Publications by authors named "Fahn S"

Article Synopsis
  • - Variants in the CTSB gene are linked to an increased risk of Parkinson's disease (PD) and affect the activity of cathepsin B, an enzyme involved in breaking down proteins and regulating cellular processes related to autophagy and lysosome function.
  • - CatB can both degrade the harmful alpha-synuclein protein associated with PD and potentially create shorter versions of it that are more prone to aggregation, complicating its role in PD pathology.
  • - Experiments showed that inhibiting catB disrupts autophagy and lysosomal function, leading to an accumulation of toxic protein aggregates, while activating catB enhances the clearance of these aggregates in cell and neuron models.
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Article Synopsis
  • Variants in the GBA gene, which codes for glucocerebrosidase (GCase), are major genetic risk factors for Parkinson's disease (PD), leading to decreased GCase activity.
  • A genome-wide association study was conducted using two cohorts to identify common variants related to GCase activity, confirming known variants and discovering a new link involving the GAA gene, which encodes for acid alpha-glucosidase.
  • The identified associations suggest that other PD-risk loci may also influence GCase activity, indicating a need for further studies to explore these relationships and their functional implications.
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Background: Studies have suggested that intrinsic auricular muscle zones (IAMZ) stimulation alleviates motor features of Parkinson disease (PD).

Methods: A randomized, blinded, active sham-controlled pilot trial was conducted to evaluate the safety and dose-response-time curve of Earstim using a 3-treatment, 3-period crossover design in PD patients experiencing OFF time on levodopa. Treatments were: short (20-min) IAMZ stimulation; long (60-min) IAMZ stimulation; and 20-min active sham stimulation of non-muscular areas.

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Strabismus, deviation of the ocular alignment, can adversely affect quality of life and activities of daily living. Surgery was the prior standard of care for strabismus, but up to 40% of patients required additional surgeries. This need for more effective and less invasive treatment, along with the convergence of other events such as the development of electromyography, purification of botulinum toxin A, and the finding that injection of botulinum toxin type A could paralyze the hind limbs of chicks, led Dr.

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Background: Several lysosomal genes are associated with Parkinson's disease (PD), yet the association between PD and ARSA remains unclear.

Objectives: To study rare ARSA variants in PD.

Methods: To study rare ARSA variants (minor allele frequency < 0.

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Objective: To assess for TDP-43 deposits in brains with and without a LRRK2 G2019S mutation.

Background: LRRK2 G2019S mutations have been associated with parkinsonism and a wide range of pathological findings. There are no systematic studies examining the frequency and extent of TDP-43 deposits in neuropathological samples from LRRK2 G2019S carriers.

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Background: Several lysosomal genes are associated with Parkinson's disease (PD), yet the association between PD and , which encodes for the enzyme arylsulfatase A, remains controversial.

Objectives: To evaluate the association between rare variants and PD.

Methods: To study possible association of rare variants (minor allele frequency<0.

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Article Synopsis
  • - The study aimed to create a global cohort of individuals with Parkinson's disease (PD) linked to specific genetic variants, aiming to improve the understanding and treatment of monogenic PD.
  • - Researchers collected data from 3,888 participants across 92 centers in 42 countries, including 3,185 diagnosed with PD and 703 unaffected individuals, which highlighted a total of 269 distinct pathogenic variants.
  • - This initiative not only established the largest international genetic PD cohort but also provided quality-controlled clinical and genetic data to foster further research collaboration.
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The association between glucocerebrosidase, encoded by GBA, and Parkinson's disease (PD) highlights the role of the lysosome in PD pathogenesis. Genome-wide association studies in PD have revealed multiple associated loci, including the GALC locus on chromosome 14. GALC encodes the lysosomal enzyme galactosylceramidase, which plays a pivotal role in the glycosphingolipid metabolism pathway.

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Background: With the explosion of COVID-19 globally, it was unclear if people with Parkinson's disease (PD) were at increased risk for severe manifestations or negative outcomes.

Objectives: To report on people with PD who had suspected or confirmed COVID-19 to understand how COVID-19 manifested in PD patients.

Methods: We surveyed PD patients who reported COVID-19 to their Movement Disorders specialists at Columbia University Irving Medical Center and respondents from an online survey administered by the Parkinson's Foundation that assessed COVID-19 symptoms, general clinical outcomes and changes in motor and non-motor PD symptoms.

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Background: PLXNA1 encodes for Plexin-A, a transmembrane protein expressed in the developing nervous system. Mutations in this gene have been associated with developmental delay but have not been previously associated with the development of parkinsonism.

Objectives: To describe the case of a 38-year-old patient with developmental delay who developed parkinsonism later in life.

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Background: "Ondine's curse" or central hypoventilation, induces an apparently spontaneous failure of automatic respiratory drive, henceforth necessitating a conscious effort to breathe and sleep induced hypoventilation. It is typically seen in congenital central hypoventilation syndrome, but may be acquired.

Objectives: To highlight Ondine's curse as part of frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17) secondary to microtubule associated protein tau () variants.

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Objective: This study is based on long-term follow-up of participants in a randomized double-blind sham surgery-controlled trial (1995-1999) designed to determine the effectiveness of implantation of human embryonic mesencephalic tissue containing dopamine neuron precursors into the brains of patients with advanced Parkinson's disease (PD). We investigated differences between long-term survivors and nonsurvivors at baseline in order to contribute to information regarding optimal patient selection for upcoming stem cell trials.

Method: Forty participants were randomly assigned to receive either neural implantation or sham surgery.

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Purpose: To investigate the effect of PLXNA1 variants on the phenotype of patients with autosomal dominant and recessive inheritance patterns and to functionally characterize the zebrafish homologs plxna1a and plxna1b during development.

Methods: We assembled ten patients from seven families with biallelic or de novo PLXNA1 variants. We describe genotype-phenotype correlations, investigated the variants by structural modeling, and used Morpholino knockdown experiments in zebrafish to characterize the embryonic role of plxna1a and plxna1b.

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Cell transplants are being developed for patients with Parkinson disease (PD) who have insufficient benefit with standard medical treatment. We describe the clinical features of five patients who developed persistent dyskinesias after fetal dopaminergic tissue transplantation. All had levodopa-induced dyskinesias preoperatively.

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Purpose: Up to 25% of patients diagnosed as idiopathic Parkinson's disease (IPD) have an atypical parkinsonian syndrome (APS). We had previously validated an automated image-based algorithm to discriminate between IPD, multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). While the algorithm was accurate with respect to the final clinical diagnosis after long-term expert follow-up, its relationship to the initial referral diagnosis and to the neuropathological gold standard is not known.

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The LRRK2 p.G2019S Parkinson's disease (PD) variant is associated with elevated glucocerebrosidase (GCase) activity in peripheral blood. We aimed to evaluate the association of other LRRK2 variants with PD and its association with GCase activity.

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Background: Homozygous and compound heterozygous variants in glucocerebrosidase (GBA) can cause Gaucher disease (GD), whereas heterozygous variants increase the risk of developing Parkinson's disease (PD). GD patients display altered peripheral immune proteins. However, it is unknown if these are altered in GBA carriers with PD.

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Oleh Hornykiewicz (November 17, 1926–May 26, 2020), by demonstrating the loss of dopamine neurons in Parkinson’s disease, introducing the effort to treat the disorder with L-DOPA, and other innovative research, improved the lives of countless individuals and transformed neurology and medical science. Here we celebrate the life and great achievements of an outstanding scientist.

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Genome-wide association studies (GWAS) have identified numerous loci associated with Parkinson's disease. The specific genes and variants that drive the associations within the vast majority of these loci are unknown. We aimed to perform a comprehensive analysis of selected genes to determine the potential role of rare and common genetic variants within these loci.

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Rare mutations in genes originally discovered in multigenerational families have been associated with increased risk of Parkinson's disease (PD). The involvement of rare variants in DNAJC13, UCHL1, HTRA2, GIGYF2, and EIF4G1 loci has been poorly studied or has produced conflicting results across cohorts. However, they are still being often referred to as "PD genes" and used in different models.

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Background: Biallelic PRKN mutation carriers with Parkinson's disease (PD) typically have an earlier disease onset, slow disease progression, and, often, different neuropathology compared to sporadic PD patients. However, the role of heterozygous PRKN variants in the risk of PD is controversial.

Objectives: Our aim was to examine the association between heterozygous PRKN variants, including single-nucleotide variants and copy-number variations (CNVs), and PD.

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