard deviation = 1.39). Results for treatment outcomes revealed significance with the Wilcoxon test (P < 0.0001) and paired samples t test showed significantly different correlations between pre- and postmeasures., Conclusion: The CSI is a short, simple instrument that can be used in the clinical setting to quantify a patient's symptoms of chronic cough of upper airway origin. It represents a statistically reliable, valid, and clinically relevant instrument that can be used to measure treatment outcomes for chronic cough., (© 2012 The American Laryngological, Rhinological and Otological Society, Inc.)

Monocarboxylate transporter 8 (MCT8) deficiency is an X-linked disorder resulting from an impairment of the transcellular transportation of thyroid hormones. Within the central nervous system thyroid hormone transport is normally mediated by MCT8. Patients are described as affected by a static or slowly progressive clinical picture which consists of variable degrees of mental retardation, hypotonia, spasticity, ataxia and involuntary movements, occasionally paroxysmal. The authors describe the clinical and neuroradiological picture of 3 males patients with marked delayed brain myelination and in which the clinical picture was dominated by early onset nonparoxysmal extrapyramidal symptoms. In one subject a novel mutation is described.

Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a rare hereditary leukoencephalopathy that was originally identified by MRI pattern analysis, and it has thus far defied all attempts at identifying the causal mutation. Only 22 cases are published in the literature to date. We performed exome sequencing on five family trios, two family quartets, and three single probands, which revealed that all eleven H-ABC-diagnosed individuals carry the same de novo single-nucleotide TUBB4A mutation resulting in nonsynonymous change p.Asp249Asn. Detailed investigation of one of the family quartets with the singular finding of an H-ABC-affected sibling pair revealed maternal mosaicism for the mutation, suggesting that rare de novo mutations that are initially phenotypically neutral in a mosaic individual can be disease causing in the subsequent generation. Modeling of TUBB4A shows that the mutation creates a nonsynonymous change at a highly conserved asparagine that sits at the intradimer interface of α-tubulin and β-tubulin, and this change might affect tubulin dimerization, microtubule polymerization, or microtubule stability. Consistent with H-ABC's clinical presentation, TUBB4A is highly expressed in neurons, and a recent report has shown that an N-terminal alteration is associated with a heritable dystonia. Together, these data demonstrate that a single de novo mutation in TUBB4A results in H-ABC., (Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Objective: This study explores a large panel of cytokines in plasma and CSF of patients with Aicardi-Goutières syndrome (AGS) at different ages, in order to establish signatures of cytokines most predictive of AGS., Methods: Plasma from 22 subjects with known mutations were assayed for cytokines using the Milliplex MAP Immunobead system, and compared to results from 8 age-matched normal controls. CSF of 11 additional patients with mutation-proven AGS was tested in an identical manner and compared to results from age-matched controls. Samples were banked and analysis was carried out retrospectively., Results: Significant elevations were seen in FMS-related tyrosine kinase 3 ligand, IP-10, interleukin (IL)-12p40, IL-15, tumor necrosis factor α, and soluble IL 2 receptor α in both AGS patient plasma and CSF relative to controls. Additionally, this cytokine signature was able to correctly cluster 9 of 11 AGS cases based on CSF values. While most cytokines decreased exponentially with age, a subgroup including IP-10 demonstrated persistent elevation beyond early childhood., Conclusion: Patients with AGS exhibit plasma and CSF elevations of proinflammatory cytokines. Selected cytokines remain persistently elevated beyond the initial disease phase. This panel of proinflammatory cytokines may be considered for use as diagnostic and therapeutic markers of disease, and may permit improved understanding of disease pathogenesis.

Voice therapy changes how people use and care for their voices. Speech-language pathologists (SLPs) have a multitude of choices from which to modify patient's vocal behaviors. Six SLPs performed 1461 voice therapy sessions and quantified the percentage of time spent in eight component parts of indirect and four component parts of direct voice therapy across five common voice disorders. Voice therapy data collection forms were prospectively completed immediately following each therapy visit. The SLPs were free to choose the component parts of voice therapy best suited for their respective patients. Results showed that direct voice therapy represented more than 75% of the treatment time across all voice therapy sessions. In the components of direct voice therapy, there was no statistical difference between percentages of time spent in resonant voice and flow phonation across all voice disorders. However, a significant difference was found for the time spent addressing transfer to conversational speech for muscle tension dysphonia, lesions, and scar than for vocal immobility and atrophy. Interestingly, while SLPs used a more common approach to direct voice therapy across voice disorders, they tended to vary the use of indirect components of therapy across voice disorders with certain components being addressed in greater length for specific voice disorders. Collectively, these results indicate that although SLPs may individualize their approach to indirect voice therapy, when it comes to direct voice therapy, SLPs have a common approach to voice therapy regardless of voice disorder., (Copyright © 2013 The Voice Foundation. Published by Mosby, Inc. All rights reserved.)

Objective : Reconstructive surgery to improve psychological well-being is commonly offered to children with craniofacial conditions. Few studies have explored the challenges of reconstructive surgery beyond the physical risks: poor treatment outcomes, infection, brain damage, and death. This qualitative study aims to understand the psychological and social implications such interventions can have for individuals with craniofacial conditions. Design : A total of 38 individuals between the ages of 12 and 61 with such craniofacial conditions as Sturge-Weber syndrome, Treacher Collins syndrome, Möbius syndrome, cleft lip and palate, Noonan syndrome, Crouzon syndrome, and amniotic band syndrome participated in semistructured video-recorded interviews. Participants were recruited at conferences, through study flyers, and by word of mouth. Descriptive, thematic analysis was used to identify themes related to reconstructive surgery. Results : Dominant themes included undergoing surgery to reduce stigmatization, the psychological and social implications of the interventions, outcome satisfaction, parental involvement in decision making about surgery, and recommendations for parents considering surgery for their children with craniofacial conditions. Experiences with reconstructive surgery varied, with some participants expressing surgical benefits and others, disillusionment. Conclusions : The range of participant attitudes and experiences reflect the complexity of reconstructive surgery. Pediatric health care teams involved in the care of children with craniofacial conditions play an important role in advising patients (and their parents) about existing treatment options. The psychological and social implications of reconstructive surgery should be relayed to help families weigh the risks and benefits of surgery in an informed and meaningful way.

Integration of genetic and genomic information into the clinical practice of child neurologists is revolutionizing how diagnosis, prognosis, and treatment of neurogenetic diseases are approached. Genetic testing technology, informatics, and interpretation are rapidly expanding. High-throughput next-generation sequencing has changed the landscape of many fields of medicine by enabling new diagnoses and gene/disease associations. Now more than ever, a comprehensive understanding of the risks, benefits, limitations, and nuances of testing in the pediatric population is essential for the child neurologist., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Epidemiologic frequencies of pediatric white matter disorders as a class have not been well defined. This is particularly true of genetic disorders of the white matter of the brain. In this study, ICD-9 codes were used to estimate relative incidence rates and descriptive statistics of leukodystrophies, other genetic leukoencephalopathies and acquired demyelinating disease among children residing in the Washington, D.C. metropolitan area. Children being treated at US children's hospitals between January 1, 2004, and December 31, 2009, for acquired demyelinating disease or genetic white matter disorders were captured using the Pediatric Health Information System and the Physician Practice Management system and validated with local electronic medical records. Comparisons were made between genetic white matter disorders and acquired demyelinating disorders, to determine differences in incidence, age, gender, ethnicity, and mortality. Genetic causes of white matter disease identified with ICD-9 codes had an estimated incidence of 1.2/100,000 children in the Washington, DC area. What was of interest was nearly 5 out of 10 cases of pediatric white matter disease of any etiology were attributable to genetic causes. When only progressive white matter diseases were considered, 7 out of 10 cases were attributable to genetic causes, and only 3 out of 10 to progressive acquired demyelinating disease such as multiple sclerosis. These findings signify the important contribution of heritable white matter disorders to pediatric neurologic disease in the Washington, DC, metro area as well as throughout the United States. Continued research of these understudied disorders should compare disease incidence and determinants to validate these findings in different populations., (Published by Elsevier Inc.)

Adenosine deaminases acting on RNA (ADARs) catalyze the hydrolytic deamination of adenosine to inosine in double-stranded RNA (dsRNA) and thereby potentially alter the information content and structure of cellular RNAs. Notably, although the overwhelming majority of such editing events occur in transcripts derived from Alu repeat elements, the biological function of non-coding RNA editing remains uncertain. Here, we show that mutations in ADAR1 (also known as ADAR) cause the autoimmune disorder Aicardi-Goutières syndrome (AGS). As in Adar1-null mice, the human disease state is associated with upregulation of interferon-stimulated genes, indicating a possible role for ADAR1 as a suppressor of type I interferon signaling. Considering recent insights derived from the study of other AGS-related proteins, we speculate that ADAR1 may limit the cytoplasmic accumulation of the dsRNA generated from genomic repetitive elements.

Aim: To elucidate the signaling mechanisms involved in the protective effect of EUK-207 against irradiation-induced cellular damage and apoptosis in human intestinal microvasculature endothelial cells (HIMEC)., Methods: HIMECs were irradiated and treated with EUK-207. Using hydroethidine and DCF-DA fluorescent probe the intracellular superoxide and reactive oxygen species (ROS) were determined. By real-time PCR and western blotting caspase-3, Bcl2 and Bax genes and proteins were analyzed. Proliferation was determined by [(3)H]-thymidine uptake. Immunofluorescence staining was used for translocation of p65 NFκB subunit., Key Finding: Irradiation increased ROS production, apoptosis, Bax, Caspase3 and NFkB activity in HIMEC and inhibited cell survival/growth/proliferation. EUK-207 restored the endothelial functions, markedly inhibited the ROS, up-regulated the Bcl2 and down-regulated Bax and prevented NFκB caspase 3 activity in HIMEC., Significance: HIMEC provide a novel model to define the effect of irradiation induced endothelial dysfunction. Our findings suggest that EUK-207 effectively inhibits the damaging effect of irradiation., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objective: To report the detection of secondary neurotransmitter abnormalities in a group of SPG11 patients and describe treatment with l-dopa/carbidopa and sapropterin., Design: Case reports., Setting: National Institutes of Health in the Undiagnosed Disease Program; Children's National Medical Center in the Myelin Disorders Bioregistry Program., Patients: Four SPG11 patients with a clinical picture of progressive spastic paraparesis complicated by extrapyramidal symptoms and maculopathy., Interventions: L-Dopa/carbidopa and sapropterin., Results: 3/4 patients presented secondary neurotransmitter abnormalities; 4/4 partially responded to L-dopa as well as sapropterin., Conclusions: In the SPG11 patient with extrapyramidal symptoms, a trial of L-dopa/carbidopa and sapropterin and/or evaluation of cerebrospinal fluid neurotransmitters should be considered., (Copyright © 2012 Elsevier Inc. All rights reserved.)

A large number of studies have demonstrated that the nucleus accumbens (NAC) is a critical site in the neuronal circuits controlling reward responses, motivation, and mood, but the neuronal cell type(s) underlying these processes are not yet known. Identification of the neuronal cell types that regulate depression-like states will guide us in understanding the biological basis of mood and its regulation by diseases like major depressive disorder. Taking advantage of recent findings demonstrating that the serotonin receptor chaperone, p11, is an important molecular regulator of depression-like states, here we identify cholinergic interneurons (CINs) as a primary site of action for p11 in the NAC. Depression-like behavior is observed in mice after decrease of p11 levels in NAC CINs. This phenotype is recapitulated by silencing neuronal transmission in these cells, demonstrating that accumbal cholinergic neuronal activity regulates depression-like behaviors and suggesting that accumbal CIN activity is crucial for the regulation of mood and motivation.

Our understanding of current treatments for depression, and the development of more specific therapies, is limited by the complexity of the circuits controlling mood and the distributed actions of antidepressants. Although the therapeutic efficacy of serotonin-specific reuptake inhibitors (SSRIs) is correlated with increases in cortical activity, the cell types crucial for their action remain unknown. Here we employ bacTRAP translational profiling to show that layer 5 corticostriatal pyramidal cells expressing p11 (S100a10) are strongly and specifically responsive to chronic antidepressant treatment. This response requires p11 and includes the specific induction of Htr4 expression. Cortex-specific deletion of p11 abolishes behavioral responses to SSRIs, but does not lead to increased depression-like behaviors. Our data identify corticostriatal projection neurons as critical for the response to antidepressants, and suggest that the regulation of serotonergic tone in this single cell type plays a pivotal role in antidepressant therapy., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to explore anecdotal evidence for an increase in the prevalence of autoimmune diseases in family members of patients with Aicardi-Goutières syndrome (AGS)., Methods: Pedigrees of patients and controls were analyzed using chi-square and logistic regression to assess differences in reports of autoimmune disease among family members of cases and controls. Data was collected at Children's National Medical Center in Washington, DC, USA and at the International Aicardi-Goutières Syndrome Association Scientific Headquarters, C. Mondino National Institute of Neurology in Pavia, Italy., Results: The number of individuals with reported autoimmune disease is significantly related to having a family member with AGS (χ(2) = 6.25, P = 0.01); 10% (35/320) of relatives of patients with AGS had a reported autoimmune disease diagnosis compared to 5% (18/344) of relatives of controls. There was a greater percent of maternal relatives of patients with AGS reporting autoimmune disease (14.6%), compared to controls (6.8%), with the association being statistically significant. The association was not significant for paternal relatives., Conclusion: The prevalence of autoimmune disease in relatives of children with AGS is significantly increased compared to controls. More research is needed to better understand this association.

Purpose: Newborn screening leads to improved treatment and disease outcomes, but false-positive newborn screening results may cause distress for parents. The purpose of this study was to describe the experiences of families who receive a false-positive newborn screening result in an attempt to discover ways to help improve the newborn screening communication process for families., Methods: This was a qualitative study using two methods of data collection: in-depth, semistructured interviews and focus groups. Participants (N = 27) were parents whose children (ages 6-16 months) underwent follow-up testing after newborn screening and whose follow-up test results indicated that the newborn screening result was a false-positive., Results: Our analysis found that parents who have a false-positive newborn screening result experience five distinct stages. Most parents did not report long-term negative impacts of the experience, but some experienced some residual worry. Participants described effective provider communication as key in mitigating stress. Some parents identified the experience as leading to positive outcomes., Conclusion: Identifying best practices for communication between the health care providers and parents is an essential component in improving the newborn screening process. Further research is needed to discover best practices for communication to minimize potential harm and maximize the benefits of newborn screening.

Previous study of the ear ossicles in Primates has demonstrated that they vary on both functional and phylogenetic bases. Such studies have generally employed two-dimensional linear measurements rather than three-dimensional data. The availability of Ultra- high-resolution X-ray computed tomography (UhrCT) has made it possible to accurately image the ossicles so that broadly accepted methodologies for acquiring and studying morphometric data can be applied. Using UhrCT data also allows for the ossicular chain to be studied in anatomical position, so that it is possible to consider the spatial and size relationships of all three bones. One issue impeding the morphometric study of the ear ossicles is a lack of broadly recognized landmarks. Distinguishing landmarks on the ossicles is difficult in part because there are only two areas of articulation in the ossicular chain, one of which (the malleus/incus articulation) has a complex three-dimensional form. A measurement error study is presented demonstrating that a suite of 16 landmarks can be precisely located on reconstructions of the ossicles from UhrCT data. Estimates of measurement error showed that most landmarks were highly replicable, with an average CV for associated interlandmark distances of less than 3%. The positions of these landmarks are chosen to reflect not only the overall shape of the bones in the chain and their relative positions, but also functional parameters. This study should provide a basis for further examination of the smallest bones in the body in three dimensions., (Copyright © 2011 Wiley-Liss, Inc.)

Antiinflammatory drugs achieve their therapeutic actions at least in part by regulation of cytokine formation. A "cytokine hypothesis" of depression is supported by the observation that depressed individuals have elevated plasma levels of certain cytokines compared with healthy controls. Here we investigated a possible interaction between antidepressant agents and antiinflammatory agents on antidepressant-induced behaviors and on p11, a biochemical marker of depressive-like states and antidepressant responses. We found that widely used antiinflammatory drugs antagonize both biochemical and behavioral responses to selective serotonin reuptake inhibitors (SSRIs). In contrast to the levels detected in serum, we found that frontal cortical levels of certain cytokines (e.g., TNFα and IFNγ) were increased by serotonergic antidepressants and that these effects were inhibited by antiinflammatory agents. The antagonistic effect of antiinflammatory agents on antidepressant-induced behaviors was confirmed by analysis of a dataset from a large-scale real-world human study, "sequenced treatment alternatives to relieve depression" (STAR*D), underscoring the clinical significance of our findings. Our data indicate that clinicians should carefully balance the therapeutic benefits of antiinflammatory agents versus the potentially negative consequences of antagonizing the therapeutic efficacy of antidepressant agents in patients suffering from depression.

Background: The protein p11 (also called S100A10) is downregulated in human and rodent depressive-like states. Considerable experimental evidence also implicates p11 in the mechanism of action of antidepressant drugs and electroconvulsive seizures, in part due to its interaction with specific serotonin receptors. Brain-derived neurotrophic factor (BDNF) has been linked to the therapeutic activity of antidepressants in rodent models and humans. In the current study, we investigated whether BDNF regulates p11 in vitro and in vivo., Methods: We utilized primary neuronal cultures, in vivo analyses of transgenic mice, and behavioral techniques to assess the effects of BDNF on p11., Results: Results indicate that BDNF stimulates p11 expression through tropomyosin-related kinase B (trkB) receptors and via the mitogen-activated protein kinase signaling pathway. Brain-derived neurotrophic factor-induced changes in p11 in vivo correlate with changes in ligand binding to the 5-hydroxytryptamine receptor 1B, the subcellular localization of which is known to be regulated by p11. Behavioral studies demonstrate that p11 knockout mice are insensitive to the antidepressant actions of BDNF., Conclusions: Taken together, our data demonstrate that p11 levels are regulated by BDNF in vitro and in vivo and that the antidepressant-like effect of BDNF in two well-established behavioral models requires p11. These data support a role for p11 in the antidepressant activity of neurotrophins., (2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Dopamine neurotransmission controls motor and perseverative behavior, is mediated by protein phosphorylation, and may be perturbed in disorders of attention and hyperactivity. To assess the role of casein kinase I (CK1) in the regulation of dopamine signaling, we generated a genetically modified mouse line that overexpresses CK1delta (CK1delta OE) specifically in the forebrain. Overexpression was confirmed both at the mRNA and at the protein levels. Under basal conditions, CK1delta OE mice exhibited horizontal and vertical hyperactivity, reduced anxiety, and nesting behavior deficiencies. The CK1delta OE mice also presented paradoxical responses to dopamine receptor stimulation, showing hypoactivity following injection of d-amphetamine or methylphenidate, indicating that CK1 activity has a profound effect on dopamine signaling in vivo. Interestingly, CK1delta overexpression led to significantly reduced D1R and D2R dopamine receptor levels. All together, under basal conditions and in response to drug stimulation, the behavioral phenotype of CK1delta OE mice is reminiscent of the symptoms and drug responses observed in attention-deficit/hyperactivity disorder and therefore the CK1delta OE mice appear to be a model for this disorder.

Background: Although it has been postulated for many years that depression is associated with loss of synapses, primarily in the hippocampus, and that antidepressants facilitate synapse growth, we still lack ultrastructural evidence that changes in depressive behavior are indeed correlated with structural synaptic modifications., Methods: We analyzed hippocampal spine synapses of male rats (n=127) with electron microscopic stereology in association with performance in the learned helplessness paradigm., Results: Inescapable footshock (IES) caused an acute and persistent loss of spine synapses in each of CA1, CA3, and dentate gyrus, which was associated with a severe escape deficit in learned helplessness. On the other hand, IES elicited no significant synaptic alterations in motor cortex. A single injection of corticosterone reproduced both the hippocampal synaptic changes and the behavioral responses induced by IES. Treatment of IES-exposed animals for 6 days with desipramine reversed both the hippocampal spine synapse loss and the escape deficit in learned helplessness. We noted, however, that desipramine failed to restore the number of CA1 spine synapses to nonstressed levels, which was associated with a minor escape deficit compared with nonstressed control rats. Shorter, 1-day or 3-day desipramine treatments, however, had neither synaptic nor behavioral effects., Conclusions: These results indicate that changes in depressive behavior are associated with remarkable remodeling of hippocampal spine synapses at the ultrastructural level. Because spine synapse loss contributes to hippocampal dysfunction, this cellular mechanism may be an important component in the neurobiology of stress-related disorders such as depression.

p11 (S100A10), a member of a large family of S100 proteins, interacts with serotonin receptor 1B (5-HTR1B), modulates 5-HT1B receptor signal transduction, and is required for antidepressant responses to activation of this receptor. In the current study, we investigated the specificity of the interaction between 5-HTR1B and p11 by screening brain-expressed S100 proteins against serotonin and noradrenergic receptors. The data indicate that p11 is unique among its family members for its interactions with defined serotonin receptors. We identify a novel p11-interacting receptor (5-HTR4) and characterize the interaction between p11 and 5-HTR4, demonstrating that (1) p11 and 5-HTR4 mRNA and protein are coexpressed in brain regions that are relevant for major depression, (2) p11 increases 5-HTR4 surface expression and facilitates 5-HTR4 signaling, and (3) p11 is required for the behavioral antidepressant responses to 5-HTR4 stimulation in vivo. The essential role played by p11 in modulating signaling through 5-HT4 as well as 5-HT1B receptors supports the concept that this protein may be a key determinant of vulnerability to depression.

Background: Apart from several subjective criteria, ASCUS and LSIL are defined by nuclear enlargement of 2.5x to 3x and > or = 3x the area of a normal intermediate squamous cell nucleus, respectively. The aim of this study was to assess the ability of observers with various degrees of experience to estimate nuclear area ratios., Methods: Forty-five participants (5 anatomic pathologists, 5 cytopathologists, 2 cytopathology fellows, 16 pathology residents, 8 cytotechnologists, 6 medical students, and 3 cytopreparatory staff members) judged the area ratios of pairs of squamous cell nuclei imaged at x100 objective magnification. For Test 1 (T1), participants chose between 5 preset area ratios (1.0x to 1.4x, 1.5x to 1.9x, 2.0x to 2.4x, 2.5x to 2.9x, 3.0x to 3.4x) for 15 pairs of cells with ratios falling in the middle of these intervals. One week after T1, an instructional tutorial was given and T1 was repeated in different order of cell pairs as Test 2 (T2)., Results: The kappa values for all participants were 0.30 for T1 and 0.39 for T2. Accurate responses were given in 50.5% in T1 and 53.5% in T2. Both T1 and T2 responses failed to differentiate between area ratios corresponding to ASCUS and LSIL. There were no differences in accuracy according to sex, experience, or expertise in cytopathology., Conclusions: The overall accuracy of participants in estimating nuclear area ratios was low, especially for ratios in the range of ASCUS versus LSIL, with only minimal improvement after an instructional tutorial. Nuclear area ratio estimation may, therefore, contribute to the well-known substantial variability in ASCUS rates and ASC/squamous intraepithelial lesion ratios., ((c) 2008 American Cancer Society.)

All classes of antidepressants increase hippocampal cell proliferation and neurogenesis, which contributes, in part, to the behavioral actions of these treatments. Among antidepressant treatments, electroconvulsive seizure (ECS) is the most robust stimulator of hippocampal cell proliferation and the most efficacious treatment for depression, but the cellular mechanisms underlying the actions of ECS are unknown. To address this question, we investigated the effect of ECS on proliferation of neural stem-like and/or progenitor cells in the subgranular zone of rat dentate gyrus. We define the neural differentiation cascade from stem-like cells to early neural progenitors (also referred to as quiescent and amplifying neural progenitors, respectively) by coexpression of selective cellular and mitotic activity markers. We find that at an early mitotic phase ECS increases the proliferation of quiescent progenitors and then at a later phase increases the proliferation of amplifying progenitors. We further demonstrate that vascular endothelial growth factor (VEGF) signaling is necessary for ECS induction of quiescent neural progenitor cell proliferation and is sufficient to produce this effect. These findings demonstrate that ECS and subsequent induction of VEGF stimulates the proliferation of neural stem-like cells and neural progenitor cells, thereby accounting for the superior neurogenic actions of ECS compared with chemical antidepressants.

This study was to present an odor provocation/challenge test for laryngeal hypersensitivity in a suspected odor induced dysphonic patient. The second aim was to rule out secondary gain from organic laryngeal hypersensitivity. Two steps were taken for this purpose. First, because the evaluation of hypersensitivity may be affected by the perception of odor, the study investigated laryngeal hypersensitivity during nasal and oral breathing separately to disentangle possible cognitive reactions to odors. Second, a healthy control (HC) participant was used with the identical testing protocol for nasal breathing to minimize unbiased results. The HC's response to nasal breathing of the odors showed no response to all the stimuli. The participant with possible secondary gain issues responded differently to the odors when presented nasally versus orally. Oral breathing showed less severe and less frequent laryngeal hypersensitive reactions. This suggests that laryngeal hypersensitivity was either due to the odor, cognitive information, sensory changes in olfaction leading to psychological conditioning, or for any possible secondary gain. Hence, it is difficult to indicate the precise reason (cause and effect) for the participant's laryngeal hypersensitivity; however, this study describes the first structured, controlled, repeatable, and randomized design to investigate odor induced laryngeal hypersensitivity and decipher possible secondary gain from true laryngeal hypersensitivity.

Ongoing neurogenesis in the adult hippocampus is thought to play a role in learning and memory processes, and in response to antidepressant treatments. Low doses of irradiation (IRR) produce a significant long-lasting inhibitory effect on hippocampal neurogenesis that correlates with long-lasting behavioral deficits. Here we report that electroconvulsive seizure (ECS), which robustly increases adult neurogenesis in naïve animals, also reverses the disruption of neurogenesis produced by IRR exposure. Moreover, we find that vascular endothelial growth factor (VEGF) is an essential mediator of this effect. Expression of VEGF in the granule cell layer (GCL) of the hippocampus is decreased by IRR, and ECS administration reverses this deficit in VEGF. There is a corresponding alteration in the number of endothelial cells, which express VEGF, in the hippocampal GCL following IRR and ECS. We also find that blockade of VEGF signaling attenuates ECS-induced proliferation, and VEGF infusion partially restores proliferation in irradiated animals. To examine the functional consequences of IRR and ECS on neurogenesis, hippocampus-dependent contextual fear conditioning was assessed. We found that following disruption by IRR, ECS restores contextual learning to baseline levels at time points consistent with its effects on neurogenesis. These findings demonstrate that ECS, in part via induction of VEGF, can reverse long-term neurogenesis deficits resulting from IRR, and that these effects have functional consequences on hippocampus-dependent fear memory.

Antidepressants are among the most widely prescribed drugs, however the mechanism underlying their therapeutic efficacy is not known. Neurotrophic factors represent a promising class of targets for antidepressant treatments. We recently characterized a role for vascular endothelial growth factor (VEGF) in cellular and behavioral antidepressant responses. VEGF is a potent mitogen and survival factor for endothelial cells (ECs) and neurons, and modulator of synaptic transmission. Because VEGF has been implicated in a variety of diseases, understanding the molecular and cellular specificity of antidepressant-induced VEGF will be crucial to determine its potential as a therapeutic target in depression.

The respiratory tract is a major mucosal site for microorganism entry into the body, and type I interferon (IFN) and dendritic cells constitute a first line of defense against viral infections. We have analyzed the interaction between a model DNA virus, plasmacytoid dendritic cells, and type I IFN during lung infection of mice. Our data show that murine gammaherpesvirus 68 (gammaHV68) inhibits type I IFN secretion by dendritic cells and that plasmacytoid dendritic cells are necessary for conventional dendritic cell maturation in response to gammaHV68. Following gammaHV68 intranasal inoculation, the local and systemic IFN-alpha/beta response is below detectable levels, and plasmacytoid dendritic cells are activated and recruited into the lung with a tissue distribution that differs from that of conventional dendritic cells. Our results suggest that plasmacytoid dendritic cells and type I IFN have important but independent roles during the early response to a respiratory gammaHV68 infection. gammaHV68 infection inhibits type I IFN production by dendritic cells and is a poor inducer of IFN-alpha/beta in vivo, which may serve as an immune evasion strategy.

During infection with viruses that establish latency, the immune system needs to maintain lifelong control of the infectious agent in the presence of persistent Ag. By using a gamma-herpesvirus (gammaHV) infection model, we demonstrate that a small number of virus-specific central-memory CD8+ T cells develop early during infection, and that virus-specific CD8+T cells maintain functional and protective capacities during chronic infection despite low-level Ag persistence. During the primary immune response, we show generation of CD8+ memory T cell precursors expressing lymphoid homing molecules (CCR7, L-selectin) and homeostatic cytokine receptors (IL-7alpha, IL-2/IL-15beta). During long-term persistent infection, central-memory cells constitute 20-50% of the virus-specific CD8+ T cell population and maintain the expression of L-selectin, CCR7, and IL-7R molecules. Functional analyses demonstrate that during viral persistence: 1) CD8+ T cells maintain TCR affinity for peptide/MHC complexes, 2) the functional avidity of CD8+ T cells measured as the capacity to produce IFN-gamma is preserved intact, and 3) virus-specific CD8+ T cells have in vivo killing capacity. Next, we demonstrate that at 8 mo post-virus inoculation, long-term CD8+ T cells are capable of mediating a protective recall response against the establishment of gammaHV68 splenic latency. These observations provide evidence that functional CD8+ memory T cells can be generated and maintained during low-load gammaHV68 persistence.

The neural mechanisms underlying the cellular and behavioral responses to antidepressants are not yet known. Up-regulation of growth factors and adult neurogenesis suggest a role for one or more of these factors in the action of antidepressants. One candidate of interest is vascular endothelial growth factor (VEGF), which was initially characterized for its role in angiogenesis, but also exerts direct mitogenic effects on neural progenitors in vitro. Results of this study demonstrate that VEGF is induced by multiple classes of antidepressants at time points consistent with the induction of cell proliferation and therapeutic action of these treatments. We find that VEGF signaling through the Flk-1 receptor is required for antidepressant-induced cell proliferation. We also show that VEGF-Flk-1 signaling is required and sufficient for behavioral responses in two chronic and two subchronic antidepressant models. Taken together, these studies identify VEGF and VEGF-Flk-1 signaling as mediators of antidepressant actions and potential targets for therapeutic intervention.

The hippocampus is one of several limbic brain structures implicated in the pathophysiology and treatment of mood disorders. Preclinical and clinical studies demonstrate that stress and depression lead to reductions of the total volume of this structure and atrophy and loss of neurons in the adult hippocampus. One of the cellular mechanisms that could account for alterations of hippocampal structure as well as function is the regulation of adult neurogenesis. Stress exerts a profound effect on neurogenesis, leading to a rapid and prolonged decrease in the rate of cell proliferation in the adult hippocampus. In contrast, chronic antidepressant treatment up-regulates hippocampal neurogenesis, and could thereby block or reverse the atrophy and damage caused by stress. Recent studies also demonstrate that neurogenesis is required for the actions of antidepressants in behavioral models of depression. This review discusses the literature that has lead to a neurogenic hypothesis of depression and antidepressant action, as well as the molecular and cellular mechanisms that underlie the regulation of adult neurogenesis by stress and antidepressant treatment., ((c) 2006 Wiley-Liss, Inc.)

Objectives: Transverse cordotomy (TC) and medial arytenoidectomy (MA) are procedures performed to enlarge the glottic airway in patients with bilateral vocal fold paralysis (BVFP). Both are less destructive than total arytenoidectomy and have distinct theoretical advantages for voice preservation, but they have never been compared., Methods: The records of patients with BVFP treated with TC or MA were reviewed; information regarding the outcome measures of tracheotomy decannulation, dysphagia, Voice Handicap Index score, voice intensity, clinical course, and preoperative and postoperative voice quality was obtained., Results: Seventeen patients were available for evaluation (11 with TC, 6 with MA). All 6 patients with a preoperative tracheotomy were decannulated. Four patients in the MA group and 2 in the TC group had an increase in their postoperative Voice Handicap Index score. Two of the patients in the MA group had a decrease in phonatory sound pressure level of 3 dB, and 1 in the TC group had a decrease of 2 dB sound pressure level. Patient self-report of airway status following TC or MA showed that 62.5% (10 of 16) were significantly better and 25% (4 of 16) were somewhat better. Blinded audio perceptual analysis comparing preoperative and postoperative voice quality showed no difference between the MA and TC groups. A swallowing quality-of-life instrument confirmed a lack of swallowing difficulties postoperatively., Conclusions: Both TC and MA are good treatment options for BVFP, with a low incidence of complications in postoperative voice or of swallowing difficulties and a consistent improvement of laryngeal airway restriction symptoms.

Objective: This study explored the relationships between college student gender, alcohol use, protective strategies and harmful drinking consequences., Method: A derivation sample (N = 3,851; 54% women) and a replication sample (N = 4,151; 55% women) of undergraduate students completed the Campus Alcohol Survey (CAS) in classroom settings., Results: Although women drank less than men and were less likely to experience harmful consequences, they were more likely to use protective strategies. Hierarchical regression analyses revealed that students who consumed at least six drinks when they partied--especially men-were less likely to experience more common consequences (e.g., poor academic performance, property damage, unconsciousness, riding in a vehicle with others who have been drinking) if they engaged in self-protective strategies. Such strategies also helped students who exceeded the median number of drinks to moderate the effect of drinking on less common consequences (e.g., vehicular accidents, class failure, conflicts with authorities)., Conclusions: These findings add to the growing literature on contextual events that protect students from harm while drinking.

Previous studies of Staphylococcus aureus transposon insertion mutants showing decreased methicillin or teicoplanin resistance have suggested a role for the RNA polymerase alternative sigma factor SigB in the expression of resistance to these antibiotics. A knockout mutation was created in the S. aureus strain COL sigB gene and its influence on oxacillin and vancomycin resistance was studied in a variety of parental backgrounds. Typically, sigB mutants of methicillin-resistant strains had oxacillin minimum inhibitory concentrations (MICs) one-half of their parent strains. The effect of the sigB mutation appeared to be more dramatic when assessed by population analysis profiles or by growth in liquid culture in shaking flasks than by MIC determinations. Oxacillin MICs of COL and the COLDeltasigB mutant were 400 and 200 mg/l, respectively, by conventional determination and 800 and 100-200 mg/l from population analysis profiles. The COLDeltasigB mutant strain was significantly more inhibited by a range of oxacillin concentrations in a shake flask culture than strain COL. Mutation of sigB caused a decrease in vancomycin resistance in two laboratory derived glycopeptide-intermediate S. aureus strains. The results suggest that some protein products whose expression is controlled by SigB play a role in resistance to cell wall-active antibiotics.

In this paper we provide a comprehensive examination of Americans' priorities within both health and health care. We find that Americans do have a clear set of priorities in each of these areas. Americans rated cancer, human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), and heart disease, and medical research to address these conditions, as top priorities among eighty health problems. However, they did not rank many leading causes of death very high as serious problems. On the issue of health care, problems of costs, prescription drugs, and the uninsured top the list. Americans are very concerned about emerging international infectious diseases that they believe threaten their health.

The microdilution plating method, using colony-forming units (CFU)/ml determinations from 10-microl droplets, was compared with the standard plate count in population analyses of methicillin-resistant and glycopeptide-intermediate Staphylococcus aureus (MRSA and GISA) strains. Efficiency of plating plots yielded similar population resistance profiles for both methods with MRSA class 1-4 strains, laboratory-selected GISA strains of varying susceptibilities, two clinical GISA strains, as well as susceptible strains. A single heterogeneous MRSA, plated by both methods in 41 trials with and without 50 microg/ml oxacillin present, demonstrated no significant difference between the results of the two methods of colony counting (p > 0.05, and r = 0.67). Standard plating and microdilution plating produced mean resistant subpopulation determinations of one cell in 1.19 x 10(4) and 1.36 x 10(4), respectively. Population analyses carried out by microdilution plating require one-fourth or fewer of the plates used for standard plating, and both plating and colony counting required less time to perform.

A series of 12 Staphylococcus aureus strains of various genetic backgrounds, methicillin resistance levels, and autolytic activities were subjected to selection for the glycopeptide-intermediate S. aureus (GISA) susceptibility phenotype on increasing concentrations of vancomycin. Six strains acquired the phenotype rapidly, two did so slowly, and four failed to do so. The vancomycin MICs for the GISA strains ranged from 4 to 16 microg/ml, were stable to 20 nonselective passages, and expressed resistance homogeneously. Neither ease of acquisition of the GISA phenotype nor the MIC attained correlated with methicillin resistance hetero- versus homogeneity or autolytic deficiency or sufficiency. Oxacillin MICs were generally unchanged between parent and GISA strains, although the mec members of both isogenic methicillin-susceptible and methicillin-resistant pairs acquired the GISA phenotype more rapidly and to higher MICs than did their susceptible counterparts. Transmission electron microscopy revealed that the GISA strains appeared normal in the absence of vancomycin but had thickened and diffuse cell walls when grown with vancomycin at one-half the MIC. Common features among GISAs were reduced doubling times, decreased lysostaphin susceptibilities, and reduced whole-cell and zymographic autolytic activities in the absence of vancomycin. This, with surface hydrophobicity differences, indicated that even in the absence of vancomycin the GISA cell walls differed from those of the parents. Autolytic activities were further reduced by the inclusion of vancomycin in whole-cell and zymographic studies. The six least vancomycin-susceptible GISA strains exhibited an increased capacity to remove vancomycin from the medium versus their parent lines. This study suggests that while some elements of the GISA phenotype are strain specific, many are common to the phenotype although their expression is influenced by genetic background. GISA strains with similar glycopeptide MICs may express individual components of the phenotype to different extents.

SHP female mice were fed 100 mg/kg carbonic fibrilous sorbent Akvalen 5 times a week, from the age of 3 months until death. The treatment failed to have a significant influence on body weight dynamics or mean lifespan. However, sorbent-treated animals survived 4 months longer until 90% of them died. Although there were no significant differences in the frequency of either all or only malignant tumors between study group and controls, the former showed fewer multiple tumors (1.4 times) as well as a tendency of decreased incidence of neoplasms of the hemopoietic system and uterine polyps. Tumor-bearing sorbent-treated mice survived 4 months longer, while those with malignant tumors only survived 5 months longer (p < 0.05). The investigation failed to detect any carcinogenicity of Akvalen. It is suggested that the sorbent possesses certain geroprotective and anti-tumor properties.

Objective: To identify factors related to increased or decreased risk of thromboembolism (TE) in patients with high-grade glioma., Design: We performed a retrospective analysis of 64 patients enrolled in two prospective clinical trials of chemotherapy and radiation therapy for newly diagnosed high-grade glioma., Material and Methods: The 64 patients were 18 years of age or older and had histologically confirmed grade 3 or 4 astrocytoma, mixed astrocytoma-oligodendroglioma, or gliosarcoma. The diagnosis of TE was confirmed by impedance plethysmography, venography, duplex ultrasonography, ventilation-perfusion lung scanning, or pulmonary angiography. For statistical analysis, the study group was divided into those with and those without TE., Results: TE developed in 18 of the 64 patients (28%). Of the 18 patients, 11 had deep venous thrombosis of a lower extremity, 5 had pulmonary emboli, and 2 had superficial thrombophlebitis. A paretic arm (P = 0.017), a paretic leg (P = 0.026), or a history of TE before the diagnosis of glioma (P = 0.076) was more common in patients with TE than in those without TE. Ten patients in the group without TE were using aspirin preoperatively in comparison with no patient in the TE group (P = 0.05). No significant differences were noted in duration of survival (median, 39.4 weeks and 46 weeks for the TE and non-TE groups, respectively). One patient with apparently excessive anticoagulation had a fatal intracerebral hemorrhage., Conclusion: This study suggests that TE in patients with newly diagnosed high-grade glioma might be associated with a history of TE or with a paretic extremity; however, no evidence of worse survival was noted in the TE group. Treatment with heparin followed by warfarin sodium was associated with infrequent bleeding complications. An intriguing finding was that the use of aspirin before operation was associated with a decreased risk of TE. Thus, a prospective study with use of aspirin in patients with high-grade glioma at risk for TE would be reasonable.

To evaluate sinus mucosal regeneration and cilia motility after surgical removal, 15 rabbits underwent unilateral removal of maxillary sinus mucosa. The opposite sinus served as an unoperated control. After 10 weeks, specimens were taken for examination from all operated on and control sinuses. Light, dark-field, and electron microscopy were performed. Mucosa from eight of the 15 sinuses operated on showed ciliary regeneration by light microscopy; six of these exhibited motile cilia on dark-field examination. Histopathologic findings of marked fibrosis, decreased seromucinous glands, and significant inflammation were commonly present in the sinuses operated on. Electron microscopy revealed frequent abnormalities, including complex and edematous cilia and fewer than normal cilia per unit area compared to controls. The dark-field, light, and electron microscopic findings of the regenerated, post-surgical mucosa are discussed.

Olfactory neuroblastomas are rare tumors whose clinical prognosis is not predictable by assessment of initial stage or grade. The pathologic diagnosis is often difficult because of the wide range of the patient's age and histologies. In this report, we document that the diagnosis of olfactory neuroblastoma can be clarified by immunohistochemical demonstration of a unique antigenic profile that can be obtained in routinely processed biopsies. We describe four cases of olfactory neuroblastoma diagnosed and treated from 1979 to 1989, each confirmed by immunohistology. One of our patients was misdiagnosed twice at an outside institution, first as having nasopharyngeal carcinoma and then as having small-cell, undifferentiated "oat cell" carcinoma. Despite accurate tumor diagnosis and appropriate therapy, we found that there was no apparent correlation of clinical outcome with Kadish clinical stage or histologic grade of tumor.

Preoperative coagulation profile screening is routinely performed in otolaryngology before tonsillectomy and adenoidectomy surgery in the United States. Recently there has been controversy as to whether this routine testing is necessary. To evaluate the need for this testing, we reviewed a series of patients with particular attention to abnormal coagulation profiles. Of 91 consecutive patients undergoing tonsillectomy, adenoidectomy, or both, four had abnormal preoperative coagulation profiles. Of these patients, one had von Willebrand disease, one had hypofibrinoginemia, and two had a transient acquired lupus-like anticoagulant. The latter condition, which causes a temporary prolongation of the activated partial thromboplastin time, is discussed in detail along with a review of the pertinent literature. We conclude that coagulopathies occur frequently enough to justify preoperative screening even in the absence of a positive history.

The cause of platelet agglutination in thrombotic thrombocytopenic purpura has been an enigma. Current evidence indicates that the interaction of platelets with a platelet-aggregating factor or unusually large multimers of factor VIII: von Willebrand factor, or both, may cause the abnormal platelet agglutination. Recent success in the treatment of thrombotic thrombocytopenic purpura with intravenous infusion of immunoglobulin suggests that the abnormal platelet agglutination in thrombotic thrombocytopenic purpura may reflect a deficiency of immunoglobulins that normally inhibit platelet-aggregating factors or large multimers of factor VIII: von Willebrand factor.