Cutaneous allodynia in pediatric and adolescent patients and their mothers: A comparative study.

BACKGROUND: Allodynia in adults with migraine is related to disease duration. In pediatric patients with migraine, the same proportion reported allodynia in the first six months of migraine presentation as in prolonged disease. This study examined a possible association between migraine pediatric allodynia and maternal allodynia. METHODS: We interviewed children with migraine first, and then their mothers, regarding allodynia and headache symptoms. We reviewed hospital charts on pediatric medical background and headache symptoms. Mothers and children older than 11 years filled the Strengths and Difficulties Questionnaire. RESULTS: Ninety-eight children with migraine, mean age 13.49 ± 3.1 years, and their mothers, mean age 43.5 ± 6.2 years were recruited to the study. Pediatric allodynia was associated with maternal allodynia; the latter was reported in 82.8% of children with allodynia versus 35.3% of children without allodynia (p < 0.001). Maternal migraine was reported in 44 (68.7%) of children with allodynia versus 16.3% without allodynia, p < 0.001. No difference was found in Strengths and Difficulties Questionnaire scores, between children with and without allodynia. CONCLUSIONS: Pediatric allodynia is associated with maternal migraine. Genetic and environmental factors such as maternal behavior may contribute to reduced pain threshold.

Thunderclap Headache in Children and Adolescents.

PURPOSE OF REVIEW: This work aimed to review the epidemiology, clinical criteria, and primary and secondary diagnoses of pediatric thunderclap headache and to compare to adult thunderclap headache. RECENT FINDINGS: Thunderclap headache among children aged 6-18 years are rare; this headache presented in 0.08% of the patients admitted to a pediatric emergency department in a tertiary pediatric center. In that recent single-center study, thunderclap was a headache of grade 10 on the pain scale and conferred a benign course. Contrary to adults, in children, most thunderclap headaches are due to either a primary thunderclap headache or another type of primary headache. A number of case reports have attributed pediatric thunderclap to reversible vasoconstriction syndrome and bleeding due to intracranial aneurysm. However, 3-year data from a pediatric emergency department of one center did not find these reasons to be causes of secondary thunderclap headache. This may be due to the rarity of these diagnoses in children compared to adults. Four of the 19 patients with thunderclap headache reported in that single study had secondary thunderclap; the causes were infection in three and malignant hypertension in one. All the patients had a benign course. Although urgent imaging and lumbar puncture are required in the workup of pediatric thunderclap, severe causes are very rare. More research is needed to investigate pediatric thunderclap headache.

Severe abrupt (thunderclap) non-traumatic headache at the pediatric emergency department - a retrospective study.

BACKGROUND: Adult abrupt severe non-traumatic headache (thunderclap) is often related to serious underlying etiologies such as subarachnoid hemorrhage. However, data are sparse regarding thunderclap headache in the pediatric population. OBJECTIVE: The aim of the study was to evaluate the prevalence, characteristics and causes of thunderclap headache in the pediatric and adolescent population, aged 6-18 years, presenting to a pediatric emergency department. METHODS: The electronic database of a tertiary care pediatric emergency department was searched for children presenting with acute headache during 2016-2018. Headache severity was defined by pain scales, either a visual analogue scale or by the Faces Pain Scale-Revised. RESULTS: Thunderclap headache was diagnosed in 19/2290 (0.8%) of the included patients, all of them with a pain score of 10/10. All the patients had a benign course. Primary headache was diagnosed in 15/19 (78.9%), six patients had migraine and eight were diagnosed with primary thunderclap headache. Four of the 19 patients were diagnosed with secondary headache: three with infectious causes and one with malignant hypertension. CONCLUSIONS: Thunderclap headache is rare among children and adolescents presenting to the emergency department. This headache is generally of a primary origin. Extensive evaluation is still needed to rule out severe diagnosis problems.

Trigeminal neuralgia in children and adolescents: Experience of a tertiary pediatric headache clinic.

OBJECTIVES: To describe the characteristics and treatment of trigeminal neuralgia in children attending a dedicated pediatric headache clinic. BACKGROUND: Data on trigeminal neuralgia as a cause of headache are largely derived from adult studies. Little is known about the etiology, symptoms, treatment, and outcome of the disorder in children and adolescents. METHODS: A case series study was undertaken. The database of a headache clinic within a tertiary, university-affiliated, pediatric medical center was searched for all patients aged 3-18 years presenting with clinical and epidemiological features of trigeminal neuralgia or trigeminal neuropathy from January 2015 to December 2019. The diagnosis was revised for the present study according to the criteria of the International Classification of Headache Disorders, third edition. Data on demographic parameters, clinical symptoms, treatment, and outcome were collected from the medical files. RESULTS: Of the 1040 patients who presented to our clinic during the study period, five (0.5%) were diagnosed with trigeminal neuralgia. Mean patient age was 15.1 ± 3.0 years (range 9.5-17.5; 95% CI 10.8-18.9). All had idiopathic type: purely paroxysmal in one and with concomitant continuous pain in four. Findings on herpes serology in all five and magnetic resonance imaging were normal in four patients. In the fifth, a vascular ring was noted from the superior cerebellar artery around the right trigeminal nerve without radiologic evidence of vascular nerve compression. All patients were initially treated with carbamazepine: one reported partial relief, two did not respond, and two had severe adverse effects. Three patients were switched to gabapentin but only one responded well. Three patients were treated with nerve block. CONCLUSION: Trigeminal neuralgia accounted for only a small proportion of patients seeking treatment for headache in pediatric headache clinic over a 5-year period. Unlike findings in adults, vascular compression was not the underlying mechanism in any of our patients. The response to pharmacologic treatment was poor. Nerve block may serve as an alternative when pharmacologic treatment fails.

Cephalic cutaneous allodynia in children and adolescents with migraine of short duration: A retrospective cohort study.

BACKGROUND: Allodynia is prevalent in adults with migraine and has been associated with long disease duration and severe course. Studies of the pediatric population are sparse. The aim of this study was to evaluate the rate of cephalic cutaneous allodynia in children and adolescents within the first 6 months of migraine onset and to identify associated clinical and migraine-related parameters. METHODS: The electronic database of a tertiary pediatric headache clinic from 2014 to 2017 was retrospectively searched for all children and adolescents diagnosed with migraine headache within 6 months or less of symptom onset. Cephalic cutaneous allodynia was identified by validated questionnaire. Demographics, symptoms, and headache-related parameters were compared between patients with and without allodynia. RESULTS: The cohort included 119 patients, 69 girls (58.0%) and 50 (42.0%) boys, of mean age 11.6 ± 3.6 years. Mean time since onset of migraine disease was 3.6 ± 1.8 months. Cephalic cutaneous allodynia was reported by 31.1% of patients. It was significantly associated with female gender ( p = 0.03), older age at admission ( p = 0.037), older age at onset ( p = 0.042) migraine with aura ( p = 0.002), and higher rate of awakening pain ( p = 0.017). CONCLUSIONS: Cephalic cutaneous allodynia may occur in children and adolescents already in the first 6 months of migraine onset. Contrary to adult studies, we found no association of allodynia with migraine frequency or long disease duration. Allodynia was significantly associated with migraine with aura, female gender, and awakening pain. A genetic tendency may contribute to the appearance of allodynia in the pediatric age group.

Headache in pediatric and adolescent patients with chronic kidney disease, with and without hemodialysis: A comparative cohort study.

Background Several studies have reported dialysis-related headache in adults. We investigated headache and its characteristics in pediatric and adolescent patients with chronic kidney disease and patients treated with dialysis, and compared characteristics of patients with and without headache in the entire cohort and separately among dialysis and among chronic kidney disease patients. Methods Patients and their parents who attended a nephrology clinic and hemodialysis unit were interviewed regarding the existence of headache and its characteristics. We reviewed hospital files for medical history, blood test results, and pharmacologic treatment. Headache was defined according to International Headache Society criteria. Results The cohort comprised 60 patients: 39 with chronic kidney disease without hemodialysis and 21 treated with hemodialysis; 39 were males, mean age 11.9 ± 5.3 years. Twenty-six (43.3%) reported experiencing headaches. The hemodialysis group had a higher rate of headache than the chronic kidney disease patients, at 76.2% vs. 25.5%, p < 0.001. In the hemodialysis group, 15 out of 16 reported dialysis-related headache; 14 (87.5%) of these had migraine characteristics. For the entire cohort, headache was associated with hemodialysis, chronic kidney disease grade, lower glomerular filtration rate anemia and a higher parathyroid hormone level. In logistic regression analysis, glomerular filtration rate was significantly associated with headache, odds ratio 2.74 (95% CI 1.56-4.82, p < 0.001). Conclusions A high rate of headache, mostly migraine type, was reported by hemodialysis patients. Hemodialysis, anemia, higher parathyroid hormone levels, phosphate, and lower glomerular filtration rate are strongly associated with headache among chronic kidney disease pediatric and adolescent patients.

Bacteriorhodopsin based non-magnetic spin filters for biomolecular spintronics.

We discuss spin injection and spin valves, which are based on organic and biomolecules, that offer the possibility to overcome some of the limitations of solid-state devices, which are based on ferromagnetic metal electrodes. In particular, we discuss spin filtering through bacteriorhodopsin in a solid state biomolecular spin valve that is based on the chirality induced spin selectivity (CISS) effect and shows a magnetoresistance of ∼2% at room temperature. The device is fabricated using a layer of bacteriorhodopsin (treated with n-octyl-thioglucoside detergent: OTG-bR) that is adsorbed on a cysteamine functionalized gold electrode and capped with a magnesium oxide layer as a tunneling barrier, upon which a Ni top electrode film is placed and used as a spin analyzer. The bR based spin valves show an antisymmetric magnetoresistance response when a magnetic field is applied along the direction of the current flow, whereas they display a positive symmetric magnetoresistance curve when a magnetic field is applied perpendicular to the current direction.

Mycobacterium marinum: a rare cause of chronic lymphocutaneous syndrome.

We investigated the prevalence of Mycobacterium marinum lymphadenitis and describe 4 children with the disease. The database of the microbiology laboratory of a tertiary pediatric medical center was searched for all cases of nontuberculous mycobacterial lymphadenitis from 1996 to 2016. M. marinum lymphadenitis was defined as isolation of the pathogen from a lymph node or from a skin lesion with an enlarged regional lymph node. M. marinum was isolated from lymph nodes in 2 of 167 patients with nontuberculous mycobacterial lymphadenitis and from skin lesions in 2 children with skin lesions and regional reactive lymphadenitis, yielding a 2.4% prevalence of M. marinum lymphadenitis. All 4 affected children were younger than 7 years and had been referred for evaluation of enlarged lymph nodes. Preauricular/submandibular and inguinal lymph nodes (n = 2 each) were involved. Three patients had skin traumas and visited the same natural spring. The diagnosis was delayed because a history of aquatic exposure was initially missed. Two children were managed with anti-mycobacterial antibiotics and 2 by observation only. All showed good resolution. CONCLUSION: A detailed history, specifically regarding exposure to spring water sources, in cases of lymphocutaneous syndrome can point to the diagnosis of M. marinum infection. What is Known: • M. marinum can cause chronic nodular or ulcerative skin infections. • Lymphadenitis due to M. marinum has rarely been reported. What is New: • M. marinum infection can present as isolated chronic lymphadenitis; it accounts for about 2.4% of all cases of nontuberculous mycobacterial lymphadenitis and it tends to occur in noncervicofacial regions relative to infections of other nontuberculous mycobacterial species. • Careful history taking including water source exposure, especially in association with skin trauma, can point to the correct diagnosis in children with chronic lymphadenitis.

Obesity and Migraine in Childhood.

PURPOSE OF REVIEW: The purpose of this work was to review the current literature on the epidemiology and pathophysiology of pediatric obesity and migraine, underlying pathogenic mechanisms that may explain the association between the two disorders, and the effects of treatment. RECENT FINDINGS: In children and adolescents, the bulk of the available data support an association between obesity and headache disorders in general, though a small number of studies contradict these findings. Relative to the adult population, however, few studies have focused specifically on migraine, and no wide-ranging meta-analyses have been conducted to date. It seems that the pathophysiology of obesity and migraine in adults holds true for the pediatric population as well. The association between obesity and migraine in the pediatric population is likely to be multifactorial and to involve both central and peripheral mechanisms. More attention is currently being addressed to the role of the hypothalamus and the bioactive neurotransmitters and neuropeptides that modulate energy homeostasis, namely serotonin, orexin, and the adiponectins, in migraine. A few innovative studies have demonstrated some benefit for migraine from weight reduction treatments such as exercise and lifestyle management. Many open questions remain regarding the modifiable nature of the obesity-migraine relationship and its implications in clinical practice. Further studies of these issues are needed.

Comparison of comorbidities of migraine and tension headache in a pediatric headache clinic.

Objective To compare comorbidities between migraine and tension headache in patients treated in a tertiary pediatric headache clinic. Methods Files of patients with migraine or tension headache attending a pediatric headache clinic were retrospectively reviewed for the presence of organic comorbidities. Additionally, patients were screened with the self-report Strengths and Difficulties Questionnaire to identify nonorganic comorbidities. If necessary, patients were referred to a pediatric psychiatrist, psychologist or social worker for further evaluation. Results The study cohort comprised 401 patients: 200 with migraine and 201 with tension headache. The main organic comorbidities were atopic disease, asthma, and first-reported iron-deficiency anemia; all occurred with statistical significance more often with migraine than with tension headache (Familial Mediterranean fever was six times more frequent in the migraine group than in the tension headache group, but the difference was not statistically significant. Nonorganic comorbidities (psychiatric, social stressors) were associated significantly more often with tension headache than with migraine (48.3% versus 33%; p = 0.03). Conclusions Children and adolescents with migraine or tension headache treated in a dedicated clinic have high rates of organic and nonorganic comorbidities. In this setting, patients with migraine have significantly more organic comorbidities, and patients with tension headache, significantly more nonorganic comorbidities.

Vomiting and migraine-related clinical parameters in pediatric migraine.

OBJECTIVE/BACKGROUND: To investigate the characteristics of vomiting in pediatric migraineurs and the relationship of vomiting with other migraine-related parameters. METHODS: The cohort included children and adolescents with migraine attending a headache clinic of a tertiary pediatric medical center from 2010 to 2016. Patients were identified by a retrospective database search. Data were collected from medical files. The presence of vomiting was associated with background and headache-related parameters. RESULTS: The study group included 453 patients, 210 boys (46.4%) and 243 girls (53.6%), of mean age 11.3 ± 3.7 years. Vomiting was reported by 161 patients (35.5%). On comparison of patients with and without vomiting, vomiting was found to be significantly associated with male gender (54% vs 42.1%, P < .018), younger age at migraine onset (8.0 ± 3. years vs 9.6 ± 3.7 years, P < .001), younger age at clinic admission (10.5 ± 3. years vs 11.6 ± 3.6 years, P = .002), higher rate of awakening headache (64.1% vs 38.7%, P < .001), lower headache frequency (10.5 ± 10.3 headaches/month vs 15.0 ± 11.7 headaches/month, P < .001), higher rate of episodic vs chronic migraine (67% vs 58.7%, P < .001), and higher rates of paternal migraine (24.1% vs 10.1%, P < .001), migraine in both parents (9.3% vs 3.1%, P = .007), and migraine in either parent (57.5% vs 45.5%, P = .02). CONCLUSIONS: The higher rate of vomiting in the younger patients and the patients with awakening pain may be explained by a common underlying pathogenetic mechanism of vomiting and migraine involving autonomic nerve dysfunction/immaturity. The association of vomiting with parental migraine points to a genetic component of vomiting and migraine. It should be noted that some of the findings may simply reflect referral patterns in the tertiary clinic.

Symptoms and clinical parameters of pediatric and adolescent migraine, by gender - a retrospective cohort study.

BACKGROUND: The available data on gender differences in clinical migraine parameters among pediatric patients are based on relatively few studies, which did not use the current version of the International Classification of Headache Disorders (ICHD) of the International Headache Society. The aim of the present study was to compare between males and females, demographic and clinical characteristics of children and adolescents with migraines diagnosed according to the ICDIII-beta version. METHODS: The electronic database of a tertiary pediatric headache clinic was searched for all children and adolescents diagnosed with migraine headaches in 2010-2016. Data on demographics, symptoms, and headache-related parameters were collected from the medical files. Findings were compared by gender. RESULTS: The cohort included 468 children and adolescents of mean age 11.3 ± 3.6 years; 215 males (45.9%) and 253 females (54.1%). Migraine without aura was documented in 313 patients (66.9%), and migraine with aura in 127 (27.1%); 28 patients (6.0%) had probable migraines. The female patients had significantly higher values than the male patients for the following parameters: age at admission (p = 0.042, Cohen's d 0.8303, 95% CI 0.614-0.992); age at migraine onset (p = 0.021, Cohen's d 0.211, 95% CI 0.029-0.394); rate of migraine with aura (OR 2.01, 95% CI 1.29-3.16, p = 0.0056); headache frequency (p = 0.0149, Cohen's d 0.211, 95% CI 0.029-0.3940); rate of chronic migraine (p = 0.036, OR 1.54, 95% CI 1.02-2.34); and puberty (OR 3.51, 95% CI 2.01-6.35, p = <0.001). Males had a higher rate of vomiting (OR 0.62, 95% CI 0.41-0.93, p = 0.018). Further analysis by pubertal stage revealed that pubertal females, but not prepubertal females, had a significantly higher rate of migraine with aura than did males (41.1% versus 28.9%; OR 1.42, 95% CI 0.85-2.37, p = 0.039). CONCLUSION: Female children and adolescents with migraine treated in a tertiary pediatric headache clinic were characterized by a higher rate of chronic migraine and migraine with aura, a lower rate of vomiting, and older age at onset relative to males. These findings might be influenced by the better description of migraine symptoms by females owing to their better verbal ability.

Factors Influencing Response to Pharmacologic Treatment of Migraine in a Pediatric Headache Clinic.

OBJECTIVE: The responses of different patients to the same drug may vary as a consequence of biologic, psychosocial, and genetic differences. The aim of this study was to identify clinical factors associated with a response to pharmacologic treatment in pediatric patients with migraine. METHODS: The medical files of patients with migraine attending the headache clinic of a tertiary pediatric medical center in 2010-2015 were reviewed. The children and parents (or only the parents if the child was very young) completed the International Headache Society-based questionnaire. Patients were treated with at least one of the following medications: propranolol, amitriptyline, topiramate. Response to treatment was rated as no change in migraine pattern (grade 1) or a decrease in migraine attack frequency per month by at least 50% (grade 2) or at least 75% (grade 3). The highest-grade response to any pharmacologic treatment was defined as the best clinical response. RESULTS: The study group included 248 patients of mean age 12.71 ± 3.04 years. A grade 3 best clinical response was significantly associated with a positive maternal history of migraine, younger age at treatment onset, lower frequency of headache attacks per month, postpubertal children had a significantly lower rate of grade 3 response than prepubertal children (P < .05). Analysis of the association of overuse of medication and treatment response achieved a P value equal to .05. CONCLUSIONS: Several background and clinical factors are identified that may predispose children with migraine to respond better to pharmacologic treatment. Clinicians who see children with migraine in a pediatric headache clinic setting should consider these factors before initiating a treatment program.

Spin-dependent electron transmission through bacteriorhodopsin embedded in purple membrane.

Spin-dependent photoelectron transmission and spin-dependent electrochemical studies were conducted on purple membrane containing bacteriorhodopsin (bR) deposited on gold, aluminum/aluminum-oxide, and nickel substrates. The result indicates spin selectivity in electron transmission through the membrane. Although the chiral bR occupies only about 10% of the volume of the membrane, the spin polarization found is on the order of 15%. The electrochemical studies indicate a strong dependence of the conduction on the protein's structure. Denaturation of the protein causes a sharp drop in the conduction through the membrane.

Association of age at onset of migraine with family history of migraine in children attending a pediatric headache clinic: a retrospective cohort study.

AIM: Migraine is known to run in families and has long been considered a strongly heritable disorder. This study sought to evaluate the relationship between age at onset of pediatric migraine and family history of migraine. METHODS: Review of the medical files of the headache clinic of a tertiary pediatric medical center yielded 344 children with migraine for whom details on migraine in family members were available. RESULTS: Mean age of the cohort was 11.69 ± 3.49 years, and mean frequency of headache per month, 13.68 ± 11.26. Mean age at migraine onset in patients with a negative parental history was10.48 ± 3.39 years; in patients with one parent with migraine, 8.84 ± 3.72 years; and in patients with both parents with migraine, 7.32 ± 3.22 years (p < 0.001).The duration of migraine attacks (in hours) was significantly longer in patients with any family member with migraine than in those with no family history (p = 0.026). CONCLUSIONS: Among children attending a tertiary pediatric headache clinic, migraine appears at a younger age in those with parental history of migraine than in those with a negative family history. The findings suggest that having a genetic background of migraine makes a child more susceptible to migraine earlier in life than a child without a family history.

Photoswitching kinetics and phase-sensitive detection add discriminative dimensions for selective fluorescence imaging.

Non-invasive separation-free protocols are attractive for analyzing complex mixtures. To increase selectivity, an analysis under kinetic control, through exploitation of the photochemical reactivity of labeling contrast agents, is described. The simple protocol is applied in optical fluorescence microscopy, where autofluorescence, light scattering, as well as spectral crowding presents limitations. Introduced herein is OPIOM (out-of-phase imaging after optical modulation), which exploits the rich kinetic signature of a photoswitching fluorescent probe to increase selectively and quantitatively its contrast. Filtering the specific contribution of the probe only requires phase-sensitive detection upon matching the photoswitching dynamics of the probe and the intensity and frequency of a modulated monochromatic light excitation. After in vitro validation, we applied OPIOM for selective imaging in mammalian cells and zebrafish, thus opening attractive perspectives for multiplexed observations in biological samples.

Identification of a novel mutation in the PNLIP gene in two brothers with congenital pancreatic lipase deficiency.

Congenital pancreatic lipase (PNLIP) deficiency is a rare monoenzymatic form of exocrine pancreatic failure characterized by decreased absorption of dietary fat and greasy voluminous stools, but apparent normal development and an overall good state of health. While considered to be an autosomal recessive state affecting a few dozens of individuals world-wide and involving the PNLIP gene, no causative mutations for this phenotype were so far reported. Here, we report the identification of the homozygote missense mutation, Thr221Met [c.662C>T], in two brothers from a consanguineous family of Arab ancestry. The observed genotypes among the family members were concordant with an autosomal recessive mode of inheritance but moreover a clear segregation between the genotype state and the serum PNLIP activity was evident. Based on biophysical computational tools, we suggest the mutation disrupts the protein's stability and impairs its normal function. Although the role of PNLIP is well established, our observations provide genetic evidence that PNLIP mutations are causative for this phenotype.

Characteristics and management of arachnoid cyst in the pediatric headache clinic setting.

OBJECTIVE/BACKGROUND: Arachnoid cysts are generally identified incidentally on brain imaging, although they occasionally cause symptoms because of expansion or bleeding. This study aims to describe patients in whom an arachnoid cyst was identified on magnetic resonance imaging (MRI) study performed for the evaluation of headache in a pediatric headache clinic and to highlight the clinical dilemma posed by this finding. METHODS: A retrospective descriptive study design was used. The electronic database of a tertiary pediatric headache clinic was searched for all newly admitted patients with headache who underwent MRI evaluation in 2008-2013. The indications for imaging were based on clinical practice parameters recommended by the Subcommittee of the American Academy of Neurology. Clinical and imaging parameters were collected from the files. Findings were compared between patients with and without an arachnoid cyst. RESULTS: Of the 250 (31%) of 800 patients who met the inclusion criteria, 11 (4.4%) had an arachnoid cyst. Two patients had a ruptured cyst with midline shifting and a large subdural collection. Both presented with headache, vomiting, phonophobia, and photophobia. In the other 9 asymptomtic patients with an arachnoid cyst, imaging showed only a mild mass effect without midline shifting; their symptoms were considered unrelated to the cyst. The patients with a symptomatic arachnoid cyst were referred for surgery, with good outcome. CONCLUSIONS: Arachnoid cysts are found in a small percentage of brain scans performed for evaluation of headache in the setting of a hospital-based pediatric headache clinic. For the long run in these clinical settings, most of the cysts are asymptomatic. Precise anamnesis, neurologic examination, and imaging performed according to accepted practice guidelines may help clinicians determine if the headache and symptoms are caused by the cyst or if they should seek primary headache diagnosis with overlapping symptoms. The clinical distinction between symptomatic and asymptomatic patients (symptoms that are directly related to the arachnoid cyst) may be difficult. Family history of migraine may help in the diagnosis of asymptomatic patients.

MRI white matter lesions in pediatric migraine.

OBJECTIVES: Studies have reported an association between migraine and white matter hyperintensities on T2-weighted brain magnetic resonance imaging (MRI) in adults. The aim of the present study was to evaluate white matter MRI brain findings in pediatric patients with migraine. METHODS: The medical files and imaging scans of all 194 patients who underwent brain MRI at the headache clinic of a tertiary medical center in 2008-2011 were reviewed. RESULTS: Mean age was 10.9 ± 3.5 years. Migraine was diagnosed in 131 patients and other disorders in 63. In the migraine group, findings on physical and laboratory examinations were within normal range. White matter lesions were identified on MRI scan in 14 children with migraine (10.6%) and none of the children with other disorders ( P = 0.006). In 13/14 patients, the lesions were focal with a variable distribution; in the remaining patient, confluent periventricular hyperintensities were documented. CONCLUSIONS: In a headache clinic of a tertiary pediatric medical center, white matter lesions are found in about 10% of pediatric patients with migraine.

Spin specific electron conduction through DNA oligomers.

Spin-based properties, applications, and devices are commonly related to magnetic effects and to magnetic materials. Most of the development in spintronics is currently based on inorganic materials. Despite the fact that the magnetoresistance effect has been observed in organic materials, until now spin selectivity of organic based spintronics devices originated from an inorganic ferromagnetic electrode and was not determined by the organic molecules themselves. Here we show that conduction through double-stranded DNA oligomers is spin selective, demonstrating a true organic spin filter. The selectivity exceeds that of any known system at room temperature. The spin dependent resistivity indicates that the effect cannot result solely from the atomic spin-orbit coupling and must relate to a special property resulting from the chirality symmetry. The results may reflect on the importance of spin in determining electron transfer rates through biological systems.