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1.
Dev Med Child Neurol ; 66(7): 863-871, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38385885

ABSTRACT

Fragile X syndrome (FXS) is a neurodevelopmental disorder caused by a full mutation (> 200 CGG repeats) in the FMR1 gene. FXS is the leading cause of inherited intellectual disabilities and the most commonly known genetic cause of autism spectrum disorder. Children with FXS experience behavioral and sleep problems, anxiety, inattention, learning difficulties, and speech and language delays. There are no approved medications for FXS; however, there are several interventions and treatments aimed at managing the symptoms and improving the quality of life of individuals with FXS. A combination of non-pharmacological therapies and pharmacotherapy is currently the most effective treatment for FXS. Currently, several targeted treatments, such as metformin, sertraline, and cannabidiol, can be used by clinicians to treat FXS. Gene therapy is rapidly developing and holds potential as a prospective treatment option. Soon its efficacy and safety in patients with FXS will be demonstrated. WHAT THIS PAPER ADDS: Targeted treatment of fragile X syndrome (FXS) is the best current therapeutic approach. Gene therapy holds potential as a prospective treatment for FXS in the future.


Subject(s)
Fragile X Syndrome , Genetic Therapy , Fragile X Syndrome/therapy , Fragile X Syndrome/genetics , Fragile X Syndrome/drug therapy , Humans , Fragile X Mental Retardation Protein/genetics
2.
Front Pharmacol ; 15: 1326779, 2024.
Article in English | MEDLINE | ID: mdl-38318146

ABSTRACT

The control of parasitic nematode infections relies mostly on anthelmintics. The potential pharmacotherapeutic application of phytochemicals, in order to overcome parasite resistance and enhance the effect of existing drugs, is becoming increasingly important. The antinematodal effects of carveol was tested on the free-living nematode Caenorhabditis elegans and the neuromuscular preparation of the parasitic nematode Ascaris suum. Carveol caused spastic paralysis in C. elegans. In A. suum carveol potentiated contractions induced by acetylcholine (ACh) and this effect was confirmed with two-electrode voltage-clamp electrophysiology on the A. suum nicotinic ACh receptor expressed in Xenopus oocytes. However, potentiating effect of carveol on ACh-induced contractions was partially sensitive to atropine, indicates a dominant nicotine effect but also the involvement of some muscarinic structures. The effects of carveol on the neuromuscular system of mammals are also specific. In micromolar concentrations, carveol acts as a non-competitive ACh antagonist on ileum contractions. Unlike atropine, it does not change the EC50 of ACh, but reduces the amplitude of contractions. Carveol caused an increase in Electrical Field Stimulation-evoked contractions of the isolated rat diaphragm, but at higher concentrations it caused an inhibition. Also, carveol neutralized the mecamylamine-induced tetanic fade, indicating a possibly different pre- and post-synaptic action at the neuromuscular junction.

3.
Cells ; 12(18)2023 09 21.
Article in English | MEDLINE | ID: mdl-37759552

ABSTRACT

The premutation of the fragile X messenger ribonucleoprotein 1 (FMR1) gene is characterized by an expansion of the CGG trinucleotide repeats (55 to 200 CGGs) in the 5' untranslated region and increased levels of FMR1 mRNA. Molecular mechanisms leading to fragile X-premutation-associated conditions (FXPAC) include cotranscriptional R-loop formations, FMR1 mRNA toxicity through both RNA gelation into nuclear foci and sequestration of various CGG-repeat-binding proteins, and the repeat-associated non-AUG (RAN)-initiated translation of potentially toxic proteins. Such molecular mechanisms contribute to subsequent consequences, including mitochondrial dysfunction and neuronal death. Clinically, premutation carriers may exhibit a wide range of symptoms and phenotypes. Any of the problems associated with the premutation can appropriately be called FXPAC. Fragile X-associated tremor/ataxia syndrome (FXTAS), fragile X-associated primary ovarian insufficiency (FXPOI), and fragile X-associated neuropsychiatric disorders (FXAND) can fall under FXPAC. Understanding the molecular and clinical aspects of the premutation of the FMR1 gene is crucial for the accurate diagnosis, genetic counseling, and appropriate management of affected individuals and families. This paper summarizes all the known problems associated with the premutation and documents the presentations and discussions that occurred at the International Premutation Conference, which took place in New Zealand in 2023.


Subject(s)
Fragile X Mental Retardation Protein , Fragile X Syndrome , Humans , Fragile X Mental Retardation Protein/genetics , Fragile X Mental Retardation Protein/metabolism , Mutation/genetics , RNA, Messenger/metabolism , Trinucleotide Repeat Expansion/genetics , Fragile X Syndrome/diagnosis , Fragile X Syndrome/genetics , Fragile X Syndrome/therapy
4.
Cells ; 12(13)2023 06 24.
Article in English | MEDLINE | ID: mdl-37443745

ABSTRACT

Carriers of the FMR1 premutation (PM) allele are at risk of one or more clinical conditions referred to as FX premutation-associated conditions (FXPAC). Since the FMR1 gene is on the X chromosome, the activation ratio (AR) may impact the risk, age of onset, progression, and severity of these conditions. The aim of this study was to evaluate the reliability of AR measured using different approaches and to investigate potential correlations with clinical outcomes. Molecular and clinical assessments were obtained for 30 PM female participants, and AR was assessed using both Southern blot analysis (AR-Sb) and methylation PCR (AR-mPCR). Higher ARs were associated with lower FMR1 transcript levels for any given repeat length. The higher AR-Sb was significantly associated with performance, verbal, and full-scale IQ scores, confirming previous reports. However, the AR-mPCR was not significantly associated (p > 0.05) with these measures. Similarly, the odds of depression and the number of medical conditions were correlated with higher AR-Sb but not correlated with a higher AR-mPCR. This study suggests that AR-Sb may be a more reliable measure of the AR in female carriers of PM alleles. However, further studies are warranted in a larger sample size to fully evaluate the methylation status in these participants and how it may affect the clinical phenotype.


Subject(s)
Fragile X Mental Retardation Protein , Female , Animals , Fragile X Mental Retardation Protein/genetics , Fragile X Mental Retardation Protein/metabolism , Reproducibility of Results , Heterozygote , Methylation , Alleles
5.
Genes (Basel) ; 13(12)2022 12 17.
Article in English | MEDLINE | ID: mdl-36553666

ABSTRACT

Background: The fragile X premutation carrier state (PM) (55-200 CGG repeats in the fragile X messenger ribonucleoprotein 1, FMR1 gene) is associated with several conditions, including fragile X-associated primary ovarian insufficiency (FXPOI) and fragile X-associated tremor ataxia (FXTAS), with current literature largely primarily investigating older PM individuals. The aim of this study was to identify the prevalence of fragile X-associated neurodevelopmental disorders (FXAND) in a sample of young PM individuals. Methods: This was a retrospective study conducted through a medical record review of PM individuals who were seen either for clinical concerns (probands, 45.9%) or identified through the cascade testing (non-probands, 54.1%) of an affected sibling with fragile X syndrome. Information on the presence of autism spectrum disorder, attention deficit hyperactivity disorder, anxiety, depression, long-term psychiatric medication intake, and cognitive function, based on standardized assessments, was obtained. Molecular data, including CGG repeat number and FMR1 mRNA levels, were also available for a subset of participants. Analysis included descriptive statistics and a test of comparison to describe the clinical profile of PM individuals pertinent to FXAND. Results: Participants included 61 individuals (52 males and 9 females) aged 7.8 to 20.0 years (mean 12.6 ± 3.4) with a mean full-scale IQ of 90.9 ± 22.7. The majority (N = 52; 85.2%) had at least one mental health disorder, with anxiety being the most common (82.0% of subjects), followed by ADHD (66.5%), and ASD (32.8%). Twenty-seven (87.1%) of non-probands also had at least one mental health condition, with probands having lower cognitive and adaptive skills than non-probands. ASD was present in 20 participants (17/52 males and 3/9 females; 15 probands) with significantly lower FSIQ in those with ASD (mean 73.5 vs. 98.0, p < 0.001). Participants with ASD had a higher number of long-term medications compared to those without (2.32 vs. 1.3, p = 0.002). Conclusions: Our findings indicate a high rate of FXAND diagnoses within a cohort of young PM individuals, including those identified via cascade testing, although this was not a population sample. An awareness of the entity of FXAND and the early recognition of the symptoms of associated conditions may facilitate timely and appropriate care for PM individuals.


Subject(s)
Autism Spectrum Disorder , Fragile X Syndrome , Male , Female , Humans , Autism Spectrum Disorder/genetics , Retrospective Studies , Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/genetics , Tremor/genetics
6.
Brain Sci ; 12(10)2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36291209

ABSTRACT

This Brain Sciences 2020 Special Issue of nine manuscripts contribute novel data on treatment updates in fragile X syndrome (FXS) [...].

7.
J Neurol ; 269(9): 4676-4683, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35723724

ABSTRACT

There is increasing recognition of the heterogeneity of origin of cases of autism spectrum disorder (ASD) with multiple forms of ASD having been identified over the decades. Among these, a genetic etiology can be identified in 20-40% of cases when a full genetic work-up is completed. The Fragile X premutation state (characterized by the presence of 55-200 CGG repeats in the FMR1 gene) is a relatively newly identified disease state that has since been associated with several disorders including fragile X-associated tremor ataxia syndrome (FXTAS), fragile X-associated primary ovarian insufficiency (FXPOI) and most recently, fragile X-associated neurodevelopmental disorders (FXAND) which commonly includes anxiety and depression. In addition to these associated disorders, extant literature and clinical observations have suggested an association between the premutation state and ASD. In this paper, we review the literature pertinent to this and discuss possible molecular mechanisms that may explain this association. This includes lowered levels of the FMR1 Protein (FMRP), GABA deficits, mitochondrial dysfunction and secondary genetic abnormalities that is seen in premutation carriers as well as their increased vulnerability to environmental stressors. Understanding these mechanisms can facilitate development of targeted treatment for specific sub-groups of ASD and premutation disorders in future.


Subject(s)
Autism Spectrum Disorder , Fragile X Syndrome , Ataxia/genetics , Autism Spectrum Disorder/genetics , Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/complications , Fragile X Syndrome/genetics , Humans , Mutation/genetics
8.
Int J Mol Sci ; 23(4)2022 Feb 09.
Article in English | MEDLINE | ID: mdl-35216055

ABSTRACT

Fragile X syndrome (FXS) is a neurodevelopmental disorder caused by the full mutation as well as highly localized methylation of the fragile X mental retardation 1 (FMR1) gene on the long arm of the X chromosome. Children with FXS are commonly co-diagnosed with Autism Spectrum Disorder, attention and learning problems, anxiety, aggressive behavior and sleep disorder, and early interventions have improved many behavior symptoms associated with FXS. In this review, we performed a literature search of original and review articles data of clinical trials and book chapters using MEDLINE (1990-2021) and ClinicalTrials.gov. While we have reviewed the biological importance of the fragile X mental retardation protein (FMRP), the FXS phenotype, and current diagnosis techniques, the emphasis of this review is on clinical interventions. Early non-pharmacological interventions in combination with pharmacotherapy and targeted treatments aiming to reverse dysregulated brain pathways are the mainstream of treatment in FXS. Overall, early diagnosis and interventions are fundamental to achieve optimal clinical outcomes in FXS.


Subject(s)
Fragile X Syndrome/genetics , Animals , Brain/pathology , Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/pathology , Humans , Phenotype
9.
Am J Med Genet A ; 188(4): 1029-1039, 2022 04.
Article in English | MEDLINE | ID: mdl-34889523

ABSTRACT

Fragile X syndrome (FXS), the leading cause of inherited intellectual disability and autism spectrum disorder, is associated with multiple neurobehavioral abnormalities including sleep difficulties. Nonetheless, frequency, severity, and consequences of sleep problems are still unclear. The Fragile X Online Registry with Accessible Research Database (FORWARD-version-3), including Clinician Report and Parent Report forms, was analyzed for frequency, severity, relationship with behavioral problems, and impact of sleep difficulties in a mainly pediatric cohort. A focused evaluation of sleep apnea was also conducted. Six surveyed sleep difficulties were moderately frequent (~23%-46%), relatively mild, affected predominantly younger males, and considered a problem for 7%-20% of families. Snoring was more prevalent in older individuals. All sleep difficulties were associated with irritability/aggression and most also to hyperactivity. Only severe snoring was correlated with sleep apnea (loud snoring: 30%; sleep apnea: 2%-3%). Sleep difficulties are prevalent in children with FXS and, although they tend to be mild, they are associated with behavioral problems and negative impact to families. Because of its cross-sectional nature, clinic-origin, use of ad hoc data collection forms, and lack of treatment data, the present study should be considered foundational for future research aiming at better recognition and management of sleep problems in FXS.


Subject(s)
Autism Spectrum Disorder , Fragile X Syndrome , Sleep Apnea Syndromes , Aged , Autism Spectrum Disorder/complications , Autism Spectrum Disorder/epidemiology , Autism Spectrum Disorder/genetics , Child , Cross-Sectional Studies , Fragile X Syndrome/complications , Fragile X Syndrome/epidemiology , Fragile X Syndrome/genetics , Humans , Male , Sleep Apnea Syndromes/complications , Sleep Apnea Syndromes/epidemiology , Snoring/complications , Snoring/epidemiology
10.
Genes (Basel) ; 14(1)2022 12 28.
Article in English | MEDLINE | ID: mdl-36672829

ABSTRACT

Fragile X syndrome (FXS) is a global neurodevelopmental disorder caused by the expansion of CGG trinucleotide repeats (≥200) in the Fragile X Messenger Ribonucleoprotein 1 (FMR1) gene. FXS is the hallmark of Fragile X-associated disorders (FXD) and the most common monogenic cause of inherited intellectual disability and autism spectrum disorder. There are several animal models used to study FXS. In the FXS model of Drosophila, the only ortholog of FMR1, dfmr1, is mutated so that its protein is missing. This model has several relevant phenotypes, including defects in the circadian output pathway, sleep problems, memory deficits in the conditioned courtship and olfactory conditioning paradigms, deficits in social interaction, and deficits in neuronal development. In addition to FXS, a model of another FXD, Fragile X-associated tremor/ataxia syndrome (FXTAS), has also been established in Drosophila. This review summarizes many years of research on FXD in Drosophila models.


Subject(s)
Autism Spectrum Disorder , Drosophila Proteins , Fragile X Syndrome , Animals , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Fragile X Syndrome/genetics , Ataxia/genetics , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Fragile X Mental Retardation Protein/genetics , Fragile X Mental Retardation Protein/metabolism
11.
Yale J Biol Med ; 94(4): 559-571, 2021 12.
Article in English | MEDLINE | ID: mdl-34970093

ABSTRACT

Fragile X syndrome is the most common monogenetic cause of inherited intellectual disability and syndromic autism spectrum disorder. Fragile X syndrome is caused by an expansion (full mutation ≥200 CGGs repeats, normal 10-45 CGGs) of the fragile X mental retardation 1 (FMR1) gene, epigenetic silencing of the gene, which leads to reduction or lack of the gene's product: the fragile X mental retardation protein. In this cross-sectional study, we assessed general and pharmacotherapy knowledge (GK and PTK) of fragile X syndrome and satisfaction with education in neurodevelopmental disorders (NDDs) among senior medical students in Serbia (N=348), Georgia (N=112), and Colombia (N=58). A self-administered 18-item questionnaire included GK (8/18) and PTK (7/18) components and self-assessment of the participants education in NDDs (3/18). Roughly 1 in 5 respondents had correct answers on half or more facts about fragile X syndrome (GK>PTK), which ranged similarly 5-7 in Serbia, 6-8 in Georgia, and 5-8 in Colombia, respectively. No cohort had an average value greater than 9 (60%) that would represent passing score "cut-off." None of the participants answered all the questions correctly. More than two-thirds of the participants concluded that they gained inadequate knowledge of NDDs during their studies, and that their education in this field should be more intense. In conclusion, there is a major gap in knowledge regarding fragile X syndrome among senior medical students in these three developing countries. The finding could at least in part be generalized to other developing countries aimed toward increasing knowledge and awareness of NDDs and fostering an institutional collaboration between developed and developing countries.


Subject(s)
Fragile X Syndrome , Autism Spectrum Disorder , Colombia/epidemiology , Cross-Sectional Studies , Developing Countries , Fragile X Mental Retardation Protein , Fragile X Syndrome/epidemiology , Fragile X Syndrome/genetics , Georgia (Republic)/epidemiology , Humans , Mutation , Serbia/epidemiology
12.
Brain Sci ; 10(10)2020 Sep 30.
Article in English | MEDLINE | ID: mdl-33008014

ABSTRACT

Fragile X syndrome (FXS) is caused by silencing of the FMR1 gene, which encodes a protein with a critical role in synaptic plasticity. The molecular abnormality underlying FMR1 silencing, CGG repeat expansion, is well characterized; however, delineation of the pathway from DNA to RNA to protein using biosamples from well characterized patients with FXS is limited. Since FXS is a common and prototypical genetic disorder associated with intellectual disability (ID) and autism spectrum disorder (ASD), a comprehensive assessment of the FMR1 DNA-RNA-protein pathway and its correlations with the neurobehavioral phenotype is a priority. We applied nine sensitive and quantitative assays evaluating FMR1 DNA, RNA, and FMRP parameters to a reference set of cell lines representing the range of FMR1 expansions. We then used the most informative of these assays on blood and buccal specimens from cohorts of patients with different FMR1 expansions, with emphasis on those with FXS (N = 42 total, N = 31 with FMRP measurements). The group with FMRP data was also evaluated comprehensively in terms of its neurobehavioral profile, which allowed molecular-neurobehavioral correlations. FMR1 CGG repeat expansions, methylation levels, and FMRP levels, in both cell lines and blood samples, were consistent with findings of previous FMR1 genomic and protein studies. They also demonstrated a high level of agreement between blood and buccal specimens. These assays further corroborated previous reports of the relatively high prevalence of methylation mosaicism (slightly over 50% of the samples). Molecular-neurobehavioral correlations confirmed the inverse relationship between overall severity of the FXS phenotype and decrease in FMRP levels (N = 26 males, mean 4.2 ± 3.3 pg FMRP/ng genomic DNA). Other intriguing findings included a significant relationship between the diagnosis of FXS with ASD and two-fold lower levels of FMRP (mean 2.8 ± 1.3 pg FMRP/ng genomic DNA, p = 0.04), in particular observed in younger age- and IQ-adjusted males (mean age 6.9 ± 0.9 years with mean 3.2 ± 1.2 pg FMRP/ng genomic DNA, 57% with severe ASD), compared to FXS without ASD. Those with severe ID had even lower FMRP levels independent of ASD status in the male-only subset. The results underscore the link between FMR1 expansion, gene methylation, and FMRP deficit. The association between FMRP deficiency and overall severity of the neurobehavioral phenotype invites follow up studies in larger patient cohorts. They would be valuable to confirm and potentially extend our initial findings of the relationship between ASD and other neurobehavioral features and the magnitude of FMRP deficit. Molecular profiling of individuals with FXS may have important implications in research and clinical practice.

13.
Clin Interv Aging ; 15: 285-292, 2020.
Article in English | MEDLINE | ID: mdl-32161452

ABSTRACT

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder that usually begins in the early 60s and affects carriers of premutation expansion (55-200 CGG repeats) of the fragile X mental retardation 1 (FMR1) gene. Additional disorders can co-occur with FXTAS including Alzheimer's disease (AD). Here we discuss a case report of a male with 67 CGG repeats in FMR1 who had mild late-onset FXTAS symptoms followed by neurocognitive disorder symptoms consistent with AD. The patient has developed tremor and ataxia that are the two characteristic symptoms of FXTAS. In addition, he shows rapid cognitive decline, brain atrophy most substantial in the medial temporal lobe, and decreased metabolism in the brain regions that are the characteristic findings of AD. The purpose of this study is to describe a patient profile with both diseases and review the details of an overlap between these two diseases.


Subject(s)
Alzheimer Disease/complications , Alzheimer Disease/metabolism , Ataxia/diagnosis , Ataxia/metabolism , Fragile X Syndrome/diagnosis , Fragile X Syndrome/metabolism , Tremor/diagnosis , Tremor/metabolism , Aged , Ataxia/complications , Fragile X Mental Retardation Protein/metabolism , Fragile X Syndrome/complications , Humans , Male , Middle Aged , Tremor/complications
14.
Curr Pediatr Rev ; 15(4): 251-258, 2019.
Article in English | MEDLINE | ID: mdl-31241016

ABSTRACT

Fragile X Syndrome (FXS) is the most common cause of inherited intellectual disability with prevalence rates estimated to be 1:5,000 in males and 1:8,000 in females. The increase of >200 Cytosine Guanine Guanine (CGG) repeats in the 5' untranslated region of the Fragile X Mental Retardation 1 (FMR1) gene results in transcriptional silencing on the FMR1 gene with a subsequent reduction or absence of fragile X mental retardation protein (FMRP), an RNA binding protein involved in the maturation and elimination of synapses. In addition to intellectual disability, common features of FXS are behavioral problems, autism, language deficits and atypical physical features. There are still no currently approved curative therapies for FXS, and clinical management continues to focus on symptomatic treatment of comorbid behaviors and psychiatric problems. Here we discuss several treatments that target the neurobiological pathway abnormal in FXS. These medications are clinically available at present and the data suggest that these medications can be helpful for those with FXS.


Subject(s)
Fragile X Syndrome/drug therapy , GABA Agonists/pharmacology , Gene Expression Regulation/drug effects , Gene Silencing/drug effects , Molecular Targeted Therapy , Selective Serotonin Reuptake Inhibitors/pharmacology , Animals , Cellular Reprogramming/genetics , Child , DNA Methylation , Disease Models, Animal , Epigenesis, Genetic , Fragile X Mental Retardation Protein , Fragile X Syndrome/genetics , Fragile X Syndrome/physiopathology , Humans , Molecular Targeted Therapy/trends , Signal Transduction , Treatment Outcome
15.
Mol Genet Genomic Med ; 7(7): e00745, 2019 07.
Article in English | MEDLINE | ID: mdl-31104364

ABSTRACT

BACKGROUND: The majority of individuals with fragile X syndrome (FXS) have intellectual disability, behavioral problems, autism, and language deficits. IQ typically declines with age in boys with the full mutation. The results of preclinical studies demonstrated that metformin, a biguanide used to treat type 2 diabetes, rescues multiple phenotypes of FXS in both Drosophila and mouse models. Preliminary studies of patients with FXS demonstrated improvements in behavior. METHODS: Here, we present two cases of individuals who have been treated with metformin clinically for one year. RESULTS: Both patients demonstrated significant cognitive and behavioral improvements. They also improved eating habits and normalization of their weight percentiles. CONCLUSION: Metformin may be a candidate drug for treatment of several types of symptoms in individuals with FXS.


Subject(s)
Cognition/drug effects , Fragile X Syndrome/drug therapy , Metformin/pharmacology , Adult , Humans , Intelligence Tests , Male
16.
PLoS One ; 14(12): e0226811, 2019.
Article in English | MEDLINE | ID: mdl-31891607

ABSTRACT

Fragile X syndrome, the leading heritable form of intellectual disability, is caused by hypermethylation and transcriptional silencing of large (CGG) repeat expansions (> 200 repeats) in the 5' untranslated region of the fragile X mental retardation 1 (FMR1) gene. As a consequence of FMR1 gene silencing, there is little or no production of FMR1 protein (FMRP), an important element in normal synaptic function. Although the absence of FMRP has long been known to be responsible for the cognitive impairment in fragile X syndrome, the relationship between FMRP level and cognitive ability (IQ) is only imprecisely understood. To address this issue, a high-throughput, fluorescence resonance energy transfer (FRET) assay has been used to quantify FMRP levels in dermal fibroblasts, and the relationship between FMRP and IQ measures was assessed by statistical analysis in a cohort of 184 individuals with CGG-repeat lengths spanning normal (< 45 CGGs) to full mutation (> 200 CGGs) repeat ranges in fibroblasts. The principal findings of the current study are twofold: i) For those with normal CGG repeats, IQ is no longer sensitive to further increases in FMRP above an FMRP threshold of ~70% of the mean FMRP level; below this threshold, IQ decreases steeply with further decreases in FMRP; and ii) For the current cohort, a mean IQ of 85 (lower bound for the normal IQ range) is attained for FMRP levels that are only ~35% of the mean FMRP level among normal CGG-repeat controls. The current results should help guide expectations for efforts to induce FMR1 gene activity and for the levels of cognitive function expected for a given range of FMRP levels.


Subject(s)
Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/genetics , Intelligence/genetics , Trinucleotide Repeat Expansion/genetics , Adolescent , Adult , Aged , Child , Cognition , Cohort Studies , Female , Fibroblasts , Gene Silencing , Humans , Male , Middle Aged , Wechsler Scales , Young Adult
17.
Front Psychiatry ; 9: 564, 2018.
Article in English | MEDLINE | ID: mdl-30483160

ABSTRACT

Fragile X syndrome (FXS) is caused by the full mutation (>200 CGG repeats) in the Fragile X Mental Retardation 1 (FMR1) gene. It is the most common inherited cause of intellectual disability (ID) and autism. This review focuses on neuropsychiatric disorders frequently experienced by premutation carriers with 55 to 200 CGG repeats and the pathophysiology involves elevated FMR1 mRNA levels, which is different from the absence or deficiency of fragile X mental retardation protein (FMRP) seen in FXS. Neuropsychiatric disorders are the most common problems associated with the premutation, and they affect approximately 50% of individuals with 55 to 200 CGG repeats in the FMR1 gene. Neuropsychiatric disorders in children with the premutation include anxiety, ADHD, social deficits, or autism spectrum disorders (ASD). In adults with the premutation, anxiety and depression are the most common problems, although obsessive compulsive disorder, ADHD, and substance abuse are also common. These problems are often exacerbated by chronic fatigue, chronic pain, fibromyalgia, autoimmune disorders and sleep problems, which are also associated with the premutation. Here we review the clinical studies, neuropathology and molecular underpinnings of RNA toxicity associated with the premutation. We also propose the name Fragile X-associated Neuropsychiatric Disorders (FXAND) in an effort to promote research and the use of fragile X DNA testing to enhance recognition and treatment for these disorders.

18.
Front Neurosci ; 12: 652, 2018.
Article in English | MEDLINE | ID: mdl-30297982

ABSTRACT

We conducted a knowledge, attitude, and practice (KAP) survey of fragile X-associated disorders (FXD) in Serbia in order to obtain baseline quantitative and qualitative KAP data on fragile X mental retardation 1 gene (FMR1) pre- and full mutations (PM, FM). The survey's 16-item questionnaire included a knowledge component (12/16), such as self-assessment knowledge (SAK) and factual knowledge (FK, 2/5 questions for PM, FXTAS and FXPOI). Education-directed attitudes in the FXD field and FMR1 DNA testing practices had 4/16 items, including brief case vignettes of FXTAS and FXPOI, respectively. The study's cohort consisted of primary care physicians (referred to as "physicians" in the rest of the text) throughout Serbia (n = 284, aged 26-64 years, 176/284, 62.2% in Belgrade, Serbia) and senior medical students (n = 245, aged 23-30 years; 33.5% males) at the Belgrade School of Medicine. Strikingly, half of the survey respondents indicated "not having any" knowledge for the fragile X gene premutation and FXD. Physicians were more likely to indicate "not having any" knowledge than students (41.2% of physicians vs. 13.1% of students, P < 0.05). Roughly half of the students had "minimal knowledge" (53.5 vs. 30.5% of physicians, P < 0.05). Low FK was common in the cohort, as few physicians had "all correct answers" (7.5 vs. 3.7% of students, P < 0.05; 16.5 vs. 9.5% of students for the 2/5 premutation-related questions). Statistical analyses identified physicians' practice setting and length of clinical experience as predictors of the lack of FK on questions related to FXD. Physicians were more likely than students to indicate "strongly agreed" to expand their knowledge of the gene premutation and FXD (90.9 vs. 66.7% of students, P < 0.01). However, students more frequently indicated that they are willing to recommend DNA testing in their future practices than physicians (93.5 vs. 64.8% of physicians, P < 0.001). In conclusion, there is a major gap in knowledge regarding fragile X gene PM and FXD among the study's participants in Serbia. The study's informative-educational survey serves as an initial step in the process of enhancing the KAP of medical professionals with regards to the fragile X gene premutation and FXD.

19.
Zdr Varst ; 56(3): 179-184, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28713447

ABSTRACT

INTRODUCTION: Medical students are mainly exposed to needle stick and sharp object injuries in the course of their clinical activities during studying. They are at high risk due to their undeveloped skills, restricted clinical experience, lack of knowledge and risk perception. The objectives of this study were to determine the prevalence of needle stick injuries of the fourth and final year medical students, and to estimate their knowledge about blood-borne pathogens disease transmission and standard precautions. METHODS: This cross-sectional study was conducted at the Faculty of Medicine, in February 2014. The students were invited to self-administer a questionnaire of 26 closed questions prepared for this study. RESULTS: The questionnaire was filled in and returned by 637 students. The prevalence of needle sticks and sharp object injuries was 29.5%. Needle stick injuries were the most common type of accidents, more frequent among the fourth compared to the sixth year students (p=0.002). The majority of accidents occurred in patient rooms (53%) and the emergency department (15%). 54% of participants reported an accident to the responsible person. Students without accidents had a significantly better perception of risk (3.79 vs. 3.35; p<0.05). Out of the total participating students, only 16.6% (106/637) received all three doses of Hepatitis B vaccination, while 16.2% were partially vaccinated. CONCLUSIONS: There is a need for additional theoretical and practical education of our students on blood exposure via accidents, raising the awareness of the necessity of hepatitis B vaccination, and introducing the unique/comprehensive procedure for accident reporting for students and healthcare workers in the entire country.

20.
Int J Clin Pract ; 70(12): 1033-1040, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28032422

ABSTRACT

OBJECTIVE: The aims of our study were to assess the prevalence and distribution of Gram-negative (G-) bacteria in hospital isolates, their sensitivity to the third- and fourth-generation cephalosporins (c3 and c4), therapeutic use of c3 and c4 in the treatment of G- infections and drug utilisation data. RESEARCH DESIGN AND METHODS: This cross-sectional study collected medical records data from the General Hospital "Gornji Milanovac" (GM) and the University Medical Center "Bezanijska kosa" (BK). The time frame of the study was 12 months. Microbiological and clinical parameters, and c3/c4 drug utilisation were analysed. RESULTS: Escherichia coli were the most predominant pathogen in GM and BK, accounting for 43% and 28% of all G- isolates, respectively (GM), 884 G- isolates obtained from 606 patients; BK, 1766 isolates obtained from 1045 patients). Nearly half of the isolates (55% and 43%) were obtained from urine samples collected from the surgical ward (GM), and the internal medicine wards and intensive care unit (BK). On average, the resistance rate of G- strains against c3 and c4 reached 40% and 70%, respectively (lowest in E. coli, 8%-25%; highest in Acinetobacer baumannii, 67%-100%). Resistance rate of Pseudomonas spp. to cefepime and ceftazidime was low/moderate (0%-30% and 19%-47%). In BK, the adult patients were older than in GM (75 vs 66 years), with longer hospital stay (19 vs 10 days) and bacteria were isolated later during hospitalisation (10 vs 2 days). C3 and c4 were more often used in empirical therapy (83% vs 64%) in BK. Ceftazidime and cefepime were used more often in BK than in GM (2.036 vs 69 DDD/y and 586 vs. 126 DDD/y, respectively). CONCLUSION: The use of c3 and c4 in the treatment of G- infections in both hospitals should be re-evaluated in accordance with current guidelines and local resistance.


Subject(s)
Cephalosporins/therapeutic use , Cross Infection/drug therapy , Drug Resistance, Microbial , Gram-Negative Bacterial Infections/drug therapy , Infection Control/methods , Anti-Bacterial Agents/therapeutic use , Cross-Sectional Studies , Gram-Negative Bacteria , Humans , Microbial Sensitivity Tests , Serbia
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