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PubMed1984

Available biotin content of various feed ingredients.

The availability to the chick of the microbiologically determined biotin in various feed ingredients was assayed using a standard curve methodology. The chicks were grown up to 28 days of age. Ingredients of the standard diet were partially replaced by the test ingredient. Each test mixture was also supplemented with 200 micrograms biotin/kg and fed to a control group. The percentage of growth of the test chicks compared with the controls proved to be a suitable parameter for the assessment of biotin availability. Availability of biotin was expressed in percentage of the biotin determined microbiologically. In the tested cereals availability was distinctly low, whereas in some other feed ingredients the availability was reduced less.

Animal Feed↗

PubMed1992

Effect of overcooked soybean meal on chicken performance and amino acid availability.

Studies were conducted to evaluate the effect of overcooked soybean meals (SBM) on chick growth and amino acid availability. The SBM were custom-prepared at a commercial processing plant by changing the conditions of a desolventizer-toaster (DT) unit. Six progressively overcooked meals (designated SBM1 to 6 with SBM1 as normal, and SBM6 overcooked) were produced by increasing temperature by up to 50% and extending retention time by up to 75% above normal. The meals measured .05, .03, .01, .09, .00, and .00 delta pH of urease activity; 6.10, 5.01, 4.62, 4.83, 2.32, and 1.78 mg/g SBM of trypsin inhibitor activity; 92, 89, 91, 88, 81, and 81% of protein solubility in .2% KOH; and 46, 43, 41, 40, 23, and 19% of protein solubility in .1 M borate at 40 C, respectively. Glucose content in the hydrolysate of the soluble carbohydrate extract did not differ among the meals, indicating no differences in the degradation of sucrose, raffinose, and stachyose with increasing heat treatment. In a chick growth experiment with a methionine-adequate, low-protein diet, chicks fed SBM1 showed significantly greater weight gain than chicks fed SBM3, 5, or 6. The SBM1, 2, 5, and 6 were chosen for a study of amino acid availability. No differences were observed in amino acid content. There were significant differences in apparent amino acid availability to growing chicks, but not in true amino acid availability by adult roosters among the four meals. The results suggest that the temperature or the retention time of a DT unit may be increased by 50% over the usual operating conditions without reducing amino acid availability from SBM.

Amino Acids↗

PubMed2002

Effect of traditional fermentation and malting on phytic acid and mineral availability from sorghum (Sorghum bicolor) and finger millet (Eleusine coracana) grain varieties grown in Kenya.

Sorghum and finger millet grains are traditional staple foods in Kenya. However, they have naturally occurring anti-nutritional factors, such as phytic acid, that decrease their dietary availability. This work determined the effect of fermentation and malting on the phytic acid content of, and mineral availability in five varieties of sorghum and four varieties of finger millet grain grown in Kenya. Phytic acid ranged from 875.1 to 2,211.9 mg/100 g in sorghum. The levels in finger millet ranged from 851.6 to 1,419.4 mg/100 g grain. Fermentation resulted in a mean decrease of phytic acid in of 64.8% after 96 hours and 39.0% after 72 hours in sorghum grain. In finger millet, there was a mean decrease of 72.3% and 54.3% after 96 and 72 hours, respectively. Malting also resulted in a mean decrease of 23.9 and 45.3% after 72 and 96 hours, respectively. The extent of decrease of phytic acid differed among the grain varieties. Fermentation increased the rate of available iron, manganese, and calcium in both sorghum and finger millet. The available minerals were generally higher in finger millet than in sorghum after fermentation. Fermentation was also more effective than malting in reducing phytic acid in sorghum and finger millet. Simple traditional food processing methods can therefore be used to increase mineral availability.

Biological Availability↗

PubMedDate not supplied

Available amino acid score for evaluating protein quality of foods.

Amino acid scores corrected for true digestibility of individual amino acids (as determined by rat balance method) were termed "available amino acid scores" in the present investigation. Available amino acid scores were calculated for 7 protein sources and their 10 supplementary or complementary mixtures which have been tested in collaborative amino acid and rat growth assays for evaluating protein quality. The available amino acid scores were as follows: casein + methionine (100); egg white (100); rapeseed protein concentrate, RPC (94); casein (93); beef (89); soya assay protein, SAP (62); pea flour (61); whole wheat flour, WW (38); SAP + methionine (88); pea flour + methionine (72); WW + lysine (67); WW + casein (84); WW + egg white (79); WW + RPC (65); WW + beef (77); WW + SAP (70); and WW + pea flour (75). These scores were similar to the collaborative relative NPR values; the differences were less than 10 units (2-9 units) in most cases. The positive correlation (r = 0.92) between available amino acid scores and relative net protein ratio (RNPR, a rat growth method) values was highly significant (P less than 0.01) and the origin of the regression line (y = 0.92x + 1.88) was not significantly different from zero. Amino acid bioavailability has previously been a problem, preventing widespread acceptance of amino acid score. Available amino acid score solves this problem.

Amino Acids↗

PubMed1993

[Distribution of phospholipids in platelet membranes and platelet factor 3 availability in patients with chronic kidney failure].

Patients with end-stage renal failure (ESRF) have a defect of haemostasis mainly caused by disturbances of platelet vessel wall interactions. An essential part in platelet function is played by the membrane phospholipids. The aim of this study was to estimate phospholipid distribution in platelet membrane and to evaluate the correlation between this distribution and PF3 availability. 18 non-dialysed (group I) and 21 chronically haemodialysed patients (group II) were studied. Phospholipid distribution was determined using TNBS tracer by the Vale method, and by phospholipase hydrolysis according to the modified Chap method. PF3 availability was estimated by the Saleem method. In group I membrane phospholipid distribution was unchanged as compared with control group, in this group decreased PF3 availability was also shown. In group II higher content of phosphatidylserine (PS) and phosphatidylethanolamine (PE) at the outer surface of platelet membrane was observed as compared with the healthy persons. In this group increased PF3 availability correlated with PS and PE exposition was also noted. It may reflects platelet activation in these patients. The different PF3 availability in non-dialysed and chronically haemodialysed patients suggests various pathogenesis of haemostasis disturbances in their patients.

Adult↗

PubMed1994

Fluoride and potassium availability in a new dentifrice that treats hypersensitivity and controls tartar.

The availability and stability of the active ingredients in a Sensitive/Tartar Control dentifrice have been evaluated in this study. The Sensitive/Tartar Control dentifrice contains 5% potassium nitrate as the anti-hypersensitivity agent, 0.243% sodium fluoride as the anti-caries agent, 2% tetrasodium pyrophosphate and 1.5% polyvinylmethyl ether/maleic acid (PVM/MA) copolymer as the antitartar system. The availability of potassium and fluoride from this dentifrice was tested and found to be acceptable in both freshly prepared and aged samples. Fluoride and potassium availability were also tested at dilutions similar to in vivo brushing levels, and the ability of the Sensitive/Tartar Control dentifrice to provide fluoride to enamel and reduce enamel solubility was measured. In these tests the Sensitive/Tartar Control dentifrice performed similarly to commercial fluoride dentifrices. Potassium availability was equal to Crest Sensitivity Protection, a product shown to be clinically effective against tooth sensitivity; fluoride availability and activity was shown to be equal to Crest Tartar Control, a product with published clinical anti-caries effectiveness.

Analysis of Variance↗

PubMed2006

Seasonal variation of diet and food availability in a group of Sichuan snub-nosed monkeys in Shennongjia Nature Reserve, China.

We studied the diet and food availability of a group of Sichuan snub-nosed monkeys for 14 months (July 2003 to September 2004, except for February) in the Shennongjia Nature Reserve, China. This species is primarily a lichen eater, with lichens (Usneaceae) accounting for 43.28% of feeding records (n=3,452). Other food types in the diet were young leaves (28.71%), fruits or seeds (14.57%), buds (5.36%), mature leaves (3.51%), herbs (2.09%), bark (1.36%), and flowers (1.13%). The monkeys used 23 plant species. Their diet showed a complicated seasonal variation: the monthly diet varied from primarily lichens in November-April, to a mixture of leaves and lichens in May-July, to a mixture of fruits or seeds and lichens in August-October (the latter depended on annual fruit and seed availability). The proportion of fruits or seeds in the diet was negatively correlated with that of lichens, which suggests that the monkeys prefer fruits or seeds to lichens when all of these items are available. The fruit or seed availability varied greatly between the two study years. The proportion of lichens, young leaves, flowers, and fruits or seeds in the diet was positively associated with their availability. The monkeys appeared to be selective feeders. They preferred 10 tree species for plant parts, and nine tree species for lichens. The selection index of tree species for lichens was positively related to lichen coverage per branch on tree species, demonstrating that the monkeys preferred tree species with abundant lichens, as well as dead trees for lichens. The results suggest that dead-tree harvesting in the reserve could significantly reduce the quality of habitat for these monkeys, and should therefore be prohibited. Connus controversa, Cerasus discadenia, Salix willichiana, and Malus halliana should be conserved as top priority species because the monkeys preferred them for both their vegetative parts and the lichens that grow on them.

Animal Nutritional Physiological Phenomena↗

PubMed2002

Unrestricted availability of intracoronary stents is associated with decreased abrupt vascular closure rates and improved early clinical outcomes.

The purpose of this study was to determine whether the unrestricted availability of intracoronary stents is affecting abrupt vascular closure rates and early clinical outcomes. Intracoronary stents have improved procedural outcome despite their application in more complex lesions, but the impact of unrestricted availability of stents on abrupt closure and early clinical outcomes is unknown. Two cohorts were identified retrospectively from a coronary intervention registry: patients treated between 1988 and 1992 (n = 3,617) when stents were not generally available, and patients treated between 1994 and 1997 (n = 4,518) when stents were freely available. The late cohort patients consisted of more females; it also had greater comorbidity and more complex presentation. However, there was a significant reduction in the abrupt closure rates between the two time periods (7% vs. 4%, P < 0.0001). After adjusting for female gender, thrombus, and lesion angulation, the late cohort remained significantly associated with decreased odds of abrupt closure (odds ratio [OR] = 0.62, 95% upper and lower confidence intervals [CI] = 0.52-0.75, P = 0.0001). The late cohort also had decreased in-hospital mortality (OR = 0.91, CI = 0.86-0.95, P = 0.0002) and major adverse clinical event (OR = 0.93, CI = 0.91-0.96, P = 0.0001). Unrestricted availability of intracoronary stents is associated with reduced abrupt closure rates and improved early clinical outcomes among patients undergoing coronary intervention despite treatment of high-risk patients.

Acute Disease↗

PubMed2002

Melphalan availability in hypoxia-inducible factor-1alpha+/+ and factor-1alpha-/- tumors is independent of tumor vessel density and correlates with melphalan erythrocyte transport.

Many tumors are impervious to anticancer agents. Resistance due to lack of cytotoxic penetration into the tumor is often overlooked but can play a significant role in undermining therapy. Insufficient and irregular vascularization of tumors is a possible barrier to drug delivery, but there are others, e.g., impaired vessel permeability and poor interstitial transport. We evaluated the importance of tumor vessel density in the availability of melphalan to tumors. A nude mouse tumor model with different vascularization due to a single-gene deletion of hypoxia-inducible factor 1alpha (HIF-1alpha(+/+) and HIF-1alpha(-/-) embryonic stem cell-derived tumors) was used. The availability of melphalan to HIF-1alpha(+/+) (n = 20) and HIF-1alpha(-/-) (n = 23) tumors was not significantly different (p = 0.12). Furthermore, in the various subgroup analyses accentuating the difference in vessel density, no significant correlation between vessel density and melphalan availability was found. In the second part of the study, melphalan, was demonstrated to be transported in blood in mice with a distribution of 24% in erythrocytes vs. 76% in plasma. A strong correlation (r = 0.93, p < 0.000001) between melphalan concentrations in plasma and erythrocytes was found, indicating an equilibrium between these 2 compartments. Plasma and erythrocyte concentrations of melphalan are correlated with the tumor availability of melphalan (r = 0.66 and 0.64, respectively, both p < 0.001). These data suggest that tumor vessel density is not an important predictor of the tumor availability of small cytotoxic drugs such as melphalan and indicate the importance of erythrocytes in the transport of melphalan.

Animals↗

PubMed2005

The relationship between available support, unmet needs and caregiver burden in patients with advanced cancer and their carers.

Caregiver burden is an increasing problem with patients surviving longer and more care tasks falling to informal caregivers. While research has identified patient and caregiver variables associated with caregiver burden, less research has focused on aspects of the care environment. The present study investigated the available support and unmet needs of 57 patients with advanced cancer, 45 of their carers and 40 of their health professionals. Carers and patients consistently identified higher levels of available support for the patient than health care professionals, with carers identifying higher levels of support than patients. Carers also identified more patient unmet needs than health care professionals, who in turn identified more than patients. Surprisingly, available support did not increase over 6 months and there was a tendency for unmet needs to decrease over time. Low available support, high unmet needs and a larger discrepancy between carer and patients' reports of patients' unmet need predicted negative aspects of caregiver burden. These results suggest that health care professionals underestimate available support to patients and both patients and health care professionals underestimate patients' unmet needs in comparison to carers. Carers' reports of patients' unmet needs are important to consider as they were associated with high levels of caregiver burden, including poorer caregiver health. Health care professionals should encourage opportunities for carers to discuss their views of the ongoing needs of patients with advanced cancer.

Aged↗

PubMed1983

The role of alcohol availability in alcohol consumption and alcohol problems.

The major theoretical approaches that have provided competing explanations for the distribution and nature of alcohol problems are reviewed and assessed. The sociocultural model and studies are briefly discussed with major emphasis given to the particular studies that have focused on different conceptions and dimensions of availability. Attempts to integrate the sociocultural model and the distribution of consumption model are also reviewed. A recent integrated model finds specific relationships between physical availability or the different types of outlets, with social area characteristics of different populations, and some four different alcohol problems, including cirrhosis, public drunk arrests, and misdemeanor and felony drunk driving arrests. Specific social area characteristics representing social class, minority status, and other structural features such as unemployment and women's labor force participation become implicated in alcohol problems independently of the effects of differing levels of availability. Additional related research on licensing and enforcement practices, beliefs, and attitudes of ABC personnel are also reviewed in relation to the general issue of availability. Other recent research on social and psychological dimensions of availability are also reviewed. Cross-sectional time series modeling is suggested as a technique for determining causal processes.

Alcohol Drinking↗

PubMedDate not supplied

The relationship between school characteristics and the availability of mental health and related health services in middle and high schools in the United States.

Problems related to mental illness are increasingly becoming the focal point of public concern over the safety and performance of schools, yet little is known about the availability and quality of school-based mental health services in the United States. In this article it is estimated that approximately 50% of US middle and high schools have any mental health counseling services available onsite and approximately 11% have mental health counseling, physical examinations, and substance abuse counseling available on-site. There are substantial differences in mental health counseling availability by region, urbanicity, and school size, with rural schools, schools in the Midwest and South regions, and small schools being least likely to offer mental health counseling. Multivariate estimates suggest that disparities between schools in the availability of mental health counseling and related health services may be partly explained by differences in access to Medicaid for financing of health services provided at school.

Adolescent↗

PubMed1999

Effects of vascular or luminal administration and of simultaneous glucose availability on glutamine utilization by isolated rat small intestine.

This study examined whether the route of glutamine administration and the simultaneous availability of glucose affect intestinal glutamine metabolism. We measured net substrate exchange rates of glutamine and its nitrogenous products in the isolated vascularly and luminally perfused rat small intestine (a) as a function of glutamine provision from either the vascular or the luminal or simultaneously from both sides and (b) as a function of simultaneous availability of glucose from various routes. When glutamine was provided from the lumen, only 19-32% of absorbed glutamine appeared intact in the venous effluent, but the release of metabolic products was 170 +/- 5 nmol N min-1 g-1. This measure of intestinal glutamine metabolism was unchanged when glutamine was available only in the vascular perfusate (164 +/- 6 nmol N min-1 g-1). It increased, however, to 271 +/- 14 nmol N min-1 g-1 (P < 0.001) when glutamine was available simultaneously from both the luminal and the vascular perfusate. Glutamine consumption (-110 +/- 6 vs. -70 +/- 5 or -91 +/- 5 vs. -73 +/- 7 nmol min-1 g-1; P < 0.05 each) and the production of citrulline (11.4 +/- 0.7 vs. 10.0 +/- 0.8 or 9.8 +/- 0.5 vs. 7.8 +/- 0.4 nmol min-1 g-1; P < 0.05 each) or ammonia (124 +/- 7 vs. 88 +/- 4; P < 0.01 or 78 +/- 4 vs. 68 +/- 5 nmol min-1 g-1) decreased when glucose (vascular or luminal perfusate) became available in addition to glutamine. We conclude that glutamine is utilized by the small intestine very efficiently regardless of the route of administration being enteral or parenteral. The two routes can be used interchangeably to provide the intestinal mucosa with glutamine. Glucose and glutamine may partially substitute each other, most likely for the purpose as a metabolic fuel.

Ammonia↗

PubMed1997

Sodium nitroprusside and cGMP decrease Ca2+ channel availability in basilar artery smooth muscle cells.

We studied the effect of the nitric oxide (NO) donor, sodium nitroprusside (SNP), on the macroscopic and single-channel currents due to the 22-pS Ca2+ channel in smooth muscle cells from guinea pig basilar artery. In nystatin-perforated whole-cell recordings, 50 nM SNP decreased the macroscopic current to 63+/-12% of control values, without changing the voltage dependence of the current. In cell-attached patches with BAY-K8644 in the pipette, SNP caused a comparable decrease in single-channel availability (n . Po) that was dose dependent over the range of 10 nM to 10 microM SNP. SNP had no effect on single-channel properties, including slope conductance, voltage dependence of activation, the number of open states, the time constants of the open states, and the proportion of time spent in each open state. The effect of SNP (50 nM) on single Ca2+ channel openings was reproduced by 8-Br-cGMP (100 microM), which also reduced channel availability without altering channel properties. The protein kinase inhibitor H-8 (1.5 microM), which exhibits relative specificity for cGMP-dependent protein kinase, completely inhibited the decrease in single-channel availability expected with SNP. The dose-dependent decrease in Ca2+ channel availability caused by SNP was not altered by prior application of 8-Br-cAMP or forskolin, both of which cause an increase in Ca2+ channel availability in these cells. Our findings suggest that NO decreases openings of Ca2+ channels in basilar artery smooth muscle cells without altering channel properties, and that it does so by a mechanism likely to involve cGMP-dependent protein kinase.

Animals↗

PubMed2006

The reproductive phenology of an Amazonian ant species reflects the seasonal availability of its nest sites.

In saturated tropical ant assemblages, reproductive success depends on queens locating and competing for scarce nest sites. Little is known about how this process shapes the life histories of tropical ants. Here I investigate the relationship between nest site availability and an important life history trait, reproductive phenology, in the common Amazonian ant species Allomerus octoarticulatus. A. octoarticulatus is a plant-ant that nests in the hollow, swollen stem domatia on Cordia nodosa. I provide evidence that nest sites are limiting for A. octoarticulatus. Most queens produced by A. octoarticulatus colonies died before locating suitable host plants, and most queens that located hosts died before founding colonies, probably from intraspecific competition among queens for control of host plants. I further show that the reproductive phenology of A. octoarticulatus closely matches the seasonal availability of its nest sites, domatia-bearing C. nodosa saplings. Both the production and flight of A. octoarticulatus reproductives, and the number of C. nodosa saplings available for colonization by ants, peaked from March to May. There was correlative evidence that A. octoarticulatus colonies use temperature as a cue to synchronize their reproduction to the availability of C. nodosa saplings: both the production of reproductives by ant colonies and the number of C. nodosa saplings available for colonization were correlated with temperature, and not with rainfall. All of these results suggest that nest site limitation constrains the reproductive phenology of A. octoarticulatus.

Adaptation, Physiological↗

PubMed1995

The relationship of the retail availability of alcohol and alcohol sales to alcohol-related traffic crashes.

The research literature on the relationship of alcohol consumption to motor vehicle crash risk clearly implicates the importance of minimizing the use of alcohol in conjunction with the operation of motor vehicles. However, there has been relatively little documentation of the direct impact of changes in beverage-specific alcohol sales on the most common surrogate for alcohol-involved traffic crashes, single-vehicle nighttime fatalities. Similarly, there have been few studies of the relationship between the physical availability of alcohol and fatal crash rates which have concurrently controlled for differences in alcohol sales. Indeed, the possibility that reduced availability might lead to increases rather than decreases in fatal crashes (due to increased driving after drinking) has not been adequately tested. This paper presents a series of analyses of time-series cross-sectional data from 38 states over 12 years to evaluate the impact of changes in alcohol sales and the physical availability of alcohol upon single-vehicle nighttime fatal crashes. The results of the study showed, first, that independent of a number of economic and demographic covariates, rates of single-vehicle nighttime fatal crashes were most strongly related to sales of beer and less so to sales of spirits and wine. Second, net of beverage-specific alcohol sales, the physical availability of alcohol was not related to measurable changes in fatal crash rates. Thus, reductions in availability intended to reduce alcohol sales and problems would not appear to increase traffic-related crashes through increased driving exposure.

Accidents, Traffic↗

PubMed1983

Effects of limited-target availability on schedule-induced attack.

Pigeons exposed to a 180-sec fixed-time food schedule could attack a rear-projected conspecific target that was available either (a) continuously throughout the interfood interval, (b) randomly during one 30-sec portion of each interfood interval, or (c) during the final 90 sec of each interval. During continuous-target availability, attack was maximal shortly after food ingestion and progressively decreased thereafter. During random-target availability, five of seven pigeons attacked less per target-access period the later that period occurred within the interfood interval, whereas two subjects exhibited relatively high local attack rates even when access periods occurred within the final third of the interval. When the target was available only during the second half of the interfood interval, attack occurred as soon as the target was presented and progressively decreased throughout the remainder of the target-access period. In general, these results show that schedule-induced attack can be increased by limiting the availability of that target and also indicate that such attack can reliably occur at times other than shortly after food delivery.

Aggression↗

PubMed1991

Pornography and rape: theory and practice? Evidence from crime data in four countries where pornography is easily available.

We have looked at the empirical evidence of the well-known feminist dictum: "pornography is the theory--rape is the practice" (Morgan, 1980). While earlier research, notably that generated by the U.S. Commission on Obscenity and Pornography (1970) had found no evidence of a causal link between pornography and rape, a new generation of behavioral scientists have, for more than a decade, made considerable effort to prove such a connection, especially as far as "aggressive pornography" is concerned. The first part of the article examines and discusses the findings of this new research. A number of laboratory experiments have been conducted, much akin to the types of experiments developed by researchers of the effects of nonsexual media violence. As in the latter, a certain degree of increased "aggressiveness" has been found under certain circumstances, but to extrapolate from such laboratory effects to the commission of rape in real life is dubious. Studies of rapists' and nonrapists' immediate sexual reactions to presentations of pornography showed generally greater arousal to non-violent scenes, and no difference can be found in this regard between convicted rapists, nonsexual criminals and noncriminal males. In the second part of the paper an attempt was made to study the necessary precondition for a substantial causal relationship between the availability of pornography, including aggressive pornography, and rape--namely, that obviously increased availability of such material was followed by an increase in cases of reported rape. The development of rape and attempted rape during the period 1964-1984 was studied in four countries: the U.S.A., Denmark, Sweden and West Germany. In all four countries there is clear and undisputed evidence that during this period the availability of various forms of pictorial pornography including violent/dominant varieties (in the form of picture magazines, and films/videos used at home or shown in arcades or cinemas) has developed from extreme scarcity to relative abundance. If (violent) pornography causes rape, this exceptional development in the availability of (violent) pornography should definitely somehow influence the rape statistics. Since, however, the rape figures could not simply be expected to remain steady during the period in question (when it is well known that most other crimes increased considerably), the development of rape rates was compared with that of non-sexual violent offences and nonviolent sexual offences (in so far as available statistics permitted). The results showed that in none of the countries did rape increase more than nonsexual violent crimes. This finding in itself would seem sufficient to discard the hypothesis that pornography causes rape.(ABSTRACT TRUNCATED AT 400 WORDS)

Cross-Cultural Comparison↗