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PubMed1987

A survey of mental disability among state prison inmates.

To obtain a comprehensive picture of the levels of mental disability in the general state prison population in New York State, the authors gathered data on a random sample of inmates using a survey instrument adapted from the state's level-of-care surveys of the psychiatric population. The sample consisted of 3,332 inmates in the general prison population (9.4 percent) and 352 inmates in prison mental health units. The survey results showed that 8 percent of the state's prison inmates have severe psychiatric or functional disabilities that clearly warrant some type of mental health intervention, and another 16 percent have significant mental disabilities that require periodic services. The specific nature and extent of these disabilities need to be assessed before appropriate services can be developed.

Humans↗
PubMed2006

Effect of essential oil active compounds on rumen microbial fermentation and nutrient flow in in vitro systems.

Two experiments were conducted to determine the effects of several essential oil active compounds on rumen microbial fermentation. In the first experiment, 4 doses (5, 50, 500, and 5,000 mg/L) of 5 essential oil compounds were evaluated using in vitro 24-h batch culture of rumen fluid with a 60:40 forage:concentrate diet (18% crude protein; 30% neutral detergent fiber). Treatments were control (CON), eugenol (EUG), guaiacol, limonene, thymol (THY), and vanillin. After 24 h, the pH was determined, and samples were collected to analyze ammonia N and volatile fatty acids (VFA). The highest dose of all compounds decreased total VFA concentration and increased the final pH. Eugenol at 5 mg/L tended to reduce the proportion of acetate and the acetate to propionate ratio, at 50 and 500 mg/L tended to reduce ammonia N concentration, and at 500 mg/L reduced the proportion of propionate and branched-chain VFA concentration, without affecting total VFA concentration. All other treatments had minor effects or changes occurred only after total VFA concentration decreased. In the second experiment, 8 dual-flow continuous culture fermenters (1,320 mL) were used in 3 replicated periods (6 d of adaptation and 3 d of sampling) to study the effects of THY and EUG on rumen microbial fermentation. Fermenters were fed 95 g/d of DM of a 60:40 forage:concentrate diet (18% crude protein; 30% neutral detergent fiber). Treatments were CON, 10 mg/L of monensin (positive control), and 5, 50, or 500 mg/L of THY and EUG, and were randomly assigned to fermenters within periods. During the last 3 d of each period, samples were taken at 0, 2, 4, and 6 h after the morning feeding and analyzed for peptides, amino acids, and ammonia N concentrations, and total and individual VFA concentrations. Monensin changed the VFA profile as expected, but inhibited nutrient digestion. Eugenol and THY decreased total VFA concentration and changed the VFA profile, and only 5 mg/L of THY tended to reduce the proportion of acetate, increased the proportion of butyrate, and increased the large peptides N concentration without decreasing total VFA concentration. Most of these essential oil compounds demonstrated their antimicrobial activity by decreasing total VFA concentration at high doses. However, EUG in batch fermentation and 5 mg/L of THY in continuous culture modified the VFA profile without decreasing total VFA concentration, and EUG in batch fermentation decreased ammonia N concentration.

Acetates↗
PubMed2005

Comparison of macroinvertebrate sampling methods for nonwadeable streams.

Bioassessment of nonwadeable streams in the United States is increasing, but methods for these systems are not as well-developed as for wadeable streams. In this study, we compared six macroinvertebrate field sampling methods for nonwadeable streams adapted from those used by three major programs: the U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program-Surface Waters, the U.S. Geological Survey's National Water Quality Assessment Program, and the Ohio Environmental Protection Agency, Division of Surface Water Biocriteria Program. We performed all six methods at 60 sites across four rivers and measured water chemistry and physical habitat at each site to assess abiotic conditon. Sites were divided into two groups: those influenced by navigational lock and dam structures (restricted flow, or RF) and those free-flowing or with lowhead dams (run-of-the-river, or ROR). Metrics based on passive Hester-Dendy artificial substrate samplers differed greatly from active sampling methods (i.e., using nets) but represented abiotic conditions well in both ROR and RF sites. Although metric values were similar across certain sampling methods, the metrics significantly correlated with abiotic variables varied among methods and between ROR and RF sites. These results emphasize that methods are not interchangeable, and the ability to detect certain stressors depends on sampling method.

Animals↗
PubMed2000

A method for global analysis of complex proteomes using sample prefractionation by solution isoelectrofocusing prior to two-dimensional electrophoresis.

Two-dimensional electrophoresis is a critical technique for proteome research, but currently available methods are not capable of resolving the >10,000 protein components in most eukaryotic proteomes. We have developed and demonstrated the utility of a novel solution isoelectrofocusing device and method that can reproducibly prefractionate cell extracts into well-defined pools prior to 2D PAGE on a scale directly compatible with the high sensitivity of proteome studies. A prototype device was used to separate metabolically radiolabeled Escherichia coli extracts in method optimization and proof-of-principle experiments. Samples were loaded into separation chambers divided by thin polyacrylamide gels containing immobilines at specific pH values and isoelectrically focused for several hours, which resulted in well-resolved fractions. Total recoveries in the fractionated samples were greater than 80% and most protein spots in the original sample were recovered after this prefractionation step. Nonideal behavior (precipitation/aggregation), typically encountered when unfractionated samples at high protein loads were applied directly to either narrow- or broad-range IPG gels, was dramatically reduced. Hence this approach allows increases in overall protein loads, resolution, and dynamic detection range compared with either alternative prefractionation methods or direct use of parallel narrow pH range gels without sample prefractionation. The pH ranges and number of fractions can be readily adapted to the requirements of specific types of samples and projects. This method should allow quantitative comparisons of at least 10,000 protein components on a series of narrow pH range gels, and protein detection limits are estimated to be 1000 molecules per cell when mammalian proteomes are fractionated into five or more pools.

Cell Extracts↗
PubMed1998

Development of a rapid and sensitive quantitative assay for rotavirus based on flow cytometry.

A very sensitive and accurate flow cytometry (FC) based method have developed to quantitate rotavirus infection in MA104 cells. Confluent cell monolayers were infected with serial dilutions of rotavirus SA11. After infection, the cells were recovered with the aid of trypsin and then reacted with monoclonal antibody M60 (specific for the rotavirus outer capsid protein, VP7), followed by a second antibody (anti-mouse IgG-FITC). A FACScan FC was used to estimate the number of infected cells, as well as the level of infection. Viral infection was optimised by varying the concentration of trypsin used in the maintenance medium. The FC method enables many cells to be screened quickly for infectivity, and can detect low levels of virus. This method can be adapted to monitor the presence of other viruses in clinical and environmental samples without the need for prolonged periods of adaptation to growth in tissue culture.

Animals↗
PubMed1999

The gas transporting systems: limits and modifications with age and training.

The interplay of cardiovascular and cellular oxygen uptake determinants of aerobic performance and the system adaptations to training in different population samples are examined in order to describe the limitation. With VO2max, a central limitation following myocardial infarction and ageing is modified with training. Peripheral adaptations occur and stroke volume may be increased primarily through improved diastolic filling. In submaximal perturbations, control of the increase in O2 uptake at exercise onset (O2 kinetics) is most often under peripheral metabolic control, but in exceptions may also be limited by central factors. In young and old the peripheral machinery is matched to the growth (puberty) and loss (ageing) of muscle mass. Cardiac stroke volume capacity may adjust following the changes in muscle mass. Submaximal endurance is closely influenced by the anaerobic threshold (theta(an)) and peripheral factors of oxidative metabolism. Relative to VO2max, the theta(an) is low in children and high in older adults, perhaps reflecting a slow time course in full development and loss of peripheral adaptations. Remarkable increases in endurance performance are related to relatively small changes in the maximal capacity and the relative intensity of performance.

Adaptation, Physiological↗
PubMed1996

Does acculturation influence psychosocial adaptation and well-being in Native Hawaiians?

Native Hawaiians have suffered higher disease rates and achieved lower educational and economic levels than other ethnic groups living in Hawaii. This study tests the hypothesis that cultural affiliation protects against psychosocial pathology in Hawaiians. Subjects included 172 Hawaiians of varying blood quantum and 92 non-Hawaiians. The Na Mea Hawai'i, a rationally derived, empirically validated measure of Hawaiian acculturation was administered to all subjects in addition to psychological tests which included 19 visual analogue scales that measure both state and trait variables. The Na Mea Hawai'i proved excellent at differentiating Hawaiians from non-Hawaiians (p = .0001), and it correlated well with blood quantum (r = 0.31, p = .0001). Low acculturation scores among Hawaiians did not correlate with any measure of discontent or psychosocial pathology irrespective of blood quantum. We conclude that Na Mea Hawai'i is a valid measure of Hawaiian acculturation, and that adaptation of the Hawaiians in our sample has been unaffected by level of acculturation.

Acculturation↗
PubMed1990

Wavelength-independent microradiography used for quantification of mineral changes in thin enamel and dentin samples with natural surfaces, pseudo-thick tooth sections, and whole teeth.

Tests of the efficacy of therapeutic agents for caries repair or prevention in vitro or in situ should be performed as realistically as possible. This implies the non-destructive assessment of mineral changes in whole teeth. In this study, Wavelength-independent Microradiography (WIM), a non-destructive form of microradiography that uses polychromatic x-rays, was tested for its use in following mineral changes during demineralization of whole teeth. Since the method was, in a previous paper, only tested on flat samples of about 0.3 mm in thickness, the present study aimed to adapt and test WIM for use on thicker samples. This was done in three steps: In the first step, natural surfaces were introduced. The mineral content of enamel and dentin samples about 0.3 mm in thickness and with natural (curved) surfaces was determined by WIM, and the result was compared with mineral measurements performed with Longitudinal Microradiography (LMR). A correlation of 0.98 was found for both the enamel and the dentin samples. In the second step, the thickness of whole teeth was added. Thick tooth sections were simulated by addition of a 5-mm block of dentin to such thin enamel and dentin samples. Mineral measurements with WIM of the samples plus the dentin block were compared with mineral measurements of the thin samples (without block). A correlation of 0.97 was found for enamel, and one of 0.90 was found for dentin. Finally, in a third step, the demineralization of whole premolars was followed as a function of time.

Dental Caries↗
PubMedDate not supplied

Assessment of the androgen environment within the human testis: minimally invasive method to obtain intratesticular fluid.

Previous studies of the rat have shown that testosterone concentrations within the interstitial and seminiferous tubularfluids of the testes are significantly higher than normal serum levels, and further, that although intratesticular testosterone concentration can be substantially reduced without an effect on spermatogenesis, the concentration that is minimally required to maintain spermatogenesis is also substantially higher than serum levels. The purpose of the present study was to adapt a minimally invasive technique to sample human intratesticular fluid to enable parallel observations in man. To this end, aspiration methods were first developed for the rat testis and then adapted to the human. The testosterone concentration in fluid obtained by unilateral aspiration of rat testes was approximately 50 ng/mL, similar to the known concentration in seminiferous tubular fluid. These aspiration methods were then adapted to obtain intratesticular fluid from human testes. Studies of 12 fertile human subjects demonstrated that percutaneous testicular aspiration could be performed safely and successfully using a 19-gauge needle. Nine additional human subjects had bilateral testicular aspiration and simultaneous measurement of peripheral blood testosterone levels. Testicular aspirations yielded 8 to 117 microL of fluid from each testicle. The mean concentration of testosterone in aspirates obtained from the 21 patients was 609 +/- 50 ng/mL. Dihydrotestosterone and 3alpha-androstanediol concentrations were quite low, below the limits of detection of our assay. The SHBG/ABP concentration in the aspirates was 8.5 +/- 1.1 nM. These results define testosterone as the major androgenic steroid in the human testis, as in the rat testis, and indicate that the testosterone concentration within the human testis is approximately 200-fold greater than that of SHBG/ABP, and more than 100-fold greater than the concentration of testosterone found in normal human serum.

Adult↗
PubMed1991

Monitoring of upper oesophageal sphincter pressure in children.

In children technical limitations of upper oesophageal sphincter manometry have restricted investigation to the pull through technique under sedation. In this study we have used an adapted sleeve manometric technique for upper oesophageal sphincter monitoring in unsedated children and determined the influence of the state of arousal on upper oesophageal sphincter pressure. Twenty six children aged 3 to 42 months (median 17.5 months), who were referred for evaluation of oesophageal motor function, were studied with dual sleeve manometric assemblies which monitored upper and lower oesophageal sphincter pressures simultaneously. Pharyngeal, oesophageal body, and gastric pressures were also monitored with seven perfused side holes. Recordings were made for four hours after a meal and were technically successful in 24 children. The child's state of arousal was scored every 12th minute as follows: (A) resting, eyes closed, (B) resting, eyes open, (C) moving but comfortable, (D) restless and uncomfortable, (E) crying. In 67% of the 12 minute samples the children showed good adaptation to the procedure (arousal states A to C). There was a highly significant difference in upper oesophageal sphincter pressure between each of the arousal states (p less than 0.0001), being lowest in category A at (mean (SD) 18.1 (10.3) mmHg and highest in category D 55.7 (13.2) mm Hg. Abrupt changes in the state of arousal were associated with equally abrupt changes in upper oesophageal sphincter pressure. The state of arousal of unsedated children has an important influence on upper oesophageal sphincter pressure. It is essential that this factor is controlled for in any studies of upper oesophageal sphincter tone in children. The sleeve technique is capable of monitoring upper oesophageal sphincter motility for prolonged periods in unsedated children.

Arousal↗
PubMed2000

Voltammetry on microfluidic chip platforms

Microfluidic chip devices are shown to be attractive platforms for performing microscale voltammetric analysis and for integrating voltammetric procedures with on-chip chemical reactions and fluid manipulations. Linear-sweep, square-wave, and adsorptive-stripping voltammograms are recorded while electrokinetically "pumping" the sample through the microchannels. The adaptation of voltammetric techniques to microfluidic chip operation requires an assessment of the effect of relevant experimental variables, particularly the high voltage used for driving the electroosmotic flow, upon the background current, potential window, and size or potential of the voltammetric signal. The exact potential window of the chip detector is dependent upon the driving voltage. Manipulation of the electroosmotic flow opens the door to hydrodynamic modulation (stopped-flow) and reversed-flow operations. The modulated analyte velocity permits compensation of the microchip voltammetric background. Reversal of the driving voltage polarity offers extended residence times in the detector compartment. Rapid square-wave voltammetry/flow injection operation allows a detection limit of 2 x 10(-12) mol (i.e., 2 pmol) of 2,4,6-trinitrotoluene (TNT) in connection with 47 nL of injected sample. The ability of integrating chemical reactions with voltammetric detection is demonstrated for adsorptive stripping measurements of trace nickel using the nickel-dimethylglyoxime model system. The voltammetric response is characterized using catechol, hydrazine, TNT, and nickel as test species. The ability to perform on-chip voltammertic protocols in advantageous over nanovial voltammetric operations that lack a liquid-handling capability. Coupling the versatility of microfluidic chips with the rich information content of voltammetry thus opens an array of future opportunities.

Journal Article↗
PubMed2000

Adaptation of the Diabetes Health Profile (DHP-1) for use with patients with Type 2 diabetes mellitus: psychometric evaluation and cross-cultural comparison.

AIMS: To adapt the Diabetes Health Profile (DHP-1) for use with English speaking patients with Type 2 diabetes mellitus and to evaluate the psychometric properties of the adapted measure in a UK and Danish sample of insulin, tablet and diet-treated patients with Type 2 diabetes. METHODS: Following linguistic adaptation using the forward-backward translation procedure, the 32-item DHP-1 was sent to 650 and 800 consecutively selected UK and Danish patients with Type 2 diabetes. Construct validity was assessed using principal axis factoring. Factor stability was assessed across language groups using the coefficient of congruence. Reliability was evaluated using Cronbach's alpha and multi-trait analysis, including item convergent/discriminant validity. Subscale discriminant validity was assessed through known groups with one-way ANOVA and post hoc Scheffe tests for multiple comparisons. RESULTS: Eighteen items (56.25%) were retained following initial item analysis. A three-factor solution accounting for 45.6% and 40.3% of the total explained variance was identified in the UK and Danish samples, respectively. Factors were interpreted as psychological distress (PD), barriers to activity (BA) and disinhibited eating (DE). Factor congruence between language groups ranged from 0.98 to 0.99 and Cronbach's alpha ranged between 0.70 and 0.88. Item scaling success for both language versions was 88.9%. BA scores discriminated between treatment groups in both language groups (F = 24.24, P < 0.001; F = 7.68, P < 0.001) and PD scores in the UK sample (F = 20.97, P < 0.001). CONCLUSIONS: The DHP-18 developed for use with patients with Type 2 diabetes has been shown to have satisfactory internal reliability and validity and measurement equivalence across language groups.

Affect↗
PubMed1987

Appraisals of control and predictability in adapting to a chronic disease.

In a sample of 92 patients with rheumatoid arthritis, we examined interrelations among various control appraisals, illness predictability, psychosocial adjustment, mood, and illness status. Perceiving greater personal control over the disease and symptoms and perceiving greater health-care-provider control over symptoms were associated with greater illness predictability. Patients reported more personal control over their symptoms than over the course of the disease and thought that their health care providers had more control over disease course than they did themselves. Multiple regression analyses showed that perceiving greater personal control over one's medical care and treatment was associated with positive mood and psychosocial adjustment. Negative mood was also associated with the belief that providers have greater control over the patient's daily symptoms. Patients who had a more severe disease and expressed greater personal control over its course reported greater mood disturbance and were rated as exhibiting less positive adjustment, but those who had more severe daily symptoms and expressed greater personal control over their symptoms reported less mood disturbance. These findings are discussed in terms of the possible benefits of patients' active participation in their care and the implications of perceiving personal and others' control over more or less controllable aspects of the illness, especially when the illness is more severe.

Activities of Daily Living↗
PubMedDate not supplied

Distressed and stress resistant nurses.

This study examines the relative contribution of personality, coping, and family support to adaptation to stress in nursing. The sample (N = 1,043, mean age = 33.8 years) were nurses from three large public hospitals in Singapore. The findings indicated that stress resistant nurses who adapted to high work stress with good mental health status as measured by the General Health Questionnaire (GHQ-12) developed by Goldberg (1972) had a higher self-esteem and were more internal in locus of control than the distressed nurses who reported poor mental health status under high work stress. The use of negative emotion focused coping was less frequent among the stress-resistant nurses who also had greater supports from family relationships. Discriminant function analysis revealed that behavioral coping (e.g., enhancement of ability and physical health) had greater contribution to stress resistance than cognitive coping (e.g., acceptance of situations or change of perspectives). The findings were discussed with reference to the high level of performance demanded by nursing.

Adaptation, Psychological↗
PubMed2003

The signaling adapters fibroblast growth factor receptor substrate 2 and 3 are activated by the thyroid TRK oncoproteins.

The thyroid TRK oncogenes are generated by chromosomal rearrangements juxtaposing the neurotrophic tyrosine receptor kinase type 1 (NTRK1) tyrosine kinase domain to foreign activating sequences. TRK oncoproteins display a constitutive tyrosine kinase activity resulting in the capability to transform NIH3T3 cells. The TRK oncoproteins' signal transduction has been in part elucidated, and it involves several signal transducers activated by the NGF-stimulated NTRK1 receptor. In this paper, we investigate the role of FRS2 and FRS3, two related adapter proteins activated by fibroblast growth factor and NTRK1 receptors, in the signaling of the thyroid TRK-T1 and TRK-T3 oncogenes. By a combination of in vitro and in vivo assays, we demonstrate that both fibroblast growth factor receptor substrate (FRS)2 and FRS3 are recruited and activated by TRK-T1 and TRK-T3. Interaction studies using different TRK-T3 mutants indicate that FRS3 is recruited by the same tyrosine residue interacting with Shc and FRS2. Expression studies show different expression patterns of the FRS adapters in normal and tumor thyroid samples: FRS3 is expressed in both normal and thyroid tumor samples, whereas FRS2 is not expressed in normal thyroid but is differentially expressed in some tumors. Altogether, our data indicate that the FRS2 and FRS3 adapters may have a role in thyroid carcinogenesis triggered by TRK oncogenes.

3T3 Cells↗
PubMedDate not supplied

Enhanced surveillance of foodborne mycotoxins by immunochemical assay.

Mycotoxins are a chemically diverse group of fungal secondary metabolites with a wide range of toxic effects. Conventional thin-layer and instrumental methods of mycotoxin analysis are time-consuming and make routine safety and quality control screening of these compounds in agricultural commodities difficult. As an alternative, specific polyclonal and monoclonal antibodies have been raised against mycotoxin-protein conjugates and used in sensitive radioimmunoassays (RIAs) and enzyme-linked immunosorbent assays (ELISAs). One of the simplest ELISA approaches involves competition for a solid-phase antibody between a mycotoxin-enzyme conjugate and an unconjugated mycotoxin in the sample extract. ELISAs have been developed for aflatoxins B1 and M1, zearalenone, T-2 toxin, and deoxynivalenol, which are highly specific, rapid (10 min), easily adaptable for analyzing large numbers of samples, and directly applicable to assaying methanol-water extracts of a wide range of foods. Several commercial mycotoxin ELISAs using this approach (most typically for aflatoxin B1) are currently being marketed. Since ELISAs will be used in large part by personnel with limited technical expertise, individual kits must be critically evaluated by analytical chemists for suggested sampling procedures, efficiency of extraction, cross-reactivity, mycotoxin recovery, assay reproducibility, and product shelf-life prior to routine use in food safety and quality control screening.

Food Contamination↗
PubMed1997

Effect of support groups with coaching on adaptation to early stage breast cancer.

The effects of 8-week cancer support groups (CSGs) with and without coaching on adaptation were tested in a sample of 181 women with newly diagnosed early stage breast cancer. CSG participation with coaching resulted in higher quality of relationship with significant other at CSG conclusion; this effect was not sustained 8 weeks later. CSG participation had no effect on symptom distress, emotional distress, or functional status. On average, symptom distress was low, emotional distress was moderate, and functional status was relatively high. Independent of CSGs, symptom distress decreased and functional status increased over time from entry into the study to 16 weeks later. Further research is needed to determine the optimal starting time and length for CSGs.

Adaptation, Psychological↗