Measurement of Isfahan heavy water zero-power reactor kinetic parameters using advanced pulsed neutron source method in a near critical state

The pulsed neutron source (PNS) technique was used to determine the prompt neutron decay constant for two different lattice pitches in the HWZPR heavy water zero power reactor. The results were compared to the variance-to-mean ratio (VTM) method. The neutron mean generation time was also calculated for both pitches, and the results were compared to previous Monte Carlo calculations. The findings of this research can be used as a benchmark nuclear codes to validate kinetic parameters.

Gene-environment interactions and risk of pediatric-onset multiple sclerosis associated with time spent outdoors

BACKGROUND

Our previous study identified a significant association between lower time spent outdoors, as a proxy of sun exposure, and a higher risk of pediatric-onset multiple sclerosis (POMS). UV radiation modulates the expression of several genes, but it is unknown whether these genes modify the effect of sun exposure on POMS risk.

METHODS

In an age- and sex-matched case-control study, we evaluated the additive and multiplicative interactions between time spent outdoors and genetic non-HLA risk variants for developing POMS within the metabolic pathways of UV radiation, including CD28(rs6435203), CD86(rs9282641), and NFkB1(rs7665090) and the top two HLA risk factors (presence of DRB1×15 and absence of A*02).

RESULTS

In an adjusted model (332 POMS cases, 534 healthy controls), greater time compared to <30 min/day spent outdoors during the prior summer and higher UV radiation dose were associated with decreased odds of POMS (OR 0.66, 95% CI 0.56-0.78, p < 0.001; OR 0.78, 95 % CI 0.62-0.98, p = 0.04, respectively). No significant additive or multiplicative interactions were found between risk factors.

CONCLUSIONS

The exploration of gene-environment interactions in the risk of developing MS can unravel the underlying mechanisms involved. Although we do not have evidence that our candidate genes contribute to interactions, other genes may.

Short-chain fatty acid producers in the gut are associated with pediatric multiple sclerosis onset

OBJECTIVE

The relationship between multiple sclerosis and the gut microbiome has been supported by animal models in which commensal microbes are required for the development of experimental autoimmune encephalomyelitis. However, observational study findings in humans have only occasionally converged when comparing multiple sclerosis cases and controls which may in part reflect confounding by comorbidities and disease duration. The study of microbiome in pediatric-onset multiple sclerosis offers unique opportunities as it is closer to biological disease onset and minimizes confounding by comorbidities and environmental exposures.

METHODS

A multicenter case-control study in which 35 pediatric-onset multiple sclerosis cases were 1:1 matched to healthy controls on age, sex, self-reported race, ethnicity, and recruiting site. Linear mixed effects models, weighted correlation network analyses, and PICRUSt2 were used to identify microbial co-occurrence networks and for predicting functional abundances based on marker gene sequences.

RESULTS

Two microbial co-occurrence networks (one reaching significance after adjustment for multiple comparisons; q < 0.2) were identified, suggesting interdependent bacterial taxa that exhibited association with disease status. Both networks indicated a potentially protective effect of higher relative abundance of bacteria observed in these clusters. Functional predictions from the significant network suggested a contribution of short-chain fatty acid producers through anaerobic fermentation pathways in healthy controls. Consistent family-level findings from an independent Canadian-US study (19 case/control pairs) included Ruminococaccaeae and Lachnospiraceae (p < 0.05). Macronutrient intake was not significantly different between cases and controls, minimizing the potential for dietary confounding.

INTERPRETATION

Our results suggest that short-chain fatty acid producers may be important contributors to multiple sclerosis onset.

Gene-environment interactions increase the risk of paediatric-onset multiple sclerosis associated with household chemical exposures

BACKGROUND

We previously reported an association between household chemical exposures and an increased risk of paediatric-onset multiple sclerosis.

METHODS

Using a case-control paediatric multiple sclerosis study, gene-environment interaction between exposure to household chemicals and genotypes for risk of paediatric-onset multiple sclerosis was estimated.Genetic risk factors of interest included the two major HLA multiple sclerosis risk factors, the presence of DRB1*15 and the absence of A*02, and multiple sclerosis risk variants within the metabolic pathways of common household toxic chemicals, including IL-6 (rs2069852), BCL-2 (rs2187163) and NFKB1 (rs7665090).

RESULTS

490 paediatric-onset multiple sclerosis cases and 716 controls were included in the analyses. Exposures to insect repellent for ticks or mosquitos (OR 1.47, 95% CI 1.06 to 2.04, p=0.019), weed control products (OR 2.15, 95% CI 1.51 to 3.07, p<0.001) and plant/tree insect or disease control products (OR 3.25, 95% CI 1.92 to 5.49, p<0.001) were associated with increased odds of paediatric-onset multiple sclerosis. There was significant additive interaction between exposure to weed control products and NFKB1 SNP GG (attributable proportions (AP) 0.48, 95% CI 0.10 to 0.87), and exposure to plant or disease control products and absence of HLA-A*02 (AP 0.56; 95% CI 0.03 to 1.08). There was a multiplicative interaction between exposure to weed control products and NFKB1 SNP GG genotype (OR 2.30, 95% CI 1.00 to 5.30) but not for other exposures and risk variants. No interactions were found with IL-6 and BCL-2 SNP GG genotypes.

CONCLUSIONS

The presence of gene-environment interactions with household toxins supports their possible causal role in paediatric-onset multiple sclerosis.

High serum neurofilament levels are observed close to disease activity events in pediatric-onset MS and MOG antibody-associated diseases

BACKGROUND

Serum neurofilament light chain (sNfL) is an emerging multiple sclerosis (MS) biomarker which measures neuro-axonal damage. However, understanding its temporal association with disease activity in pediatric-onset MS (POMS) and Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) remains limited.

OBJECTIVE

To investigate the association of sNfL levels and time from disease activity in children with MS and MOGAD.

METHODS

POMS and MOGAD cases with onset before 18 years of age were enrolled at the University of California San Francisco (UCSF) Regional Pediatric MS Center. Frequency-matched healthy subjects were recruited from general pediatric clinics. Serum samples were tested for MOG-IgG at Mayo Clinic using a live cell-based fluorescent activated cell sorting assay. sNfL levels were measured using single-molecule array (Simoa) technology measured in pg/mL. Data on demographics, clinical features, MRI, CSF, and treatment data were collected by chart review.

RESULTS

We included 201 healthy controls healthy controls, 142 POMS, and 20 confirmed MOGAD cases with available sNfL levels. The median (IQR) age at the time of sampling was 15.6 (3.9), 15.5 (3.1), and 8.8 (4.1) years for controls, POMS, and MOGAD, respectively. Median sNfL levels (pg/ml) were higher in POMS (19.6) and MOGAD (32.7) cases compared to healthy controls (3.9) (p<0.001). sNfL levels ≥100 pg/ml were only detected within four months of a clinical event or MRI activity in both POMS and MOGAD cases. In addition, sNfL levels were higher in POMS patients with new/enlarged T2 and gadolinium-enhanced lesions than those without MRI activity within four months of sampling in POMS cases.

CONCLUSION

High sNfL levels were observed close to clinical or MRI events in POMS and MOGAD. Our findings support sNfL as a biomarker of disease activity in pediatric demyelinating disorders.

Neuromotor control associates with muscle weakness observed with McArdle sign of multiple sclerosis

OBJECTIVE

Multiple Sclerosis (MS) is often accompanied by myelopathy, which may be associated with progressive worsening. A specific finding of MS-associated myelopathy is McArdle sign, wherein neck flexion is associated with prominent increased limb weakness relative to that detected with neck extension. In this study, we characterized neuromotor control properties of finger extensors in association with the McArdle sign.

METHODS

A custom-built device was utilized to monitor torque production of the wrist extensors with simultaneous recording of surface electromyography of the extensor digitorum. The electromyography was decomposed and analyzed via both linear and nominal regressions.

RESULTS

Linear regressions demonstrated a strong difference between groups for MS from healthy controls and other myelopathies for motor unit action potential amplitude and average firing rate (p < 0.001). Further, linear regression demonstrated good correlations of neuromotor variables to mechanical torque output (0.24 ≤ R²  ≤ 0.76). Nominal regression distinguished MS from healthy controls with an AUC of 0.87, specificity of 0.97, and sensitivity of 0.64. Nominal regression of MS from other myelopathies demonstrated an AUC of 0.88, specificity of 0.85, and sensitivity of 0.79.

INTERPRETATION

These data demonstrate the neuromotor control factors that largely determine muscle force production change with the observation of McArdle sign; these neuromotor control factors can differentiate MS from both healthy controls and other myelopathy conditions.

McArdle Sign: A Specific Sign of Multiple Sclerosis

OBJECTIVE

To measure McArdle sign (rapidly reversible weakness induced by neck flexion) both qualitatively and quantitatively and to evaluate its specificity and clinical utility for diagnosis of multiple sclerosis (MS).

PATIENTS AND METHODS

In this prospective study, McArdle sign was evaluated by a technician blinded to diagnosis by measuring changes in finger extensor strength in successive trials of neck extension and flexion, first clinically and then with a torque measurement device. We studied 25 healthy controls and 81 patients with finger extensor weakness. Patients were not selected for having McArdle sign. Fifty-two patients had MS, 24 had other myelopathies, and 5 had peripheral nerve lesions accounting for their weakness. The study was conducted between February 1, 2016, and June 30, 2017.

RESULTS

The median clinical McArdle sign and the 2 quantitative measures of neck flexion-induced strength reduction were greater in patients with MS than in the other groups (P<.001). Baseline strength did not confound the difference. The area under the receiver operating characteristic curve was 0.84 (95% CI, 0.75-0.93) comparing patients with MS vs healthy controls and 0.84 (95% CI, 0.75-0.93) comparing MS vs patients with other myelopathies. The 2 quantitative and 1 clinical measurement of McArdle sign by the technician who performed the quantitative testing were correlated (r=.57 and r=.58; P<.001), and in turn, the technician's and unblinded referring physician's clinical assessments were correlated (r=.58; P<.001). McArdle sign was evident in some patients who had minor disability and who were in early phases of MS.

CONCLUSION

McArdle sign, when defined as greater than 10% neck flexion-induced reduction in strength, is entirely specific and 65% sensitive for a diagnosis of MS when compared with other conditions that mimic MS-associated myelopathy. It may facilitate diagnosis in certain clinical situations.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT03122873.

The Management of Insomnia by Tunisian General Practitioners

Introduction

Sleep disorders are common in clinical practice. However, they are relatively poorly understood by doctors. The aim of our study was to describe the management of insomnia by general practitioners (GPs).

Methods

A cross-sectional survey was carried out during the month of Mai 2016. Among the 193 GPs randomly selected from different areas of Sfax, in Tunisia, 127 completed a questionnaire about the management of insomnia.

Results

Among our participants, 46.5% stated that they often discuss the quality of sleep with their patients even when it is not their chief complaint. Forty-three percent reported that they are often consulted by insomniac patients. Twelve percent of GPs declared they know the “sleep diary”. Homeopathic treatment was the most prescribed first line medication (45.3%). Sleep hygiene measures were commonly recommended by 82.7% of the GPs. Relaxation therapy was known by 46.7% of the GPs and used by 26.7%. Sleep-restriction therapy was known and used by respectively 15.8% and 9.2% of participants. Discussing the quality of sleep with patients was correlated to: the frequency of solicitation for insomnia (P = 0.00), the knowledge of sleep diary (P = 0.031), and the recommendation of sleep hygiene measures (P = 0.032).

Conclusion

Continuous medical education, especially concerning non-pharmacological treatment measures, could drastically improve the management of insomnia by Tunisian GPs.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Prevalence of multiple sclerosis in Iranian emigrants: review of the evidence

Iran has the highest prevalence of multiple sclerosis (MS) in the Middle East and Asia. Rate of emigration has been significantly raised among Iranians and though, multiple studies have been published on prevalence of MS among Iranian emigrants. Here we systematically reviewed these publications. We performed a comprehensive literature search was performed on April 30, 2015 in data bases of MEDLINE, EMBASE, Scopus and Google Scholar for the terms 'multiple sclerosis', 'incidence', 'prevalence', 'epidemiology', 'migration', 'emigrant', 'immigrant', 'Iran', 'Parsis' and 'Persian'. Study location, prevalence day or period, and age of at disease onset were recorded for all the included publications. Nine publications from Sweden, Canada, Norway, UK, and India were included. Only three reported age-adjusted prevalence and six reported age of disease onset. MS prevalence among Iranian emigrants varied from 21 per 100,000 people in Bombay, India in 1985 to 433 per 100,000 people in British Columbia, Canada in 2012. Five studies reported the prevalence in the region of interest, ranging from 1.33 in Bombay, India to 240 in British Columbia, Canada. Five studies also reported the prevalence of MS in the population of the destination country, and in all of them, the prevalence of MS was higher in Iranian immigrants compared to native people. Prevalence studies performed in Iran and also on Iranian emigrants indicate roles for both genetic and environmental factors in MS susceptibility. Data might indicate that living in a high-risk area increases the susceptibility to MS.

Multiple sclerosis and hyperprolactinemia: a case-control study

Multiple sclerosis (MS) is an autoimmune disease of central nervous system which is characterized with demyelination. Prolactin, synthesized in the anterior pituitary cells, has a role in maturation of immune cells, suggesting its possible implication in autoreactivity. The aim of the current study is to investigate the role of hyperprolactinemia in MS. Twenty-two MS patients with hyperprolactinemia diagnosed with pituitary adenoma and 66 MS patients without hyperprolactinemia were enrolled in our case-control study. They were matched with regard to age, gender, and MS subtypes. Patients with other concomitant autoimmune diseases and pregnancy were excluded. Statistical analyses were carried out using SPSS (SPSS statistic package, version 21.0.0) statistical software. The Pearson Chi-square test and the t test were used to determine whether there were any significant differences. The level of significance was set at p < 0.05. Greater value of relapse rate among hyperprolactinemic MS patients in comparison to non-hyperprolactinemic MS patients was statistically significant (p < 0.001). Statistically significant difference between the two groups in terms of EDSS was observed (case group vs.

CONTROL

1.3 vs. 1.9; p = 0.007). The correlation between MS duration and duration of hyperprolactinemia was significant in the case group (p < 0.05, R = 0.752). No statistically significant difference was found between two groups regarding duration of MS. This study suggested a protective role of prolactin in demyelinating procedure of MS.

Knowledge and attitude assessment of Iranian multiple sclerosis patients receiving interferon beta

BACKGROUND

Multiple sclerosis (MS) patients permanently confronted with serious challenges from treatment regimen. Developing a new questionnaire in MS management, through evaluation of patients' perspectives and knowledge regarding treatment will help to identify the sources of tension, and to build a therapeutic alliance. We purposed to describe MS patients' understanding of their treatments.

METHODS

About 425 completed and returned questionnaire were assessed of a total of 500 recruited MS patients. The knowledge of correct using interferon-beta (IFN-β) and attitude toward medical care were assessed using self-reported questionnaires consisted of 25 items with validity of multidisciplinary panel and pre-testing on 20 patients.

RESULTS

Knowledge about IFN-β therapy was very low; however, attitude was at a high level. Female patients, self-injection ability, higher educational level, normal functional status, delay from the start of diagnostic workup to definite diagnosis, and being younger were related to a higher level of knowledge. Attitude was associated with functional status, family history of disease and the summary of knowledge variable.

CONCLUSION

Developing educational interventions are needed for MS patients regarding to their low levels of knowledge.

Fatigue, depression, and physical impairment in multiple sclerosis

BACKGROUND

Fatigue, depression, and physical impairment are common among multiple sclerosis (MS) patients. The aim of this study was to determine the relationship between depression, physical impairment, and fatigue in an Iranian MS cohort.

METHODS

Fifty consecutive relapsing-remitting MS patients and 50 age- and sex-matched healthy controls (HCs) were recruited from Sina Rehabilitation Clinic, Tehran, Iran. The depression substance of Hospital Anxiety and Depression Scale (HADS), Expended Disability Status Scale, and Fatigue Severity Scale questionnaires were used to assess depression, physical impairment, and fatigue, respectively.

RESULTS

This study included 38 (76%) females and 12 (24%) males in both patients and HC groups. The depression substance of the HADS in MS and HCs showed a mean value of 1.92 ± 0.80 and 1.17 ± 0.38, respectively (P < 0.001). Pearson's correlation analyses showed that in the MS group depression was associated with fatigue (r = 0.54, P = 0.01), but not with physical impairment (r = 0.16, p = 0.01), while fatigue was associated with both depression (r = 0.54, P = 0.01) and physical impairment (r = 0.36, P = 0.01). Depression in HCs group was also associated with fatigue (r -0.64, P = 0.01).

CONCLUSION

Fatigue is associated with both depression and physical impairment, and an intervention in one of these conditions might improve others.

Parkinsonism associated with multiple sclerosis: A report of eight new cases and a review on the literature

BACKGROUND

Multiple sclerosis (MS) is an autoimmune inflammatory disease that affects the central nervous system. Except tremor, other movement disorders such as Parkinsonism are less frequent in MS. However, some investigations have shown inflammatory and autoimmune aspects of Parkinson's disease. In this study, we report eight new cases of MS who present Parkinson's disease.

METHODS

This retrospective population-based study was carried out on Isfahan MS society between April 2003 and July 2012. A total of 3792 patients with MS were surveyed for Parkinson's disease. Parkinson's disease was approved according to "UK Parkinson disease Brain Bank" criteria. Eligible cases were invited to have an interview with a neurologist. MRI was carried out according to the baseline.

RESULTS

We identified eight patients (three men and five women) who present MS and Parkinson's disease. The mean (±SD) age of onset was 33.3 ± 6.5 (range: 24-42) years for MS and 39.5 ± 8.6 (range: 30-55) years for Parkinson's disease patients. In all patients, MS was preceded Parkinson's disease. Parkinson's disease was developed within mean duration of 6.1 ± 3.4 (range 2-13) years after MS. Focal lesions was shown in six cases, lesions of basal ganglia (BG) in four, lesions of the thalamus in two and lesions of mid-brain in five of cases. In four cases, Parkinsonism occurred before age 40 that is considered as Young-Onset Parkinson's disease.

CONCLUSION

We reported eight patients with MS and Parkinson's disease. To the best of our knowledge, 34 cases of Parkinsonism associating with MS are reported so far. Parkinsonism is a movement disorder, defines as deep gray matter disorder which lead to dopamine deficiency in BG. Investigations have shown that MS could affect deep gray matter structures. Demyelinated lesions in MS and consequence axonal loss in BG and/or nigrostriatal pathway may be responsible for Parkinsonism manifestations in such cases.

Epidemiology of multiple sclerosis in Iran: a systematic review

BACKGROUND

There is a wide variation in the prevalence of multiple sclerosis (MS) in different geographical regions and the epidemiology of MS in Iran has been a major topic of concern during the last decade. Several population-based studies have shown a sharp increase in the prevalence and incidence of MS in this region. In this study, for the first time, the aim was to provide a comprehensive review regarding the incidence and prevalence of MS across Iran.

METHODS

A comprehensive literature search was performed using PubMed, Embase, and Web of Science. We also did a manual search of reference lists from primary articles and relevant reviews. Databases of ongoing research and unpublished literature were also searched.

RESULTS

A total of 22 relevant studies were reviewed and 11 studies met the inclusion criteria. Incidence data were found in 5 studies and ranged from 0.68 to 9.1/100,000 per year in the Iranian population. Prevalence was reported in all studies and ranged from 5.3 to 74.28/100,000 with the higher prevalence among females (female/male ratio ranged from 1.8 to 3.6). The most prevalent subtype of MS was the relapsing-remitting form (65.8-87.8%). The sensory disturbance was the most initial presentation.

CONCLUSION

The incidence and prevalence of MS in Iran has been increasing rapidly, especially in females. Future research should focus on determining the epidemiological features of MS in the neglected provinces with different ethnicities. Such an effort along with further research towards improvement of data on previously studied areas can enable a field to be opened up to identify the patterns of MS in varied genetic backgrounds and environments of Iran.

eIF4F suppression in breast cancer affects maintenance and progression

Levels of eukaryotic initiation factor 4E (eIF4E) are frequently elevated in human cancers and in some instances have been associated with poor prognosis and outcome. Here we utilize transgenic and allograft breast cancer models to demonstrate that increased mammalian target of rapamycin (mTOR) signalling can be a significant contributor to breast cancer progression in vivo. Suppressing mTOR activity, as well as levels and activity of the downstream translation regulators, eIF4E and eIF4A, delayed breast cancer progression, onset of associated pulmonary metastasis in vivo and breast cancer cell invasion and migration in vitro. Translation of vascular endothelial growth factor (VEGF), matrix metallopeptidase 9 (MMP9) and cyclin D1 mRNAs, which encode products associated with the metastatic phenotype, is inhibited upon eIF4E suppression. Our results indicate that the mTOR/eIF4F axis is an important contributor to tumor maintenance and progression programs in breast cancer. Targeting this pathway may be of therapeutic benefit.

[Isolated radiocarpal luxation. A case report and general review of the literature]

PURPOSE OF THE STUDY

We describe a case of an isolated radiocarpal dislocation and review the literature.

CASE REPORT

A young 29-year-old male, suffering from a wrist injury after a motor cycle accident, was diagnosed as dorsal radiocarpal joint dislocation with distal radioulnar dislocation and no fracture, close reduction was immediately performed followed by plaster cast immobilisation. After five months satisfactory stability and motion were obtained without signs of carpal instability.

DISCUSSION

This pathology is exceptional with less than 15 published cases. Dislocation is due to wrist hyperextension with ulnar motion but without, probably, intracarpal supination. After immediate treatment, this lesion appeared to have a good prognosis without post-traumatic carpal instability, when compared to the poorer result of perilunar dislocation.