RESUMEN
A correctly positioned vehicle head restraint (HR) can reduce whiplash injury risk in collisions, however, HRs are often sub-optimally positioned. The primary aim of this study was to investigate vehicle HR position and driver knowledge of correct HR positioning in an Irish population. Secondary aims were to investigate the associations with driver age, gender and vehicle age. Data collection involved HR measurement and a driver questionnaire (n = 110). Just 27% of drivers had optimal HR positioning, while 30% had poor or marginal positioning. Newer vehicles (<5 years old) had better positioned HR in the horizontal plane (p = 0.036), than older vehicles. Younger drivers (<30 years) were more likely to have poorer positioning of HR (p = 0.002), than the 30 years or over group. Females were more likely to have better vertical positioning of their HR (p = 0.003) than males. Driver knowledge of correct position was variable, and not associated with actual HR position, with 65% knowing the correct vertical positioning standard but only 27% identifying the correct horizontal position. Many drivers have inadequately positioned HR, which needs to be addressed by improved vehicle design and public education.
Asunto(s)
Conducción de Automóvil , Dispositivos de Protección de la Cabeza , Conocimientos, Actitudes y Práctica en Salud , Lesiones por Latigazo Cervical/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Primary gastrointestinal cytomegalovirus (CMV) disease after solid organ transplantation (SOT) is difficult to treat and may relapse. Herein, we reviewed the clinical records of CMV D+/R- SOT recipients with biopsy-proven gastrointestinal CMV disease to determine predictors of relapse. The population consisted of 26 kidney (13 [50%]), liver (10 [38%]) and heart (3 [12%]) transplant recipients who developed gastrointestinal CMV disease at a median of 54 (interquartile range [IQR]: 40-70) days after stopping antiviral prophylaxis. Except for one patient, all received induction intravenous ganciclovir (mean+/-SD, 33.8+/-19.3 days) followed by valganciclovir (27.5+/-13.3 days) in 18 patients. Ten patients further received valganciclovir maintenance therapy (41.6+/-28.6 days). The median times to CMV PCR negativity in blood was 22.5 days (IQR: 16.5-30.7) and to normal endoscopic findings was 27.0 days (IQR: 21.0-33.5). CMV relapse, which occurred in seven (27%) patients, was significantly associated with extensive disease (p=0.03). CMV seroconversion, viral load, treatment duration, maintenance therapy and endoscopic findings at the end of therapy were not significantly associated with CMV relapse. In conclusion, an extensive involvement of the gastrointestinal tract was significantly associated with CMV relapse. However, endoscopic evidence of resolution of gastrointestinal disease did not necessarily translate into a lower risk of CMV relapse.
Asunto(s)
Antivirales/uso terapéutico , Infecciones por Citomegalovirus/tratamiento farmacológico , Infecciones por Citomegalovirus/etiología , Enfermedades Gastrointestinales/tratamiento farmacológico , Enfermedades Gastrointestinales/etiología , Trasplantes/efectos adversos , Trasplantes/virología , Adulto , Estudios de Cohortes , Citomegalovirus/genética , Citomegalovirus/aislamiento & purificación , Infecciones por Citomegalovirus/transmisión , Infecciones por Citomegalovirus/virología , Femenino , Ganciclovir/análogos & derivados , Ganciclovir/uso terapéutico , Enfermedades Gastrointestinales/virología , Trasplante de Corazón/efectos adversos , Humanos , Trasplante de Riñón/efectos adversos , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Pronóstico , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Valganciclovir , Carga Viral/efectos de los fármacos , Viremia/tratamiento farmacológico , Viremia/etiología , Viremia/virologíaRESUMEN
(E,Z) -2,4-decadienoate (pear ester) is a larval kairomone for the codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae). Orchard studies were conducted in 2005 and 2006 in apple, Malus domestica Borkhausen, and pear, Pyrus communis L., to evaluate a 5% active ingredient (AI), microencapsulated formulation of pear ester (PE-MEC) as an insecticidal additive for the codling moth granulovirus (CpGV). Although CpGV applied at 5-15-d intervals at commercial rates (2.2 X 10(12)-10(13) granules per ha) killed the majority (82-94%) of larvae found inside infested fruit, it did not eliminate significant damage, i.e., 30-92% fruit injury at harvest versus 51-82% in controls. PE-MEC treatments had significant but inconsistent results in our tests. In apple (mixed cultivars), PE-MEC (3.7-4.7 g [AI] /ha) plus CpGV reduced the percentage of fruit injured during the second but not the first larval generation, compared with CpGV alone, but there no was no additional population reduction (live larvae collected from infested fruit and tree bands). In 'Bartlett' pear, PE-MEC (3.7 g [AI] /ha) plus CpGV significantly increased larval mortality and reduced deep fruit entries at harvest over CpGV alone in 2006, but similar improvements were not observed in 2005 when a lower rate (1.5 g [AI] /ha) was tested. Surprisingly, compared with untreated controls, the PE-MEC formulation alone also reduced fruit injury (mid-season in Bartlett) and larval survivorship inside infested fruit at harvest (2006 apple tests and both years in Bartlett). Although pear ester seems amenable as a kairomonal adjuvant for use with insecticides, our inconsistent data with CpGV in apple and pear suggest practical improvements in formulation and application strategies (e.g., to optimize and maintain attractive release rates) are needed.
Asunto(s)
Decanoatos/farmacología , Granulovirus/fisiología , Mariposas Nocturnas/efectos de los fármacos , Control Biológico de Vectores , Feromonas/farmacología , Pyrus/química , Animales , Decanoatos/aislamiento & purificación , Conducta Alimentaria/efectos de los fármacos , Malus/parasitología , Mariposas Nocturnas/fisiología , Mariposas Nocturnas/virología , Feromonas/aislamiento & purificación , Pyrus/parasitologíaRESUMEN
Commercial formulations of the codling moth, Cydia pomonella L., granulovirus (CpGV) are limited by their short residual activity under orchard conditions in the Pacific Northwest. We evaluated spray-dried lignin-encapsulated formulations of CpGV for improved solar stability based on laboratory bioassays with a solar simulator and in field tests in an infested apple orchard. In laboratory tests, aqueous lignin formulations containing a high dosage of 3 x 10(10) occlusion bodies (OB)/L, with and without the additives titanium dioxide (TiO(2)) and sugar, provided significant solar protection of virus, i.e., mortality of codling moth exposed to lignin formulations that had been irradiated with 9.36 x 10(6) joules/m(2) was 92-94%, compared with 66-67% from a glycerin-stabilized product (Cyd-X) or suspension of pure unformulated virus at the same rates. By comparison, a lower dosage of the lignin formulation (3 x 10(8)OB/L) did not provide significant solar protection. Equivalent dosage-dependent patterns in solar protection were observed in further tests with the lignin formulation, when an intermediate (3 x 10(9)OB/L) as well as the low dosage provided no solar protection. Equivalent rates of a blank lignin formulation (containing no virus) did not affect larval mortality, suggesting a protective effect of the lignin on the virus at the high rate. The use of several spray adjuvants, 'NuFilm-17' and 'Organic Biolink' (sticker-spreaders at 0.06% v/v), 'Raynox' (sunburn protectant at 5% v/v), and 'Trilogy'(neem oil at 1% v/v) did not provide solar protection of a commercial CpGV preparation in laboratory tests. In season long orchard tests (Golden Delicious), the lignin formulation of CpGV applied at 6.57 x 10(12)OB/ha did not significantly improve control of codling moth or protection of fruit compared with Cyd-X at equivalent rates. Our studies show that lignin-based CpGV formulations provided solar protection at relatively high virus dosages. The testing of lignin formulations containing reduced virus concentrations may allow virus solar protection to be achieved at more economical rates.
Asunto(s)
Composición de Medicamentos/métodos , Granulovirus/patogenicidad , Granulovirus/efectos de la radiación , Mariposas Nocturnas/virología , Rayos Ultravioleta/efectos adversos , Animales , Carbohidratos , Susceptibilidad a Enfermedades/virología , Frutas , Control de Insectos/métodos , Lignina , Mariposas Nocturnas/patogenicidad , Noroeste de Estados Unidos , Plaguicidas/toxicidad , Protección Radiológica/métodos , TitanioRESUMEN
New formulations of the codling moth, Cydia pomonella (L.), granulovirus (CpGV) [family Baculoviridae, genus Granulovirus] are commercially available in North America. In field tests on apple (Malus sp. 'Delicious'), we compared different application strategies for CpGV (Cyd-X, Certis USA, Clovis, CA) used in full-season programs against high pest populations. In replicated single tree plots, three rates (0.073, 0.219, and 0.438 liter ha(-1)) and application intervals (7, 10, and 14 d) killed 81-99% of larvae in fruit and reduced the number of mature larvae recovered in tree bands by 54-98%. Although the proportion of deep entries declined by 77-98%, the amount of fruit injury was not reduced compared with controls. There was a statistical trend between increasing dosage and spray frequency intervals and virus effectiveness, but no interaction between these factors. In a commercial orchard, we assessed a standard (0.219 liter ha(-1)) and two reduced rates of the virus (0.146 and 0.073 liter ha(-1)) applied in a weekly spray program in replicated 0.2-ha blocks. In the first generation, fruit injury was reduced in virus-treated compared with three untreated blocks although the decrease was only significant at the standard rate. Mortality rates of larvae (in fruit) were > or =90%, dose dependent, and comparable with rates observed from individual trees sprayed with equivalent treatments in the previous study. Rates of larval mortality declined at all dosages (81-85%) in the first part of the second generation. Most damage and proportionally less mortality occurred in the upper canopy. High pest pressures and untreated blocks contributed to significant damage and the study was terminated early. These data suggest virus programs can be tailored according to the localized pest pressure, but it may not prevent economic damage in high-pressure situations.
Asunto(s)
Granulovirus/fisiología , Control de Insectos/métodos , Larva/virología , Malus/crecimiento & desarrollo , Mariposas Nocturnas/virología , Animales , Mariposas Nocturnas/crecimiento & desarrollo , Control Biológico de VectoresRESUMEN
Applications of entomopathogenic nematodes in the families Steinernematidae and Heterorhabditidae have traditionally been targeted against soil insects. Nonetheless, research over the last two decades highlights the potential of such agents against above-ground pests under certain circumstances. A general linear model was used to test for patterns in efficacy among 136 published trials with Steinernema carpocapsae Weiser, the most common species applied against foliar and other above-ground pests. The focus was on field and greenhouse assessments, rather than laboratory assays where relevant ecological barriers to infection are typically removed. The model showed differences in nematode treatment efficacy depending on the pests' target habitat (bore holes > cryptic foliage > exposed foliage) and trial location (greenhouse > field studies). Relative humidity and temperature during and up to 8 h post-application were also predicted to influence rates of nematode infection obtained. Conversely, spray adjuvants (both wetting agents and anti-desiccants) and nematode dosage applied (both concentration and use of consecutive applications 3-4 days apart) did not explain a significant amount of variance in nematode performance. With reference to case studies the model is used to discuss the relative importance of different factors on nematode efficacy and highlight priorities for workers considering using entomopathogenic nematodes to target pests in novel environments.
Asunto(s)
Agricultura/métodos , Insectos/crecimiento & desarrollo , Nematodos/fisiología , Control Biológico de Vectores , Suelo/parasitología , Animales , Humedad , Modelos Lineales , TemperaturaRESUMEN
Computer simulations using the simplified energy function and simulated tempering dynamics have accurately determined the native structure of the pYVPML, SVLpYTAVQPNE, and SPGEpYVNIEF peptides in the complexes with SH2 domains. Structural and equilibrium aspects of the peptide binding with SH2 domains have been studied by generating temperature-dependent binding free energy landscapes. Once some native peptide-SH2 domain contacts are constrained, the underlying binding free energy profile has the funnel-like shape that leads to a rapid and consistent acquisition of the native structure. The dominant native topology of the peptide-SH2 domain complexes represents an extended peptide conformation with strong specific interactions in the phosphotyrosine pocket and hydrophobic interactions of the peptide residues C-terminal to the pTyr group. The topological features of the peptide-protein interface are primarily determined by the thermodynamically stable phosphotyrosyl group. A diversity of structurally different binding orientations has been observed for the amino-terminal residues to the phosphotyrosine. The dominant native topology for the peptide residues carboxy-terminal to the phosphotyrosine is tolerant to flexibility in this region of the peptide-SH2 domain interface observed in equilibrium simulations. The energy landscape analysis has revealed a broad, entropically favorable topology of the native binding mode for the bound peptides, which is robust to structural perturbations. This could provide an additional positive mechanism underlying tolerance of the SH2 domains to hydrophobic conservative substitutions in the peptide specificity region.
Asunto(s)
Modelos Moleculares , Péptidos/química , Péptidos/metabolismo , Dominios Homologos src , Sitios de Unión , Simulación por Computador , Interacciones Hidrofóbicas e Hidrofílicas , Ligandos , Método de Montecarlo , Unión Proteica , Temperatura , TermodinámicaRESUMEN
The effects of relative humidity (RH) and temperature on the sporulation of Metarhizium anisopliae var. acridum on mycosed cadavers of desert locust, Schistocerca gregaria, were assessed in the laboratory. Quantitative assessments of conidial production over 10 days under constant conditions showed that sporulation was optimized at RH > 96% and at temperatures between 20 and 30 degrees C. Under both these conditions >10(9) conidia/cadaver were produced. At 25 degrees C, conidial yield was maximized under conditions in which cadavers remained in contact with damp substrate. Relatively little sporulation occurred at 15 degrees C (< 3 x 10(7) conidia/cadaver) and 40 degrees C (< 4 x 10(6) conidia/cadaver) and no sporulation occurred at 10 or 45 degrees C. Following incubation, conidial yield was closely related to the water content of locust cadavers. In separate tests, locust cadavers were incubated for 10 days under diurnally fluctuating temperature and RH that comprised favorable (25 degrees C/100% RH) alternating with unfavorable (40 degrees C/80% RH) conditions for sporulation. In this case, fewer conidia were produced compared with cadavers that were incubated under the favorable conditions for an equal period cumulatively but were not periodically exposed to unfavorable conditions. However, this reduced sporulation observed with the fluctuating condition was not observed when cadavers were similarly incubated under favorable/unfavorable conditions of temperature but were not periodically exposed to the low RH condition. This result implies that sporulation is a dynamic process, dependent not only on periodic exposure to favorable RH but also on the interrelation of this with low RH. Associated tests and the monitoring of changes in cadaver weights imply that the mechanism driving the reduced sporulation under fluctuating RH is the net water balance of cadavers, i.e. the cumulative ability of the fungus/cadaver to adsorb water necessary for sporulation at high RH is restricted by water loss associated with intermittent exposure to a low RH. The duration of daily exposure to high humidity appears to be a crucial constraint to the recycling ability of M. anisopliae var. acridum.
Asunto(s)
Saltamontes/microbiología , Humedad , Hongos Mitospóricos/fisiología , Micosis/microbiología , Esporas Fúngicas/fisiología , Temperatura , Animales , Cadáver , Femenino , MasculinoRESUMEN
Common failures in predicting crystal structures of ligand-protein complexes are investigated for three ligand-protein systems by a combined thermodynamic and kinetic analysis of the binding energy landscapes. Misdocked predictions in ligand-protein docking are classified as 'soft' and 'hard' failures. While a soft failure arises when the search algorithm is unable to find the global energy minimum corresponding to the crystal structure, a hard failure results from a flaw of the energy function to qualify the crystal structure as the predicted lowest energy conformation in docking simulations. We find that neither the determination of a single structure with the lowest energy nor finding the most common binding mode is sufficient to predict crystal structures of the complexes, which belong to the category of hard failures. In a proposed hierarchical approach, structural similarity clustering of the conformations, generated from equilibrium simulations with the simplified energy function, is followed by energy refinement with the AMBER force field. This protocol, that involves a hierarchy of energy functions, resolves some common failures in ligand-protein docking and detects crystallographic binding modes that were not found during docking simulations.
Asunto(s)
Proteínas/metabolismo , Cristalografía , Glucosiltransferasas/química , Glucosiltransferasas/metabolismo , Cinética , Ligandos , Maltosa/química , Maltosa/metabolismo , Modelos Moleculares , Estructura Molecular , Proteínas/química , TermodinámicaRESUMEN
The thermodynamic and kinetic aspects of molecular recognition for the methotrexate (MTX)-dihydrofolate reductase (DHFR) ligand-protein system are investigated by the binding energy landscape approach. The impact of 'hot' and 'cold' errors in ligand mutations on the thermodynamic stability of the native MTX-DHFR complex is analyzed, and relationships between the molecular recognition mechanism and the degree of ligand optimization are discussed. The nature and relative stability of intermediates and thermodynamic phases on the ligand-protein association pathway are studied, providing new insights into connections between protein folding and molecular recognition mechanisms, and cooperativity of ligand-protein binding. The results of kinetic docking simulations are rationalized based on the thermodynamic properties determined from equilibrium simulations and the shape of the underlying binding energy landscape. We show how evolutionary ligand selection for a receptor active site can produce well-optimized ligand-protein systems such as MTX-DHFR complex with the thermodynamically stable native structure and a direct transition mechanism of binding from unbound conformations to the unique native structure.
Asunto(s)
Simulación por Computador , Modelos Moleculares , Unión Proteica , Animales , Sitios de Unión , Evolución Molecular , Antagonistas del Ácido Fólico/química , Antagonistas del Ácido Fólico/metabolismo , Antagonistas del Ácido Fólico/farmacología , Ligandos , Sustancias Macromoleculares , Metotrexato/química , Metotrexato/metabolismo , Metotrexato/farmacología , Modelos Químicos , Método de Montecarlo , Conformación Proteica , Pliegue de Proteína , Selección Genética , Relación Estructura-Actividad , Tetrahidrofolato Deshidrogenasa/química , Tetrahidrofolato Deshidrogenasa/metabolismo , TermodinámicaRESUMEN
PURPOSE: To demonstrate the technique and feasibility of prostate brachytherapy performed with local anesthesia only. METHODS AND MATERIALS: A 5 by 5 cm patch of perineal skin and subcutaneous tissue is anesthetized by local infiltration of 10 cc of 1% lidocaine with epinephrine, using a 25-gauge 5/8-inch needle. Immediately following injection into the subcutaneous tissues, the deeper tissues, including the pelvic floor and prostate apex, are anesthetized by injecting 15 cc lidocaine solution with approximately 8 passes of a 20-gauge 1.0-inch needle. Following subcutaneous and peri-apical lidocaine injections, the patient is brought to the simulator suite and placed in leg stirrups. The transrectal ultrasound (TRUS) probe is positioned to reproduce the planning images and a 3.5- or 6.0-inch, 22-gauge spinal needle is inserted into the peripheral planned needle tracks, monitored by TRUS. When the tips of the needles reach the prostatic base, about 1 cc of lidocaine solution is injected in the intraprostatic track, as the needle is slowly withdrawn, for a total volume of 15 cc. The implants are done with a Mick Applicator, inserting and loading groups of two to four needles, so that a maximum of only about four needles are in the patient at any one time. During the implant procedure, an additional 1 cc of lidocaine solution is injected into one or more needle tracks if the patient experiences substantial discomfort. The total dose of lidocaine is generally limited to 500 mg (50 ml of 1% solution). RESULTS: To date, we have implanted approximately 50 patients in our simulator suite, using local anesthesia. Patients' heart rate and diastolic blood pressure usually showed moderate changes, consistent with some discomfort. The time from first subcutaneous injection and completion of the source insertion ranged from 35 to 90 minutes. Serum lidocaine levels were below or at the low range of therapeutic. There has been only one instance of acute urinary retention in the patients treated so far, and no unplanned admissions to the hospital or need to reschedule a patient to be implanted under general or spinal anesthesia. CONCLUSIONS: The substitution of local anesthesia has facilitated rapid introduction of a high-volume brachytherapy program at an institution that previously had none, without requiring the allocation of significant operating room time. Although the patients reported here were implanted without conscious sedation, we are starting to try various sedatives and analgesics for patients who we anticipate will have substantial anxiety with the procedure.
Asunto(s)
Anestesia Local/métodos , Anestésicos Locales , Braquiterapia/métodos , Lidocaína , Neoplasias de la Próstata/radioterapia , Agonistas Adrenérgicos , Anestésicos Locales/administración & dosificación , Anestésicos Locales/efectos adversos , Epinefrina , Estudios de Factibilidad , Humanos , Lidocaína/administración & dosificación , Lidocaína/efectos adversos , Masculino , Factores de TiempoRESUMEN
The thermodynamics of ligand-protein molecular recognition is investigated by the energy landscape approach for two systems: methotrexate(MTX)--dihydrofolate reductase(DHFR) and biotin-streptavidin. The temperature-dependent binding free energy profile is determined using the weighted histogram analysis method. Two different force fields are employed in this study: a simplified model of ligand-protein interactions and the AMBER force field with a soft core smoothing component, used to soften the repulsive part of the potential. The results of multiple docking simulations are rationalized from the shape of the binding free energy profile that characterizes the thermodynamics of the binding process.
Asunto(s)
Simulación por Computador , Modelos Químicos , Proteínas/química , Proteínas/metabolismo , Programas Informáticos , Biotina/química , Biotina/metabolismo , Cinética , Ligandos , Metotrexato/química , Metotrexato/metabolismo , Método de Montecarlo , Unión Proteica , Estreptavidina/química , Estreptavidina/metabolismo , Temperatura , Tetrahidrofolato Deshidrogenasa/química , Tetrahidrofolato Deshidrogenasa/metabolismo , TermodinámicaRESUMEN
A prototype laser-fiber optic based sensor for in situ monitoring of nicotinamide adenine dinucleotide (NADH) has been developed. This system is based on a compact neodymium-yttrium-aluminum-garnet (Nd:YAG) laser with associated harmonic generators. Light distribution to and from tissue is handled by a fiber optic network, including a long optical fiber to be inserted into the target tissue. Immobilizing the enzyme lactate dehydrogenase on the fiber tip converts the monitoring channel into a lactate sensor. A new dual beam reflection approach for blood volume artifact compensation is tested. Detection sensitivity of free NADH in the micromolar region is achieved. The method and system configuration appear feasible for continuous in situ monitoring of two important indices of ischemia and hypoxia in a clinical setting.