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1.
Artículo en Inglés | MEDLINE | ID: mdl-38597199

RESUMEN

STUDY DESIGN: Retrospective study. OBJECTIVE: To explore the association between patients undergoing lumbar spine surgery who message their care team via an electronic patient portal (EPP) post-operatively and emergency department (ED) visits within 90 days of surgery. SUMMARY OF BACKGROUND DATA: Secure patient messaging through electronic patient portals has grown over recent years. Despite its frequent utilization by patients to engage with their care team, its association with clinical outcomes remains unknown in spine surgery. METHODS: This study was approved by our Institutional Review Board. Inclusion criteria were adults who underwent single-stage lumbar spine surgery between January 2016-June 2023. Patients with incomplete information, multi-stage surgeries, and those who died within 90 days of surgery were excluded. Patient sociodemographic, surgical, hospital readmission, and patient-provider engagement data were collected. RESULTS: A total of 13,135 patients were included. A total of 1,711 patients (13%) had a post-operative ED visit, and 4,791 patients (36%) used the patient portal to send a message after surgery. Sending a post-operative patient message after undergoing lumbar spine surgery was associated with an increased likelihood of having an ED visit that does not lead to readmission (1.29 (1.10-1.53), P = 0.002). Patients with high school degrees were more likely to have an ED visit without readmission (1.33 (1.08-1.65), P = 0.008). CONCLUSION: Patients at a higher risk of presenting to the ED post-operatively should be identified and may benefit from additional counseling and access to the care team virtually to limit unnecessary healthcare utilization. Focusing on patients who reach out via EPP messaging post-operatively may be a good target patient group to address first. Future research is needed to investigate the possible health literacy and other socioeconomic barriers affecting these patients so that appropriate, more cost-effective resources can be utilized to avoid clinically unnecessary and costly ED visits.

2.
Pharmeur Bio Sci Notes ; 2024: 1-11, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38533744

RESUMEN

This publication describes the outcome of a project to develop a replacement European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) for Human tetanus immunoglobulin (TIg) as well as for the World Health Organization (WHO) International Standard (IS) for Tetanus Immunoglobulin, Human. Bulk TIg was kindly provided by a European manufacturer and was used to prepare the candidate standard. The candidate standard was freeze-dried and calibrated in an international collaborative study jointly co-ordinated by the Medicines & Healthcare products Regulatory Agency (MHRA) and the European Directorate for the Quality of Medicines & HealthCare (EDQM, Council of Europe). The results of this study show that there was good agreement between laboratories for the potency estimates obtained for the candidate standard relative to the current WHO IS/Ph. Eur. BRP. The study also demonstrated that the candidate standard is suitable for use in Ph. Eur. assays for potency testing of TIg products and there was good agreement in the potency estimates obtained using the different assay methods included in the study. Accelerated degradation studies performed at the MHRA over a period of 4 years suggest that the freeze-dried candidate standard will be very stable. The candidate standard was established as Ph. Eur. BRP for Human tetanus immunoglobulin, batch 2 with an assigned potency of 45 IU/ampoule. The same preparation was also adopted by the WHO Expert Committee on Biological Standardization (ECBS) to serve as the WHO 2nd IS for Tetanus Immunoglobulin, Human (13/240).


Asunto(s)
Antitoxinas , Tétanos , Humanos , Calibración , Europa (Continente) , Estándares de Referencia , Antitoxina Tetánica
3.
Pharmeur Bio Sci Notes ; 2024: 1-11, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38252512

RESUMEN

This publication describes the outcome of a project to develop a replacement European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) for Human tetanus immunoglobulin (TIg) as well as for the World Health Organization (WHO) International Standard (IS) for Tetanus Immunoglobulin, Human. Bulk TIg was kindly provided by a European manufacturer and was used to prepare the candidate standard. The candidate standard was freeze-dried and calibrated in an international collaborative study jointly co-ordinated by the Medicines & Healthcare products Regulatory Agency (MHRA) and the European Directorate for the Quality of Medicines & HealthCare (EDQM, Council of Europe). The results of this study show that there was good agreement between laboratories for the potency estimates obtained for the candidate standard relative to the current WHO IS/Ph. Eur. BRP. The study also demonstrated that the candidate standard is suitable for use in Ph. Eur. assays for potency testing of TIg products and there was good agreement in the potency estimates obtained using the different assay methods included in the study. Accelerated degradation studies performed at the MHRA over a period of 4 years suggest that the freeze-dried candidate standard will be very stable. The candidate standard was established as Ph. Eur. BRP for Human tetanus immunoglobulin, batch 2 with an assigned potency of 45 IU/ampoule. The same preparation was also adopted by the WHO Expert Committee on Biological Standardization (ECBS) to serve as the WHO 2nd IS for Tetanus Immunoglobulin, Human (13/240).


Asunto(s)
Antitoxinas , Tétanos , Humanos , Antitoxina Tetánica , Bioensayo , Europa (Continente)
4.
Gynecol Oncol ; 181: 1-7, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38096673

RESUMEN

OBJECTIVE: To describe the participation of racial and ethnic minority groups (REMGs) in gynecologic oncology trials. METHODS: Gynecologic oncology studies registered on ClinicalTrials.gov between 2007 and 2020 were identified. Trials with published results were analyzed based on reporting of race/ethnicity in relation to disease site and trial characteristics. Expected enrollment by race/ethnicity was calculated and compared to actual enrollment, adjusted for 2010 US Census population data. RESULTS: 2146 gynecologic oncology trials were identified. Of published trials (n = 252), 99 (39.3%) reported race/ethnicity data. Recent trials were more likely to report these data (36% from 2007 to 2009; 51% 2013-2015; and 53% from 2016 to 2018, p = 0.01). Of all trials, ovarian cancer trials were least likely to report race/ethnicity data (32.1% vs 39.3%, p = 0.011). Population-adjusted under-enrollment for Blacks was 7-fold in ovarian cancer, Latinx 10-fold for ovarian and 6-fold in uterine cancer trials, Asians 2.5-fold in uterine cancer trials, and American Indian and Alaska Native individuals 6-fold in ovarian trials. Trials for most disease sites have enrolled more REMGs in recent years - REMGs made up 19.6% of trial participants in 2007-2009 compared to 38.1% in 2016-2018 (p < 0.0001). CONCLUSION: Less than half of trials that published results reported race/ethnicity data. Available data reveals that enrollment of REMGs is significantly below expected rates based on national census data. These disparities persisted even after additionally adjusting for population size. Despite improvement in recent years, additional recruitment of REMGs is needed to achieve more representative and equitable participation in gynecologic cancer clinical trials.


Asunto(s)
Neoplasias de los Genitales Femeninos , Neoplasias Ováricas , Neoplasias Uterinas , Humanos , Femenino , Estados Unidos , Neoplasias de los Genitales Femeninos/terapia , Etnicidad , Minorías Étnicas y Raciales , Grupos Minoritarios , Neoplasias Ováricas/terapia , Neoplasias Uterinas/terapia
5.
J Memb Sci ; 584: 343-352, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31423048

RESUMEN

The integration of membrane distillation with reverse electrodialysis has been investigated as a sustainable sanitation solution to provide clean water and electrical power from urine and waste heat. Reverse electrodialysis was integrated to provide the partial remixing of the concentrate (urine) and diluate (permeate) produced from the membrane distillation of urine. Broadly comparable power densities to those of a model salt solution (sodium chloride) were determined during evaluation of the individual and combined contribution of the various monovalent and multivalent inorganic and organic salt constituents in urine. Power densities were improved through raising feed-side temperature and increasing concentration in the concentrate, without observation of limiting behaviour imposed by non-ideal salt and water transport. A further unique contribution of this application is the limited volume of salt concentrate available, which demanded brine recycling to maximise energy recovery analogous to a battery, operating in a 'state of charge'. During recycle, around 47% of the Gibbs free energy was recoverable with up to 80% of the energy extractable before the concentration difference between the two solutions was halfway towards equilibrium which implies that energy recovery can be optimised with limited effect on permeate quality. This study has provided the first successful demonstration of an integrated MD-RED system for energy recovery from a limited resource, and evidences that the recovered power is sufficient to operate a range of low current fluid pumping technologies that could help deliver off-grid sanitation and clean water recovery at single household scale.

6.
J Vestib Res ; 27(1): 27-37, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28387693

RESUMEN

BACKGROUND: The search for reliable and valid signs and symptoms of mild traumatic brain injury (mTBI), commonly synonymous with concussion, has lead to a growing body of evidence that individuals with long-lasting, unremitting impairments often experience visual and vestibular symptoms, such as dizziness, postural and gait disturbances. OBJECTIVE: Investigate the role of visual-vestibular processing deficits following concussion. METHODS: A number of clinically accepted vestibular, oculomotor, and balance assessments as well as a novel virtual reality (VR)-based balance assessment device were used to assess adults with post-acute concussion (n = 14) in comparison to a healthy age-matched cohort (n = 58). RESULTS: Significant between-group differences were found with the VR-based balance device (p = 0.001), with dynamic visual motion emerging as the most discriminating balance condition. The symptom reports collected after performing the oculomotor and vestibular tests: rapid alternating horizontal eye saccades, optokinetic stimulation, and gaze stabilization, were all sensitive to health status (p < 0.05), despite the absence of oculomotor abnormalities being observed, except for near-point convergence. The BESS, King-Devick, and Dynamic Visual Acuity tests did not detect between-group differences. CONCLUSION: Postural and visual-vestibular tasks most closely linked to spatial and self-motion perception had the greatest discriminatory outcomes. The current findings suggest that mesencephalic and parieto-occipital centers and pathways may be involved in concussion.


Asunto(s)
Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/psicología , Enfermedades Vestibulares/etiología , Enfermedades Vestibulares/psicología , Trastornos de la Visión/etiología , Trastornos de la Visión/psicología , Conmoción Encefálica/complicaciones , Conmoción Encefálica/psicología , Convergencia Ocular , Mareo/complicaciones , Mareo/psicología , Femenino , Trastornos Neurológicos de la Marcha/complicaciones , Trastornos Neurológicos de la Marcha/psicología , Humanos , Masculino , Enfermedades del Nervio Oculomotor/etiología , Enfermedades del Nervio Oculomotor/fisiopatología , Equilibrio Postural , Seguimiento Ocular Uniforme , Reflejo Vestibuloocular , Movimientos Sacádicos , Pruebas de Función Vestibular , Realidad Virtual , Agudeza Visual , Adulto Joven
7.
J Forensic Sci ; 61(5): 1356-8, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27373193

RESUMEN

We tested procedures for removing adipocere from insect samples to allow identification. An acceptable procedure was determined: (i) Samples were sorted in petri dishes with 75% alcohol to remove any larvae, adult insects, or other soft-bodied material. (ii) Samples of up to 24 puparia were placed in a vial with 15 mL of 95% acetone, capped, and vortexed for a total of 30-90 sec in 10- to 15-sec bursts. This step removed large masses of adipocere or soil from specimen. (iii) Specimens were removed from acetone and placed in a vial of 15 mL of 2% potassium hydroxide (KOH) and vortexed in 10- to 15-sec bursts until all puparia appeared clean (with our samples this required a total of 60-120 sec). (iv) Specimens were removed from the 2% KOH, placed in 75% ethanol, and examined microscopically. (v) Material was stored in 75% ethanol for identification and long-term preservation.


Asunto(s)
Dípteros , Entomología , Ciencias Forenses , Animales , Larva , Cambios Post Mortem , Pupa , Manejo de Especímenes
8.
Int J Sports Med ; 37(9): 738-47, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27176886

RESUMEN

In this study, we collected and analyzed preliminary data for the internal consistency of a new condensed model to assess vestibular and oculomotor impairments following a concussion. We also examined this model's ability to discriminate concussed athletes from healthy controls. Each participant was tested in a concussion assessment protocol that consisted of the Neurocom's Sensory Organization Test (SOT), Balance Error Scoring System exam, and a series of 8 vestibular and oculomotor assessments. Of these 10 assessments, only the SOT, near point convergence, and the signs and symptoms (S/S) scores collected following optokinetic stimulation, the horizontal eye saccades test, and the gaze stabilization test were significantly correlated with health status, and were used in further analyses. Multivariate logistic regression for binary outcomes was employed and these beta weights were used to calculate the area under the receiver operating characteristic curve ( area under the curve). The best model supported by our findings suggest that an exam consisting of the 4 SOT sensory ratios, near point convergence, and the optokinetic stimulation signs and symptoms score are sensitive in discriminating concussed athletes from healthy controls (accuracy=98.6%, AUC=0.983). However, an even more parsimonious model consisting of only the optokinetic stimulation and gaze stabilization test S/S scores and near point convergence was found to be a sensitive model for discriminating concussed athletes from healthy controls (accuracy=94.4%, AUC=0.951) without the need for expensive equipment. Although more investigation is needed, these findings will be helpful to health professionals potentially providing them with a sensitive and specific battery of simple vestibular and oculomotor assessments for concussion management.


Asunto(s)
Traumatismos en Atletas/diagnóstico , Conmoción Encefálica/diagnóstico , Atletas , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , Masculino , Análisis Multivariante , Equilibrio Postural , Curva ROC , Movimientos Sacádicos , Enfermedades Vestibulares/diagnóstico , Pruebas de Función Vestibular , Pruebas de Visión , Adulto Joven
9.
Int J Sports Med ; 37(5): 405-10, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26859643

RESUMEN

This study intended to examine effects of repetitive sub-concussive head impacts on ocular near point of convergence (NPC). 20 healthy young adult soccer players were assigned to either a heading or control group. Heading subjects completed 10 headers of soccer balls projected at a speed of 11.2 m/s. Control subjects did not perform heading. Linear head acceleration was measured with a triaxial accelerometer. The NPC assessment was performed at pre-, 0 h post-, and 24 h post-heading. During the NPC assessment participants were seated and a visual target was moved towards the eyes at 1cm/sec. The participant signaled when he/she experienced diplopia or deviation of the eye was observed, and the distance was recorded. The assessment was repeated twice and average NPC scores were used for further analysis. Soccer heading induced mean group head accelerations of 14.49±5.4 g. Mild head impacts led to an increased NPC distance, which was supported by a significant Group x Time interaction. In the heading group, 0 h post- and 24 h post-heading NPC scores were significantly receded compared to baseline. Conversely, NPC scores for the control group showed no difference over time. Our findings indicate that mild frontal head impacts affekt NPC for a minimum of 24 h-post heading, suggesting that oculomotor processes are disrupted, at least transiently, by repetitive mild head impact.


Asunto(s)
Traumatismos Craneocerebrales/fisiopatología , Fijación Ocular , Cabeza/fisiopatología , Fútbol/lesiones , Aceleración , Adolescente , Diplopía/fisiopatología , Femenino , Humanos , Masculino , Adulto Joven
11.
PeerJ ; 1: e169, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24109554

RESUMEN

How behavioral patterns are related to niche partitioning is an important question in understanding how closely related species within ecological communities function. Behavioral niche partitioning associated with thermoregulation is well documented in tiger beetles as a group. Co-occurring species of salt flat tiger beetles have adapted many thermoregulatory behaviors to cope with this harsh ecosystem. On first examination these beetles appear to occur in overlapping microhabitats and therefore compete for resources. To determine if behavioral niche partitioning is allowing multiple species to occur within the same harsh salt flat ecosystem we observed Cicindela nevadica lincolniana, Cicindela circumpicta, Cicindela fulgida, and Cicindela togata between 8:00 h and 21:00 h and recorded all behaviors related to thermoregulation using a digital voice recorder. Results of this study strongly indicate that competition among these species for resources has been reduced by the adaptation of different thermoregulatory behaviors such as spending time in shallow water, avoiding the sun during the hottest parts of the day, and by positioning their body against or away from the soil. The endangered C. n. lincolniana appears to rely most heavily on the shallow water of seeps for their diurnal foraging behavior (potentially limiting their foraging habitat), but with the advantage of allowing foraging during the hottest times of the day when potential competitors are less frequent. Ironically, this association also may help explain C. n. lincolniana's susceptibility to extinction: beyond the loss of saline wetlands generally, limited seeps and pools even within remaining saline habitat may represent a further habitat limitation within an already limited habitat.

12.
Int J Sports Med ; 34(4): 350-4, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23175178

RESUMEN

This study intended to determine if an acute bout of soccer heading alters postural control and pronounced self-reported symptoms of cerebral concussion. Collegiate soccer players were randomly assigned to one of 2 groups. Each participant completed a baseline postural control assessment prior to heading. Participants either simulated (control group; CG) or performed (experimental group; EG) 10 headers at 11.2 m/s in 10 min. The postural assessment was repeated post heading at hrs 1, 24, and 48. The postural control parameter assessed was the root mean square (RMS) of the center of mass (COM). COM RMS were calculated for the anterior-posterior (AP) and medial-lateral (ML) time series. Compared to the CG, for the AP and ML time series COM RMS values were significantly higher in the EG at hr 24 (p <0.05). An acute bout of heading results in quantifiable alterations in postural control that are detectable 24 h post heading and dissipate within an additional 24 h. The significant findings may be due to the dynamic postural control assessment that incorporated robust discordant environmental conditions.


Asunto(s)
Equilibrio Postural/fisiología , Fútbol/fisiología , Análisis de Varianza , Conmoción Encefálica/fisiopatología , Femenino , Cabeza , Humanos , Masculino , Factores de Tiempo , Adulto Joven
13.
Pharmeur Bio Sci Notes ; 2011(1): 1-26, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21619853

RESUMEN

A joint collaborative study was organised by the European Directorate for the Quality of Medicines & HealthCare (EDQM) and the World Health Organization (WHO)/National Institute for Biological Standards and Control (NIBSC) to establish replacement batches for the European Pharmacopoeia (Ph. Eur.) Tetanus Vaccine (adsorbed) Biological Reference Preparation (BRP) batch 2 and for the WHO 3rd International Standard (IS) for Tetanus toxoid (adsorbed). Two freeze-dried stabilised tetanus vaccine (adsorbed) candidate preparations (Preparation A, 08/218 and Preparation B, 08/102) were calibrated against the current 3rd IS/BRP batch 2 (Preparation C) using challenge methods in guinea pigs and mice as described in the Ph. Eur. general chapter 2.7.8. Assay of tetanus vaccine (adsorbed). They were also assayed by serology methods. The WHO 2nd IS for Tetanus toxoid adsorbed (TEXA-2) was additionally included in the sample panel as Preparation D. Thirty-four laboratories (regulatory organisations and manufacturers) from 22 countries participated in the collaborative study. The majority of participants performed 2 independent challenge tests. Nine laboratories performed challenge assays in guinea pigs and 30 laboratories performed challenge assays in mice. Eight laboratories performed serology in guinea pigs and 1 laboratory performed serology in mice. For Preparation A, the geometric mean (GM) potency estimate (with 95 % confidence interval (CI)) in guinea pigs for all laboratories that provided valid results (n = 6) was 488.5 (354.2-673.6) IU/ampoule. For valid mouse assays (n = 25) the GM potency (with 95 % CI) was 259.8 (223.5-302.0) IU/ampoule. The inter-laboratory geometric coefficient of variation (GCV) was 36 % for guinea pig assays and 45 % for mouse assays. This compared favourably with the calibration of the 3rd IS/BRP batch 2 where the inter-laboratory GCV was 36 % and 42 % in guinea pigs and mice, respectively. For Preparation B, the GM potency estimate (with 95 % CI) in guinea pigs for all laboratories that provided valid results (n = 6) was 107.9 (64.1-181.7) IU/ampoule. For valid mouse assays (n = 24) the GM potency (with 95 % CI) was 147.9 (126.3-173.1) IU/ampoule. The inter-laboratory GCV was 64.3 % for guinea pig assays and 45.2 % for mouse assays. From the collaborative study, Preparation A appeared more suitable to be the replacement Ph. Eur. BRP as it is similar to the Tetanus vaccine (adsorbed) BRP batch 2, except for nature of the stabiliser. Preparation A was confirmed to have higher potency, readily detectable tetanus toxoid, and confirmed satisfactory stability and performance in challenge assays. Preparation A was adopted in January 2011 by the Ph. Eur. Commission as the Tetanus vaccine (adsorbed) BRP batch 3, with assigned potencies of 490 IU/ampoule in the guinea pig challenge assay and of 260 IU/ampoule in the mouse challenge assay. The same Preparation A was adopted in October 2010 as the WHO 4th IS for Tetanus toxoid (adsorbed), with the assigned activity of 490 IU/ampoule from guinea pig challenge assays. A follow-up study (reporting study) was organised by the EDQM to assess the impact of the potency assigned to the BRP batch 3 for mouse challenge assays on the outcome of batch release testing in Europe. Eight laboratories including official medicines control laboratories (OMCLs) and manufacturers reported the results of their routine testing, using the BRP batch 3 in addition to their regular reference preparation. For each tested product, participants calculated the potency relative to their routine reference and relative to the BRP batch 3. No common sample panel was distributed to participants. In total, data on 40 batches of different marketed tetanus vaccines were reported. Overall, a good concordance was observed between the potencies calculated relative to the BRP batch 2 and relative to the BRP batch 3. On average, the potency estimates were 10 % lower when expressed relative to the BRP batch 3. Cases of discrepant decisions for batch release were very limited and affected mainly batches with specifications close to the pharmacopoeial requirements. The reasons for differences in estimated potencies are discussed. The study showed that the use of the BRP batch 3 with an assigned potency of 260 IU/ampoule does not result in substantial change in the potency of different marketed products. This confirmed that the mouse challenge potency value assigned to the BRP batch 3 is suitable.


Asunto(s)
Bioensayo/normas , Farmacopeas como Asunto , Tecnología Farmacéutica/normas , Toxoide Tetánico/normas , Adsorción , Américas , Animales , Asia , Australia , Calibración , Relación Dosis-Respuesta a Droga , Estabilidad de Medicamentos , Europa (Continente) , Cobayas , Cooperación Internacional , Ratones , Variaciones Dependientes del Observador , Parálisis/inducido químicamente , Control de Calidad , Estándares de Referencia , Reproducibilidad de los Resultados , Pruebas Serológicas/normas , Toxoide Tetánico/química , Toxoide Tetánico/inmunología , Toxoide Tetánico/toxicidad
14.
Biologicals ; 37(1): 1-7, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18805022

RESUMEN

Tetanus toxoid is a vital primary reference material used for standardization of assays required to establish the antigenic purity of tetanus toxoid for vaccine production. Several formulations were assessed and ampouled fills of each formulation lyophilised. The relative Lf content determined by Ramon flocculation, SRD, and ELISA assays was measured. The stability of the tetanus toxoid activity in each formulation was assessed by accelerated degradation studies. Formulations containing glycine were not suitable in flocculation tests but both sorbitol and trehalose formulations were. The trehalose/sodium chloride formulation had a good appearance, showed good activity in all assays and maintained its activity best under stress conditions. This formulation has been applied to a large scale batch of ampoules prepared as a WHO candidate replacement standard, evaluated in a collaborative study and accepted as a replacement WHO IS for use in flocculation test (WHO ECBS, October 2007, ref no BS/07.2061). The stability of this formulation was also excellent for the large scale batch. The benefits of using thermal analysis and freeze drying microscopy coupled with small scale lyophilisation trials in order to screen formulations for the preparation of batches of biological reference materials are demonstrated.


Asunto(s)
Química Farmacéutica/métodos , Toxoide Tetánico/química , Toxoide Tetánico/normas , Química Farmacéutica/normas , Microscopía por Crioelectrón , Análisis Diferencial Térmico , Formas de Dosificación , Composición de Medicamentos , Estabilidad de Medicamentos , Pruebas de Floculación , Liofilización , Estándares de Referencia , Temperatura , Conductividad Térmica
15.
Biologicals ; 36(5): 315-26, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18676158

RESUMEN

The 1st International Reference Reagents (IRR) of Diphtheria and Tetanus Toxoids for Flocculation Test (DIFT and TEFT) were established by the WHO in 1988. These reagents are essential for the standardization of assays used to calculate Lf units of toxoids. Candidate replacement materials were provided by several European vaccine manufacturers and were formulated and freeze-dried at NIBSC. This paper provides a summary of the results of an international collaborative study including 18 laboratories from 16 countries, which examined the candidate replacement materials in a variety of methods. Materials 02/176 and 04/150 were proposed and adopted by the Expert Committee on Biological Standardization of WHO in October 2007 as 2nd WHO International Standards of Diphtheria and Tetanus Toxoid for use in Flocculation Test. The replacement standards were assigned the value of 1100 and 690Lf/ampoule, respectively, based on results of flocculation tests carried out using provided reagents. Material coded 02/176 fully complied with the WHO specifications for stability, residual moisture content, precision of fill and sterility. Stability of material coded 04/150 was slightly lower than expected but predictions were based only on 2-year data and were to be further monitored, post-adoption.


Asunto(s)
Toxoide Diftérico/análisis , Toxoide Diftérico/normas , Pruebas de Floculación/métodos , Pruebas de Floculación/normas , Toxoide Tetánico/análisis , Toxoide Tetánico/normas , Calibración , Difusión , Liofilización , Estándares de Referencia , Temperatura , Organización Mundial de la Salud
16.
J Econ Entomol ; 100(4): 1268-75, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17849879

RESUMEN

The soybean aphid, Aphis glycines Matsumura, was introduced to north central North America from Asia in 2000, and it has become a major pest of soybean, Glycine max (L.) Merr. Understanding how natural enemies impact aphid populations in the field is an important component in developing a comprehensive management plan. We examined the impact of naturally occurring predators in the field by using exclusion cages during July-August 2004 and 2005. Field cages of different mesh diameters were used to exclude different sizes of natural enemies from aphid-infested plots. Plots were surveyed twice weekly for A. glycines and natural enemies. Densities were recorded. Cage effects on mean temperature and soybean growth were found to be insignificant. Significant differences in aphid density were found between treatments in both years of the study (2004 and 2005); however, aphid densities between years were highly variable. Orius insidiosus (Say) was the most commonly occurring predator in the field. Other natural enemies were present in both years but not in high numbers. Parasitoids were present in both years, but their numbers did not suppress aphid densities. Treatment differences within years were related to the abundance of natural enemies. The large differences in aphid abundance between years were associated with the higher number of O. insidiosus found in the field in 2005 (416 total O. insidiosus) than in 2004 (149 total O. insidiosus). This study suggests that naturally occurring predators, primarily O. insidiosus, can have a large impact on A. glycines populations when predator populations are established before initial A. glycines colonization.


Asunto(s)
Áfidos/fisiología , Glycine max , Animales , Heterópteros/fisiología , Mortalidad , Nebraska , Dinámica Poblacional , Conducta Predatoria
17.
Toxicon ; 48(3): 246-54, 2006 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16870221

RESUMEN

In this study, we have compared two in vivo assay methods to measure the type A botulinum toxin neutralising activity of specific immunoglobulin G (IgG) and its fragments (F(ab')(2), Fab', Fab) purified from pentavalent botulinum antisera raised in goats. Each assay method was repeated on three separate occasions in mice and relative potencies calculated with respect to a type A equine reference antitoxin. The conventional assay, which measures the number of mice surviving typically after 72 or 96 h following the intraperitoneal administration of a mixture of toxin and antitoxin, gave the following order of potency IgG>F(ab')(2)>Fab'>Fab (6.8>4.7>3.5>2.6 IU/mg). Differences in potency are likely to be due to differences in the pharmacokinetics of the antitoxins, which are related to their molecular weight. The alternative local flaccid paralysis assay, where toxin and antitoxin are injected subcutaneously into the left inguinocrural region, gave results with a narrower range of activities: IgG>Fab'>F(ab')(2)>Fab (6.0>5.9>5.5>4.6 IU/mg). Comparison of the two assay methods showed no significant differences for IgG, F(ab')(2) or Fab', although the Fab fragment was significantly more potent in the non-lethal assay probably because of the reduced influence of antitoxin pharmacokinetics in this localised assay. These findings show that a local flaccid paralysis assay provides a less time consuming and more humane alternative to the lethal assay for the potency testing of botulinum IgG and F(ab')(2) antitoxins.


Asunto(s)
Toxinas Botulínicas Tipo A/inmunología , Toxinas Botulínicas Tipo A/toxicidad , Fragmentos de Inmunoglobulinas/inmunología , Inmunoglobulina G/inmunología , Parálisis/inmunología , Animales , Femenino , Ratones , Pruebas de Neutralización
18.
Biologicals ; 30(1): 49-68, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11846430

RESUMEN

Here we report the characterisation of a preparation of tetanus toxoid, adsorbed, and its calibration by 27 laboratories in 19 countries in a joint international collaborative study co-sponsored by World Health Organization (WHO) Expert Committee of Biological Standardization (ECBS) and the European Biological Standardisation Programme of European Directorate for the Quality of Medicines (EDQM), Council of Europe. Calibration was in terms of the Second International Standard (I.S.) for Tetanus Toxoid, Adsorbed, by the established WHO/European Pharmacopoeia (Ph Eur) challenge methods. The replacement standard preparation was found to have a unitage of 469 IU/ampoule on the basis of its calibration in guinea-pigs and 496 IU/ampoule on the basis of its calibration in mice. Assessment, both within the collaborative study and as part of candidate characterisation, indicated satisfactory stability of the candidate preparation. This study also provided some information on the effect of mouse strain on potency testing of tetanus vaccines. A limited assessment of the impact of the replacement standard on testing of current production batches of vaccines was also carried out by four manufacturers. This study did not directly address the serological approaches to potency testing. However, one laboratory offered data from mouse serology assay, which gave comparable estimates to in vivo mouse bioassay. Based on the results of this study and with the agreement of participants, the candidate standard was established as the Third International Standard for Tetanus Toxoid, Adsorbed (coded 98/552) by the WHO Expert Committee of Biological Standardization (ECBS) in November 2000. The same preparation was also established as the second Ph Eur Biological Reference Preparation (Ph Eur BRP, batch no. 2) by the Steering Committee of the Biological Standardisation Programme of the EDQM and approved by the European Pharmacopoeia Commission.


Asunto(s)
Laboratorios/normas , Toxoide Tetánico/química , Toxoide Tetánico/inmunología , Animales , Antígenos/química , Calibración , Química Clínica/normas , Ensayo de Inmunoadsorción Enzimática , Femenino , Cobayas , Humanos , Masculino , Ratones , Reproducibilidad de los Resultados
19.
Neuroreport ; 12(14): 3019-22, 2001 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-11568629

RESUMEN

Early life environmental manipulations have been shown to affect hippocampal-dependent learning, hippocampal volume and cerebral lateralization. In this study, we investigated the effects of neonatal stimulation on hippocampal volumetric asymmetry. Long-Evans hooded rats were exposed to a novel non-home environment 3 min daily for the first 3 weeks of life. Histological measures of the left and right hippocampus were made at 8 months of age. We found that neonatal novelty exposure resulted in a long-lasting change in hippocampal volumetric asymmetry. Specifically, this brief and transient early life stimulation increased the right hippocampal volumetric dominance at mid-adulthood.


Asunto(s)
Ambiente Controlado , Conducta Exploratoria/fisiología , Lateralidad Funcional/fisiología , Hipocampo/crecimiento & desarrollo , Aprendizaje/fisiología , Plasticidad Neuronal/fisiología , Percepción Espacial/fisiología , Animales , Animales Recién Nacidos/anatomía & histología , Animales Recién Nacidos/crecimiento & desarrollo , Animales Recién Nacidos/fisiología , Tamaño de la Célula/fisiología , Dominancia Cerebral , Femenino , Hipocampo/citología , Hipocampo/fisiología , Masculino , Neuronas/citología , Neuronas/fisiología , Tamaño de los Órganos/fisiología , Ratas , Ratas Long-Evans , Caracteres Sexuales
20.
J Virol ; 74(22): 10458-67, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11044090

RESUMEN

Epstein-Barr virus (EBV)-induced B-cell growth transformation, a central feature of the virus' strategy for colonizing the human B-cell system, requires full virus latent gene expression and is initiated by transcription from the viral promoter Wp. Interestingly, when EBV accesses other cell types, this growth-transforming program is not activated. The present work focuses on a region of Wp which in reporter assays confers B-cell-specific activity. Bandshift studies indicate that this region contains three factor binding sites, termed sites B, C, and D, in addition to a previously characterized CREB site. Here we show that site C binds members of the ubiquitously expressed RFX family of proteins, notably RFX1, RFX3, and the associated factor MIBP1, whereas sites B and D both bind the B-cell-specific activator protein BSAP/Pax5. In reporter assays with mutant Wp constructs, the loss of factor binding to any one of these sites severely impaired promoter activity in B cells, while the wild-type promoter could be activated in non-B cells by ectopic BSAP expression. We suggest that Wp regulation by BSAP helps to ensure the B-cell specificity of EBV's growth-transforming function.


Asunto(s)
Linfocitos B/virología , Proteínas de Unión al ADN/metabolismo , Regulación Viral de la Expresión Génica , Herpesvirus Humano 4/genética , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas/genética , Factores de Transcripción/metabolismo , Secuencia de Bases , Línea Celular , Línea Celular Transformada , Transformación Celular Viral , Genes Reporteros , Herpesvirus Humano 4/fisiología , Humanos , Datos de Secuencia Molecular , Mutación , Factor de Transcripción PAX5 , Plásmidos/genética , Factores de Transcripción del Factor Regulador X , Factor Regulador X1 , Transfección
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