Ion Exchange Kinetics. A Nonlinear Diffusion Problem

Ideal limiting laws are calculated for the kinetics of particle diffusion controlled ion exchange processes involving ions of different mobilities between spherical ion exchanger beads of uniform size and a well-stirred solution. The calculations are based on the nonlinear Nernst-Planck equations of ionic motion, which take into account the effect of the electric forces (diffusion potential) within the system. Numerical results for counter ions of equal valence and six different mobility ratios are presented. They were obtained by use of a digital computer. This approach contains the well-known solution to the corresponding linear problem as a limiting case. An explicit empirical formula approximating the numerical results is given

Acute flaccid myelitis and Guillain-Barre syndrome in children:A comparative study with evaluation of diagnostic criteria

BACKGROUND AND PURPOSE: Differentiation between acute flaccid myelitis (AFM) and Guillain–Barré syndrome (GBS) can be difficult, particularly in children. Our objective was to improve the diagnostic accuracy by giving recommendations based on a comparison of clinical features and diagnostic criteria in children with AFM or GBS. METHODS: A cohort of 26 children with AFM associated with enterovirus D68 was compared to a cohort of 156 children with GBS. The specificity of the Brighton criteria, used for GBS diagnosis, was evaluated in the AFM cohort and the specificity of the Centers for Disease Control and Prevention (CDC) AFM diagnostic criteria in the GBS cohort. RESULTS: Children with AFM compared to those with GBS had a shorter interval between onset of weakness and nadir (3 vs. 8 days, p < 0.001), more often had asymmetric limb weakness (58% vs. 0%, p < 0.001), and less frequently had sensory deficits (0% vs. 40%, p < 0.001). In AFM, cerebrospinal fluid leukocyte counts were higher, whereas protein concentrations were lower. Spinal cord lesions on magnetic resonance imaging were only found in AFM patients. No GBS case fulfilled CDC criteria for definite AFM. Of the AFM cases, 8% fulfilled the Brighton criteria for GBS, when omitting the criterion of excluding an alternate diagnosis. CONCLUSIONS: Despite the overlap in clinical presentation, we found distinctive early clinical and diagnostic characteristics for differentiating AFM from GBS in children. Diagnostic criteria for AFM and GBS usually perform well, but some AFM cases may fulfill clinical diagnostic criteria for GBS. This underlines the need to perform diagnostic tests early to exclude AFM in children suspected of atypical GBS

Prognostic factors for relapse and outcome in pediatric acute transverse myelitis

Objective: It may be difficult for clinicians to estimate the prognosis of pediatric acute transverse myelitis (ATM). The aim of this study was to define prognostic factors for relapsing disease and poor outcome in pediatric ATM.Methods: This prospective cohort study included 49 children, 18 boys and 31 girls (median age 13.1 years, IQR 6.5-16.2) with a first episode of ATM. Factors associated with relapsing disease and poor outcome (Expanded Disability Status Scale (EDSS) &gt;= 4) were assessed during a median follow-up of 37 months (IQR 18-75).Results: In total, 14 patients (29%) experienced &gt;= 1 relapse(s) and nine patients (18%) had a poor outcome. Factors at onset associated with relapsing disease included higher age (16.1 vs. 11.6 years, p = 0.002), longer time to maximum severity of symptoms (5.5 vs. 3 days, p = 0.01), lower maximum EDSS score (4.0 vs. 6.5, p = 0.003), short lesion on spinal MRI (64 vs. 21%, p = 0.006), abnormalities on brain MRI (93 vs. 44%, p = 0.002) and presence of oligoclonal bands in cerebrospinal fluid (67 vs. 14%, p = 0.004). The only factor associated with poor outcome was presence of a spinal cord lesion on MRI without cervical involvement (56 vs. 14%, p = 0.02).Conclusion: Pediatric ATM patients presenting with clinical, radiological and laboratory features associated with multiple sclerosis (MS) are at risk for relapsing disease. In absence of these known MS risk factors at onset of disease these patients are at low risk for relapses. Only a minority of pediatric ATM patients in this cohort have a poor outcome. (C) 2020 The Japanese Society of Child Neurology. Published by Elsevier B.V.</p

Neurofibromatosis type 1 associated low grade gliomas:A comparison with sporadic low grade gliomas

AbstractNeurofibromatosis type 1 (NF1) is an autosomal dominant disorder, associated with a variable clinical phenotype including café-au-lait spots, intertriginous freckling, Lisch nodules, neurofibromas, optic pathway gliomas and distinctive bony lesions. NF1 is caused by a mutation in the NF1 gene, which codes for neurofibromin, a large protein involved in the MAPK- and the mTOR-pathway through RAS-RAF signalling.NF1 is a known tumour predisposition syndrome, associated with different tumours of the nervous system including low grade gliomas (LGGs) in the paediatric population. The focus of this review is on grade I pilocytic astrocytomas (PAs), the most commonly observed histologic subtype of low grade gliomas in NF1. Clinically, these PAs have a better prognosis and show different localisation patterns than their sporadic counterparts, which are most commonly associated with a KIAA1549:BRAF fusion.In this review, possible mechanisms of tumourigenesis in LGGs with and without NF1 will be discussed, including the contribution of different signalling pathways and tumour microenvironment. Furthermore we will discuss how increased understanding of tumourigenesis may lead to new potential targets for treatment

Acute flaccid myelitis and Guillain-Barré syndrome in children: A comparative study with evaluation of diagnostic criteria

Background and purpose: Differentiation between acute flaccid myelitis (AFM) and Guillain-Barré syndrome (GBS) can be difficult, particularly in children. Our objective was to improve the diagnostic accuracy by giving recommendations based on a comparison of clinical features and diagnostic criteria in children with AFM or GBS. Methods: A cohort of 26 children with AFM associated with enterovirus D68 was compared to a cohort of 156 children with GBS. The specificity of the Brighton criteria, used for GBS diagnosis, was evaluated in the AFM cohort and the specificity of the Centers for Disease Control and Prevention (CDC) AFM diagnostic criteria in the GBS cohort. Results: Children with AFM compared to those with GBS had a shorter interval between onset of weakness and nadir (3 vs. 8 days, p < 0.001), more often had asymmetric limb weakness (58% vs. 0%, p < 0.001), and less frequently had sensory deficits (0% vs. 40%, p < 0.001). In AFM, cerebrospinal fluid leukocyte counts were higher, whereas protein concentrations were lower. Spinal cord lesions on magnetic resonance imaging were only found in AFM patients. No GBS case fulfilled CDC criteria for definite AFM. Of the AFM cases, 8% fulfilled the Brighton criteria for GBS, when omitting the criterion of excluding an alternate diagnosis. Conclusions: Despite the overlap in clinical presentation, we found distinctive early clinical and diagnostic characteristics for differentiating AFM from GBS in children. Diagnostic criteria for AFM and GBS usually perform well, but some AFM cases may fulfill clinical diagnostic criteria for GBS. This underlines the need to perform diagnostic tests early to exclude AFM in children suspected of atypical GBS.The Prinses Beatrix Spierfonds funded the PhD project of J.R. on GBS in children (project number: W.OR12-04)S

Twenty-nine Cases of Enterovirus-D68-associated Acute Flaccid Myelitis in Europe 2016 A Case Series and Epidemiologic Overview

Background: Enterovirus-D68 (EV-D68) is a respiratory virus within the genus Enterovirus and the family of Picornaviridae. Genetically, it is closely related to rhinovirus that replicates in the respiratory tract and causes respiratory disease. Since 2014, EV-D68 has been associated with the neurologic syndrome of acute flaccid myelitis (AFM). Methods: In October 2016, questionnaires were sent out to a European network including 66 virologists and clinicians, to develop an inventory of EVD68- associated AFM cases in Europe. Clinical and virologic information of case patients was requested. In addition, epidemiologic information on EV testing was collected for the period between March and October 2016. Results: Twenty-nine cases of EV-D68-associated AFM were identified, from 12 different European countries. Five originated from France, 5 from Scotland and 3 each from Sweden, Norway and Spain. Twenty-six were children (median age 3.8 years), 3 were adults. EV-D68 was detected in respiratory materials (n = 27), feces (n = 8) and/or cerebrospinal fluid (n = 2). Common clinical features were asymmetric flaccid limb weakness, cranial nerve deficits and bulbar symptoms. On magnetic resonance imaging, typical findings were hyperintensity of the central cord and/or brainstem; low motor amplitudes with normal conduction velocities were seen on electromyography. Full clinical recovery was rare (n = 3), and 2 patients died. The epidemiologic data from 16 European laboratories showed that of all EV-D68-positive samples, 99% was detected in a respiratory specimen. Conclusions: For 2016, 29 EV-D68-related AFM cases were identified in mostly Western Europe. This is likely an underestimation, because case identification is dependent on awareness among clinicians, adequate viral diagnostics on respiratory samples and the capability of laboratories to type EVs

Ursinus College Alumni Journal, November 1964

President\u27s letter • Charles David Mattern, 1907-1964: With tributes from some of his colleagues • Professor without portfolio: A portrait of the Rev. John Henry Augustus Bomberger, D. D., founder and first president of Ursinus College and School of Theology • The contemporary French literary scene • Quarter-century change . . . decade planning • Student facilities building construction moves steadily toward completion by mid-\u2765 • Joseph Chapline, \u2742, former computer expert builds organs - tells how and why • Larry Koch, \u2762, advances with Western Electric • Schellhase saga • Insurance executive, author - historian, two new members of Ursinus Board • The 1964 European travel seminar • Yale Press to publish Dr. Foster\u27s volumes • Four Ursinus alumni attend campus conference for furloughed missionaries • Pancoast, \u2737 elected to Pennsylvania House of Representatives • Collegeville comes to life as Ursinus students return • Founders Day focus on distinguished alumni • Remarks presenting portrait of President of Ursinus Board • Gutenberg Bible reproductions presented by Henry Pfeiffer, \u2748 • Loyalty Fund report: October 10, 1964 • Sports victories, crowning of Queen Jeanne, feature 1964 Homecoming Day at Ursinus • Twenty-three bear cubs in Ursinus freshman class • Frederick Wentz named college business manager • Another John H. A. Bomberger • Alumni news and notes • Weddings • Births • Necrology • Former Dean dead at 83 • Vice-president of directors dies unexpectedly November 1 • Former board member dies • Ursinus Women\u27s Club luncheon December 5 • Chef Colameco hurt in railroad wreck • You need a will . . . and Ursinus needs to be rememberedhttps://digitalcommons.ursinus.edu/alumnijournal/1081/thumbnail.jp