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Approximately 10% of flowering plant species conceal their pollen within tube-like poricidal anthers. Bees extract pollen from poricidal anthers via floral buzzing, a behavior during which they apply cyclic forces by biting the anther and rapidly contracting their flight muscles. The success of pollen extraction during floral buzzing relies on the direction and magnitude of the forces applied by the bees, yet these forces and forcing directions have not been previously quantified. In this work, we developed an experiment to simultaneously measure the directional forces and thorax kinematics produced by carpenter bees (Xylocopa californica) during defensive buzzing, a behavior regulated by similar physiological mechanisms as floral buzzing. We found that the buzzing frequencies averaged about 130 Hz and were highly variable within individuals. Force amplitudes were on average 170 mN, but at times reached nearly 500 mN. These forces were 30-80 times greater than the weight of the bees tested. The two largest forces occurred within a plane formed by the bees' flight muscles. Force amplitudes were moderately correlated with thorax displacement, velocity and acceleration amplitudes but only weakly correlated with buzzing frequency. Linear models developed through this work provide a mechanism to estimate forces produced during non-flight behaviors based on thorax kinematic measurements in carpenter bees. Based on the buzzing frequencies, individual bee's capacity to vary buzz frequency and predominant forcing directions, we hypothesize that carpenter bees leverage vibration amplification to increase the deformation of poricidal anthers, and hence the amount of pollen ejected.
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Flores , Polinización , Animales , Abejas , Flores/fisiología , Polen/fisiología , Polinización/fisiología , Tórax , VibraciónRESUMEN
Sleep appears to play an important role in the lives of honey bees, but to understand how and why, it is essential to accurately identify sleep, and to know when and where it occurs. Viewing normally obscured honey bees in their nests would be necessary to calculate the total quantity and quality of sleep and sleep's relevance to the health and dynamics of a honey bee and its colony. Western honey bees (Apis mellifera) spend much of their time inside cells, and are visible only by the tips of their abdomens when viewed through the walls of an observation hive, or on frames pulled from a typical beehive. Prior studies have suggested that honey bees spend some of their time inside cells resting or sleeping, with ventilatory movements of the abdomen serving as a telltale sign distinguishing sleep from other behaviors. Bouts of abdominal pulses broken by extended pauses (discontinuous ventilation) in an otherwise relatively immobile bee appears to indicate sleep. Can viewing the tips of abdomens consistently and predictably indicate what is happening with the rest of a bee's body when inserted deep inside a honeycomb cell? To distinguish a sleeping bee from a bee maintaining cells, eating, or heating developing brood, we used a miniature observation hive with slices of honeycomb turned in cross-section, and filmed the exposed cells with an infrared-sensitive video camera and a thermal camera. Thermal imaging helped us identify heating bees, but simply observing ventilatory movements, as well as larger motions of the posterior tip of a bee's abdomen was sufficient to noninvasively and predictably distinguish heating and sleeping inside comb cells. Neither behavior is associated with large motions of the abdomen, but heating demands continuous (vs. discontinuous) ventilatory pulsing. Among the four behaviors observed inside cells, sleeping constituted 16.9% of observations. Accuracy of identifying sleep when restricted to viewing only the tip of an abdomen was 86.6%, and heating was 73.0%. Monitoring abdominal movements of honey bees offers anyone with a view of honeycomb the ability to more fully monitor when and where behaviors of interest are exhibited in a bustling nest.
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Aim To test the validity and acceptability of an online oral health assessment and biofeedback tool for young patients (under 17) for use in general dental practice.Methods A convenience sample of thirteen practitioners were recruited to test the functionality of a novel version of the Denplan PreViser Patient Assessment tool (DEPPA) developed for young patients (YDEPPA). Dentists who had completed eight or more assessments during a one month window were sent a link to an online feedback survey, comprising eight statements about YDEPPA, with scoring options of 0-10, where a score of 10 indicated complete agreement with the relevant questions. Verbatim comments were encouraged. The clinical data submitted were held in a central database in an encrypted format so that only the user practice could identify individual patients.Results Twelve practitioners completed eight or more assessments and were included in the survey. A total of 175 patient assessments were received. Ten practitioners completed the on-line survey. The statement 'YDEPPA produces a valid measurement of each patient's oral health' received an average feedback score of 8.8. The statement 'The full YDEPPA report is a valuable communication aid' received a score of 9.6. Feedback was generally very positive with all scores >8.2. Constructive critical feedback was received for the caries risk aspect of the YDEPPA protocol, with suggestions made for improving objectivity of data inputs. Eighty-one percent of the verbatim comments received were positive.Conclusions Once the caries risk issues raised by pilot dentists have been addressed, YDEPPA appears suitable as a pragmatic analytical and biofeedback tool for use in general dental practice to assess the oral health of young patients, and to facilitate education and engagement of young patients and their parents/carers in positive health behaviours.
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Salud Bucal , Medición de Riesgo , Adolescente , Niño , Preescolar , Odontólogos , Odontología General , Humanos , Masculino , Encuestas y CuestionariosRESUMEN
Aim The primary research question addressed in this paper was 'are lower than average oral health scores observed for those patients who report problems with general health and high-risk lifestyle factors?'Methods A population analysis was conducted on the first 37,330 patients, assessed by 493 dentists in the UK, to receive a Denplan PreViser Patient Assessment (DEPPA) at their dental practice. The Oral Health Score (OHS) was generated using a mixture of patient-reported factors and clinical findings and is an integrated component of DEPPA. Patients' self-reported risk factors included diabetes status, tobacco use and alcohol consumption. Patients' general health was measured by self-report, that is, a yes/no answer to the question 'have you experienced any major health problems in the last year for example a stroke, heart attack or cancer?' Multivariable linear regression analysis was employed to study the association between the OHS and general health and risk factors for patients in the DEPPA cohort.Results The mean age of participants was 54 years (range 17-101; S.D. 16 years) and the mean OHS for the group was 78.4 (range 0-100; S.D. 10). 1,255 (3%) of patients reported experiencing a major health problem in the previous year. In the fully adjusted model, diabetes, tobacco use, excessive alcohol consumption (three or more drinks per day), and poor overall health in the preceding year were all associated with a statistically significant drop in the mean OHS of patients. Having diabetes was associated with a 1.7 point (95% CI 1.3-2.1, P <0.001) drop in OHS, tobacco use was associated with a 2.7 point (95% CI 2.5-2.9, P <0.001) drop in OHS, and excessive alcohol consumption was associated with a 1.8 point (95% CI 1.3-2.4, P <0.001) drop in OHS. The mean OHS in patients who reported a major health problem in the preceding year was 0.7 points (95% CI 0.2-1.2, P = 0.006) lower than that of patients who did not report a major health problem in the preceding year.Conclusion The current study has demonstrated that patient reported general health and risk factors were negatively associated with an overall composite oral health score outcome in a large population of over 37,000 patients examined by 493 dentists. While the clinical significance of some of the reported associations is unknown, the data lend support to the growing body of evidence linking the oral and systemic health of individuals. Therefore, GDPs may be in a unique position to influence the lifestyle and general health of patients as part of their specific remit to attain and maintain optimal oral health.
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Estilo de Vida , Salud Bucal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Consumo de Bebidas Alcohólicas , Odontólogos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto JovenRESUMEN
AIM: To consider the extent to which the validity and reliability of the Denplan Excel Patient Survey (DEPS) has been confirmed during its development and by its use in general dental practice and to explore methods by which any survey instrument used in general dental practice might be validated and tested for reliability. METHODS: DEPS seeks to measure perceived practice performance on those issues considered to be of greatest importance to patients. Content validity was developed by a literature review and tested in a pilot study. Criterion validity was tested by comparing patient retention in a payment plan for practices achieving the highest DEPS scores with those attaining the lowest scores over a two year period (surveys completed between 2010 and 2012). Reliability was assessed using the test/re-test method for 23 practices with approximately a three year time interval between tests. Internal consistency was tested by comparing Net Promoter Scores (NPS - which is measured in DEPS) attained by practices with their Patient Perception Index (PPI) as measured by the ten core questions in DEPS. RESULTS: Practices in the pilot study strongly endorsed the content validity of DEPS. The 12 practices with the highest scores in the DEPS slightly increased their number of patients registered in Denplan payment plans during a two year period. The 12 lowest scoring practices saw 7% of their patients de-register during the same period. The 23 practices selected for the test/re-test study averaged more than 250 responses for both the test and re-test phases. The magnitude and pattern of their results were similar in both phases, while, on average, a modest improvement in results was observed. Internal consistency was confirmed as NPS results in DEPS closely mapped PPI results. The higher the measurement of perceived quality (PPI) the more likely patients were to recommend the practice (NPS). CONCLUSION: Both through its development and use over the last four years The DEPS has demonstrated good validity and reliability. The authors conclude that this level of validity and reliability is adequate for the clinical/general care audit purpose of DEPS and that it is therefore likely to reliably inform practices where further development are indicated. It is important and quite straightforward to both validate and check the reliability of patient surveys used in general dental practice so that dental teams can be confident in the instrument they are using.
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Atención Odontológica/normas , Odontología General/normas , Calidad de la Atención de Salud , Atención Odontológica/psicología , Humanos , Satisfacción del Paciente , Reproducibilidad de los Resultados , Encuestas y CuestionariosRESUMEN
AIMS: To investigate the relationship between perceived quality and patients' tendencies to recommend a practice to friends and colleagues. METHODS: Data from 64 practices using the Denplan Excel Patient Survey (DEPS) were analysed. The Net Promoter Score (NPS max score 100), developed by Reichheld, is reported to each practice using DEPS. It is claimed that the NPS measures the likelihood that patients will recommend the practice to friends and colleagues. A Patient Perception Index (PPI max score 100) is also reported to practices. The PPI is calculated from the responses to the ten core questions of DEPS on perceived quality. The 64 practices were placed into three groups for data analysis according to their NPS result: group one practices receiving an NPS of less than 80, group two practices receiving an NPS of 80-89 and group three practices receiving an NPS of greater than 89. These groups represented practices scoring statistically significantly (to 90% confidence) below the mean NPS (group one), practices close to the mean NPS (group two) and practices statistically significantly (to 90% confidence) above the mean NPS. RESULTS: Group one practices scored a mean PPI of 73, group two scored a mean PPI of 76 and group three a mean PPI of 80. These differences in values of PPI between the groups are statistically significant (to 90% confidence). Of the ten constituent issues which contribute to PPI, the greatest difference in scoring between group one and group three was found to be around perceived value for money. CONCLUSION: The probability of patients recommending a dental practice seems to rise in direct proportion to favourable perceptions of quality. A perception of 'ideal' value for money is the most highly correlated aspect with a high NPS.
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Atención Odontológica/normas , Amigos , Satisfacción del Paciente , Calidad de la Atención de Salud , Atención Odontológica/psicología , Amigos/psicología , Humanos , Indicadores de Calidad de la Atención de Salud , Encuestas y Cuestionarios , Reino UnidoRESUMEN
AIM: The aim of this paper was to review the oral health and future disease risk scores compiled in the Denplan Excel/Previser Patient Assessment (DEPPA) data base by patient age group, and to consider the significance of these outcomes to general practice funding by capitation payments. METHODS: Between September 2013 and January 2014 7,787 patient assessments were conducted by about 200 dentists from across the UK using DEPPA. A population study was conducted on this data at all life stages. RESULTS: The composite Denplan Excel Oral Health Score (OHS) element of DEPPA reduced in a linear fashion with increasing age from a mean value of 85.0 in the 17-24 age group to a mean of 72.6 in patients aged over 75 years. Both periodontal health and tooth health aspects declined with age in an almost linear pattern. DEPPA capitation fee code recommendations followed this trend by advising higher fee codes as patients aged. CONCLUSIONS: As is the case with general health, these contemporary data suggest that the cost of providing oral health care tends to rise significantly with age. Where capitation is used as a method for funding, these costs either need to be passed onto those patients, or a conscious decision made to subsidise older age groups.
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Capitación/estadística & datos numéricos , Odontología General/economía , Enfermedades de la Boca/epidemiología , Salud Bucal/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Anciano , Caries Dental/economía , Caries Dental/epidemiología , Encuestas de Salud Bucal , Odontología General/estadística & datos numéricos , Humanos , Modelos Lineales , Persona de Mediana Edad , Enfermedades de la Boca/economía , Salud Bucal/economía , Enfermedades Periodontales/economía , Enfermedades Periodontales/epidemiología , Factores de Riesgo , Enfermedades Dentales/economía , Enfermedades Dentales/epidemiología , Reino Unido/epidemiología , Adulto JovenRESUMEN
AIM: To compare the outcomes of a contemporary oral health status (OHS) scoring system with national oral health data from the 2009 Adult Dental Health Survey, and to explore the utility of the OHS in audit and service development. METHODS: An OHS scoring system was developed as part of a previously reported comprehensive on-line patient assessment tool. The assessment tool also measured future disease risk and indicative capitation fee grading. The modified OHS score component was developed over 20 years of research and experience from the original Oral Health Index (Burke and Wilson 1995). The online tool was piloted by 25 volunteer dentists on 640 recall patients and qualitative and quantitative feedback provided. Anonymised data from the inputs and scores generated were collected centrally and analysed using descriptive statistics. RESULTS: The modified OHS was reported to have good validity by the pilot group. Submitted data confirmed a mean age for the recall patients examined as 53 ± 15.8 years and an average oral health status score of 79.5 ± 10.8 where a score of 100 equates to perfect oral health. A breakdown of the scores into the eight principal components provided evidence of cross validation with the Adult Dental Health Survey (2009). CONCLUSIONS: Scoring oral health status electronically offers valuable opportunities for clinical audit. The reported benchmark oral health score of 79.5 for recall patients can be updated as increased numbers of patients enter the centralised data recording system. Audit can be facilitated by this move from a paper-based system to an on-line tool with central data collection.
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Auditoría Clínica/métodos , Salud Bucal/normas , Encuestas de Salud Bucal , Humanos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Factores de Riesgo , Enfermedades Estomatognáticas/diagnóstico , Enfermedades Estomatognáticas/epidemiología , Reino UnidoRESUMEN
Larval and early juvenile fishes were sampled from the eastern Bering Sea (EBS) shelf from 2001 to 2005, and in 2007. Data from these collections were used to examine spatial and temporal patterns in species assemblage structure and abundance. The years 2001-2005 were unusual because the EBS water temperature was 'warm' compared with the long-term mean temperature. In contrast, 2007 was a 'cold' year. The abundance of the five most numerous taxa at 12 stations common to all years sampled (1996-2005, 2007) were significantly different among years. Larval and early juvenile stage Theragra chalcogramma (walleye pollock), a commercially important gadid, were by far the most abundant fish in all years. Bottom depth alone best explained assemblage structure in most years, but in others, bottom depth and water column temperature combined and percent sea-ice coverage were most important. Abundance of T. chalcogramma larvae increases with water column temperature until 5°C and then becomes level. Higher abundances of Gadus macrocephalus (Pacific cod) larvae occur in years with the greatest percent sea-ice cover as indicated by GAM analysis. Larvae of Lepidopsetta polyxystra (northern rock sole) increase in abundance with increasing maximum wind speed, but decrease at a later date during the last winter storm. The data are consistent with the hypothesis that oceanographic conditions, specifically water temperature and sea-ice coverage, affect the spatial and temporal pattern of larval abundances. In general, ichthyoplankton species assemblages can be important early indicators of environmental change in the Bering Sea and potentially other subarctic seas as well.
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AIM: To report the development and evaluation of an evidence-based, online, patient assessment tool, capable of measuring oral health status, future disease risk and capitation fee guidance. METHODS: An online integrated oral health and risk assessment tool called DEPPA was developed, incorporating 1) PreViser(™) risk scores for periodontal disease, caries, non-carious tooth surface loss and oral cancer, 2) revised versions of Denplan Excel's Oral Health Score and 3) capitation fee guidance score. DEPPA was piloted by 25 dentists who provided quantitative and qualitative feedback. RESULTS: Six hundred and forty assessments were performed. There was strong agreement on the need for such a tool, that it constituted a comprehensive assessment and supported good patient communication. The validity of the system was perceived as sound and the revised capitation fee guidance broadly welcomed. While some deemed the caries risk scoring algorithm to be too sensitive, the 30% high/very high risk rating is consistent with current rates of active caries in UK adults. CONCLUSIONS: A viable online oral health and risk-assessment tool has been developed (DEPPA) that will allow dental teams to measure oral health status, future disease risk and receive ongoing guidance on capitation fee setting. The indications are that DEPPA could be a valuable audit, care planning and patient communication tool.
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Salud Bucal , Medición de Riesgo/métodos , Capitación , Atención Odontológica/métodos , Caries Dental/diagnóstico , Odontólogos , Diagnóstico por Computador , Humanos , Neoplasias de la Boca/diagnóstico , Enfermedades Periodontales/diagnóstico , Proyectos PilotoRESUMEN
AIM: To investigate the measurement of oral health self perceptions, as part of a concise patient survey, and to consider the potential value of including this aspect in survey instruments. METHOD: In 2011, the data collected from 42,794 patients attending 276 practices participating in a voluntary accreditation programme patient survey were reviewed, with a particular emphasis on three oral health impact questions (OHIQs) included in the instrument. These three questions were about comfort (pain), function and dental appearance. RESULTS: Patient self perceptions of oral health varied with age. For each of the three OHIQs the percentage of patients reporting 'ideal' health fell with age to some extent, although for each of the OHIQs the percentage of patients reporting 'unacceptable' health remained below 3% and varied little with age. Statistically significant variations from the mean scores for these OHIQs were observed for some of the participating practices, which would not be explained by age variations in their patient sample alone. CONCLUSION: Patient surveys are a useful opportunity to elicit collective feedback from patients on self perceived oral health. When results are benchmarked they can inform practices, particularly when reviewed together with additional relevant data, of opportunities to develop clinical services to produce still higher standards of oral health and wellbeing for their patients.
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Atención Odontológica/estadística & datos numéricos , Salud Bucal/estadística & datos numéricos , Satisfacción del Paciente/estadística & datos numéricos , Autoimagen , Encuestas y Cuestionarios , Adulto , Factores de Edad , Femenino , Encuestas Epidemiológicas/métodos , Humanos , Masculino , Persona de Mediana EdadRESUMEN
AIM: To develop a concise patient feedback audit instrument designed to inform practice development on those issues of greatest importance to patients. METHODS: A literature review was used to establish the issues which were of greatest importance to patients. Ten core questions were then designed with the help of an experienced survey and polling organisation. A challenging grading of patient responses was utilised in an attempt to differentiate perceived performance within a practice on the different aspects and between practices. A feasibility study was conducted using the interactive voice response mode with seven volunteer practices in 2009. The instrument was then used in the later part of 2010 by 61 practices mostly in paper-based format. Practices received feedback which is primarily based on a bar chart plotting their percentage of top grades received against a national reference sample (NRS) compiled from the results of other participating practices. A statistical analysis was conducted to establish the level at which an individual practice result becomes statistically significant against the NRS. RESULTS: The 61 participating practices each received an average of 121 responses (total 7,381 responses). Seventy-four percent of responses across all ten questions received the top grade, 'ideal'. Statistical analysis indicated that at the level of 121 responses, a score of around 4-9% difference to the National Reference Sample, depending on the specific question, was statistically significant. CONCLUSION: In keeping with international experience with dental patient feedback surveys this audit suggests high levels of patient satisfaction with their dental service. Nevertheless, by focusing results on the proportion of highest grades received, this instrument is capable of indicating when perceived performance falls significantly below the average. It can therefore inform practice development.
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Atención Odontológica/normas , Satisfacción del Paciente , Encuestas y Cuestionarios , Competencia Clínica , Recolección de Datos , Estudios de Factibilidad , Humanos , Evaluación de Resultado en la Atención de Salud , Garantía de la Calidad de Atención de Salud/normasRESUMEN
OBJECTIVE: To determine the views of people with multiple sclerosis (MS) and professionals in relation to confidentiality, consent and access to data within a proposed MS register in the UK. DESIGN: Qualitative study using focus groups (10) and interviews (13). SETTING: England and Northern Ireland. PARTICIPANTS: 68 people with MS, neurologists, MS nurses, health services management professionals, researchers, representatives from pharmaceutical companies and social care professionals. RESULTS: People with MS expressed open and altruistic views towards the use of their personal information to facilitate service provision and research, placing trust in responsible guardianship and legitimate use of their information. Participant's proposed that people with MS should be able to select their individual level of involvement in a register using levels of consent. It was agreed that access to the register should be governed by a guardianship committee composed of a range of stakeholders. People with MS did not wish their details to be used by marketing agencies and did not consider this a legitimate use of their data. Whilst participants were positive of the role a register could play in promoting research, participants felt that access to data by pharmaceutical industries should be administered by the guardianship committee. People with MS are concerned should their employers be able to access their personal information. Professionals were more cautious than people with MS in their approach to the use of patient personal data within a register. CONCLUSIONS: Whilst all stakeholders were positive of the benefits of an MS register, development of such a resource must incorporate robust data security and guardianship measures in order to ensure that, whilst opportunities are maximised, risks to the privacy of individuals and legal challenges to professionals are avoided.
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Actitud del Personal de Salud , Actitud Frente a la Salud , Seguridad Computacional/normas , Consentimiento Informado , Esclerosis Múltiple/psicología , Sistema de Registros , Recolección de Datos/métodos , Inglaterra , Humanos , Consentimiento Informado/ética , Consentimiento Informado/psicología , Irlanda del Norte , Investigación Cualitativa , Sistema de Registros/ética , Sistema de Registros/normas , Confianza/psicologíaRESUMEN
OBJECTIVE: To assess the reproducibility of the Denplan Oral Health Score (OHS) and to examine whether general dental practitioners are more reproducible at measuring oral health when they use the OHS than when they use their usual method of examining patients. DESIGN: This was a single centre study designed to compare dentists' reproducibility using the Oral Health Score with their reproducibility when using the method of examination that they normally employ in general practice. SETTING: The study was carried out at The University of Birmingham School of Dentistry during 2001. PARTICIPANTS: Ten local general dental practitioners were recruited by advertising. The patients were selected from various clinics in the University of Birmingham School of Dentistry to provide a broad spectrum of oral health. MAIN OUTCOME MEASURES: The dentists scored oral health by two methods; firstly on a 10 cm linear scale after using their everyday method of examination and secondly using the structured format of the OHS examination, where the Oral Health Scores were expressed as a percentage. RESULTS: Overall, the majority of the participating dentists demonstrated better intra-examiner reproducibility with the OHS than with their own method of examination. There was also higher inter-examiner reproducibility with the OHS than with the dentists' own method.
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Enfermedades de la Boca/clasificación , Salud Bucal , Enfermedades Dentales/clasificación , Odontología General , Estado de Salud , Indicadores de Salud , Humanos , Variaciones Dependientes del Observador , Reproducibilidad de los ResultadosRESUMEN
The sodium salt of heptakis(2-O-methyl-6-O-sulfo)cyclomaltoheptaose (HMS), the second single-isomer, sulfated beta-CD carrying nonidentical substituents at all of the C2, C3, and C6 positions, has been synthesized, analytically characterized, and used for the capillary electrophoretic separation of the enantiomers of a group of 23 weak base analytes in acidic aqueous and methanolic BGEs. HMS interacted strongly with only about half of the analytes studied. The good separation selectivities and favorable normalized EOF mobilities allowed for rapid, efficient separation of the enantiomers of 19 of the 23 weak base analytes in the aqueous BGEs, often with separation selectivity values complimentary to those obtained with other single-isomer sulfated CDs. HMS did not prove to be as good a resolving agent in acidic methanolic BGEs as its counterpart, heptakis(2-O-methyl-3-O-acetyl-6-O-sulfo)cyclomaltoheptaose.
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Electroforesis Capilar/métodos , beta-Ciclodextrinas/síntesis química , Concentración de Iones de Hidrógeno , Metanol , Solventes , Estereoisomerismo , Sulfatos , beta-Ciclodextrinas/químicaRESUMEN
BACKGROUND: Multifocal motor neuropathy with conduction block (MMN) can be mistaken for motor neurone disease or other lower motor neurone syndromes, but is treatable with intravenous immunoglobulin (IvIg). Formal electrophysiological criteria for conduction block (CB) are so stringent that substantial numbers of patients may miss out on appropriate treatment. METHODS: Electrophysiological data were collected from 10 healthy volunteers and compared to data from 10 patients who satisfied the clinical criteria for MMN and who responded to IvIg. This produced a definition of CB in MMN patients which was compared with existing definitions to assess "miss rates". RESULTS: Mean values for compound muscle action potential area, amplitude, and duration were calculated in normal subjects. Results beyond 3 SD of their respective means were considered abnormal. Using these criteria, CB in the context of MMN was defined as a reduction in negative peak area >23% along a distal nerve segment or >29% across a proximal segment; or a reduction in amplitude >32% across a distal segment or >33% across a proximal segment. All IvIg responsive patients had at least one nerve segment showing such CB. Employing some criteria from the literature would have denied treatment to over 30% of responsive patients. CONCLUSION: In the clinical setting of suspected MMN, less stringent criteria for CB can improve the diagnosis of this treatable disorder. Exclusions on grounds of temporal dispersion may be over-restrictive. A little over one third of CBs occur proximally.
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Inmunoglobulinas Intravenosas/uso terapéutico , Enfermedad de la Neurona Motora/diagnóstico , Enfermedad de la Neurona Motora/tratamiento farmacológico , Conducción Nerviosa/fisiología , Potenciales de Acción , Adulto , Estudios de Casos y Controles , Diagnóstico Diferencial , Electrofisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de la Neurona Motora/inmunologíaRESUMEN
BACKGROUND: Multifocal motor neuropathy with conduction block (MMN) is a treatable disorder that can be mistaken for other lower motor neurone syndromes. Existing electrophysiological diagnostic criteria for MMN are restrictive. In particular, many are cautious about diagnosing conduction block (CB) in the presence of abnormal temporal dispersion (TD). OBJECTIVE: To study the significance of TD in MMN, its relationship to CB in intravenous immunoglobulin (IvIg) responsive patients, and its utility in detecting a treatment response. METHODS: We compared pre- and post-treatment changes in CB and TD in nine patients who satisfied clinical and electrophysiological criteria for MMN and responded to IvIg. RESULTS: TD improved in one or more nerve segments in eight of nine patients tested. There was marked improvement in 65% of all nerve segments, and 60% of those segments with CB. By comparison, significant improvement in CB occurred in only 33% of segments. Of segments with significantly better CB after treatment, all but one showed similar improvements in TD. Such changes were not related to the degree of TD before treatment, being seen in segments with abnormal as well as normal TD. There was no correlation between improvements seen in TD and CB. CONCLUSION: We believe that TD should be considered an inherent feature of MMN. Improvement in TD is an independent marker of electrophysiological improvement in this disorder and is likely to be more useful than CB. When MMN is clinically suspected, the use of stringent criteria for CB in the presence of TD should be avoided.
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Inmunoglobulinas Intravenosas/uso terapéutico , Enfermedad de la Neurona Motora/tratamiento farmacológico , Enfermedad de la Neurona Motora/patología , Potenciales de Acción , Adulto , Anciano , Diagnóstico Diferencial , Electrofisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de la Neurona Motora/inmunología , Conducción Nerviosa , Resultado del TratamientoRESUMEN
The sodium salt of heptakis(2-O-methyl-3-O-acetyl-6-O-sulfo)cyclomaltoheptaose (HMAS), the first single-isomer, sulfated beta-cyclodextrin carrying nonidentical substituents at all of the C2, C3, and C6 positions, has been synthesized, analytically characterized, and used for the capillary electrophoretic separation of the enantiomers of a group of 24 weak base pharmaceuticals in acidic aqueous and acidic methanolic background electrolytes. HMAS interacted more strongly with most of the analytes studied than heptakis(2,3-di-O-methyl-6-O-sulfo)cyclomaltoheptaose, but less strongly than heptakis(2,3-di-O-acetyl-6-O-sulfo)cyclomaltoheptaose, the respective analogs with identical substituents at the C2 and C3 positions. The good separation selectivities and favorable normalized electroosmotic flow mobilities allowed for rapid, efficient separation of the enantiomers of 19 of the 24 weak base analytes in the aqueous and methanolic background electrolytes. The trends in the effective mobilities and separation selectivities as a function of the HMAS concentration closely followed the predictions of the ionic strength-corrected charged resolving agent migration model.