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1.
Forensic Sci Int ; 341: 111515, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36371981

RESUMEN

Bloodstained fabrics found at crime scenes are likely to have had processing treatments, such as dyeing or printing, but the effect of the treatments on bloodstain morphology is not always considered. In order to study the effect of digital printing on bloodstain morphology, drip stains were created from five impact velocities (1.9-5.4 ms-1) on three different mass per unit areas (88-226 g/m²) of 100% cotton calico which had been digitally printed using reactive dye. Across all three printed fabrics, the bloodstains appeared visually similar, and no correlation was found between the dry bloodstain area and the impact velocity. When comparing the bloodstains on the printed fabric to those which had been created previously on the same fabric in a dyed and not-coloured state, the dry bloodstains on the printed fabric were statistically significantly larger (e.g. for the calico with the lightest mass per unit area, mean dry bloodstain area was 126.6, 64.4 and 44.3 mm² for the printed, dyed and not-coloured fabrics respectively). Examination of the larger bloodstains on the printed calico with the micro computed tomography scanner and scanning electron microscope, suggested that the printing process increased the wettability of the fabric, so the blood could spread more easily on the surface. This allowed the blood to coat the yarns, and wick into them before wicking along the intra-yarn spaces. The results presented in this paper showed that care must be taken when examining bloodstains at crime scenes. Depending on the fabric and the processing of the fabric the size of the blood stains may not increase with impact velocity as wicking may result in a larger bloodstain from a lower velocity. The bloodstain on the penetrated face of the fabric may be larger than on the impacted face and the same fabrics with different processing will produce different blood stain sizes and shapes.


Asunto(s)
Manchas de Sangre , Microtomografía por Rayos X , Textiles , Acción Capilar , Impresión Tridimensional
2.
Pediatr Qual Saf ; 7(3): e555, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35720871

RESUMEN

Introduction: Variation in antibiotic (ATB) use exists between neonatal intensive care units (NICUs) without demonstrated benefit to outcomes tested. Studies show that early-onset sepsis occurs in up to 2% of NICU patients, yet antibiotics (ABX) were started in over 50% of neonates admitted to our NICUs. An internal audit identified variations in prescribing practices and excessive use of ABX. As a result, we introduced ATB stewardship to our NICUs in 2015 to reduce unnecessary usage of these medications. Methods: We used standard quality improvement methodology utilizing multiple iterative plan-do-study-act cycles during a 6-year project to test various interventions aimed at using ABX wisely. Specifically, our goals were to reduce ABX on admission (AA), percent of patients who continued on ABX beyond 72 hours of life (AC), and ATB utilization rate in our 3 NICUs by 28% for each metric. Interventions implemented included the development of an ATB stewardship program consisting of a multidisciplinary team that met regularly, creation of tools and guidelines for evaluations of sepsis and ATB use, universal use of the neonatal early-onset sepsis calculator for all newborns 34 weeks and older gestational age, education regarding noninitiation of ABX for maternal indications in clinically well newborns, and discontinuation within 48 hours for asymptomatic newborns with negative blood cultures. Results: AA, AC, and ATB utilization rate decreased by 34.1%, 45.3%, and 34.9%, respectively, in our 3 NICUs. Conclusions: By introducing ATB stewardship in our NICUs, we exceeded our predetermined goal of significantly reducing ATB usage.

3.
Forensic Sci Int ; 336: 111317, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35504096

RESUMEN

The majority of fabrics at crime scenes have been coloured in some way. The effect of such treatments on resultant bloodstains has not been considered. In this work, horse blood was dropped onto reactively dyed calico fabrics (100% cotton, plain woven) with three different masses of 91 g m-², 171 g m-² and 243 g m-² and the results compared to previous work on the not-coloured calico fabric. Five impact velocities were used from 1.7 ms-1 to 5.4 ms-1. The use of reactive dye increased the thickness (from 0.38 - 0.56 mm to 0.39 - 0.6 mm) and mass per unit area (from 85.1 - 224.6 g/m² to 91 - 243 g/m²) of the calico fabrics. The reactively dyed fabrics had larger bloodstains (e.g. lightest calico 41.2 - 78.6 mm²) compares to the not-coloured fabrics (e.g. lightest calico 21.4 - 67.5 mm²) across all three mass per unit areas. The dyeing of the fabrics altered the intra-yarn spaces to a more optimum size for wicking blood, increasing the ease with which the blood could wick along the yarns in the dyed calico. The amount of wicking varied depending on individual variations within the fabrics and yarns. More variation in dry bloodstain area was seen among dyed calico specimens than for the not-coloured fabric. The amount of wicking which was seen on the dyed calico meant there was no correlation between dry bloodstain area and impact velocity, a correlation which was seen on the medium and heavy not-coloured calico in the previous work.


Asunto(s)
Manchas de Sangre , Colorantes , Animales , Acción Capilar , Caballos , Textiles
4.
Adv Neonatal Care ; 22(1): 6-14, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34334674

RESUMEN

BACKGROUND: Accurate diagnosis and timely management of neonatal late-onset sepsis (nLOS) have been less well-studied than those of early-onset sepsis. We noticed a delay in nLOS detection and management in our neonatal intensive care unit. PURPOSE: To develop an assessment tool to aid in the recognition and reporting of nLOS and to standardize the management process once sepsis is recognized. METHODS: The Plan-Do-Study-Act (PDSA) improvement model provided the framework for interventions for our antibiotic stewardship program, including the aims of this project. A literature review was performed to evaluate tools and other literature available to guide the evaluation and management of suspected sepsis. A quality improvement project was initiated to develop tools for the detection and management of nLOS. RESULTS: An nLOS assessment tool to help identify neonates at risk for nLOS and a Code Sepsis checklist to standardize the process of evaluation and management of nLOS were developed. The guiding principles of this tool development were empowerment of nurses to initiate the assessment process, clarification of team roles, and removal of barriers to appropriate antibiotic administration. IMPLICATIONS FOR PRACTICE: Useful and practical tools valued by nursing and the multidisciplinary team may facilitate timely identification and treatment of infants with nLOS. IMPLICATIONS FOR RESEARCH: Future directions include validation of the nLOS assessment tool and the Code Sepsis checklist as well as ensuring the reliability of the tool to improve detection of nLOS and to reduce time to administer antibiotics in cases of nLOS.


Asunto(s)
Programas de Optimización del Uso de los Antimicrobianos , Sepsis Neonatal , Sepsis , Antibacterianos/uso terapéutico , Lista de Verificación , Humanos , Lactante , Recién Nacido , Sepsis Neonatal/diagnóstico , Sepsis Neonatal/tratamiento farmacológico , Reproducibilidad de los Resultados , Sepsis/diagnóstico , Sepsis/tratamiento farmacológico
5.
Forensic Sci Int ; 301: 142-148, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31153991

RESUMEN

Using high speed video, the impact of blood drops falling at three velocities (1.9, 4.2 and 5.8ms-1) were filmed from both the technical face and for the first time the technical rear of three different mass per unit areas (85.1, 163.5 and 224.6g/m²) of 100% cotton calico. It was seen that there were two stages in the creation of a bloodstain on fabric; the impact dynamics, followed by wicking along the intra-yarn spaces. In the first stage, once the blood impacted the fabric, blood was visible on the technical rear of the fabrics with the medium and lightest mass per unit area within as little as 0.067ms after impact. No blood was visible on the technical rear of the fabric with the heaviest mass per unit area following impact or the medium mass per unit area from 1.7ms-1 impacts. On the technical face of the fabric, the blood drop spread laterally and then receded for 8ms following impact. The dynamics on the technical face were not affected by what was occurring on the technical rear of the fabric. The bloodstain on the technical rear initially only increased until 0.8ms following impact. The increase in technical rear bloodstain area was caused by continued movement of the blood through to the rear of the fabric as the blood drop spread on the technical face. Once the impact dynamics were concluded within 8ms of impact, there was no further change in the bloodstain for the remaining 67ms of high speed video. Following this the blood wicked into and along the yarns, resulting in a dry technical rear bloodstain on all fabrics at all velocities.


Asunto(s)
Manchas de Sangre , Textiles , Animales , Fenómenos Biofísicos , Acción Capilar , Medicina Legal/métodos , Hemorreología , Caballos , Grabación en Video
6.
Forensic Sci Int ; 301: 12-27, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31128405

RESUMEN

This paper discusses the effects of thickness, mass per unit area, sett, yarn linear density and twist of calico fabrics (100% cotton, plain woven) on the morphology of passive bloodstains. Horse blood was dropped vertically onto three calico fabrics with different mass per unit areas (85.1 g/m², 163.5 g/m² and 224.6 g/m²). Six different impact velocities were used (1.7 ms-1, 2.9 ms-1, 4.1 ms-1, 4.9 ms-1, 5.1 ms-1 and 5.4 ms-1). The dry bloodstains were largest on the calico with the lightest mass per unit area. The low yarn linear density and large inter-yarn spaces meant that the blood could wick into the yarns from all directions and along the intra-yarn spaces. The calico with the middle mass per unit area had the smallest mean dry bloodstain area for four out of the six velocities. The twist level for this calico was greater than for the calicos with a heavier or lighter mass per unit area. This reduced the amount of wicking which occurred along the yarns due to the tighter yarn structure. The calico with the heaviest mass per unit area had the highest yarn linear density resulting in a thicker fabric, so the blood could not as easily penetrate into the fabric. This resulted in a thicker wet blood layer remaining on the fabric surface, where it gradually wicked vertically into the yarns under gravity. Less wicking along the yarns occurred, resulting in a smaller bloodstain than on the fabric with the lightest mass per unit area. The correlation between impact velocity and mean dry bloodstain area was greater for the calicos with the medium and heaviest mass per unit area than for the calico with the lightest mass per unit area. For the calicos with the medium and heaviest mass per unit area, the distance the blood spread laterally at impact, which increased with the increase in impact velocity, had a greater influence on the dry bloodstain area than the amount of wicking.


Asunto(s)
Manchas de Sangre , Textiles , Animales , Acción Capilar , Ciencias Forenses/métodos , Caballos , Reología
7.
Int J Behav Med ; 25(1): 123-130, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28688094

RESUMEN

PURPOSE: This study sought to assess risk compensation following voluntary medical male circumcision of young school-going men. Risk compensation is defined as an inadvertent increase in sexual risk behaviors and a corresponding decrease in self-perceived risk for contracting HIV following the application of a risk reduction technology. METHODS: This study documented the sexual practices of circumcised (n = 485) and uncircumcised (n = 496) young men in 42 secondary schools at three time points (baseline and 6 and 12 months) in a sub-district of KwaZulu-Natal, South Africa. Study participants were aged from 16 to 24 years old. RESULTS: At the end of the study period, there was no significant difference between the two cohorts concerning learners' perceptions of being at risk of contracting HIV (interaction effect: b = -0.12, p = 0.40). There was also no significant difference in the number of sexual partners in the previous month (interaction effect: b = -0.23, p = 0.15). The proportion of learners who have never used a condom decreased significantly over time (time effect: b = -0.27, p = 0.01), and there was no difference between the circumcised and uncircumcised learners (interaction effect: b = -0.09, p = 0.91). CONCLUSIONS: Risk compensation, as evidenced in this study over a 1-year period, was not associated with undergoing voluntary medical male circumcision (VMMC) in our sample of young school-going men. However, it is of concern that at the end of this study, less than half of the sexually active sample in a high-HIV-prevalence community used condoms consistently in the previous month (39% for both study cohorts). The latter underscores the need to view VMMC as a potential entry point for planned HIV and sexuality education interventions targeting young men in this community.


Asunto(s)
Circuncisión Masculina/psicología , Infecciones por VIH/prevención & control , Conducta Sexual/psicología , Parejas Sexuales , Adolescente , Adulto , Circuncisión Masculina/estadística & datos numéricos , Condones/estadística & datos numéricos , Humanos , Masculino , Estudios Prospectivos , Asunción de Riesgos , Conducta Sexual/estadística & datos numéricos , Sudáfrica , Adulto Joven
8.
Aust Vet J ; 94(7): 232-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27349883

RESUMEN

OBJECTIVE: To determine the farm economic impact of bovine Johne's disease (BJD) infection and controls in commercial Victorian dairy herds. DESIGN: Benefit-cost analysis of BJD and various control methods in a Victorian dairy herd. RESULTS: Farm losses from BJD occurred from clinical disease. Clinical cases occur on average in 5-year-old cows, resulting in losses of A$1895 in the year of culling and A$221 in the year preceding culling, giving a total loss of A$2116. Early removal also resulted in loss of future profit equating to A$375 per year. This is the annualised value of foregone future income and costs expressed as a net present value (NPV). The total loss from removal of a clinical case was estimated as A$2491. The average clinical incidence in infected dairy herds prior to entry into the Victorian Bovine Johne's Test-and-Control Program (TCP) was 1.8% and the average Victorian dairy herd size was 262 cows in 2013-14, resulting in annual losses of 4.7 clinical cases if infected and implementing no BJD control. Farm annual loss of profit was estimated as A$11,748 ($44.84 per cow/year). Control of BJD using vaccination, test-and-cull or combined approaches was economical but the cost of implementation in initial years would exceed disease costs. Vaccination-based control provided minimal long-term losses and was the most cost-effective control over a 10-year planning horizon. CONCLUSION: Endemic BJD resulted in modest but persistent losses in typical infected dairy herds. Control of disease using test-and-cull, vaccination or combined test-and-cull with vaccination was cost-effective.


Asunto(s)
Enfermedades de los Bovinos/economía , Industria Lechera/economía , Paratuberculosis/economía , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Costos y Análisis de Costo/estadística & datos numéricos , Femenino , Paratuberculosis/epidemiología , Victoria/epidemiología
9.
Forensic Sci Int ; 257: 369-375, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26528668

RESUMEN

Very little is known about the interactions of blood and fabric and how bloodstains on fabric are formed. Whereas the blood stain size for non-absorbent surfaces depends on impact velocity, previous work has suggested that for fabrics the blood stain size is independent of impact velocity when the drop size is kept constant. Therefore, a greater understanding of the interaction of blood and fabric is required. This paper explores the possibility of using a micro computed tomography (CT) scanner to study bloodstain size and shape throughout fabrics. Two different fabrics were used: 100% cotton rib knit and 100% cotton bull drill. Bloodstains were created by dropping blood droplets from three heights; 500 mm, 1000 mm and 1500 mm. Results from the CT scanner clearly showed the bloodstain shape throughout the fabric. The blood was found to form a diamond shaped stain, with the maximum cross-sectional area 0.3-0.5mm below the surface. The bloodstain morphology depended on both the impact velocity and fabric structure.


Asunto(s)
Manchas de Sangre , Textiles , Microtomografía por Rayos X , Ciencias Forenses/métodos , Humanos , Procesamiento de Imagen Asistido por Computador
10.
J Forensic Leg Med ; 32: 77-83, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25882156

RESUMEN

Explosively propelled fragments are the most common cause of injury to UK service personnel in modern conflicts. Numerical injury models to simulate such injuries utilise algorithms based upon gelatin and animal tissue testing but data is limited on many fragment simulating projectiles and these simulants cannot represent human anatomy. Testing with post mortem specimens may overcome this limitation but no information exists about how post mortem tissue changes and storage conditions in humans or animals may affect projectile penetration. Two chisel nosed cylinders (0.49 g and 1.10 g) and a 0.51 g (5 mm) sphere were fired into three groups of porcine tissue (fresh, refrigerated and frozen then refrigerated) and compared to 20% gelatin. Depth of projectile penetration was ascertained with the assistance of computed tomography and kinetic energy absorption by tissues measured using Doppler radar and high speed photography. No difference in depth of penetration was found between porcine tissue stored in the different manners compared with 20% gelatin by impact velocities less than 100 m/s. Insufficient numbers of projectiles were retained in tissue at higher velocities for statistical analysis to be undertaken. Energy absorbed per millimetre of tissue ranged between 0.42 and 0.98 J/mm for different porcine tissue despite differing storage. This pilot study would suggest that the effect of refrigerating or freezing porcine tissue followed by thawing has no effect on its ability to retard these projectiles. Further research is required to ascertain if these results occur at greater velocities and for other types of projectile.


Asunto(s)
Balística Forense/métodos , Congelación , Modelos Biológicos , Refrigeración , Manejo de Especímenes/métodos , Animales , Porcinos
11.
J Mater Sci Mater Med ; 23(9): 2055-60, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22743865

RESUMEN

The kinetics of bone apatite crystallisation are examined using a novel approach to obtain quantitative, direction dependence features such as growth rate and activation energy. X-ray diffraction was employed for analysis of bovine, porcine and 'anorganic' bone specimens. Apatite coherence length was utilised as the independent variable within a Johnson-Mehl-Avrami (JMA) model. A direction averaged crystallisation activation energy of 183 ± 8 kJ mol(-1) was observed for the three bone groups. The Johnson-Mehl-Avrami 'n' exponent decreased with increasing temperature for all bone groups, indicating that apatite crystallisation changes to a diffusion limited process at higher temperatures. The results revealed little evidence to support any organic component 'protective' effect, and, on the contrary indicated that the organic matrix promotes apatite crystallisation.


Asunto(s)
Sustitutos de Huesos/síntesis química , Huesos/química , Calcificación Fisiológica/fisiología , Animales , Apatitas/química , Apatitas/farmacocinética , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacocinética , Huesos/metabolismo , Rastreo Diferencial de Calorimetría , Bovinos , Cementación/métodos , Cristalización , Cinética , Porcinos , Temperatura , Factores de Tiempo , Difracción de Rayos X
12.
Diabet Med ; 27(11): 1318-21, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20968113

RESUMEN

AIM: To examine the effects of chocolate on lipid profiles, weight and glycaemic control in individuals with Type 2 diabetes. METHODS: Twelve individuals with Type 2 diabetes on stable medication were enrolled in a randomized, placebo-controlled double-blind crossover study. Subjects were randomized to 45 g chocolate with or without a high polyphenol content for 8 weeks and then crossed over after a 4-week washout period. Changes in weight, glycaemic control, lipid profile and high-sensitivity C-reactive protein were measured at the beginning and at the end of each intervention. RESULTS: HDL cholesterol increased significantly with high polyphenol chocolate (1.16 ± 0.08 vs. 1.26 ± 0.08 mmol/l, P = 0.05) with a decrease in the total cholesterol: HDL ratio (4.4 ± 0.4 vs. 4.1 ± 0.4 mmol/l, P = 0.04). No changes were seen with the low polyphenol chocolate in any parameters. Over the course of 16 weeks of daily chocolate consumption neither weight nor glycaemic control altered from baseline. CONCLUSION: High polyphenol chocolate is effective in improving the atherosclerotic cholesterol profile in patients with diabetes by increasing HDL cholesterol and improving the cholesterol:HDL ratio without affecting weight, inflammatory markers, insulin resistance or glycaemic control.


Asunto(s)
Cacao/metabolismo , HDL-Colesterol/sangre , Diabetes Mellitus Tipo 2/metabolismo , Flavonoides/metabolismo , Fenoles/metabolismo , Adulto , Anciano , Glucemia/metabolismo , Proteína C-Reactiva/metabolismo , Dulces , Diabetes Mellitus Tipo 2/dietoterapia , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polifenoles
13.
J Psychopharmacol ; 22(3): 300-7, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18208905

RESUMEN

Neurotensin (NT) has been proposed as an endogenous antipsychotic based in part on the similarity in behavioural effects to antipsychotic drugs, for example, attenuation of both amphetamine-induced hyperlocomotion (AH) and amphetamine disrupted pre-pulse inhibition in the rat. However, there is some evidence that repeated administration of NT or an analogue produces behavioural tolerance to such effects. The present experiments sought to confirm and extend these findings by testing the effects on AH of 7 days central administration of NT and the NT1 selective analogue PD 149163 and the effects of 21 days central administration of NT. NT and PD149163 continuously administered for 7 days produced no effect on AH (in contrast to attenuation with a single injection here and previously reported), whereas 21 days of NT administration potentiated AH. Together, these studies report that the effects of NT or a NT analogue on AH depends on the duration of administration of peptide. The results are discussed in comparison with the reported antipsychotic properties of acute administration of NT and possible mechanisms involving NT1 receptors.


Asunto(s)
Anfetamina/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Actividad Motora/efectos de los fármacos , Neurotensina/análogos & derivados , Neurotensina/farmacología , Receptores de Neurotensina/agonistas , Animales , Barrera Hematoencefálica/efectos de los fármacos , Sinergismo Farmacológico , Inyecciones Intraventriculares , Masculino , Neurotensina/metabolismo , Radioinmunoensayo , Ratas
14.
J Food Sci ; 72(3): E138-42, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17995803

RESUMEN

Bubbles impart a very unique texture, chew, and mouth-feel to foods. However, little is known about the relationship between structure of such products and consumer response in terms of mouth-feel and eating experience. The objective of this article is to investigate the sensory properties of 4 types of bubble-containing chocolates, produced by using different gases: carbon dioxide, nitrogen, nitrous oxide, and argon. The structure of these chocolates were characterized in terms of (1) gas hold-up values determined by density measurements and (2) bubble size distribution which was measured by undertaking an image analysis of X-ray microtomograph sections. Bubble size distributions were obtained by measuring bubble volumes after reconstructing 3D images from the tomographic sections. A sensory study was undertaken by a nonexpert panel of 20 panelists and their responses were analyzed using qualitative descriptive analysis (QDA). The results show that chocolates made from the 4 gases could be divided into 2 groups on the basis of bubble volume and gas hold-up: the samples produced using carbon dioxide and nitrous oxide had a distinctly higher gas hold-up containing larger bubbles in comparison with those produced using argon and nitrogen. The sensory study also demonstrated that chocolates made with the latter were perceived to be harder, less aerated, slow to melt in the mouth, and having a higher overall flavor intensity. These products were further found to be creamier than the chocolates made by using carbon dioxide and nitrous oxide; the latter sample also showed a higher intensity of cocoa flavor.


Asunto(s)
Cacao/química , Cacao/normas , Comportamiento del Consumidor , Gases/química , Gusto , Argón/análisis , Argón/química , Dióxido de Carbono/análisis , Dióxido de Carbono/química , Fenómenos Químicos , Química Física , Gases/análisis , Humanos , Nitrógeno/análisis , Nitrógeno/química , Óxido Nitroso/análisis , Óxido Nitroso/química
15.
Pharmacol Biochem Behav ; 83(1): 114-21, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16451807

RESUMEN

In this study, we have used the selective A 2A adenosine receptor antagonist KW6002 to investigate the function of A 2A receptors in the Lister hooded rat nucleus accumbens in vitro and in vivo. Radioligand binding studies confirmed a greater than 50-fold selectivity of KW6002 for A 2A receptors compared to A1 receptors. Release of [3H]-dopamine from nucleus accumbens slices in vitro was almost doubled in the presence of 300 nM KW6002, while GABA release was inhibited by approximately one third. In vivo, intraperitoneal administration of KW6002 (4 mg kg(-1)) increased dopamine overflow almost 4-fold in the nucleus accumbens. In behavioural testing, KW6002 elicited place preference and increased locomotor activity at 1, 2 and 4 mg kg(-1). Taken together, these results suggest a role for tonic activation of A 2A adenosine receptors in reward-related phenomena.


Asunto(s)
Núcleo Accumbens/efectos de los fármacos , Purinas/farmacología , Receptor de Adenosina A2A/efectos de los fármacos , Animales , Unión Competitiva/efectos de los fármacos , Condicionamiento Operante/efectos de los fármacos , Dopamina/metabolismo , Relación Dosis-Respuesta a Droga , Espacio Extracelular/efectos de los fármacos , Espacio Extracelular/metabolismo , Técnicas In Vitro , Masculino , Microdiálisis , Actividad Motora/efectos de los fármacos , Núcleo Accumbens/metabolismo , Ratas , Receptor de Adenosina A2A/metabolismo , Triazinas/farmacología , Triazoles/farmacología , Xantinas/farmacología , Ácido gamma-Aminobutírico/metabolismo
16.
Neuroscience ; 138(4): 1309-17, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16426764

RESUMEN

Fear-conditioned analgesia is an important survival response which is expressed upon re-exposure to a context previously paired with a noxious stimulus. The aim of the present study was to characterize further the behavioral, monoaminergic and hypothalamo-pituitary-adrenal axis alterations associated with expression of fear-conditioned analgesia. Rats which had received footshock conditioning 24 h earlier, exhibited reduced formalin-evoked nociceptive behavior upon re-exposure to the footshock chamber, compared with non-footshocked formalin-treated rats. Intra-plantar injection of formalin reduced the duration of contextually-induced freezing and 20-40 kHz ultrasound emission. Intra-plantar injection of formalin to non-footshocked, non-conditioned rats did not induce ultrasonic vocalizations. Intra-plantar injection of formalin to footshock-conditioned rats, significantly increased tissue levels of 3,4-dihydroxyphenylacetic acid and the 3,4-dihydroxyphenylacetic acid:dopamine ratio in the periaqueductal gray and reduced levels of dopamine in the thalamus, compared with saline-treated footshocked controls. Non-footshocked, non-conditioned rats were capable of mounting a robust formalin-evoked increase in plasma corticosterone levels. Moreover, plasma corticosterone levels were significantly higher in saline-treated, footshock conditioned rats compared with saline-treated non-footshocked rats and levels did not differ between saline- and formalin-treated footshock conditioned rats. Assessment of the effects of the intra-plantar injection procedure revealed an attenuation of short-term extinction of contextually-induced freezing in rats anesthetized for intra-plantar injection of saline compared with non-anesthetized, non-injected rats as well as discrete effects on monoamines, their metabolites and plasma corticosterone levels. These data extend behavioral characterization of the phenomenon of fear-conditioned analgesia and suggest that measurement of ultrasound emission may be used as an ethologically relevant index of the defense response during fear-conditioned analgesia. Ultrasonic vocalization may also be a useful behavioral output to aid separation of nociception and aversion. The data provide evidence for discrete alterations in dopaminergic activity in the periaqueductal gray and thalamus and for altered hypothalamo-pituitary-adrenal axis activity following expression of defensive behavior.


Asunto(s)
Monoaminas Biogénicas/metabolismo , Miedo/fisiología , Sistema Hipotálamo-Hipofisario/metabolismo , Umbral del Dolor/fisiología , Dolor/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Analgesia , Animales , Conducta Animal/fisiología , Encéfalo/metabolismo , Condicionamiento Psicológico , Corticosterona/sangre , Modelos Animales de Enfermedad , Dopamina/metabolismo , Estimulación Eléctrica/efectos adversos , Masculino , Vías Nerviosas/metabolismo , Dolor/fisiopatología , Dimensión del Dolor/efectos de los fármacos , Umbral del Dolor/efectos de los fármacos , Ratas , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatología , Vocalización Animal/efectos de los fármacos , Vocalización Animal/fisiología
17.
Aust Vet J ; 83(12): 758-66, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16395942

RESUMEN

Preparedness for an incursion of an exotic animal disease is of key importance to government, industry, producers and the Australian community. An important aspect of Australia's preparedness for a possible incursion of foot-and-mouth disease is investigation into the likely effectiveness and cost-efficiency of eradication strategies when applied to different regional outbreak scenarios. Disease modelling is a tool that can be used to study diseases such as foot-and-mouth disease to better understand potential disease spread and control under different conditions. The Australian Government Department of Agriculture, Fisheries and Forestry has been involved with epidemiologic simulation modelling for more than 10 years, and has developed a sophisticated spatial model for foot-and-mouth disease (AusSpread) that operates within a geographic information system framework. The model accommodates real farm boundary or point-location data, as well as synthesised data based on agricultural census and land use information. The model also allows for interactions between herds or flocks of different animal species and production type, and considers the role that such interactions are likely to play in the epidemiology of a regional outbreak of foot-and-mouth disease. The user can choose mitigations and eradication strategies from those that are currently described in Australia's veterinary emergency plan. The model also allows the user to evaluate the impact of constraints on the availability of resources for mitigations or eradication measures. Outputs include a range of maps and tabulated outbreak statistics describing the geographic extent of the outbreak and its duration, the numbers of affected, slaughtered, and, as relevant, vaccinated herds or flocks, and the cost of control and eradication. Cost-related outputs are based on budgets of the value of stock and the cost of mitigations, each of which can be varied by the user. These outputs are a valuable resource to assist with policy development and disease management.


Asunto(s)
Simulación por Computador , Transmisión de Enfermedad Infecciosa/veterinaria , Fiebre Aftosa/transmisión , Modelos Biológicos , Animales , Australia/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/transmisión , Control de Enfermedades Transmisibles , Simulación por Computador/normas , Brotes de Enfermedades/prevención & control , Brotes de Enfermedades/estadística & datos numéricos , Brotes de Enfermedades/veterinaria , Fiebre Aftosa/epidemiología , Enfermedades de las Cabras/epidemiología , Enfermedades de las Cabras/prevención & control , Enfermedades de las Cabras/transmisión , Cabras , Ovinos , Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/prevención & control , Enfermedades de las Ovejas/transmisión , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/prevención & control , Enfermedades de los Porcinos/transmisión , Vacunación/veterinaria
18.
Eur J Neurosci ; 20(3): 848-52, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15255996

RESUMEN

Fear-conditioned analgesia is an important survival response mediated by substrates controlling nociception and aversion. Cannabinoid(1) (CB(1)) receptors play an important role in nociception and aversion. However, their role in fear-conditioned analgesia has not been investigated. This study investigated the effects of systemic administration of the CB(1) receptor antagonist, SR141716A (1 mg/kg, i.p.), on fear-conditioned analgesia and conditioned aversion in rats. Twenty-four hours after receiving footshock, rats exhibited reduced formalin-evoked nociceptive behaviour, increased freezing and increased defecation when tested in the footshock apparatus, compared with non-footshocked formalin-injected rats. SR141716A attenuated fear-conditioned analgesia, freezing and defecation. Importantly, SR141716A had no effect on formalin-evoked nociceptive behaviour over an equivalent time period in rats not receiving footshock. SR141716A had no effect on contextually induced freezing during the first half of the test trial in rats receiving intra-plantar injection of saline. Administration of SR1417176A did, however, attenuate short-term extinction of contextually induced freezing and ultrasound emission in rats receiving intra-plantar saline, compared with vehicle-treated saline controls. These data suggest an important role for the CB(1) receptor in mediating fear-conditioned analgesia and provide evidence for differential modulation of conditioned aversive behaviour by CB(1) receptors during tonic, persistent pain.


Asunto(s)
Analgesia , Reacción de Prevención/fisiología , Condicionamiento Psicológico/fisiología , Miedo/fisiología , Receptor Cannabinoide CB1/fisiología , Análisis de Varianza , Animales , Reacción de Prevención/efectos de los fármacos , Conducta Animal , Condicionamiento Psicológico/efectos de los fármacos , Masculino , Actividad Motora/efectos de los fármacos , Dimensión del Dolor/efectos de los fármacos , Piperidinas/farmacología , Pirazoles/farmacología , Ratas , Receptor Cannabinoide CB1/antagonistas & inhibidores , Rimonabant , Factores de Tiempo
19.
Eur J Neurosci ; 19(3): 678-86, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14984418

RESUMEN

The antinociceptive effects of Delta9-tetrahydrocannabinol (Delta9-THC) have been widely described; however, its therapeutic potential may be limited by secondary effects. We investigated whether coadministration of low doses of cannabinoids or cannabinoids and morphine produced antinociception in the absence of side-effects. Effects of preadministration (i.p.) of Delta9-THC (1 or 2.5 mg/kg), cannabidiol (5 mg/kg), morphine (2 mg/kg), Delta9-THC + morphine, Delta9-THC + cannabidiol or vehicle on formalin-evoked nociceptive behaviour were studied over 60 min. Trunk blood and brains were collected 60 min after formalin injection and assayed for corticosterone and tissue levels of monoamines and metabolites, respectively. Drug effects on locomotor activity, core body temperature and grooming were assessed. Delta9-THC reduced both phases of formalin-evoked nociceptive behaviour, enhanced the formalin-evoked corticosterone response and increased the 4-hydroxy-3-methoxyphenylglycol : noradrenaline ratio in the hypothalamus. Cannabidiol alone had no effect on these indices and did not modulate the effects of Delta9-THC. Morphine reduced both phases of formalin-evoked nociceptive behaviour. Coadministration of Delta9-THC and morphine reduced the second phase of formalin-evoked nociceptive behaviour to a greater extent than either drug alone, and increased levels of thalamic 5-hydroxytryptamine. While the antinociceptive effects of Delta9-THC and morphine alone occurred at doses devoid of effects on locomotor activity, coadministration of Delta9-THC and morphine inhibited locomotor activity. In conclusion, coadministration of a low dose of morphine, but not cannabidiol, with Delta9-THC, increased antinociception and 5-hydroxytryptamine levels in the thalamus in a model of persistent nociception. Nevertheless, these enhanced antinociceptive effects were associated with increased secondary effects on locomotor activity.


Asunto(s)
Monoaminas Biogénicas/metabolismo , Dronabinol/uso terapéutico , Morfina/uso terapéutico , Narcóticos/uso terapéutico , Dolor/tratamiento farmacológico , Animales , Conducta Animal/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Encéfalo/anatomía & histología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Química Encefálica , Cannabidiol/uso terapéutico , Cromatografía Líquida de Alta Presión , Corticosterona/sangre , Modelos Animales de Enfermedad , Interacciones Farmacológicas , Formaldehído , Masculino , Actividad Motora/efectos de los fármacos , Dolor/inducido químicamente , Dolor/fisiopatología , Dimensión del Dolor , Psicotrópicos/uso terapéutico , Radioinmunoensayo , Ratas , Factores de Tiempo
20.
Br J Pharmacol ; 141(2): 253-62, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14707029

RESUMEN

1. The ability of the endogenous fatty acid amide, cis-oleamide (ODA), to bind to and activate cannabinoid CB(1) and CB(2) receptors was investigated. 2. ODA competitively inhibited binding of the nonselective cannabinoid agonist [(3)H]CP55,940 and the selective CB(1) antagonist [(3)H]SR141716A to rat whole-brain membranes with K(i) values of 1.14 microm (0.52-2.53 microm, Hill slope=0.80, n=6) and 2.63 microm (0.62-11.20 microm, Hill slope=0.92, n=4), respectively. AEA inhibited [(3)H]CP55,940 binding in rat whole-brain membranes with a K(i) of 428 nm (346-510 nm, Hill slope=-1.33, n=3). 3. ODA competitively inhibited [(3)H]CP55,940 binding in human CB(1) (hCB(1)) cell membranes with a K(i) value of 8.13 microm (4.97-13.32 microm, n=2). In human CB(2) transfected (hCB(2)) HEK-293T cell membranes, 100 microm ODA produced only a partial (42.5+/-7%) inhibition of [(3)H]CP55,940 binding. 4. ODA stimulated [(35)S]GTPgammaS binding in a concentration-dependent manner (EC(50)=1.64 microm (0.29-9.32 microm), R(2)=0.99, n=4-9), with maximal stimulation of 188+/-9% of basal at 100 microm. AEA stimulated [(35)S]GTPgammaS binding with an EC(50) of 10.43 microm (4.45-24.42 microm, R(2)=1.00, n=3, 195+/-4% of basal at 300 microm). Trans-oleamide (trans-ODA) failed to significantly stimulate [(35)S]GTPgammaS binding at concentrations up to 100 microm. 5. ODA (10 microm)-stimulated [(35)S]GTPgammaS binding was reversed by the selective CB(1) antagonist SR141716A (IC(50)=2.11 nm (0.32-13.77 nm), R(2)=1.00, n=6). 6. The anatomical distribution of ODA-stimulated [(35)S]GTPgammaS binding in rat brain sections was indistinguishable from that of HU210. Increases of similar magnitude were observed due to both agonists in the striatum, cortex, hippocampus and cerebellum. 7. ODA (10 microm) significantly inhibited forskolin-stimulated cyclic AMP (cAMP) accumulation in mouse neuroblastoma N1E 115 cells (P=0.02, n=11). ODA-mediated inhibition was completely reversed by 1 microm SR141716A (P<0.001, n=11) and was also reversed by pretreatment with 300 ng ml(-1) pertussis toxin (P<0.001, n=6). 8. These data demonstrate that ODA is a full cannabinoid CB(1) receptor agonist. Therefore, in addition to allosteric modulation of other receptors and possible entourage effects due to fatty acid amide hydrolase inhibition, the effects of ODA may be mediated directly via the CB(1) receptor.


Asunto(s)
Moduladores de Receptores de Cannabinoides/metabolismo , Ácidos Oléicos/metabolismo , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/metabolismo , Animales , Moduladores de Receptores de Cannabinoides/farmacología , Línea Celular , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Humanos , Ratones , Ácidos Oléicos/farmacología , Unión Proteica/efectos de los fármacos , Unión Proteica/fisiología , Ratas
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