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PubMedDate not supplied

An experimental study of jejunal pouch replacements following total gastrectomy.

BACKGROUND/AIMS: The nutritional effects of pouch replacement after total gastrectomy remain clinically controversial. Two previous experiments failed to show any nutritional benefit. However, the pouches applied clinically and examined experimentally so far were all of anti-peristaltic type. METHODOLOGY: Male 7- or 8-week-old Wistar rats were divided into 3 experimental groups after total gastrectomy. For group 1 and 2 rats, Roux-en-Y reconstructions and Hunt-Lawrence pouches, i.e., anti-peristaltic type, were performed, respectively. Group 3 rats underwent a new type of iso-peristaltic pouch replacement. Food intake was recorded daily and all rats were weighed once a week. At the end of the 12-week experimental period, there were 9 rats in group 1, 10 in group 2, and 8 in group 3. The volumes of the gastric reservoirs were measured, and blood samples were taken. Five 20-week-old rats served as control of weight, food intake, and laboratory data. RESULTS: The volumes of the gastric reservoirs in group 2 and 3 rats were significantly larger than in group 1 animals. However, there were no intergroup differences in weight change or food intake. The weights and the food intakes of the 3 experimental groups were significantly lower than those of the control rats. No superiority in the results of blood samples was observed among the experimental groups. Correlations between weight gain and food intake were shown in all groups. But, a correlation between the volume of the gastric reservoir and food intake was observed only for group 3 rats. CONCLUSIONS: The present study showed no nutritional benefits of an iso- as well as an anti-peristaltic pouch replacement.

Animals↗

PubMed1978

[Pharmacokinetic study of antibiotics in human respiratory tract (author's transl)].

We report the results of the study of the bronchial concentrations of several antibiotics. The experiment included 280 patients and the concentrations achieved in bronchial secretions were measured for 11 antibiotics. The samples of bronchial secretions were taken in situ by fibroscopy or through the tracheostomy cannula. The results of the study show that the rate of penetration is variable according to the different drugs; even in the same antibiotic family such as beta-lactam antibiotics the rate of penetration is variable. The bronchial levels of aminoglycosides, macrolides and tetracyclines are worthwhile, and are often superior to the MIC of the infecting organisms; the penetration is also dependant of the inflammatory conditions of the bronchi. Otherwise the sampling conditions were the best possible since samples taken by fibroscopy or by tracheostomy are not contaminated by saliva which is a factor of dilutional error. The methodology used in this study is an approach of pharmacokinetics of antibiotics in respiratory tract.

Adult↗

PubMed2005

Capillary forces between two spheres with a fixed volume liquid bridge: theory and experiment.

Capillary forces are commonly encountered in nature because of the spontaneous condensation of liquid from surrounding vapor, leading to the formation of a liquid bridge. In most cases, the advent of capillary forces by condensation leads to undesirable events such as an increase in the strength of granules, which leads to flow problems and/or caking of powder samples. The prediction and control of the magnitude of capillary forces is necessary for eliminating or minimizing these undesirable events. The capillary force as a function of the separation distance, for a liquid bridge with a fixed volume in a sphere/plate geometry, was calculated using different expressions reported previously. These relationships were developed earlier, either on the basis of the total energy of two solid surfaces interacting through the liquid and the ambient vapor or by direct calculation of the force as a result of the differential gas pressure across the liquid bridge. It is shown that the results obtained using these methodologies (total energy or differential pressure) agree, confirming that a total-energy-based approach is applicable, despite the thermodynamic nonequilibrium conditions of a fixed volume bridge rupture process. On the basis of the formulas for the capillary force between a sphere and a plane surface, equations for the calculation of the capillary force between two spheres are derived in this study. Experimental measurements using an atomic force microscope (AFM) validate the formulas developed. The most common approach for transforming interaction force or energy from that of sphere/plate geometry to that of sphere/sphere geometry is the Derjaguin approximation. However, a comparison of the theoretical formulas derived in this study for the interaction of two spheres with those for sphere/plate geometry shows that the Derjaguin approximation is only valid at zero separation distance. This study attempts to explain the inapplicability of the Derjaguin approximation at larger separation distances. In particular, the area of a liquid bridge changes with the separation distance, H, and thereby does not permit the application of the "integral method," as used in the Derjaguin approximation.

Journal Article↗

PubMed2001

Bioavailability of PAHs in the Biobio river (Chile): MFO activity and biliary fluorescence in juvenile Oncorhynchus mykiss.

Cytochrome P450-dependent monooxygenase (MFO) activity and levels of bile PAH metabolites were measured in fish (Oncorhynchus mykiss) exposed to Biobio river (Chile) water. Experiments were performed simultaneously in both the field and laboratory to investigate whether the river water contained notable bioavailable PAH fractions. The field experiment was conducted using fish caged for 41 days at La Mochita (Biobio river mouth) whereas the laboratory experiment involved a 21-day exposure treatment with water collected in the same area. Induction of hepatic MFO, assayed by benzo(a)pyrene monooxygenase activity (BaPMO), and levels of PAH metabolites in the bile were measured in groups of eight (field experiment) and four specimens (laboratory experiment) sampled after 5, 10, 21 and 41 days of exposure. BaPMO was induced by a factor of 23 and 25 in fish caged for 21 and 41 days, respectively. Likewise, a significant BaPMO induction was found in the fish group experimentally exposed to river water for 21 days. Biliary fluorescence measurements, recorded by fixed wavelength fluorescence (FF) and synchronous fluorescence spectroscopy (SFS), revealed significantly high levels of PAH metabolites in bile samples of fish caged for 21 and 41 days. A positive relationship was found between BaPMO activity and biliary PAH metabolites. This study provides evidences that (i) Biobio river water contains a significant bioavailable PAH fraction in terms of marked effects on fish and (ii) the biological indicators MFO activity and bile PAH metabolites represent an excellent screening methodology to assess PAH exposure.

Animals↗

PubMed2000

Evaluation of extraction methods for recovery of fatty acids from lipid-producing microheterotrophs.

The effect of different extraction techniques on the recovery of fatty acids from freeze-dried biomass of two lipid-producing microheterotrophs was examined. Two procedures were used: the extraction of lipids from biomass followed by transesterification of the fatty acids (extraction-transesterification); and the direct transesterification of biomass to produce fatty acid methyl esters (i.e. without the initial extraction step). Variable factors in the extraction-transesterification experiment were the sequence in which solvents were added to the samples, the relative amount of methanol in the solvent mix, and sonication of biomass while in the solvent mix. Variable factors in the direct transesterification experiment were sample size, and reaction duration. Statistical analysis of data (level of significance P<0.05) showed that: (1) extraction of total fatty acids prior to transesterification was significantly more efficient when solvents were added in the order of increasing polarity; (2) neither sonication nor increasing the proportion of methanol in the extraction solvent significantly affected extraction of fatty acids prior to transesterification; (3) efficiency of direct transesterification of fatty acids increased significantly with reaction time; (4) efficiency of direct transesterification of fatty acids was not significantly affected by sample size; (5) the most efficient method for extraction of fatty acids prior to transesterification yielded significantly less fatty acids than the most effective direct transesterification method. While the study examined only two strains, our results suggest that fatty acid analysis methodology for microheterotrophs under consideration for biotechnological exploitation requires optimisation and validation.

Biomass↗

PubMed2005

An Italian program of external quality control for quantitative assays based on real-time PCR with Taq-Man probes.

Quantitative real-time PCR techniques are increasingly being used for the measurement of nucleic acids in research applications as well as in the clinical laboratory. It is therefore important that external quality control programs (EQA) are implemented for the evaluation of the analytical aspects common to molecular tests based on quantitative PCR. The aim of this study was the development of an Italian program of external quality control for quantitative assays based on real-time PCR with Taq-Mantrade mark probes to compare the analytical performance of 42 laboratories. Participants were provided with a set of reagents (cDNA for reference curve preparation, primers-probe mix and three unknown samples) and requested to perform a conventional assay using the master mix employed in their laboratories. The quantitative results in unknown samples were analyzed. The results of our study showed clear heterogeneity in performance. Two of the 42 laboratories provided results indicating contamination during the experiment, whereas six did not provide values for at least one of the six standard points. Only 12 laboratories gave results that were both precise and accurate for all the samples tested. Regarding imprecision, 17 laboratories appeared to deviate in at least one result, whereas inaccuracy showed an inverse dose-dependent trend. Finally, 12 laboratories were not able to measure the sample with the lowest concentration. Ten of these laboratories were equipped with the same instruments. The results of this first round of analytical EQA of real-time PCR-based methods seem to indicate high variability among laboratories carrying out the same experimental protocol. These findings could have implications for any assay based on this type of technique. This survey demonstrates the importance of experimental EQAs of methodological proficiency testing. Our approach has proved useful for comparing the analytical aspects shared by all diagnostic laboratories applying quantitative assays for the measurement of nucleic acids based on the use of Taq-Mantrade mark probes and real-time platforms.

Base Sequence↗

PubMedDate not supplied

Student nurses' experiences of Project 2000.

AIM: The aim of the study was to investigate student nurses' experiences of Project 2000. METHOD: A sample of 76 students completed a questionnaire twice, once at the beginning of the course and again after one year. A second questionnaire comprising rating scales of how stressed they felt, was completed by a sample of 30 students weekly for the first year of the course. RESULTS: Seven areas of concern were identified: the theory component of the course, assessments, clinical practice, financial pressures, time management, personal development and personal difficulties. CONCLUSION: Sufficient data were generated to suggest that the experiences of Project 2000 students in other institutions are likely to be similar to those reported in the study. Recommendations for teachers, clinical staff and students are made.

Adaptation, Psychological↗

PubMed2001

The menopausal symptom experience in young mid-life women with breast cancer.

Menopausal symptoms are important concerns for breast cancer survivors, which may influence daily activities, physical comfort and sexual health. Incidence and severity ratings of menopausal symptoms contribute to our knowledge about menopause in women with cancer, but fail to fully describe the symptom experience. The purpose of this article is to broaden our understanding by describing variation in menopausal symptom distress and how women interpret and manage symptoms within the context of breast cancer. From a larger grounded theory study that explored women's responses to the experience of premature induced menopause within the context of breast cancer, the constant comparative method of analysis was used to generate a detailed contextually grounded description of the menopausal symptom experience in a sample of 27 women with breast cancer who received adjuvant therapy. Women identified a symptom profile of menstrual cycle changes, hot flashes, insomnia, vaginal dryness, dyspareunia, alterations in mood, cognition and libido, and weight gain. The majority of women reported menopausal symptoms but some women were distress free while others reported moderate to severe distress. The context of breast cancer influenced women's response to symptoms and their decision making about menopausal symptom management.

Adaptation, Psychological↗

PubMed1992

[Quality assessment of ginseng by chemical fuzzy pattern recognition].

Water and liquor extracts of ginseng simulating its habitual preparations used in the practice of traditional Chinese medical science were prepared from 25 samples, and data reflecting its chemical constituents as a whole were obtained by ultraviolet and visible spectrophotometry (UV-Vis), high performance liquid chromatography (HPLC), and emission spectroscopy with inductively coupled plasma source (ICP). Antifatigue, antidiuretic, and macrophage phagocytosis experiments were carried out to determine the pharmacologic actions of the extracts. Results obtained with the extracts on mice were compared mutually and with those obtained on placebo-treated ones in the respective pharmacologic experiments. Based on the results of the three pharmacologic experiments, features were selected from among the chemical data and fuzzy equations formulated hereby were solved to ascertain the effective constituents with different weights and their compatibility. Finally, correlation analysis was carried out, and a new scheme for the quality assessment of ginseng has been worked out. The methodology proposed is of general significance to the formulation of quality assessment schemes for Chinese traditional medicines and the ascertainment of their bioactive constituents.

Animals↗

PubMed1998

The experience of nursing home life.

This study explored the articulate resident's experience of nursing home living. Using an ethnographic approach, data was collected through progressive, in-depth, open-ended interviews and participant observation from two 80-bed nursing homes in New South Wales. Employing purposeful sampling, eight key informants were selected concurrent with data collection and analysis according to the adequacy of information and appropriateness of subjects. Four major themes emerged from the data: (i) against my will, (ii) living in a public domain, (iii) cultural implications of living with others, and (iv) the impact of nursing home residency. Findings indicate that whilst some residents find the experience acceptable, for others the experience is both constraining and dehumanising.

Activities of Daily Living↗

PubMed2006

Prevalence of maltreatment of people with intellectual disabilities: a review of recently published research.

Maltreatment can have a profound adverse effect on the health of individuals with intellectual disabilities (ID). People with ID may also be more likely to experience maltreatment than other groups. Historically, data on prevalence of maltreatment among people with ID have been sparse and methodologically weak but have suggested that the scope of the problem is considerable. Studies published between 1995 and 2005 were reviewed to determine estimated maltreatment prevalence among people with ID based on recent literature. Prevalence estimates for people with ID were compared to estimates for people with no disabilities and people with other types of disabilities. Only five studies provided maltreatment prevalence estimates for people with ID. The limited data suggest that maltreatment is more prevalent for people with ID than for people with no disabilities and may be higher for people with ID than for people with certain other disabilities. Most of the available research is still based on convenience samples. More population-level data are needed to provide reliable estimates of the prevalence of this important health problem.

Adolescent↗

PubMed2004

Methodology of neuropsychological research in multicentre randomized clinical trials: a model derived from the International Subarachnoid Aneurysm Trial.

As advances in medicine and surgery lead to reductions in mortality rates for life-threatening conditions, it has become increasingly important to refine the methodology of auditing long-term morbidity. The inclusion of appropriate neuropsychological outcomes in a large multicentre randomized clinical trial poses considerable methodological and logistical difficulties. This paper presents a model developed to implement such a multicentre neuropsychological and quality of life audit for a subset of patients within the International Subarachnoid Aneurysm Trial (ISAT), the largest ever randomized trial in the treatment of subarachnoid haemorrhage. Based on our experience of collecting quality of life and neuropsychological outcomes from more than 550 patients, data are presented on the relative cost and efficacy of different organizational strategies, methods of canvassing patients and associated response rates. On the basis of this experience, we estimate a potential recruitment pool of 135 cases would be required to obtain some neuropsychological data on 100 cases. The design of any similar trial would therefore need to accommodate a loss to follow-up of approximately one third of the sample. In addition, our experience suggests that for a trial of this size and complexity, the deployment of centrally-based co-ordinators travelling to satellite centres is more cost-effective than employing co-ordinators based at those centres. Extrapolations from the observations and calculations reported here can be employed as an evidence base to inform the design of neuropsychological outcome studies in large multicentre trials.

Humans↗

PubMed2003

In vivo noninvasive measurement of blood glucose by near-infrared diffuse-reflectance spectroscopy.

This paper reports in situ noninvasive blood glucose monitoring by use of near-infrared (NIR) diffuse-reflectance spectroscopy. The NIR spectra of the human forearm were measured in vivo by using a pair of source and detector optical fibers separated by a distance of 0.65 mm on the skin surface. This optical geometry enables the selective measurement of dermis tissue spectra due to the skin's optical properties and reduces the interference noise arising from the stratum corneum. Oral glucose intake experiments were performed with six subjects (including a single subject with type I diabetes) whose NIR skin spectra were measured at the forearm. Partial least-squares regression (PLSR) analysis was carried out and calibration equations were obtained with each subject individually. Without exception among the six subjects, the regression coefficient vectors of their calibration models were similar to each other and had a positive peak at around 1600 nm, corresponding to the characteristic absorption peak of glucose. This result indicates that there is every possibility of glucose detection in skin tissue using our measurement system. We also found that there was a good correlation between the optically predicted values and the directly measured values of blood samples with individual subjects. The potential of noninvasive blood glucose monitoring using our methodology was demonstrated by the present study.

Adult↗

PubMed2005

Advanced oxidation protein products (AOPP) for monitoring oxidative stress in critically ill patients: a simple, fast and inexpensive automated technique.

Oxidative stress is known to be involved in many human pathological processes. Although there are numerous methods available for the assessment of oxidative stress, most of them are still not easily applicable in a routine clinical laboratory due to the complex methodology and/or lack of automation. In research into human oxidative stress, the simplification and automation of techniques represent a key issue from a laboratory point of view at present. In 1996 a novel oxidative stress biomarker, referred to as advanced oxidation protein products (AOPP), was detected in the plasma of chronic uremic patients. Here we describe in detail an automated version of the originally published microplate-based technique that we adapted for a Cobas Mira Plus clinical chemistry analyzer. AOPP reference values were measured in plasma samples from 266 apparently healthy volunteers (university students; 81 male and 185 female subjects) with a mean age of 21.3 years (range 18-33). Over a period of 18 months we determined AOPP concentrations in more than 300 patients in our department. Our experiences appear to demonstrate that this technique is especially suitable for monitoring oxidative stress in critically ill patients (sepsis, reperfusion injury, heart failure) even at daily intervals, since AOPP exhibited rapid responses in both directions. We believe that the well-established relationship between AOPP response and induced damage makes this simple, fast and inexpensive automated technique applicable in daily routine laboratory practice for assessing and monitoring oxidative stress in critically ill or other patients.

Adolescent↗

PubMedDate not supplied

Improvement of denitrification rates in confined zones of fractured subsoils under continuous wastewater injection.

An attempt to improve the natural biodegradation rate in a fractured aquifer (Nardò (Le), Southern Italy) subject since '91 to the injection of 12,000 m3/d of treated municipal wastewater, has been carried out through tests on pilot plants. The lab experiments showed that a complete nitrogen removal can be realized after 10 d of infiltration in fractures by adding whey in the influent waste. The lab results have been used in a mathematical model in order to simulate ground water quality changes caused by the addition of whey in the injecting water. The analytical parameters of ground water sampled in monitoring wells located at different distances from the injection site, have been compared with mathematical model results. Moreover for preserving such resource from pollution, the mathematical model allowed two areas, around the injection site to be drawn. These areas, where withdrawals would be prohibited, are required to avoid infections by pathogens and bacteria in ground water due to incomplete biodegradation processes. The experimental results can be useful to identify standardized methodology for artificial ground water recharge which could be required for aquifer clean up (Water Frame Directive 2000/60).

Fresh Water↗

PubMed2003

Stepping outside the stereotype. A pilot study of the motivations and experiences of males in the nursing profession.

Despite their historical significance to the UK's nursing profession, numbers of registered male nurses here have seldom exceeded 10% of the total. This is not an immutable principle, given that countries such as the Netherlands manage to attract males to the profession in much greater numbers. This paper examines and critiques the available literature on males in nursing from both a historical and present day perspective. In so doing, it discusses factors such as caring, over-performance and career progression, and, notions of masculinity. It then moves on to outline and discuss an on-going pilot study specifically designed to examine the motivations and experiences of a sample of preregistration and postregistration male nurses in the UK, across a range of ages and ethnicities. The ultimate aim of the study is to produce evidence which will advance the recruitment of men to a profession which is currently experiencing severe recruitment difficulties. The paper presents themes emerging from the study to date, examining the implications these may have for the future management of nurse recruitment.

Adaptation, Psychological↗

PubMed2001

Challenges mothers identify in bottle feeding their preterm infants.

PURPOSE: To describe the challenges mothers identify in bottle feeding their preterm infants prior to discharge from the NICU. DESIGN: Mothers bottle fed their infants in the NICU while being videotaped. Following the feeding, a semifocused interview was conducted with the mother using playback of the videotaped feeding to enhance exploration of the experience of feeding. SAMPLE: The participants were 22 mothers of preterm infants (< or = 1,500 grams). MAIN OUTCOME VARIABLE: Mothers' challenges in feeding preterm infants. RESULTS: Mothers identified three major categories of challenge: ensuring safety during the feeding, ensuring adequate intake of calories, and advancing the feeding plan once home. Mothers described strategies they used to meet these challenges and discussed the implications some of these strategies held for them.

Adaptation, Psychological↗

PubMed1992

Normal 24-hr ambulatory esophageal pH values. Influence of study center, pH electrode, age, and gender.

Although the most sensitive and specific test for diagnosing gastroesophageal reflux disease, normal standards for prolonged esophageal pH monitoring are based on small sample sizes with questions raised about the effects of pH electrode, older age, gender, and methods of data analysis on pH variables. Recently three groups have established normal data bases using similar methodology. Multiple regression and nonparametric analyses showed that the values for the six traditional pH parameters were comparable across study centers. Therefore, the groups were combined for a total study population of 110 healthy subjects (47 men, 63 women, mean age 38 years with a range of 20-84 years). Further nonparametric analyses revealed the following: (1) type of pH electrode (antimony vs glass) is not significantly related to parameters of physiologic acid reflux; (2) age is not independently related to pH parameters; (3) men tend to have more physiologic reflux than women; and (4) older men tend to experience longer episodes of reflux than younger men and women. There was a significant effect of gender and a significant interaction between age and gender on the number of episodes greater than 5 min (P = 0.008). Nearly significant differences were found for percentage of total acid exposure time (P = 0.03), total reflux episodes (P = 0.02), and the longest reflux episode (P = 0.02). We believe these normal esophageal pH values can be used confidently as standards in any laboratory, and consideration should be given to developing separate standards for men and women.

Adult↗