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1.
Am J Emerg Med ; 64: 150-154, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36529072

RESUMO

BACKGROUND: Sepsis is a leading cause of death in hospitals requiring prompt recognition and treatment. The sepsis bundle is the cornerstone of sepsis treatment. Studies have evaluated the impact of a sepsis huddle on sepsis bundle compliance but not in sepsis identification. OBJECTIVE: Measure the effect of a multidisciplinary sepsis bedside huddle in the Emergency Department (ED) on sepsis identification and sepsis bundle compliance. METHODS: Retrospective, single-center, cohort study. Pre-huddle patients were identified via Best Practice Advisory (BPA) alert on the electronic medical record from 11/01/2019-3/31/2020. The post-huddle group were patients for whom a sepsis huddle was activated from 11/01/2020-3/31/2021. RESULTS: 116 patients met inclusion criteria and 15 were determined to not have sepsis for a total of 21 pre-huddle and 80 post-huddle patients. Comparing pre-post results, sepsis huddle increased code sepsis activation (10% vs 91%, p < 0.001); sepsis bundle compliance (24% vs 80%, p < 0.001); antibiotics within one hour (33% vs 90%, p < 0.001); culture within one hour (67% vs 95%, p < 0.001), order entry <30 min. (29% vs 86%, p < 0.001); and median order entry time (48 vs. 3 min, p < 0.001). Post-huddle, 80% of order entries were ≤ 20 min. Logistic regression predicting sepsis code found huddle to be the first predictor, (p < 0.0000005). Hour-1 bundle compliance was predicted by physician/physician assistant order ≤30 min (R2 = 0.36, p < 0.0000005). CONCLUSION: Sepsis bedside huddle in the ED improves identification and sepsis bundle compliance. Results suggest increased order entry speed caused bundle improvement.


Assuntos
Sepse , Humanos , Estudos de Coortes , Estudos Retrospectivos , Sepse/terapia , Sepse/tratamento farmacológico , Serviço Hospitalar de Emergência , Antibacterianos/uso terapêutico , Mortalidade Hospitalar , Fidelidade a Diretrizes
2.
Hippocampus ; 29(11): 1101-1113, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31206907

RESUMO

The transition from recreational drug use to addiction involves pathological learning processes that support a persistent shift from flexible, goal-directed to habit behavioral control. Here, we examined the molecular mechanisms supporting altered function in hippocampal (HPC) and dorsolateral striatum (DLS) memory systems following abstinence from repeated cocaine. After 3 weeks of cocaine abstinence (experimenter- or self-administered), we tested new behavioral learning in male rats using a dual-solution maze task, which provides an unbiased approach to assess HPC- versus DLS-dependent learning strategies. Dorsal hippocampus (dHPC) and DLS brain tissues were collected after memory testing to identify transcriptional adaptations associated with cocaine-induced shifts in behavioral learning. Our results demonstrate that following prolonged cocaine abstinence rats show a bias toward the use of an inflexible, habit memory system (DLS) in lieu of a more flexible, easily updated memory system involving the HPC. This memory system bias was associated with upregulation and downregulation of brain-derived neurotrophic factor (BDNF) gene expression and transcriptionally permissive histone acetylation (acetylated histone H3, AcH3) in the DLS and dHPC, respectively. Using viral-mediated gene transfer, we overexpressed BDNF in the dHPC during cocaine abstinence and new maze learning. This manipulation restored HPC-dependent behavioral control. These findings provide a system-level understanding of altered plasticity and behavioral learning following cocaine abstinence and inform mechanisms mediating the organization of learning and memory more broadly.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/biossíntese , Cocaína/administração & dosagem , Objetivos , Hábitos , Hipocampo/metabolismo , Memória/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Inibidores da Captação de Dopamina/administração & dosagem , Hipocampo/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Memória/efeitos dos fármacos , Ratos , Ratos Long-Evans , Autoadministração , Síndrome de Abstinência a Substâncias/genética , Síndrome de Abstinência a Substâncias/metabolismo
3.
Proc Biol Sci ; 285(1893): 20182441, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30963914

RESUMO

Global analyses of biodiversity consistently reveal recurrent patterns of species distributions worldwide. However, unveiling the specific mechanisms behind those patterns remains logistically challenging, yet necessary for reliable biodiversity forecasts. Here, we combine theory and experiments to investigate the processes underlying spatial biodiversity patterns in dendritic, river-like landscapes, iconic examples of highly threatened ecosystems. We used geometric scaling properties, common to all rivers, to show that the distribution of biodiversity in these landscapes fundamentally depends on how ecological selection is modulated across space: while uniform ecological selection across the network leads to higher diversity in downstream confluences, this pattern can be inverted by disturbances when population turnover (i.e. local mortality) is higher upstream than downstream. Higher turnover in small headwater patches can slow down ecological selection, increasing local diversity in comparison to large downstream confluences. Our results show that disturbance-mediated slowing down of competitive exclusion can generate a specific transient signature in terms of biodiversity distribution when applied over a spatial gradient of disturbance, which is a common feature of many river landscapes.


Assuntos
Biodiversidade , Ecossistema , Rios , Modelos Teóricos
4.
Behav Pharmacol ; 28(7): 586-589, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28704276

RESUMO

Psychopharmacology research has amassed substantial evidence for similarities between synthetic cathinones and other commonly abused psychostimulants. Few studies have utilized drug discrimination methods to investigate synthetic cathinones, and the precise neurochemical substrates underlying their interoceptive effects have not been examined. The present study assessed the involvement of D1 and D2 dopaminergic receptors in the stimulus effects of 3,4-methylenedioxypyrovalerone (MDPV) and mephedrone (MEPH) in rats trained to discriminate D-amphetamine. Eight male Sprague-Dawley rats were trained to discriminate 0.5 mg/kg D-amphetamine (AMPH) from saline. Dose-response curves were then generated with AMPH (0.0-1.0 mg/kg), MDPV (0.0-1.0 mg/kg), and MEPH (0.0-2.0 mg/kg). Subsequently, Sch 39166 (0.3 mg/kg) and haloperidol (0.5 mg/kg) were administered in combination with select doses of MDPV and MEPH. Both MDPV and MEPH produced full substitution for AMPH. Sch 39166 produced a downward shift in the MDPV and MEPH dose-response curves and haloperidol produced similar results with MDPV. These preliminary findings indicate that MDPV and MEPH produce interoceptive stimuli that are similar to those produced by AMPH and that D1 and D2 dopamine receptors contribute to these effects. Additional studies are warranted to investigate the contribution of other receptor mechanisms involved in the interoceptive stimuli produced by synthetic cathinones.


Assuntos
Benzodioxóis/farmacologia , Aprendizagem por Discriminação/efeitos dos fármacos , Pirrolidinas/farmacologia , Animais , Benzodioxóis/metabolismo , Estimulantes do Sistema Nervoso Central/farmacologia , Dextroanfetamina/metabolismo , Dextroanfetamina/farmacologia , Dopamina , Antagonistas de Dopamina/farmacologia , Antagonistas dos Receptores de Dopamina D2/metabolismo , Antagonistas dos Receptores de Dopamina D2/farmacologia , Relação Dose-Resposta a Droga , Masculino , Metanfetamina/análogos & derivados , Metanfetamina/farmacologia , Pirrolidinas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D1/antagonistas & inibidores , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Catinona Sintética
5.
Proc Biol Sci ; 283(1838)2016 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-27629038

RESUMO

Ecosystems are linked to neighbouring ecosystems not only by dispersal, but also by the movement of subsidy. Such subsidy couplings between ecosystems have important landscape-scale implications because perturbations in one ecosystem may affect community structure and functioning in neighbouring ecosystems via increased/decreased subsidies. Here, we combine a general theoretical approach based on harvesting theory and a two-patch protist meta-ecosystem experiment to test the effect of regional perturbations on local community dynamics. We first characterized the relationship between the perturbation regime and local population demography on detritus production using a mathematical model. We then experimentally simulated a perturbation gradient affecting connected ecosystems simultaneously, thus altering cross-ecosystem subsidy exchanges. We demonstrate that the perturbation regime can interact with local population dynamics to trigger unexpected temporal variations in subsidy pulses from one ecosystem to another. High perturbation intensity initially led to the highest level of subsidy flows; however, the level of perturbation interacted with population dynamics to generate a crash in subsidy exchange over time. Both theoretical and experimental results show that a perturbation regime interacting with local community dynamics can induce a collapse in population levels for recipient ecosystems. These results call for integrative management of human-altered landscapes that takes into account regional dynamics of both species and resource flows.


Assuntos
Bactérias , Cilióforos , Ecossistema , Modelos Teóricos , Ecologia , Dinâmica Populacional , Fatores de Tempo
6.
J Pediatr ; 168: 88-92, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26340877

RESUMO

OBJECTIVES: To explore the efficacy and safety of intravenous (IV) hydralazine in hospitalized children with hypertension. STUDY DESIGN: Data were retrospectively collected on hospitalized children treated with IV hydralazine. Percent changes in blood pressure (BP) were calculated, and linear regression was used to investigate associations between BP change and pertinent clinical and demographic variables. Bivariate logistic regression was used to investigate associations between the same covariates and the outcomes of ideal clinical response (ICR), a 10%-25% reduction in mean arterial pressure (MAP), and excess response (ER), a 25% reduction in MAP. RESULTS: A total of 141 initial doses of IV hydralazine (median dose, 0.10 mg/kg [IQR, 0.09-0.11; range, 0.02-0.37]) were analyzed. Median age was 8 years (IQR, 2-15; range, 0-24); most patients had renal disease, malignancy, or were organ transplant recipients. The mean MAP reduction was 19% ± 12%. An ICR occurred in 66 patients (47%). Higher initial MAP and increased hydralazine dose were associated with greater percentage decrease in MAP. No association was found between ICR and the covariates of interest; higher initial MAP was associated with greater odds of ICR. ER occurred in 44 children (31%). Among this group, higher initial MAP and higher hydralazine dose were associated with increased odds of ER, and administration of other antihypertensive drugs was associated with decreased odds of ER. Four adverse effects possibly related to IV hydralazine, including 2 episodes of hypotension, were recorded. CONCLUSIONS: IV hydralazine reduced BP in the majority of children. However, a substantial proportion of children experienced potentially excessive BP reduction.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Hidralazina/uso terapêutico , Hipertensão/tratamento farmacológico , Administração Intravenosa , Adolescente , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Criança , Criança Hospitalizada , Pré-Escolar , Feminino , Humanos , Hidralazina/administração & dosagem , Hidralazina/efeitos adversos , Masculino , Estudos Retrospectivos , Adulto Jovem
7.
Am Nat ; 186(5): 623-33, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26655775

RESUMO

Anthropogenic influences on resources and consumers can affect food web regulation, with impacts on trophic structure and ecosystem processes. Identifying how these impacts unfold is challenging because alterations to one or both resources and consumers can similarly transform community structure, especially for intermediate consumers. To date, empirical testing of perturbations on trophic regulation has been limited by the difficulty in separating the direct effect of perturbations on species composition and diversity from those unfolding indirectly via altered feeding pathways. Moreover, disentangling the independent and interactive impacts of covarying stressors that characterize human-altered systems has been an ongoing analytical challenge. We used a large-scale metacommunity experiment in grasslands to test how resource inputs, stand perturbation, and spatial factors affect regulation of insect herbivores in tritrophic grassland food webs. Using path-model comparisons, we observed significant simplification of food web regulation on insect herbivores, shifting from mixed predator-resource regulation in unaltered mainland areas to strictly resource-based regulation with landscape perturbation and fragmentation. Most changes were attributed to homogenization of plant community caused by landscape fragmentation and the deterministic influence of eutrophication that reduced among-patch beta diversity. This led to a simplified food web dominated by fewer but more abundant herbivore taxa. Our work implies that anthropogenic perturbation relating to resources and spatial isolation can transform the regulation of food web diversity, structure, and function.


Assuntos
Ecossistema , Herbivoria , Insetos/fisiologia , Dispersão Vegetal , Animais , Eutrofização , Cadeia Alimentar , Modelos Biológicos , Ontário
8.
Sci Total Environ ; 912: 168836, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38016568

RESUMO

River ecosystems are heavily impacted by multiple stressors, where effects can cascade downstream of point sources. However, a spatial approach to assess the effects of multiple stressors is missing. We assessed the local and downstream effects on litter decomposition, and associated invertebrate communities of two stressors: flow reduction and artificial light at night (ALAN). We used an 18-flow-through mesocosm system consisting of two tributaries, where we applied the stressors, merging in a downstream section. We assessed the changes in decomposition rate and invertebrate community structure in leaf bags. We found no effect of ALAN or its interaction with flow reduction on the litter decomposition or the invertebrate community in the tributaries. Flow reduction alone led to a 14.8 % reduction in decomposition rate in the tributaries. We recorded no effect of flow reduction on the macroinvertebrates community composition in the litter bags. We also observed no effects of the spatial arrangement of the stressors on the litter decomposition and macroinvertebrate community structure downstream. Overall, our results suggest the impact of stressors on litter decomposition and macroinvertebrate communities remained local in our experiment. Our work thus calls for further studies to identify the mechanisms and the conditions under which spatial effects dominate over local processes.


Assuntos
Ecossistema , Poluição Luminosa , Animais , Invertebrados , Rios/química , Folhas de Planta/química
9.
Ecology ; 94(1): 169-79, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23600251

RESUMO

Understanding the impacts of species extinctions on the functioning of food webs is a challenging task because of the complexity of ecological interactions. We report the impacts of experimental species extinctions on the functioning of two food webs of freshwater and marine systems. We used a linear model to partition the variance among the multiple components of the diversity effect (linear group richness, nonlinear group richness, and identity). The identity of each functional group was the best explaining variable of ecosystem functioning for both systems. We assessed the contribution of each functional group in multifunctional space and found that, although the effect of functional group varied across ecosystem functions, some functional groups shared common effects on functions. This study is the first experimental demonstration that functional identity dominates the effects of extinctions on ecosystem functioning, suggesting that generalizations are possible despite the inherent complexity of interactions.


Assuntos
Extinção Biológica , Cadeia Alimentar , Fucus/fisiologia , Invertebrados/fisiologia , Animais , Biodiversidade , Canadá , Conservação dos Recursos Naturais , Água Doce , Invertebrados/classificação , Modelos Biológicos , Oceanos e Mares
10.
Pediatr Transplant ; 17(1): 80-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23240598

RESUMO

Pediatric valganciclovir dosing recommendations have not been extensively validated for prevention or treatment for CMV infection. As such, we performed a pharmacokinetic study to compare different valganciclovir dosing regimens and the potential benefits of individualized dose adjustments in children following organ transplantation. Ganciclovir AUCs were calculated from four plasma drug levels in pediatric SOT recipients aged six months through three yr receiving valganciclovir suspension by mouth. Of the 28 ganciclovir AUC calculations performed, 11 (39%) were outside the therapeutic target range of 40-60 mcg h/L leading to a valganciclovir dose adjustment. Current manufacturer-recommended dosing based on BSA and CrCl was estimated to result in therapeutic AUCs in fewer patients than the simple weight-based formula used in our institution (4 vs. 13; p = 0.017). An AUC calculation using only the two- and five-h measurements was strongly correlated with the AUC using all four time measurements (R(2) = 0.846; p < 0.001). A simple weight-based dosing approach gives a higher probability for therapeutic AUCs compared to the manufacturer-recommended dosing in pediatric transplant patients aged six months through three yr with normal renal function. An AUC calculated using two sample times might allow for fewer blood draws in the future.


Assuntos
Área Sob a Curva , Ganciclovir/análogos & derivados , Transplante de Órgãos/métodos , Administração Oral , Algoritmos , Antivirais/administração & dosagem , Antivirais/farmacocinética , Peso Corporal , Pré-Escolar , Infecções por Citomegalovirus/prevenção & controle , Esquema de Medicação , Ganciclovir/administração & dosagem , Ganciclovir/farmacocinética , Humanos , Lactente , Reprodutibilidade dos Testes , Resultado do Tratamento , Valganciclovir
11.
Curr Biol ; 33(20): R1054-R1057, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37875080

RESUMO

Terrestrial invertebrates are declining globally, yet we still have a poor understanding of how this will influence ecosystem functioning. A new study suggests that the effect might disrupt connections among ecosystem compartments, leading to loss of important ecosystem services.


Assuntos
Ecossistema , Invertebrados , Animais , Ecologia , Biodiversidade
12.
J Perioper Pract ; 33(6): 176-181, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35322698

RESUMO

BACKGROUND: With the current trend to reduce postoperative opioid use to enhance recovery and address perioperative opioid addiction concerns, the challenge of managing pain after total knee arthroplasty has increased. This study examined the effect of adding a preoperative medication regime to a multimodal postoperative analgesia protocol that included regional anaesthesia. MATERIALS AND METHODS: Sixty patients undergoing elective first-time unilateral knee arthroplasty received celecoxib 100mg, gabapentin 600mg and dexamethasone 10mg po one hour before skin incision. They were compared to a sequential retrospective cohort of 49 patients. All patients routinely received acetaminophen 650mg po q6h, ibuprofen 400mg po q8h, patient-controlled opioid analgesia and continuous adductor canal blocks postoperatively. Pain scores and opioid consumption were recorded at 4, 8, 12, 24 and 48h. RESULTS: Pain scores and cumulative opioid use were statistically and clinically significantly reduced at all time points up to 48h. CONCLUSIONS: Combining preoperative oral celecoxib, gabapentin and dexamethasone had a clinically significantly effect in reducing pain scores and opioid use for at least 48h. Most of this effect is probably due to dexamethasone.


Assuntos
Analgésicos Opioides , Artroplastia do Joelho , Humanos , Gabapentina/uso terapêutico , Celecoxib/uso terapêutico , Estudos Retrospectivos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Analgesia Controlada pelo Paciente , Dexametasona/uso terapêutico
13.
Biomed Phys Eng Express ; 8(2)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35021167

RESUMO

External beam radiotherapy often includes the use of field sizes 3 × 3 cm2or less, which can be defined as small fields. Dosimetry is a difficult, yet important part of the radiotherapy process. The dosimetry of small fields has additional challenges, which can lead to treatment inconsistencies if not done properly. Most important is the use of an appropriate detector, as well as the application of the necessary corrections. The International Atomic Energy Agency and the American Association of Physicists in Medicine provide the International Code of Practice (CoP) TRS-483 for the dosimetry of small static fields used in external MV photon beams. It gives guidelines on how to apply small-field correction factors for small field dosimetry. The purpose of this study was to evaluate the impact of inaccurate small-field output factors on clinical brain stereotactic radiosurgery plans with and without applying the small-field correction factors as suggested in the CoP. Small-field correction factors for a Varian TrueBeam linear accelerator were applied to uncorrected relative dose factors. Uncorrected and corrected clinical plans were created with two different beam configurations, 6 MV with a flattening filter (6 WFF) and 6 MV without a flattening filter (6 FFF). For the corrected plans, the planning target volume mean dose was 1.6 ± 0.9% lower with p < 0.001 for 6 WFF and 1.8 ± 1.5% lower with p < 0.001 for 6 FFF. For brainstem, a major organ at risk, the corrected plans had a dose that was 1.6 ± 0.9% lower with p = 0.03 for 6 WFF and 1.8 ± 1.5% lower with p = 0.10 for 6 FFF. This represents a systematic error that should and can be corrected.


Assuntos
Aceleradores de Partículas , Fótons , Encéfalo , Cabeça , Fótons/uso terapêutico , Radiometria , Estados Unidos
14.
Psychopharmacology (Berl) ; 239(12): 3939-3952, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36287213

RESUMO

RATIONALE: Adolescents represent a vulnerable group due to increased experimentation with illicit substances that is often associated with the adolescent period, and because adolescent drug use can result in long-term effects that differ from those caused by drug use initiated during adulthood. OBJECTIVES: The purpose of the present study was to determine the effects of repeated heroin vapor inhalation during adolescence on measures of nociception, and anxiety-like behavior during adulthood in female and male Wistar rats. METHODS: Rats were exposed twice daily to 30 min of heroin vapor from post-natal day (PND) 36 to PND 45. At 12 weeks of age, baseline thermal nociception was assessed across a range of temperatures with a warm-water tail-withdrawal assay. Anxiety-like behavior was assessed in an elevated plus-maze (EPM) and activity was measured in an open-field arena. Starting at 23 weeks of age, baseline thermal nociception was re-assessed, nociception was determined after acute heroin or naloxone injection, and anxiety-like behavior was redetermined in the EPM. RESULTS: Adolescent heroin inhalation altered baseline thermal nociception in female rats at 12 weeks of age and in both female and male rats at ~ 23 weeks. Heroin-treated animals exhibited anxiety-like behavior when tested in the elevated plus-maze, showed blunted heroin-induced analgesia, but exhibited no effect on naloxone-induced hyperalgesia. CONCLUSIONS: The present study demonstrates that heroin vapor inhalation during adolescence produces behavioral and physiological consequences in rats that persist well into adulthood.


Assuntos
Heroína , Nociceptividade , Ratos , Animais , Masculino , Feminino , Ratos Wistar , Heroína/farmacologia , Ansiedade , Naloxona/farmacologia
15.
J Patient Exp ; 9: 23743735221092557, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35434295

RESUMO

Patients with lower educational attainment are underrepresented in inflammatory bowel disease (IBD) research. To increase our understanding of the health care perspectives of patients with less than a university degree, semi-structured interviews were conducted among 23 outpatients at the McGill University Health Centre IBD Centre (Montreal, Canada). Thematic analysis was used to analyze the qualitative data. Perspectives focused on communication with health care professionals, access to care, symptoms and treatment, and outside support. Access to an IBD specialist was the most important aspect of care. Good care, kind and receptive staff, and a lengthy delay to diagnosis were frequently reported experiences. IBD specialists, nurses, and family and friends were most helpful in managing disease. Physical and emotional symptoms, reduced social engagement, and medications were difficult aspects of living with IBD. An ideal IBD clinic would provide access to traditional and non-traditional services and assist with obtaining support to help patients engage in social activities, increase affordability of care, and maintain employment. Study findings may be helpful in designing equitable models of health care delivery.

16.
Pharmacol Biochem Behav ; 202: 173116, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33493547

RESUMO

Advances in drug vapor exposure systems have enabled evaluation of Δ-9-tetrahydrocannabinol (THC) vapor effects in laboratory animals. The purpose of this study was to 1) establish a range of parameters of THC vapor exposure in rats sufficient to produce a behavioral dose-effect curve in a battery of tasks sensitive to THC; and 2) to investigate sex differences in the effects of THC vapor exposure and THC injection (intraperitoneal, IP) on these behaviors in two strains of outbred rats. Male and female Sprague Dawley and Wistar rats (N = 22, 5-6/sex per group) received THC via passive vapor exposure (200 mg/mL; 5 conditions) and IP injection (1-20 mg/kg) in a within subject design. The effects of vaped and injected THC on appetite was determined using progressive ratio responding for food pellets. THC effects on nociception, measured using the tail withdrawal assay, and body temperature were also assessed during a 5-h test period for evaluation of time course of effects. Plasma THC concentrations were assessed after THC vapor and 10 mg/kg IP THC. THC vapor produced exposure-related increases and decreases in motivation to obtain food under the progressive ratio schedule. IP THC (3-20 mg/kg) reduced breakpoints. Vaped and injected THC produced exposure and dose-dependent antinociception and hypothermia. Sex and strain differences in THC effects were also observed. Plasma THC concentrations were higher after 10 mg/kg IP THC (152 ng/mL) compared to the highest vapor exposure condition tested (38 ng/mL), but magnitude of behavioral effects were comparable. THC vapor exposure produced reliable, dose orderly effects on food-maintained behavior, nociception, and body temperature that are comparable to effects of IP THC, although there were differences in the time course of behavioral outcomes.


Assuntos
Analgésicos/administração & dosagem , Apetite/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Dronabinol/administração & dosagem , Hipotermia/induzido quimicamente , Nociceptividade/efeitos dos fármacos , Administração por Inalação , Analgésicos/sangue , Analgésicos/química , Animais , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Dronabinol/sangue , Dronabinol/química , Feminino , Injeções Intraperitoneais , Masculino , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Fatores Sexuais , Volatilização
17.
Orthop J Sports Med ; 8(3): 2325967120905795, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32201706

RESUMO

BACKGROUND: Femoral tunnel positioning in anterior cruciate ligament reconstruction (ACLR) is an intricate procedure that requires highly specific surgical skills. PURPOSE: To report the ability of residents to identify femoral landmarks and the native ACL footprint before and after a structured formal teaching session as a reflection of overall surgical skill training for orthopaedic surgery residents in Canada. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 13 senior orthopaedic residents were asked to identify a femoral landmark and an ACL footprint on ten 3-dimensional (3D)-printed knee models before and after a teaching session during the fall of 2018. The 3D models were made based on actual patients with different anatomic morphologic features. ImageJ software was used to quantify the measurements, which were then analyzed through use of descriptive statistics. RESULTS: Before and after the teaching session, residents attempted to identify a specific anatomic location (bifurcate and intercondylar ridge intersection) with a mean error per participant ranging from 5.00 to 10.95 mm and 4.79 to 12.13 mm in magnitude, respectively. Furthermore, before and after the teaching session, residents identified the specific position to perform the surgical procedure (ACL femoral footprint), with a mean error per participant ranging from 4.58 to 8.80 mm and 3.87 to 11.07 mm in magnitude, respectively. The teaching session resulted in no significant improvement in identification of either the intersection of the bifurcate and intercondylar ridges (P = .9343 in the proximal-distal axis and P = .8133 in the anteroposterior axis) or the center of the femoral footprint (P = .7761 in the proximal-distal axis and P = .9742 in the anteroposterior axis). CONCLUSION: Although a formal teaching session was combined with a hands-on session that entailed real surgical instrumentation and fresh cadaveric specimens, the intervention seemed to have no direct impact on senior residents' performance or their ability to demonstrate the material taught. This puts into question the format and efficacy of present teaching methods. Also, it is possible that the 3D spatial perception required to perform these skills is not something that can be taught effectively through a teaching session or at all. Further investigation is required regarding the effectiveness and application of surgical skill laboratories and simulations on the competencies of orthopaedic residents.

18.
Arthrosc Sports Med Rehabil ; 2(4): e361-e368, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32875301

RESUMO

PURPOSE: To examine the ability of surgeons to identify the osseous landmarks associated with the femoral anterior cruciate ligament (ACL) footprint and locate optimal tunnel placement on 3-dimensional (3D) printed models compared with intraoperative placement. METHODS: Twelve sports fellowship-trained orthopaedic surgeons were asked to identify a femoral landmark and an ACL footprint on 10 different 3D printed knees. The 3D models were made based on 20 real patients with different anatomical morphology who later received ACL reconstructive surgery using independent drilling. ImageJ software was used to quantify the measurements, which were then analyzed using descriptive statistics. RESULTS: Overall, none of the surgeons were able to consistently identify the junction of the bony ridges. The mean error per participant ranged from 2.81 to 7.34 mm in the proximal direction (P = 3.30e-05) and from 2.42 to 8.05 mm in the posterior direction (P =4.88e-12). None of the surgeons were able to appropriately identify the center of the femoral footprint on the anatomic 3D models. The difference between the center of the footprint surgeons identified on the 3D model and the tunnel graft location in surgery was significantly different (P = .0046). On average, the magnitude of the error when the surgeons performed the actual surgery was 3.72 ± 2.43 mm, whereas on the 3D models it was 5.82 ± 1.97 mm. CONCLUSIONS: Experienced sports fellowship-trained orthopaedic surgeons were unable to correctly identify the junction of the intercondylar and bifurcate ridges and the native ACL footprint on 3D models. Operatively placed tunnels were more accurate implying that looking either through a scope or soft-tissue landmarks play a significant role in surgeons ACL footprint localization. CLINICAL RELEVANCE: The graft position for ACL reconstruction plays an important role on the kinematics of the knee. This paper shows that soft tissue landmarks are needed to provide reliable reference points for reconstruction.

20.
Ecology ; 100(4): e02633, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30693474

RESUMO

Moving beyond species count data is an essential step to better understand the effects of environmental perturbations on biodiversity and ecosystem functions, and to eventually better predict the strength and direction of those effects. Here, coupling an integrative path analysis approach with data from an extensive countrywide monitoring program, we tested the main spatial, environmental and anthropogenic drivers of change in the functional structure of aquatic macroinvertebrate communities along the entire Swiss Rhine river catchment. Functional structure was largely driven by inherent altitudinal variation influencing and cascading to regional scaled factors such as land use change and position in the riverine network, which, in turn, transformed local habitat structure variables. Those cascading effects across scales propagated through the biotic community, first affecting prey and, in turn, predators. Our results illustrate how seemingly less important local factors can act as essential transmission belts, propagating through direct and indirect pathways across scales to generate the specific context in which each functional group will strive or not, leading to characteristic landscape wide variations in functional community structure.


Assuntos
Ecossistema , Rios , Animais , Biodiversidade , Monitoramento Ambiental , Invertebrados
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