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1.
Food Res Int ; 76(Pt 3): 637-644, 2015 Oct.
Article in English | MEDLINE | ID: mdl-28455047

ABSTRACT

In this study, the correlation between sensory attributes and the mechanical and acoustic properties of cocoa butter alternatives was elucidated. Needle penetration, cone penetration and compression tests were used to characterise mechanical properties and acoustic properties were evaluated by simultaneous texture and sound analyses. Results were correlated with a descriptive sensory evaluation. A significant correlation was found between hardness (needle penetration) and sensory hardness evaluated upon biting (r=0.91, p<0.05) and between Hencky strain (compression test) and the sensory toughness (r=0.94, p<0.05). In contrast, no significant correlation was found between brittleness (cone penetration) and the sensory brittleness. The use of different mechanical methods shed light on a complex rheological behaviour of fat which demonstrates the importance of not simply relying on results from penetration tests when evaluating fat texture. For instance, a hard fat was perceived very differently depending on the degree of elasticity. A significant correlation was found between sound pressure level (simultaneous sound and texture analyses) and the sensory evaluation of the sound intensity upon breakage (r=0.96 and 0.97, p<0.05). Both hardness and elasticity were found to be of great importance for the intensity of the sound emission i.e. a hard texture with a low degree of flexibility (less elastic) is more likely to provide a rapid energy release upon breakage and thus a high intensity sound emission.

2.
Brain Res ; 983(1-2): 23-35, 2003 Sep 05.
Article in English | MEDLINE | ID: mdl-12914963

ABSTRACT

Micro-machined neural prosthetic devices can be designed and fabricated to permit recording and stimulation of specific sites in the nervous system. Unfortunately, the long-term use of these devices is compromised by cellular encapsulation. The goals of this study were to determine if device size, surface characteristics, or insertion method affected this response. Devices with two general designs were used. One group had chisel-shaped tips, sharp angular corners, and surface irregularities on the micrometer size scale. The second group had rounded corners, and smooth surfaces. Devices of the first group were inserted using a microprocessor-controlled inserter. Devices of the second group were inserted by hand. Comparisons were made of responses to the larger devices in the first group with devices from the second group. Responses were assessed 1 day and 1, 2, 4, 6, and 12 weeks after insertions. Tissues were immunochemically labeled for glial fibrillary acidic protein (GFAP) or vimentin to identify astrocytes, or for ED1 to identify microglia. For the second comparison devices from the first group with different cross-sectional areas were analyzed. Similar reactive responses were observed following insertion of all devices; however, the volume of tissue involved at early times, <1 week, was proportional to the cross-sectional area of the devices. Responses observed after 4 weeks were similar for all devices. Thus, the continued presence of devices promotes formation of a sheath composed partly of reactive astrocytes and microglia. Both GFAP-positive and -negative cells were adherent to all devices. These data indicate that device insertion promotes two responses-an early response that is proportional to device size and a sustained response that is independent of device size, geometry, and surface roughness. The early response may be associated with the amount of damage generated during insertion. The sustained response is more likely due to tissue-device interactions.


Subject(s)
Brain/physiology , Microcomputers , Prostheses and Implants/adverse effects , Animals , Astrocytes/physiology , Brain Chemistry/physiology , Glial Fibrillary Acidic Protein/metabolism , Image Processing, Computer-Assisted , Immunohistochemistry , Male , Nanotechnology , Neuroglia/physiology , Prosthesis Implantation , Rats , Rats, Sprague-Dawley , Rats, Wistar , Surface Properties , Time Factors , Vimentin/metabolism
3.
J Biol Chem ; 276(17): 14204-11, 2001 Apr 27.
Article in English | MEDLINE | ID: mdl-11278927

ABSTRACT

Transient state kinetic studies indicate that substrate phosphorylation in protein kinase A is partially rate-limited by conformational changes, some of which may be associated with nucleotide binding (Shaffer, J., and Adams, J. A. (1999) Biochemistry 38, 12072-12079). To assess whether specific structural changes are associated with the binding of nucleotides, hydrogen-deuterium exchange experiments were performed on the enzyme in the absence and presence of ADP. Four regions of the protein are protected from exchange in the presence of ADP. Two regions encompass the catalytic and glycine-rich loops and are integral parts of the active site. Conversely, protection of probes in the C terminus is consistent with nucleotide-induced domain closure. One protected probe encompasses a portion of helix C, a secondary structural element that does not make any direct contacts with the nucleotide but has been reported to undergo segmental motion upon the activation of some protein kinases. The combined data suggest that binding of the nucleotide has distal structural effects that may include stabilizing the closed state of the enzyme and altering the position of a critical helix outside the active site. The latter represents the first evidence that the nucleotide alone can induce changes in helix C in solution.


Subject(s)
Adenosine Diphosphate/metabolism , Cyclic AMP-Dependent Protein Kinases/chemistry , Nucleotides/metabolism , Animals , Binding Sites , Catalysis , Deuterium/metabolism , Enzyme Activation , Escherichia coli/metabolism , Glycine/metabolism , Hydrogen/metabolism , Kinetics , Mice , Models, Molecular , Protein Binding , Protein Conformation , Protein Isoforms , Protein Structure, Secondary , Protein Structure, Tertiary , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Time Factors
4.
J Biol Chem ; 275(3): 1966-75, 2000 Jan 21.
Article in English | MEDLINE | ID: mdl-10636899

ABSTRACT

The first committed steps in the biosynthesis of the two cyanogenic glucosides linamarin and lotaustralin in cassava are the conversion of L-valine and L-isoleucine, respectively, to the corresponding oximes. Two full-length cDNA clones that encode cytochromes P-450 catalyzing these reactions have been isolated. The two cassava cytochromes P-450 are 85% identical, share 54% sequence identity to CYP79A1 from sorghum, and have been assigned CYP79D1 and CYP79D2. Functional expression has been achieved using the methylotrophic yeast, Pichia pastoris. The amount of CYP79D1 isolated from 1 liter of P. pastoris culture exceeds the amounts that putatively could be isolated from 22,000 grown-up cassava plants. Each cytochrome P-450 metabolizes L-valine as well as L-isoleucine consistent with the co-occurrence of linamarin and lotaustralin in cassava. CYP79D1 was isolated from P. pastoris. Reconstitution in lipid micelles showed that CYP79D1 has a higher k(c) value with L-valine as substrate than with L-isoleucine, which is consistent with linamarin being the major cyanogenic glucoside in cassava. Both CYP79D1 and CYP79D2 are present in the genome of cassava cultivar MCol22 in agreement with cassava being allotetraploid. CYP79D1 and CYP79D2 are actively transcribed, and production of acyanogenic cassava plants would therefore require down-regulation of both genes.


Subject(s)
Cytochrome P-450 Enzyme System/physiology , Glucosides/biosynthesis , Glucosides/metabolism , Manihot/enzymology , Nitriles/metabolism , Amino Acid Sequence , Blotting, Southern , Catalysis , Cells, Cultured , Cloning, Molecular , Cytochrome P-450 Enzyme System/genetics , Isoleucine/metabolism , Manihot/genetics , Models, Chemical , Molecular Sequence Data , Pichia/metabolism , Plants, Genetically Modified/genetics , Recombinant Proteins/metabolism , Sequence Homology, Amino Acid , Substrate Specificity , Valine/metabolism
5.
J Assoc Nurses AIDS Care ; 10(2): 55-65, 1999.
Article in English | MEDLINE | ID: mdl-10065410

ABSTRACT

The Well-Being Institute (WBI), a community-based nursing organization in Detroit, Michigan, has developed and put into practice innovative intervention and service delivery models to assist HIV-positive women who have a history of substance abuse and mental illness. These multiple-diagnosed women are known to have special problems and barriers to accessing health care. The service delivery model is based on "hyperlinking" women into hard-to-get health care appointment slots through nurses' personal contacts in health care clinics. The intervention model is the personalized nursing LIGHT model. This article describes the service delivery and intervention models and discusses outcomes of the WBI Women's Intervention Program in practice. The program locates HIV-positive, substance-abusing women; enrolls them in primary medical and mental health care; and helps retain them in health care. The results of the model in practice demonstrate its success in hyperlinking hard-to-reach and hard-to-serve HIV-positive women with health care and other needed services and resources. In addition, these multiple-diagnosed women have shown positive effects with respect to improved sense of well-being and decreased psychosocial distress.


Subject(s)
Community Health Nursing/organization & administration , Delivery of Health Care, Integrated/organization & administration , HIV Infections/complications , Health Services Accessibility/organization & administration , Mental Disorders/complications , Primary Health Care/organization & administration , Substance-Related Disorders/complications , Women's Health Services/organization & administration , Adult , Case Management/organization & administration , Community-Institutional Relations , Diagnosis, Dual (Psychiatry) , Female , HIV Infections/psychology , HIV Infections/therapy , Humans , Mental Disorders/psychology , Mental Disorders/therapy , Michigan , Models, Nursing , Nursing Evaluation Research , Program Evaluation , Referral and Consultation/organization & administration , Substance-Related Disorders/psychology , Substance-Related Disorders/therapy
6.
Biochem J ; 322 ( Pt 3): 815-22, 1997 Mar 15.
Article in English | MEDLINE | ID: mdl-9148754

ABSTRACT

To investigate structure-function relationships in plant chitinases, we have developed a heterologous expression system for the 26 kDa endochitinase from Hordeum vulgare L. (barley). Escherichia coli cells harbouring the gene in a T7 RNA polymerase-based expression vector synthesized completely insoluble recombinant protein under standard induction conditions at 37 degrees C. However, a concentration of soluble recombinant protein of approx. 15 mg/l was achieved by inducing bacteria at low temperature (15 degrees C). Recombinant endochitinase was purified to homogeneity and shown to be structurally and functionally identical to the seed protein. An average of three disulphide bonds are present in the recombinant enzyme, consistent with the number found in the natural form. The seed and recombinant proteins showed the same specific activity towards a high-molecular-mass substrate and exhibited similar anti-fungal activity towards Tricoderma reesei. Site-directed mutagenesis was used to replace residues that are likely to be involved in the catalytic event, based on structural similarities with lysozyme and on sequence alignments with related chitinases. The Glu67-->Gln mutation resulted in a protein with undetectable activity, while the Glu89-->Gln mutation yielded an enzyme with 0. 25% of wild-type specific activity. This suggests that two acidic residues are essential for catalytic activity, similar to the situation with many other glycosyl hydrolases. Examination of conserved residues stretching into the proposed substrate binding cleft suggests that Asn124 also plays an important functional role.


Subject(s)
Chitinases/genetics , Hordeum/genetics , Mutation , Chitinases/chemistry , DNA, Complementary/genetics , DNA, Complementary/isolation & purification , Gene Expression Regulation, Plant , Mutagenesis, Site-Directed , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Structure-Activity Relationship
7.
J Dairy Sci ; 79(2): 198-204, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8708081

ABSTRACT

The amino acid sequence of the bovine xanthine oxidoreductase was determined by cloning and sequencing cDNA clones encoding the enzyme. Partial amino acid sequence corresponding to 54% of the total sequence were also determined from purified bovine milk xanthine oxidoreductase, showing identity with the translated cDNA sequence. The cDNA of 4719 nucleotides included a 5' untranslated region of 96 nucleotides, an open reading frame encoding a xanthine oxidoreductase of 1332 amino acid residues, and a 3' untranslated region of 624 nucleotides including two polyadenylation signals and a poly (A) tail of 74 nucleotides. The identity between the amino acid sequence of the bovine xanthine oxidoreductase and xanthine oxidoreductase from mammalian species was 86 to 90%.


Subject(s)
Cattle , Cloning, Molecular , DNA, Complementary/genetics , Milk/chemistry , Xanthine Dehydrogenase/genetics , Xanthine Dehydrogenase/isolation & purification , Amino Acid Sequence , Animals , Base Sequence , DNA, Complementary/chemistry , Female , Mammary Glands, Animal/enzymology , Molecular Sequence Data , Sequence Analysis , Sequence Homology , Xanthine Dehydrogenase/chemistry
8.
Am J Drug Alcohol Abuse ; 19(3): 309-25, 1993.
Article in English | MEDLINE | ID: mdl-8213695

ABSTRACT

Two thousand thirty-three hospital emergency room (ER) patients who were current, active injecting drug users (IDUs) were voluntary participants in a pretest, posttest research project which utilized a nursing model, the Personalized Nursing LIGHT Model, as a counseling approach to decrease high-risk AIDS behaviors. The LIGHT Model works by directly improving well-being and thereby indirectly decreasing high-risk behaviors associated with AIDS. Addicts from an urban ER in each of three cities (Detroit, Michigan; Brooklyn, New York; and Baltimore, Maryland) were treated with teams consisting of nurses and indigenous outreach workers. Posttest data were gathered on 995 of the clients who received the Personalized Nursing LIGHT Model teaching and counseling intervention. In a posttest at least 3 months after the initial interview, these IDUs reported a significant increase in well-being, t(530) = -11.77; p < .001, and significant reductions in frequency of IV heroin use, z = -18.4; p < .001, IV cocaine use, z = -16.0; p < .001, and IV speedball use, z = -14.3; p < .001, as well as significant decreases in sharing of cookers (a type of drug-using equipment), z = -13.8; p < .001, and other high-risk behaviors associated with AIDS acquisition and transmission. At a second posttest, at least 6 months after the initial interview, these results were unchanged.


Subject(s)
Acquired Immunodeficiency Syndrome/prevention & control , Health Education , Substance Abuse, Intravenous/rehabilitation , Urban Population , Acquired Immunodeficiency Syndrome/psychology , Acquired Immunodeficiency Syndrome/transmission , Adolescent , Adult , Amphetamines , Cocaine , Counseling , Female , Health Knowledge, Attitudes, Practice , Heroin Dependence/complications , Heroin Dependence/psychology , Heroin Dependence/rehabilitation , Humans , Male , Middle Aged , Models, Nursing , Needle Sharing/adverse effects , Needle Sharing/psychology , Substance Abuse, Intravenous/complications , Substance Abuse, Intravenous/psychology , Substance-Related Disorders/complications , Substance-Related Disorders/psychology , Substance-Related Disorders/rehabilitation , Treatment Outcome
9.
Nurs Sci Q ; 5(2): 72-9, 1992.
Article in English | MEDLINE | ID: mdl-1584508

ABSTRACT

The consciousness rainbow is a heuristic designed to be used in nursing practice in conjunction with the personalized nursing practice model based on Rogers' science of unitary human beings (Rogers, 1970, 1990). The first phase in practicing nursing is pattern manifestation appraisal, followed by deliberative mutual patterning. This article presents pattern manifestation appraisal by describing patterns associated with "being," "well-being," and "not being." Clients who enter well-being via another dimension are encouraged to experience "being" in the present as a step toward genuine well-being.


Subject(s)
Consciousness , Health Status , Human Development , Models, Nursing , Existentialism , Humans
10.
Int J Addict ; 24(8): 739-54, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2606585

ABSTRACT

The purpose of this research was to describe a group of chemically dependent females who were involved with the criminal justice system and note if they reported histories of physical/sexual abuse. Data for this study were obtained from Andersen's 1986 research project funded by the Michigan Department of Corrections and Wayne State University. The findings showed that 19.7% reported histories of sexual abuse and that 27% reported histories of physical/sexual abuse prior to incarceration. These findings suggest a need for a sexual assessment tool and for further research on the relationships of sexual/physical abuse and chemical dependency.


Subject(s)
Alcoholism/psychology , Child Abuse, Sexual/psychology , Child Abuse/psychology , Substance-Related Disorders/psychology , Adolescent , Adult , Child , Female , Humans , Life Change Events , Middle Aged , Risk Factors
11.
Nurs Sci Q ; 2(3): 120-30, 1989.
Article in English | MEDLINE | ID: mdl-2779893

ABSTRACT

The Personalized Nursing LIGHT model is a prescriptive model for nursing. It is a model for nursing practice derived from a synthesis of Aristotle's theory of ethics and Martha E. Rogers' science of unitary human beings. The LIGHT model provides a mechanism for nurses to assist clients to improve their sense of well-being. The authors believe that improving well-being is the focus of nursing. Using principles synthesized from Aristotle and Rogers, clients are encouraged to use their talents in the pursuit of well-being and happiness in an increasingly complex world.


Subject(s)
Models, Theoretical , Nursing Theory , Ethics, Nursing , Humans , Nurse-Patient Relations , Philosophy
12.
Int J Addict ; 21(1): 105-22, 1986 Jan.
Article in English | MEDLINE | ID: mdl-3486836

ABSTRACT

One hundred and fifty five drug-dependent women in an urban hospital emergency room in Detroit, Michigan, were the subjects for this 3-year exploratory field study. Subjects were women who told the emergency room staff that while they wanted assistance with their presenting health problems, they wanted no assistance with their drug addiction. The women were randomly assigned to either the experimental or control study group. Both groups received a pretest in the emergency room, a posttest between 8 and 12 weeks after their emergency room visit, and a follow-up test 6 months after the posttest. In addition, the experimental women were seen by project nurses, primarily in their homes, for a maximum of eight visits on a once-a-week basis. The experimental women were treated using "Personalized Nursing," a nursing intervention model, which focused on providing assistance for client-identified concerns. It was hypothesized that interaction with the Personalized Nursing Intervention Model would be associated with: a decrease in daily drug cost and a decrease in perceived stress. Results show that while there were no differences between the study groups at the pretest interview, the experimental group reported a lower daily drug cost (F(1, 95) = 2.90; p = 0.09), a lower daily heroin cost (U = 165; p = .01), less perceived stress (F(1, 84) = 3.00; p = .09) and emotional distress (F(1, 83) = 3.70; p = .06) than control subjects at the 8-week posttest. The experimental subjects also reported less perceived stress (t(65) = -2.35; p = .02) at 6-month follow-up than control subjects. It was found that results could be improved if members of the experimental clients' social networks were treated simultaneously and if project nurses were correctly utilizing the model. Implications for substance abuse treatment programs are discussed. The encouraging results of this exploratory study warrant follow-up and replication.


Subject(s)
Emergency Service, Hospital , Substance-Related Disorders/nursing , Adaptation, Psychological , Adult , Alcoholism/nursing , Female , Heroin Dependence/nursing , Hospitals, Urban , Humans , Marijuana Abuse/nursing , Michigan , Nurse-Patient Relations , Social Support , Stress, Psychological/complications , Substance-Related Disorders/psychology
13.
NIDA Res Monogr ; 58: 67-82, 1985.
Article in English | MEDLINE | ID: mdl-3929127

ABSTRACT

The study indicates that nurses can affect stress and drug use in addicted women. At the 8-week posttest, daily drug cost and daily heroin costs had gone down for the experimental group. However, at the 6-month posttest, daily drug cost and daily heroin cost for the experimental group increased, although it did not reach its initial pre-intervention levels. The increase in drug costs at 6-month followup is probably a result of the lack of nursing intervention after the 8-week period. Interestingly, both the drug costs and heroin costs of the control group went down at 6 months. In other words, the control group decreased use also, only at a slower pace. What accounted for this decrease in use by the control group at 6 months? Several speculations are offered. The single Personalized Nursing Intervention counseling in the ER may have had an impact on the client. Controls who had had the single intervention in the ER were receptive to followup and were easily found. (Originally the single intervention in the ER was not part of the design. However, about 20 clients who had not had Personalized Nursing Intervention in the ER but who just answered the initial questionnaire were never found for followup. Because of the followup and ethical considerations, project staff members instituted the single ER intervention.) Another speculation is that of "burnout," a phenomenon that can be seen in both experimental and control groups. The mean age of the total population was 28.5, number of times arrested was 7.25, and age at first drug use was 16. It appeared that the following factors evoked a desire for change in these women: 1) leading a drug lifestyle for so many years, 2) the approach of age 30, 3) entrance into adolescence of their own children, and 4) the ER episode. Personalized Nursing Intervention could be considered a catalyst toward lifestyle change. Examination of daily drug cost and the Ireton emotional distress score showed trends indicating that the experimentals with network participation made larger gains than the control group or experimentals without networks. Further study on the use of client networks in treatment is indicated.


Subject(s)
Emergency Service, Hospital , Home Care Services , Substance-Related Disorders/nursing , Adult , Female , Humans , Life Style , Referral and Consultation , Self Concept , Social Support , Substance-Related Disorders/psychology
14.
Nursing ; 7(1): 16, 1977 Jan.
Article in English | MEDLINE | ID: mdl-583710
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