Effectiveness of Long-Term Physiotherapy in Parkinson's Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: Long-term physiotherapy is acknowledged to be crucial to manage motor symptoms for Parkinson's disease (PD) patients, but its effectiveness is not well understood. OBJECTIVE: This systematic review and meta-analysis aimed to assess the evidence regarding the effectiveness of long-term physiotherapy to improve motor symptoms and reduce antiparkinsonian medication dose in PD patients. METHODS: Pubmed, Cochrane, PEDro, and CINAHL were searched for randomized controlled trials before August 31, 2020 that investigated the effectiveness of physiotherapy for 6 months or longer on motor symptoms and levodopa-equivalent dose (LED) in PD patients with Hoehn and Yahr stage 1- 3. We performed random effects meta-analyses for long-term physiotherapy versus no/control intervention and estimated standard mean differences with 95% confidence intervals (CIs). Levels of evidence were rated by the Grading of Recommendation Assessment, Development and Evaluation approach. RESULTS: From 2,940 studies, 10 studies involving 663 PD patients were assessed. Long-term physiotherapy had favorable effects on motor symptoms in off medication state [- 0.65, 95% CI - 1.04 to - 0.26, p = 0.001] and LED [- 0.49, 95% CI - 0.89to - 0.09, p = 0.02]. Subgroup analyses demonstrated favorable effects on motor symptoms in off medication state by aerobic exercise [- 0.42, 95% CI - 0.64 to - 0.20, p < 0.001] and LED by multidisciplinary rehabilitation of primarily physiotherapy [- 1.00, 95% CI - 1.44 to - 0.56, p < 0.001]. Quality of evidence for aerobic exercise and multidisciplinary rehabilitation were low and very low. CONCLUSION: This review provided evidence that long-term physiotherapy has beneficial impact on motor symptoms and antiparkinsonian medication dose in PD patients and could motivate implementation of long-term physiotherapy.

Identification of A Novel Arsenic Resistance Transposon Nested in A Mercury Resistance Transposon of Bacillus sp. MB24.

A novel TnMERI1-like transposon designated as TnMARS1 was identified from mercury resistant Bacilli isolated from Minamata Bay sediment. Two adjacent ars operon-like gene clusters, ars1 and ars2, flanked by a pair of 78-bp inverted repeat sequences, which resulted in a 13.8-kbp transposon-like fragment, were found to be sandwiched between two transposable genes of the TnMERI1-like transposon of a mercury resistant bacterium, Bacillus sp. MB24. The presence of a single transcription start site in each cluster determined by 5'-RACE suggested that both are operons. Quantitative real time RT-PCR showed that the transcription of the arsR genes contained in each operon was induced by arsenite, while arsR2 responded to arsenite more sensitively and strikingly than arsR1 did. Further, arsenic resistance complementary experiments showed that the ars2 operon conferred arsenate and arsenite resistance to an arsB-knocked out Bacillus host, while the ars1 operon only raised arsenite resistance slightly. This transposon nested in TnMARS1 was designated as TnARS1. Multi-gene cluster blast against bacteria and Bacilli whole genome sequence databases suggested that TnMARS1 is the first case of a TnMERI1-like transposon combined with an arsenic resistance transposon. The findings of this study suggested that TnMERI1-like transposons could recruit other mobile elements into its genetic structure, and subsequently cause horizontal dissemination of both mercury and arsenic resistances among Bacilli in Minamata Bay.

Mercury resistance transposons in Bacilli strains from different geographical regions.

A total of 65 spore-forming mercury-resistant bacteria were isolated from natural environments worldwide in order to understand the acquisition of additional genes by and dissemination of mercury resistance transposons across related Bacilli genera by horizontal gene movement. PCR amplification using a single primer complementary to the inverted repeat sequence of TnMERI1-like transposons showed that 12 of 65 isolates had a transposon-like structure. There were four types of amplified fragments: Tn5084, Tn5085, Tn(d)MER3 (a newly identified deleted transposon-like fragment) and Tn6294 (a newly identified transposon). Tn(d)MER3 is a 3.5-kb sequence that carries a merRETPA operon with no merB or transposase genes. It is related to the mer operon of Bacillus licheniformis strain FA6-12 from Russia. DNA homology analysis shows that Tn6294 is an 8.5-kb sequence that is possibly derived from Tn(d)MER3 by integration of a TnMERI1-type transposase and resolvase genes and in addition the merR2 and merB1 genes. Bacteria harboring Tn6294 exhibited broad-spectrum mercury resistance to organomercurial compounds, although Tn6294 had only merB1 and did not have the merB2 and merB3 sequences for organomercurial lyases found in Tn5084 of B. cereus strain RC607. Strains with Tn6294 encode mercuric reductase (MerA) of less than 600 amino acids in length with a single N-terminal mercury-binding domain, whereas MerA encoded by strains MB1 and RC607 has two tandem domains. Thus, Tn(d)MER3 and Tn6294 are shorter prototypes for TnMERI1-like transposons. Identification of Tn6294 in Bacillus sp. from Taiwan and in Paenibacillus sp. from Antarctica indicates the wide horizontal dissemination of TnMERI1-like transposons across bacterial species and geographical barriers.

Organomercurials removal by heterogeneous merB genes harboring bacterial strains.

Organomercury lyase (MerB) is a key enzyme in bacterial detoxification and bioremediation of organomercurials. However, the merB gene is often considered as an ancillary component of the mer operon because there is zero to three merB genes in different mer operons identified so far. In this study, organomercurials' removal abilities of native mercury-resistant bacteria that have one or multiple merB genes were examined. Each heterogeneous merB genes from these bacteria was further cloned into Escherichia coli to investigate the substrate specificity of each MerB enzyme. The merB1 gene from Bacillus megaterium MB1 conferred the highest volatilization ability to methylmercury chloride, ethylmercury chloride, thimerosal and p-chloromercuribenzoate, while the merB3 from B. megaterium MB1 conferred the fastest mercury volatilization activity to p-chloromercuribenzoate. The substrate specificities among these MerB enzymes show the necessity for selecting the appropriate bacteria strains or MerB enzymes to apply them in bioremediation engineering for cleaning up specific organomercurial contaminations.

Participation of the recA determinant in the transposition of class II transposon mini-TnMERI1.

As an initial step to understand the mobile nature of class II mercury resistance transposon TnMERI1, the effect of the recA gene on translocation of mini-TnMERI1 was evaluated. A higher transposition frequency in the LE392 strain (2.4+/-1.2x10(-5)) than in the recA-deficient DH1 strain (1.2+/-0.8x10(-6)) indicated participation of the recA gene in mini-TnMERI1 transposition. Introduction of the recA gene into the DH1 strain complemented the transposition frequency at the same level as in LE392 and confirmed participation of the recA gene in transposition. However, treatment of cells by stress agents, including irradiation of up to 3000 Jm(-2) UV doses, did not alter the transposition frequency and suggested independence of RecA from the SOS stress response. Further analysis of transconjugants indicated participation of RecA in the resolution of the cointegrate structure of the transposon. These results suggested that RecA is a constitutive cellular factor that increases translocation of mini-TnMERI1 and may participate in dissemination of TnMERI1-like transposons.

Dissemination of TnMERI1-like mercury resistance transposons among Bacillus isolated from worldwide environmental samples.

Fifty-six mercury-resistant (Hg(R)) Bacillus strains were isolated from natural environments at various sites of the world. Southern hybridisation and polymerase chain reaction (PCR) analysis showed that 21 of the 56 isolates have closely related or identical mer operons to that of Bacillus megaterium MB1. These 21 isolates displayed a broad-spectrum mercury resistance and volatilised Hg(0). PCR amplification with a single primer and restriction fragment length polymorphism analysis showed that these 21 isolates had TnMERI1-like class II transposons. These transposons can be classified into Tn5084, Tn5085, or TnMERI1. From these results, at least three types of class II mercury resistance transposons exist in Hg(R)Bacillus and these transposons may contribute the worldwide distribution and horizontal dissemination of the mer operons among Bacillus strains in natural environments.

Diversity of mercury resistance determinants among Bacillus strains isolated from sediment of Minamata Bay.

Thirty mercury-resistant (Hg R) Bacillus strains were isolated from mercury-polluted sediment of Minamata Bay, Japan. Mercury resistance phenotypes were classified into broad-spectrum (resistant to inorganic Hg(2+) and organomercurials) and narrow-spectrum (resistant to inorganic Hg(2+) and sensitive to organomercurials) groups. Polymerase chain reaction (PCR) product sizes and the restriction nuclease site maps of mer operon regions from all broad-spectrum Hg R Bacillus were identical to that of Bacillus megaterium MB1. On the other hand, the PCR products of the targeted merP (extracellular mercury-binding protein gene) and merA (intracellular mercury reductase protein gene) regions from the narrow-spectrum Hg R Bacillus were generally smaller than those of the B. megaterium MB1 mer determinant. Diversity of gene structure configurations was also observed by restriction fragment length polymorphism (RFLP) profiles of the merA PCR products from the narrow-spectrum Hg R Bacillus. The genetic diversity of narrow-spectrum mer operons was greater than that of broad-spectrum ones.

Characterization of two regulatory genes of the mercury resistance determinants from TnMERI1 by luciferase-based examination.

The broad-spectrum mercury resistance transposon, TnMERI1, of Bacillus megaterium strain MB1, contains three proposed operator/promoter (O/P) transcriptional start sites and two regulatory genes (merR1 and merR2). A series of luciferase (lux)-based transcriptional fusion plasmids were studied in Escherichia coli to show that both merR1 and merR2 gene products repressed transcription from O/PmerB3, O/PmerR1, and O/PmerR2 under uninduced conditions. Derepression occurred when the merR1 gene was present and Hg(2+) functioned as an inducer. In the presence of organomercurial compounds, basal transcription of merB3 was needed to produce inorganic Hg(2+) as the inducer of expression regulated by MerR1 at O/PmerB3. The presence of merR2 repressed transcription from all three O/Pmer sites under both non-induced conditions and when inorganic Hg(2+) or organomercurials were added. These results show that MerR1 functions as a repressor in the absence of Hg(2+) and as an activator in the presence of Hg(2+), while MerR2 functions as a repressor.