1. Avraham S, Almog B, Reches A, Zakar L, Malcov M, Sokolov A, Alpern S, Azem F. {{The ovarian response in fragile X patients and premutation carriers undergoing IVF-PGD: reappraisal}}. {Hum Reprod};2017 (May 03):1-4.
STUDY QUESTION: What is the association between the ovarian response and the number of CGG repeats among full mutation and premutation carriers of fragile X (FMR1), undergoing controlled ovarian hyperstimulation (COH) for PGD? SUMMARY ANSWER: Ovarian response was normal in full mutation patients but decreased in premutation carriers, although the number of repeats was not statistically significantly associated with the number of oocytes retrieved. WHAT IS KNOWN ALREADY: There is inconsistent data in the literature regarding ovarian response in FMR1 carriers. Studies exploring the ovarian response of full mutation patients are lacking. STUDY DESIGN, SIZE, DURATION: Retrospective study, a university affiliated tertiary hospital, IVF unit, PGD referral center. PARTICIPANTS/MATERIALS, SETTING, METHODS: We examined the medical records of all women undergoing fresh IVF-PGD cycles due to fragile X. Data recorded included demography, duration of stimulation, amount of gonadotropins administered, number of dominant follicles, maximal E2 levels and number of oocytes retrieved. Data were analyzed using univariate and multivariate mixed models. P-values <0.05 were considered significant. Data were collected from the medical records of 21 patients with a full mutation on the FMR1 gene and 51 premutation carriers. Overall 309 fresh cycles were analyzed. MAIN RESULTS AND THE ROLE OF CHANCE: Premutation carriers displayed reduced ovarian response, as demonstrated by fewer oocytes retrieved. In contrast, full mutation patients had a normal response. Comparison of premutation carriers and full mutation patients showed: mean oocytes retrieved per cycle (8.4 +/- 1.1 versus 14.1 +/- 1.7, P = 0.005), lower levels of estradiol (E2; 1756 +/- 177, versus 2928 +/- 263, P = 0.0004), respectively. There was no significant difference between premutation carriers and full mutation patients in regard to fertilization rate, cleavage rate or biopsy rate. No correlation was found between the number of repeats in the premutation carriers and the number of oocytes retrieved or E2 levels. Age and the type of protocol were the only factors found to be in correlation with the number of the oocyte retrieved (P = 0.037, and P = 0.003, respectively) among the premutation carriers. Similarly, no association was found between the number of repeats and the fertilization rate, cleavage rate or biopsy rate among premutation carriers. LIMITATIONS, REASONS FOR CAUTION: We had a relatively low number of premutation carriers with >100 repeats, which made it challenging to draw a firm conclusions from this group. WIDER IMPLICATIONS OF THE FINDINGS: Physicians must address the increased risk for reduced ovarian response and primary ovarian insufficiency (POI) among carriers and consider surveillance of ovarian reserve markers. The last, might expedite family plans completion or fertility preservation. STUDY FUNDING/COMPETING INTEREST(S): None.
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2. O’Reilly C, Lewis JD, Elsabbagh M. {{Is functional brain connectivity atypical in autism? A systematic review of EEG and MEG studies}}. {PLoS One};2017;12(5):e0175870.
BACKGROUND: Although it is well recognized that autism is associated with altered patterns of over- and under-connectivity, specifics are still a matter of debate. Little has been done so far to synthesize available literature using whole-brain electroencephalography (EEG) and magnetoencephalography (MEG) recordings. OBJECTIVES: 1) To systematically review the literature on EEG/MEG functional and effective connectivity in autism spectrum disorder (ASD), 2) to synthesize and critically appraise findings related with the hypothesis that ASD is characterized by long-range underconnectivity and local overconnectivity, and 3) to provide, based on the literature, an analysis of tentative factors that are likely to mediate association between ASD and atypical connectivity (e.g., development, topography, lateralization). METHODS: Literature reviews were done using PubMed and PsychInfo databases. Abstracts were screened, and only relevant articles were analyzed based on the objectives of this paper. Special attention was paid to the methodological characteristics that could have created variability in outcomes reported between studies. RESULTS: Our synthesis provides relatively strong support for long-range underconnectivity in ASD, whereas the status of local connectivity remains unclear. This observation was also mirrored by a similar relationship with lower frequencies being often associated with underconnectivity and higher frequencies being associated with both under- and over-connectivity. Putting together these observations, we propose that ASD is characterized by a general trend toward an under-expression of lower-band wide-spread integrative processes compensated by more focal, higher-frequency, locally specialized, and segregated processes. Further investigation is, however, needed to corroborate the conclusion and its generalizability across different tasks. Of note, abnormal lateralization in ASD, specifically an elevated left-over-right EEG and MEG functional connectivity ratio, has been also reported consistently across studies. CONCLUSIONS: The large variability in study samples and methodology makes a systematic quantitative analysis (i.e. meta-analysis) of this body of research impossible. Nevertheless, a general trend supporting the hypothesis of long-range functional underconnectivity can be observed. Further research is necessary to more confidently determine the status of the hypothesis of short-range overconnectivity. Frequency-band specific patterns and their relationships with known symptoms of autism also need to be further clarified.
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3. Zahid S, Upthegrove R. {{Suicidality in Autistic Spectrum Disorders}}. {Crisis};2017 (May 03):1-10.
BACKGROUND: It is suggested that people with autistic spectrum disorders (ASD) may be at increased risk of suicide; however, research on this topic has been minimal and there are conflicting reports in existing studies. AIM: To bring together research investigating the prevalence, risk factors, and comorbid factors of suicidality in ASD. METHOD: A systematic search was performed of Medline, Psych Info, Embase, and the Web of Science following PRISMA guidelines. After exclusion criteria were applied, 70 full-text articles were screened. The final review contained 12 papers with a total sample size of 2,651. RESULTS: Prevalence of suicide attempts varied between 7% and 47%, while suicidal ideation was reported in up to 72% of cases. Being male and having a history of self-harm and depression were cited as significant risk factors. LIMITATIONS: Papers were cross sectional and contained a number of limitations. Only one paper used the gold standard for diagnosis of ASD and one a standardized measure of suicidal behavior. CONCLUSION: Suicidal attempts and ideation are increased in ASD; however, the extent of the increase and the risk factors identified within this group remain under-investigated. There is a lack of research on protective factors. The correlation between ASD and suicidality needs further examination with longitudinal research.
