Botulinum toxin

Production of monoclonal antibodies against botulinum neurotoxin in Nicotiana benthamiana

Botulism is a fatal neurologic disease caused by the botulinum toxin (BoNT) produced by Clostridium botulinum. It is a rare but highly toxic disease with symptoms, such as cramps, nausea, vomiting, diarrhea, dysphagia, respiratory failure, muscle weakness, and even death. Currently, two types of antitoxin are used: equine-derived heptavalent antitoxin and human-derived immunoglobulin (BabyBIG®). However, heptavalent treatment may result in hypersensitivity, whereas BabyBIG®, has a low yield. The present study focused on the development of three anti-BoNT monoclonal antibodies (mAbs), 1B18, C25, and M2, in Nicotiana benthamiana. The plant-expressed mAbs were purified and examined for size, purity and integrity by SDS-PAGE, western blotting and size-exclusion chromatography. Analysis showed that plant-produced anti-BoNT mAbs can fully assemble in plants, can be purified in a single purification step, and mostly remain as monomeric proteins. The efficiency of anti-BoNT mAbs binding to BoNT/A and B was then tested. Plant-produced 1B18 retained its ability to recognize both mBoNT/A1 and ciBoNT/B1. At the same time, the binding specificities of two other mAbs were determined: C25 for mBoNT/A1 and M2 for ciBoNT/B1. In conclusion, our results confirm the use of plants as an alternative platform for the production of anti-BoNT mAbs. This plant-based technology will serve as a versatile system for the development botulism immunotherapeutics.

Native botulinum toxin type A vs. redesigned botulinum toxins in pain: What did we learn so far?

Driven by the clinical success of botulinum toxin serotype A (BoNT/A) and the need for improved chronic pain management, researchers attempted to develop re-designed botulinum toxin (BoNT)-based molecules as novel analgesics. Various recombinant protein expression strategies including retargeted binding domains, and chimeric toxins combining different serotypes were tested to improve BoNT/A therapeutic safety margin and expand its efficacy. The aim of this review is to re-evaluate the current design strategies for recombinant BoNT-based molecules for pain treatment, compares their analgesic profile against the native BoNT/A, as well as to discuss the main strengths and potential weaknesses of reported approaches.

Analysis of Breast Milk Samples in Lactating Women After Undergoing Botulinum Toxin Injections for Facial Rejuvenation: A Pilot Study

Abstract Background: There are little data on the risk to a breastfeeding infant after facial botulinum toxin injections to the mother. Objective: To detect the presence of botulinum toxin in breast milk from lactating subjects treated with facial botulinum toxin injections, as measured by enzyme-linked immunosorbent assay (ELISA). Methods: For this pilot study, lactating women were injected with standardized facial botulinum toxin type A (BTXA) (range 40-92 U). Collected breast milk samples over 5 days were analyzed for the presence of botulinum toxin. Exclusion criteria included (1) lactating women still using their breast milk for their infant, (2) muscular disorders, (3) any medication that could interfere with neuromuscular function, (4) uncontrolled systemic disease, (5) pregnant, and (6) neuromodulator injection in the past 90 days. Results: Four lactating women were recruited. Eight samples had no BTXA detected, whereas 8 of the 16 total had detectible amounts, which were well below the reported lethal oral dose for an infant. Conclusion: Although the exclusion of lactating women from receiving cosmetic botulinum toxin injections is out of an abundance of caution to the theoretical risk to the infant, this study helps support the notion that facial botulinum toxin injections do not warrant an interruption in breastfeeding. Further studies with larger sample sizes are needed.

New and Future Developments in Neurotoxins

BACKGROUND

There are 7 known serotypes of botulinum neurotoxins (A through G). Currently, commercially available toxins are those in serotypes A and B. This paper will discuss new toxins on the horizon, developments in prolonging and shortening the duration of outcomes, and novel therapeutic indications on the horizon.

OBJECTIVE

To provide insight into new toxins and new therapeutic modalities surrounding toxins on the horizon.

METHODS

The authors have reviewed the relevant literature and shared their insights and opinions as to future developments in toxin research and potential clinical applications.

CONCLUSION

Botulinum neurotoxin type E's faster onset and shorter duration of effect represent true clinical differentiators. Future development of botulinum neurotoxin type E for aesthetic and therapeutic uses will be in areas where fast onset and short duration of effect are desirable. Current challenges with neuromodulators include the need for frequent treatments and lack of reversal agents. Agents to address both challenges and novel indications, including inhibition of melanogenesis, are being developed.

Evaluation of efficacy and safety of Botulinum toxin-A injection at three deferent sites in treatment of premature ejaculation

BACKGROUND

Premature ejaculation (PE) is a common sexual problem, resulting in adverse effects on the quality of life, of both the patient and the partner. The idea of muscular contraction inhibition during the ejection phase of ejaculation by Botulinum toxin-A injection may delay ejaculation.

AIM OF STUDY

This study was performed to assess the efficacy and safety of Botulinum toxin-A injection in PE treatment.

MATERIAL AND METHODS

This study included 45 married male patients diagnosed with primary PE. All included patients were injected with 75 units of Dysport equal efficacy of 25 units of Botulinum toxin-A (Botox) into three sites: the root of the penis (Group 1), glans penis (Group 2), and each side of the ischiocavernosus muscle (Group 3). All patients were subjected to an assessment of intravaginal ejaculation latency time (IELT) using a stopwatch and answering the Premature Ejaculation Diagnostic Tool (PEDT) Questionnaire before and after treatment.

RESULTS

There was a statistically significant improvement in IELT after treatment in all groups. The most significant improvement was shown in Group 3 (average 108% increase), followed by Group 1 (74%) and Group 2 (40%), respectively. There was a positive correlation between age and the improvement in improved IELT. There was a statistically significant improvement in PEDTq scores in Group 1 and Group 3.

CONCLUSION

Botulinum toxin-A injection into the root of the penis and ischiocavernosus muscle could be recommended in the treatment of premature ejaculation.

Pediatric Salivary Gland Pathology

Benign and malignant salivary gland disorders are uncommon in the pediatric population; however, these can be frequently seen in pediatric otolaryngology or oral and maxillofacial surgery practices. The astute clinician should be aware of the clinical presentation, diagnosis, and management options for common inflammatory, infectious, benign, and malignant disorders of salivary glands.

Evaluation of the Patient with Facial Palsy: A Multidisciplinary Approach

This article aims to provide an overview of the management of facial palsy within a multidisciplinary team setting and discusses considerations used to develop patient-specific management plans. The national landscape of facial function services is also discussed including suggestions on what may enable a more equitable and sustainable service for the future.

Delayed onset post-traumatic wound botulism

A 41-year-old man developed rapidly progressive cranial neuropathies and muscle weakness followed by respiratory failure, requiring ventilation support. On examination, there was marked bilateral ptosis and ophthalmoplegia with bulbar, neck and proximal upper limb weakness. He had a recent open left humeral fracture that eventually required amputation. Despite immunoglobulin therapy, his progressive weakness continued. Multiple investigation results were inconclusive. Eventually, botulinum type A toxin was found positive, by which time the therapeutic window for antitoxin had passed. He continued on supportive management and was treated for concomitant infections and nosocomial illnesses. He was subsequently weaned from respiratory support and has made a good neurological recovery.

The Effect of Botulinum Toxin A on the NADPH Oxidase System and Ischemia-Reperfusion Injury

BACKGROUND

Despite the increasing popularity of various materials for ischemia-reperfusion (I/R) injury mitigation, research on botulinum toxin type A (BoNTA) remains limited. This study assesses BoNTA's efficacy in protecting flaps from I/R injury by inhibiting the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system and reducing reactive oxygen species (ROS) production.

METHODS

Seventy-six Sprague-Dawley rats were studied. We examined the effects of BoNTA on superoxide production in four rats using a lucigenin-enhanced chemiluminescence assay (LECL). Another group of 60 rats had their superficial inferior epigastric artery (SIEA) flaps treated with either BoNTA or saline and clamped for 0, 1, and 4 hours before reperfusion. Flap survival and histological outcomes were assessed five days post-operation. ROS production in SIEA flaps and femoral vessels was analyzed in 12 additional rats, post-I/R injury.

RESULTS

The LECL results showed that the BoNTA group had significantly lower superoxide production compared to controls, with notable reductions at 4 hours. While no significant differences were noted at the 0 and 1-hour marks, the 4-hour mark showed significant protective effects in BoNTA-treated groups. The survival rate was 90% for BoNTA-treated rats versus 60% for controls ( P = 0.028). Significant reductions in ROS were also observed in the 4-hour I/R group.

CONCLUSIONS

BoNTA effectively protects against I/R injury by inhibiting the NADPH oxidase system and reducing ROS levels. These results support further investigation into the specific mechanisms of NADPH oxidase inhibition by BoNTA and its potential clinical applications, given its safety profile.

CLINICAL RELEVANCE STATEMENT

The findings from the present study are expected to provide a basis for clinical studies regarding this use of BoNTA.

Five decades of the use of botulinum toxin in ophthalmology

Botulinum toxin (BoNT) has been known for over 50 years. It has conquered many areas of medicine and has become indispensable in contemporary medicine. Now, BoNT is used to treat at least 26 conditions in six medical specialties. Although the use of BoNT began in strabology, it became the gold standard for many ophthalmologic pathologies. The present review of the literature focuses on the use of BoNT in ophthalmology and treatment of the following conditions: blepharospasm, facial hemispasm, facial palsy, spastic entropion, strabismus, endocrine orbitopathy, convergence spasm, and facial trauma. We conclude that nearly half a century of experience in utilizing BoNT in ophthalmology ensured a satisfactory level of effectiveness and safety for patients with many pathologies. Areas of future research include the application of BoNT in new selected indications, the development of the route of application without injections, and the development of long-acting BoNT forms for patients who require repeated long-term treatment.

Evaluation of Botox treatment in patients with chronic scrotal pain: Protocol for a randomized double-blinded control trial

Background

Chronic scrotal pain is a common condition with a prevalence of 2.5-4.8% in male outpatients. Up to 40% of these patients report depressive symptoms and many feel isolated. Minimal invasive treatment is lacking, while spermatic cord injections of Botox® (BTX) have been proposed to offer long-term pain relief.

Study Design

This research protocol comprises a prospective multicentre, randomized, double-blinded clinical trial drawing patients from other urological departments in the region of Southern Denmark.

End Points

The primary end point will be reduction in pain evaluated by visual analogue score for pain at 3 months. Secondary end point will be length of effect of BTX injections along with changes in quality of life.

Patients and Methods

The study will include 50 patients for randomization to either spermatic cord block with 100 IE BTX or sterile saline. All patients will prior to randomization undergo physical examination and will be asked to fulfil multiple questionnaires regarding pain and impact in daily life, that is, (1) visual analogue score for pain, (2) quality of life (EQ-5D-5L), (3) Chronic Prostatitis Symptom Index (NIH-CPSI), (4) ICD-10 depression questionnaire (MDI), (5) Likert global assessment scale, and (6) International Index of Erectile Function questionnaire. Physical examination and fulfilment of the questionnaires will be repeated multiple times throughout the study period of 12 weeks. After this time point, patients will be unblinded, and the control arm will be given the opportunity of cross-over.

Image guided preoperative abdominal wall botox injection for large ventral hernia repair: A case series

This case series aims to explore the application of preoperative CT guided Botox injections in three different cases of abdominal wall reconstructions. Each of the three cases highlights the role of chemical component separation in achieving myofascial release and contributing to a successful surgical repair. The use of Botox in the preoperative planning of abdominal wall repair aims at creating a tension-free environment for midline closure and promoting an overall positive postoperative course for the patient. This case series presents as a valuable contribution to the different surgical approaches in abdominal wall reconstruction and the collaboration between Interventional Radiology and Surgery in treating such patients.

High-energy pacing inhibits slow-wave dysrhythmias in the small intestine

The motility of the gastrointestinal tract is coordinated in part by rhythmic slow waves, and disrupted slow-wave patterns are linked to functional motility disorders. At present, there are no treatment strategies that primarily target slow-wave activity. This study assessed the use of pacing to suppress glucagon-induced slow-wave dysrhythmias in the small intestine. Slow waves in the jejunum were mapped in vivo using a high-resolution surface-contact electrode array in pigs (n = 7). Glucagon was intravenously administered to induce hyperglycemia. Slow-wave propagation patterns were categorized into antegrade, retrograde, collision, pacemaker, and uncoupled activity. Slow-wave characteristics such as period, amplitude, and speed were also quantified. Postglucagon infusion, pacing was applied at 4 mA and 8 mA and the resulting slow waves were quantified spatiotemporally. Antegrade propagation was dominant throughout all stages with a prevalence of 55 ± 38% at baseline. However, glucagon infusion resulted in a substantial and significant increase in uncoupled slow waves from 10 ± 8% to 30 ± 12% (P = 0.004) without significantly altering the prevalence of other slow-wave patterns. Slow-wave frequency, amplitude, and speed remained unchanged. Pacing, particularly at 8 mA, significantly suppressed dysrhythmic slow-wave patterns and achieved more effective spatial entrainment (85%) compared with 4 mA (46%, P = 0.039). This study defined the effect of glucagon on jejunal slow waves and identified uncoupling as a key dysrhythmia signature. Pacing effectively entrained rhythmic activity and suppressed dysrhythmias, highlighting the potential of pacing for gastrointestinal disorders associated with slow-wave abnormalities.NEW & NOTEWORTHY Glucagon was infused in pigs to induce hyperglycemia and the resulting slow-wave response in the intact jejunum was defined in high resolution for the first time. Subsequently, with pacing, the glucagon-induced dysrhythmias were suppressed and spatially entrained for the first time with a success rate of 85%. The ability to suppress slow-wave dysrhythmias through pacing is promising in treating motility disorders that are associated with intestinal dysrhythmias.

Insights into membrane interactions and their therapeutic potential

Recent research into membrane interactions has uncovered a diverse range of therapeutic opportunities through the bioengineering of human and non-human macromolecules. Although the majority of this research is focussed on fundamental developments, emerging studies are showcasing promising new technologies to combat conditions such as cancer, Alzheimer's and inflammatory and immune-based disease, utilising the alteration of bacteriophage, adenovirus, bacterial toxins, type 6 secretion systems, annexins, mitochondrial antiviral signalling proteins and bacterial nano-syringes. To advance the field further, each of these opportunities need to be better understood, and the therapeutic models need to be further optimised. Here, we summarise the knowledge and insights into several membrane interactions and detail their current and potential uses therapeutically.

Assessing effects of Cannabis on various neuropathologies: A systematic review

Natural bioactives possess a wide range of chemical structures that can exert a plethora of pharmacological and toxicological actions, resulting in neuroprotection or neurotoxicity. These pharmacodynamic properties can positively or negatively impact human and animal global healthcare. Remarkably, Ayurvedic botanical Cannabis has been used worldwide by different ethnicities and religions for spiritual, commercial, recreational, nutraceutical, cosmeceutical, and medicinal purposes for centuries. Cannabis-based congeners have been approved by the United States of America's (USA) Food & Drug Administration (FDA) and other global law agencies for various therapeutic purposes. Surprisingly, the strict laws associated with possessing cannabis products have been mitigated in multiple states in the USA and across the globe for recreational use. This has consequently led to a radical escalation of exposure to cannabis-related substances of abuse. However, there is a lacuna in the literature on the acute and chronic effects of Cannabis and its congeners on various neuropathologies. Moreover, in the post-COVID era, there has been a drastic increase in the incidence and prevalence of numerous neuropathologies, leading to increased morbidity and mortality. There is an impending necessity for a safe, economically viable, multipotent, natural bioactive to prevent and treat various neuropathologies. The ayurvedic herb, Cannabis is one of the oldest botanicals known to humans and has been widely used. However, the comprehensive effect of Cannabis on various neuropathologies is not well established. Hence, this review presents effects of Cannabis on various neuropathologies.

Retrograde Cricopharyngeus Dysfunction, a New Motility Disorder: Single Center Case Series and Treatment Results

Background/Aims

Retrograde cricopharyngeus dysfunction (R-CPD) is a new clinical entity characterized by inability to belch and associated symptoms of loud gurgling noises, chest and/or abdominal pressure, abdominal bloating, and excessive flatulence. R-CPD can be treated with botulinum toxin (BT) injection in the upper esophageal sphincter. We hereby report patient demographics, symptomatology, and treatment results of a series of consecutive patients who presented at our center.

Methods

Data on 50 consecutive patients presenting with R-CPD were prospectively collected using a standardized questionnaire prior to, 1 month after treatment and at the end of follow-up. All patients were diagnosed using a set of clinical symptoms.

Results

Fifty patients (26 females) were included, median age was 27.5 years (range, 17-65). Median body mass index was 22.7 kg/m2 (range, 16.6-37.5). Inability to belch was present in all patients, > 90% of patients experienced gurgling noises and abdominal/chest discomfort as result of their condition. One month after injection of BT, 40.8% of patients experienced complete relief of symptoms, 24.5% good symptom improvement, 24.5% some symptom improvement and 10.2% no improvement. At median follow-up of 29 months (range, 3-50) post-treatment, 51.3% (n = 20/39) of patients reported persistent complete relief of symptoms, 12.8% good improvement of symptoms (n = 5/39), in 15.4% some improvement (6/39) and 20.5% loss of or no response (n = 8/39). Only minor and transient side effects were reported.

Conclusions

Our case series of 50 patients with R-CPD shows very good short-term and good long-term improvement of symptoms after injection of BT. These results are in line with previous studies.

Clinical Application of Botulinum Toxin A on Nasal Reconstruction with Expanded Forehead Flap for Asian Patients

BACKGROUND

Because of its unique advantages, frontal expansion has become a common tool for Asian nasal reconstruction, but it has the limitations of prolonging the duration and pain in the expansion area. Based on the fact that the denervation effect of botulinum toxin type A (BTX-A) has been widely used in the reconstruction of superficial organs, we hypothesized that BTX-A would shorten the length of nasal reconstruction sequence and alleviate the discomfort of patients.

METHODS

A comparative retrospective study was conducted of consecutive patients underwent sequential treatment of nasal reconstruction between June 2010 and July 2012. Data on demographics, BTX-A injection plan and expansion duration were collected and analyzed. Phased pain intensity outcomes were evaluated by visual analogue scale (VAS). Photographs were collected during the follow-up period.

RESULTS

Thirty patients were enrolled in the study; 15 (50%) with and 15 (50%) without BTX-A pre-injection. Demographic data were homogeneous. The duration of the observation group (BTX-A pretreated) (133.87 ± 13.64 days) was significantly shortened versus the control group (164.27 ± 14.08 days, P<0.001). At the initial stage, no significant difference was found in the VAS scores (P=0.64). At the medium stage, the VAS score of the observation group (2.07 ± 0.80) was significantly lower than the control group (3.00 ± 0.53, P<0.01). At the terminal stage, the VAS score of the observation group (1.93 ± 0.59) was significantly lower than the control group (2.73 ± 0.70) but with a narrower disparity.

CONCLUSION

Pre-injection of BTX-A is effective in shortening the duration of the expansion phase, as well as relieving the pain associated with expansion.

LEVEL OF EVIDENCE IV

The journal asks authors to assign a level of evidence to each article. For a complete description of Evidence-Based Medicine ratings, see the Table of Contents or the online Instructions for Authors at www.springer.com/00266 .

The effect of botulinum toxin A in children with non-neurogenic therapy-refractory dysfunctional voiding - A systematic review

INTRODUCTION

Dysfunctional voiding (DV) is a habitual voiding disorder caused by involuntary contraction or non-relaxation of the external urethral sphincter (EUS) during voiding. This contraction causes high post-void residuals (PVR), urinary incontinence and urinary tract infections (UTIs). Various treatments for DV are available, but some children do not respond. Intersphincteric botulinum toxin-A (BTX-A) may be a possible treatment for therapy-refractory children with DV.

OBJECTIVE

The aim of this systematic review is to summarize the effects and safety of intersphincteric BTX-A as a treatment for therapy-refractory DV in children.

METHODS

A systematic search in Embase, MEDLINE, Cochrane, and Web of Science databases was performed. Studies reporting on the usage of intersphincteric BTX-A as a treatment for DV in children were included. Data on PVR, maximum flow rate (Qmax), repeat injections and complications were extracted.

RESULTS

From a total of 277 articles, five cohort studies were identified, reporting on 78 children with DV of whom 53 were female (68 %) and 25 were male (32 %). Sample sizes ranged from ten to twenty patients. Mean or median age at the time of intervention ranged from 8 to 10.5 years. Meta-analysis could not be performed due to lack of data. The narrative synthesis approach was therefore used to summarize the results. All studies showed significant decrease in PVR after BTX-A injection. Three studies showed a 33-69 % improvement on incontinence after BTX-A injection. Less UTIs were reported after treatment. A temporary increase in incontinence, UTIs and transitory numbness to the gluteus muscle were reported as side-effects.

CONCLUSIONS

BTX-A could be a safe and effective treatment option for therapy-refractory DV in children by reducing PVR, UTIs and incontinence. Hereby, the synergistic effect of BTX-A and urotherapy should be emphasized in future management. Furthermore, this study identified gaps in current knowledge that are of interest for future research.

Belgian consensus guideline on the management of anal fissures

Introduction

Acute and chronic anal fissures are common proctological problems that lead to relatively high morbidity and frequent contacts with health care professionals. Multiple treatment options, both topical and surgical, are available, therefore evidence-based guidance is preferred.

Methods

A Delphi consensus process was used to review the literature and create relevant statements on the treatment of anal fissures. These statements were discussed and modulated until sufficient agreement was reached. These guidelines were based on the published literature up to January 2023.

Results

Anal fissures occur equally in both sexes, mostly between the second and fourth decades of life. Diagnosis can be made based on cardinal symptoms and clinical examination. In case of insufficient relief with conservative treatment options, pharmacological sphincter relaxation is preferred. After 6-8 weeks of topical treatment, surgical options can be explored. Both lateral internal sphincterotomy as well as fissurectomy are well-established surgical techniques, both with specific benefits and risks.

Conclusions

The current guidelines for the management of anal fissures include recommendations for the clinical evaluation of anal fissures, and their conservative, topical and surgical management.

Hyperdiluted Botulinum Toxin and Intense Pulsed Light Treatment: A Case Series to Illustrate a Novel Protocol for Hypertrophic Scar Reduction

Hypertrophic scars can have significant and far-reaching effects on patients that range from itching to creating difficulty with mobility, all of which can negatively impact the individual's quality of life. A recent study showed that many patients with recent scars report pain, burning, pruritus, erythema, in combination with psychological difficulties that impact bodily movement, choice of clothing, and participation in leisure activities. Botulinum toxin Type A (BoNTA) and intense pulsed light (IPL) have shown promise in treating such scars. We propose a novel treatment protocol involving a 4-week intervention with hyperdiluted BoNTA injections and supplemental treatment with IPL for erythema, and a 6-month scar scale assessment and photographic documentation that occurs before and 6 months after treatment. We report four cases where using hyperdiluted BoNTA, either alone or in conjunction with IPL, substantially reduced scar size, improved overall scar appearance, and diminished erythema in areas on the face and the breasts. Although this report suggests that a schedule of alternating treatments with BoNTA and IPL may be beneficial in reducing scar size and enhancing appearance, further research is necessary to better understand the most effective dosages, the relationship between BoNTA and IPL, and the optimal management of scarring.

Treatment of Full Eyelid Ptosis Following Botox Injection: A Case Report

We report the case of a 24-year-old woman who was referred to one of the authors' clinics after six days of botulinum toxin type A injection to treat dynamic lines on her forehead, glabella complex, and crow's feet area. Her first esthetic injection was done by another colleague elsewhere in a different clinic. Her main complaint was full eyelid ptosis, which started four days after her treatment and continued to aggravate until the time she sought our help. We treated it with another dose of botulinum toxins. The patient started to notice a gradual improvement in her eyelid five days after our injection, so on day 14th, her eyelid was very closely back to normal opening; complete recovery was achieved. Ptosis due to botulinum toxin injection was surprisingly and successfully reversed in our article by a second dose of botulinum toxins. This suggests that this management successfully treats such cases and can deliver a beneficial reversal option for practitioners and their patients. The case report concludes that ptosis should be promptly evaluated and treated through a multimodal approach.

From Toxin to Treatment: A Narrative Review on the Use of Botulinum Toxin for Autonomic Dysfunction

Since its regulatory approval over a half-century ago, botulinum toxin has evolved from one of the most potent neurotoxins known to becoming routinely adopted in clinical practice. Botulinum toxin, a highly potent neurotoxin produced by Clostridium botulinum, can cause botulism illness, characterized by widespread muscle weakness due to inhibition of acetylcholine transmission at neuromuscular junctions. The observation of botulinum toxin's anticholinergic properties led to the investigation of its potential benefits for conditions with an underlying etiology of cholinergic transmission, including autonomic nervous system dysfunction. These conditions range from disorders of the integument to gastrointestinal and urinary systems. Several formulations of botulinum toxin have been developed and tested over time, significantly increasing the availability of this treatment for appropriate clinical use. Despite the accelerated and expanded use of botulinum toxin, there lacks an updated comprehensive review on its therapeutic use, particularly to treat autonomic dysfunction. This narrative review provides an overview of the effect of botulinum toxin in the treatment of autonomic dysfunction and summarizes the different formulations and dosages most widely studied, while highlighting reported outcomes and the occurrence of any adverse events.

Adverse effect of botulinum toxin-A injections on mandibular bone: A systematic review and meta-analysis

INTRODUCTION

Botulinum toxin-A (BTX) is a potent neurotoxin that is emerging in the scope of dental practice for its ability to temporarily paralyse musculature and reduce hyperfunction. This may be desirable in diseases/disorders associated with hyperactive muscles such as the muscles of mastication, most implicated in painful temporomandibular disorders (TMDs). The use of BTX extends beyond its indications with off-label use in TMD's and other conditions, while potential adverse effects remain understudied. BTX is well-established hindlimb paralysis model in animals leading to significant bone loss with underlying mechanisms remaining unclear. The objective of this study is to systematically review the literature for articles investigating changes in mandibular bone following BTX injections and meta-analyse available data on reported bone outcomes.

METHODS

Comprehensive search of Medline, Embase and Web of Science retrieved 934 articles. Following the screening process, 36 articles in animals and humans were included for quantitative synthesis. Articles in human individuals (6) and three different animal species (14) presented mandibular bone outcomes that were included in the meta-analysis.

RESULTS

The masseter and temporalis muscles were frequently injected across all species. In humans, we observe a decrease of about 6% in cortical thickness of mandibular regions following BTX injection with no evident changes in either volume or density of bone structures. In animals, bone loss in the condylar region is significantly high in both cortical and trabecular compartments.

DISCUSSION

Our analysis supports the concept of BTX-induced bone-loss model in animal mandibles. Further, bone loss might be confined to the cortical compartments in humans. Most studies did not address the reality of repeated injections and excessive dosing, which occur due to the reversible action of BTX. More rigorous trials are needed to draw a full picture of potential long-term adverse effects on bone.

Botulinum Toxin for the Management of Parkinson's Disease: A Systematic Review

Parkinson's disease (PD) is a terminal, debilitating neurodegenerative disorder typically affecting individuals over 60. It is associated with various conditions that drastically affect the patient's quality of life (QoL). Although there is no cure for PD, its symptoms can be significantly improved and even resolved through different treatments. Mainstay treatments for PD include levodopa combined with carbidopa, dopamine agonists, and even deep brain stimulation (DBS) of the subthalamic nucleus. New treatment methods have emerged, such as botulinum toxin (BoNT), which further improve symptoms and, thus, the QoL of patients with PD. Botulinum toxin is a potent neurotoxin produced by Clostridium botulinum that typically causes descending paralysis by suppressing acetylcholine secretion. Serotypes used to treat various disorders include serotype A (BoNT-A) and serotype B (BoNT-B). This paper aims to evaluate the outcomes of BoNT injection on different symptoms associated with PD. An extensive review using PubMed, ScienceDirect, and ProQuest articles concerning 'botulinum toxin and Parkinson's disease' was done per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, resulting in 23,803 articles. After applying strict inclusion and exclusion criteria, the total number of articles was finally 41. The results showed that movement disorders were a common occurrence in PD, consisting of tremors, dystonia, and freezing of gait (FOG), with tremors being the most common symptom. Tremors and dystonia were significantly improved following BoNT-A, correlating with significant improvements in various scales subjectively and objectively evaluating the symptoms and QoL. In contrast, FOG was not significantly improved by either BoNT-A or BoNT-B. Pain is associated with movement disorders such as PD and was the primary indication for the administration of BoNT; studies found pain and QoL were significantly improved following BoNT injection. Quality of life can also be affected by sialorrhea and overactive bladder, which often occur as the disease progresses. Injections of BoNT-A and BoNT-B were shown to significantly improve saliva production, flow rate, drooling frequency, voiding frequency, and urinary urge incontinence. Across all studies analyzed, it is evident that BoNT may have a significant effect on improving the QoL of patients suffering from PD. While research continues to find a cure or stop the progression of PD, it remains critical to continue focusing on improving patients' QoL. Future research should evaluate whether BoNT can be used to successfully treat other symptoms of PD, such as epiphora or constipation.

Industrial Production and Therapeutic Application of Botulinum Neurotoxin: The Role of C. botulinum Type A

Botulinum neurotoxin has remarkably transitioned from a food safety hazard and biological warfare to an effective therapeutic drug. Currently, botulinum neurotoxins have seven serotypes (BoNT/A-G) in the form of protein complexes produced by Clostridium, a gram-positive and sporeforming bacteria. The conversion of toxins into useful drug substances of choice using the biotechnological process is tremendously increasing. Recent studies have shown that Botulinum neurotoxin-A (BoNT/A) has different biological activities and potencies in experimental and clinical conditions. They also indicate that the manufacturing process influences the potency and efficacy of BoNT/A drugs. Thus, this review focuses on the following criteria: detailed Fed-batch operation that includes the upstream and downstream processing of BoNT/A, the underlying mechanism behind the neurotoxic effect, and commercially available FDA-approved BoNT/A products and their therapeutic uses. Still, some research gaps exist in the mechanism for the treatment of psychiatric disorders.

Pathogenicity and virulence of Clostridium botulinum

Clostridium botulinum, a polyphyletic Gram-positive taxon of bacteria, is classified purely by their ability to produce botulinum neurotoxin (BoNT). BoNT is the primary virulence factor and the causative agent of botulism. A potentially fatal disease, botulism is classically characterized by a symmetrical descending flaccid paralysis, which is left untreated can lead to respiratory failure and death. Botulism cases are classified into three main forms dependent on the nature of intoxication; foodborne, wound and infant. The BoNT, regarded as the most potent biological substance known, is a zinc metalloprotease that specifically cleaves SNARE proteins at neuromuscular junctions, preventing exocytosis of neurotransmitters, leading to muscle paralysis. The BoNT is now used to treat numerous medical conditions caused by overactive or spastic muscles and is extensively used in the cosmetic industry due to its high specificity and the exceedingly small doses needed to exert long-lasting pharmacological effects. Additionally, the ability to form endospores is critical to the pathogenicity of the bacteria. Disease transmission is often facilitated via the metabolically dormant spores that are highly resistant to environment stresses, allowing persistence in the environment in unfavourable conditions. Infant and wound botulism infections are initiated upon germination of the spores into neurotoxin producing vegetative cells, whereas foodborne botulism is attributed to ingestion of preformed BoNT. C. botulinum is a saprophytic bacterium, thought to have evolved its potent neurotoxin to establish a source of nutrients by killing its host.

Mechanism and clinical use of botulinum neurotoxin in head and facial region

PURPOSE

Botulinum neurotoxin (BoNT) is a biological toxin produced by Clostridium botulinum. BoNT is a potent toxin extensively used in therapeutic interventions. This review provides an updated overview of the mechanisms of action and clinical applications of BoNT in head and facial region.

STUDY SELECTION

MEDLINE/PubMed searches were conducted using the terms "botulinum neurotoxin" and "dentistry" along with a combination of other related terms. In addition, studies were manually selected from reference lists of the selected articles.

RESULTS

The Food and Drug Administration in the United States initially approved BoNT to treat strabismus, blepharospasm, and hemifacial spasms. The use of BoNT in dermatology and cosmetics has been widely established and has created a revolution in these fields. Over the years, its applications in various medical specialties have expanded widely. Owing to its safety, efficacy, and long duration of action, it is well-accepted by patients. BoNT/A and BoNT/B are widely used in clinical practice. Several off-label uses of BoNT in the dental fraternity have yielded promising results. We have elaborated on the speculated mechanism of action, dosage, effective sites of injection, and adverse effects of each therapeutic application. The various clinical indications for BoNT include bruxism, myofascial pain, temporomandibular joint dislocation, hemifacial pain, orofacial dystonia, facial paralysis, chronic migraine, and trigeminal neuralgia.

CONCLUSIONS

BoNT is a safe treatment that can be used effectively, provided that the clinician has adequate knowledge regarding the mechanism, injection techniques, and local and systemic side effects and that it is administered cautiously and purposefully.

Ideal Injection Points for Botulinum Neurotoxin for Pectoralis Minor Syndrome: A Cadaveric Study

Pectoralis Minor Syndrome (PMS) causes significant discomfort due to the compression of the neurovascular bundle within the retropectoralis minor space. Botulinum neurotoxin (BoNT) injections have emerged as a potential treatment method; however, their effectiveness depends on accurately locating the injection site. In this study, we aimed to identify optimal BoNT injection sites for PMS treatment. We used twenty-nine embalmed and eight non-embalmed human cadavers to determine the origin and intramuscular arborization of the pectoralis minor muscle (Pm) via manual dissection and Sihler's nerve staining techniques. Our findings showed the Pm's origin near an oblique line through the suprasternal notch, with most neural arborization within the proximal three-fourths of the Pm. Blind dye injections validated these results, effectively targeting the primary neural arborized area of the Pm at the oblique line's intersection with the second and third ribs. We propose BoNT injections at the arborized region within the Pm's proximal three-fourths, or the C region, for PMS treatment. These findings guide clinicians towards safer, more effective BoNT injections.

Systematic Review on Botulinum Toxin Injections as Diagnostic or Therapeutic Tool in Thoracic Outlet Syndrome

BACKGROUND

The optimal diagnostic and treatment algorithm for patients with suspected thoracic outlet syndrome (TOS) remains challenging. Botulinum toxin (BTX) muscle injections have been suggested to shrink muscles in the thoracic outlet reducing neurovascular compression. This systematic review evaluates the diagnostic and therapeutic value of BTX injections in TOS.

METHODS

A systematic review of studies reporting BTX as a diagnostic or therapeutic tool in TOS (or pectoralis minor syndrome as TOS subtype) was conducted in PubMed, Embase, and CENTRAL databases on May 26, 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was followed. Primary end point was symptom reduction after primary procedure. Secondary end points were symptom reduction after repeated procedures, the degree of symptom reduction, complications, and duration of clinical effect.

RESULTS

Eight studies (1 randomized controlled trial [RCT], 1 prospective cohort study, and 6 retrospective cohort studies) were included reporting 716 procedures in at least 497 patients (at minimum 350 primary and 25 repeated procedures, residual unclear) diagnosed with presumably only neurogenic TOS. Except for the RCT, the methodological quality was fair to poor. All studies were designed on an intention to treat basis, one also investigated BTX as a diagnostic tool to differentiate pectoralis minor syndrome from costoclavicular compression. Reduction of symptoms was reported in 46-63% of primary procedures; no significant difference was found in the RCT. The effect of repeated procedures could not be determined. Degree of symptom reduction was reported by up to 30-42% on the Short-form McGill Pain scale and up to 40 mm on a visual analog scale. Complication rates varied among studies, no major complications were reported. Symptom relief ranged from 1 to 6 months.

CONCLUSIONS

Based on limited quality evidence, BTX may provide short-lasting symptom relief in some neurogenic TOS patients but remains overall undecided. The role of BTX for treatment of vascular TOS and as a diagnostic tool in TOS is currently unexploited.

Non-Canonical Amino Acids in Analyses of Protease Structure and Function

All known organisms encode 20 canonical amino acids by base triplets in the genetic code. The cellular translational machinery produces proteins consisting mainly of these amino acids. Several hundred natural amino acids serve important functions in metabolism, as scaffold molecules, and in signal transduction. New side chains are generated mainly by post-translational modifications, while others have altered backbones, such as the β- or γ-amino acids, or they undergo stereochemical inversion, e.g., in the case of D-amino acids. In addition, the number of non-canonical amino acids has further increased by chemical syntheses. Since many of these non-canonical amino acids confer resistance to proteolytic degradation, they are potential protease inhibitors and tools for specificity profiling studies in substrate optimization and enzyme inhibition. Other applications include in vitro and in vivo studies of enzyme kinetics, molecular interactions and bioimaging, to name a few. Amino acids with bio-orthogonal labels are particularly attractive, enabling various cross-link and click reactions for structure-functional studies. Here, we cover the latest developments in protease research with non-canonical amino acids, which opens up a great potential, e.g., for novel prodrugs activated by proteases or for other pharmaceutical compounds, some of which have already reached the clinical trial stage.

The Effect of Botulinum Toxin Type A Injection in the Rectus Femoris in Stroke Patients Walking With a Stiff Knee Gait: A Randomized Controlled Trial

BACKGROUND

Over activity of the rectus femoris is often cited as a main cause for stiff knee gait (SKG). Botulinum toxin (BoNT) can be used to reduce this over activity. Inconsistent results for the effect of BoNT injections were found in literature which can possibly be explained by the study design as these were uncontrolled or non-randomized studies.

OBJECTIVE

To conduct a randomized controlled trial (RCT) to investigate the effect of botulinum toxin type A (BoNT-A) injections in the rectus femoris on gait kinematics and functional outcome in adult stroke patients.

METHODS

Twenty-six participants were included in this triple-blind cross-over RCT. The intervention consisted of an injection with BoNT-A. Placebo is an injection with saline. Besides knee and hip kinematics, functional outcomes were measured.

RESULTS

Comparison of the effect of BoNT-A injection to placebo injection showed a significant increase in peak knee flexion and knee range of motion of 6.7° and 4.8° respectively. There was no difference in hip kinematics. In functional outcomes, only the 6 Minute Walking Test showed a significant increase of 18.3 m.

CONCLUSIONS

BoNT-A injections in the rectus femoris is a valuable treatment option for stroke patients walking with a SKG to improve knee kinematics. To study the effect on functional outcome more research is necessary with different functional outcome measures that can capture the effect in kinematics. It is important to use kinematic measurements to demonstrate effects in quality of movement that are not captured by commonly used functional outcome measurements post stroke.Clinical Trial Registration: https://trialsearch.who.int/Trial2.aspx?TrialID=NTR2169.

Rivastigmine ameliorates botulinum-induced hippocampal damage and spatial memory impairment in male rats

Botulinum toxin (Botox) is widely used in beauty industry and its long-term consequences can be a matter of concern. The hippocampal cholinergic system plays a significant role in memory and learning that could be affected by Botulinum toxin. However, to date, the effect of Botox on memory system has been controversial. This survey aimed to examine the effects of Botox on spatial memory, and biochemical and histological parameters of the hippocampus in male rats by using Rivastigmine (R) as a cholinesterase inhibitor that is more selective for the central nervous system (CNS). Thirty-five male Wistar rats (200-250 g) were distributed into seven groups: Sham, Botox A (3, 6, and 15 IU intramascularly) and Botox A (3, 6, and 15 IU) plus Rivastigmine (1 mg/kg intraperitoneally). Spatial memory was assessed in the Morris Water Maze (MWM) 4 weeks later. Moreover, the hippocampal tissue was removed for histopathological and biochemical analyses. Botox significantly impaired memory performance in MWM by increasing escape latency and swim distance and decreasing the time spent in the target zone. Furthermore, in the Botox groups, the level of acetylcholine decreased, while the level of the acetylcholinesterase enzyme increased significantly in the hippocampus. Also, local lesions were observed in the form of degeneration and loss of pyramidal neurons, as well as a decrease in the volume and shrinkage of the cell body and an increase in microglia in the damaged area. Rivastigmine administration alleviated biochemical and histological parameters and partially ameliorated Botox-induced impairments. In summary, rivastigmine could be a suitable protective approach for side effects of Botox in the hippocampus.

Use of botulinum toxin in aesthetic medicine and gynaecology: current approaches, controversies, and future directions

This review looks at the use of botulinum toxin in the gynaecological field with the aim of determining what needs to be further investigated to achieve a standardized application. Numerous studies have been conducted to explore how botulinum toxins (BoNT) can be applied, and it is becoming popular for treating various disorders such as chronic pelvic pain, vestibulodynia, and vaginism. However, the exact dosage and ideal location for injections still need to be clarified. The objective of this study is to point out which aspects need to be more carefully studied to ensure a consistent use of BoNT in gynaecology.

A technology evaluation of the atypical use of a CPP-containing peptide in the formulation and performance of a clinical botulinum toxin product

INTRODUCTION

Cell-penetrating peptides (CPPs), are small peptides that facilitate cytosolic access and, thus, transport of therapeutic macromolecules to intracellular sites when conjugated to cargo proteins. As with all new delivery platforms, clinical development of CPP-containing therapeutics has faced considerable challenges.

AREAS COVERED

RTP004 is a novel, 35-amino acid, bi-CPP-containing excipient that binds noncovalently with its cargo (botulinum toxin type A) rather than conjugated as a fusion protein. An RTP004-containing neurotoxin formulation, daxibotulinumtoxinA-lanm for injection (DAXI), has recently been approved by the FDA. The formulation and pharmacological characteristics of RTP004 and the efficacy and safety of the RTP004-neurotoxin formulation are discussed.

EXPERT OPINION

RTP004 is a highly positively charged lysine- and arginine-rich structure that provides formulation stability, preventing self-aggregation of the cargo protein and adsorption to container surfaces. The presence of RTP004 in the formulation also appears to increase presynaptic binding of the neurotoxin, reduces post-injection diffusion, and thus facilitates an increase in the cleavage of the intracellular substrate for the botulinum toxin, likely through enhanced cellular uptake. The RTP004-neurotoxin formulation is the first CPP-containing product approved for clinical use. The potential for RTP004 to facilitate other therapeutic cargo molecules requires further research.

Dermatological Management of Aged Skin

The subject of the work concerns the dermatological management of patients mainly with aged skin. The purpose of the work was to present the basic techniques and preparations which are performed by dermatologists in the treatment of aged skin. There are dermatological treatments related to the treatment of skin diseases and cosmetic treatments which are mainly related to skin care. In this work, the method of literature research was applied. On the basis of books and journal articles on dermatological and cosmetic procedures for aged skin, an analysis of treatment types was made. Then, the results of this analysis were presented in the paper under discussion. The paper presents information on the skin and its properties. The structure and functions of the skin, aging processes and characteristics of aged skin were discussed. Then, the possibilities of reducing the visible signs of skin aging through the use of invasive and non-invasive dermatological and cosmetological treatments were given, and the most important components of preparations used supportively in combating skin aging processes were discussed.

Toxin-linked mobile genetic elements in major enteric bacterial pathogens

One of the fascinating outcomes of human microbiome studies adopting multi-omics technology is its ability to decipher millions of microbial encoded functions in the most complex and crowded microbial ecosystem, including the human gastrointestinal (GI) tract without cultivating the microbes. It is well established that several functions that modulate the human metabolism, nutrient assimilation, immunity, infections, disease severity and therapeutic efficacy of drugs are mostly of microbial origins. In addition, these microbial functions are dynamic and can disseminate between microbial taxa residing in the same ecosystem or other microbial ecosystems through horizontal gene transfer. For clinicians and researchers alike, understanding the toxins, virulence factors and drug resistance traits encoded by the microbes associated with the human body is of utmost importance. Nevertheless, when such traits are genetically linked with mobile genetic elements (MGEs) that make them transmissible, it creates an additional burden to public health. This review mainly focuses on the functions of gut commensals and the dynamics and crosstalk between commensal and pathogenic bacteria in the gut. Also, the review summarises the plethora of MGEs linked with virulence genes present in the genomes of various enteric bacterial pathogens, which are transmissible among other pathogens and commensals.

Structural basis of botulinum neurotoxin serotype A1 binding to human SV2A or SV2C receptors

Botulinum neurotoxin A1 (BoNT/A1) is the most potent natural poison in human. BoNT/A1 recognize the luminal domain of SV2A (LD-SV2A) and its glycosylation at position N573 (N573g) or the luminal domain of SV2C (LD-SV2C) and its glycosylation at position N559 (N559g) to bind neural membrane. Our computational data suggest that the N-glycan at position 480 (N480g) in the luminal domain of SV2C (LD-SV2C) indirectly enhanced the contacts of the neurotoxin surface with the second N-glycan at position 559 (N559g) by acting as a shield to prevent N559g to interact with residues of LD-SV2C. The absence of an N-glycan homologous to N480g in LD-SV2A leads to a decrease of the binding of N573g to the surface of BoNT/A1. Concerning the intermolecular interactions between BoNT/A and the protein part of LD-SV2A or LD-SV2C, we showed that the high affinity of the neurotoxin for binding LD-SV2C are mediated by a better compaction of its F557-F562 part provided by a π-π network mediated by residues F547, F552, F557 and F562 coupled with the presence of two aromatic residues at position 563 and 564 that optimize the binding of BoNT/A1 via cation-pi and CH-pi interaction. Finally, in addition to the well-known ganglioside binding site which accommodates a ganglioside on the surface of BoNT/A1, we identified a structure we coined the ganglioside binding loop defined by the sequence 1253-HQFNNIAK-1260 that is conserved across all subtypes of BoNT/A and is predicted to has a high affinity to interact with gangliosides. These data solved the puzzle generated by mutational studies that could be only partially understood with crystallographic data that lack both a biologically relevant membrane environment and a full glycosylation of SV2.

In silico prediction of molecular mechanisms of toxicity mediated by the leptospiral PF07598 gene family-encoded virulence-modifying proteins

Mechanisms of leptospirosis pathogenesis remain unclear despite the identification of a number of potential leptospiral virulence factors. We recently demonstrated potential mechanisms by which the virulence-modifying (VM) proteins-defined as containing a Domain of Unknown function (DUF1561), encoded by the PF07598 gene family-found only in group 1 pathogenic Leptospira-might mediate the clinical pathogenesis of leptospirosis. VM proteins belongs to classical AB toxin paradigm though have a unique AB domain architecture, unlike other AB toxins such as diphtheria toxin, pertussis toxin, shiga toxin, or ricin toxin which are typically encoded by two or more genes and self-assembled into a multi-domain holotoxin. Leptospiral VM proteins are secreted R-type lectin domain-containing exotoxins with discrete N-terminal ricin B-like domains involved in host cell surface binding, and a C-terminal DNase/toxin domain. Here we use the artificial intelligence-based AlphaFold algorithm and other computational tools to predict and elaborate on details of the VM protein structure-function relationship. Comparative AlphaFold and CD-spectroscopy defined the consistent secondary structure (Helix and ß-sheet) content, and the stability of the functional domains were further supported by molecular dynamics simulation. VM proteins comprises distinctive lectic family (QxW)₃ motifs, the Mycoplasma CARDS toxin (D3 domain, aromatic patches), C-terminal similarity with mammalian DNase I. In-silico study proposed that Gln412, Gln523, His533, Thr59 are the high binding energy or ligand binding residues plausibly anticipates in the functional activities. Divalent cation (Mg⁺²-Gln412) and phosphate ion (PO₄]^-3-Arg615) interaction further supports the functional activities driven by C-terminal domain. Computation-driven structure-function studies of VM proteins will guide experimentation towards mechanistic understandings of leptospirosis pathogenesis, which underlie development of new therapeutic and preventive measures for this devastating disease.

Duane Retraction Syndrome: The Role of Botulinum Toxin A Injection in Adults and Its Impact on Quality of Life in an Indian Population

PURPOSE

To evaluate the role of botulinum toxin A in the treatment of adults with Duane retraction syndrome and its impact on quality of life.

METHODS

A total of 25 adults with unilateral Duane retraction syndrome were selected for this interventional case series. Botulinum toxin was injected in the appropriate horizontal recti. The parameters assessed were ocular deviation (▵), overshoots, and abnormal head posture. Patients were followed up at 1 day, 10 days, and 3 months after the injection. The outcome was categorized on the basis of deviation/abnormal head posture/overshoots as: (1) significant improvement (< 8 prism diopters [PD]/< 5 degrees/≤ grade 1); (2) partial improvement (8 to 20 PD/5 to 15 degrees/≤ grade 2); and (3) no improvement (> 20 PD/> 15 degrees/≥ grade 3). Patients with partial/significant improvement were considered to have a favorable outcome. The impact on quality of life was assessed using the Adult Strabismus-20 Questionnaire scores 10 days after injection.

RESULTS

There was a significant reduction in ocular deviation in esotropic and exotropic Duane retraction syndrome at 10 days (P = .001) and 3 months (P = .04) after botulinum toxin injection. The abnormal head posture improved from 11.58 ± 7.43 to 7.86 ± 6.25 degrees at 10 days. Botulinum toxin had a positive impact on the Adult Strabismus-20 Questionnaire scores, which significantly improved (P < .05) at 10 days. A favorable outcome was noted in 21 patients at 10 days but only 4 patients at 3 months. Three patients developed ptosis and 1 patient with orthotropic Duane retraction syndrome developed transient exotropia.

CONCLUSIONS

In adults with Duane retraction syndrome, botulinum toxin can have a useful diagnostic role by providing insight to patients and setting realistic expectations. It can identify patients likely to benefit from further treatment and also has a positive impact on quality of life. [J Pediatr Ophthalmol Strabismus. 2023;60(1):46-51.].

Drug Therapeutics Delivery to the Salivary Glands: Intraglandular and Intraductal Injections

Salivary gland hypofunction and xerostomia following pathological conditions like Sjogren's syndrome or head and neck radiotherapy usually lead to tremendous impairment of oral health, speech, and swallowing. The use of systemic drugs to alleviate the symptoms of these conditions has been associated with various adverse effects. Techniques of local drug delivery to the salivary gland have grown enormously to address this problem properly. The techniques include intraglandular and intraductal injections. In this chapter, we will provide a review of the literature for both techniques while incorporating our lab experience in using them.

The Development of Psychiatric Illness and Chemoprophylaxis of Botulinum Toxin in Migraine: A Narrative Review

A migraine is not just a headache. It is an extremely prevalent neurological condition marked by periodic episodes of unilateral headache, with more than 10 million cases yearly. Migraine often begins at the age of puberty. It substantially impacts the brain and, consequently, psychiatric behavior linked with frequent migraine attacks that may be moderate to severe in intensity. A crucial aspect of migraine variability is comorbidity with other neurological diseases, vascular diseases, and mental illnesses. Psychiatric disorders related to migraine include anxiety disorders, panic disorder, bipolar disorder, depression, etc. It is also estimated that people suffering from migraine are about five times more likely to develop depression than others without migraine. The stimulus for migraine is stress, lack of sleep, skipped meal or fasting, visual stimulation due to high intensity of light, auditory stimulus due to noise, and olfactory stimulus due to a pungent smell. A majority of patients suffer from migraine attacks triggered by noise, some due to visual stimulation, and a few due to perfumes or other odors that trigger their migraine. Diagnosis of this is primarily dependent on history taking and clinical evaluation. Migraine can be classified depending on whether an aura is present or absent. It can further be divided based on the frequency of headaches into episodic migraine or chronic migraine, which may be determined by the duration of the headache. The development of migraine is influenced by both genetics and the environment. It has a detrimental effect on children's quality of life. A comprehensive analysis of psychiatric illnesses in migraine contributes to early diagnosis and proper treatment of the disease. Also, having a healthy lifestyle (including exercise, a balanced diet, and enough sleep) seems to prevent and improve the condition. Headache in migraine is resistant to medical treatment but responds well to botulinum toxin. This review primarily focuses on the psychiatric issues like depression and anxiety that often accompany migraine. The article also highlights the effects of botulinum toxin on migraine.

Botulinum Neurotoxin Therapy in the Clinical Management of Laryngeal Dystonia

Laryngeal dystonia (LD), or spasmodic dysphonia (SD), is a chronic, task-specific, focal movement disorder affecting the larynx. It interferes primarily with the essential functions of phonation and speech. LD affects patients' ability to communicate effectively and significantly diminishes their quality of life. Botulinum neurotoxin was first used as a therapeutic agent in the treatment of LD four decades ago and remains the standard of care for the treatment of LD. This article provides an overview of the clinical application of botulinum neurotoxin in the management of LD, focusing on the classification for this disorder, its pathophysiology, clinical assessment and diagnosis, the role of laryngeal electromyography and a summary of therapeutic injection techniques, including a comprehensive description of various procedural approaches, recommendations for injection sites and dosage considerations.

Effects of Botulinum Toxin Injection on Reducing Myogenic Artifacts during Video-EEG Monitoring: A Longitudinal Study

Medically refractory seizures affect one-third of patients with epilepsy (PwE), for whom epilepsy surgery is considered. Video electroencephalography (vEEG) monitoring is a fundamental tool for pre-operative seizure localization. Facial and cranial myogenic artifacts can obscure vEEG findings, thus interfering with seizure localization. Studies have shown the beneficial effects of botulinum toxin type A (BTX-A) injection into cranial muscles for reducing myogenic artifacts. This longitudinal study aimed to assess the effects of BTX-A injection on these artifacts. Twenty-two patients with medically refractory hypermotor seizures with daily seizure frequency and undetermined epilepsy localization were included in this study and underwent Dysport® injection (200 units) into the frontotemporal region. vEEG recordings were performed at baseline (one week before the injection), and at three days and six days post-injection. Before and after the injection, the amplitudes of myogenic artifacts were compared during various states (ictal, blinking, chewing, bruxism, head lateralization, scowling, talking, and yawning). BTX-A injection significantly reduced the amplitudes of EEG myogenic artifacts, except during blinking (day three) and talking (days three and six). On day six, significant reduction in EEG myogenic artifacts were noted during blinking, chewing, and bruxism for the greatest number of patients (95.5%, 90.9%, 81.8%), while significant reductions in EEG myogenic artifacts during talking, head lateralization, and ictal phase were associated with the least number of patients (22.7%, 36.3%, and 40.9%). Therefore, BTX-A injection could be a convenient method for filtering myogenic contamination, improving EEG interpretation, and facilitating seizure localization in patients with medically refractory seizures.

Efficacy and safety of botulinum toxin-A in writer’s cramp: a systematic review, meta-analysis, and meta-regression

Background

Botulinum toxin-A (BoNT) reduce over-firing of dystonic muscles, spasmodic contractions by enhancing function. We conducted a systematic review and random-effects meta-regression to investigate the efficacy and safety of BoNT in writer’s cramp (WC). Published electronic articles from inception till January 2022 were screened from four databases (Medline, Science Direct, Scopus, ProQuest). Effect sizes in the form of standardized mean differences were calculated for estimation of efficacy.

Results

Nineteen studies [six randomized control trials (RCTs) and 13 observational studies] involved 587 (514 experimental; 73 Controls) participants with mean age of 43.46 ± 8.84 years with mean duration of WC of 8.31 ± 5.35 years. Injection did not result in significant improvement in writing speed [standard mean difference (95% CI) 0.06 (− 0.35, 0.46)]. There was no significant difference in writing speed as compared to controls [standard mean difference (95% CI) − 0.51 (− 2.55, 1.52)]. The meta-analysis of observational studies showed a significant difference in the mean WC rating score [standard mean difference (95% CI) 0.54 (0.20, 0.88)]. Pooled analysis (observational studies and RCTs) demonstrated a significant difference in the mean Writer’s cramp rating score (WCRS) after BoNT [standard mean difference (95% CI) 0.75 (0.06, 1.44)]. No major safety concerns were reported in the included studies.

Conclusions

According to the meta-analysis of observational studies, BoNT injections are effective in WC for improving WCRS without major safety concerns. However, according to the meta-analysis of RCTs, there was no significant effect in efficacy with BoNT.

Overactive bladder: not just a normal part of getting older

Overactive bladder (OAB) is a common yet under-reported condition affecting both men and women. Prevalence rises with age, but OAB can affect people of any age. It is associated with increased physical and mental health problems and may lead to social isolation and escalating care needs. It is a clinical diagnosis with symptoms of urgency, with or without urge incontinence and usually with urinary frequency and nocturia. Management includes conservative, medical and surgical treatments, which can significantly improve quality of life. This review aims to raise awareness of this under-reported condition and to empower health professionals to open discussions on bladder health with all those in their care.

Effectiveness of Botulinum Neurotoxin in Treatment of Scoliosis among Children and Adolescents: A Systematic Review and Meta-Analysis

Scoliosis refers to a three-dimensional deviation in the axis of the spine. Muscle imbalance is believed to play a role in scoliosis. Botulinum neurotoxin (BoNT) can reduce muscle overactivity and may have the potential to ameliorate spinal scoliosis. This study investigated the effectiveness of intramuscular BoNT injection in vertebral curve correction and reviewed the possible influencing factors. PubMed, Medline, Cochrane Central Register of Controlled Trials, Web of Science, Airiti Library, and Index of the Taiwan Periodical Literature System databases were searched from inception until 7 September 2022 for eligible studies. The main outcome was the change in Cobb angle after BoNT application. Subgroup analysis was conducted according to differences in study designs, etiology of scoliosis, and methods used for target muscle selection. We enrolled three studies including 31 participants aged between 2 and 18 years. The meta-analysis revealed no significant reduction in the Cobb angle after BoNT injection (standardized mean difference, −0.783, 95% CI, −2.142 to 0.576). Study designs (p = 0.011) and methods used for target muscle selection (p = 0.017) but not etiology of scoliosis (p = 0.997) reached statistical significance between subgroups. In conclusion, the current meta-analysis does not support the application of BoNT in children and adolescents with scoliosis. However, a decisive conclusion could not be made due to high between-study heterogeneity and small sample size. More randomized controlled trials with appropriate target muscle selection and standard outcome measurement should be conducted to examine the efficacy of botulinum neurotoxin in treating scoliosis. INPLASY ID: INPLASY202290031.