bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accuracy of wavefront measurement and the potential effect of erroneous custom corneal correction on the modulation transfer function
Authors: Diaz‐Santana L. , Davies N. , Lara‐Saucedo D. 
Published: March 2003

Purpose:  To assess the accuracy of repeated measurements of ocular aberrations using wavefront sensing in a small group of observers and to assess the potential effect of measurement error on custom corneal correction.Methods:  A Shack–Hartmann wavefront sensor was used to measure the ocular wavefront in nine eyes. Head position was stabilised using a dental bite bar and the pupil centred using a CRT monitor and circular grating. Twenty Shack–Hartmann images were collected for each measurement. Each observer had three sets of measurements taken; the first and the second after careful alignment and the final after regrasping the bite bar in the same position as for the second measurement, but without pupil realignment. The modulation transfer functions for each set were calculated and the effect of ideal custom treatments on the modulation transfer function (MTF) was estimated.Results:  There were highly statistically significant differences in a large number of Zernike modes between the three sets of measurements. The MTFs calculated for the residual wavefronts following ideal custom treatment were below the diffraction limit. The RMS wavefront errors were consistently better for the residual wavefronts obtained using the realigned data than using data taken without pupil realignment.Conclusions:  Sequential measurement of ocular aberrations shows statistically significant differences in a large number of Zernike modes. If aberrations determined by a single measurement are to be used in a custom correction the resulting modulation transfer function is likely to remain below the diffraction limit. Pupil realignment is critical in reduction of the residual root mean square wavefront values to a minimum.
Dietary Supplements for Peri‐ and Early Postmenopausal Women: A Quantitative Proposal Based on Disparities Between Recommendations and Dietary Intakes
Authors: Booth Sarah L. , Nelson Miriam E. , Mason Joel B. , Angelo Giana , Meydani Simin Nikbin 
Published: March 2003

AbstractDietary supplement use is increasingly more popular in the United States. Although dietary supplements are not intended to replace intakes from foods, many formulations contain multiple nutrients at levels equivalent to or greater than their corresponding dietary recommendations. Nutrient doses are often justified by expected benefits. Women in the peri‐ and early postmenopausal stages are becoming the most frequent users of dietary supplements, so consideration of reported dietary intakes by women in this age range (45–60 years) is important for determining appropriate levels of supplementation. Dietary intakes at the 5th percentile among women in this age group meet 20–80% of the recommended intakes for individual nutrients. Therefore, for most nutrients, the difference between recommended dietary intakes and actual intakes reported by the 5th percentile represents an adequate level of supplementation. Exceptions to this strategy exist, which relate to evidence of deficiency in the US, the bioavailability of certain nutrients, and putative health benefits not considered in existing dietary recommendations. For some nutrients, there is an overall lack of scientific evidence that supplementation is required at all.
Nutrition Support for the Patient with Chronic Obstructive Pulmonary Disease
Authors: Paiva Sergio A.R. , Campana Alvaro O. , Godoy Irma 
Published: March 2003

AbstractRates of malnutrition among patients with chronic obstructive pulmonary disease range from 20 to 50%, depending on disease severity. Malnutrition and its associated weight loss have been related to a weakening of respiratory and peripheral muscles, impaired exercise performance, and increased susceptibility to lung infection. Although no single cause of malnutrition has been identified, contributing factors include altered basal metabolism, the presence of inflammatory mediators, and metabolic alterations produced by disease treatment and exacerbations. Each of these elements should be explored during a thorough assessment. Patients who are malnourished or losing weight and those with acute exacerbations of the disease should be considered for nutrition support. Patients can be given supplemental oral feedings when tolerated, but may require enteral or parenteral feeding if intakes are consistently inadequate. The goals of nutrition support are to achieve weight gain, preferentially as muscle mass, and to improve lung and respiratory muscle function, exercise performance, and well being scores.
Ginsengs: A Review of Safety and Efficacy
Authors: Mahady Gail B. , Gyllenhaal Charlotte , Fong Harry H.S. , Farnsworth Norman R. 
Published: March 2003

AbstractBoth Korean and Siberian ginseng are used extensively for the enhancement of mental and physical performance. However, results from recent randomized, controlled clinical trials do not substantiate the purported ergogenic effects of ginseng in healthy individuals. Nevertheless, there is some evidence (both human and animal studies) to suggest that Korean and Siberian ginseng may have health promoting effects by stimulating the immune response. The recommended daily dose for Korean ginseng is 0.5 to 2 g per day of dried root or 100 to 300 mg per day of a standardized extract containing 1.5 to 7% ginsenosides and, for Siberian ginseng, 2 to 3 g per day of dried root or equivalent preparations. Patients should be cautioned not to exceed these dosages, as adverse reactions such as hypertension, diarrhea, nervousness, and insomnia are associated with excessive ingestion. For Korean ginseng, drug interactions have been reported with both phenelzine and warfarin. There is a single case report of an interaction between Siberian ginseng and digoxin; however, the clinical significance has not been established. The use of ginseng is contraindicated for children and women who are pregnant or lactating, while Siberian ginseng should also be avoided by those patients with cardiovascular disease or hypertension (BP>180/90 mmHg).
Oral Health and Nutrition in the Elderly
Authors: Henshaw Michelle M. , Calabrese Joseph M. 
Published: March 2003

AbstractThere is a multidirectional association between nutrition and oral health. Oral diseases such as dental caries (tooth decay), periodontal disease, tooth loss, and oral cancer compromise the condition of teeth and supporting tissues, which, in turn, impacts food choice, nutritional intake, and quality of life. Conversely, nutritional status affects the development and progression of oral diseases. The cyclical nature of this interaction is particularly important in older adults, because elders are at increased risk for both poor nutritional status and oral health problems. Still, an oral health assessment is not a routine component of periodic examinations or nutrition counseling for older adults. To include this oft‐overlooked component of systemic health, health care providers must understand the link between nutrition and oral health and learn how to conduct simple oral health assessments. The knowledge gained from an oral health assessment will help clinicians provide more appropriate nutritional counseling and enable them to screen for and make appropriate referrals for oral health problems that may adversely affect their patients' nutritional status. Simple oral health assessments can be easily administered by health professionals, can be completed in less than five minutes, and may have the potential to improve patients' oral health, nutrition, overall health, and, ultimately, the quality of their lives.
Echinacea: Recommendations for its Use in Prophylaxis and Treatment of Respiratory Tract Infections
Authors: Mahady Gail B. , Qato Dima M. , Gyllenhaal Charlotte , Chadwick Luke , Fong Harry H.S. 
Published: March 2003

Abstract Products containing Echinacea are some of the best selling and most widely used botanical dietary supplements in the United States. Commercial Echinacea extracts are manufactured primarily from 3 Echinacea species, namely Echinacea purpurea (herb, roots, or seeds), E. angustifolia (roots), and E. pallida (roots). Current recommendations for use of these products include oral administration for the prophylaxis and treatment of the common cold, bronchitis, influenza, and bacterial and viral infections of the respiratory tract.Unfortunately, much of the clinical data published prior to 1991 suffered from poor methodology and, therefore, was difficult to assess. However, more recent controlled clinical trials have suggested that while Echinacea may not be effective for the prophylaxis of upper respiratory tract infections, these products may be useful in decreasing the symptoms and duration of illness. In vitro and in vivo studies indicate that the therapeutic effects of Echinacea are due to a stimulation of cellular immune response. The major adverse events reported are allergic reactions, ranging from contact dermatitis to anaphylaxis. Patients with an allergy to plants in the daisy family (Asteraceae) should be instructed not to use products containing Echinacea. No drug interactions have been reported, however, the extracts have been shown to inhibit the activity of cytochrome P450 and, therefore, have the potential to influence drug metabolism. Echinacea‐containing dietary supplements may be used safely in conjunction with antibiotics or sulfa drugs. According to the German Commission E, patients with autoimmune disorders, AIDS, HIV infection, or tuberculosis should not use Echinacea, however, there is little scientific data to substantiate these contraindications.Recommendations for oral dosage and dosage forms are difficult due to the wide variety of preparations and doses used in the clinical trials. However, based on existing data products containing pressed juice or hydroalcoholic extracts, Echinacea purpurea (leaf juice and roots) and E. pallida (roots) have the most convincing data supporting their use.
Dissolution and precipitation processes in deformed amphibolites: an example from the ductile shear zone of the Ryoke metamorphic belt, SW Japan
Authors: Imon R. , Okudaira T. , Fujimoto A. 
Published: March 2003

AbstractThe granitic mylonite zone in the Cretaceous Ryoke metamorphic belt contains deformed amphibolites as thin layers. The amphibolite layers do not exhibit pinch‐and‐swell or boudinage structures, even when contained in a high‐strain granitic mylonite. This mode of occurrence suggests that they were deformed as much as the surrounding granite mylonite. In the highly deformed zone, strongly foliated amphibolites contain Ti‐rich brown amphibole porphyroclasts rimmed by Ti‐poor green amphibole, titanite and chlorite. These porphyroclasts are elongated, forming shear surfaces defined by preferential distribution of the chlorite and titanite. Porphyroclastic plagioclase in the strongly foliated amphibolites consists of two components: an anorthite‐rich core and an anorthite‐poor rim. Based on these observations, the mass‐balanced reaction occurring during deformation is defined as As the reaction products form a weak interconnected matrix, the strain rate of the amphibolites may be controlled by the rate of dissolution–precipitation through fluids. Weakly foliated amphibolites in the low‐strain zone exhibit cataclastic microstructures, whereas the strongly foliated amphibolites do not exhibit such features. These microstructural and chemical changes suggest that high‐strain amphibolites were initially deformed by cataclasis, followed by deformation through metamorphic reactions. During the metamorphism/deformation, old plagioclase grains with high Xan were not stable and dissolved, and new plagioclase grains with low Xan crystallized at the old plagioclase rim. Dissolution of old plagioclase and precipitation of new plagioclase occurred normal to and parallel to the foliation, respectively, reflecting incongruent pressure solution due to differential stress and changes in P–T–H2O conditions. The development of incongruent pressure solution is attributed to increased fluid flux in the strongly foliated amphibolites, as evidenced by the greater abundance of hydration‐reaction products in the strongly foliated amphibolites than in the weakly foliated ones.
Future Directions in Dialysis Quantification
Authors: Lindsay Robert M. , Sternby Jan 
Published: March 2003

ABSTRACTThe influence of dialysis prescription on outcome is well established, and currently the amount of dialysis prescribed is based on small molecular weight toxin removal as represented by the clearance of urea. The “normalized dose of dialysis” (Kt/Vurea) concept is well established. Most techniques for dialysis quantification require that blood samples be taken at the beginning and after the completion of dialysis. The postdialysis sample, however, gives cause for concern because of the “rebound phenomenon” due to nonuniform distribution of urea among body compartments. Blood samples give “indirect” measures of dialysis quantification. Thus direct urea concentration measurements in dialysate may be superior in urea kinetic modeling and these may be made “real time” during dialysis.It is with real‐time monitoring that future advances in dialysis quantification will take place. These will be of two types. The first will analyze blood water or dialysate samples for urea content multiple times throughout the treatment; the second will assess the on‐line clearance of urea using surrogate molecules such as sodium chloride, the clearance being determined by conductivity measurements. On‐line urea monitoring is based on the action of urease on urea in a water solution and measurement of the resultant ammonium ions, which are measured directly by a specific electrode or indirectly by conductivity changes. Differences in blood‐side versus dialysate‐side urea monitors exist which reflect the parameters they can provide, but with both, the standard urea kinetic measurements of Kt/V and nPCR (nPNA) are easily obtainable.A range of additional parameters can be derived from dialysate‐side monitoring such as “whole‐body Kt/V,”“pretreatment urea mass” and “whole‐body urea clearance,” which are worthy of future studies to determine their roles in adequacy assessment. Conductivity clearance measurements are made by examining the conductivity differences between dialysate inlet and outlet measured at two different dialysate inlet concentrations. This allows for the calculation of the electrolyte (ionic) dialysance, which is equal to the “effective” urea clearance, that is, the clearance that takes into account recirculation effects that reduce hemodialysis efficiency. The continuous reading of effective ionic clearance will allow an average value for K to be obtained for that dialysis, and hence the parameter K×t as an indication of dialysis dose is easily and accurately obtained for every treatment. The conductivity technology is cheap and rugged, and thus expanded use can be expected. Urea monitors have an inherent cost and require maintenance, and perhaps will remain researchers' tools for the present. The methodologies can complement each other; the addition of an accurate and independent value for K to dialysate based urea monitoring is like having simultaneous blood‐ and dialysate‐side monitoring, and allows further increase in measurable parameters.
Imaging in the Dialysis Patient: Dialysis Therapies for End‐Stage Renal Disease
Authors: Gokal Ram , Hutchison Alastair 
Published: March 2003

AbstractEnd‐stage renal disease (ESRD) has various causes that may differ according to country and racial group. Whatever the cause, unless the water, salt, electrolytes, and waste products excreted by normal kidneys are removed, their accumulation will result in death. Removal of these products can be variably achieved by either hemodialysis or peritoneal dialysis. The principles and outcomes of these techniques are described, as are their complications. It is important that these two different methods of treatment are not regarded as competitive, but areintegrated, together with renal transplantation where appropriate, into the management of patients with ESRD tooptimize both outcome and quality of life.
Review Articles: Approach to Patients with “Complex” Hemodialysis Access Problems
Authors: Huber Thomas S. , Seeger James M. 
Published: March 2003

AbstractThe approach to patients with “complex” permanent hemodialysis (HD) access problems remains poorly defined. The purpose of this review is to outline our current algorithm for patients presenting for dialysis access and to address the management of specific problems that complicate this objective of establishing permanent access. The key components of the algorithm include noninvasive imaging in the diagnostic vascular laboratory to determine all the possible access configurations and invasive imaging with both venography and arteriography to confirm the optimal choice. The specific access‐related problems addressed include inadequate ipsilateral vein, inadequate arterial inflow, central vein stenosis/occlusion, multiple previous access failures, and obesity. Despite the label of “complex” access problems, it is possible to construct native arteriovenous fistulas (AVFs) in almost all patients presenting for access using the standard principles of vascular surgery that are based on establishing adequate arterial inflow, adequate venous outflow, and selecting an appropriate conduit.
Ethical Issues in Dialysis Aaron Spital, Series Editor: Cardiopulmonary Resuscitation and Dialysis: Outcome and Patients' Views
Authors: Hijazi Fadi , Holley Jean L. 
Published: March 2003

AbstractCardiopulmonary resuscitation (CPR) was initially described as an intervention to be used in otherwise healthy individuals suffering acute cardiorespiratory arrest. Over the years, CPR has been extended to all hospitalized patients unless specific orders not to resuscitate have been written with the informed consent of the patient and/or surrogate. The 14–15% survival to hospital discharge reported for in‐hospital CPR has not changed over the past three decades. Compared with other diseases, chronic kidney disease reduces long‐term survival (more than 6 months) following CPR, and the functional status of the few who survive is often quite poor. Nevertheless, most dialysis patients want to be resuscitated. Unfortunately television shows portraying resuscitation imply that survival after CPR is much more common than it really is. Such misinformation contributes to the overwhelming choice for CPR despite the dismal prognosis. Dialysis unit staff need to educate patients and families about the expected success and complications of CPR as part of the advance care planning process that should now be routine.
Long‐Term Follow‐Up of Patients Treated with Intermittent Hormone Therapy for Advanced Prostate Cancer
Authors: Hruby George , Gurney Howard , Turner Sandra , Berry Martin , Harnett Paul , Gebski Val 
Published: March 2003

ABSTRACTBackground: To determine the feasibility of long‐term use of intermittent hormone therapy (IHT) in patients with advanced prostate cancer.Methods: Sixteen hormone‐naïve patients were commenced on IHT and prospectively reviewed. IHT consisted of goserelin acetate alone (two patients) or combined with an antiandrogen. When the serum prostate specific antigen (PSA) level had fallen to < 4 ng/ml for 3 months, IHT was stopped. When the PSA level rose to > 10 ng/ml, the same treatment was recommenced, constituting one complete cycle comprising both “on‐treatment” and “off‐treatment” phases. This was repeated until hormone independence (HI) occurred.Results: The median length follow‐up was 49.9 months. Considering all patients, a mean of 41% of the total time was spent off hormone treatment, ranging from a median of 4.0 to 7.1 months for each cycle. Fifteen patients finished at least one complete cycle of IHT, and 7 patients completed two or more cycles. Nine patients became HI after a mean time period of 19.5 months. Six men remain on IHT; three are currently in their fourth or fifth cycle of treatment. For patients completing Cycles 1, 2, 3, 4, and 5, the median percentage time spent off treatment during each cycle was 41%, 54%, 58%, 53%, and 58%, respectively.Conclusions: Based on this pilot study, IHT would seem to allow considerable time off therapy without obviously affecting the time to HI. If the current randomized trials of IHT against continuous therapy demonstrate equivalent relapse‐free survival, then quality of life and fiscal end points will be paramount in determining treatment options. An Australian intergroup study to examine these end points has already begun.
Lack of Effect of Aminoglutethimide and Hydrocortisone Added to High‐Dose Bicalutamide for Androgen‐Independent Prostate Cancer
Authors: Bubley Glenn J. , Balk Steven P. , Joyce Robin M. , Taplin Mary‐Ellen 
Published: March 2003

ABSTRACTObjectives: To determine whether hormones derived from the adrenal gland affected the progression of androgen‐independent (AI) prostate cancer for patients already receiving treatment with high‐dose bicalutamide. This was accomplished by using a sequential trial design in which medically or surgically castrated patients with AI prostate cancer whose cancers were progressing while receiving bicalutamide were treated with adrenolytic therapy in the form of aminoglutethimide (AM) and hydrocortisone (HC).Materials and Methods: Sixteen patients with AI prostate cancer were enrolled into this trial. All patients had metastatic disease in the bone, and two patients had additional metastases at other sites. Using prostate specific antigen (PSA) level as an indicator of disease activity, patients initially received bicalutamide therapy, then AM and HC were added to the regimen, and then bicalutamide therapy was discontinued, with each documented PSA level increase (see Figure 1). Clinical Trial Study Design: Patients were treated with sequential hormonal interventions according to the scheme depicted above. imageResults: Four (25%) patients demonstrated PSA level reductions of at least 50% after the initiation of bicalutamide, 150 mg/day. No patient demonstrated a PSA or obvious clinical response to the addition of AM and HC to the regimen. This includes the four patients who were initially sensitive to bicalutamide. Therapy with AM and HC was associated with fatigue and skin rashes. These side effects persisted after the withdrawal of bicalutamide therapy and were therefore attributed to AM and HC therapy.Conclusions: Bicalutamide at high doses seems to effectively block the androgen receptor (AR) from the growth stimulation derived from adrenal hormones. Therefore, the inhibition of adrenal hormone production by AM is not a useful therapeutic maneuver in this setting and is associated with moderate side effects. The activation of the AR pathway in these patients may occur by a mechanism other than stimulation by the androgens derived from the testes or adrenal gland.