Evaluation of the Cunningham Panel™ in pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection (PANDAS) and pediatric acute-onset neuropsychiatric syndrome (PANS): Changes in antineuronal antibody titers parallel changes in patient symptoms.

OBJECTIVE: This retrospective study examined whether changes in patient pre- and post-treatment symptoms correlated with changes in anti-neuronal autoantibody titers and the neuronal cell stimulation assay in the Cunningham Panel in patients with Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal Infection (PANDAS), and Pediatric Acute-onset Neuropsychiatric Syndrome (PANS). METHODS: In an analysis of all tests consecutively performed in Moleculera Labs' clinical laboratory from April 22, 2013 to December 31, 2016, we identified 206 patients who were prescribed at least one panel prior to and following treatment, and who met the PANDAS/PANS diagnostic criteria. Patient follow-up was performed to collect symptoms and treatment or medical intervention. Of the 206 patients, 58 met the inclusion criteria of providing informed consent/assent and documented pre- and post-treatment symptoms. Clinician and parent-reported symptoms after treatment or medical intervention were categorized as "Improved/Resolved" (n = 34) or "Not-Improved/Worsened" (n = 24). These were analyzed for any association between changes in clinical status and changes in Cunningham panel test results. Clinical assay performance was also evaluated for reproducibility and reliability. RESULTS: Comparison of pre- and post-treatment status revealed that the Cunningham Panel results correlated with changes in patient's neuropsychiatric symptoms. Based upon the change in the number of positive tests, the overall accuracy was 86%, the sensitivity and specificity were 88% and 83% respectively, and the Area Under the Curve (AUC) was 93.4%. When evaluated by changes in autoantibody levels, we observed an overall accuracy of 90%, a sensitivity of 88%, a specificity of 92% and an AUC of 95.7%. Assay reproducibility for the calcium/calmodulin-dependent protein kinase II (CaMKII) revealed a correlation coefficient of 0.90 (p < 1.67 × 10-6) and the ELISA assays demonstrated test-retest reproducibility comparable with other ELISA assays. CONCLUSION: This study revealed a strong positive association between changes in neuropsychiatric symptoms and changes in the level of anti-neuronal antibodies and antibody-mediated CaMKII human neuronal cell activation. These results suggest there may be clinical utility in monitoring autoantibody levels and stimulatory activity against these five neuronal antigen targets as an aid in the diagnosis and treatment of infection-triggered autoimmune neuropsychiatric disorders. Future prospective studies should examine the feasibility of predicting antimicrobial and immunotherapy responses with the Cunningham Panel.

Glucose regulates protein turnover and growth-related mechanisms in rainbow trout myogenic precursor cells.

Rainbow trout are considered glucose intolerant because they are poor utilizers of glucose, despite having functional insulin receptors and glucose transporters. Following high carbohydrate meals, rainbow trout are persistently hyperglycemic, which is likely due to low glucose utilization in peripheral tissues including the muscle. Also, rainbow trout myogenic precursor cells (MPCs) treated in vitro with insulin and IGF1 increase glucose uptake and protein synthesis, whereas protein degradation is decreased. Given our understanding of glucose regulation in trout, we sought to understand how glucose concentrations affect protein synthesis, protein degradation; and expression of genes associated with muscle growth and proteolysis in MPCs. We found that following 24 h and 48 h of treatment with low glucose media (5.6 mM), myoblasts had significant decreases in protein synthesis. Also, low glucose treatments affected the expression of both mstn2a and igfbp5. These findings support that glucose is a direct regulator of protein synthesis and growth-related mechanisms in rainbow trout muscle.

A prospective study of screening for musculoskeletal pathology in the child with a limp or pseudoparalysis using erythrocyte sedimentation rate, C-reactive protein and MRI.

PURPOSE: To determine if the detection of musculoskeletal pathology in children with a limp or acute limb disuse can be optimized by screening with blood tests for raised inflammatory markers, followed by MRI. METHODS: This was a prospective observational study. Entry criteria were children (0 to 16 years of age) presenting to our emergency department with a non-traumatic limp or pseudoparalysis of a limb, and no abnormality on plain radiographs. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) blood tests were performed. Children with ESR > 10 mm/hr or CRP > 10 mg/L underwent a MRI scan. When the location of the pathology causing the limp was clinically unclear, screening images (Cor t1 and Short Tau Inversion Recovery) of both lower limbs from pelvis to ankles ('legogram') was undertaken. Data was gathered prospectively from 100 consecutive children meeting the study criteria. RESULTS: In all, 75% of children had a positive finding on their MRI. A total of 64% of cases had an infective cause for their symptoms (osteomyelitis, septic arthritis, pyomyositis, fasciitis, cellulitis or discitis). A further 11% had positive findings on MRI from non-infective causes (juvenile idiopathic arthritis, cancer or undisplaced fracture). The remaining 25% had either a normal scan or effusion due to transient synovitis. ESR was a more sensitive marker than CRP in infection, since ESR was raised in 97%, but CRP in only 70%. CONCLUSION: In our opinion MRI imaging of all children with a limp and either raised ESR or CRP is a sensitive method to minimize the chance of missing important pathology in this group, and is an effective use of MRI resources. We advocate the use of both blood tests in conjunction. LEVEL OF EVIDENCE: Level II.

Dietary methionine restriction: Effects on glucose tolerance, lipid content and micro-RNA composition in the muscle of rainbow trout.

Lean muscle mass plays an important role in overall health, as altered skeletal muscle metabolism can impact both the incidence and prevention of conditions related to metabolic health. Intriguingly, dietary methionine restriction (MR) has been shown to ameliorate this phenotype over time potentially through mechanisms related to changes in myogenic precursor cell (MPC) differentiation status. Recently the role of micro-RNAs (miRs) in regulating the expression of muscle specific transcription factors myoD and myogenin as well as signaling molecules involved in skeletal muscle differentiation has been reported in vitro. We performed an 8week feeding trial to determine if MR in vivo could alter miR abundance as well as change metabolic markers. Results show changes in muscle miR abundance for miR-133a at 4weeks with no significant difference seen in miR-210 or miR-206. After 8weeks of MR feeding fish demonstrated increased clearance of glucose, increased fat accumulation in the liver, and decreased fat accumulation in the muscle. These data demonstrate conservation of MR effects on fish metabolism, and suggest, for the first time, that miR-133a might play a role in tissue response to MR.

Neurophysiological assessment of acute pain in infants: a scoping review of research methods.

A systematic scoping search to describe the neurophysiological methods used in infant acute pain assessment research was conducted. Of the 2411 abstracts screened, 19 articles were retained. Nine studies utilised near-infrared spectroscopy (NIRS), two utilised functional magnetic resonance imaging (fMRI), and eight utilised electroencephalography (EEG). There was methodological variability in studies utilising NIRS, whereas EEG and fMRI studies reported consistent methods. Of the eight EEG studies, six identified a nociceptive-specific event-related potential. CONCLUSION: While more methodologically rigorous studies are needed, ERPs appear to hold some promise as indicators of infant nociception during clinical procedures to supplement existing measures.

Therapeutic plasma apheresis as a treatment for 35 severely ill children and adolescents with pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections.

BACKGROUND: Because of its reported similarities to Sydenham chorea, therapeutic plasma apheresis (TPA) has been proposed as a potential treatment of pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS). To date, support for the use of TPA has been limited to a few anecdotal reports and a small placebo-controlled trial demonstrating dramatic symptom improvements at 1 month and 1 year follow-up. To evaluate the safety and efficacy of TPA further, we undertook a retrospective review of all PANDAS patients treated with TPA at Georgetown University Hospital between August 2009 and October 2013. METHODS: Forty patients were identified, and sufficient information was available from medical records and telephone interview for 35 cases (88%). All 35 (23 boys; 12 girls) met diagnostic criteria for PANDAS (Swedo et al. 1998 ) and had severe symptoms. The TPA procedures were performed at Georgetown University Hospital using a protocol that processes a total of 4.5 blood volumes over 3-5 days (three treatments of 1.5 volumes each). Overall symptom improvements at 6 months post-TPA and long-term follow-up were estimated by parents, who also rated changes in individual symptoms to provide information about patterns of improvement. RESULTS: All patients were reported to have received at least some benefit from TPA, with average improvement of 65% at 6 months post-TPA and 78% at longer-term follow-up. A decrease in the number of reported symptoms also occurred, with particular improvements in obsessive-compulsive disorder (OCD), anxiety, tics, and somatic symptoms, including dysgraphia, sleep difficulties, and urinary urgency or frequency. Contrary to expectations, preceding duration of illness was not correlated with degree of improvement following TPA, suggesting that acuity of illness is not a factor affecting response. Only two adverse events were reported: both involved reopening of the site where the central line had been placed and resolved immediately following application of pressure and re-dressing of the puncture site. CONCLUSIONS: Therapeutic plasma apheresis is an invasive medical intervention that should be reserved for treatment of children and adolescents who are severely affected by PANDAS. In such patients, it appears to be a safe, well-tolerated, and beneficial treatment option.

Clinical presentation of pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections in research and community settings.

BACKGROUND: The first cases of pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) were described >15 years ago. Since that time, the literature has been divided between studies that successfully demonstrate an etiologic relationship between Group A streptococcal (GAS) infections and childhood-onset obsessive-compulsive disorder (OCD), and those that fail to find an association. One possible explanation for the conflicting reports is that the diagnostic criteria proposed for PANDAS are not specific enough to describe a unique and homogeneous cohort of patients. To evaluate the validity of the PANDAS criteria, we compared clinical characteristics of PANDAS patients identified in two community practices with a sample of children meeting full research criteria for PANDAS. METHODS: A systematic review of clinical records was used to identify the presence or absence of selected symptoms in children evaluated for PANDAS by physicians in Hinsdale, Illinois (n=52) and Bethesda, Maryland (n=40). RESULTS were compared against data from participants in National Institute of Mental Health (NIMH) research investigations of PANDAS (n=48). RESULTS: As described in the original PANDAS cohort, males outnumbered females (95:45) by ∼ 2:1, and symptoms began in early childhood (7.3±2.7 years). Clinical presentations were remarkably similar across sites, with all children reporting acute onset of OCD symptoms and multiple comorbidities, including separation anxiety (86-92%), school issues (75-81%), sleep disruptions (71%), tics (60-65%), urinary symptoms (42-81%), and others. Twenty of the community cases (22%) failed to meet PANDAS criteria because of an absence of documentation of GAS infections. CONCLUSIONS: The diagnostic criteria for PANDAS can be used by clinicians to accurately identify patients with common clinical features and shared etiology of symptoms. Although difficulties in documenting an association between GAS infection and symptom onset/exacerbations may preclude a diagnosis of PANDAS in some children with acute-onset OCD, they do appear to meet criteria for pediatric acute-onset neuropsychiatric syndrome (PANS).

Clinical evaluation of youth with pediatric acute-onset neuropsychiatric syndrome (PANS): recommendations from the 2013 PANS Consensus Conference.

On May 23 and 24, 2013, the First PANS Consensus Conference was convened at Stanford University, calling together a geographically diverse group of clinicians and researchers from complementary fields of pediatrics: General and developmental pediatrics, infectious diseases, immunology, rheumatology, neurology, and child psychiatry. Participants were academicians with clinical and research interests in pediatric autoimmune neuropsychiatric disorder associated with streptococcus (PANDAS) in youth, and the larger category of pediatric acute-onset neuropsychiatric syndrome (PANS). The goals were to clarify the diagnostic boundaries of PANS, to develop systematic strategies for evaluation of suspected PANS cases, and to set forth the most urgently needed studies in this field. Presented here is a consensus statement proposing recommendations for the diagnostic evaluation of youth presenting with PANS.

The misleading appearance of silver nitrate on plain radiography.

Cauterisation with silver nitrate is commonly used to treat overgranulation. Silver nitrate has a high density and a high mass attenuation coefficient, and it is therefore highly radio-opaque. We present a case in which its topical application to an area of overgranulation was interpreted as a bony fragment by the reporting radiologist in a patient with a supracondylar humeral fracture whose radiograph after removal of K-wires showed a large radio-opaque lesion. Although not a new phenomenon, it is one not widely known, and it can lead to confusion and unnecessary further imaging.

Two rare cases of Epstein-Barr virus-associated lymphoproliferative disorders in inflammatory bowel disease patients on thiopurines and other immunosuppressive medications.

The setting of chronic immunosuppression in inflammatory bowel disease (IBD) may promote the proliferation of Epstein-Barr virus-positive neoplastic clones. We report two rare cases of Epstein-Barr virus-associated lymphoproliferative disorder in IBD patients: one resembled lymphomatoid granulomatosis, and the other was a lymphoma resembling Hodgkin lymphoma. There are currently no guidelines for the prevention of lymphoproliferative disorder in IBD patients on immunosuppressive therapy.

Realization of artificial ice systems for magnetic vortices in a superconducting MoGe thin film with patterned nanostructures.

We report an anomalous matching effect in MoGe thin films containing pairs of circular holes arranged in such a way that four of those pairs meet at each vertex point of a square lattice. A remarkably pronounced fractional matching was observed in the magnetic field dependences of both the resistance and the critical current. At the half matching field the critical current can be even higher than that at zero field. This has never been observed before for vortices in superconductors with pinning arrays. Numerical simulations within the nonlinear Ginzburg-Landau theory reveal a square vortex ice configuration in the ground state at the half matching field and demonstrate similar characteristic features in the field dependence of the critical current, confirming the experimental realization of an artificial ice system for vortices for the first time.

Catalyst-free growth of millimeter-long topological insulator Bi2Se3 nanoribbons and the observation of the π-Berry phase.

We report the growth of single-crystalline Bi(2)Se(3) nanoribbons with lengths up to several millimeters via a catalyst-free physical vapor deposition method. Scanning transmission electron microscopy analysis reveals that the nanoribbons grow along the (112̅0) direction. We obtain a detailed characterization of the electronic structure of the Bi(2)Se(3) nanoribbons from measurements of Shubnikov-de Haas (SdH) quantum oscillations. Angular dependent magneto-transport measurements reveal a dominant two-dimensional contribution originating from surface states. The catalyst-free synthesis yields high-purity nanocrystals enabling the observation of a large number of SdH oscillation periods and allowing for an accurate determination of the π-Berry phase, one of the key features of Dirac fermions in topological insulators. The long-length nanoribbons open the possibility for fabricating multiple nanoelectronic devices on a single nanoribbon.

Large magnetoresistance oscillations in mesoscopic superconductors due to current-excited moving vortices.

We show in the case of a superconducting Nb ladder that a mesoscopic superconductor typically exhibits magnetoresistance oscillations whose amplitude and temperature dependence are different from those stemming from the Little-Parks effect. We demonstrate that these large resistance oscillations (as well as the monotonic background on which they are superimposed) are due to current-excited moving vortices, where the applied current in competition with the oscillating Meissner currents imposes or removes the barriers for vortex motion in an increasing magnetic field. Because of the ever present current in transport measurements, this effect should be considered in parallel with the Little-Parks effect in low-critical temperature (T(c)) samples, as well as with recently proposed thermal activation of dissipative vortex-antivortex pairs in high-T(c) samples.

Hydrogen gas sensing with networks of ultrasmall palladium nanowires formed on filtration membranes.

Hydrogen sensors based on single Pd nanowires show promising results in speed, sensitivity, and ultralow power consumption. The utilization of single Pd nanowires, however, face challenges in nanofabrication, manipulation, and achieving ultrasmall transverse dimensions. We report on hydrogen sensors that take advantage of single palladium nanowires in high speed and sensitivity and that can be fabricated conveniently. The sensors are based on networks of ultrasmall (<10 nm) palladium nanowires deposited onto commercially available filtration membranes. We investigated the sensitivities and response times of these sensors as a function of the thickness of the nanowires and also compared them with a continuous reference film. The superior performance of the ultrasmall Pd nanowire network based sensors demonstrates the novelty of our fabrication approach, which can be directly applied to palladium alloy and other hydrogen sensing materials.

Fusion of diphtheria toxin and urotensin II produces a neurotoxin selective for cholinergic neurons in the rat mesopontine tegmentum.

Urotensin II is a neuropeptide first isolated from fish and later found in mammals: where it has potent cardiovascular, endocrine and behavioral effects. In rat brain the urotensin II receptor (UII-R) is predominately expressed in the cholinergic neurons of the pedunculopontine (PPTg) and laterodorsal tegmental nuclei. Typically, the function of the PPTg has been examined using excitotoxins, destroying both cholinergic and non-cholinergic neurons, which confounds interpretation. We took advantage of UII-R's unique expression profile, by combining UII with diphtheria toxin, to engineer a toxin specific for cholinergic neurons of the PPTg. In vitro, two different toxin constructs were shown to selectively activate UII-R (average EC50 approximately 30 nmol/L; calcium mobility assay) and to be 10,000-fold more toxic to UII-R expressing CHO cells, than wildtype cells (average LD50 approximately 2 nmol/L; cell viability). In vivo, pressure injection into the PPTg of rats, resulted in specific loss of choline transporter and NADPH diaphorase positive neurons known to express the UII-R. The lesions developed over time, resulting in the loss of over 80% of cholinergic neurons at 21 days, with little damage to surrounding neurons. This is the first highly selective molecular tool for the depletion of mesopontine cholinergic neurons. The toxin will help to functionally dissect the pedunculopontine and laterodorsal tegmental nuclei, and advance the understanding of the functions of these structures.

Loss of inter-vertebral disc height after anterior cervical discectomy.

Most surgeons undertaking anterior cervical discectomy (ACD) introduce a bone graft or cage into the disc space when the decompression is complete. This is done to prevent segmental collapse, preserve cervical spine alignment and to promote fusion. We have conducted a prospective observational cohort study to investigate the relationship between loss of disc height, cervical spine alignment and clinical outcome in 140 patients undergoing ACD without inter-body graft or cage. At a minimum of 12 months after operation changes in disc space height and cervical spine alignment were correlated with clinical outcome measured by SF36, Neck Disability Index, and visual analogue neck and arm pain scores. There was no relationship between loss of disc height and outcome. Loss of the overall cervical lordosis was present in 71 patients and segmental kyphosis was found in 69. Analysis of clinical outcome showed no significant differences between patients with preserved and abnormal cervical alignment. Neither loss of disc height nor disturbance of cervical alignment compromised clinical outcome in the first year following ACD.

Stopping warfarin therapy is unnecessary for hand surgery.

Interruption of appropriate therapeutic warfarin therapy imposes a risk of morbidity and mortality on the patient. Strategies to reduce the risks of interruption impose relatively large costs in terms of prolonged hospital stay, medication and coagulation monitoring. We report a series of 47 consecutive surgical episodes on the hands of 39 patients without interruption of therapeutic warfarin anticoagulation and with an INR of between 1.3 and 2.9. There was no difficulty with intraoperative haemostasis. Two patients had minor bleeding-related complications with no long-term sequelae. The authors conclude that interruption to warfarin therapy is unnecessary if the INR is less than 3.0 and therefore inappropriate for therapeutically anticoagulated patients undergoing hand surgery.

An examination of d-amphetamine self-administration in pedunculopontine tegmental nucleus-lesioned rats.

The pedunculopontine tegmental nucleus (PPTg) has long been suggested to have a role in reward-related behaviour, and there is particular interest in its possible role in drug reward systems. Previous work found increased i.v. self-administration (IVSA) of d-amphetamine following PPTg lesions when training had included both operant pre-training and priming injections. The present study examined the effect of excitotoxin lesions of the PPTg on d-amphetamine IVSA under three training conditions. Naive: no previous experience of d-amphetamine or operant responding. Pre-trained: given operant training with food before lesion surgery took place. Primed: given single non-contingent d-amphetamine infusion (0.1 mg/0.l ml) at the start of each session. Rats in all conditions were given either ibotenate or phosphate buffer control lesions of the PPTg before d-amphetamine (0.1 mg/0.1 ml infusion) IVSA training took place. Rats received eight sessions of training under a fixed ratio (FR2) schedule of d-amphetamine IVSA, followed by four sessions under a progressive ratio (PR5) schedule. In the naive condition, PPTg-lesioned rats were attenuated in their responding under FR2, and took significantly fewer infusions under PR5 than the control group. Under FR2 in the pre-trained condition, there was no difference between PPTg excitotoxin and control lesioned rats; however, PPTg-lesioned rats took significantly fewer infusions under the PR5 schedule. In the primed condition, there were no differences between PPTg-lesioned and control rats under either FR2 or PR5 schedules. These data demonstrate that operant training prior to PPTg lesion surgery corrects some, but not all, of the deficits seen in the naive condition. PPTg-lesioned rats in both naive and pre-trained conditions showed reduced responding for d-amphetamine under a PR5 schedule. These deficits are overcome by priming with d-amphetamine. We suggest that alterations in striatal dopamine activity following PPTg lesions underlie these effects.

Behavioural sensitisation to repeated d-amphetamine: effects of excitotoxic lesions of the pedunculopontine tegmental nucleus.

The pedunculopontine tegmental nucleus (PPTg) interacts with anatomical systems thought to be involved in mediating sensitisation of the locomotor response to repeated d-amphetamine. The PPTg has direct and indirect connections with the nucleus accumbens and prefrontal cortex, and also influences midbrain dopamine activity through direct projections to substantia nigra and ventral tegmental area. In this experiment, the development of behavioural sensitisation to the locomotor stimulant effects of repeated d-amphetamine was examined in rats bearing excitotoxic lesions of the PPTg, and sham-lesioned controls. Rats were given repeated d-amphetamine (1.5 mg/kg i.p.) treatment in an on-off procedure, with saline and d-amphetamine given on alternate days, such that rats received a total of seven d-amphetamine and seven saline treatments. Locomotor responses were measured in photocell cages. On the first day of d-amphetamine treatment, there was no difference between excitotoxin and sham-lesioned rats. Development of sensitisation to the locomotor stimulant effects of d-amphetamine was delayed in PPTg-lesioned rats, relative to the sham-lesioned control rats. However, there was no difference between lesion and control groups in the locomotion seen on saline-treatment days. These data suggest that the PPTg is involved in the development of behavioural sensitisation to the locomotor stimulant effects of repeated d-amphetamine, and indicate that traditional striatal circuitry models of the mechanisms underlying sensitisation should be extended to include the PPTg.

Refinement of the nickel site structure in Desulfovibrio gigas hydrogenase using range-extended EXAFS spectroscopy.

We have reexamined the Ni EXAFS of oxidized, inactive (as-isolated) and H(2) reduced Desulfovibrio gigas hydrogenase. Better spatial resolution was achieved by analyzing the data over a 50% wider k-range than was previously available. A lower k(min) was obtained using the FEFF code for phase shifts and amplitudes. A higher k(max) was obtained by removing an interfering Cu signal from the raw spectra using multiple energy fluorescence detection. The larger k-range allowed us to better resolve the Ni-S bond lengths and to define more accurately the Ni-O and Ni-Fe bond lengths. We find that as-isolated, hydrogenase has two Ni-S bonds at approximately 2.2 A, but also 1-2 Ni-S bonds in the 2.35+/-0.05 A range. A Ni-O interaction is evident at 1.91 A. The as-isolated Ni-Fe distance cannot be unambiguously determined. Upon H(2) reduction, two short Ni-S bonds persist at approximately 2.2 A, but the remaining Ni-S bonds lengthen to 2.47+/-0.05 A. Good simulations are obtained with a Ni-Fe distance at 2.52 A, in agreement with crystal structures of the reduced enzyme. Although not evident in the crystal structures, an improvement in the fit is obtained by inclusion of one Ni-O interaction at 2.03 A. Implications of these distances for the spin-state of H(2) reduced H(2)ase are discussed.