Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Mass Behavior”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 649 records · Page 36Linked to original sources
PubMed1997

Behavior-dependent activities of a central pattern generator in freely behaving Lymnaea stagnalis.

Cyclic or repeated movements are thought to be driven by networks of neurons (central pattern generators) that are dynamic in their connectivity. During two unrelated behaviors (feeding and egg laying), we investigated the behavioral output of the buccal pattern generator as well as the electrical activity of a pair of identified interneurons that have been shown to be involved in setting the level of activity of this pattern generator (PG). Analysis of the quantile plots of the parameters that describe the behavior (movements of the buccal mass) reveals that during egg laying, the behavioral output of the PG is different compared with that during feeding. Comparison of the average durations of the different parts of the buccal movements showed that during egg laying, the duration of one specific part of buccal movement is increased. Correlated with these changes in the behavioral output of the PG were changes in the firing rate of the cerebral giant neurons (CGC), a pair of interneurons that have been shown to modulate the activity of the PG by means of multiple synaptic contacts with neurons in the buccal ganglion. Interval- and autocorrelation histograms of the behavioral output and CGC spiking show that both the PG output and the spiking properties of the CGCs are different when comparing egg-laying animals with feeding animals. Analysis of the timing relations between the CGCs and the behavioral output of the PG showed that both during feeding and egg laying, the electrical activity of the CGCs is largely in phase with the PG output, although small changes occur. We discuss how these results lead to specific predictions about the kinds of changes that are likely to occur when the animal switches the PG from feeding to egg laying and how the hormones that cause egg laying are likely to be involved.

Action Potentials↗
PubMed2006

Risk factors for recurrent lower extremity cellulitis in a U.S. Veterans Medical Center population.

BACKGROUND: Despite the frequency of recurrent acute cellulitis of the lower extremities, factors associated with this infection have not been previously assessed in a case-control study among patients admitted to U.S. hospitals. METHODS: We compared the clinical characteristics of 47 patients with those of 94 age- and sex-matched control subjects admitted to the Miami Veterans Affairs Medical Center. RESULTS: In a multivariate analysis, two physical factors, lower extremity edema and body mass index, one behavioral factor, smoking, and one demographic factor, homelessness, were significantly and independently associated with recurrent cellulitis. The latter two factors have not previously been reported to be independently associated with cellulitis. CONCLUSIONS: Our results suggest that increased emphasis on weight loss, smoking cessation, and improved foot hygiene in the homeless might decrease recurrences of lower extremity cellulitis.

Body Mass Index↗
PubMed1992

Habitual physical activity in adult IDDM patients. A study with portable motion meters.

The objective of this study was to assess the habitual physical activity of insulin-dependent diabetes mellitus (IDDM) patients on intensive insulin therapy. This case-control study consisted of 34 IDDM patients (14 on multiple injection therapy, 20 on continuous subcutaneous insulin infusion [CSII], and control subjects matched for sex, age, weight, height, body mass index, smoking behavior, and occupational status). Seven IDDM patients were studied before and after changing from multiple injection to CSII therapy. All patients were well controlled according to HbA1c. Portable motion meters were used to assess habitual physical activity during 7 consecutive days with appreciable reproducibility (coefficient of variation 1.24%) and agreement to standardized activity protocols (r = 0.96, P < 0.001). Habitual physical activity was similar in IDDM patients on injection treatment and in controls, respectively. CSII-treated patients exhibited on the average 17% less habitual physical activity than control subjects (P < 0.05). Changing from multiple injection therapy to CSII lowered habitual physical activity insignificantly in seven patients. There was no indication of decreasing physical exercise (e.g., sports) by CSII in this patient group. No correlations were found between habitual physical activity and HbA1c or body mass index, respectively. Habitual physical activity is similar in IDDM patients on multiple injection therapy and control subjects, but may decrease by CSII therapy.

Adult↗
PubMed1993

Maintaining mobility in late life. II. Smoking, alcohol consumption, physical activity, and body mass index.

While positive health behaviors have been shown to extend life, their association with extending active life has not been well investigated. In this report, several health behaviors were investigated in relation to maintaining mobility during 4 years of follow-up among 6,981 men and women aged 65 years and older with intact mobility at baseline between 1981 and 1983 who lived in one of three communities: East Boston, Massachusetts; Iowa and Washington counties, Iowa; and New Haven, Connecticut. Intact mobility, defined as the ability to climb up and down stairs and walk a half mile, was determined annually by interview, and study subjects were classified into one of three categories at the end of 4 years of follow-up: 1) maintained mobility (55.1%); 2) lost mobility (36.2%); or 3) died without evidence of having lost mobility prior to death (8.7%). After adjustment for age and all of the health behaviors, risk of losing mobility was significantly associated with current smoking, not consuming alcohol compared with small-to-moderate amounts of alcohol consumption, high (> 80th percentile) compared with moderate (21-80th percentiles) body mass index, and low physical activity levels in both men and women. These findings suggest that positive health behaviors can not only extend longevity but also reduce the risk of losing mobility and independence in later life.

Activities of Daily Living↗
PubMed1999

Savignin, a potent thrombin inhibitor isolated from the salivary glands of the tick Ornithodoros savignyi (Acari: Argasidae).

A thrombin (E.C. 3.4.21.5) inhibitor, savignin, was isolated from the salivary glands of Ornithodoros savignyi by a combination of size exclusion, anion-exchange, and reversed-phase chromatography. The inhibitor has a molecular mass of 12,430.4 Da as determined by electrospray mass spectrometry. The behavior of savignin during anion-exchange chromatography indicated that it has an acidic pI. The available N-terminal sequence (residues 1-11) differed from that of ornithodorin with only one residue. Savignin inhibits thrombin-induced platelet aggregation, but has no effect on ADP- or collagen-induced aggregation. Kinetic studies indicated that savignin is a competitive, slow-, tight-binding inhibitor of alpha-thrombin (K(i) = 4.89 +/- 1.39 pM). Tight-binding kinetics showed that the inhibitor has a lower affinity for gamma-thrombin (K(i) = 22.3 +/- 5.9 nM). Plasmin, factor Xa, and trypsin are not inhibited by savignin.

Amino Acids↗
PubMed2002

Size-based separation of synthetic polyelectrolytes in entangled polymer solution capillary electrophoresis: the effect of binary mixtures of separating polymers differing in molecular mass.

The influence on the electrophoretic behavior of polystyrenesulfonates of the percentage of high-molecular-mass chains in an entangled poly(ethylene oxide) solution having a bimodal molecular mass distribution has been investigated and compared with the results obtained for similar solutions of unimodal molecular mass distribution. The comparisons between the different separating polymer solutions were made at a constant total mass concentration, so as to keep constant the mesh size and to highlight the sole effect of the network dynamics. The use of binary polymer mixtures of two different molecular masses but of same nature can be a convenient alternative to modulate the dynamics of the network and the viscosity of the separating medium. A 20-30% content of high-molecular-mass chains in an entangled poly(ethylene oxide) solution having a binary molecular mass distribution appears to be a good compromise for a moderate viscosity and a good separation selectivity in comparison with a solution containing only chains of high molecular mass at the same concentration.

Electrophoresis, Capillary↗
PubMed1998

Effect of the sample matrix on the determination of indinavir in human urine by HPLC with turbo ion spray tandem mass spectrometric detection.

The HPLC/tandem mass spectrometric (LC/MS/MS) behavior of indinavir, an HIV protease inhibitor, in human urine is presented as an example of a case where endogenous matrix components were found to interfere with the ionization of the target analyte. The MS/MS system used for these experiments was equipped with a turbo ion spray LC interface. Results from two sample preparation procedures (direct dilution of urine vs urine extraction) and two chromatographic systems (low vs. high capacity factor (k')) for the analytes were compared. Additionally, the precision of the analysis that was achieved while using a stable isotope labeled internal standard is contrasted with the results obtained using an analog of indinavir as internal standard. The results obtained indicated that during development and validation of LC/MS/MS based assays the potential effect of co-eluting 'unseen' endogenous species should be evaluated to ensure that sample preparation and chromatography is adequate to overcome the matrix effect problems.

Body Fluids↗
PubMed2006

Comparison of analytical strategies for the chromatographic and mass spectrometric measurement of brominated flame retardants: 1. Polybrominated diphenylethers.

The chromatographic and mass spectrometric (MS) behaviors of 49 polybrominated diphenylether (PBDE) homologues toward various techniques is investigated. Special attention is paid to chromatographic separation, ionization processes, and signal acquisition modes. Different liquid chromatographic (LC) separation systems and gas chromatographic (GC) temperature program parameters are studied. For LC-MS experiments, the ionization efficiencies of electrospray, atmospheric pressure chemical ionization, and atmospheric pressure photoionization (APPI) are evaluated. For GC-MS experiments, negative chemical ionization with ammonia as reagent gas as well as negative and positive electron impact (EI) ionization are studied. Thus, fragmentation pathways of PBDEs are investigated, with the main objective being to determine the sensitivity/specificity balance of each tested technique with respect to their potential respective application (parent compound focusing, metabolite identification, and screening of analogue compounds). Finally, performances of the different tested techniques are compared and evaluated in terms of detection limits on standard solutions for each homologue group. In terms of ionization, EI remains the best compromise between sensitivity and specificity with possible complementary applications in MS-MS and high-resolution MS. Nevertheless, APPI appears to be a promising alternative.

Chromatography, Liquid↗
PubMedDate not supplied

Body weight and health care among women in the general population.

OBJECTIVE: To examine the relation between body mass index ([BMI] calculated as weight in kilograms divided by the square of height in meters) and the use of medical care services among a nationally representative sample of women. DESIGN AND SETTING: Multistage cluster-area probability sampling survey. Data are from the Cancer Control and Health Insurance supplements of the 1992 National Health Interview Survey conducted by the National Center for Health Statistics. Respondents were 6981 women aged 18 years or older residing in the United States who self-reported sociodemographic information and the use of health care services. MAIN OUTCOME MEASURES: Interval (< or = 3 years vs > 3 years) since most recent mammography, clinical breast examination, gynecologic examination, and Papanicolaou smear and the number of physician visits in the year before the survey. RESULTS: When age, race, income, education, smoking, and health insurance status were adjusted for, the BMI was directly related to delaying clinical breast examinations, gynecologic examinations, and Papanicolaou smears. Obese women (BMI of 35) were more likely than nonobese women (BMI of 25) to delay clinical breast examinations (odds ratio, 1.26; 95% confidence interval, 1.00-1.58), gynecologic examinations (odds ratio, 1.39; 95% confidence interval, 1.15-1.69), and Papanicolaou smears (odds ratio, 1.29; 95% confidence interval, 1.04-1.58). The BMI was not significantly related to delays in mammography. It was also related to increased physician visits (P = .001). CONCLUSION: Among women, an increased BMI is associated with decreased preventive health care services, which may exacerbate or even account for some of the increased health risks of obesity.

Adult↗
PubMed1998

Well-being and morbid obesity in women: a controlled therapy evaluation.

OBJECTIVE: Morbidly obese individuals are unlikely to reach and maintain normative weights. Thus, interventions aimed at alleviating corollary problems, independent of attempts at weight loss, are appropriate. A cognitive group treatment program (CT) was developed which incorporated a nondieting approach, regular exercise, and use of alternative coping skills. Weight loss per se was not a focus of the intervention. The purpose of the current work was to evaluate this program in a controlled, comparative treatment outcome study. METHOD: Sixty-two obese women with a history of treatment failures were randomly assigned to the CT program, a behavior therapy weight loss program (BT), or a wait-list control group. RESULTS: For CT participants, depression, anxiety, and eating-related psychopathology decreased significantly over the course of treatment while perceptions of self-control increased; BT and control subjects showed no significant changes in these variables. Women in both active treatment groups lost significant amounts of weight, while members of the control group showed a nonsignificant increase in weight. At 6-month follow-up, treatment benefits were maintained. DISCUSSION: Findings suggest that interventions not directly aimed at weight loss can enhance psychological well-being and thus may be appropriate for some obese women.

Adaptation, Psychological↗
PubMed2002

Mass allometry of the appendicular skeleton in terrestrial mammals.

Most analyses on allometry of long bones in terrestrial mammals have focused on dimensional allometry, relating external bone measurements either to each other or to body mass. In this article, an analysis of long bone mass to body mass in 64 different species of mammals, spanning three orders of magnitude in body mass, is presented. As previously reported from analyses on total skeletal mass to body mass in terrestrial vertebrates, the masses of most appendicular bones scale with significant positive allometry. These include the pectoral and pelvic girdles, humerus, radius+ulna, and forelimb. Total hindlimb mass and the masses of individual hindlimb bones (femur, tibia, and metatarsus) scale isometrically. Metapodial mass correlates more poorly with body mass than the girdles or any of the long bones. Metapodial mass probably reflects locomotor behavior to a greater extent than do the long bones. Long bone mass in small mammals (<50 kg) scales with significantly greater positive allometry than bone mass in large (>50 kg) mammals, probably because of the proportionally shorter long bones of large mammals as a means of preserving resistance to bending forces at large body sizes. The positive allometric scaling of the skeleton in terrestrial animals has implications for the maximal size attainable, and it is possible that the largest sauropod dinosaurs approached this limit.

Animals↗
PubMedDate not supplied

Tailgut cysts: CT and MR findings.

Two cases of tailgut cysts are reported. These lesions are rare and congenital, lying anterior to the sacrum and posterior to the rectum. CT findings are described. For one patient MR evidence is also presented. In a second case, the mass showed malignant behavior with local recurrence.

Adenocarcinoma↗
PubMedDate not supplied

Citalopram versus fluoxetine for the treatment of patients with bulimia nervosa: a single-blind randomized controlled trial.

The most studied and most frequently used pharmacologic treatments in bulimia nervosa are the selective serotonin reuptake inhibitors (SSRIs), in particular, fluoxetine. Less is known about the efficacy of the other SSRIs. To compare fluoxetine with citalopram in the treatment of bulimic patients, 37 bulimic patients were randomized to receive fluoxetine (n=18) or citalopram (n=19); these patients were assessed with regard to clinical (ie, body mass index, pathologic behaviors), psychopathologic (Eating Disorder Inventory-2, Body Shape Questionnaire, Binge-Eating Scale, Beck Depression Inventory), personality (Temperament and Character Inventory), and clinical global impression measures. These measures were compared between the 2 treatment groups at baseline and at the end of treatment. Dropout rates were similar in the 2 groups. Both groups showed significant improvement in eating psychopathology, angry feelings, and clinical global impression. Patients in the fluoxetine group displayed a greater reduction in introjected anger, whereas those in the citalopram group displayed a greater reduction in depressive feelings. Both treatments showed some effect on outcome measures, but efficacy profiles did not overlap. Citalopram may be useful in depressed patients with bulimia, whereas fluoxetine is more specific for those with introjected anger and bulimia.

Adult↗
PubMed1983

Cholesterol content of red blood cells and low-density lipoproteins in hypertriglyceridemia.

The red blood cells and the low-density lipoproteins in hypertriglyceridemia have a lower ratio of unesterified cholesterol to phospholipid than normal. The low-density lipoproteins are also smaller and more dense in hypertriglyceridemia, and contain only 45% of the normal unesterified cholesterol mass. The phase behavior of the lipids shows that normal red cells and low-density lipoproteins are close to saturation with cholesterol, whereas in hypertriglyceridemia less cholesterol is present. Because newly secreted triacylglycerol-rich lipoproteins are poor in cholesterol, their excess production and transport in hypertriglyceridemia may prevent maintenance of the normal cholesterol content of blood cells and low-density lipoproteins. Partitioning of cholesterol into triacylglycerol-rich lipoproteins is able to account for significant fluxes of unesterified cholesterol in the plasma compartment.

Cholesterol↗
PubMed1993

Effects of a preventive cardiology curriculum on behavioral cardiovascular risk factors and knowledge of medical students.

We evaluated a Preventive Cardiology Academic Award (PCAA) program designed to integrate preventive cardiology concepts into the medical school curriculum. Diet, preventive cardiology knowledge, preventive cardiology attitudes, exercise behavior, and body mass index were compared at entrance to medical school and during the graduation year. Complete data were available on 94 students (65 men and 29 women). Similar data from students who graduated in 1987, prior to the introduction of the PCAA curriculum, served as a control. Women showed a significant enhancement in attitude towards cardiovascular disease (CVD) prevention, while both men and women significantly increased their knowledge about CVD prevention. The frequency of planned physical activity decreased significantly in both sexes and men showed a significant increase in body mass index. Men significantly reduced total calories, percent of calories from fat and saturated fat and dietary cholesterol and increased fiber intake. In women, the only significant reduction was in total calories. In comparison to the control class that did not have the program, men receiving the PCAA curriculum reduced dietary cholesterol, dietary fat, saturated fat and monounsaturated fat. Changes in these dietary parameters were nonsignificant for women in comparison to the control class women. Additional analyses showed no systematic secular trends in dietary or other variables in classes entering from 1986 to 1990. We conclude that the PCAA curriculum changes have favorably affected the preventive cardiology knowledge, attitudes and diet of medical students.

Adult↗
PubMed2002

Comparative study on characteristics of lysozymes from the hemolymph of three lepidopteran larvae, Galleria mellonella, Bombyx mori, Agrius convolvuli.

Lysozymes were purified from the hemolymph of three immunized Lepidopteran larvae, Galleria mellonella, Bombyx mori, Agrius convolvuli to compare their physico-chemical properties and antibacterial activities with those of chicken lysozyme. Four lysozymes including the one from chicken had similar molecular masses and chromatographic behavior on reverse phase-high pressure liquid chromatography. Western blotting analysis using an antibody raised against G. mellonella revealed that lysozyme cross-reacted with two other insect lysozymes but not with commercial chicken lysozyme. Antibacterial activities of lysozymes were measured in two types of tests: radial diffusion assay and colony count assay. Our antibacterial tests revealed that all lysozymes have strong activities against Gram-positive bacteria and three insect lysozymes still retain a little potency against Gram-negative bacteria, while chicken lysozyme has no activity against Gram-negative bacteria. Taken together, we conclude three Lepidopteran lysozymes have a common distinct structure and have an antibacterial activity, which is absent in chicken lysozyme, against Gram-negative bacteria.

Animals↗
PubMed1975

Presence of the methylester of 5-carboxymethyl uridine in the wobble position of the anticodon of tRNAIII Arg from brewer's yeast.

The methylester of 5-carboxymethyluridine (mcm5U), its degradation product 5-carboxymethyluridine (cm5U) and the corresponding nucleotide (cm5Up) were isolated from brewer's yeast tRNAIII Arg or from the dodecanucleotide containing the anticodon. Their chromatographic and electrophoretic properties and their UV absorbing spectra were identical to that of the corresponding synthetic compounds. The gas chromatographic behavior and the mass spectrum of mcm5U obtained from tRNAIII Arg and of a synthetic sample were also identical ; the rare occurence of a thermal reciprocal bimolecular methyl-hydrogen transfer in the mass spectrometer ion source was observed. A mild alkaline treatment of tRNAIII Arg leads to the saponification of mcm5U into cm5U (within the tRNA), which can be again esterified in the presence of a yeast homogenate and (methyl-14C) S adenosylmethionine. The radioactivity was found in the mcm5U located in the wobble position of the anticodon of tRNAIII Arg. The presence of this odd nucleotide in that position could possibly restrict the codon-anticodon interaction of tRNAIII Arg.

Anticodon↗
PubMed2000

Hydrophobic ion pair formation between leuprolide and sodium oleate for sustained release from biodegradable polymeric microspheres.

Leuprolide acetate, an analogue of luteinizing hormone-releasing hormone (LH-RH), was hydrophobically ion paired with a long chain fatty acid, sodium oleate, in an aqueous solution. Solution behaviors of the complex formed between leuprolide and sodium oleate were investigated in terms of aqueous solubility, turbidity, particle size, and zeta potential as a function of molar ratio between the two species. It was found that with increasing the stoichiometric molar amounts of sodium oleate to leuprolide approached up to 2.5-3, the solution became gradually turbid with increasing particle sizes, indicating leuprolide precipitation as a result of hydrophobic ion pairing. On the other hand, beyond that critical molar ratio range, the solution turned into clear with much reduced particle size, indicative of micelle formation. The hydrophobically modified leuprolide-oleate complex was lyophilized and directly encapsulated within biodegradable poly(D, L-lactic-co-glycolic acid) (PLGA) microspheres via a single oil-in-water (O/W) emulsion method. Microsphere morphology, leuprolide release behavior, and polymer mass erosion profiles were examined in comparison to the PLGA microspheres prepared with free leuprolide.

Delayed-Action Preparations↗