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1.
Palliat Support Care ; 20(4): 582-592, 2022 08.
Article in English | MEDLINE | ID: mdl-34183091

ABSTRACT

OBJECTIVE: There is growing recognition of the importance of increasing preparedness for and the provision of palliative care in humanitarian crises. The primary objective of this review is to interpret the existing literature on culture and palliative care to query the recommendation that humanitarian healthcare providers, teams, and organizations integrate palliative care into their practice in ways that are attentive to and respectful of cultural differences. METHODS: A critical interpretive synthesis was applied to a systematic literature review guided by the PRISMA framework. Analysis was based on directed data extraction and was team based, to ensure rigor and consistency. RESULTS: In total, 112 articles covering 51 countries and 9 major worldviews met inclusion criteria. This literature describes culture as it influences perspectives on death and dying, expectations of palliative care, and challenges to providing culturally sensitive care. A key pattern highlighted in articles with respect to the culture and palliative care literature is that culture is invoked in this literature as a sort of catch-all for non-white, non-Christian, indigenous practices, and preferences for palliative care. It is important that humanitarian healthcare providers and organizations aiming to enact their commitment of respect for all persons through attention to potential culturally specific approaches to pain management, suffering, and dying in specific crisis settings do so without reproducing Othering and reductionistic understandings of what culturally sensitive care in humanitarian crises settings involves. SIGNIFICANCE OF RESULTS: This paper clarifies and unpacks the diverse influences of culture in palliative care with the goal of supporting the preparedness and capacity of humanitarian healthcare providers to provide palliative care. In doing so, it aids in thinking through what constitutes culturally sensitive practice when it comes to palliative care needs in humanitarian crises. Providing such care is particularly challenging but also tremendously important given that healthcare providers from diverse cultures are brought together under high stress conditions.


Subject(s)
Hospice and Palliative Care Nursing , Palliative Care , Culturally Competent Care , Health Personnel , Humans , Pain Management , Palliative Care/methods
2.
Microbiol Resour Announc ; 8(20)2019 May 16.
Article in English | MEDLINE | ID: mdl-31097509

ABSTRACT

Beatrix, Carthage, Daegal, Dulcie, Fancypants, Fenn, Inca, Naira, and Robyn are newly isolated bacteriophages capable of infecting Mycolicibacterium smegmatis mc2 155. We discovered, sequenced, and annotated these New Zealand bacteriophages. These phages illustrate that New Zealand harbors a selection of the highly diverse and distributed mycobacteriophage clusters found globally.

3.
J Phys Chem A ; 123(13): 2780-2788, 2019 Apr 04.
Article in English | MEDLINE | ID: mdl-30811199

ABSTRACT

We report on one-color experiments near 214 nm involving the photodissociation of jet-cooled OCS to produce high rotational states (40 < J < 80) of CO (X 1Σ+, v = 0, 1) which were then ionized by 2+1 resonance-enhanced multiphoton ionization via the E 1Π state. The nominally forbidden Q-branch of the two-photon E 1Π-X 1Σ+ transition is observed with intensity comparable to the allowed R-branch. The bright character of the high- J Q-branch lines can be described quantitatively as intensity borrowing due to mixing of the E 1Π and C 1Σ+ states, using J-dependent mixing coefficients extrapolated from the observed Λ-doubling in the lower rotational levels of the E state. In addition to the significant enhancement of Q-branch intensities above the values predicted by conventional two-photon line strengths for a 1Π-1Σ+ transition, the high- J lines of the R- and P-branches appear to be suppressed in intensity by approximately a factor of 3 compared to the unperturbed low- J line strengths, most likely due to perturbations associated with a 1Σ- state. The E-state rotational term values for J < 80, v = 0 derived from the present spectra agree within our measurement and calibration uncertainties with the extrapolations based on the molecular constants previously derived from rotational levels with J < 50. The E-X transition is attractive for future application to photodissociation dynamics and rotational polarization measurements of CO photofragments, with convenient access to state-selective probing on multiple rotational branches, which exhibit different sensitivity to fragment alignment.

4.
J Water Health ; 16(6): 893-903, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30540263

ABSTRACT

Indigenous communities in Canada are over-represented with respect to poor water quality and water advisories. To date, approaches to solve this water crisis have been founded in the Western Science (WS) context with little to no consultation or dialogue with those communities most impacted, and without regard for culture. A literature review was undertaken to: (i) document Indigenous Knowledge (IK), and perspectives regarding water and (ii) to identify current local water security tools utilized by Indigenous communities. The aim is to provide sound evidence regarding the value of ownership and leadership by Indigenous communities in the context of current and appropriate resources available to (re)claim these roles. Solutions must remain consistent with, and founded upon, traditional Indigenous worldviews and cultural values to ensure sustainable water security. Literature reviewed from the past ten years revealed one overarching creation theme with three water-specific themes in Indigenous communities; namely, water from natural sources, water as a life-giving entity, and water and gender. Ultimately, there needs to be a new framing of local water security with the development of tools which engage IK and WS in order to assess local water security and appropriately inform interventions, policies, regulations and legislation.


Subject(s)
Population Groups , Water Quality , Water Supply/statistics & numerical data , Canada , Humans , Water
5.
J Phys Chem A ; 116(16): 4069-73, 2012 Apr 26.
Article in English | MEDLINE | ID: mdl-22452330

ABSTRACT

We present laboratory measurements of H(2)O-broadened (16)O(2) A-band (b(1)Σ(g)(+) ← X(3)Σ(g)(-)(0,0)) absorption spectra acquired with a laser-based photoacoustic spectroscopy method. This absorption band is widely used in a variety of high-precision atmospheric remote sensing applications. We report H(2)O broadening parameters for six of the strongest transitions in this band, and we show that these measured values are nominally 1.5-2 times greater than the corresponding air-broadening parameters. Simulations of atmospheric transmission spectra in the O(2) A-band that incorporate our measured H(2)O broadening parameters indicate that H(2)O present at concentrations typically found in the Earth's atmosphere can influence the column-integrated transmission relative to the dry air case. Further, because of spatial and seasonal variations in humidity, failure to account for the enhanced H(2)O pressure broadening effects can lead to concomitant biases in atmospheric O(2) A-band retrievals of quantities such as surface pressure and path length in greenhouse gas retrievals.


Subject(s)
Atmosphere/chemistry , Oxygen/chemistry , Water/chemistry
6.
East Afr J Public Health ; 8(2): 103-11, 2011 Jun.
Article in English | MEDLINE | ID: mdl-22066295

ABSTRACT

OBJECTIVE: Almost 1 billion individuals lack access to improved water supplies, with 2.6 billion lacking adequate sanitation. This leads to the propagation of multiple waterborne diseases. The objective of this study was to explore local knowledge, attitudes and practices to understand the mechanisms and pre-conditions for sustainable uptake and use of these facilities. METHODS: Data collection took place in a rural Kenyan community in September 2009. A qualitative approach was taken, with 4 focus groups and 25 in-depth interviews conducted. Participant characteristics varied by age, gender, education, marital status, employment and community standing. RESULTS: Few participants reported current access to improved water and sanitation facilities. Though they expressed desire for latrines and water sources, barriers including lack of funds and social capital, decrease the ability for installation. Participants understood that there was a link between the quality of water and their health, however, perceived benefits of current contaminated sources outweigh the potential health impacts and proliferate their continued use. CONCLUSION(S): While water-health links are understood to varying degrees within the community, contextual (physical environment), compositional (individual) and collective (community) factors interact to influence health. Community challenges, such as lack of unity, lack of education and lack control were identified as the main barriers to initiating change, despite a desire for increased access to safe water and sanitation.


Subject(s)
Health Knowledge, Attitudes, Practice , Rural Health , Sanitation , Water Supply , Drinking Water , Female , Focus Groups , Health Surveys , Humans , Hygiene , Male , Public Health , Qualitative Research , Residence Characteristics , Rural Population , Socioeconomic Factors , Surveys and Questionnaires
7.
J Phys Chem A ; 115(47): 13804-10, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-22013917

ABSTRACT

Remote sensing of CO(2) requires high-fidelity reference data of spectral line parameters to be successful. The 6360 cm(-1) region is commonly used by satellites, field campaigns, and point-source gas sensors because it contains well-characterized and relatively isolated transitions of appropriate line strengths for atmospheric applications. However, the presence of gases other than CO(2), N(2), and O(2) can be a source of uncertainty for atmospheric measurements. Near 6360 cm(-1), there are numerous H(2)O and HDO transitions. Water makes up approximately 1-4% of Earth's lower atmosphere and can interfere with remote sensing measurements by (1) appearing as a direct spectral interference or (2) acting as a foreign broadener for CO(2) lines. The primary goal of this work was to quantify H(2)O broadening of CO(2) through precision spectroscopy measurements on the R16e transition at 6359.967 cm(-1) and its two nearest neighbors. A secondary goal was to assess the accuracy of H(2)O reference line parameters in the HITRAN 2008 database for spectrally removing typical levels of moisture from air samples containing approximately 400 ppm of CO(2).


Subject(s)
Carbon Dioxide/chemistry , Water/chemistry , Spectroscopy, Near-Infrared
8.
Epidemiol Infect ; 139(11): 1774-83, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21134324

ABSTRACT

The lack of high-quality health information for accurately estimating burdens of disease in some Aboriginal populations is a challenge for developing effective and relevant public health programmes and for health research. We evaluated data from a health registry system that captured patient consultations, provided by Labrador Grenfell Health (Labrador, Canada). The goal was to evaluate the registry's utility and attributes using modified CDC guidelines for evaluating surveillance systems. Infectious gastrointestinal illness data were used as a reference syndrome to determine various aspects of data collection and quality. Key-informant interviews were conducted to provide information about system utility. The study uncovered limitations in data quality and accessibility, resulting in region-specific recommendations including conversion to an electronic system. More generally, this study emphasized how a systematic and standardized evaluation of health registry systems can help address challenges to obtaining quality health data in often remote areas where many Aboriginal communities are found.


Subject(s)
Electronic Health Records , Inuit/statistics & numerical data , Population Surveillance/methods , Registries , Canada/epidemiology , Female , Gastrointestinal Diseases/epidemiology , Gastrointestinal Diseases/ethnology , Humans , Male , Newfoundland and Labrador
9.
Anaesth Intensive Care ; 38(1): 50-4, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20191777

ABSTRACT

Laryngeal mask airways (LMA) are commonly used in paediatric anaesthesia. A well-placed LMA should provide a direct view of the vocal cords facilitating bronchoscopy or fibreoptic intubation. The aim of this audit was to assess the bronchoscopic view of the glottis obtained through an LMA with regard to its size. We prospectively assessed the position of LMAs in relation to the glottic aperture in 350 children (zero to seven years) undergoing elective fibreoptic examination of the upper and/or lower airways. Following induction of anaesthesia and positioning of the LMA, a fibreoptic evaluation of the view of the glottis was performed (complete, partial or no visualisation). Chest movement on manual ventilation was judged as good in the majority of patients and adequate for the remainder. No overt signs of airway obstruction were noted in any patient. However, a complete view of the glottic aperture was present in only 50% of size 1 LMAs, 57.5% of size 1.5, 72.7% of size 2 and 77.8% of size 2.5. The epiglottis impinged on the LMA opening, partially obstructing the view of the glottis in 36.3% of size 1 LMAs, 31.5% of size 1.5, 21% of size 2 and 17.8% of size 2.5. In 13.7% of size 1 LMAs, 11% of size 1.5, 6.3% of size 2 and 4.4% of size 2.5, the epiglottis was completely downfolded, obstructing the view of the glottic aperture. The findings indicate that even if ventilation is judged as adequate, smaller paediatric LMAs are more commonly associated with suboptimal anatomical positioning with partial obstruction of the glottic aperture than larger LMAs, and therefore may require repositioning more often.


Subject(s)
Laryngeal Masks , Larynx/anatomy & histology , Anesthesia, Inhalation , Anesthesia, Intravenous , Child , Child, Preschool , Equipment Design , Female , Glottis/anatomy & histology , Humans , Infant , Infant, Newborn , Intubation, Intratracheal/instrumentation , Intubation, Intratracheal/methods , Male , Optical Fibers , Prospective Studies , Quality Assurance, Health Care , Respiration, Artificial
10.
Anaesthesia ; 64(5): 527-31, 2009 May.
Article in English | MEDLINE | ID: mdl-19413823

ABSTRACT

Hyperinflation of the laryngeal mask airway cuff may exert high pressure on pharyngeal and laryngeal structures. In vitro data show that high intra cuff pressures may occur when inflated to only 30% of the manufacturer's recommended maximum inflation volume. We prospectively assessed the pressure volume curves of paediatric sized laryngeal mask airways (size 1-3) in 240 consecutive children (0-15 years). Following laryngeal mask airway insertion the cuff was inflated with 1-ml increments of air up to the maximum recommended by the manufacturer. After each ml cuff pressure was measured. At the end all cuff pressures were adjusted to 55 cmH(2)O. The maximum recommended volume resulted in high intracuff pressures in all laryngeal mask airway brands and sizes studied. Approximately half the maximum volume produced a cuff pressure > or = 60 cmH(2)O. This occurred in all brands and all sizes studied. We recommend that cuff manometers should be used to guide inflation in paediatric laryngeal mask airways.


Subject(s)
Air Pressure , Laryngeal Masks , Adolescent , Anesthesia, General , Body Weight , Child , Child, Preschool , Equipment Design , Female , Humans , Infant , Infant, Newborn , Male , Prospective Studies
12.
Depress Anxiety ; 14(4): 214-8, 2001.
Article in English | MEDLINE | ID: mdl-11754128

ABSTRACT

Treatment of obsessive-compulsive disorder has focused almost exclusively on symptom reduction; however, deficits in social functioning and quality of life of individuals with this disorder may contribute more to their "burden," suffering, and disability. To gauge the significance of social dysfunction and quality of life of persons with obsessive-compulsive disorder (OCD), we made comparisons with a group of persons with schizophrenia matched for age and gender. Thirty-one patients with OCD participating in a partial hospital treatment program were compared with 68 schizophrenic outpatients participating in a day rehabilitation program. The Independent Living Skills Survey (ILSS) and Lehman Quality of Life Scale (QOL) were administered before and after treatment for both cohorts. QOL scores were significantly lower for the OCD patients both before and after treatment, but improved significantly during treatment. OCD and schizophrenic patients had similar scores on almost every domain of the ILSS at pretreatment. The OCD patients improved significantly on many of the domains of social and independent living skills as a result of treatment and acquired significantly greater skills by post-treatment than did their counterparts with schizophrenia; however, the performance of social and independent living skills by OCD patients remained less than satisfactory even in domains where they improved. In the areas of job and leisure skills, there were significant group-by-time interactions. We concluded that patients with severe OCD and patients with schizophrenia are equally socially impaired. However, OCD patients experience greater significant functional improvement with multimodal treatment.


Subject(s)
Obsessive-Compulsive Disorder/psychology , Quality of Life , Schizophrenic Psychology , Social Adjustment , Activities of Daily Living/psychology , Adult , Cohort Studies , Day Care, Medical , Female , Humans , Leisure Activities , Male , Obsessive-Compulsive Disorder/diagnosis , Obsessive-Compulsive Disorder/rehabilitation , Outcome Assessment, Health Care , Rehabilitation, Vocational , Schizophrenia/diagnosis , Schizophrenia/rehabilitation
13.
Biochem J ; 359(Pt 3): 715-20, 2001 Nov 01.
Article in English | MEDLINE | ID: mdl-11672447

ABSTRACT

The absolute conservation of tryptophan at position 59 in cytochrome c is related to the unique chemical nature of its indole moiety. The indole side chain of Trp-59 possesses three salient features: bulk, hydrophobicity and the ability of its indole nitrogen to act as a hydrogen-bond donor. Crystallographic evidence identifies the indole nitrogen of Trp-59 as having a stabilizing hydrogen-bonding interaction with the buried carboxylate group of haem propionate 7. Side-chain bulk is also likely to be important because a Phe or Leu residue can replace Trp to give an at least partly functional protein, whereas the smaller Gly or Ser cannot. Semisynthetic analogues were designed to test the importance of the side-chain features of tryptophan by using a recently developed method for stereoselective fragment religation in yeast cytochrome c. Three yeast iso-1 cytochrome c analogues were produced in which Trp-59 was replaced by a non-coded amino acid: p-iodophenylalanine, beta-(3-pyridyl)-alanine or beta-(2-naphthyl)-alanine. Replacement of Trp-59 with these non-coded amino acids allows the reasons for its conservation to be analysed, because they vary with respect to size, hydrophobicity and hydrogen-bond potential. Our results show that decreasing the bulk and hydrophobicity of the side chain at position 59 has a profound but different impact on physicochemical and biological parameters from those of abolishing hydrogen-bond donor potential. This suggests that Trp-59 has both a local and a global stability effect by solvating a buried charge and by having a key role in the packing of the cytochrome c hydrophobic core.


Subject(s)
Cytochrome c Group/chemistry , Cytochrome c Group/genetics , Indoles/chemistry , Tryptophan/chemistry , Cytochrome c Group/metabolism , Models, Molecular , Molecular Structure , Oxidation-Reduction , Oxidoreductases/metabolism , Protein Structure, Tertiary , Saccharomyces cerevisiae/chemistry , Saccharomyces cerevisiae/enzymology
14.
Exp Brain Res ; 139(4): 448-53, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11534869

ABSTRACT

There is strong evidence that the predominant pathway of the long-latency stretch reflex for flexor pollicis longus crosses the motor cortex. This reflex response is diminished during active thumb movements. We tested the hypothesis that this could be due to a decrease in the excitability of the transcortical component during movement. During isometric, concentric and eccentric thumb movements, transcranial magnetic stimulation (TMS) of the motor cortex was given at a time when the reflex signal was traversing the motor cortex. TMS was also given earlier in separate runs when the signal was traversing the spinal cord under each of the three contractile conditions. The electromyogram was analysed for non-linear summation between stretch responses and the potential evoked by the cortical stimulus. The response to TMS alone was uniform across the three types of contraction, and the lack of cortical involvement in the short-latency reflex was confirmed. The TMS-evoked response summed in a non-linear manner with the long-latency reflex response, confirming that the excitability of the motor cortex was increased as the reflex signal passed through it. The long-latency response was markedly depressed during isotonic compared with isometric contractions. However, the non-linear summation was not greater during the isometric contractions. Thus, the depressed reflex responses during isotonic movements do not stem from reduced motor cortical responsiveness or afferent input to the transcortical pathway, and may instead reflect modulation of cutaneous reflexes during isotonic contractions.


Subject(s)
Cerebral Cortex/physiology , Movement/physiology , Muscle, Skeletal/physiology , Reflex, Stretch/physiology , Thumb/physiology , Adolescent , Adult , Electromagnetic Fields , Electromyography , Female , Humans , Isometric Contraction/physiology , Isotonic Contraction/physiology , Male , Middle Aged , Muscle, Skeletal/innervation , Thumb/innervation
15.
Biophys J ; 81(4): 2331-8, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11566802

ABSTRACT

This communication introduces a simple method to determine the pKs of microscopic ionizations from complex titration curves. We used this approach to study the alkaline transition (pH-dependent ligand exchange) of mitochondrial cytochrome c. The linearization of titration curves permitted resolution of two to three limiting microscopic ionizations. By combining these data with studies of the temperature dependence of ligand-exchange equilibria, we found evidence that the alkaline transition comprises two chemically distinct processes: the deprotonation of the alternative ligands and the break of the iron-methionine ligation bond. We also noted that, in the horse and untrimethylated S. cerevisiae iso-1 cytochromes c, the permissible deprotonation of the epsilon-amino group of Lys(72) allows formation of an alkaline isomer at lower pH, with lesser stability, which leads to hysteresis in the titration curves. The linearization of the titration curves for different cytochromes c thus brings insight on the microscopic contributions to conformational stability.


Subject(s)
Cytochrome c Group/metabolism , Cytochromes c , Lysine/metabolism , Mitochondria/enzymology , Saccharomyces cerevisiae Proteins , Animals , Arginine/metabolism , Colon, Sigmoid , Horses/metabolism , Hydrogen-Ion Concentration , Iron/metabolism , Isomerism , Kinetics , Methionine/metabolism , Mutagenesis, Site-Directed , Protein Conformation , Saccharomyces cerevisiae/metabolism , Titrimetry
16.
Biochem Cell Biol ; 79(4): 517-24, 2001.
Article in English | MEDLINE | ID: mdl-11527221

ABSTRACT

Cytochrome c is a small electron-transport protein whose major role is to transfer electrons between complex III (cytochrome reductase) and complex IV (cytochrome c oxidase) in the inner mitochondrial membrane of eukaryotes. Cytochrome c is used as a model for the examination of protein folding and structure and for the study of biological electron-transport processes. Amongst 96 cytochrome c sequences, residue 85 is generally conserved as either isoleucine or leucine. Spatially, the side chain is associated closely with that of the invariant residue Phe82, and this interaction may be important for optimal cytochrome c activity. The functional role of residue 85 has been examined using six site-directed mutants of Saccharomyces cerevisiae iso-1 cytochrome c, including, for the first time, kinetic data for electron transfer with the principle physiological partners. Results indicate two likely roles for the residue: first, heme crevice resistance to ligand exchange, sensitive to both the hydrophobicity and volume of the side chain; second, modulation of electron-transport activity through maintenance of the hydrophobic character of the protein in the vicinity of Phe82 and the exposed heme edge, and possibly of the ability of this region to facilitate redox-linked conformational change.


Subject(s)
Cytochrome c Group/metabolism , Cytochromes c , Leucine/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/enzymology , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Cytochrome c Group/chemistry , Cytochrome c Group/genetics , Kinetics , Models, Molecular , Mutagenesis, Site-Directed , Protein Conformation , Saccharomyces cerevisiae Proteins/chemistry , Saccharomyces cerevisiae Proteins/genetics
17.
Schizophr Res ; 50(1-2): 105-19, 2001 May 30.
Article in English | MEDLINE | ID: mdl-11378319

ABSTRACT

This paper reports the psychometric characteristics of a measure that assesses the treatment outcomes of individuals with serious and persistent mental illness. Unlike other outcome measures, this one is designed to be embedded in the clinical process of planning and evaluating treatment. It collects individualized data, structures how the data are used to plan and evaluate a client's treatment, and produces aggregate information relevant for research and program purposes. Two parallel versions were developed: one for the client's self-report, and one for an informant's report. The self-report measure was administered by peer-interviewers to 244 community interviewees, and by inpatient peer-interviewers to 93 inpatient interviewees. The community interviewees also completed the BASIS-32 and SF-36. Informants for 103 of the community interviewees completed the informant version of the measure, and the CCAR. Inpatient staff completed the informant version for 161 inpatient residents without regard for matching the 93 inpatient interviewees. The two versions had acceptable internal consistency, test--retest, and interrater reliabilities. Correlations of the community interviewees' and informants' results with the BASIS-32, SF-36, and CCAR provided evidence of convergent and discriminant validity, as did contrasts between community and inpatients interviewees. The usefulness of the instrument for clinical, program and research purposes is discussed, with emphasis on the characteristics that enhance its value in clinical practice --- assessment of meaningful outcomes, operationalization of client empowerment, comprehensiveness, easy administration, and continuity across time and provider. Also discussed is a computer-based program to summarize and present the results in a rapid, clinically meaningful manner.


Subject(s)
Community Mental Health Services/organization & administration , Consumer Advocacy , Health Planning , Schizophrenia/therapy , Activities of Daily Living , Adult , Female , Humans , Male , Middle Aged , Program Evaluation , Psychometrics/statistics & numerical data , Quality of Life , Reproducibility of Results , Schizophrenia/diagnosis , Severity of Illness Index , Social Adjustment , Surveys and Questionnaires , Treatment Outcome
18.
J Biol Chem ; 276(31): 28814-8, 2001 Aug 03.
Article in English | MEDLINE | ID: mdl-11375991

ABSTRACT

The effect of the protein matrix on the standard potential of a buried redox center has been investigated by using a selection of mutants and chemical derivatives in Saccharomyces cerevisiae cytochrome c isoform 1. Assuming only local structural perturbation and no alteration of the iron-ligation chemistry, Delta E(m)(0)' can be regarded as a measure of the difference in polypeptide solvation of the heme charge, which reflects the dielectric properties of the protein. The evaluation of an apparent dielectric constant (U(exp)/U(theo)) yields variable, and sometimes even negative, values if U(exp) = Delta G(0)redox. However, some consistent result are observed if U(exp) = Delta H(0)redox, with a measured epsilon(Delta Delta)(H)(redox) = 19 +/- 6. The variability is thus attributed to an entropic factor (epsilon(Delta Delta)(S)(redox)) that is investigated using a series of substitutions of Asn(52) and/or Tyr(67). In double mutants Y67F/N52I Y67F/N52V, where most of the hydrogen bond network in the heme crevice is eliminated, Delta S(redox) compares to the wild type. This indicates that a fully consistent hydrogen bond network has a similar polarizability as an apolar matrix. We therefore argue that the variability in net dielectric susceptibility arises from conformational polarizability, a factor that is not a function of atomic properties and coordinates and is therefore hard to predict using conventional physical relationships.


Subject(s)
Cytochrome c Group/chemistry , Amino Acid Substitution , Circular Dichroism , Computer Graphics , Cytochrome c Group/metabolism , Entropy , Iron , Kinetics , Models, Molecular , Mutagenesis, Site-Directed , Oxidation-Reduction , Point Mutation , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Static Electricity , Thermodynamics
19.
J Trauma ; 50(3): 415-24; discussion 425, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11265020

ABSTRACT

BACKGROUND: Variability and logistic complexity of mechanical ventilatory support of acute respiratory distress syndrome, and need to standardize care among all clinicians and patients, led University of Utah/LDS Hospital physicians, nurses, and engineers to develop a comprehensive computerized protocol. This bedside decision support system was the basis of a multicenter clinical trial (1993-1998) that showed ability to export a computerized protocol to other sites and improved efficacy with computer- versus physician-directed ventilatory support. The Memorial Hermann Hospital Shock Trauma intensive care unit (ICU) (Houston, TX; a Level I trauma center and teaching affiliate of The University of Texas Houston Medical School) served as one of the 10 trial sites and recruited two thirds of the trauma patients. Results from the trauma patient subgroup at this site are reported to answer three questions: Can a computerized protocol be successfully exported to a trauma ICU? Was ventilator management different between study groups? Was patient outcome affected? METHODS: Sixty-seven trauma patients were randomized at the Memorial Hermann Shock Trauma ICU site. "Protocol" assigned patients had ventilatory support directed by the bedside respiratory therapist using the computerized protocol. "Nonprotocol" patients were managed by physician orders. RESULTS: Of the 67 trauma patients randomized, 33 were protocol (age 40 +/- 3; Injury Severity Score [ISS] 26 +/- 3; 73% blunt) and 34 were nonprotocol (age 38 +/- 2; ISS 25 +/- 2; 76% blunt). For the protocol group, the computerized protocol was used 96% of the time of ventilatory support and 95% of computer-generated instructions were followed by the bedside respiratory therapist. Outcome measures (i.e., survival, ICU length of stay, morbidity, and barotrauma) were not significantly different between groups. Fio2 > or = 0.6 and Pplateau > or = 35 cm H2O exposures were less for the protocol group. CONCLUSION: A computerized protocol for bedside decision support was successfully exported to a trauma center, and effectively standardized mechanical ventilatory support of trauma-induced acute respiratory distress syndrome without adverse effect on patient outcome.


Subject(s)
Clinical Protocols/standards , Critical Care/standards , Multiple Trauma/complications , Positive-Pressure Respiration/methods , Positive-Pressure Respiration/standards , Respiratory Distress Syndrome/etiology , Respiratory Distress Syndrome/therapy , Adult , Blood Gas Analysis , Decision Support Techniques , Female , Humans , Injury Severity Score , Length of Stay/statistics & numerical data , Male , Morbidity , Multiple Trauma/classification , Multiple Trauma/therapy , Outcome Assessment, Health Care , Point-of-Care Systems/standards , Positive-Pressure Respiration/adverse effects , Practice Guidelines as Topic/standards , Respiratory Distress Syndrome/metabolism , Respiratory Distress Syndrome/mortality , Survival Analysis , Trauma Centers
20.
Biochem Cell Biol ; 79(1): 83-91, 2001.
Article in English | MEDLINE | ID: mdl-11235919

ABSTRACT

Cytochrome c is a small electron transport protein found in the intermembrane space of mitochondria. As it interacts with a number of different physiological partners in a specific fashion, its structure varies little over eukaryotic evolutionary history. Two highly conserved residues found within its sequence are those at positions 13 and 90 (numbering is based on the standard horse cytochrome c); with single exceptions, residue 13 is either Lys or Arg, and residue 90 is either Glu or Asp. There have been conflicting views on the roles to be ascribed to these residues, particularly residue 13, so the functional properties of a number of site-directed mutants of Saccaromyces cerevisiae iso-1 cytochrome c have been examined. Results indicate that the two residues do not interact specifically with each other; however, residue 13 (Arg) is likely to be involved in interactions between cytochrome c and other electrostatically oriented physiological partners (intermolecular), whereas residue 90 (Asp) is involved in maintaining the intrinsic structure and stability of cytochrome c (intramolecular). This is supported by molecular dynamics simulations carried out for these mutants where removal of the negative charge at position 90 leads to significant shifts in the conformations of neighboring residues, particularly lysine 86. Both charged residues appear to exert their effects through electrostatics; however, biological activity is significantly more sensitive to substitutions of residue 13 than of residue 90.


Subject(s)
Cytochrome c Group/metabolism , Animals , Chromatography, Ion Exchange , Cytochrome c Group/chemistry , Hydrogen-Ion Concentration , Models, Molecular , Rats , Saccharomyces cerevisiae/enzymology , Static Electricity , Structure-Activity Relationship
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