Botulinum toxin type A versus botulinum toxin type B for cervical dystonia

BACKGROUND: This is an update of a Cochrane review first published in 2003. Cervical dystonia is the most common form of focal dystonia and is a disabling disorder characterised by painful involuntary head posturing. There are two available formulations of botulinum toxin, with botulinum toxin type A (BtA) usually considered the first line therapy for this condition. Botulinum toxin type B (BtB) is an alternative option, with no compelling theoretical reason why it might not be as- or even more effective - than BtA. OBJECTIVES: To compare the efficacy, safety and tolerability of botulinum toxin type A (BtA) versus botulinum toxin type B (BtB) in people with cervical dystonia. SEARCH METHODS: To identify studies for this review we searched the Cochrane Movement Disorders Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, reference lists of articles and conference proceedings. All elements of the search, with no language restrictions, were last run in October 2016. SELECTION CRITERIA: Double-blind, parallel, randomised, placebo-controlled trials (RCTs) comparing BtA versus BtB in adults with cervical dystonia. DATA COLLECTION AND ANALYSIS: Two independent authors assessed records, selected included studies, extracted data using a paper pro forma, and evaluated the risk of bias. We resolved disagreements by consensus or by consulting a third author. We performed meta-analyses using the random-effects model, for the comparison BtA versus BtB to estimate pooled effects and corresponding 95% confidence intervals (95% CI). No prespecified subgroup analyses were carried out. The primary efficacy outcome was improvement on any validated symptomatic rating scale, and the primary safety outcome was the proportion of participants with adverse events. MAIN RESULTS: We included three RCTs, all new to this update, of very low to low methodological quality, with a total of 270 participants.Two studies exclusively enrolled participants with a known positive response to BtA treatment. This raises concerns of population enrichment, with a higher probability of benefit from BtA treatment. None of the trials were free of for-profit bias, nor did they provide information regarding registered study protocols. All trials evaluated the effect of a single Bt treatment session, and not repeated treatment sessions, using doses from 100 U to 250 U of BtA (all onabotulinumtoxinA, or Botox, formulations) and 5000 U to 10,000 U of BtB (rimabotulinumtoxinB, or Myobloc/Neurobloc).We found no difference between the two types of botulinum toxin in terms of overall efficacy, with a mean difference of -1.44 (95% CI -3.58 to 0.70) points lower on the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) for BtB-treated participants, measured at two to four weeks after injection. The proportion of participants with adverse events was also not different between BtA and BtB (BtB versus BtA risk ratio (RR) 1.40; 95% CI 1.00 to 1.96). However, when compared to BtA, treatment with BtB was associated with an increased risk of one adverse events of special interest, namely treatment-related sore throat/dry mouth (BtB versus BtA RR of 4.39; 95% CI 2.43 to 7.91). Treatment-related dysphagia (swallowing difficulties) was not different between BtA and BtB (RR 2.89; 95% CI 0.80 to 10.41). The two types of botulinum toxin were otherwise clinically non-distinguishable in all the remaining outcomes. AUTHORS' CONCLUSIONS: The previous version of this review did not include any trials, since these were still ongoing at the time. Therefore, with this update we are able to change the conclusions of this review. There is low quality evidence that a single treatment session of BtA (specifically onabotulinumtoxinA) and a single treatment session of BtB (rimabotulinumtoxinB) are equally effective and safe in the treatment of adults with certain types of cervical dystonia. Treatment with BtB appears to present an increased risk of sore throat/dry mouth, compared to BtA. Overall, there is no clinical evidence from these single-treatment trials to support or contest the preferential use of one form of botulinum toxin over the other

Botulinum toxin type B for cervical dystonia

BACKGROUND: This is an update of a Cochrane review first published in 2004, and previously updated in 2009 (no change in conclusions). Cervical dystonia is a frequent and disabling disorder characterised by painful involuntary head posturing. Botulinum toxin type A (BtA) is usually considered the first line therapy for this condition, although botulinum toxin type B (BtB) is an alternative option. OBJECTIVES: To compare the efficacy, safety and tolerability of botulinum toxin type B (BtB) versus placebo in people with cervical dystonia. SEARCH METHODS: We identified studies for inclusion in the review using the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, reference lists of articles and conference proceedings, last run in October 2015. We ran the search from 1977 to 2015. The search was unrestricted by language. SELECTION CRITERIA: Double-blind, parallel, randomised, placebo-controlled trials (RCTs) of BtB versus placebo in adults with cervical dystonia. DATA COLLECTION AND ANALYSIS: Two independent authors assessed records, selected included studies, extracted data using a paper pro forma and evaluated the risk of bias. We resolved disagreements by consensus or by consulting a third author. We performed one meta-analysis for the comparison BtB versus placebo. We used random-effects models when there was heterogeneity and fixed-effect models when there was no heterogeneity. In addition, we performed pre-specified subgroup analyses according to BtB doses and BtA previous clinical responsiveness. The primary efficacy outcome was overall improvement on any validated symptomatic rating scale. The primary safety outcome was the number of participants with any adverse event. MAIN RESULTS: We included four RCTs of moderate overall methodological quality, including 441 participants with cervical dystonia. Three studies excluded participants known to have poorer response to Bt treatment, therefore including an enriched population with a higher probability of benefiting from Bt treatment. None of the trials were independently funded. All RCTs evaluated the effect of a single Bt treatment session using doses between 2500 U and 10,000 U. BtB was associated with an improvement of 14.7% (95% CI 9.8% to 19.5) in the patients' baseline clinical status as assessed by investigators, with reduction of 6.8 points in the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS-total score) at week 4 after injection (95% CI 4.54 to 9.01). Mean difference (MD) in TWSTRS-pain score at week 4 was 2.20 (95% CI 1.25 to 3.15). Overall, both participants and clinicians reported an improvement of subjective clinical status. There were no differences between groups in the withdrawals rate due to adverse events or in the proportion of participants with adverse events. However, BtB-treated patients had a 7.65 (95% CI 2.75 to 21.32) and a 6.78 (95% CI 2.42 to 19.05) increased risk of treatment-related dry mouth and dysphagia, respectively. Statistical heterogeneity between studies was low to moderate for most outcomes. All tested dosages were efficacious against placebo without clear-cut evidence of a dose-response gradient. However, duration of effect (time until return to baseline TWSTRS-total score) and risk of dry mouth and dysphagia were greater in the subgroup of participants treated with higher BtB doses. Subgroup analysis showed a higher improvement with BtB among BtA-non-responsive participants, although there were no differences in the effect size between the BtA-responsive and non-responsive subgroups. AUTHORS' CONCLUSIONS: A single BtB-treatment session is associated with a significant and clinically relevant reduction of cervical dystonia impairment including severity, disability and pain, and is well tolerated, when compared with placebo. However, BtB-treated patients are at an increased risk of dry mouth and dysphagia. There are no data from RCTs evaluating the effectiveness and safety of repeated BtB injection cycles. There are no RCT data to allow us to draw definitive conclusions on the optimal treatment intervals and doses, usefulness of guidance techniques for injection, and impact on quality of life

Fitness of evolving bacterial populations is contingent on deep and shallow history but only shallow history creates predictable patterns

Long-term evolution experiments have tested the importance of genetic and environmental factors in influencing evolutionary outcomes. Differences in phylogenetic history, recent adaptation to distinct environments and chance events, all influence the fitness of a population. However, the interplay of these factors on a population's evolutionary potential remains relatively unexplored. We tracked the outcome of 2000 generations of evolution of four natural isolates of Escherichia coli bacteria that were engineered to also create differences in shallow history by adding previously identified mutations selected in a separate long-term experiment. Replicate populations started from each progenitor evolved in four environments. We found that deep and shallow phylogenetic histories both contributed significantly to differences in evolved fitness, though by different amounts in different selection environments. With one exception, chance effects were not significant. Whereas the effect of deep history did not follow any detectable pattern, effects of shallow history followed a pattern of diminishing returns whereby fitter ancestors had smaller fitness increases. These results are consistent with adaptive evolution being contingent on the interaction of several evolutionary forces but demonstrate that the nature of these interactions is not fixed and may not be predictable even when the role of chance is small.fals

Validity and reliability of a modified english version of the physical activity questionnaire for adolescents

BACKGROUND: Adaptation of physical activity self-report questionnaires is sometimes required to reflect the activity behaviours of diverse populations. The processes used to modify self-report questionnaires though are typically underreported. This two-phased study used a formative approach to investigate the validity and reliability of the Physical Activity Questionnaire for Adolescents (PAQ-A) in English youth. Phase one examined test content and response process validity and subsequently informed a modified version of the PAQ-A. Phase two assessed the validity and reliability of the modified PAQ-A. METHODS: In phase one, focus groups (n = 5) were conducted with adolescents (n = 20) to investigate test content and response processes of the original PAQ-A. Based on evidence gathered in phase one, a modified version of the questionnaire was administered to participants (n = 169, 14.5 ± 1.7 years) in phase two. Internal consistency and test-retest reliability were assessed using Cronbach’s alpha and intra-class correlations, respectively. Spearman correlations were used to assess associations between modified PAQ-A scores and accelerometer-derived physical activity, self-reported fitness and physical activity self-efficacy. RESULTS: Phase one revealed that the original PAQ-A was unrepresentative for English youth and that item comprehension varied. Contextual and population/cultural-specific modifications were made to the PAQ-A for use in the subsequent phase. In phase two, modified PAQ-A scores had acceptable internal consistency (α = 0.72) and test-retest reliability (ICC = 0.78). Modified PAQ-A scores were significantly associated with objectively assessed moderate-to-vigorous physical activity (r = 0.39), total physical activity (r = 0.42), self-reported fitness (r = 0.35), and physical activity self-efficacy (r = 0.32) (p ≤ 0.01). CONCLUSIONS: The modified PAQ-A had acceptable internal consistency and test-retest reliability. Modified PAQ-A scores displayed weak-to-moderate correlations with objectively measured physical activity, self-reported fitness, and self-efficacy providing evidence of satisfactory criterion and construct validity, respectively. Further testing with more diverse English samples is recommended to provide a more complete assessment of the tool. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13690-016-0115-2) contains supplementary material, which is available to authorized users

Botulinum toxin type A therapy for hemifacial spasm

BACKGROUND: This is an update of a Cochrane Review, first published in 2005. Hemifacial spasm (HFS) is characterised by unilateral, involuntary contractions of the muscles innervated by the facial nerve. It is a chronic disorder, and spontaneous recovery is very rare. The two treatments routinely available are microvascular decompression and intramuscular injections with botulinum toxin type A (BtA). OBJECTIVES: To compare the efficacy, safety, and tolerability of BtA versus placebo in people with HFS. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, reference lists of articles, and conference proceedings in July 2020. We ran the electronic database search, with no language restrictions, in July 2020. SELECTION CRITERIA: Double-blind, parallel, randomised, placebo-controlled trials (RCTs) of BtA versus placebo in adults with HFS. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed records. We planned to select included studies, extract data using a paper pro forma, and evaluate the risk of bias. We resolved disagreements by consensus, or by consulting a third review author. We planned to perform meta-analyses. The primary efficacy outcome was HFS-specific improvement. The primary safety outcome was the proportion of participants with any adverse event. MAIN RESULTS: We found no parallel-group randomised controlled trials comparing BtA and placebo in HFS. AUTHORS' CONCLUSIONS: We did not find any randomised trials that evaluated the efficacy and safety of botulinum toxin type A in people with hemifacial spasm, so we are unable to draw any conclusions. Observational data show a strong association between BtA treatment and symptom improvement, and a favourable safety profile. While it is unlikely that future placebo-controlled RCTs will evaluate absolute efficacy and safety, they should address relevant questions for both people with HFS (such as long-term effects, quality of life, and other patient-reported outcomes), and clinicians (such as relative effectiveness of different BtA formulations and schemes of treatment) to better guide clinical practice.)

The implications of a Silurian and other thylacocephalan crustaceans for the functional morphology and systematic affinities of the group

Background: Thylacocephala is a group of enigmatic extinct arthropods. Here we provide a full description of the oldest unequivocal thylacocephalan, a new genus and species Thylacares brandonensis, which is present in the Silurian Waukesha fauna from Wisconsin, USA. We also present details of younger, Jurassic specimens, from the Solnhofen lithographic limestones, which are crucial to our interpretation of the systematic position of Thylacocephala. In the past, Thylacocephala has been interpreted as a crustacean ingroup and as closely related to various groups such as cirripeds, decapods or remipeds. Results: The Waukesha thylacocephalan, Thylacares brandonensis n. gen. n. sp., bears compound eyes and raptorial appendages that are relatively small compared to those of other representatives of the group. As in other thylacocephalans the large bivalved shield encloses much of the entire body. The shield lacks a marked optical notch. The eyes, which project just beyond the shield margin, appear to be stalked. Head appendages, which may represent antennulae, antennae and mandibles, appear to be present. The trunk is comprised of up to 22 segments. New details observed on thylacocephalans from the Jurassic Solnhofen lithographic limestones include antennulae and antennae of Mayrocaris bucculata, and endites on the raptorial appendages and an elongate last trunk appendage in Clausocaris lithographica. Preserved features of the internal morphology in C. lithographica include the muscles of the raptorial appendage and trunk. Conclusions: Our results indicate that some `typical' thylacocephalan characters are unique to the group; these autapomorphies contribute to the difficulty of determining thylacocephalan affinities. While the new features reported here are consistent with a eucrustacean affinity, most previous hypotheses for the position of Thylacocephala within Eucrustacea (as Stomatopoda, Thecostraca or Decapoda) are shown to be unlikely. A sister group relationship to Remipedia appears compatible with the observed features of Thylacocephala but more fossil evidence is required to test this assertion. The raptorial appendages of Thylacocephala most likely projected 45 degrees abaxially instead of directly forward as previously reconstructed. The overall morphology of thylacocephalans supports a predatory mode of life

Highly polymorphic microsatellite markers for the assessment of male reproductive skew and genetic variation in Critically Endangered crested macaques (Macaca nigra)

Genetic analyses based on non-invasively collected samples have become an important tool for evolutionary biology and conservation. Crested macaques (Macaca nigra), endemic to Sulawesi, Indonesia, are important for our understanding of primate evolution as Sulawesi macaques represent an exceptional example of primate adaptive radiation. Crested macaques are also Critically Endangered. However, to date we know very little about their genetics. The aim of our study was to find and validate microsatellite markers useful for evolutionary, conservation and other genetic studies on wild crested macaques. Using faecal samples of 176 wild macaques living in the Tangkoko Reserve, Sulawesi, we identified 12 polymorphic microsatellite loci through cross-species PCR amplification with later modification of some of these primers. We tested their suitability by investigating and exploring patterns of paternity, observed heterozygosity and evidence for inbreeding. We assigned paternity to 63 of 65 infants with high confidence. Among cases with solved paternity, we found no evidence of extra-group paternity and natal breeding. We found a relatively steep male reproductive skew B index of 0.330±0.267; mean±SD) and mean alpha paternity of 65% per year with large variation across groups and years (29-100%). Finally, we detected an excess in observed heterozygosity and no evidence of inbreeding across our three study groups, with an observed heterozygosity of 0.766±0.059 and expected heterozygosity of 0.708±0.059, and an inbreeding coefficient of -0.082±0.035. Our results indicate that the selected markers are useful for genetic studies on wild crested macaques, and possible also other Sulawesi and closely related macaques. They further suggest that the Tangkoko population of crested macaques is still genetically variable despite its small size, isolation and the species’ reproductive patterns. This gives us hope that other endangered primate species living in small, isolated populations may also retain a healthy gene pool, at least in the short term

Botulinum toxin type A therapy for blepharospasm

BACKGROUND: This is an update of a Cochrane Review first published in 2005. Blepharospasm is the second most common form of focal dystonia. It is a disabling disorder, characterised by chronic, intermittent or persistent, involuntary eyelid closure, due to spasmodic contractions of the orbicularis oculi muscles. Currently, botulinum toxin type A (BtA) is considered the first line of therapy for this condition. OBJECTIVES: To compare the efficacy, safety, and tolerability of BtA versus placebo in people with blepharospasm. SEARCH METHODS: We searched Cochrane Movement Disorders' Trials Register, CENTRAL, MEDLINE, Embase, reference lists of included articles, and conference proceedings. We ran all elements of the search, with no language restrictions, in July 2020. SELECTION CRITERIA: Double-blind, parallel, randomised, placebo-controlled trials (RCTs) of BtA versus placebo in adults with blepharospasm. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed records, selected included studies, extracted data using a paper pro forma, and evaluated the risk of bias. We resolved disagreements by consensus, or by consulting a third review author. We performed meta-analyses using a random-effects model, for the comparison of BtA versus placebo, to estimate pooled effects and corresponding 95% confidence intervals (95% CI). We did not carry out any prespecified subgroup analyses. The primary efficacy outcome was improvement on any validated symptomatic rating scale. The primary safety outcome was the proportion of participants with any adverse event. MAIN RESULTS: We included three RCTs, assessed at low to moderate overall risk of bias, which randomised 313 participants with blepharospasm. Two studies excluded participants with poorer prior responses to BtA treatment, therefore, they included an enriched population with a higher probability of benefiting from this therapy. All trials were industry-funded. All RCTs evaluated the effect of a single BtA treatment session. BtA resulted in a moderate to large improvement in blepharospasm-specific severity, with a reduction of 0.93 points on the Jankovic Rating Scale (JRS) severity subscale at four to six weeks after injection (95% confidence interval (CI) 0.61 to 1.25; I² = 9%) compared to placebo. BtA was also resulted in a moderate to large improvement in blepharospasm-specific disability and blepharospasm-specific involuntary movements at four to six weeks after injection (disability: 0.69 JRS disability subscale points, 95% CI 0.18 to 1.19; I² = 74%; blepharospasm-specific involuntary movements: standardised mean difference (SMD) 0.79, 0.31 to 1.27; I² = 58%) compared to placebo. BtA did not show a risk of adverse events (risk ratio (RR) 1.18, 95% CI 0.87 to 1.60; I² = 0%). However, BtA increased the risk of vision complaints and eyelid ptosis (vision complaints: RR 5.73, 95% CI 1.79 to 18.36; I² = 51%; eyelid ptosis: RR 4.02, 95% CI 1.61 to 10.00; I² = 39%). There was no distinction between BtA and placebo in the number of participants who dropped out of the trial. A single trial estimated the duration of effects to be 10.6 weeks (range 6.1 to 19.1). We found no evidence supporting the existence of a clear dose-response relationship with BtA. We found no data reporting the impact of BtA on health-related quality of life, or the development of secondary non-responsiveness. AUTHORS' CONCLUSIONS: We are moderately certain that a single BtA treatment resulted in a clinically relevant reduction of blepharospasm-specific severity and disability, and have low certainty that it is well tolerated, when compared with placebo. There is low-certainty evidence that people treated with BtA are not at an increased risk of developing adverse events, though BtA treatment likely increases the risk of visual complaints and eyelid ptosis. There are no data from RCTs evaluating the effectiveness and safety of repeated BtA injection cycles. There is no evidence from RCTs to allow us to draw definitive conclusions on the optimal treatment intervals and doses, or the impact on quality of life