Botulinum toxin blocks mast cells and prevents rosacea like inflammation

Background

Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.

注射用肉毒毒素制剂及其研发进展

肉毒毒素(Botulinum Toxin,BoNT)已成为现代医学最具多用途的治疗药物之一。通过将肉毒毒素注射到特定过度活动的肌肉中,可以阻断神经和肌肉之间的信号传导,引起肌肉的松弛性麻痹,从而达到治疗的功效。从业者应熟悉各类产品的特性,以实现安全有效地使用。除了已经上市的众多肉毒毒素产品外,目前还在开发其他新型制剂,这些产品将会进一步扩大肉毒毒素的适用范围,以及给患者提供更多的选择。     

逼尿肌尿道外括约肌协同失调的肉毒素A治疗

目的探讨肉毒素A(BTX-A)经尿道尿道外括约肌注射,治疗逼尿肌尿道外括约肌协同失调(DESD)的效果。方法对11例因患DESD致慢性尿潴留和尿失禁患者,行经尿道尿道外括约肌注射100UBTX-A治疗,对治疗前后的残余尿(PVR)、最大尿道压(MUP)、排尿期最大逼尿肌压(MPdet)和国际尿失禁咨询委员会尿失禁评分调查简表(ICI-Q-SF)评分进行比较。结果治疗后,MUP、MPdet和ICI-Q-SF显著降低,PVR显著减少。7~30天达最大疗效,单次注射疗效持续2~3个月,重复注射可持续更长时间。无严重不良反应发生。结论BTX-A尿道外括约肌注射治疗DESD,安全,微创,疗效确切;但需要重复注射维持疗效。     

Modification of Blood Vessel Diameter Following Perivascular Application of Botulinum Toxin-A

The purpose of this study was to demonstrate that perivascularly applied botulinum toxin-A (BTX) increases the diameter of treated blood vessels in a rat femoral vessel exposure model. Six adult Sprague–Dawley rats were used and bilateral femoral artery and vein exposures were performed. Five units of BTX were applied to the experimental side and an equal volume of sterile saline was applied to the control side. Digital images of the vessels were obtained at the following time points: pretreatment, immediately posttreatment, and postoperative days (POD) 1, 14, and 28. Vessel diameters were equivalent at baseline and immediately following application of BTX and saline. The BTX artery was significantly larger than the control artery on POD 1 and 14. The BTX treated artery was significantly larger than all other vessels on POD 14 (p < 0.05) as well as all prior time points (p < 0.01). Direct perivascular application of BTX increases the diameter of rat femoral vessels as early as POD 1. The affect is most robust on POD 14 where the artery was significantly larger than all other vessels at all time points. It is likely that the increased diameter of blood vessels results in an increased blood flow across the area of dilation. Such an increase in flow may serve to improve end-organ perfusion in microvascular procedures.     

Detection of proteinous toxins using the Bio-Threat Alert system, part 3: effects of heat pretreatment and interfering substances

We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively. The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations.     

A cyclic peptide–polymer probe for the detection of Clostridium botulinum neurotoxin serotype A

A Botulinum neurotoxin serotype A (BoNT/A) ELISA detection system was developed based upon an 11-mer cyclic peptide, termed C11-019, that was identified through peptide phage display technology. The assay employs a sandwich format using the C11-019 cyclic peptide attached to a PEMA (poly(ethylene maleic anhydride)) matrix as the capture phase and anti-BoNT/A polyclonal antibodies as the detection phase. Results reported demonstrate that the C11-019 peptide–polymer can specifically bind to BoNT/A with no cross-reactivity to other serotypes examined in assay buffers and a variety of body fluids and foodstuffs. When a highly sensitive chemiluminescent substrate was engaged, the detection of 1 pg/mL could be readily achieved within 3 h with a linear range of 0.1–1 ng/mL. These results demonstrate that an inexpensive peptide–polymer-based capture ELISA system can be used for rapid, sensitive and highly specific BoNT detection.     

Long-term follow-up by video of cervical dystonia treated with botulinum toxin

We have analysed video recordings of 21 patients with cervical dystonia treated with botulinum toxin. Fourteen patients have a record both of their response shortly after injections were commenced and between four years five months and six years seven months later. Our analysis shows that the long term outcome is often better than the initial response. We suggest that chronic treatment with botulinum toxin allows different muscles to those initially injected to be identified as contributors to the dystonia. Subsequent injection of these muscles leads to further improvement. It implies that cervical dystonia is a more widespread disorder of motor control, rather than simply limited to a few muscles.     

Injection of botulinum A toxin into the gastrocnemius muscle of patients with cerebral palsy: a 3-dimensional motion analysis study

Botulinum A toxin (BOTOX^®) was injected into the gastrocnemius muscle of 26 cerebral palsy subjects with equinus gait. All subjects were equinus walkers without fixed contracture of the triceps-surae muscle. Injections were performed at 3 month intervals, if needed, as determined by the treating clinician. There were 14 subjects with spastic hemiplegia, 11 subjects with spastic diplegia and 1 subject with spastic quadriplegia. In the case of those subjects with bilateral equinus gait the dose was divided and given into both the right and left gastrocnemius muscle. Gait analysis data was collected prior to the first injection and subsequently at 3 month intervals for 1 year. Kinematic and electromyographic data was obtained. This data was analyzed to provide objective information about the outcome of treatment. Four subjects moved away and were lost to follow-up. Seven subjects left the study to have surgery. The data collected revealed statistically significant improvements in dynamic ankle dorsiflexion in both stance and swing phases, stride length, and electromyography of the tibialis anterior. There were no complications. While the results of this study are promising, additional prospective studies are needed to determine the feasibility of preventing muscle contractures over a longer time period. Furthermore, there is a need for inclusion of other muscles in future research. Future research should also compare BOTOX^® treatment with alternative methods of dealing with muscle spasticity such as: casting, orthotic devices, physical therapy, selective dorsal rhizotomy, and surgical lengthening.