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1.
Water Res ; 183: 116121, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32877809

RESUMEN

About 25 golf courses in Ontario, Canada have environmental compliance approvals to use reclaimed water for irrigation, where disinfection is confirmed through E. coli limits. A previous study at five Ontario municipal wastewater treatment plants (WWTPs) confirmed that enteric viruses are less susceptible to disinfection than E. coli, when plants provided conventional (secondary or tertiary) treatment and routine (chlorine or UV) disinfection. Here we query whether these four treatment-disinfection scenarios plus 60-day lagoon storage of disinfected effluent would be sufficient to reduce norovirus genogroups I and II (NoV GI and GII) risk of infection to tolerable levels for a golfer who incidentally ingests NoV after handling wet golf balls at a golf course irrigated with reclaimed water. We used our RT-qPCR NoV enumeration datasets from the four treatment-disinfection scenarios above and modeled detected and non-detected NoV by Bayesian inference in 'R'. Monte Carlo simulation included pre-disinfection NoV GI and GII gene copy densities; Ontario WWTP-derived chlorine and UV log10 reductions; literature-derived effluent storage decay parameters and golfer ingested volumes, followed by six different NoV dose-response (DR) models. Quantitative Microbial Risk Assessment (QMRA) results suggest that there is an unacceptable NoV infection risk when using the conservative assumption that all detected NoV particles (RT-qPCR gene copies) are infectious, in both aggregated or disaggregated form. However, after adjusting for PCR target sequences and for infectiousness using data from recently published studies on cultivation of human NoV in human intestinal enteroids, we noted a significant reduction of infection risk. However, this less conservative (i.e., less protective) assumption for water reuse applications such as golf course irrigation may not be corroborated until human NoV are efficiently and routinely grown in cell cultures. In addition, further studies on drivers of NoV risk estimation by DR models are needed, e.g., the extent of NoV particle aggregation resulting from wastewater treatment, as well as the role of immunity. Meantime, regulatory agencies could consider more stringent treatment-disinfection requirements that target enteric viruses rather than E. coli and testing of actual reclaimed irrigation waters.


Asunto(s)
Golf , Norovirus , Teorema de Bayes , Escherichia coli , Humanos , Ontario , Medición de Riesgo , Aguas Residuales , Agua
2.
Front Hum Neurosci ; 14: 61, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32158384

RESUMEN

Accurate localization of complex human experiences such as emotions, dreaming, creativity, and consciousness to specific cerebral structures or neural networks has remained elusive despite technological advances. We report the use of acute deep brain stimulation (DBS) to evoke behavioral and emotional effects by applying electrical stimulation (ES) at various voltage strengths to the basolateral and central subnuclei of the amygdala in addition to the head of hippocampus (HC) for two subjects with medically refractory post-traumatic stress disorder (PTSD). Our results suggest that the amygdala could be a node in a neural network responsible for the generation of complex vivid mental imagery and integrated sensory experiences similar to John Hughlings Jackson's "dreamy state" and "double consciousness," which have been classically associated with temporal lobe epilepsy during uncinate seizures. That we were able to elicit similar vivid, dynamic, complex, bizarre, and original mental imagery with ES in non-epileptic subjects suggests that Jackson's seizure related "dreamy state" and "double consciousness" may arise from heightened innate brain mechanisms with the amygdala acting as a node in the neural network responsible for physiologic dreaming and creative functions. Furthermore, our subjects experienced different emotions with different stimulation strengths at various electrode contacts. Our results suggest that higher voltage stimulation of the amygdala and HC at 4-5 V leads to predominantly negative responses and 2-4 V stimulation showed inversely coupled positive and negative responses of the amygdala in either hemisphere which may imply hemispheric dominance of emotional valences without relation to handedness. Due to the unique and complex responses dependent on location and strength of stimulation, we advise that all patients receiving DBS of the amygdala undergo acute stimulation mapping in a monitored setting before selecting therapeutic parameters for chronic stimulation.

3.
J Water Health ; 17(5): 670-682, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31638019

RESUMEN

In Ontario, Canada, information is lacking on chlorine and ultraviolet (UV) light disinfection performance against enteric viruses in wastewater. We enumerated enteroviruses and noroviruses, coliphages, and Escherichia coli per USEPA methods 1615, 1602, and membrane filtration, respectively, in pre- and post-disinfection effluent at five wastewater treatment plants (WWTPs), with full-year monthly sampling, and calculated log10 reductions (LRs) while WWTPs complied with their monthly geometric mean limit of 200 E. coli/100 mL. Modeling of densities by left-censored estimation and Bayesian inference gave very similar results. Polymerase chain reaction (PCR)-detected enteroviruses and noroviruses were abundant in post-disinfection effluent (mean concentrations of 2.1 × 10+4-7.2 × 10+5 and 2.7 × 10+4-3.6 × 10+5 gene copies (GC)/L, respectively). Chlorine or UV disinfection produced modest LRs for culture- (0.3-0.9) and PCR-detected enteroviruses (0.3-1.3), as well as noroviruses GI + GII (0.5-0.8). Coliphages and E. coli were more susceptible, with LRs of 0.8-3.0 and 2.5, respectively. Sand-filtered effluent produced significantly higher enteric virus LRs (except cultured enteroviruses). Coliphage and human enteric virus densities gave significantly positive correlations using Kendall's Tau test. Enteric viruses are abundant in wastewater effluent following routine chlorine or UV disinfection processes that target E. coli. Coliphages appear to be good indicators for evaluating wastewater disinfection of enteric viruses.


Asunto(s)
Desinfección , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/virología , Teorema de Bayes , Cloro , Escherichia coli , Humanos , Ontario , Rayos Ultravioleta
4.
Epilepsy Behav ; 90: 148-153, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30537670

RESUMEN

BACKGROUND: The complex clinical presentation and progression of Lennox-Gastaut syndrome (LGS) can complicate the accurate diagnosis of this severe, lifelong, childhood-onset epilepsy, often resulting in suboptimal treatment. The Refractory Epilepsy Screening Tool for LGS (REST-LGS) was developed to improve the identification of patients with LGS. METHODS: Using the Modified Delphi Consensus, a group of experts developed and tested the REST-LGS Case Report Form (CRF) comprising 8 criteria (4 major, 4 minor) considered potentially indicative of LGS. Diagnosis-blinded specialist and nonspecialist raters at 2 epilepsy centers applied the CRF to deidentified patient records, including 1:1 records of patients with drug-resistant epilepsy or confirmed LGS. Interrater reliability was measured by Cohen's κ. Diagnosis was then unblinded to reveal common criteria for LGS or drug-resistant epilepsy. Cronbach's α was used to measure internal consistency between raters for all criteria combined. RESULTS: Of 200 patients, 81% to 85% met 1 to 3 major criteria. At both sites, moderate (κ, 0.41-0.60) to good (κ, 0.61-0.80) agreement on most criteria was reached between expert and nonexpert raters. Unblinding revealed that most patients with LGS met 3 major and 2 to 3 minor criteria, while patients with drug-resistant epilepsy met ≤1 major and only 1 to 2 minor criteria. Cronbach's α of raters at both sites was 0.64. CONCLUSIONS: The combined number of major/minor criteria on the CRF may be particularly indicative of LGS. Therefore, the REST-LGS may be a valuable clinical tool in identifying patients requiring further diagnostic evaluation for LGS.


Asunto(s)
Epilepsia Refractaria/diagnóstico , Epilepsia Refractaria/psicología , Síndrome de Lennox-Gastaut/diagnóstico , Síndrome de Lennox-Gastaut/psicología , Registros Médicos , Adulto , Niño , Técnica Delphi , Progresión de la Enfermedad , Epilepsia Refractaria/epidemiología , Electroencefalografía/métodos , Femenino , Humanos , Síndrome de Lennox-Gastaut/epidemiología , Masculino , Reproducibilidad de los Resultados , Método Simple Ciego
5.
Nat Med ; 24(4): 497-504, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29457796

RESUMEN

Genomic analyses of cancer have identified recurrent point mutations in the RNA splicing factor-encoding genes SF3B1, U2AF1, and SRSF2 that confer an alteration of function. Cancer cells bearing these mutations are preferentially dependent on wild-type (WT) spliceosome function, but clinically relevant means to therapeutically target the spliceosome do not currently exist. Here we describe an orally available modulator of the SF3b complex, H3B-8800, which potently and preferentially kills spliceosome-mutant epithelial and hematologic tumor cells. These killing effects of H3B-8800 are due to its direct interaction with the SF3b complex, as evidenced by loss of H3B-8800 activity in drug-resistant cells bearing mutations in genes encoding SF3b components. Although H3B-8800 modulates WT and mutant spliceosome activity, the preferential killing of spliceosome-mutant cells is due to retention of short, GC-rich introns, which are enriched for genes encoding spliceosome components. These data demonstrate the therapeutic potential of splicing modulation in spliceosome-mutant cancers.


Asunto(s)
Neoplasias/tratamiento farmacológico , Neoplasias/genética , Piperazinas/farmacología , Piridinas/farmacología , Empalme del ARN/genética , Bibliotecas de Moléculas Pequeñas/uso terapéutico , Empalmosomas/genética , Administración Oral , Animales , Secuencia de Bases , Humanos , Intrones/genética , Células K562 , Leucemia/genética , Leucemia/patología , Ratones , Mutación , Neoplasias/patología , Piperazinas/administración & dosificación , Piridinas/administración & dosificación , Empalme del ARN/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Carga Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Cancer Res ; 76(11): 3332-9, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27197173

RESUMEN

Chemotherapy-induced peripheral neuropathy is a dose-limiting side effect of many antineoplastic agents, but the mechanisms underlying the toxicities are unclear. At their MTDs, the microtubule-binding drugs paclitaxel and ixabepilone induce more severe neuropathy in mice relative to eribulin mesylate, paralleling their toxicity profiles in clinic. We hypothesized that the severity of their neurotoxic effects might be explained by the levels at which they accumulate in the peripheral nervous system. To test this hypothesis, we compared their pharmacokinetics and distribution in peripheral nerve tissue. After administration of a single intravenous dose, each drug was rapidly cleared from plasma but all persisted in the dorsal root ganglia (DRG) and sciatic nerve (SN) for up to 72 hours. Focusing on paclitaxel and eribulin, we performed a 2-week MTD-dosing regimen, followed by a determination of drug pharmacokinetics, tissue distribution, and multiple functional measures of peripheral nerve toxicity for 4 weeks. Consistent with the acute dosing study, both drugs persisted in peripheral nervous tissues for weeks, in contrast to their rapid clearance from plasma. Notably, although eribulin exhibited greater DRG and SN penetration than paclitaxel, the neurotoxicity observed functionally was consistently more severe with paclitaxel. Overall, our results argue that sustained exposure of microtubule-binding chemotherapeutic agents in peripheral nerve tissues cannot by itself account for their associated neurotoxicity. Cancer Res; 76(11); 3332-9. ©2016 AACR.


Asunto(s)
Apoptosis/efectos de los fármacos , Ganglios Espinales/patología , Microtúbulos/patología , Paclitaxel/farmacología , Enfermedades del Sistema Nervioso Periférico/patología , Nervio Ciático/patología , Animales , Western Blotting , Proliferación Celular , Relación Dosis-Respuesta a Droga , Electrofisiología , Epotilonas/farmacocinética , Epotilonas/farmacología , Femenino , Furanos/farmacocinética , Furanos/farmacología , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Cetonas/farmacocinética , Cetonas/farmacología , Ratones , Ratones Endogámicos BALB C , Microtúbulos/efectos de los fármacos , Microtúbulos/metabolismo , Paclitaxel/farmacocinética , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Enfermedades del Sistema Nervioso Periférico/metabolismo , Nervio Ciático/efectos de los fármacos , Nervio Ciático/metabolismo , Factores de Tiempo , Distribución Tisular , Moduladores de Tubulina/farmacocinética , Moduladores de Tubulina/farmacología
7.
Drug Metab Dispos ; 44(8): 1399-423, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27052879

RESUMEN

Under the guidance of the International Consortium for Innovation and Quality in Pharmaceutical Development (IQ), scientists from 20 pharmaceutical companies formed a Victim Drug-Drug Interactions Working Group. This working group has conducted a review of the literature and the practices of each company on the approaches to clearance pathway identification (fCL), estimation of fractional contribution of metabolizing enzyme toward metabolism (fm), along with modeling and simulation-aided strategy in predicting the victim drug-drug interaction (DDI) liability due to modulation of drug metabolizing enzymes. Presented in this perspective are the recommendations from this working group on: 1) strategic and experimental approaches to identify fCL and fm, 2) whether those assessments may be quantitative for certain enzymes (e.g., cytochrome P450, P450, and limited uridine diphosphoglucuronosyltransferase, UGT enzymes) or qualitative (for most of other drug metabolism enzymes), and the impact due to the lack of quantitative information on the latter. Multiple decision trees are presented with stepwise approaches to identify specific enzymes that are involved in the metabolism of a given drug and to aid the prediction and risk assessment of drug as a victim in DDI. Modeling and simulation approaches are also discussed to better predict DDI risk in humans. Variability and parameter sensitivity analysis were emphasized when applying modeling and simulation to capture the differences within the population used and to characterize the parameters that have the most influence on the prediction outcome.


Asunto(s)
Descubrimiento de Drogas/normas , Industria Farmacéutica/normas , Enzimas/metabolismo , Modelos Teóricos , Preparaciones Farmacéuticas/metabolismo , Animales , Biotransformación , Simulación por Computador , Árboles de Decisión , Descubrimiento de Drogas/métodos , Interacciones Farmacológicas , Humanos , Cinética , Preparaciones Farmacéuticas/química , Medición de Riesgo , Especificidad de la Especie , Especificidad por Sustrato
8.
Case Rep Neurol Med ; 2015: 421563, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26167316

RESUMEN

Brain injury can lead to impaired cortical inhibition of the hypothalamus, resulting in increased sympathetic nervous system activation. Symptoms of paroxysmal sympathetic hyperactivity may include hyperthermia, tachycardia, tachypnea, vasodilation, and hyperhidrosis. We report the case of a 41-year-old man who suffered from a left middle cerebral artery stroke and subsequently developed central fever, contralateral temperature change, and hyperhidrosis. His symptoms abated with low-dose propranolol and then returned upon discontinuation. Restarting propranolol again stopped his symptoms. This represents the first report of propranolol being used for unilateral dysautonomia after stroke. Propranolol is a lipophilic nonselective beta-blocker which easily crosses the blood-brain barrier and may be used to treat paroxysmal sympathetic hyperactivity.

9.
J Morphol ; 276(1): 22-32, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25069818

RESUMEN

Many mammal skulls contain air spaces inside the bones surrounding the nasal chamber including the frontal, maxilla, ethmoid, and sphenoid, all of which are called paranasal sinuses. Within the Carnivora, frontal sinuses are usually present, but vary widely in size and shape. The causes of this variation are unclear, although there are some functional associations, such as a correlation between expanded frontal sinuses and a durophagous diet in some species (e.g., hyenas) or between absent sinuses and semiaquatic lifestyle (e.g., pinnipeds). To better understand disparity in frontal sinus morphology within Carnivora, we quantified frontal sinus size in relationship to skull size and shape in 23 species within Arctoidea, a clade that is ecologically diverse including three independent invasions of aquatic habitats, by bears, otters, and pinnipeds, respectively. Our sampled species range in behavior from terrestrial (rarely or never forage in water), to semiterrestrial (forage in water and on land), to semiaquatic (forage only in water). Results show that sinuses are either lost or reduced in both semiterrestrial and semiaquatic species, and that sinus size is related to skull size and shape. Among terrestrial species, frontal sinus size was positively allometric overall, but several terrestrial species completely lacked sinuses, including two fossorial badgers, the kinkajou (a nocturnal, arboreal frugivore), and several species with small body size, indicating that factors other than aquatic habits, such as space limitations due to constraints on skull size and shape, can limit sinus size and presence.


Asunto(s)
Evolución Biológica , Seno Frontal/anatomía & histología , Mamíferos/anatomía & histología , Animales , Ecosistema , Filogenia
10.
Int J Pharm ; 443(1-2): 9-16, 2013 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-23313921

RESUMEN

Eribulin mesylate (E7389), a tubulin and microtubule inhibitor, has been approved to treat metastatic breast cancer in certain patient populations. A liposomal formulation of E7389, E7389-LF, aims to increase the therapeutic profile of E7389. As determining the free drug concentration is crucial for the assessment of efficacy and toxicity of liposomal drug, in this study, an ultracentrifugation method coupled with LC-MS/MS was developed to separate the free E7389 from liposomal and protein bound E7389. The pharmacokinetics of the free E7389 after dosing either E7389 or E7389-LF was characterized. The concentration ratio of E7389 in ultracentrifuged mice plasma (UCM) vs E7389 in plasma after a 2mg/kg i.v. of E7389 ranged from 54.19% to 65.41%, which was similar to the free fraction in the mouse plasma. The respective concentration ratio of E7389 in UCM vs E7389 in plasma after a 2mg/kg i.v. of E7389-LF ranged from 0.07% to 0.59%, and the exposure, expressed as AUC, of UCM/plasma ratio was determined to be 0.2%. Pharmacokinetic modeling was performed to estimate the release kinetics of E7389 from E7389-LF, and the release was best described by a first order rate constant k(rel) 0.078 h(-1). Sensitivity analysis demonstrated that further decrease the release rate constant by adjusting liposome formulation would lead to decreased C(max) and much longer half-life of UCM E7389, which might result in better efficacy and lower toxicity.


Asunto(s)
Furanos/farmacocinética , Cetonas/farmacocinética , Moduladores de Tubulina/farmacocinética , Animales , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Composición de Medicamentos , Estabilidad de Medicamentos , Furanos/administración & dosificación , Furanos/sangre , Inyecciones Intravenosas , Cetonas/administración & dosificación , Cetonas/sangre , Límite de Detección , Liposomas , Masculino , Ratones , Ratones Endogámicos , Modelos Biológicos , Estructura Molecular , Espectrometría de Masas en Tándem , Factores de Tiempo , Moduladores de Tubulina/administración & dosificación , Moduladores de Tubulina/sangre
11.
Rev Neurol Dis ; 5(3): 109-16, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18838950

RESUMEN

Immune mechanisms play a critical role in systemic disorders (systemic lupus erythematosus, Sjögren's syndrome, Crohn's disease, and sarcoidosis) and in localized central nervous system (CNS) disorders (CNS vasculitis, multiple sclerosis, acute disseminated encephalomyelitis, and encephalitides). Both humoral and cell-mediated mechanisms are involved in the systemic and CNS-limited disorders. Immune mechanisms may also be a factor in a number of epilepsies such as Rasmussen's encephalitis, Lennox-Gastaut syndrome, Landau-Kleffner syndrome, and temporal lobe epilepsy. Immunologic abnormalities are found in routine epilepsy surgical specimens, suggesting a broader role of immunopathology in the etiology of epilepsy. The prevalence and impact of immunopathology in epilepsy syndromes remains to be determined by future research.


Asunto(s)
Enfermedades Autoinmunes del Sistema Nervioso/complicaciones , Sistema Nervioso Central/inmunología , Epilepsia/inmunología , Enfermedades del Sistema Inmune/complicaciones , Microglía/inmunología , Enfermedades Autoinmunes del Sistema Nervioso/inmunología , Sistema Nervioso Central/citología , Epilepsia/clasificación , Epilepsia/complicaciones , Humanos , Enfermedades del Sistema Inmune/inmunología
12.
Epilepsy Behav ; 12(4): 636-43, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18171635

RESUMEN

Revered in some cultures but persecuted by most others, epilepsy patients have, throughout history, been linked with the divine, demonic, and supernatural. Clinical observations during the past 150 years support an association between religious experiences during (ictal), after (postictal), and in between (interictal) seizures. In addition, epileptic seizures may increase, alter, or decrease religious experience especially in a small group of patients with temporal lobe epilepsy (TLE). Literature surveys have revealed that between .4% and 3.1% of partial epilepsy patients had ictal religious experiences; higher frequencies are found in systematic questionnaires versus spontaneous patient reports. Religious premonitory symptoms or auras were reported by 3.9% of epilepsy patients. Among patients with ictal religious experiences, there is a predominance of patients with right TLE. Postictal and interictal religious experiences occur most often in TLE patients with bilateral seizure foci. Postictal religious experiences occurred in 1.3% of all epilepsy patients and 2.2% of TLE patients. Many of the epilepsy-related religious conversion experiences occurred postictally. Interictal religiosity is more controversial with less consensus among studies. Patients with postictal psychosis may also experience interictal hyper-religiosity, supporting a "pathological" increase in interictal religiosity in some patients. Although psychologic and social factors such as stigma may contribute to religious experiences with epilepsy, a neurologic mechanism most likely plays a large role. The limbic system is also often suggested as the critical site of religious experience due to the association with temporal lobe epilepsy and the emotional nature of the experiences. Neocortical areas also may be involved, suggested by the presence of visual and auditory hallucinations, complex ideation during many religious experiences, and the large expanse of temporal neocortex. In contrast to the role of the temporal lobe in evoking religious experiences, alterations in frontal functions may contribute to increased religious interests as a personality trait. The two main forms of religious experience, the ongoing belief pattern and set of convictions (the religion of the everyday man) versus the ecstatic religious experience, may be predominantly localized to the frontal and temporal regions, respectively, of the right hemisphere.


Asunto(s)
Epilepsia/psicología , Religión y Psicología , Espiritualidad , Encéfalo/fisiopatología , Epilepsia/complicaciones , Epilepsia/historia , Historia del Siglo XV , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia Antigua , Historia Medieval , Humanos , Religión , Convulsiones/complicaciones , Convulsiones/psicología
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