Loss of primary cilia and dopaminergic neuroprotection in pathogenic LRRK2-driven and idiopathic Parkinson's disease.

Activating LRRK2 mutations cause Parkinson's disease. Previously, we showed that cholinergic interneurons and astrocytes but not medium spiny neurons of the dorsal striatum lose primary cilia in LRRK2 mutant mice. Single nucleus RNA sequencing shows that cilia loss in cholinergic interneurons correlates with higher LRRK2 expression and decreased glial derived neurotrophic factor transcription. Nevertheless, much higher LRRK2 expression is seen in medium spiny neurons that have normal cilia in mice and humans. In parallel with decreased striatal dopaminergic neurite density, LRRK2 G2019S neurons show increased autism-linked CNTN5 adhesion protein expression; glial cells show significant loss of ferritin heavy chain. Human striatal tissue from LRRK2 pathway mutation carriers and idiopathic Parkinson's disease show similar cilia loss in cholinergic interneurons and astrocytes and overall loss of such neurons. These data strongly suggest that loss of cilia in specific striatal cell types decreases neuroprotection for dopamine neurons in mice and human Parkinson's disease.

Municipal solid waste generation and its compositional assessment for efficient and sustainable infrastructure planning in an intermediate city of Pakistan.

It is imperative to design and operate sustainable solid waste management (SWM) systems in cities based on the results of waste amount and characterization study (WACS). In this work, WACS was conducted and results were used to design an SWM system for an intermediate city of Pakistan. The study revealed that about 110 tons of solid waste per day is generated with a per capita rate of 0.337 kg/day. Around 51.2% of mixed municipal solid waste (MSW) is organic in nature and its non-scientific disposal is resulting in higher greenhouse gas (GHG) emissions. It was also found that more than 80% of valuables are taken away by the informal sector during the transfer of MSW from the generation source to the dumping site. Ultimate analyses showed that the moisture content (MC) and carbon to nitrogen (C:N) ratio were 64.23% and 51.14%, respectively. Proximate analysis revealed that moisture and calorific values were 57 % and 3505 BTU/lb., respectively. Based on these results, a material sorting facility (MSF) was proposed, with an estimated investment cost of US $3.64 million. However, the efficiency of the existing collection system is limited to 32 % only. In order to improve the collection efficiency (>90 %), an additional investment of US $1.638 million was estimated with an operations and maintenance (O&M) cost of US $19.25 per ton. Existing non-scientific MSW disposal practices contribute 32,079.61 CO2e tons/year of GHG emissions. The proposed MSF followed by composting is estimated to reduce GHG emissions by 38% to 19,722.38 CO2e tons/year.

Treatment and Prevention of Cardiovascular Implantable Electronic Device (CIED) Infections.

An expanded role for cardiac implantable electronic devices (CIEDs) in recent decades reflects an aging population and broader indications for devices, including both primary prevention and management of dysrhythmias. CIED infection is one of the most important device-related complications and has a major impact on mortality, quality of life, healthcare utilization, and cost. Unfortunately, the investigation and management of CIED infection remain complex, often necessitating complete and timely removal of the device and leads in order to eradicate the infection. In addition, the translation of knowledge from an extensive literature to a disparate group of medical practitioners has often been inadequate. This review of CIED infection management highlights the significant advances made during the past decade, including diagnostic criteria, advanced imaging, and next-generation sequencing for culture-negative cases or those in which uncertainty remains. We also outline the role and indication for powered lead extraction, the process of antibiotic choice and treatment duration, considerations related to the timing and location for reimplantation, and preimplantation risk stratification and associated interventions to reduce the risk of CIED infection.

L'élargissement du rôle des dispositifs électroniques cardiaques implantables (DECI) au cours des dernières décennies reflète le vieillissement de la population et les indications plus vastes des dispositifs, notamment dans la prévention primaire et la prise en charge des dysrythmies. Les infections liées aux DECI sont l'une des plus importantes complications liées aux dispositifs et ont des conséquences majeures sur la mortalité, la qualité de vie, l'utilisation et les coûts des soins de santé. Malheureusement, le dépistage et la prise en charge des infections liées aux DECI demeurent complexes et nécessitent souvent le retrait complet et rapide du dispositif et des sondes en vue d'éradiquer l'infection. De plus, l'application des connaissances issues d'une vaste littérature à un groupe disparate de médecins praticiens a souvent été inadéquate. La présente revue sur la prise en charge des infections liées aux DECI illustre les avancées importantes réalisées au cours de la dernière décennie, notamment les critères diagnostiques, l'imagerie avancée et le séquençage de prochaine génération des cas à culture négative ou de ceux pour lesquels des incertitudes demeurent. Nous avons aussi décrit le rôle et les indications d'extraction des sondes fonctionnelles, le processus du choix des antibiotiques et de la durée du traitement, les considérations relatives au moment et au lieu de la réimplantation, et la stratification du risque en préimplantation et les interventions associées afin de réduire le risque d'infections liées aux DECI.

Pathogenic LRRK2 control of primary cilia and Hedgehog signaling in neurons and astrocytes of mouse brain.

Activating LRRK2 mutations cause Parkinson's disease, and pathogenic LRRK2 kinase interferes with ciliogenesis. Previously, we showed that cholinergic interneurons of the dorsal striatum lose their cilia in R1441C LRRK2 mutant mice (Dhekne et al., 2018). Here, we show that cilia loss is seen as early as 10 weeks of age in these mice and also in two other mouse strains carrying the most common human G2019S LRRK2 mutation. Loss of the PPM1H phosphatase that is specific for LRRK2-phosphorylated Rab GTPases yields the same cilia loss phenotype seen in mice expressing pathogenic LRRK2 kinase, strongly supporting a connection between Rab GTPase phosphorylation and cilia loss. Moreover, astrocytes throughout the striatum show a ciliation defect in all LRRK2 and PPM1H mutant models examined. Hedgehog signaling requires cilia, and loss of cilia in LRRK2 mutant rodents correlates with dysregulation of Hedgehog signaling as monitored by in situ hybridization of Gli1 and Gdnf transcripts. Dopaminergic neurons of the substantia nigra secrete a Hedgehog signal that is sensed in the striatum to trigger neuroprotection; our data support a model in which LRRK2 and PPM1H mutant mice show altered responses to critical Hedgehog signals in the nigrostriatal pathway.

Canadian Heart Rhythm Society Task Force Report on Physician Training and Maintenance of Competency for Cardiovascular Implantable Electronic Device Therapies: Executive Summary.

Physicians engaged in cardiovascular implantable electronic device (CIED)-related practice come from diverse training backgrounds with variable degrees of CIED implant training. The objective of the Canadian Heart Rhythm Society Task Force on CIED Implant Training was to establish a common structure and content for training programs in CIED implantation, related activities and maintenance of competency. This executive summary presents the essence of the report with key recommendations included, with the complete version made available in a linked supplement. The goals are to ensure that future generations of CIED implanters are better prepared for continuously evolving CIED practice and quality care for all Canadians.

Locus coeruleus in memory formation and Alzheimer's disease.

Catecholamine neurons of the locus coeruleus (LC) in the dorsal pontine tegmentum innervate the entire neuroaxis, with signaling actions implicated in the regulation of attention, arousal, sleep-wake cycle, learning, memory, anxiety, pain, mood, and brain metabolism. The co-release of norepinephrine (NE) and dopamine (DA) from LC terminals in the hippocampus plays a role in all stages of hippocampal-memory processing. This catecholaminergic regulation modulates the encoding, consolidation, retrieval, and reversal of hippocampus-based memory. LC neurons in awake animals have two distinct firing modes: tonic firing (explorative) and phasic firing (exploitative). These two firing modes exert different modulatory effects on post-synaptic dendritic spines. In the hippocampus, the firing modes regulate long-term potentiation (LTP) and long-term depression, which differentially regulate the mRNA expression and transcription of plasticity-related proteins (PRPs). These proteins aid in structural alterations of dendritic spines, that is, structural long-term potentiation (sLTP), via expansion and structural long-term depression (sLTD) via contraction of post-synaptic dendritic spines. Given the LC's role in all phases of memory processing, the degeneration of 50% of the LC neuron population occurring in Alzheimer's disease (AD) is a clinically relevant aspect of disease pathology. The loss of catecholaminergic regulation contributes to dysfunction in memory processes along with impaired functions associated with attention and task completion. The multifaceted role of the LC in memory and general task performance and the close correlation of LC degeneration with neurodegenerative disease progression together implicate it as a target for new clinical assessment tools.

A three-dimensional dementia model reveals spontaneous cell cycle re-entry and a senescence-associated secretory phenotype.

A hexanucleotide repeat expansion on chromosome 9 open reading frame 72 (C9orf72) is associated with familial amyotrophic lateral sclerosis (ALS) and a subpopulation of patients with sporadic ALS and frontotemporal dementia. We used inducible pluripotent stem cells from neurotypic and C9orf72+ (C9+) ALS patients to derive neuronal progenitor cells. We demonstrated that C9+ and neurotypic neuronal progenitor cells differentiate into neurons. The C9+ neurons, however, spontaneously re-expressed cyclin D1 after 12 weeks, suggesting cell cycle re-engagement. Gene profiling revealed significant increases in senescence-associated genes in C9+ neurons. Moreover, C9+ neurons expressed high levels of mRNA for CXCL8, a chemokine overexpressed by senescent cells, while media from C9+ neurons contained significant levels of CXCL8, CXCL1, IL13, IP10, CX3CL1, and reactive oxygen species, which are components of the senescence-associated secretory phenotype. Thus, re-engagement of cell cycle-associated proteins and a senescence-associated secretory phenotype could be fundamental components of neuronal dysfunction in ALS and frontotemporal dementia.

Quality specifications and their daily application to evaluate the accuracy of reference measurements for serum concentrations of 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2.

BACKGROUND: Reference measurement procedures (RMP) have rigorous accuracy specifications. For total 25-hydroxyvitamin D, 25(OH)D, bias ≤1.7% and CV ≤5% are recommended. These quality specifications are impractical for minor analytes, such as 25(OH)D2. Furthermore, documentation on RMP quality performance specifications for the individual 25(OH)D metabolites and their daily application are missing. METHODS: To assess accuracy, we used zeta-scores. Daily, 5-10 specimens (duplicate) and 3 reference materials (singleton or duplicate) were measured for 25(OH)D3 and 25(OH)D2 using JCTLM-accepted LC-MS/MS RMPs. Protocols were repeated on 3-4 occasions to generate campaign results. We used separate zeta-score acceptability criteria for daily (≤|2|) and campaign (≤|1|) evaluations. Allowable imprecision was determined experimentally. RESULTS: Across 7 campaigns, unacceptable daily zeta-scores required repeating 2 runs for 25(OH)D3 and 5 runs for 25(OH)D2. Hence, the zeta-scores of acceptable reference material results indicated high accuracy. The allowable imprecision for the RMPs was ≤5% (daily) and ≤ 3% (campaign) for 25(OH)D3 and ≤ 7% (daily) and ≤ 4% (campaign) for 25(OH)D2, respectively. CONCLUSIONS: Using zeta-scores and experimentally derived imprecision, we developed a straightforward approach to assess the acceptability of individual 25(OH)D reference measurements, providing also much-needed practical accuracy specifications for 25(OH)D2.

Bidirectional modulation of Alzheimer phenotype by alpha-synuclein in mice and primary neurons.

α-Synuclein (αSyn) histopathology defines several neurodegenerative disorders, including Parkinson's disease, Lewy body dementia, and Alzheimer's disease (AD). However, the functional link between soluble αSyn and disease etiology remains elusive, especially in AD. We, therefore, genetically targeted αSyn in APP transgenic mice modeling AD and mouse primary neurons. Our results demonstrate bidirectional modulation of behavioral deficits and pathophysiology by αSyn. Overexpression of human wild-type αSyn in APP animals markedly reduced amyloid deposition but, counter-intuitively, exacerbated deficits in spatial memory. It also increased extracellular amyloid-ß oligomers (AßOs), αSyn oligomers, exacerbated tau conformational and phosphorylation variants associated with AD, and enhanced neuronal cell cycle re-entry (CCR), a frequent prelude to neuron death in AD. Conversely, ablation of the SNCA gene encoding for αSyn in APP mice improved memory retention in spite of increased plaque burden. Reminiscent of the effect of MAPT ablation in APP mice, SNCA deletion prevented premature mortality. Moreover, the absence of αSyn decreased extracellular AßOs, ameliorated CCR, and rescued postsynaptic marker deficits. In summary, this complementary, bidirectional genetic approach implicates αSyn as an essential mediator of key phenotypes in AD and offers new functional insight into αSyn pathophysiology.

Indocyanine Green Angiography to Prognosticate Healing of Foot Ulcer in Critical Limb Ischemia: A Novel Technique.

BACKGROUND: To predict wound healing in patients with critical limb ischemia (CLI) is an ongoing issue. Current methods such as ankle-brachial index (ABI), color Doppler and transcutaneous oxygen pressure (TCPO2), and computed tomography angiography are lacking in demonstrating regional perfusion. Indocyanine green angiography (ICGA) has the potential to provide regional perfusion information lacking in other methods. This study was conducted to demonstrate successes of revascularization procedure in CLI patients based on ICGA data. METHODS: A total of 47 patients with grade 2 or grade 3 University of Texas Wound Classification System ischemic foot ulcer undergoing lower limb revascularization procedure were included in this study, from July 2014 to May 2016. ICGA with intravenous 0.1 mg/kg of 0.1% indocyanine green dye was performed before and after revascularization procedure. ICGA data maximum unit, blush time, and blush rate were compared between prerevascularization and postrevascularization data, along with ABI and TCPO2. RESULTS: Out of 47 patients (45 males and 2 females), 43 underwent endovascular revascularization and 4 underwent open procedure. Of all, 76.6% of patients were diabetic and 46.8% were hypertensive. Also, 31.9% had coronary artery disease, 21.2% had history of cerebrovascular disease, 23% had chronic kidney disease, and 74.4% were chronic smokers. A total of 37 patients' ulcer healed completely on follow-up with significant improvement (P < 0.05) in preoperative and postoperative ABI, TCPO2, and ICGA data. Ten patients' ulcer did not heal in the follow-up period. In those 10 patients, preoperative and postoperative ABI and TCPO2 improved, but ICGA data were not improved postoperatively (P > 0.05). CONCLUSIONS: ICGA is an evolving tool to quantify regional perfusion in CLI. ICGA parameters provide qualitative real-time visual images of perfusion in area of interest as well as quantitative information of perfusion.

mTOR and neuronal cell cycle reentry: How impaired brain insulin signaling promotes Alzheimer's disease.

A major obstacle to presymptomatic diagnosis and disease-modifying therapy for Alzheimer's disease (AD) is inadequate understanding of molecular mechanisms of AD pathogenesis. For example, impaired brain insulin signaling is an AD hallmark, but whether and how it might contribute to the synaptic dysfunction and neuron death that underlie memory and cognitive impairment has been mysterious. Neuron death in AD is often caused by cell cycle reentry (CCR) mediated by amyloid-ß oligomers (AßOs) and tau, the precursors of plaques and tangles. We now report that CCR results from AßO-induced activation of the protein kinase complex, mTORC1, at the plasma membrane and mTORC1-dependent tau phosphorylation, and that CCR can be prevented by insulin-stimulated activation of lysosomal mTORC1. AßOs were also shown previously to reduce neuronal insulin signaling. Our data therefore indicate that the decreased insulin signaling provoked by AßOs unleashes their toxic potential to cause neuronal CCR, and by extension, neuron death.

Classification and Surgical Repair of Injuries Sustained During Transvenous Lead Extraction.

BACKGROUND: Injuries to cardiac and venous structures during pacemaker and defibrillator lead extraction are serious complications that have been studied poorly. The incidence of these injuries is unknown but likely underestimated. No systematic multicenter review of these injuries or their management has been undertaken. METHODS AND RESULTS: We interrogated our mandatory administrative database for all excimer laser extractions that sustained a cardiac or venous injury in the province of British Columbia. Injuries were classified according to presentation and compared with respect to nature of injury, type of repair, utilization of cardiopulmonary bypass, and outcome. Of 1082 excimer laser extractions over 19 years, 33 sustained an injury (3.0%). The majority of injuries occurred in women (21/33; 63.6%), and median age of oldest lead extracted was 10.8 (7.5, 12.2) years. A type 1 presentation, defined as circulatory collapse, was found in 12/33 patients (36.4%). A type 2 presentation, defined as progressive hypotension responsive to treatment, was found in 20/33 patients (60.6%). Over half the patients had a moderate or large injury, and cardiopulmonary bypass was required in 13 patients with extensive injury. Despite the presence of devastating injuries, the immediate availability of aggressive salvage measures resulted in a survival of 87.9% of patients at 30 days. CONCLUSIONS: The immediate availability of a cardiovascular surgeon, perfusionist, and cardiopulmonary bypass pump facilitates lifesaving repair of injuries sustained during laser lead extraction. The size and complexity of injury correlates closely with the presentation, blood loss, and need for cardiopulmonary bypass to facilitate repair.

Tau: The Center of a Signaling Nexus in Alzheimer's Disease.

Tau is a microtubule-associated protein whose misfolding, hyper-phosphorylation, loss of normal function and toxic gain of function are linked to several neurodegenerative disorders, including Alzheimer's disease (AD). This review discusses the role of tau in amyloid-ß (Aß) induced toxicity in AD. The consequences of tau dysfunction, starting from the axon and concluding at somadendritic compartments, will be highlighted.

A novel homozygous mutation disrupting the initiation codon in the SLURP1 gene underlies mal de Meleda in a consanguineous family.

Mal de Meleda (MDM) is a palmoplantar keratoderma (PPK), characterized by hyperkeratosis of the palms and soles, and keratotic skin lesions. Patients with MDM can develop perioral erythema, keratotic and lichenoid plaques over the joints (including the elbows and knees), nail abnormalities, joint contractures and stiffness, brachydactyly, sclerodactyly, pseudoainhum, and malodorous maceration. MDM is associated with mutations in the SLURP1 gene. We report a consanguineous family in which MDM was inherited in an autosomal recessive manner. Genotyping using microsatellite markers established linkage in the family to the SLURP1 gene, which has been mapped previously to chromosome 8q24.3. Sequence analysis revealed a homozygous missense mutation (c.2T>C, p.Met1Thr) in affected family members. Molecular docking studies using a ZDOCK server predicted disruption of binding of the mutant variant to its target α7-nAChR. This study further supports the previously reported findings that homozygous mutations in the SLURP1 gene cause MDM.

Phytopythium: molecular phylogeny and systematics.

The genus Phytopythium (Peronosporales) has been described, but a complete circumscription has not yet been presented. In the present paper we provide molecular-based evidence that members of Pythium clade K as described by Lévesque & de Cock (2004) belong to Phytopythium. Maximum likelihood and Bayesian phylogenetic analysis of the nuclear ribosomal DNA (LSU and SSU) and mitochondrial DNA cytochrome oxidase subunit 1 (COI) as well as statistical analyses of pairwise distances strongly support the status of Phytopythium as a separate phylogenetic entity. Phytopythium is morphologically intermediate between the genera Phytophthora and Pythium. It is unique in having papillate, internally proliferating sporangia and cylindrical or lobate antheridia. The formal transfer of clade K species to Phytopythium and a comparison with morphologically similar species of the genera Pythium and Phytophthora is presented. A new species is described, Phytopythium mirpurense.

Genetic variants in the tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) do not contribute but Death Receptor (DR4) genes may contribute to susceptibility to head and neck cancer in Pakistani population.

TRAIL mediated signaling in cancer cells has emerged as one amongst the most deeply studied molecular phenomenon. Recent breakthroughs have shown that overexpression of anti-apoptotic proteins, inactivation of pro-apoptotic proteins, transcriptional downregulation of TRAIL, DR4/DR5, degradation of DR/DR5 are some of the mechanisms which dramatically abrogate TRAIL induced apoptosis in cancer cells. Data obtained through genetic studies has highlighted highly polymorphic nature of DR4 and in accordance with this concept, we investigated the association between Head and Neck Cancer and polymorphisms in TRAIL (1595 C/T) and DR4 (C626G and A1322G) gene. We selected 100 patients with Head and Neck Cancer and 100 healthy, sex and age matched volunteers randomly. C626G and A1322G in DR4 gene were analyzed using Polymerase Change Reaction (PCR) - Restriction Fragment Length Polymorphism (RFLP) and Amplification Refractory Mutation System (ARMS) techniques respectively. For TRAIL gene 1595 C>T genotypes, there was no statistically significant role of homozygous CC or TT in Head and Neck cancer. CC was 58% in patients and 49% in controls. CT was 30% in patients and 43% in controls. TT was 12% in patients and 8% in controls. Allele frequency for C was noted to be 0.73 (patients) and 0.705 (controls), p-value (1). For T, 0.025 (patients) and 0.001(controls), p-value (0.88). The genotyping for DR4 gene 626 C>G polymorphism was done for 100 head and neck cancer patients and 100 age and sex matched healthy controls. All the genotypes for the polymorphism were in Hardy-Weinberg Equilibrium. For DR4626 C>G genotype, CC was 10% in patients and 2% in controls. GC was 63% in patients and 40% in controls. GG was 27% in patients and 58% in controls. Interestingly, in DR4 genotyping, CC was predisposing factor and GG acted as a protective factor. Allele frequency for C was noted to be 0.41 (patients) and 0.22 (controls), p-value (0.81). For G, 0.585 (patients) and 0.78 (controls), p-value (0.867). For the A1322G polymorphism, TT was 23% in patients and 36% in controls with a p-value 0.09 (table 6). CT was statistically significant in patients (45%) and controls (28%), p-value 0.04. CC was non-significant in patients (32%) and controls (36%), p-value 0.62 (table 6). C allele was 0.45% in patients and 0.5% in controls. T allele was 0.54% in patients and 0.5% in controls. Future studies must converge on somatic mutations, epigenetic mutations and expression analysis of TRAIL and DR4 to get a step closer to individualized medicine.

Early failure of the Biotronik Linox implantable cardioverter defibrillator lead.

INTRODUCTION: The Linox and Durata implantable cardioverter defibrillator (ICD) leads were introduced to British Columbia (BC) in 2008. We determined their performance and the potential risk factors for lead failure in a large population-based patient registry. METHODS AND RESULTS: We used the BC Cardiac Registry, a mandatory Governmental database of ICD implants, to identify all recipients of Linox and Durata leads in BC between October 2008 and April 2012, and those subsequently undergoing reoperation. Lead failure was defined as recurrent nonphysiological high-rate sensing unrelated to external electromagnetic interference or T-wave oversensing; a sudden rise in impedance unrelated to perforation or lead dislodgement; or abnormal lead parameters with definite evidence of lead fracture or insulation failure. We determined the estimated cumulative lead survival by the Kaplan-Meier method, and the risk factors for lead failure in a proportional hazards model. Over a median of 39 (27-50) months, the Linox failed more frequently than the Durata (16/477 [3.4%] vs. 4/838 [0.4%]; P < 0.001), and had a significantly lower estimated cumulative survival (91.6 [80.6-96.5]% vs. 99.4 [98.4-99.8]% at 5 years; P < 0.0001). Linox failure was characterized by high-rate nonphysiological sensing (11 cases), and/or a sudden impedance rise (7 cases). Insulation failure was clearly confirmed in 6 cases of Linox failure. Female sex was a significant risk factor for Linox failure (adjusted HR = 2.1[1.3-3.4]; P = 0.004). CONCLUSIONS: This multicenter registry indicates a high rate of Linox lead failure, particularly in female patients. Ongoing surveillance of the Linox ICD lead performance is recommended.