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PubMed2006

Impact of the availability of sonography in the acute gynecology unit.

OBJECTIVE: The initial assessment of acute gynecology patients is usually based on history and clinical examination and does not involve ultrasound. The aim of this study was to investigate the impact of the availability of transvaginal sonography at the time of initial assessment of the emergency gynecology patient. METHODS: This was a prospective observational study carried out over a 5-month period in the acute gynecology unit of an inner London teaching hospital. Women were assessed in the routine manner by history-taking and clinical examination and questionnaires were completed by the doctors, including details of the intention to treat. Transvaginal ultrasound examinations were then performed and a second diagnosis and management plan were made utilizing the extra information from the scan. The plans for clinical management before and after the ultrasound examination were compared. RESULTS: We originally recruited 1000 consecutive women to the study. The mean age was 31.1 (SD, 9.81) years. Complete data were available for 920 (92%). 84 (9.1%) women did not require a scan. Of the 521 women with a positive pregnancy test, 75.6% were reassured immediately that their pregnancy was intrauterine. 143 women (27.4%) were given the diagnosis of a suspected ectopic pregnancy before sonography, compared with 29 (5.6%) after. Following the ultrasound examination there was a change in clinical management in 54.1% of the women with a positive pregnancy test and a reduction in admissions (including inpatient theater admissions) (from 40.3% to 17.1%) and outpatient follow-up examinations (from 41.1% to 35.5%). In 90 (23.8%) non-pregnant women a significant ovarian cyst (> 5 cm) was suspected clinically; 28/90 (31.1%) were confirmed on sonography. Following the ultrasound examination there was a change in clinical management for 38.1% of non-pregnant women and a reduction in admissions (from 37.1% to 19.4%) and outpatient follow-up examinations (from 25.7% to 18.1%). CONCLUSION: It appears that the availability of transvaginal sonography at the time of initial assessment of emergency gynecology patients improves diagnostic accuracy and reduces unnecessary admissions and follow-up examinations.

Adolescent↗

PubMed1998

Cytokine production by human peripheral blood mononuclear cells: differential senstivity to glutamine availability.

Human peripheral blood mononuclear cells (PBMCs) were cultured in the presence of different glutamine concentrations (0, 0.1, 0.4, 0.6, 2 mM) and stimulated with concanavalin A (Con A) or bacterial lipopolysaccharide (LPS). The concentrations of T lymphocyte- and monocyte-derived cytokines were measured in the culture medium 24 h later. The availability of glutamine significantly increased the production of interleukin (IL)-2 (2-fold), IL-10 (4-fold) and interferon (IFN)-gamma (4.5-fold) by Con A-stimulated PBMCs. Maximal production of these cytokines occurred at 0.1 mM glutamine and increasing the concentration of glutamine above that did not lead to a further increase in cytokine production. Glutamine availability resulted in small increases (24 to 35%) in the production of IL-1alpha, IL-1beta, IL-6 and tumour necrosis factor (TNF)-alpha by Con A-stimulated PBMCs; again maximal production occurred at a glutamine concentration of 0.1 mM. Glutamine availability did not influence the production of IL-1beta or TNF-alpha by LPS-stimulated PBMCs, while there was a small increase (17 to 32%) in the production of IL-1alpha, IL-6 and IL-10 by these cells at a glutamine concentration of 0.1 mM. It is concluded that glutamine enhances the production of T lymphocyte-derived cytokines with only minimal effects on production of cytokines by monocytes.

Adult↗

PubMed1986

Nucleic acid staining with the methyl green-pyronin method. A comparison of the use of pure dyes and commercially available dyes.

We compared the staining obtained using commercially available pyronin Y samples with that obtained using pure pyronin Y in a standardized methyl green-pyronin procedure. In addition, the importance of the dye content of the anhydrous dye was investigated by varying the dye content by the addition of pure pyronin Y to one of the commercially available pyronin Y samples. We found that, for routine histological work, commercially available pyronin Y samples may produce acceptable results provided the sample can be shown by spectrophotometry to contain at least 43% pyronin Y.

Animals↗

PubMed1989

The effects of food and dose on the oral systemic availability of itraconazole in healthy subjects.

We have studied the influence of food and dose (50, 100, 200 mg) on the oral systemic availability of the broad spectrum antifungal itraconazole and the pharmacokinetics after repeated dosing of 100 mg in six healthy volunteers. The relative systemic availability of itraconazole capsules compared with solution averaged 39.8% in the fasting state but 102% in the post-prandial state. Food did not significantly affect the tmax of the capsules. Itraconazole AUC at single doses of 50, 100, and 200 mg had a ratio of 0.3:1:2.7, and the steady-state AUC (0-24) after 15 days of 100 mg was five times the single-dose AUC. These findings suggest non-linear itraconazole pharmacokinetics in the range of therapeutically used doses. Furthermore, capsules should be given shortly after a meal to ensure optimal oral systemic availability.

Administration, Oral↗

PubMed1980

Nomina dubia and available names.

The availability or non-availability of a name is a question of historical fact. A name once made available under the International Code of Zoological Nomenclature can be rendered unavailable only by use of the plenary powers of the Commission. The question whether a name is a nomen dubium or not is a matter of taxonomic judgement. The difficulty with the Sarcocystinae discussed by Frenkel et al. (1979) stems from the fact that, under the present provisions of the Code, it is not possible to designate for the species concerned types that will serve any useful function. The Commission is now considering changes to the Code proposed to remedy this defect in a general, legislative way. It will not, as a matter of general practice, entertain proposals for the suppression of names merely because they are considered to be nomina dubia. The application submitted by Professor Frenkel and his collegaues will nevertheless be published in the Bulletin of Zoological Nomenclature so that the Commission can, if necessary, deliver a ruling on it before the new edition of the Code has appeared.

Animals↗

PubMed1987

Hospital ownership and psychiatric services. Implications of ownership and reimbursement changes on lengths of stay and availability of services.

Dramatic increases have occurred in the proportion of for-profit hospitals in the general hospital sector; even more pronounced increases have occurred within the psychiatric sector. Concomitant with this changing mix of ownerships, revised reimbursement plans are being proposed for psychiatry. Thus, providers of acute psychiatric inpatient care, although loosely aggregated, constitute a service system that is experiencing dynamic revision. This article examines the implications of these changes for health policy analysts and planners in the design of hospital payment mechanisms and in planning for resources to meet the needs of the public. The state of California is viewed as a system, and data from the state are examined to test traditional assumptions of economic behavior when less costly substitute services are available. The availability of services such as outpatient clinics, emergency psychiatric services, and partial hospitalization are found to vary according to hospital ownership. Differences in availability of these services influence the access to inpatient care experienced by various populations within the defined system. Although these services may permit earlier discharge from the hospital, the poor insurance coverage of ambulatory psychiatric care relative to inpatient hospitalization distorts this effect. The implications of these findings for public policy are discussed.

California↗

PubMed1992

The assessment of cellular proliferation by immunohistochemistry: a review of currently available methods and their applications.

Immunohistochemical methods using antibodies to cell cycle-related antigens may be used as a means of assessing various aspects of proliferation in tissue, and have the important advantage of preserving the spatial orientation of proliferating cells in histological sections. Currently, the most widely available antibodies for this purpose are antibodies to bromodeoxyuridine (BrdU), Ki67 and antibodies to proliferating cell nuclear antigen (PCNA). BrdU is a thymidine analogue incorporated during the S phase of the cell cycle, which can be introduced by 'in vitro' incubation, and monoclonal antibodies are available to display its localization. Ki67 demonstrates a nuclear antigen expressed in all phases of the cell cycle, except G0 and early G1, but can only be applied to frozen tissue. PCNA is a nuclear antigen which is essential for DNA synthesis, two commercially available antibodies to PCNA work in paraffin-embedded tissue, but may have different staining characteristics under different conditions of fixation. The main advantages and disadvantages of these different techniques are discussed, together with their main applications to date.

Antibodies, Monoclonal↗

PubMed1989

Rat bioassays for methionine availability in 16 food sources.

Methionine availabilities of 16 test proteins were assessed by comparing ten day rat growth response to the test diets and reference (casein) diets. In a preliminary study, various concentrations of methionine and cystine were fed to determine methionine requirements and effect of excess cystine. Results indicated a methionine requirement of about 550 mg per 100 g diet. Cystine had a sparing affect of 50-55%, i.e., about 300 mg could be used to meet methionine requirements. Further additions of cystine (up to 2.6 times methionine) did not affect rat growth. Methionine availabilities were excellent (88-100%) for 15 of the 16 test foods; only pinto beans (58%) were low, but prior evidence indicates that the poor growth response was due to some factor other than availability.

Animals↗

PubMed1985

Effect of proteins on availability of zinc. I. Gastrointestinal transit time of casein and whey protein and zinc absorption in weaned rats.

The availability of zinc from isolated casein (CasD) was compared with that from whey protein (WpD) in 23-25 day old rats. The study was designed to show the course of the gastrointestinal transit time of either chyme (radiolabeled by 141Ce as a non-absorbable marker) or zinc (as 65Zn) in groups of 9 to 12 animals each. Animals were killed either 1/4, 1/2, 1, 2, 6, 12 or 24 hours after intragastric intubation of the protein suspensions. Immediately afterwards, intragastric pH was measured and the determination of zinc retention in intestinal tissues and liver as well as in the carcass was performed. 30 and 60 minutes after intubation the intragastric pH of the CasD group was significantly lower than that of the WpD group. The precipitation behaviour of the two protein fractions - compact curd formation by the CasD versus flocculent structure of the WpD - was determining for the pattern of gastric emptying. With the WpD the chyme was emptied according to an exponential function; while the CasD precipitate left the stomach in three distinct phases. With either protein suspension zinc left the stomach ealier than the bulk of the chyme, indicating a partial disintegration of the zinc-protein-complexes. With the WpD, zinc was emptied exponentially, whereas with the CasD a biphasic emptying pattern was found. Ileum was found to be the main zinc absorbing segment, mainly due to the long time of contact with zinc. After 2 and 12 hours zinc retention from the CasD was significantly higher than that from the WpD, however, after 24 hours retention was significantly better from the WpD. From the present study it can be concluded that, for comparison of zinc availability from diets containing different proteins, short-term experiments are not appropriate. Furthermore, it can be supposed that preabsorptive processes in the stomach are crucial for the availability of zinc.

Animals↗

PubMed1992

Behavioral economics of drug self-administration. IV. The effects of response requirement on the consumption of and interaction between concurrently available coffee and cigarettes.

In behavioral economics, consumption of a reinforcer is determined by its price and by the price of other available reinforcers. This study examined the effects of price manipulations on the consumption of concurrently available coffee and cigarettes. During fifteen 4-h sessions, coffee and cigarettes were concurrently available according to fixed-ratio (FR) schedules of reinforcement. After consumption stabilized under a fixed ratio 100 for both reinforcers, the response requirement for each reinforcer was varied separately (i.e., FR 100, 1000 and 2500), while the response requirement for the other reinforcer was kept at 100. Increasing the FR value decreased coffee and cigarette consumption to a similar degree. Also, as the price for cigarettes increased (and consumption decreased), coffee consumption decreased; however, as the price of coffee increased, cigarette consumption did not change. These results indicate that for this setting the reinforcing effects of cigarettes and coffee were comparable but interacted asymmetrically. These findings when analyzed and quantified via economic concepts of own-price and cross-price elasticity illustrate the viability of using behavioral economics to examine drug self-administration in a choice paradigm.

Adolescent↗

PubMed1980

Correlation between cell density, membrane fluidity, and the availability of transferrin receptors in Friend erythroleukemic cells.

Undifferentiated Friend erythroleukemic cells (FL-cells) acquire membrane microviscosity (eta), in accord with the culture cell density. At low cell density eta (21 degrees) approximately 2.8 poise, whereas at confluency it increases to eta (21 degrees) approximately 5.3 poise. Concomitantly, the total number of available transferring receptors per cell decreases by about 80% upon increase in cell density. Modulation of membrane microviscosity, by artificial alteration of the membrane cholesterol level, mediates similar modulations of the availability of the transferrin receptors. The correlation between the availability of the transferring receptors and the membrane lipid fluidity may take part in the overt decrease in iron uptake by erythroid cells along the erythropoiesis pathway.

Animals↗

PubMed1991

Contraceptive use in young women: uptake, availability and education.

Despite increased availability of contraception and a relaxation of prescribing laws unplanned pregnancies will still occur. However when the right to life of the unborn child is enshrined in the constitution it is vital to provide adequate sex education and ensure the availability of all methods of contraception to reduce unplanned pregnancies to a minimum. This paper surveys the use of contraception prior to pregnancy in a group of unmarried mothers who delivered at a Dublin maternity hospital. It also surveys the availability of contraception from the pharmacies within the hospital's catchment area and the provision of sex education in the surrounding schools.

Adult↗

PubMed2000

Method availability and the prevention of suicide--a re-analysis of secular trends in England and Wales 1950-1975.

BACKGROUND: In England and Wales in the 1960s there were marked declines in suicide rates. These reductions were partly attributable to the detoxification of the domestic gas supplies; however, their extent varied by age and gender, with the most striking effects seen in older men. The objective of this study was to investigate method-specific trends in suicide between 1950 and 1975 to elucidate possible explanations for the patterns seen in different demographic groups. METHODS: An analysis of age-standardised method-specific suicide rates for England and Wales between 1950 and 1975 was carried out using routinely available mortality and population statistics. RESULTS: As has previously been shown, there were marked reductions in suicides by gassing in men and women of all ages between 1960 and 1975. In women and younger men, the effects of these reductions on overall suicide rates were partially offset by rises in drug overdose deaths (method substitution), but there were no immediate increases in the use of other suicide methods. In contrast, in older men, reductions in suicide by gassing were accompanied by only a slight increase in overdose suicides as well as reductions in rates of suicide using all other methods. The modest rise in overdose fatalities in older men occurred despite the fact that they were more often prescribed barbiturates and tricyclic antidepressants than younger men. CONCLUSIONS: Accessibility to and the lethality of particular methods of suicide may have profound effects on overall suicide rates. Such effects appear to depend upon the popularity of the method and the extent to which alternative methods that are acceptable to the individual are available. Social and psychological interpretations of fluctuations in suicide rates should only be made after assessing the possible contribution to these of changes in method availability and lethality.

Adolescent↗

PubMed2006

Serotonin 1A receptor availability in patients with schizophrenia and schizo-affective disorder: a positron emission tomography imaging study with [11C]WAY 100635.

BACKGROUND: Postmortem and positron emission tomography (PET) studies have reported several alterations in serotonin 1A receptor (5-HT(1A)) binding parameters in patients with schizophrenia. This study examines 5-HT(1A) availability in vivo in individuals with schizophrenia and schizo-affective disorder. MATERIALS AND METHODS: Twenty-two medication-free individuals with schizophrenia or schizo-affective disorder and 18 healthy subjects underwent PET scans with [(11)C]WAY 100635. Regional distribution volumes (V(T), in milliliters per gram) were derived using a two-tissue compartment kinetic model. Outcome measures for 5-HT(1A) availability included binding potential (BP) and the specific to nonspecific equilibrium partition coefficient (V(3)''). Eleven brain regions with high density of 5-HT(1A) were included in the analysis. RESULTS: No significant differences were observed in regional BP or V(3)'' between patients and controls. No significant relationships were observed between regional 5-HT(1A) availability and symptom severity. CONCLUSION: The postmortem literature reports increased 5-HT(1A) binding in the prefrontal cortex in schizophrenia. This study did not detect differences in 5-HT(1A) binding. Whereas in two recently published PET studies, one reports increased binding in the temporal lobe while the other reports decreased binding in the amygdala. These inconsistencies suggest that the alterations demonstrated in postmortem studies cannot be reliably detected at the resolution achieved with PET. This raises the question as to whether major changes in the level of expression of the 5-HT(1A) receptor play a role in the pathophysiology of schizophrenia.

Adult↗

PubMed2004

Soil water content and organic carbon availability are major determinants of soil microbial community composition.

Exploration of environmental factors governing soil microbial community composition is long overdue and now possible with improved methods for characterizing microbial communities. Previously, we observed that rice soil microbial communities were distinctly different from tomato soil microbial communities, despite management and seasonal variations within soil type. Potential contributing factors included types and amounts of organic inputs, organic carbon content, and timing and amounts of water inputs. Of these, both soil water content and organic carbon availability were highly correlated with observed differences in composition. We examined how organic carbon amendment (compost, vetch, or no amendment) and water additions (from air dry to flooded) affect microbial community composition. Using canonical correspondence analysis of phospholipid fatty acid data, we determined flooded, carbon-amended (+C) microcosm samples were distinctly different from other +C samples and unamended (-C) samples. Although flooding without organic carbon addition influenced composition some, organic carbon addition was necessary to substantially alter community composition. Organic carbon availability had the same general effects on microbial communities regardless of whether it was compost or vetch in origin. In addition, flooded samples, regardless of organic carbon inputs, had significantly lower ratios of fungal to bacterial biomarkers, whereas under drier conditions and increased organic carbon availability the microbial communities had higher proportions of fungal biomass. When comparing field and microcosm soil, flooded +C microcosm samples were most similar to field-collected rice soil, whereas all other treatments were more similar to field-collected tomato soil. Overall, manipulating water and carbon content selected for microbial communities similar to those observed when the same factors were manipulated at the field scale.

Agriculture↗

PubMed2006

A cybernetic model to predict the effect of freely available nitrogen substrate on rifamycin B production in complex media.

It is well-known that secondary metabolite production is repressed by excess nitrogen substrate available in the fermentation media. Although the nitrogen catabolite repression has been known, quantitative process models have not been reported to represent this phenomenon in complex medium. In this paper, we present a cybernetic model for rifamycin B production via Amycolatopsis mediterranei S699 in complex medium, which is typically used in industry. Nitrogen substrate is assumed to be present in two forms in the medium; available nitrogen (S(ANS)) such as free amino acids and unavailable nitrogen (S(UNS)) such as peptides and proteins. The model assumes that an inducible enzyme catalyzes the conversion of S(UNS) to S(ANS). Although S(ANS) is required for growth and product formation, high concentrations were found to inhibit rifamycin production. To experimentally validate the model, five different organic nitrogen sources were used that differ in the ratio of S(ANS)/S (UNS). The model successfully predicts higher rifamycin B productivity for nitrogen sources that contain lower initial S(ANS). The higher productivity is attributed to the sustained availability of S(ANS) at low concentration via conversion of S(UNS) to S(ANS), thereby minimizing the effects of nitrogen catabolite repression on rifamycin production. The model can have applications in model-based optimization of substrate feeding recipe and in monitoring and control of fed batch processes.

Actinomycetales↗

PubMed2007

Adjusting energy expenditures to energy supply: food availability regulates torpor use and organ size in the Chilean mouse-opossum Thylamys elegans.

We studied how food abundance and consumption regulates torpor use and internal organ size in the Chilean mouse-opossum Thylamys elegans (Dielphidae), a small nocturnal marsupial, endemic in southern South America. We predicted that exposure to food rations at or above the minimum energy levels necessary for maintenance would not lead to any signs of torpor, while reducing food supply to energy levels below maintenance would lead to marked increases in frequency, duration and depth of torpor bouts. We also analyzed the relationship between food availability and internal organ mass. We predicted a positive relationship between food availability and internal organ size once the effect of body size is removed. Animals were randomly assigned to one of two groups and fed either 70, 100 or 130% of their daily energy requirement (DER). We found a positive and significant correlation between %DER and body temperature, and also between %DER and minimum body temperature. In contrast, for torpor frequency, duration and depth, we found a significant negative correlation with %DER. Finally, we found a significant positive correlation between the %DER and small intestine and ceacum dry mass. We demonstrate that when food availability is limited, T. elegans has the capacity to reduce their maintenance cost by two different mechanisms, that is, increasing the use of torpor and reducing organ mass.

Adaptation, Physiological↗

PubMed2004

Reduced serotonin transporter-availability in obsessive-compulsive disorder (OCD).

We investigated the availability of brain serotonin transporters in 10 drug-free patients with obsessive-compulsive disorder (OCD) and age-matched healthy controls in vivo using single-photon emission computed tomography (SPECT) and the radioligand [(123)I]-2beta-carbomethoxy-3beta-(4-idiophenyl)-tropane ([(123)I]beta-CIT). For quantification of regional serotonin transporter a ratio of specific to non-specific [(123)I]beta-CIT-binding was used. The availability of serotonin transporter was calculated using regions of interests (ROI) for thalamus/hypothalamus, midbrain, brainstem (highest density of serotonin transporter) and cerebellum as a reference. The mean specific to non-specific [(123)I]beta-CIT binding ratios in the thalamic/hypothalamic ROI were 4.95 +/- 0.57 (OCD patients), and 5.48 +/- 0.87 (control group). The mean ratios in the midbrain ROI were 3.51 +/- 0.45 (OCD patients) and 4.89 +/- 1.23 (controls) and in the brainstem ROI the ratios were 2.38 +/- 0.76 (OCD patients) and 3.53 +/- 1.01 (controls). This in vivo finding of significant reduced serotonin transporter availability in midbrain/brainstem using [(123)I] beta-CIT SPECT further supports the serotonin deficit hypothesis of OCD.

Adult↗