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1.
Appl Environ Microbiol ; 86(23)2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-32978132

RESUMEN

This study investigated the use of biofilms to monitor Cryptosporidium in water. Benthic rock and submersible slide biofilms were sampled upstream and downstream of point sources in a suburban watershed in southeastern Pennsylvania. More oocysts were detected in biofilms scraped from rocks downstream than upstream of a wastewater treatment plant (WWTP) (19 versus 5, respectively; n = 1). Although not statistically significant, Cryptosporidium oocysts were detected more frequently, and in greater numbers, in biofilms grown on slides downstream than upstream of this same WWTP (83.3% positive samples [n = 12] versus 45.5% positive samples [n = 11], respectively; P = 0.0567). Similarly, Cryptosporidium oocysts were detected more frequently, and in greater numbers, in rock biofilms collected downstream than upstream of a stormwater outfall impacted by defective sewer laterals (50% positive samples downstream and 17% positive samples upstream; n = 6; P = 0.2207). While oocyst detection data obtained by slide biofilms versus filters did not necessarily agree on a given day, there was no seasonal difference in the frequency of oocyst detection (P > 0.05) or numbers of oocysts detected (P > 0.05) whether the water was monitored by filtration or slide biofilm sampling. Within any given season, there was no difference in the frequency of oocyst detection (P > 0.05) or the numbers of oocysts detected (P > 0.05) whether the water was monitored by filtration or slide biofilm sampling. These data show that oocyst detection in biofilms is comparable to oocyst detection in filtered water samples. Biofilm sampling offers significant cost savings compared to the filtration-based EPA Method 1623.1 and could be used to identify watershed locations at potential risk for increased oocyst loads.IMPORTANCE Monitoring Cryptosporidium occurrence in watersheds that provide drinking water is necessary to determine where limited resources should most effectively be directed to protect consumers from waterborne exposure to pathogenic oocysts. Biofilms are a useful tool to monitor complex watersheds and identify point sources of Cryptosporidium oocyst contamination that need to be managed to protect public health. Compared to EPA Method 1623.1, the cost benefit of using biofilms to monitor for Cryptosporidium contamination will enable utilities to sample water supplies more frequently, and at more locations, than is currently possible given limited operating budgets. Biofilm sampling could be used to identify high-risk regions within a large, complex watershed and the associated water treatment plants at potential risk for increased oocyst loads in the water supply; this information could then be used to select the locations within the watershed where the more expensive EPA Method 1623.1 is warranted.


Asunto(s)
Biopelículas , Cryptosporidium/aislamiento & purificación , Agua Dulce/parasitología , Cryptosporidium/fisiología , Agua Potable/parasitología , Oocistos/aislamiento & purificación , Pennsylvania , Abastecimiento de Agua
2.
Neurogastroenterol Motil ; 36(3): e14728, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38105462

RESUMEN

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative movement disorder with prodromal and highly prevalent gastrointestinal (GI) symptoms, especially constipation. Although PD models suggest gut-brain axis dysfunction, the mechanistic underpinnings and their correlation with GI symptoms are poorly understood. AIM: To examine the bidirectional gut-brain axis function in PD and correlate it with constipation severity, PD duration, and severity. METHODS: Rectal sensory thresholds and afferent cortical evoked potentials (CEP) were assessed using a 4-ring EMG electrode probe. Efferent anal and rectal motor evoked potentials (MEPs) were obtained following transcranial and lumbosacral magnetic stimulation. Bowel symptoms were assessed by prospective stool diary. The CEP and MEP latencies, rectal sensory thresholds, and anorectal sensorimotor data were compared between PD subjects and age-adjusted healthy subjects. KEY RESULTS: Twenty-five PD subjects with constipation (F/M = 6/19) and 20 healthy subjects (F/M = 14/6) were enrolled. The first and pain sensation thresholds were higher in PD subjects than healthy subjects (p < 0.002) but lost significance after adjustment for age. Age-adjusted rectal CEP and right-sided cortico-anal MEP latencies were prolonged in PD subjects compared to healthy subjects (p < 0.04). Also, half (4 of 8) age-adjusted spino-anal and rectal MEP latencies in PD subjects were significantly longer. In multivariate linear analysis, first rectal sensation and right-sided MEP latencies showed moderate correlation with constipation severity. CONCLUSIONS & INFERENCES: Parkinson's disease is associated with significant bidirectional gut-brain axis dysfunction as evidenced by prolonged afferent and efferent neuronal signaling. Constipation severity in PD is correlated to abnormal rectal sensation and lateralized disturbance of efferent brain-gut signaling.


Asunto(s)
Enfermedades Gastrointestinales , Enfermedad de Parkinson , Humanos , Eje Cerebro-Intestino , Enfermedad de Parkinson/complicaciones , Estreñimiento , Recto , Canal Anal
3.
Front Neurol ; 14: 1210103, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37554394

RESUMEN

Background: In pre-clinical animal models of Parkinson's disease (PD), vagus nerve stimulation (VNS) can rescue motor deficits and protect susceptible neuronal populations. Transcutaneous auricular vagus nerve stimulation (taVNS) has emerged as a non-invasive alternative to traditional invasive cervical VNS. This is the first report summarizing the safety, feasibility, and preliminary efficacy of repeated sessions of taVNS in participants with PD. Objectives: To evaluate the feasibility, safety, and possible efficacy of taVNS for motor and non-motor symptoms in mild to moderate PD. Methods: This is a double-blind, sham controlled RCT (NCT04157621) of taVNS in 30 subjects with mild to moderate PD without cognitive impairment. Participants received 10, 1-h taVNS sessions (25 Hz, 200% of sensory threshold, 500 µs pulse width, 60 s on and 30 s off) over a 2-week period. Primary outcome measures were feasibility and safety of the intervention; secondary outcomes included the MDS-UPDRS, cognitive function and self-reported symptom improvement. Results: taVNS treatment was feasible, however, daily in-office visits were reported as being burdensome for participants. While five participants in the taVNS group and three in the sham group self-reported one or more minor adverse events, no major adverse events occurred. There were no group differences on blood pressure and heart rate throughout the intervention. There were no group differences in MDS-UPDRS scores or self-reported measures. Although global cognitive scores remained stable across groups, there was a reduction in verbal fluency within the taVNS group. Conclusions: taVNS was safe, and well-tolerated in PD participants. Future studies of taVNS for PD should explore at-home stimulation devices and optimize stimulation parameters to reduce variability and maximize engagement of neural targets.

4.
Ophthalmology ; 118(3): 548-52, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20920828

RESUMEN

PURPOSE: This article describes the first retinal histopathologic findings in a patient with Susac's syndrome (SS). DESIGN: Observational case report. PARTICIPANT: A 51-year-old white woman diagnosed with SS. METHODS: Eyes from a 51-year-old white woman diagnosed with SS were obtained at autopsy. One retina was dissected and processed for adenosine diphosphatase (ADPase) flat embedding. Selected areas were processed further for transmission electron microscopy. MAIN OUTCOME MEASURES: Histopathologic examination using ADPase flat-embedding technique. RESULTS: There were vaso-occlusive changes in the retinal periphery resulting in small areas of capillary dropout. Cross-sections demonstrated serous filled spaces between the retinal blood vessels and the internal limiting membrane. Lumens adjacent to these spaces appeared compressed and sometimes closed, but without thrombosis. Decreased ADPase activity in some peripheral blood vessels suggested endothelial cell dysfunction and vaso-occlusion. In the optic nerve head, numerous corpora amylacea were observed in the vicinity of capillaries with thickened walls and narrow lumens. Transmission electron microscopy demonstrated thickened and amorphous vascular basal lamina and open endothelial cell junctions in some retinal blood vessels. CONCLUSIONS: The serous deposits with compression of retinal vessel lumens observed histologically probably represent the so-called string of pearls described clinically in SS. Chronic extension of these serous deposits along the vessel wall possibly are the cause of retinal arterial wall plaques as described by Gass and other investigators. In the optic nerve head, corpora amylacea are probably a result of microinfarcts resulting from optic nerve head capillary angiopathy. Accumulation of amorphous material in the basal lamina, loss of viable endothelial cells, and capillary dropout suggest that SS may be an endotheliopathy.


Asunto(s)
Disco Óptico/ultraestructura , Enfermedades del Nervio Óptico/diagnóstico , Enfermedades de la Retina/diagnóstico , Vasos Retinianos/ultraestructura , Síndrome de Susac/diagnóstico , Apirasa/metabolismo , Femenino , Humanos , Microscopía Electrónica de Transmisión , Persona de Mediana Edad , Disco Óptico/enzimología , Enfermedades del Nervio Óptico/enzimología , Enfermedades de la Retina/enzimología , Vasos Retinianos/enzimología
5.
Environ Sci Technol ; 45(12): 5156-63, 2011 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-21615082

RESUMEN

Dechlorane (mirex), Dechlorane Plus (DP), Dechlorane 602 (Dec602), Dechlorane 603 (Dec603), Dechlorane 604 (Dec604), and Chlordecone (Kepone) were analyzed in 16 sediment cores collected in 2007 from the Great Lakes of North America. Results show that Lake Ontario sediments have accumulated mirex, DP, Dec602 and Dec604 in amounts 1 to 2 orders of magnitude higher than other Great Lakes. The chemical inventory decreases log-linearly with increasing latitude (N) and longitude (W) of the sampling locations, but Lake Ontario sites are outliers in the regression against latitude. The regression analyses suggest differences among the analytes with regard to source impact and long-range transport behavior. Temporal trends of input differ among lakes. Most sites in Lake Superior are still receiving increasing fluxes of DP and Dec602, while these have been declining in Lake Ontario from the peak around 1990. The relative abundance of the two DP isomers, represented by f(syn), increases with increasing distance from the potential discharge source in Niagara Falls, NY, suggesting the anti-DP isomer is more vulnerable to degradation during long-range atmospheric transport. Kepone was not detected in the sediments of Lakes Ontario, Erie, and Michigan.


Asunto(s)
Sedimentos Geológicos/química , Hidrocarburos Clorados/análisis , Geografía , Great Lakes Region , Hidrocarburos Clorados/química , Isomerismo , Movimiento (Física)
7.
J Neurochem ; 106(5): 2068-79, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18665889

RESUMEN

Delta-aminolevulinic acid (delta-ALA) is a heme precursor implicated in neurological complications associated with porphyria and tyrosinemia type I. Delta-ALA is also elevated in the urine of animals and patients treated with the investigational drug dichloroacetate (DCA). We postulated that delta-ALA may be responsible, in part, for the peripheral neuropathy observed in subjects receiving DCA. To test this hypothesis, myelinating cocultures of Schwann cells and sensory neurons were exposed to delta-ALA (0.1-1 mM) and analyzed for the expression of neural proteins and lipids and markers of oxidative stress. Exposure of myelinating samples to delta-ALA is associated with a pronounced reduction in the levels of myelin-associated lipids and proteins, including myelin protein zero and peripheral myelin protein 22. We also observed an increase in protein carbonylation and the formation of hydroxynonenal and malondialdehyde after treatment with delta-ALA. Studies of isolated Schwann cells and neurons indicate that glial cells are more vulnerable to this pro-oxidant than neurons, based on a selective decrease in the expression of mitochondrial respiratory chain proteins in glial, but not in neuronal, cells. These results suggest that the neuropathic effects of delta-ALA are attributable, at least in part, to its pro-oxidant properties which damage myelinating Schwann cells.


Asunto(s)
Ácido Aminolevulínico/toxicidad , Ácido Dicloroacético/toxicidad , Vaina de Mielina/efectos de los fármacos , Nervios Periféricos/efectos de los fármacos , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Células de Schwann/efectos de los fármacos , Ácido Aminolevulínico/metabolismo , Animales , Axones/efectos de los fármacos , Axones/metabolismo , Axones/patología , Células Cultivadas , Técnicas de Cocultivo , Relación Dosis-Respuesta a Droga , Radicales Libres/metabolismo , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Ganglios Espinales/fisiopatología , Hemo/biosíntesis , Ratones , Proteínas de la Mielina/efectos de los fármacos , Proteínas de la Mielina/metabolismo , Vaina de Mielina/metabolismo , Vaina de Mielina/patología , Fibras Nerviosas Mielínicas/efectos de los fármacos , Fibras Nerviosas Mielínicas/metabolismo , Fibras Nerviosas Mielínicas/patología , Neuronas Aferentes/efectos de los fármacos , Neuronas Aferentes/metabolismo , Neuronas Aferentes/patología , Neurotoxinas/metabolismo , Neurotoxinas/toxicidad , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Nervios Periféricos/metabolismo , Nervios Periféricos/patología , Enfermedades del Sistema Nervioso Periférico/metabolismo , Enfermedades del Sistema Nervioso Periférico/fisiopatología , Ratas , Células de Schwann/metabolismo , Células de Schwann/patología
8.
Aust N Z J Public Health ; 36(2): 145-52, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22487349

RESUMEN

OBJECTIVE: Using Australian Football League (AFL) matches as a case study, we investigated the frequency, length and content of marketing strategies for sports betting during two specific settings: 1) at stadiums during four live matches; and 2) during eight televised broadcasts of matches. METHODS: Census of sports betting marketing during Round 12 of the 2011 AFL premiership season. RESULTS: Per match, there was an average of 58.5 episodes (median 49.5, s.d 27.8) and 341.1 minutes (median 324.1 minutes and s.d 44.5) of sports betting marketing at stadiums, and 50.5 episodes (median 53.5, s.d 45.2) and 4.8 minutes (median 5.0 minutes, s.d 4.0) during televised broadcasts. A diverse range of marketing techniques were used to: a) embed sports betting within the game; b) align sports betting with fans' overall experience of the game; and c) encourage individuals to bet live during the game. There were very few visible or audible messages (such as responsible gambling or Gambler's Help messages) to counter-frame the overwhelmingly positive messages that individuals received about sports betting during the match. CONCLUSIONS AND IMPLICATIONS: This study raises important questions about the impacts of saturation, integrated and impulse gambling marketing strategies in sporting matches. Future research should explore: 1) how wagering industry marketing strategies may affect the attitudes and behaviours of community sub-groups (e.g. young male sports fans, and children); and 2) which public health and policy strategies, including regulation and harm minimisation messaging, will be effective in responding to wagering industry marketing strategies during sporting matches.


Asunto(s)
Fútbol Americano , Juego de Azar , Mercadotecnía/estadística & datos numéricos , Publicidad/métodos , Publicidad/estadística & datos numéricos , Australia , Femenino , Humanos , Masculino , Mercadotecnía/métodos , Salud Pública , Televisión/estadística & datos numéricos
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