Summary The basal ganglia were originally thought to be associated purely with motor control. However, dysfunction and pathology of different regions and circuits are now known to give rise to many ...clinical manifestations beyond the association of basal ganglia dysfunction with movement disorders. Moreover, disorders that were thought to be caused by dysfunction of the basal ganglia only, such as Parkinson's disease and Huntington's disease, have diverse abnormalities distributed not only in the brain but also in the peripheral and autonomic nervous systems; this knowledge poses new questions and challenges. We discuss advances and the unanswered questions, and ways in which progress might be made.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In this study, we combined linkage analysis with whole-exome sequencing of two individuals to identify candidate causal variants in a moderately-sized UK kindred exhibiting autosomal-dominant ...inheritance of craniocervical dystonia. Subsequent screening of these candidate causal variants in a large number of familial and sporadic cases of cervical dystonia led to the identification of a total of six putatively pathogenic mutations in ANO3, a gene encoding a predicted Ca2+-gated chloride channel that we show to be highly expressed in the striatum. Functional studies using Ca2+ imaging in case and control fibroblasts demonstrated clear abnormalities in endoplasmic-reticulum-dependent Ca2+ signaling. We conclude that mutations in ANO3 are a cause of autosomal-dominant craniocervical dystonia. The locus DYT23 has been reserved as a synonym for this gene. The implication of an ion channel in the pathogenesis of dystonia provides insights into an alternative mechanism that opens fresh avenues for further research.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Paroxysmal dyskinesia can be subdivided into three clinical syndromes: paroxysmal kinesigenic dyskinesia or choreoathetosis, paroxysmal exercise-induced dyskinesia, and paroxysmal non-kinesigenic ...dyskinesia. Each subtype is associated with the known causative genes PRRT2, SLC2A1 and PNKD, respectively. Although separate screening studies have been carried out on each of the paroxysmal dyskinesia genes, to date there has been no large study across all genes in these disorders and little is known about the pathogenic mechanisms. We analysed all three genes (the whole coding regions of SLC2A1 and PRRT2 and exons one and two of PNKD) in a series of 145 families with paroxysmal dyskinesias as well as in a series of 53 patients with familial episodic ataxia and hemiplegic migraine to investigate the mutation frequency and type and the genetic and phenotypic spectrum. We examined the mRNA expression in brain regions to investigate how selective vulnerability could help explain the phenotypes and analysed the effect of mutations on patient-derived mRNA. Mutations in the PRRT2, SLC2A1 and PNKD genes were identified in 72 families in the entire study. In patients with paroxysmal movement disorders 68 families had mutations (47%) out of 145 patients. PRRT2 mutations were identified in 35% of patients, SLC2A1 mutations in 10%, PNKD in 2%. Two PRRT2 mutations were in familial hemiplegic migraine or episodic ataxia, one SLC2A1 family had episodic ataxia and one PNKD family had familial hemiplegic migraine alone. Several previously unreported mutations were identified. The phenotypes associated with PRRT2 mutations included a high frequency of migraine and hemiplegic migraine. SLC2A1 mutations were associated with variable phenotypes including paroxysmal kinesigenic dyskinesia, paroxysmal non-kinesigenic dyskinesia, episodic ataxia and myotonia and we identified a novel PNKD gene deletion in familial hemiplegic migraine. We found that some PRRT2 loss-of-function mutations cause nonsense mediated decay, except when in the last exon, whereas missense mutations do not affect mRNA. In the PNKD family with a novel deletion, mRNA was truncated losing the C-terminus of PNKD-L and still likely loss-of-function, leading to a reduction of the inhibition of exocytosis, and similar to PRRT2, an increase in vesicle release. This study highlights the frequency, novel mutations and clinical and molecular spectrum of PRRT2, SLC2A1 and PNKD mutations as well as the phenotype-genotype overlap among these paroxysmal movement disorders. The investigation of paroxysmal movement disorders should always include the analysis of all three genes, but around half of our paroxysmal series remain genetically undefined implying that additional genes are yet to be identified.
Abstract
Background
To investigate the association between frailty, Parkinson’s disease (PD), and the probability of prodromal Parkinson’s disease (prodromal PD) in Greek community-dwelling older ...individuals.
Methods
Parkinson’s disease diagnosis was reached through standard clinical research procedures. Probability of prodromal PD was calculated according to the International Parkinson and Movement Disorder Society’s research criteria for PD-free participants. Frailty was evaluated according to definitions of the phenotypic and multidomain approach. Logistic and linear regression models were performed to investigate associations between frailty (predictor) and the probability of prodromal PD, either continuous or dichotomous (≥30% probability score), or PD (outcome).
Results
Data from 1765 participants aged 65 and older were included in the present analysis. Parkinson’s disease and prodromal PD prevalence were 1.9% and 3.0%, respectively. Compared to nonfrail participants, those who were frail, as identified with either the Fried frailty phenotype or Frailty Index had approximately 4 (odds ratio OR 4.09, 95% confidence interval CI 1.54–10.89) and 12 times (OR 12.16, 95% CI 5.46–27.09) higher odds of having a PD diagnosis, respectively. Moreover, compared to the nonfrail, frail participants as identified with either the Fried frailty phenotype or Frailty Index had 2.8 (OR 2.83, 95% CI 1.09–7.37) and 8.3 times (OR 8.39, 95% CI 4.56–15.42) higher odds of having possible/probable prodromal PD, respectively.
Conclusions
Frailty status was associated with prodromal PD and PD, suggesting common characteristics or underlying mechanisms of these conditions. Although prospective studies are warranted, acknowledging the possible association of frailty, PD, and prodromal PD may improve their clinical management.
, a fungal pathogen that causes gray mold, is damaging more than 200 plant species, and especially tomato. Photosystem II (PSII) responses in tomato (
L.) leaves to
spore suspension application were ...evaluated by chlorophyll fluorescence imaging analysis. Hydrogen peroxide (H
O
) that was detected 30 min after
application with an increasing trend up to 240 min, is possibly convening tolerance against
at short-time exposure, but when increasing at relative longer exposure, is becoming a damaging molecule. In accordance, an enhanced photosystem II (PSII) functionality was observed 30 min after application of
, with a higher fraction of absorbed light energy to be directed to photochemistry (Φ
). The concomitant increase in the photoprotective mechanism of non-photochemical quenching of photosynthesis (NPQ) resulted in a significant decrease in the dissipated non-regulated energy (Φ
), indicating a possible decreased singlet oxygen (
O
) formation, thus specifying a modified reactive oxygen species (ROS) homeostasis. Therefore, 30 min after application of
spore suspension, before any visual symptoms appeared, defense response mechanisms were triggered, with PSII photochemistry to be adjusted by NPQ in a such way that PSII functionality to be enhanced, but being fully inhibited at the application spot and the adjacent area, after longer exposure (240 min). Hence, the response of tomato PSII to
, indicates a hormetic temporal response in terms of "stress defense response" and "toxicity", expanding the features of hormesis to biotic factors also. The enhanced PSII functionality 30 min after
application can possible be related with the need of an increased sugar production that is associated with a stronger plant defense potential through the induction of defense genes.