Kinetics study of immunological response to Clostridium botulinum toxin

Circular RNAs in the Regulation of Oxidative Stress

Oxidative stress caused by an imbalance between the production and elimination of reactive metabolites and free radicals can lead to the development of a variety of diseases. Over the past years, with the development of science and technology, circular RNA (circRNA) has been found to be closely associated with oxidative stress, which plays an important role in the process of oxidative stress. Currently, the understanding of circRNAs in the mechanism of oxidative stress is limited. In this review, we described the relationship between oxidative stress and circRNAs, the circRNAs related to oxidative stress, and the role of circRNAs in promoting or inhibiting the occurrence and development of diseases associated with the oxidative stress system.

The use of botulinum toxin in pediatric disorders

Botulinum toxins have an exciting and important role in treating the child with hypertonia. The guidelines presented in this article are those that have been published representing the safe use of botulinum toxins in children. Experience and a decade of research have provided the framework for using botulinum toxins in decreasing deformity and promoting function. In children, a window of opportunity exists with botulinum toxin that allows improved motor control and elongation of shortened muscles. Although 3 to 4 months in an adult life is short, for a child it is a relatively greater proportion of their life experience and may be long enough for skill development. The improvement noted in function after botulinum toxin use is facilitated by comprehensive rehabilitation. The pediatric physiatrist has a unique role in the management of children with cerebral palsy and other conditions with hypertonia. Their knowledge and training reflect an understanding of anatomy and development that allows accurate evaluation of specific functional problems in children related to hypertonia. The pediatric physiatrist has experience in localization of muscles by EMG, nerve stimulation, and surface anatomy. Although many other physicians inject botulinum toxins, goal-directed management is the cornerstone to the physiatrist's thinking and treatment plan. Orthopedic surgery ultimately may be the intervention of choice if persistent contracture or progression of contractures occurs. Working in collaboration with an orthopedist identifies the timing of optimal surgical intervention for alignment. For persistent and severe hypertonia, the treatment team includes a neurosurgeon. All options for spasticity, such as selective posterior rhizotomy and intrathecal baclofen, should be considered. Re-evaluation of the child after selective dorsal rhizotomy or intrathecal baclofen is appropriate and should be discussed with therapists for focal intervention. Communication between members of the team and the family is desirable and frequently is one of the major contributions of the pediatric physiatrist. For children with focal hypertonia, botulinum toxins offer a dramatic but temporary repeatable change that affects rehabilitation. Research rapidly has captured the positive effect of the toxins on impairment and functional limitations. Not to be overlooked are outcomes related to quality of life. The long-term use of botulinum toxins and the role the toxins play throughout the life span of the person with a childhood hypertonic disorder are yet to be determined.

Cervical dystonia pathophysiology and treatment options

Dystonia is a syndrome of sustained involuntary muscle contractions, frequently causing twisting and repetitive movements or abnormal posturing. Cervical dystonia (CD) is a form of dystonia that involves neck muscles. However, CD is not the only cause of neck rotation. Torticollis may be caused by orthopaedic, musculofibrotic, infectious and other neurological conditions that affect the anatomy of the neck, and structural causes. It is estimated that there are between 60,000 and 90,000 patients with CD in the US. The majority of the patients present with a combination of neck rotation (rotatory torticollis or rotatocollis), flexion (anterocollis), extension (retrocollis), head tilt (laterocollis) or a lateral or sagittal shift. Neck posturing may be either tonic, clonic or tremulous, and may result in permanent and fixed contractures. Sensory tricks ('geste antagonistique') often temporarily ameliorate dystonic movements and postures. Commonly used sensory tricks by patients with CD include touching the chin, back of the head or top of the head. Patients with CD are classified according to aetiology into two groups: primary CD (idiopathic--may be genetic or sporadic) or secondary CD (symptomatic). Patients with primary CD have no evidence by history, physical examination or laboratory studies (except primary dystonia gene) of any secondary cause for the dystonic symptoms. CD is a part of either generalised or focal dystonic syndrome which may have a genetic basis, with an identifiable genetic association. Secondary or symptomatic CD may be caused by central or peripheral trauma, exposure to dopamine receptor antagonists (tardive), neurodegenerative disease, and other conditions associated with abnormal functioning of the basal ganglia. In the majority of patients with CD, the aetiology is not identifiable and the disorder is often classified as primary. Unless the aetiological investigation reveals a specific therapeutic intervention, therapy for CD is symptomatic. It includes supportive therapy and counselling, physical therapy, pharmacotherapy, chemodenervation [botulinum toxin (BTX), phenol, alcohol], and central and peripheral surgical therapy. The most widely used and accepted therapy for CD is local intramuscular injections of BTX-type A. Currently, both BTX type A and type B are commercially available, and type F has undergone testing. Pharmacotherapy, including anticholinergics, dopaminergic depleting and blocking agents, and other muscle relaxants can be used alone or in combination with other therapeutic interventions. Surgery is usually reserved for patients with CD in whom other forms of treatment have failed.

Pharmacologic characterization of botulinum toxin for basic science and medicine

The use of Botulinum neurotoxin (BoNT) is increasing in both clinical and basic science. Clinically, intramuscular injection of nanogram quantities of BoNT is fast becoming the treatment of choice for a spectrum of disorders including movement disorders such as torticollis, blepharospasm, Meige Disease, and hemifacial spasm (Borodic et al., 1991, 1994a; Jankovic and Brin, 1991; Clarke, 1992). Neuroscientists are using BoNTs as tools to develop a better understanding of the mechanisms underlying the neurotransmitter release process. Consequently, our ability to accurately and reliably quantify the biologic activity of botulinum toxin has become more important than ever. The accurate measurement of the pharmacologic activity of BoNTs has become somewhat problematic with the most significant problems occurring with the clinical use of the toxins. The biologic activity of BoNTs has been measured using a variety of techniques including assessment of whole animal responses to in vitro effects on neurotransmitter release. The purpose of this review is to examine the approaches employed to characterize, quantify and investigate the actions of the BoNTs and to provide a guide to aid investigators in determining which of these methods is most appropriate for their particular application or use.

Human immune response to botulinum pentavalent (ABCDE) toxoid determined by a neutralization test and by an enzyme-linked immunosorbent assay

To determine the immune status of persons receiving botulinum pentavalent (ABCDE) toxoid and to evaluate the effectiveness of the vaccine, we surveyed immunized individuals for neutralizing antibodies to type A and to type B botulinum toxins. After the primary series of three immunizations administered at 0, 2, and 12 weeks, 21 of 23 persons tested (91%) had a titer for type A that was greater than or equal to 0.08 international units (IU)/ml, and 18 (78%) had a titer for type B of greater than or equal to 0.02 IU/ml. (One international unit is defined as the amount of antibody neutralizing 10,000 mouse 50% lethal doses of type A or B botulinum toxin). Just before the first annual booster, 10 of 21 (48%) and 14 of 21 (67%) people lacked a detectable titer for type A and for type B, respectively. After the first booster, all individuals tested had a demonstrable titer to both types A and B. Of 77 persons who had previously received from one to eight boosts of the toxoid, 74 (96%) had an A titer of greater than or equal to 0.25 IU/ml and would not require an additional booster, according to the recommendations of the Centers for disease Control. However, only 44 of 77 (57%) had a B titer of greater than or equal to 0.25 IU/ml. In each group by booster number, even the group having had eight boosts, at least one person would require reimmunization on the basis of B titer. There was a wide range of antibody levels among individuals at the same point in the immunization scheme. Results from an enzyme linked immunosorbent assay, with purified type A or type B neurotoxin as the capture antigen, were compared with neutralization test results on 186 serum samples for type A and 168 samples for type B. Statistically, the correlation coefficients for results from the two assays were high (r = 0.69, P < 0.0001, for type A and r = 0.77, P < 0.0001, for type B). However, due to the wide dispersion of values obtained, using enzyme-linked immunosorbent assay results to predict neutralizing antibody levels is unwarranted.