The hyperbolic parabola is commonly used to summarize kinetics for enzyme reactions and receptor binding kinetics. Depending on the experimental conditions, certain assumptions are valid but others ...might be violated so that the parameters used to fit this hyperbolic function, the maximum asymptote and the equilibrium constant, require different interpretations. The first topic of this review compares enzyme-induced transformations and receptor binding in terms of the appropriate assumptions. The second topic considers the complication of adding a competitive inhibitor as an enzyme substrate or a receptor ligand and the subtleties of inferring the equilibrium dissociation constant from the concentration of inhibitor (for example unlabeled drug) that leads to the midpoint, IC
50, of an inhibition curve. Receptor binding may be measured directly by a concentration assay or as a pharmacodynamic response variable.
There are options available to patients newly diagnosed with vestibular schwannoma. Our institution employs stereotactic radiosurgery, microsurgical removal, and watchful waiting. There are no ...studies in the literature examining which of these treatment options patients are choosing.
Using retrospective chart review from January 2000 through December 2001, we noted several variables and patients' initial treatment choices.
During the 24-month study period, 139 patients were seen at our institution with a new diagnosis of vestibular schwannoma and made a clear initial treatment choice. Of these, 32 (23%) patients elected watchful waiting; 51 (36%) underwent stereotactic radiosurgery, and 56 (40%) underwent surgical removal. Surgical excision correlated with younger age and larger tumor size.
Our initial hypothesis, that patients choosing treatment would choose stereotactic radiosurgery more than 50% of the time, was untrue for the time course studied.
This is the first study to examine patient choice in treatment of vestibular schwannoma.
Food and nutrition insecurity continues to be one of the major development challenges in sub-Saharan Africa and other developing regions of the world. Karamoja sub-region, located in northern Uganda, ...is one of the poorest and most food insecure part of Eastern Africa. Previous studies have generalized the sub-region as food insecure. However, limited attention has been paid to locational differences in the food and nutrition security situation within this culturally and ecologically diverse part of the country. A cross-sectional study design was used to examine at a community level, disparity in food and nutrition security situation among communities in Kotido and Moroto districts of the Karamoja sub-region. The study investigated the status of agricultural production, dietary habits and food security situation using individual household survey, focus group discussions, key informant interviews, household food insecurity access scale (HFIAS) and food insecurity coping strategy index (CSI). Data were analyzed using descriptive statistics, analysis of variance, and correlation and regression methods, at 5% level of significance. The results showed that irrespective of ethnic differences, majority of households (78.8%) consumed less than 3 meals 24 hours preceding the interview. Generally, agricultural production was inadequate to support household food security and less than 30% of the households had adequate calorie intake. However, calorie intake adequacy was at least three (3) times higher in Kotido than in Moroto district. Plant foods were more frequently consumed than animal-source foods. At least 57% and 73% of households in Kotido and Moroto districts, respectively, never consumed fish. Food security was generally predicted by household size, ownership of food stores, occupation of household caregivers, number of livestock (especially goats) owned by households, time taken to fetch water (related to distance to water source) and sorghum production. Whereas it is generally known that Karamoja sub-region is highly food insecure, this study has demonstrated that communities in Moroto district are worse-off than those in Kotido district. Therefore, community-level characteristics ought to be an essential baseline consideration in designing food and nutrition interventions in Karamoja, and indeed in food insecure localities in general.
Objective:
To describe the presentation and clinical course of internal auditory canal (IAC) and cerebellopontine angle (CPA) lipomas.
Design:
Retrospective chart review at a single tertiary referral ...center.
Methods:
All patients presenting with an IAC or CPA mass radiographically consistent with a lipoma on high-resolution magnetic resonance imaging (MRI) were identified. Data including presenting symptomatology, tumor characteristics, management strategy, and patient course were collected.
Results:
Between 1996 and 2012, 19 patients were evaluated and diagnosed with a CPA/IAC lipoma. Four patients with incomplete medical record data were excluded. The mean age of the remaining 15 patients was 43.4 years, and the average duration of follow-up was 4.3 years (range, 0.1–15.8 years). Eight lesions were isolated to the IAC, while seven involved the CPA (mean diameter 10.1 mm). The most common presenting symptoms were mild sensorineural hearing loss (40%) and tinnitus (33%); seven patients were diagnosed after incidental discovery on MRI. Fourteen patients were managed with observation, and 1 underwent subtotal resection at an outside facility resulting in incomplete facial nerve paralysis, severe sensorineural hearing loss, and lower cranial nerve dysfunction.
Conclusion:
While rare, lipomas should be included in the differential diagnosis when evaluating CPA and IAC lesions. Owing to a generally benign clinical course, and high morbidity associated with resection, microsurgery should be reserved for those patients with severe symptomatology or definite radiographic progression. Careful radiological evaluation is critical to establishing an accurate diagnosis to prevent unnecessary morbidity associated with resection.
Objectives:
The objectives of this study are to (1) report two cases of intramuscular hemangioma (IMH) of the scalene musculature masquerading as a paraganglioma, and (2) discuss the management of ...IMH of the head and neck (HN).
Design:
Case series and literature review.
Patients/Materials and Methods:
We present two cases of IMH of the scalene. Preoperative radiography and examination findings strongly suggested paraganglioma. Clinical and radiological presentation, histological classifications, and treatment are discussed.
Results:
The most common location for IMH in the HN is the masseter muscle, and to the authors' knowledge there has been only one report involving the scalene musculature. We report two cases of IMH in this location, presenting as a neck mass in a 25-year-old woman and a 21-year-old man. Magnetic resonance angiography and venography demonstrated intensely vascular lesions with salt and pepper flow voids and displacement of the carotid system anteriorly. Laboratory workup was negative, and preliminary diagnosis was a nonsecreting paraganglioma. Angiography was performed preoperatively, and while no feeding vessels were identified in the female patient, the ascending cervical artery was identified and effectively embolized in the male. Both patients underwent neck exploration and were found to have highly vascular lesions intimately associated with the scalene. Histopathology demonstrated benign IMH. Both recovered well with no evidence of recurrent disease.
Conclusions:
IMHs of the scalene musculature are exceedingly rare, and can be difficult to distinguish from paragangliomas. Surgical excision is the treatment of choice. IMH of the scalene muscles should be considered in the differential diagnosis of deep neck space masses.
Context Reproduction is a critical component of fitness, and understanding factors that influence temporal and spatial dynamics in reproductive output is important for effective management and ...conservation. Although several indices of reproductive output for wide-ranging species, such as migratory birds, exist, there has been no theoretical justification for their estimators or associated measures of variance. Aims The aims of our research were to develop statistical justification for an estimator of reproduction and associated variances on the basis of an existing national wing-collection survey and banding data, and to demonstrate the applicability of this estimator to a migratory game bird. Methods We used a Bayesian hierarchical modelling approach to integrate wing-collection data, which provides information on population age ratios, and band-recovery data, which provides information on recovery probabilities of various age classes, for American woodcock (Scolopax minor) to estimate productivity and associated measures of variance. We present two models of relative vulnerability between age classes: one model assumed that adult recovery probabilities were higher, but that annual fluctuations were synchronous between the two age classes (i.e. an additive effect of age and year). The second model assumed that adults, on average, had higher recovery probabilities than did juveniles and that annual fluctuations were asynchronous through time (i.e. an interaction between age and year). Key results Fitting our models within a hierarchical Bayesian framework efficiently incorporates the two data types into a single estimator and derives appropriate variances for the productivity estimator. Further, use of Bayesian methods enabled us to derive credible intervals that avoid the reliance on asymptotic assumptions. When applied to American woodcock data, the additive model resulted in biologically realistic and more precise age-ratio estimates each year and is adequate when the relative vulnerability to sampling only slightly varies or does not vary among components of a population (e.g. age, sex class) among years. Therefore, we recommend using woodcock indices from our analysis based on this model. Conclusions We provide a flexible modelling framework for estimating productivity and associated variances that can incorporate ecological covariates to explore various factors that could drive annual dynamics in productivity. Applying our model to the American woodcock data indicated that assumptions about the variability in relative recovery probabilities could greatly influence the precision of our productivity estimator. Therefore, researchers should carefully consider the assumption of temporally variable relative recovery probabilities (i.e. ratio of juvenile to adults' recovery probability) for different age classes when applying this estimator. Implications Several national and international management strategies for migratory game birds in North America rely on measures of productivity from harvest survey parts collections, without a justification of the estimator or providing estimates of precision. We derive an estimator of productivity with realistic measures of uncertainty that can be directly incorporated into management plans or ecological studies across large spatial scales.
Lotus japonicus handbook Márquez, A. J. (Antonio J.); Stougaard, J
2005, 2005-10-26
eBook, Book
Legumes are very important plants playing a central role in biological research. They are a key component of sustainable agricultural systems because of symbiotic nitrogen fixation and other ...beneficial symbiosis with mycorrhizal fungi. Studies on most of the major leguminous crops are hampered by large genome sizes and other disadvantages which have hindered the isolation and characterisation of genes with important roles in legume biology and agriculture. For this reason Lotus japonicus was chosen as a model species for legume research some ten years ago. Since then, many groups around the world have adopted Lotus as a model and have developed numerous resources and protocols to facilitate basic and applied research on this species. This handbook represents the first effort to compile basic descriptions and methods for research in Lotus, including symbiotic processes, cell and molecular biology protocols, functional genomics, mutants, gene tagging and genetic analysis, transformation and reverse genetic analysis, primary and secondary metabolism, and an exhaustive update of the scientific literature available on this plant.
We report on four radio-detected cosmic-ray (CR) or CR-like events observed with the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload. Two of the four ...were previously identified as stratospheric CR air showers during the ANITA-I flight. A third stratospheric CR was detected during the ANITA-II flight. Here we report on characteristics these three unusual CR events, which develop nearly horizontally, 20-30~km above the surface of the Earth. In addition, we report on a fourth steeply upward-pointing ANITA-I CR-like radio event which has characteristics consistent with a primary that emerged from the surface of the ice. This suggests a possible \(\tau\)-lepton decay as the origin of this event, but such an interpretation would require significant suppression of the Standard Model \({\tau}\)-neutrino cross section.
We have studied hadronic four-body decays of D(+) and D(+)(s) mesons with a K(S) in the final state using data recorded during the 1996-1997 fixed-target run of the Fermilab high energy ...photoproduction experiment FOCUS. We report a new branching ratio measurement of gamma(D(+)-->K(S)K-pi(+)pi(+))/gamma(D(+)-->K(S)pi(+)pi(+)pi(-)) = 0.0768+/-0.0041+/-0.0032. We make the first observation of three new decay modes with branching ratios gamma(D(+)-->K(S)K+pi(+)pi(-))/gamma(D(+)-->K(S)pi(+)pi(+)pi(-)) = 0.0562+/-0.0039+/-0.0040, gamma(D(+)-->K(S)K+K-pi(+))/gamma(D(+)-->K(S)pi(+)pi(+)pi(-)) = 0.0077+/-0.0015+/-0.0009, and gamma(D(+)(s)-->K(S)K+pi(+)pi(-))/gamma(D(+)(s)-->K(S)K-pi(+)pi(+)) = 0.586+/-0.052+/-0.043, where in each case the first error is statistical and the second error is systematic.
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