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1.
Cell ; 186(13): 2911-2928.e20, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37269832

RESUMO

Animals with complex nervous systems demand sleep for memory consolidation and synaptic remodeling. Here, we show that, although the Caenorhabditis elegans nervous system has a limited number of neurons, sleep is necessary for both processes. In addition, it is unclear if, in any system, sleep collaborates with experience to alter synapses between specific neurons and whether this ultimately affects behavior. C. elegans neurons have defined connections and well-described contributions to behavior. We show that spaced odor-training and post-training sleep induce long-term memory. Memory consolidation, but not acquisition, requires a pair of interneurons, the AIYs, which play a role in odor-seeking behavior. In worms that consolidate memory, both sleep and odor conditioning are required to diminish inhibitory synaptic connections between the AWC chemosensory neurons and the AIYs. Thus, we demonstrate in a living organism that sleep is required for events immediately after training that drive memory consolidation and alter synaptic structures.


Assuntos
Caenorhabditis elegans , Odorantes , Animais , Caenorhabditis elegans/fisiologia , Olfato , Sono/fisiologia , Sinapses/fisiologia
2.
Macromol Biosci ; 23(1): e2200314, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36200651

RESUMO

The delivery of nucleic acids relies on vectors that condense and encapsulate their cargo. Especially nonviral gene delivery systems are of increasing interest. However, low transgene expression levels and limited tolerability of these systems remain a challenge. The improvement of nucleic acid delivery using depolymerized chitosan-polyethylenimine DNA complexes (dCS-PEI/DNA) is investigated. The secore complexes are further combined with chitosan-based shells and functionalized with polyethylene glycol (PEG) and cell penetrating peptides. This modular approach allows to evaluate the effect of functional shell components on physicochemical particle characteristics and biological effects. The optimized ternary complex combines a core-dCS-linear PEI/DNA complex with a shell consisting of dCS-PEG-COOH, which results in improved nucleic acid encapsulation, cellular uptake and transfection potency in human hepatoma HuH-7cells and murine primary hepatocytes. Effects on transgene expression are confirmed in wild-type mice following retrograde intrabiliary infusion. After administration of only 100 ng complexed DNA, ternary complexes induced a high reporter gene signal for three days. It is concluded that ternary coreshell structured nanoparticles comprising functionalized chitosan can be used for in vitro andin vivo gene delivery.


Assuntos
Quitosana , Nanopartículas , Camundongos , Humanos , Animais , Quitosana/farmacologia , Quitosana/química , Polietilenoimina/farmacologia , Polietilenoimina/química , Transfecção , Técnicas de Transferência de Genes , DNA/genética , Nanopartículas/química , Polietilenoglicóis/farmacologia , Polietilenoglicóis/química
3.
Chron Respir Dis ; 19: 14799731211073348, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35041553

RESUMO

Objectives: Adherence to Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) treatment is variable in the inpatient setting. This study evaluates appropriateness of therapy in patients admitted to an academic medical center for AECOPD. Methods: This was a single-center, retrospective, observational study. The primary endpoint was proportion of patients who received appropriate AECOPD treatment within 24 h. Secondary endpoints included mean length of stay (LOS) and time to administration (TTA) of pharmacotherapy, 30-day readmission rates, and proportions of various ancillary care received. Data were analyzed using descriptive and inferential statistics. Results: Of 533 screened admissions, 163 were included. Of those included, 55% (n = 90) received guideline-based therapy within 24 h of presentation. This group had significantly shorter mean LOS (3.48 ± 2.61 vs 4.53 ± 3.40 days, p = .026), fewer COPD-related readmissions (7 vs 14, p = .036), and numerically fewer all-cause readmissions (14 vs 19, p = .11). Mean LOS and TTA were 3.95 ± 3.02 days and 8.47 ± 12.77 h, respectively. Discussion: Timely and guideline-based delivery of medications was associated with shorter length of stay and fewer COPD-related readmissions. Establishing a standardized care plan through order set implementation may be one strategy to improve care and outcomes in AECOPD patients.


Assuntos
Hospitalização , Doença Pulmonar Obstrutiva Crônica , Humanos , Tempo de Internação , Readmissão do Paciente , Estudos Retrospectivos
4.
Med Dosim ; 47(1): 103-109, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34756493

RESUMO

Advances in magnetic resonance linear accelerators (MR-Linacs) allow for superior visualization of soft tissue to guide online adaptive replanning for precise radiotherapy delivery. Elekta Unity MR-Linacs (Elekta AB, Stockholm, Sweden) provides 2 plan adaptation approaches, adapt-to-position (ATP), plan reoptimization based on the reference CT with the iso-shift measured from daily MR scans, and adapt-to-shape (ATS), full plan reoptimization based on the re-contoured daily MR scans. Our study aims to close the gap in knowledge regarding the use of the ATP technique in the treatment of head and neck (HN) cancers through the analysis of accumulated dose of daily ATP plans to organs at risk (OARs). Daily accumulated doses of 8 HN patients using deformable registration were analyzed to estimate the actual delivered dose versus the planned dose to evaluate the impact from daily anatomical changes and setup uncertainties. This process was completed through the collection of doses to OARs which were chosen based on the rigidity and size of the organ and the substantial dose it received. Results showed that the actual dose delivered to some OARs was significantly higher than the originally planned dose and was more pronounced in structures that were within the high-dose gradient for some subdisease sites. These findings suggest that the ATS approach should be used for plan adaptation in some specific HN diseases where OARs receive substantial dose with anatomy changes that could not be accounted for by the ATP approach. We also investigated the possibility of predicting the actual delivered dose at an early stage of the treatment course, with the intention of exploring a possibly more optimal alternative for planning through the combination of ATP and ATS approaches throughout treatment.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Imageamento por Ressonância Magnética , Órgãos em Risco , Aceleradores de Partículas , Dosagem Radioterapêutica
5.
Proc Biol Sci ; 288(1944): 20202851, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33529564

RESUMO

Noise pollution is commonly associated with human environments and mounting evidence indicates that noise has a variety of negative effects on wildlife. Noise has also been linked to cognitive impairment in humans and because many animals use cognitively intensive processes to overcome environmental challenges, noise pollution has the potential to interfere with cognitive function in animals living in urban areas or near roads. We experimentally examined how road traffic noise impacts avian cognitive performance by testing adult zebra finches (Taeniopygia guttata) on a battery of foraging tasks in the presence or absence of traffic noise playback. Here, we show that traffic noise reduces cognitive performance, including inhibitory control, motor learning, spatial memory and social learning, but not associative colour learning. This study demonstrates a novel mechanism through which anthropogenic noise can impact animals, namely through cognitive interference, and suggests that noise pollution may have previously unconsidered consequences for animals.


Assuntos
Tentilhões , Ruído dos Transportes , Animais , Cognição , Ruído dos Transportes/efeitos adversos , Vocalização Animal
6.
J AOAC Int ; 103(5): 1268-1276, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33241400

RESUMO

Testing milk for antibiotics before acceptance into dairies is required by the U.S. Pasteurized Milk Ordinance. Technological advances in tests have reduced screening times and improved detection accuracy. This work describes the validation of the Charm Rapid One Step Assay Beta-Lactam 30 Second Test according to the U.S. Food and Drug Administration Center for Veterinary Medicine protocol for raw commingled milk. Milk is added to the lateral flow test strip in an incubator/reader to deliver a 30 second result. Independent laboratory validation followed sensitivity, interference, and incurred residue protocols. Sensitivity, in parts per billion (ppb = µg/kg), using a probit curve determined 90% percent detection with 95% confidence, which met National Conference of Interstate Milk Shipments (NCIMS) specifications. Six U.S. approved beta-lactam drugs were detected below, but within 50% of, target/tolerance levels for penicillin G 2.9 ppb, ampicillin 5.9 ppb, amoxicillin 5.8 ppb, cephapirin 13 ppb, cloxacillin 8.1 ppb, and ceftiofur metabolites 73 ppb. No interferences were observed from 33 animal drugs at 100 ppb, somatic cells at 1.2 million/mL, or bacterial levels of >300 000 CFU/mL. Incurred residue detection levels were similar to levels determined with the spiked parent compound. The data support NCIMS that the BL30SEC method met U.S. criteria for testing milk for beta-lactams.


Assuntos
Cefapirina , Resíduos de Drogas , Ampicilina/análise , Animais , Antibacterianos/análise , Bovinos , Cefapirina/análise , Resíduos de Drogas/análise , Feminino , Leite/química , Penicilina G/análise , beta-Lactamas/análise
7.
Genetics ; 213(1): 59-77, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31331946

RESUMO

cGMP plays a role in sensory signaling and plasticity by regulating ion channels, phosphodiesterases, and kinases. Studies that primarily used genetic and biochemical tools suggest that cGMP is spatiotemporally regulated in multiple sensory modalities. FRET- and GFP-based cGMP sensors were developed to visualize cGMP in primary cell culture and Caenorhabditis elegans to corroborate these findings. While a FRET-based sensor has been used in an intact animal to visualize cGMP, the requirement of a multiple emission system limits its ability to be used on its own as well as with other fluorophores. Here, we demonstrate that a C. elegans codon-optimized version of the cpEGFP-based cGMP sensor FlincG3 can be used to visualize rapidly changing cGMP levels in living, behaving C. elegans We coexpressed FlincG3 with the blue-light-activated guanylyl cyclases BeCyclOp and bPGC in body wall muscles, and found that the rate of change in FlincG3 fluorescence correlated with the rate of cGMP production by each cyclase. Furthermore, we show that FlincG3 responds to cultivation temperature, NaCl concentration changes, and sodium dodecyl sulfate in the sensory neurons AFD, ASEL/R, and PHB, respectively. Intriguingly, FlincG3 fluorescence in ASEL and ASER decreased in response to a NaCl concentration upstep and downstep, respectively, which is opposite in sign to the coexpressed calcium sensor jRGECO1a and previously published calcium recordings. These results illustrate that FlincG3 can be used to report rapidly changing cGMP levels in an intact animal, and that the reporter can potentially reveal unexpected spatiotemporal landscapes of cGMP in response to stimuli.


Assuntos
GMP Cíclico/metabolismo , Transferência Ressonante de Energia de Fluorescência/métodos , Proteínas de Fluorescência Verde/metabolismo , Optogenética/métodos , Animais , Caenorhabditis elegans , Células Cultivadas , Proteínas de Fluorescência Verde/genética , Guanilato Ciclase/genética , Guanilato Ciclase/metabolismo , Opsinas/genética , Opsinas/metabolismo , Imagem Óptica/métodos , Células Receptoras Sensoriais/citologia , Células Receptoras Sensoriais/metabolismo
8.
Elife ; 62017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28873053

RESUMO

Predators and prey co-evolve, each maximizing their own fitness, but the effects of predator-prey interactions on cellular and molecular machinery are poorly understood. Here, we study this process using the predator Caenorhabditis elegans and the bacterial prey Streptomyces, which have evolved a powerful defense: the production of nematicides. We demonstrate that upon exposure to Streptomyces at their head or tail, nematodes display an escape response that is mediated by bacterially produced cues. Avoidance requires a predicted G-protein-coupled receptor, SRB-6, which is expressed in five types of amphid and phasmid chemosensory neurons. We establish that species of Streptomyces secrete dodecanoic acid, which is sensed by SRB-6. This behavioral adaptation represents an important strategy for the nematode, which utilizes specialized sensory organs and a chemoreceptor that is tuned to recognize the bacteria. These findings provide a window into the molecules and organs used in the coevolutionary arms race between predator and potential prey.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Células Quimiorreceptoras/fisiologia , Neurônios/fisiologia , Streptomyces/patogenicidade , Adaptação Fisiológica , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/microbiologia , Quimiotaxia , Neurônios/citologia , Neurônios/microbiologia , Filogenia , Transdução de Sinais
9.
Am J Health Syst Pharm ; 74(12): 927-931, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28487284

RESUMO

PURPOSE: The adherence to and effectiveness and safety of a timed, electronic, assessment-driven potassium-replacement protocol (TARP) were compared with an electronic nurse-driven replacement protocol (NRP) are reported. METHODS: A retrospective observational study was conducted in a community hospital evaluating protocol adherence, effectiveness, and safety for 2 potassium-replacement protocols. All adults on medical units with an order for potassium replacement per protocol during the 3-month trial periods were reviewed. All patients requiring potassium replacement per protocol were included in the analysis. Adherence to the protocol was assessed by evaluating the dose of potassium administered and performance of reassessments. Effectiveness of the protocol was assessed by evaluating the time to achieve target potassium levels. Safety was assessed by evaluating the route of administration and occurrence of hyperkalemia. RESULTS: A total of 300 patients treated using potassium-replacement protocols required potassium replacement during the study period, with 148 patients in the NRP group requiring 491 instances of potassium replacement. In the TARP group a total of 564 instances requiring potassium replacement corresponded to 152 patients. Of the 491 instances requiring replacement in the NRP group, the correct dose was administered and reassessment performed 117 times (23.8%). Overall adherence (p < 0.05), correct dose given (p < 0.05), average time from blood draw to potassium replacement (p < 0.0001), use of oral replacement (p < 0.05), and time to achieve target potassium level within 12 hours (p < 0.05) were significantly improved in the TARP group. CONCLUSION: The TARP improved the effectiveness and safety of potassium-replacement therapy over the traditional NRP without negatively affecting timeliness of care.


Assuntos
Protocolos Clínicos , Monitoramento de Medicamentos/métodos , Prescrição Eletrônica , Hidratação/métodos , Potássio/sangue , Monitoramento de Medicamentos/instrumentação , Feminino , Hidratação/instrumentação , Hospitais Comunitários/métodos , Humanos , Masculino , Potássio/administração & dosagem , Estudos Retrospectivos , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Equilíbrio Hidroeletrolítico/fisiologia
10.
J Biol Chem ; 291(12): 6483-93, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26801612

RESUMO

Mitochondrial dysfunction is one of the major contributors to neurodegenerative disorders including Parkinson disease. The mitochondrial permeability transition pore is a protein complex located on the mitochondrial membrane. Under cellular stress, the pore opens, increasing the release of pro-apoptotic proteins, and ultimately resulting in cell death. MicroRNA-7 (miR-7) is a small non-coding RNA that has been found to exhibit a protective role in the cellular models of Parkinson disease. In the present study, miR-7 was predicted to regulate the function of mitochondria, according to gene ontology analysis of proteins that are down-regulated by miR-7. Indeed, miR-7 overexpression inhibited mitochondrial fragmentation, mitochondrial depolarization, cytochrome c release, reactive oxygen species generation, and release of mitochondrial calcium in response to 1-methyl-4-phenylpyridinium (MPP(+)) in human neuroblastoma SH-SY5Y cells. In addition, several of these findings were confirmed in mouse primary neurons. Among the mitochondrial proteins identified by gene ontology analysis, the expression of voltage-dependent anion channel 1 (VDAC1), a constituent of the mitochondrial permeability transition pore, was down-regulated by miR-7 through targeting 3'-untranslated region of VDAC1 mRNA. Similar to miR-7 overexpression, knockdown of VDAC1 also led to a decrease in intracellular reactive oxygen species generation and subsequent cellular protection against MPP(+). Notably, overexpression of VDAC1 without the 3'-UTR significantly abolished the protective effects of miR-7 against MPP(+)-induced cytotoxicity and mitochondrial dysfunction, suggesting that the protective effect of miR-7 is partly exerted through promoting mitochondrial function by targeting VDAC1 expression. These findings point to a novel mechanism by which miR-7 accomplishes neuroprotection by improving mitochondrial health.


Assuntos
MicroRNAs/genética , Interferência de RNA , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Regiões 3' não Traduzidas , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Expressão Gênica , Ontologia Genética , Humanos , Potencial da Membrana Mitocondrial , Camundongos Endogâmicos C57BL , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Membranas Mitocondriais/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Tamanho Mitocondrial , Espécies Reativas de Oxigênio/metabolismo , Canal de Ânion 1 Dependente de Voltagem/genética
11.
J Phys Chem B ; 118(2): 547-56, 2014 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-24341749

RESUMO

Molecular simulations of lipids and surfactants require accurate parameters to reproduce and predict experimental properties. Previously, a united atom (UA) chain model was developed for the CHARMM27/27r lipids (Hénin, J., et al. J. Phys. Chem. B. 2008, 112, 7008-7015) but suffers from the flaw that bilayer simulations using the model require an imposed surface area ensemble, which limits its use to pure bilayer systems. A UA-chain model has been developed based on the CHARMM36 (C36) all-atom lipid parameters, termed C36-UA, and agreed well with bulk, lipid membrane, and micelle formation of a surfactant. Molecular dynamics (MD) simulations of alkanes (heptane and pentadecane) were used to test the validity of C36-UA on density, heat of vaporization, and liquid self-diffusion constants. Then, simulations using C36-UA resulted in accurate properties (surface area per lipid, X-ray and neutron form factors, and chain order parameters) of various saturated- and unsaturated-chain bilayers. When mixed with the all-atom cholesterol model and tested with a series of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)/cholesterol mixtures, the C36-UA model performed well. Simulations of self-assembly of a surfactant (dodecylphosphocholine, DPC) using C36-UA suggest an aggregation number of 53 ± 11 DPC molecules at 0.45 M of DPC, which agrees well with experimental estimates. Therefore, the C36-UA force field offers a useful alternative to the all-atom C36 lipid force field by requiring less computational cost while still maintaining the same level of accuracy, which may prove useful for large systems with proteins.


Assuntos
Lipídeos/química , Simulação de Dinâmica Molecular , Tensoativos/química , Colesterol/química , Dimiristoilfosfatidilcolina/química , Bicamadas Lipídicas/química , Micelas , Fosforilcolina/análogos & derivados , Fosforilcolina/química
12.
Spine Deform ; 2(5): 392-398, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27927338

RESUMO

STUDY DESIGN: Clinical case series. OBJECTIVE: To characterize the postoperative course and histopathology of peri-implant tissue of adolescent idiopathic scoliosis patients who experienced postoperative development of an aseptic soft tissue reaction, with granulomas adjacent to the sublaminar polyethylene terephthalate strap-titanium clamp used in Zimmer's Universal Clamp (UC) spinal fixation system after spinal surgery. BACKGROUND SUMMARY: The UC was designed for use with spinal deformity procedures in place of pedicle screws, hooks, or sublaminar wiring in fusion constructs. Recent studies of the UC lack emphasis on implant-related postoperative complications. METHODS: A total of 26 consecutive patients who underwent spinal deformity correction for scoliosis were reviewed for implant-related postoperative complications. Histology, scanning electron microscopy with energy-dispersive X-ray spectroscopy, fractional culture/biopsy, and Gram stain examination of the peri-implant tissue of patients with complications was performed. RESULTS: The authors reviewed 26 cases for correction of scoliosis. Two patients with adolescent idiopathic scoliosis who used the UC experienced implant-related complications with development of an aseptic soft tissue reaction with granulomas adjacent to the sublaminar polyethylene terephthalate straps-titanium clamp mechanism of the UC 8 months after AIS correction surgery. There were no signs or symptoms of wound infection. Gram stain revealed no organisms. There were many neutrophils and the surface of the wound revealed rare Staphylococcus aureus but the deep portions of the wounds were negative for organisms. Histopathology revealed extensive granulation tissue and histiocytes with engulfed birefringent particles or debris, and scanning electron microscopy with energy-dispersive X-ray spectroscopy analysis revealed macrophages containing many particles identified as titanium. CONCLUSIONS: adolescent idiopathic scoliosis patients who use the novel UC construct may develop postoperative foreign-body reaction.

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