ANKS1B encoded AIDA-1 regulates social behaviors by controlling oligodendrocyte function.

Heterozygous deletions in the ANKS1B gene cause ANKS1B neurodevelopmental syndrome (ANDS), a rare genetic disease characterized by autism spectrum disorder (ASD), attention deficit/hyperactivity disorder, and speech and motor deficits. The ANKS1B gene encodes for AIDA-1, a protein that is enriched at neuronal synapses and regulates synaptic plasticity. Here we report an unexpected role for oligodendroglial deficits in ANDS pathophysiology. We show that Anks1b-deficient mouse models display deficits in oligodendrocyte maturation, myelination, and Rac1 function, and recapitulate white matter abnormalities observed in ANDS patients. Selective loss of Anks1b from the oligodendrocyte lineage, but not from neuronal populations, leads to deficits in social preference and sensory reactivity previously observed in a brain-wide Anks1b haploinsufficiency model. Furthermore, we find that clemastine, an antihistamine shown to increase oligodendrocyte precursor cell maturation and central nervous system myelination, rescues deficits in social preference in 7-month-old Anks1b-deficient mice. Our work shows that deficits in social behaviors present in ANDS may originate from abnormal Rac1 activity within oligodendrocytes.

Life-Limiting Peripheral Organ Dysfunction in Feline Sandhoff Disease Emerges after Effective CNS Gene Therapy.

OBJECTIVE: GM2 gangliosidosis is usually fatal by 5 years of age in its 2 major subtypes, Tay-Sachs and Sandhoff disease. First reported in 1881, GM2 gangliosidosis has no effective treatment today, and children succumb to the disease after a protracted neurodegenerative course and semi-vegetative state. This study seeks to further develop adeno-associated virus (AAV) gene therapy for human translation. METHODS: Cats with Sandhoff disease were treated by intracranial injection of vectors expressing feline ß-N-acetylhexosaminidase, the enzyme deficient in GM2 gangliosidosis. RESULTS: Hexosaminidase activity throughout the brain and spinal cord was above normal after treatment, with highest activities at the injection sites (thalamus and deep cerebellar nuclei). Ganglioside storage was reduced throughout the brain and spinal cord, with near complete clearance in many regions. While untreated cats with Sandhoff disease lived for 4.4 ± 0.6 months, AAV-treated cats lived to 19.1 ± 8.6 months, and 3 of 9 cats lived >21 months. Correction of the central nervous system was so effective that significant increases in lifespan led to the emergence of otherwise subclinical peripheral disease, including megacolon, enlarged stomach and urinary bladder, soft tissue spinal cord compression, and patellar luxation. Throughout the gastrointestinal tract, neurons of the myenteric and submucosal plexuses developed profound pathology, demonstrating that the enteric nervous system was inadequately treated. INTERPRETATION: The vector formulation in the current study effectively treats neuropathology in feline Sandhoff disease, but whole-body targeting will be an important consideration in next-generation approaches. ANN NEUROL 2023;94:969-986.

Effect of Physical Exercise and Genetic Background on Glucose Homeostasis and Liver/Muscle Proteomes in Mice.

We compared the parameters related to glucose homeostasis, and liver and muscle proteomes in fluorosis-susceptible (A/J; S) and fluorosis-resistant (129P3/J; R) mice in response to fluoride (F) exposure and exercise. Ninety male mice (45 R-mice and 45 S-mice) were randomized into three groups: (SI; RI) No-F, No-Exercise, (SII; RII) 50 ppm F, No-Exercise, (SIII; RIII) 50 ppm F, Exercise. Overall, mean F concentrations in the plasma and femur were significantly higher in R-mice compared with S-mice. In R-mice, exercise resulted in an increase in F accumulation in the femur. In S-mice, the mean plasma glucose level was significantly higher in Group II compared with Groups I and III. There was an increase in liver proteins involved in energy flux and antioxidant enzymes in non-exercise groups (I, II) of S-mice in comparison with the corresponding groups of R-mice. The results also showed a decrease in muscle protein expression in Group I S-mice compared with their R-mice counterparts. In conclusion, the findings suggest an increased state of oxidative stress in fluorosis-susceptible mice that might be exacerbated by the treatment with F. In addition, fluorosis-susceptible mice have plasma glucose levels higher than fluorosis-resistant mice on exposure to F, and this is not affected by exercise.

Real-time MR tracking of AAV gene therapy with ßgal-responsive MR probe in a murine model of GM1-gangliosidosis.

Transformative results of adeno-associated virus (AAV) gene therapy in patients with spinal muscular atrophy and Leber's congenital amaurosis led to approval of the first two AAV products in the United States to treat these diseases. These extraordinary results led to a dramatic increase in the number and type of AAV gene-therapy programs. However, the field lacks non-invasive means to assess levels and duration of therapeutic protein function in patients. Here, we describe a new magnetic resonance imaging (MRI) technology for real-time reporting of gene-therapy products in the living animal in the form of an MRI probe that is activated in the presence of therapeutic protein expression. For the first time, we show reliable tracking of enzyme expression after a now in-human clinical trial AAV gene therapy (ClinicalTrials.gov: NTC03952637) encoding lysosomal acid beta-galactosidase (ßgal) using a self-immolative ßgal-responsive MRI probe. MRI enhancement in AAV-treated enzyme-deficient mice (GLB-1-/-) correlates with ßgal activity in central nervous system and peripheral organs after intracranial or intravenous AAV gene therapy, respectively. With >1,800 gene therapies in phase I/II clinical trials (ClinicalTrials.gov), development of a non-invasive method to track gene expression over time in patients is crucial to the future of the gene-therapy field.

White Matter Pathology as a Barrier to Gangliosidosis Gene Therapy.

The gangliosidoses are a family of neurodegenerative lysosomal storage diseases that have recently seen promising advances in gene therapy. White matter deficits are well established components of gangliosidosis pathology that are now receiving more attention because they are partially refractory to correction by gene therapy. After a brief synopsis of normal myelinogenesis, this review outlines current viewpoints on the origin of white matter deficits in the gangliosidoses and potential obstacles to treating them effectively by gene therapy. Dysmyelinogenesis (failure of myelin sheaths to form properly) is proposed as the predominant contributor to white matter pathology, but precise mechanistic details are not well understood. The involvement of neuronal storage deficits may extend beyond secondary demyelination (destruction of myelin due to axonal loss) and contribute to dysmyelinogenesis. Preclinical studies in animal models of the gangliosidoses have substantially improved lifespan and quality of life, leading to the initiation of several clinical trials. However, improvement of white matter pathology has lagged behind other metrics and few evidence-based explanations have been proposed to date. Research groups in the field are encouraged to include myelin-specific investigations in future gene therapy work to address this gap in knowledge.

GM1 Gangliosidosis: Mechanisms and Management.

The lysosomal storage disorder, GM1 gangliosidosis (GM1), is a neurodegenerative condition resulting from deficiency of the enzyme ß-galactosidase (ß-gal). Mutation of the GLB1 gene, which codes for ß-gal, prevents cleavage of the terminal ß-1,4-linked galactose residue from GM1 ganglioside. Subsequent accumulation of GM1 ganglioside and other substrates in the lysosome impairs cell physiology and precipitates dysfunction of the nervous system. Beyond palliative and supportive care, no FDA-approved treatments exist for GM1 patients. Researchers are critically evaluating the efficacy of substrate reduction therapy, pharmacological chaperones, enzyme replacement therapy, stem cell transplantation, and gene therapy for GM1. A Phase I/II clinical trial for GM1 children is ongoing to evaluate the safety and efficacy of adeno-associated virus-mediated GLB1 delivery by intravenous injection, providing patients and families with hope for the future.

Pharmacokinetics of fluoride in human adults: The effect of exercise.

The literature is sparse in terms of the effect of exercise on the pharmacokinetics of fluoride (F) in humans. In a 4-treatment repeated measures cross-over study, we investigated F pharmacokinetics following no exercise (control) and three exercise intensity conditions (light, moderate and vigorous) in healthy adults. At a pre-experimental session, 8 participants (18-30y) residing in a non-fluoridated-area, underwent a VO2 max test to guide the three exercise intensities for the experimental sessions. Participants were on a F-free regime one week before and throughout the four experimental weeks. We measured urinary F excretion (UFE), maximum plasma concentration (Cmax), lag time of Cmax (Tmax), and Area Under the Curve (AUC) for plasma F concentration against time, following F ingestion then no, light, moderate and vigorous exercise. Results showed no statistically significant difference in Tmax among all sessions; whereas Cmax for moderate exercise (226.2 ng/ml) was significantly higher than for no (27.0 ng/ml; p < 0.001), light (105.6 ng/ml; p = 0.016) and vigorous (94.2 ng/ml; p = 0.008) exercise. Mean AUC over 0-90 min following F ingestion was also significantly higher in moderate exercise than for no (p < 0.001), light (p = 0.004) and vigorous (p = 0.001) exercise. Mean UFE over 0-14h was 638.8, 718.7, 574.6 and 450.5  µg for no, light, moderate and vigorous exercise, with no statistically significant differences among different sessions. In conclusion, this human experimental study suggests that moderate exercise may increase the fraction of F absorbed systemically which is therefore available to produce a biological effect. Future studies should be conducted with larger samples, different age groups and using different F doses.

Whole-slide image analysis outperforms micrograph acquisition for adipocyte size quantification.

The distinction between biological processes of adipose tissue expansion is crucial to understanding metabolic derangements, but a robust method for quantifying adipocyte size has yet to be standardized. Here, we compared three methods for histological analysis in situ: one conventional approach using individual micrographs acquired by digital camera, and two with whole-slide image analysis pipelines involving proprietary (Visiopharm) and open-source software (QuPath with a novel ImageJ plugin). We found that micrograph analysis identified 10-40 times fewer adipocytes than whole-slide methods, and this small sample size resulted in high variances that could lead to statistical errors. The agreement of the micrograph method to measure adipocyte area with each of the two whole-slide methods was substantially less (R2 of 0.6644 and 0.7125) than between the two whole-slide methods (R2 of 0.9402). These inconsistencies were more pronounced in samples from high-fat diet fed mice. While the use of proprietary software resulted in the highest adipocyte count, the lower cost, ease of use, and minimal variances of the open-source software provided a distinct advantage for measuring the number and size of adipocytes. In conclusion, we recommend whole-slide image analysis methods to consistently measure adipocyte area and avoid unintentional errors due to small sample sizes.

The FiCTION trial: Child oral health-related quality of life and dental anxiety across three treatment strategies for managing caries in young children.

OBJECTIVES: The FiCTION trial compared co-primary outcomes (dental pain and/or infection) and secondary outcomes (child oral health-related quality of life [COHRQOL], child dental anxiety, cost-effectiveness, caries development/progression and acceptability) across three treatment strategies (Conventional with Prevention [C + P]; Biological with Prevention [B + P]; Prevention Alone [PA]) for managing caries in children in primary care. COHRQOL and child dental anxiety experiences are reported upon here. METHODS: A multi-centre, 3-arm, parallel-group, unblinded patient-randomized controlled trial of 3- to 7-year-olds treated under NHS contracts was conducted in 72 general dental practices in England, Wales and Scotland. Child participants (with at least one primary molar with dentinal caries) were randomized (1:1:1) to one of three treatment arms with the intention of being managed according to allocated arm for 3 years (minimum 23 months). Randomization was via a centrally administered system using random permuted blocks of variable length. At baseline and final visit, accompanying parents/caregivers completed a parental questionnaire including COHRQOL (16 item P-CPQ-16), and at every visit, child- and parental-questionnaire-based data were collected for child-based dental trait and state anxiety. Statistical analyses were conducted on complete cases from the modified intention-to-treat (mITT) analysis set. RESULTS: A total of 1144 children were randomized (C + P: 386; B + P: 381; PA: 377). The mITT analysis set included the 1058 children who attended at least one study visit (C + P: 352; B + P: 352; PA: 354). Median follow-up was 33.8 months (IQR: 23.8, 36.7). The P-CPQ-16 overall score could be calculated after simple imputation at both baseline and final visit for 560 children (C + P: 189; B + P: 189; PA: 182). There was no evidence of a difference in the estimated adjusted mean P-CPQ-16 at the final visit which was, on average, 0.3 points higher (97.5% CI: -1.1 to 1.6) in B + P than C + P and 0.2 points higher, on average, (97.5% CI: -1.2 to 1.5) in PA than for C + P. Child dental trait anxiety and child dental state anxiety, measured at every treatment visit, showed no evidence of any statistically or clinically significant difference between arms in adjusted mean scores averaged over all follow-up visits. CONCLUSIONS: The differences noted in COHRQOL and child-based dental trait and dental state anxiety measures across three treatment strategies for managing dental caries in primary teeth were small, and not considered to be clinically meaningful. The findings highlight the importance of including all three strategies in a clinician's armamentarium, to manage childhood caries throughout the young child's life and achieve positive experiences of dental care.

Dental professionals' experiences of managing children with carious lesions in their primary teeth - a qualitative study within the FiCTION randomised controlled trial.

BACKGROUND: The lack of evidence for the effective management of carious lesions in children's primary teeth has caused uncertainty for the dental profession and patients. Possible approaches include conventional and biological management alongside best practice prevention, and best practice prevention alone. The FiCTION trial assessed the effectiveness of these options, and included a qualitative study exploring dental professionals' (DPs) experiences of delivering the different treatment arms. This paper reports on how DPs managed children with carious lesions within FiCTION and how this related to their everyday experiences of doing dentistry. METHODS: Overall, 31 DPs from FiCTION-trained dental surgeries in four regions of the UK participated in semi-structured interviews about their experiences of the three treatment arms (conventional management of carious lesions and prevention (C + P), biological management of carious lesions and prevention (B + P) or prevention alone (PA)). A theoretical framework, drawing on social practice theory (SPT), was developed for analysis. RESULTS: Participants discussed perceived effectiveness of, and familiarity with, the three techniques. The C + P arm was familiar, but some participants questioned the effectiveness of conventional restorations. Attitudes towards the B + P arm varied in terms of familiarity, but once DPs were introduced to the techniques, this was seen as effective. While prevention was familiar, PA was described as ineffective. DPs manage children with carious lesions day-to-day, drawing on previous experience and knowledge of the child to provide what they view as the most appropriate treatment in the best interests of each child. Randomisation undermined these normal choices. Several DPs reported deviating from the trial arms in order to treat a patient in a particular way. Participants valued evidence-based dentistry, and expect to use the results of FiCTION to inform future practice. They anticipate continuing to use the full range of treatment options, and to personally select appropriate strategies for individual children. CONCLUSIONS: RCTs take place in the context of day-to-day practices of doing dentistry. DPs employ experiential and interpersonal knowledge to act in the best interests of their patients. Randomisation within a clinical trial can present a source of tension for DPs, which has implications for assuring individual equipoise in future trials.

Children and parents' perspectives on the acceptability of three management strategies for dental caries in primary teeth within the 'Filling Children's Teeth: Indicated or Not' (FiCTION) randomised controlled trial - a qualitative study.

BACKGROUND: The Filling Children's Teeth: Indicated Or Not? (FiCTION) randomised controlled trial (RCT) aimed to explore the clinical- and cost-effectiveness of managing dental caries in children's primary teeth. The trial compared three management strategies: conventional caries management with best practice prevention (C + P), biological management with best practice prevention (B + P) and best practice prevention alone (PA)-based approaches. Recently, the concept of treatment acceptability has gained attention and attempts have been made to provide a conceptual definition, however this has mainly focused on adults. Recognising the importance of evaluating the acceptability of interventions in addition to their effectiveness, particularly for multi-component complex interventions, the trial design included a qualitative component. The aim of this component was to explore the acceptability of the three strategies from the perspectives of the child participants and their parents. METHODS: Qualitative exploration, based on the concept of acceptability. Participants were children already taking part in the FiCTION trial and their parents. Children were identified through purposive maximum variation sampling. The sample included children from the three management strategy arms who had been treated and followed up; median (IQR) follow-up was at 33.8 (23.8, 36.7) months. Semi-structured interviews with thirteen child-parent dyads. Interviews were transcribed verbatim and analysed using a framework approach. RESULTS: Data saturation was reached after thirteen interviews. Each child-parent dyad took part in one interview together. The participants were eight girls and five boys aged 5-11 years and their parents. The children's distribution across the trial arms was: C + P n = 4; B + P n = 5; PA n = 4. Three key factors influenced the acceptability of caries management in primary teeth to children and parents: i) experiences of specific procedures within management strategies; ii) experiences of anticipatory dental anxiety and; iii) perceptions of effectiveness (particularly whether pain was reduced). These factors were underpinned by a fourth key factor: the notion of trust in the dental professionals - this was pervasive across all arms. CONCLUSIONS: Overall children and parents found each of the three strategies for the management of dental caries in primary teeth acceptable, with trust in the dental professional playing an important role.

Cost-effectiveness of child caries management: a randomised controlled trial (FiCTION trial).

BACKGROUND: A three-arm parallel group, randomised controlled trial set in general dental practices in England, Scotland, and Wales was undertaken to evaluate three strategies to manage dental caries in primary teeth. Children, with at least one primary molar with caries into dentine, were randomised to receive Conventional with best practice prevention (C + P), Biological with best practice prevention (B + P), or best practice Prevention Alone (PA). METHODS: Data on costs were collected via case report forms completed by clinical staff at every visit. The co-primary outcomes were incidence of, and number of episodes of, dental pain and/or infection avoided. The three strategies were ranked in order of mean cost and a more costly strategy was compared with a less costly strategy in terms of incremental cost-effectiveness. Costs and outcomes were discounted at 3.5%. RESULTS: A total of 1144 children were randomised with data on 1058 children (C + P n = 352, B + P n = 352, PA n = 354) used in the analysis. On average, it costs £230 to manage dental caries in primary teeth over a period of up to 36 months. Managing children in PA was, on average, £19 (97.5% CI: -£18 to £55) less costly than managing those in B + P. In terms of effectiveness, on average, there were fewer incidences of, (- 0.06; 97.5% CI: - 0.14 to 0.02) and fewer episodes of dental pain and/or infection (- 0.14; 97.5% CI: - 0.29 to 0.71) in B + P compared to PA. C + P was unlikely to be considered cost-effective, as it was more costly and less effective than B + P. CONCLUSIONS: The mean cost of a child avoiding any dental pain and/or infection (incidence) was £330 and the mean cost per episode of dental pain and/or infection avoided was £130. At these thresholds B + P has the highest probability of being considered cost-effective. Over the willingness to pay thresholds considered, the probability of B + P being considered cost-effective never exceeded 75%. TRIAL REGISTRATION: The trial was prospectively registered with the ISRCTN (reference number ISRCTN77044005) on the 26th January 2009 and East of Scotland Research Ethics Committee provided ethical approved (REC reference: 12/ES/0047).

7T MRI Predicts Amelioration of Neurodegeneration in the Brain after AAV Gene Therapy.

GM1 gangliosidosis (GM1) is a fatal neurodegenerative lysosomal storage disease that occurs most commonly in young children, with no effective treatment available. Long-term follow-up of GM1 cats treated by bilateral thalamic and deep cerebellar nuclei (DCN) injection of adeno-associated virus (AAV)-mediated gene therapy has increased lifespan to 8 years of age, compared with an untreated lifespan of ~8 months. Due to risks associated with cerebellar injection in humans, the lateral ventricle was tested as a replacement route to deliver an AAVrh8 vector expressing feline ß-galactosidase (ß-gal), the defective enzyme in GM1. Treatment via the thalamus and lateral ventricle corrected storage, myelination, astrogliosis, and neuronal morphology in areas where ß-gal was effectively delivered. Oligodendrocyte number increased, but only in areas where myelination was corrected. Reduced AAV and ß-gal distribution were noted in the cerebellum with subsequent increases in storage, demyelination, astrogliosis, and neuronal degeneration. These postmortem findings were correlated with endpoint MRI and magnetic resonance spectroscopy (MRS). Compared with the moderate dose with which most cats were treated, a higher AAV dose produced superior survival, currently 6.5 years. Thus, MRI and MRS can predict therapeutic efficacy of AAV gene therapy and non-invasively monitor cellular events within the GM1 brain.

Best-practice prevention alone or with conventional or biological caries management for 3- to 7-year-olds: the FiCTION three-arm RCT.

BACKGROUND: Historically, lack of evidence for effective management of decay in primary teeth has caused uncertainty, but there is emerging evidence to support alternative strategies to conventional fillings, which are minimally invasive and prevention orientated. OBJECTIVES: The objectives were (1) to assess the clinical effectiveness and cost-effectiveness of three strategies for managing caries in primary teeth and (2) to assess quality of life, dental anxiety, the acceptability and experiences of children, parents and dental professionals, and caries development and/or progression. DESIGN: This was a multicentre, three-arm parallel-group, participant-randomised controlled trial. Allocation concealment was achieved by use of a centralised web-based randomisation facility hosted by Newcastle Clinical Trials Unit. SETTING: This trial was set in primary dental care in Scotland, England and Wales. PARTICIPANTS: Participants were NHS patients aged 3-7 years who were at a high risk of tooth decay and had at least one primary molar tooth with decay into dentine, but no pain/sepsis. INTERVENTIONS: Three interventions were employed: (1) conventional with best-practice prevention (local anaesthetic, carious tissue removal, filling placement), (2) biological with best-practice prevention (sealing-in decay, selective carious tissue removal and fissure sealants) and (3) best-practice prevention alone (dietary and toothbrushing advice, topical fluoride and fissure sealing of permanent teeth). MAIN OUTCOME MEASURES: The clinical effectiveness outcomes were the proportion of children with at least one episode (incidence) and the number of episodes, for each child, of dental pain or dental sepsis or both over the follow-up period. The cost-effectiveness outcomes were the cost per incidence of, and cost per episode of, dental pain and/or dental sepsis avoided over the follow-up period. RESULTS: A total of 72 dental practices were recruited and 1144 participants were randomised (conventional arm, n = 386; biological arm, n = 381; prevention alone arm, n = 377). Of these, 1058 were included in an intention-to-treat analysis (conventional arm, n = 352; biological arm, n = 352; prevention alone arm, n = 354). The median follow-up time was 33.8 months (interquartile range 23.8-36.7 months). The proportion of children with at least one episode of pain or sepsis or both was 42% (conventional arm), 40% (biological arm) and 45% (prevention alone arm). There was no evidence of a difference in incidence or episodes of pain/sepsis between arms. When comparing the biological arm with the conventional arm, the risk difference was -0.02 (97.5% confidence interval -0.10 to 0.06), which indicates, on average, a 2% reduced risk of dental pain and/or dental sepsis in the biological arm compared with the conventional arm. Comparing the prevention alone arm with the conventional arm, the risk difference was 0.04 (97.5% confidence interval -0.04 to 0.12), which indicates, on average, a 4% increased risk of dental pain and/or dental sepsis in the prevention alone arm compared with the conventional arm. Compared with the conventional arm, there was no evidence of a difference in episodes of pain/sepsis among children in the biological arm (incident rate ratio 0.95, 97.5% confidence interval 0.75 to 1.21, which indicates that there were slightly fewer episodes, on average, in the biological arm than the conventional arm) or in the prevention alone arm (incident rate ratio 1.18, 97.5% confidence interval 0.94 to 1.48, which indicates that there were slightly more episodes in the prevention alone arm than the conventional arm). Over the willingness-to-pay values considered, the probability of the biological treatment approach being considered cost-effective was approximately no higher than 60% to avoid an incidence of dental pain and/or dental sepsis and no higher than 70% to avoid an episode of pain/sepsis. CONCLUSIONS: There was no evidence of an overall difference between the three treatment approaches for experience of, or number of episodes of, dental pain or dental sepsis or both over the follow-up period. FUTURE WORK: Recommendations for future work include exploring barriers to the use of conventional techniques for carious lesion detection and diagnosis (e.g. radiographs) and developing and evaluating suitable techniques and strategies for use in young children in primary care. TRIAL REGISTRATION: Current Controlled Trials ISRCTN77044005. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 1. See the NIHR Journals Library website for further project information.

WHAT WAS THE QUESTION?: Tooth decay is common; it can lead to pain, days off school for children and days off work for parents and is a financial burden to the NHS. There is uncertainty about the best way of managing decay in young children. This trial aimed to find out whether or not there was a difference in the amount of pain and/or infection suffered by children having their decay treated with one of the following: fillings, having decay sealed in or using preventative treatment alone. Which method represented the best value was also explored. WHAT DID WE DO?: For young children with decay, the Filling Children's Teeth: Indicated Or Not? (FiCTION) trial compared the difference between fillings, sealing in the decay and using preventative treatment alone over 3 years in NHS dental practices in Scotland, England and Wales. We recruited 1144 children aged 3­7 years with one or more holes in their baby back teeth (molars), but without pain/infection, and placed them at random into one of three groups: (1) tooth numbing, removing decay and filling(s) with preventative treatment; (2) sealing in decay with fillings or caps and preventative treatment but no numbing; or (3) preventative treatment alone. WHAT DID WE FIND?: Recruitment was challenging but was achieved. There was no evidence of a difference in children's experience of pain or infection, quality of life or dental anxiety between groups. All three ways of treating decay were acceptable to children, parents and dental professionals. Sealing in with preventative treatment was most likely to be considered the best way of managing children's decay if we are willing to pay a minimum of £130 to avoid an episode of pain or infection. WHAT DOES THIS MEAN?: As there was no evidence of a difference between the three treatment groups in pain/infection experienced, treatment choice should continue to be based on shared decision-making between the child, parent and clinician to agree the best option for the individual child.

A Safe and Reliable Technique for CNS Delivery of AAV Vectors in the Cisterna Magna.

Global gene delivery to the CNS has therapeutic importance for the treatment of neurological disorders that affect the entire CNS. Due to direct contact with the CNS, cerebrospinal fluid (CSF) is an attractive route for CNS gene delivery. A safe and effective route to achieve global gene distribution in the CNS is needed, and administration of genes through the cisterna magna (CM) via a suboccipital puncture results in broad distribution in the brain and spinal cord. However, translation of this technique to clinical practice is challenging due to the risk of serious and potentially fatal complications in patients. Herein, we report development of a gene therapy delivery method to the CM through adaptation of an intravascular microcatheter, which can be safely navigated intrathecally under fluoroscopic guidance. We examined the safety, reproducibility, and distribution/transduction of this method in sheep using a self-complementary adeno-associated virus 9 (scAAV9)-GFP vector. This technique was used to treat two Tay-Sachs disease patients (30 months old and 7 months old) with AAV gene therapy. No adverse effects were observed during infusion or post-treatment. This delivery technique is a safe and minimally invasive alternative to direct infusion into the CM, achieving broad distribution of AAV gene transfer to the CNS.

The use of urinary fluoride excretion to facilitate monitoring fluoride intake: A systematic scoping review.

BACKGROUND: As a recognised effective and economical agent for dental caries prevention, fluoride has been used in many different fluoridation schemes implemented across the world. Considering the narrow 'dose-gap' between the benefit of caries reduction and the risk of dental fluorosis, it is recommended that fluoride intake is monitored by measuring urinary fluoride excretion. The aim of this scoping review is to map the current literature/evidence on fluoride intake and excretion studies in relation to the study population, settings, type of study design, methodology, and analytical approach. METHODS: Embase/Ovid, MEDLINE/Ovid, CINAHL/EBSCO, Scopus/Elsevier were searched for relevant articles until April 2018. Studies were included if they reported intake and excretion of fluoride in healthy humans of all age groups. Findings were explored using a narrative synthesis to summarise studies characteristics and outcome measures. RESULTS: Removal of duplicates from the originally 2295 identified records yielded 1093 studies of which 206 articles were included. Only 21.6% of the studies were conducted in children (<8-year-olds). Most studies (38.8%) used drinking water concentration as a proxy for fluoride intake, whereas only 11.7% measured fluoride intake from all sources. Of the 72 studies that measured dietary fluoride intake, only 10 reported the validity of the employed dietary assessment method. Only 14 studies validated the urine sample collection methods. No information on the validity of the employed analytical method was reported by the majority (64.6%) of studies. Only a small proportion (8.7%) of the included studies investigated the association between fluoride intake and excretion. CONCLUSION: The findings reveal much variability in terms of conducting the studies and reporting the findings, illustrating a high heterogeneity in data collection across settings and populations. Future studies should provide more detail on sampling technique, measurement protocols (including validation), and on clearly defining the relationship between intake and urinary excretion of fluoride.

A Comparison of Simple Analytical Methods for Determination of Fluoride in Microlitre-Volume Plasma Samples.

The aim was to compare potential methods for fluoride analysis in microlitre-volume plasma samples containing nano-gram amounts of fluoride. Methods: A group of 4 laboratories analysed a set of standardised biological samples as well as plasma to determine fluoride concentration using 3 methods. In Phase-1, fluoride analysis was carried out using the established hexamethyldisiloxane (HMDS)-diffusion method (1 mL-aliquot/analysis) to obtain preliminary measurement of agreement between the laboratories. In Phase-2, the laboratories analysed the same samples using a micro-diffusion method and known-addition technique with 200 µL-aliquot/analysis. Coefficients of Variation (CVs) and intra-class correlation coefficients (ICCs) were estimated using analysis of variance to evaluate the amount of variation within- and between-laboratories. Based on the results of the Phase-2 analysis, 20 human plasma samples were analysed and compared using the HMDS-diffusion method and known-addition technique in Phase-3. Results: Comparison of Phase-1 results showed no statistically significant difference among the laboratories for the overall data set. The mean between- and within-laboratory CVs and ICCs were < 0.13 and ≥0.99, respectively, indicating very low variability and excellent reliability. In Phase-2, the overall results for between-laboratory variability showed a poor CV (1.16) and ICC (0.44) for the micro-diffusion method, whereas with the known-addition technique the corresponding values were 0.49 and 0.83. Phase-3 results showed no statistically significant difference in fluoride concentrations of the plasma samples measured with HMDS-diffusion method and known- addition technique, with a mean (SE) difference of 0.002 (0.003) µg/mL. In conclusion, the known-addition technique could be a suitable alternative for the measurement of fluoride in plasma with microlitre-volume samples.

Fluoride retention in infants living in fluoridated and non-fluoridated areas: effects of weaning.

Limited knowledge is available on total fluoride exposure, excretion and retention in infants, despite the first year of human life being the critical period for dental development and risk of dental fluorosis. This study investigated total daily fluoride intake (TDFI), excretion (TDFE) and retention (TDFR) in infants living in fluoridated and non-fluoridated water areas at pre- and post-weaning stages of development. Healthy infants, aged 0-12 months, were recruited and their TDFI (mg/kg body weight (BW) per d), from diet and toothpaste ingestion, was assessed over a 3-d period using a dietary diary and tooth-brushing questionnaire. TDFE (mg/kg BW per d) was estimated by collecting 48-h urine and faeces. TDFR (mg/kg BW per d) was estimated by subtracting TDFE from TDFI. A total of forty-seven infants completed the study: sixteen at pre-weaning and thirty-one at post-weaning stages, with a mean age of 3·4 and 10·0 months, respectively. TDFI was lower in the non-fluoridated area (P<0·001) and at the pre-weaning stage (P=0·002) but higher in formula-fed infants (P<0·001). TDFE was mainly affected by type of feeding, with higher excretion in formula-fed infants (P<0·001). TDFR was lower in the non-fluoridated area (P<0·001) and at the pre-weaning stage (P<0·001) but higher in formula-fed infants (P=0·001). In conclusion, a relatively large proportion of fluoride intake is retained in the body in weaned infants. This is an important consideration in fluoride-based prevention programmes, with goals to maximise caries prevention while minimising the risk of dental fluorosis.

Comparison of total ionic strength adjustment buffers III and IV in the measurement of fluoride concentration of teas.

BACKGROUND: Tea is the second most consumed drink in the UK and a primary source of hydration; it is an important source of dietary fluoride (F) for consumers and also abundant in aluminium (Al). Varying ranges of F concentrations in teas have been reported worldwide which may be, in part, due to differences in analytical techniques used to measure this ion. AIM: The effect of using total ionic adjustment buffers (TISAB) III or IV when measuring F concentration of black teas available in the UK was investigated and compared. Based on this evaluation, the effects of three different infusion times, 1 min, 10 min and 1 h, caffeine content and tea form on the F contents of the tea samples were investigated. METHODS: The F concentrations of 47 tea samples were measured directly using a fluoride ion-selective electrode (F-ISE), TISAB III and IV and infusion times of 1 min, 10 min and 1 h. RESULTS: Mean (SD) F concentration of tea samples for all infusion times was statistically significantly higher ( p < 0.001) measured by TISAB IV (4.37 (2.16) mg/l) compared with TISAB III (3.54 (1.65) mg/l). A statistically significant positive correlation ( p < 0.001) was found between Al concentration (mg/l) and differences in F concentration (mg/l) measured using the two TISABs; the difference in F concentration measured by the two TISABs increased with the magnitude of Al concentration. CONCLUSION: Due to higher concentrations of F and Al in teas and their complexing potential, use of TISAB IV facilitates more accurate measurement of F concentration when using an F-ISE and a direct method.

Effect of chronic exercise on fluoride metabolism in fluorosis-susceptible mice exposed to high fluoride.

The present study investigated the effect of chronic exercise on fluoride (F) metabolism in fluorosis-susceptible mice exposed to high-F and explored the relationship between F concentrations in bone and plasma. Thirty male mice were randomised into three groups: Group I (No-F, No-Exercise), Group II (50 ppmF, No-Exercise), Group III (50 ppmF, Exercise). Body weight and physical performance of all mice were measured at baseline and end of experiment. F concentrations of plasma and bone were measured at the end of experiment. Mean plasma F concentration was significantly higher (p < 0.001) in Groups II and III compared with Group I. Mean bone F concentration was also significantly higher (p < 0.01) in Groups II and III compared with Group I. There was a significant correlation (p = 0.01, r = 0.54) between F concentration of plasma and bone. Mean body weight of Group I mice was significantly higher than Group II (p < 0.001) and Group III (p = 0.001) mice at the end of the experiment. This study, which provides the first data on the effect of chronic exercise on F metabolism in fluorosis-susceptible mice, suggests no effect of chronic exercise on F in plasma and bone. However, exposure to high-F resulted in lower body weight and exercise capacity in mice.