Safety and tolerability of transcranial magnetic and direct current stimulation in children: Prospective single center evidence from 3.5 million stimulations.

BACKGROUND: Non-invasive brain stimulation is being increasingly used to interrogate neurophysiology and modulate brain function. Despite the high scientific and therapeutic potential of non-invasive brain stimulation, experience in the developing brain has been limited. OBJECTIVE: To determine the safety and tolerability of non-invasive neurostimulation in children across diverse modalities of stimulation and pediatric populations. METHODS: A non-invasive brain stimulation program was established in 2008 at our pediatric, academic institution. Multi-disciplinary neurophysiological studies included single- and paired-pulse Transcranial Magnetic Stimulation (TMS) methods. Motor mapping employed robotic TMS. Interventional trials included repetitive TMS (rTMS) and transcranial direct current stimulation (tDCS). Standardized safety and tolerability measures were completed prospectively by all participants. RESULTS: Over 10 years, 384 children underwent brain stimulation (median 13 years, range 0.8-18.0). Populations included typical development (n = 118), perinatal stroke/cerebral palsy (n = 101), mild traumatic brain injury (n = 121) neuropsychiatric disorders (n = 37), and other (n = 7). No serious adverse events occurred. Drop-outs were rare (<1%). No seizures were reported despite >100 participants having brain injuries and/or epilepsy. Tolerability between single and paired-pulse TMS (542340 stimulations) and rTMS (3.0 million stimulations) was comparable and favourable. TMS-related headache was more common in perinatal stroke (40%) than healthy participants (13%) but was mild and self-limiting. Tolerability improved over time with side-effect frequency decreasing by >50%. Robotic TMS motor mapping was well-tolerated though neck pain was more common than with manual TMS (33% vs 3%). Across 612 tDCS sessions including 92 children, tolerability was favourable with mild itching/tingling reported in 37%. CONCLUSIONS: Standard non-invasive brain stimulation paradigms are safe and well-tolerated in children and should be considered minimal risk. Advancement of applications in the developing brain are warranted. A new and improved pediatric NIBS safety and tolerability form is included.

An evaluation of health protection practices for the investigation and management of Cryptosporidium in England and Wales.

Background: Cryptosporidium is a major cause of gastroenteritis (cryptosporidiosis). Case and outbreak report rates vary geographically, which may in part reflect public health practice. Methods: To examine the public health management of cryptosporidiosis, an online questionnaire was administered to the 28 Health Protection Teams (HPTs) in England and Wales in 2014. Practices for investigation and management of cases and outbreaks were compared. Results: Practice varied among the 24 (86%) respondents in terms of who undertook actions (HPT or Local Authority) to investigate and manage cryptosporidiosis. HPTs without exceedance monitoring detected fewer outbreaks (1/5, 20%) than those with it (13/19, 68%) (P = 0.12), and those that always administered a risk-factor questionnaire detected more outbreaks (12/19, 63%) than those who did this only sometimes (2/5, 40%) (P = 0.62). Significantly more HPTs with a system to detect common exposures reported at least one outbreak (14/19, 74%) compared to HPTs with no system (0/5) (P = 0.01). Conclusions: Applying exceedance monitoring, using a standardized questionnaire taking into account the incubation period for Cryptosporidium, and having a structured system to detect common exposures increased outbreak detection. Information about all cases should be shared between local public health authorities, and current guidance used for the prevention of spread.

A randomised placebo-controlled trial to explore the effect of suppressive therapy with acyclovir on genital shedding of HIV-1 and herpes simplex virus type 2 among Zimbabwean sex workers.

OBJECTIVES: To determine the effect of daily acyclovir on genital shedding of HIV-1 and herpes simplex virus type 2 (HSV-2) in a randomised placebo-controlled trial among rural Zimbabwean sex workers. METHODS: 214 women were recruited and tested for HIV-1 and HSV-2 antibodies, HIV plasma viral load, CD4 lymphocyte count and genital swabs for qualitative detection of HIV-1 and HSV-2 genital shedding. Women were randomly assigned to acyclovir 400 mg twice a day for 12 weeks or matching placebo and were followed weekly to detect HIV-1 or HSV-2 genital shedding. Shedding analyses were only undertaken on 125 women co-infected with HSV-2 and HIV-1. Data were analysed using logistic regression, with random effects modelling used to account for repeated measurements on the same women. RESULTS: All women were randomly assigned to acyclovir or placebo; 125 of whom were co-infected with HIV-1 and HSV-2. 69 women were randomly assigned to acyclovir and 56 to placebo. Although twice daily acyclovir reduced rates of HSV-2 genital shedding, (adjusted odds ratio (AOR) 0.24; 95% CI 0.12 to 0.48; less than p<0.001), it had no effect on the proportion of visits at which HIV-1 shedding was detected (AOR 1.08; 95% CI 0.48 to 2.42; p = 0.9). Adherence varied between participants but even when adherence was high (as determined by pill count and extent of HSV-2 suppression) HIV-1 shedding was not reduced. CONCLUSION: Among these HIV-1 and HSV-2-seropositive women, suppressive acyclovir therapy had no effect on the rate of HIV genital shedding despite a reduction in genital HSV-2. Treatment adherence and its measurement clearly affect the interpretation of these results.

The DNA sequence and biological annotation of human chromosome 1.

The reference sequence for each human chromosome provides the framework for understanding genome function, variation and evolution. Here we report the finished sequence and biological annotation of human chromosome 1. Chromosome 1 is gene-dense, with 3,141 genes and 991 pseudogenes, and many coding sequences overlap. Rearrangements and mutations of chromosome 1 are prevalent in cancer and many other diseases. Patterns of sequence variation reveal signals of recent selection in specific genes that may contribute to human fitness, and also in regions where no function is evident. Fine-scale recombination occurs in hotspots of varying intensity along the sequence, and is enriched near genes. These and other studies of human biology and disease encoded within chromosome 1 are made possible with the highly accurate annotated sequence, as part of the completed set of chromosome sequences that comprise the reference human genome.

Decreased adenosine receptor binding in dystonic brains of the dt(sz) mutant.

In patients with paroxysmal non-kinesigenic dyskinesias, episodes of dystonia can be provoked by stress and also by methylxanthines (e.g. caffeine), which inhibit adenosine A(1)/A(2A) receptors. In the dt(sz) mutant hamster, a model of this movement disorder, adenosine A(1) receptor antagonists were previously found to worsen dystonia, while adenosine A(1) and A(2A) receptor agonists exerted pronounced beneficial effects. Therefore, in the present study, adenosine receptor A(1) and A(2A) binding was determined by autoradiographic analyses in dt(sz) hamsters under basal conditions, i.e. in the absence of a dystonic attack, and in a group of mutant hamsters which exhibited severe stress-induced dystonic attacks prior to kill. In comparison with non-dystonic control hamsters, [(3)H]DPCPX (8-cyclopentyl-1,3-dipropylxanthine) binding to adenosine A(1) receptors and [(3)H]CGS 21680 (2p-(2carboxyethylphen-ethylamino-5'-N-ethlycarboxamindoadenosine) binding to adenosine A(2A) receptors were significantly lower throughout the brain of dystonic animals. Under normal resting conditions, mutant hamsters showed significant decreases in adenosine A(1) (-12 to-42%) and in A(2A) (-19 to-34%) receptor binding compared with controls. Stressful stimulation increased adenosine A(1) and A(2A) receptor binding in almost all brain regions in both control and dystonic hamsters. The stress-induced increase was more marked in mutant hamsters, leading to a disappearance of differences in most regions compared with stimulated controls, except the striatum. In view of previous findings of striking beneficial effects of adenosine A(1) and A(2A) receptor agonists and of striatal dysfunctions in the dt(sz) mutant, the reduced adenosine receptor binding may be an important factor in the pathogenesis of paroxysmal dystonia.

DNA sequence and analysis of human chromosome 9.

Chromosome 9 is highly structurally polymorphic. It contains the largest autosomal block of heterochromatin, which is heteromorphic in 6-8% of humans, whereas pericentric inversions occur in more than 1% of the population. The finished euchromatic sequence of chromosome 9 comprises 109,044,351 base pairs and represents >99.6% of the region. Analysis of the sequence reveals many intra- and interchromosomal duplications, including segmental duplications adjacent to both the centromere and the large heterochromatic block. We have annotated 1,149 genes, including genes implicated in male-to-female sex reversal, cancer and neurodegenerative disease, and 426 pseudogenes. The chromosome contains the largest interferon gene cluster in the human genome. There is also a region of exceptionally high gene and G + C content including genes paralogous to those in the major histocompatibility complex. We have also detected recently duplicated genes that exhibit different rates of sequence divergence, presumably reflecting natural selection.

The DNA sequence and analysis of human chromosome 13.

Chromosome 13 is the largest acrocentric human chromosome. It carries genes involved in cancer including the breast cancer type 2 (BRCA2) and retinoblastoma (RB1) genes, is frequently rearranged in B-cell chronic lymphocytic leukaemia, and contains the DAOA locus associated with bipolar disorder and schizophrenia. We describe completion and analysis of 95.5 megabases (Mb) of sequence from chromosome 13, which contains 633 genes and 296 pseudogenes. We estimate that more than 95.4% of the protein-coding genes of this chromosome have been identified, on the basis of comparison with other vertebrate genome sequences. Additionally, 105 putative non-coding RNA genes were found. Chromosome 13 has one of the lowest gene densities (6.5 genes per Mb) among human chromosomes, and contains a central region of 38 Mb where the gene density drops to only 3.1 genes per Mb.

The DNA sequence and analysis of human chromosome 6.

Chromosome 6 is a metacentric chromosome that constitutes about 6% of the human genome. The finished sequence comprises 166,880,988 base pairs, representing the largest chromosome sequenced so far. The entire sequence has been subjected to high-quality manual annotation, resulting in the evidence-supported identification of 1,557 genes and 633 pseudogenes. Here we report that at least 96% of the protein-coding genes have been identified, as assessed by multi-species comparative sequence analysis, and provide evidence for the presence of further, otherwise unsupported exons/genes. Among these are genes directly implicated in cancer, schizophrenia, autoimmunity and many other diseases. Chromosome 6 harbours the largest transfer RNA gene cluster in the genome; we show that this cluster co-localizes with a region of high transcriptional activity. Within the essential immune loci of the major histocompatibility complex, we find HLA-B to be the most polymorphic gene on chromosome 6 and in the human genome.

Changes in AMPA receptor binding in an animal model of inborn paroxysmal dystonia.

Previous pharmacological studies suggested that glutamatergic overactivity contributes to manifestation of dystonic attacks in mutant hamsters (dt(sz)), a model of idiopathic paroxysmal dystonia in which episodes of dystonia occur in response to stress. In the present study, [(3)H]AMPA (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate) receptor binding was determined by autoradiographic analyses in 41 brain (sub)regions of dt(sz) hamsters under basal conditions, i.e., in the absence of dystonia, and in a group of mutant hamsters that exhibited severe stress-induced dystonic attacks immediately prior to sacrifice. In comparison to nondystonic control hamsters the basal [(3)H]AMPA binding was significantly higher in the ventromedial and ventrolateral caudate putamen, the anterior cingulate cortex, the hippocampus, and the lateral septum of dystonic brains. During dystonic attacks the [(3)H]AMPA binding was significantly lower in the dorsomedial, dorsolateral, and posterior caudate putamen; the ventromedial thalamus; and the frontal cortex of mutant hamsters compared with control animals that were exposed to the same external stimulation. The basal increase in AMPA receptor density within limbic structures may contribute to the susceptibility of stress-inducible dystonic episodes in mutant hamsters. Since AMPA receptor activation is known to cause a fast reduction of the affinity and an internalization of postsynaptic AMPA receptors, the latter finding could reflect a glutamatergic overactivity within the striato-thalamo-cortical circuit during the expression of dystonia, which is in line with previous neurochemical and pharmacological data in dt(sz) hamsters.

Drug-induced receptor occupancy: substantial differences in measurements made in vivo vs ex vivo.

RATIONALE: The number of receptors occupied by a given drug is a central construct in understanding drug action in the brain. Two techniques have been commonly used to measure drug receptor occupancy. In one method, the drug and the radioligand used to measure occupancy compete in vivo while in the other method, the drug is injected into the living animal, the animal killed and the radioligand competes for available receptors ex vivo. While these methods are often used interchangeably, there has been no systematic comparison of their sensitivities and consistency. OBJECTIVES: In this study, we performed a systematic within-animal comparison of drug-induced receptor occupancy as measured by the in vivo vs the ex vivo methods. METHODS: We examined the occupancy of dopamine Do receptors by different doses of the drug raclopride using the in vivo and ex vivo autoradiographic methods in the same rat with 11C-raclopride and 3H-raclopride as radioligands, respectively. RESULTS: The in vivo method showed a significantly greater sensitivity and internal consistency while the ex vivo method was less sensitive, and increasingly so as a function of longer incubation times. The lack of sensitivity was accounted for by the unidirectional dissociation of the drug from the receptors in the incubation medium. CONCLUSIONS: Our data suggest that these two methods are not interchangeable; the ex vivo method is much less sensitive, lacks internal consistency and hence is best avoided.

Seroconversion to HIV-1 following a needlestick injury despite combination post-exposure prophylaxis.

Post-exposure prophylaxis with antiretroviral drugs for at-risk needlestick injuries has become routine practice and is usually empirical. With increasing numbers of treatment-experienced patients, the choice of antiretroviral may need to be individually tailored. Infection can still occur despite attempts to optimize the drug combination used.

National surveillance of HIV-1 subtypes for England and Wales: design, methods, and initial findings.

The HIV-1 infections detected in an ongoing national unlinked anonymous HIV surveillance program were subtyped and analyzed according to demographic and risk characteristics. Of the 893 anti--HIV-1--positive specimens allocated to an exposure group, 70% could be subtyped. Almost 25% of infections subtyped were non-B, mostly subtypes A, C, and D. Non-B infections were rare in homosexual and bisexual men and in drug injectors. Forty percent of infections in heterosexual men attending genitourinary medicine clinics were non-B subtypes; of these, 25% were subtype A infections and 59% were subtype C infections. For female clinic attendees, 61% were non-B subtype infections, of which 48% were subtype A infections and 42% were subtype C infections. Of the clinic attendees born in the United Kingdom and Europe, 14% of the men and 35% of the women were infected with non-B subtypes. In contrast, 78% of infections in antenatal patients were non-B subtypes, of which 61% were subtype A and 29% were subtype C. Extrapolation to the estimated 29,700 prevalent adult infections in the United Kingdom indicates that approximately 8,100 (27%) such infections are non-B subtypes and that these are found almost entirely in heterosexuals. The findings suggest spread of infection of non-B subtypes to heterosexuals born in the United Kingdom from individuals infected in regions of high prevalence.

Recombinant strains of HIV type 1 in the United Kingdom.

Twenty-five recombinant (mosaic) HIV-1 genomes were detected among 151 samples comprising 118 non-B subtype sequences and 33 samples containing subtype B sequences. Seven of the 25 mosaic patterns were similar to characterized circulating recombinant forms (two A/E, four A/G, and one D/F) and one was a MAL-like A/D recombinant. Eighteen of the recombinants had evidence of subtype A sequences in at least one region of their genome. One sample was found to contain a novel recombinant form (pol F, env K). Two samples could not be characterized unambiguously as recombinant forms and a further one appeared to be a complex C/J/D/A genomic form. The majority of the mosaic genomes were recombinants between gag, pol, or env, whereas the C/J/D/A mosaic had cross-over breakpoints within pol. These findings suggest that almost 20% of non-B subtype isolates of HIV-1 circulating in the United Kingdom have mosaic genomes. This shows the diverse origin of HIV-1 strains circulating in the United Kingdom and may have implications for antiretroviral drug resistance.

The DNA sequence and comparative analysis of human chromosome 20.

The finished sequence of human chromosome 20 comprises 59,187,298 base pairs (bp) and represents 99.4% of the euchromatic DNA. A single contig of 26 megabases (Mb) spans the entire short arm, and five contigs separated by gaps totalling 320 kb span the long arm of this metacentric chromosome. An additional 234,339 bp of sequence has been determined within the pericentromeric region of the long arm. We annotated 727 genes and 168 pseudogenes in the sequence. About 64% of these genes have a 5' and a 3' untranslated region and a complete open reading frame. Comparative analysis of the sequence of chromosome 20 to whole-genome shotgun-sequence data of two other vertebrates, the mouse Mus musculus and the puffer fish Tetraodon nigroviridis, provides an independent measure of the efficiency of gene annotation, and indicates that this analysis may account for more than 95% of all coding exons and almost all genes.

Prevalence and precipitants of aggression in psychiatric inpatient units.

OBJECTIVE: Aggression is a significant clinical problem in psychiatric facilities. The present study reviews data on aggression collected from psychiatric inpatient units in order to determine prevalence and causal factors. METHOD: Data on aggressive incidents were gathered from four adult psychiatric units in the Illawarra, Australia. Information obtained included diagnosis, causal factors and patient sociodemographic characteristics. RESULTS: During the 18-month period, a total of 1269 psychiatric patients were admitted and 174 patients (13.7%) were recorded as being aggressive. Patients with bipolar affective disorder and schizophrenia had a 2.81 and 1.96 significantly increased risk of aggression, respectively, while depression and adjustment disorder conferred a significantly lower risk. Aggression was most likely to occur within 2 days of admission and length of stay was greater for aggressive than non-aggressive patients. The greater number of incidents occurred on day shift. Most patients who displayed aggression did so on one occasion, but a small proportion of total patients (6.0%) accounted for a large number of incidents (71.0%). High-risk patients were identified as those who were under 32 years of age, were actively psychotic, detained and known to have a history of aggression and substance misuse. The most frequent form of aggression was physical and staff were most often the victims. CONCLUSIONS: These results have important implications for predicting and thereby reducing inpatient aggression. Organisations need to ensure aggression management strategies are in place and periodically identify and assess the level of risk for workers.

Annual incidence of shaken impact syndrome in young children.

We looked at the incidence and demography of nonaccidental head injury in children in a prospective population-based study of paediatric units in Scotland during 1998-99. Shaken impact syndrome occurs with an annual incidence of 24.6 per 100000 children younger than 1 year (95% CI 14.9-38.5). Cases are more common in urban regions, and during autumn and winter months. The risk of a child suffering non-accidental head injury by age 1 year is one in 4065. These brain injuries occur almost exclusively in young infants (median age 2.2 months).

Ethnicity in America and feeling "American".

Ethnic group acculturation remains a concern in the United States today. In the present study, the authors explored the extent to which members of three ethnic groups (White American women, African American women, and Cuban American women) perceived themselves to be "American," how much each group felt that its members were perceived as being American by White Americans, and how these perceptions related to beliefs about their own group's economic and social status. The results showed that African Americans felt American but felt that they were not perceived as such by White Americans. African Americans also reported feeling economically and socially excluded. In contrast, Cuban Americans reported neither feeling they were American nor believing they were perceived as such by White Americans, but feelings of inclusion increased with length of residence. Implications of these results for the common ingroup identity model are discussed.

Early posttraumatic seizures in non-accidental head injury: relation to outcome.

To document the characteristics of early posttraumatic seizures (EPTS) in non-accidental head injury (NAHI), and examine their relation with outcome, a retrospective study was carried out. All children with NAHI admitted to the Royal Hospital for Sick Children, Edinburgh, since 1981 were identified. The characteristics of EPTS, EEG, and outcome were noted. Forty-four cases were identified. The average age of children at presentation was 5.9 months. Thirty-two of these children had EPTS. The median length of follow-up was 3 years. The mortality rate was six in 44 (14%). The neurodevelopmental outcome correlated significantly with the presence and severity of EPTS (Tau=0.317,p=0.017). Of survivors, 22% developed late posttraumatic epilepsy; the outcome in those with epilepsy was significantly worse than those without (p<0.0001). It was concluded that the severity of the primary brain injury dictates the severity of the EPTS and neurodevelopmental status at follow-up.

Viral genome characterisation by the heteroduplex mobility and heteroduplex tracking assays.

The heteroduplex mobility assay (HMA) is a means of comparing two PCR amplicons or, in the variation known as the heteroduplex tracking assay (HTA), a means of estimating the quasispecies diversity of a viral genome. Heteroduplex assays have many applications including subtyping viral genomes, screening for low frequency variants in a population, scanning the relative genetic diversity across a genome and screening for recombinant clones. They can be used to detect dual infections, superinfections, contaminated blood products and laboratory contaminations. PCR amplicons of about 65% sequence similarity or greater will form heteroduplexes under appropriate conditions, and phylogenetic trees can be drawn from heteroduplex mobility data. While homoduplexes indicate more than 98% similarity between two DNA sequences, heteroduplexes indicate at least seven mismatches in a 500-bp amplicon, or a three-base pair gap in 1000-bp. Minority variants comprising 1% to 5% of the genome population can be detected and quantified by HTA. Thus far, heteroduplex assays have been described for HIV and other lentiviruses, hepatitis C and G viruses, Norwalk-like viruses, influenza, measles and poliovirus. They could be applied to a wide range of other viral species.