Mechanism-Based Strategies for Structural Characterization of Radical SAM Reaction Intermediates

X-ray crystallographic characterization of enzymes at different stages in their reaction cycles can provide unique insight into the reaction pathway, the number and type of intermediates formed, and their structural context. The known mechanistic diversity in the radical S-adenosylmethionine (SAM) superfamily of enzymes makes it an appealing target for such studies as more than 100,000 sequences have been identified to date with wide-ranging reactivities that share a pattern of complex radical-mediated chemistry. Here, we review selected examples of radical SAM enzyme crystal structures representative of reactant, product, and intermediate state complexes with a particular emphasis on the strategies employed to capture these states. Broader application of structural characterization techniques to analyze mechanism and substrate specificity is certain to play an important role as more members of this family become tractable for biochemical study.

X-ray Emission Spectroscopy of Biomimetic Mn Coordination Complexes

Understanding the function of Mn ions in biological and chemical redox catalysis requires precise knowledge of their electronic structure. X-ray emission spectroscopy (XES) is an emerging technique with a growing application to biological and biomimetic systems. Here, we report an improved, cost-effective spectrometer used to analyze two biomimetic coordination compounds, [Mn^IV(OH)₂(Me₂EBC)]²⁺ and [Mn^IV(O)(OH)(Me₂EBC)]⁺, the second of which contains a key Mn^IV═O structural fragment. Despite having the same formal oxidation state (Mn^IV) and tetradentate ligands, XES spectra from these two compounds demonstrate different electronic structures. Experimental measurements and DFT calculations yield different localized spin densities for the two complexes resulting from Mn^IV-OH conversion to Mn^IV═O. The relevance of the observed spectroscopic changes is discussed for applications in analyzing complex biological systems such as photosystem II. A model of the S₃ intermediate state of photosystem II containing a Mn^IV═O fragment is compared to recent time-resolved X-ray diffraction data of the same state.

Full-length model of the human galectin-4 and insights into dynamics of inter-domain communication

Galectins are proteins involved in diverse cellular contexts due to their capacity to decipher and respond to the information encoded by β-galactoside sugars. In particular, human galectin-4, normally expressed in the healthy gastrointestinal tract, displays differential expression in cancerous tissues and is considered a potential drug target for liver and lung cancer. Galectin-4 is a tandem-repeat galectin characterized by two carbohydrate recognition domains connected by a linker-peptide. Despite their relevance to cell function and pathogenesis, structural characterization of full-length tandem-repeat galectins has remained elusive. Here, we investigate galectin-4 using X-ray crystallography, small- and wide-angle X-ray scattering, molecular modelling, molecular dynamics simulations, and differential scanning fluorimetry assays and describe for the first time a structural model for human galectin-4. Our results provide insight into the structural role of the linker-peptide and shed light on the dynamic characteristics of the mechanism of carbohydrate recognition among tandem-repeat galectins.

Simple sample processing enhances malaria rapid diagnostic test performance

Lateral flow immunochromatographic rapid diagnostic tests (RDTs) are the primary form of medical diagnostic used for malaria in underdeveloped nations. Unfortunately, many of these tests do not detect asymptomatic malaria carriers. In order for eradication of the disease to be achieved, this problem must be solved. In this study, we demonstrate enhancement in the performance of six RDT brands when a simple sample-processing step is added to the front of the diagnostic process. Greater than a 4-fold RDT signal enhancement was observed as a result of the sample processing step. This lowered the limit of detection for RDT brands to submicroscopic parasitemias. For the best performing RDTs the limits of detection were found to be as low as 3 parasites per μL. Finally, through individual donor samples, the correlations between donor source, WHO panel detection scores and RDT signal intensities were explored.

Kinetic modeling of the X-ray-induced damage to a metalloprotein

It is well-known that biological samples undergo X-ray-induced degradation. One of the fastest occurring X-ray-induced processes involves redox modifications (reduction or oxidation) of redox-active cofactors in proteins. Here we analyze room-temperature data on the photoreduction of Mn ions in the oxygen-evolving complex (OEC) of photosystem II, one of the most radiation damage-sensitive proteins and a key constituent of natural photosynthesis in plants, green algae, and cyanobacteria. Time-resolved X-ray emission spectroscopy with wavelength-dispersive detection was used to collect data on the progression of X-ray-induced damage. A kinetic model was developed to fit experimental results, and the rate constant for the reduction of OEC Mn(III) and Mn(IV) ions by solvated electrons was determined. From this model, the possible kinetics of X-ray-induced damage at a variety of experimental conditions, such as different rates of dose deposition as well as different excitation wavelengths, can be inferred. We observed a trend of increasing dosage threshold prior to the onset of X-ray-induced damage with increasing rates of dose deposition. This trend suggests that experimentation with higher rates of dose deposition is beneficial for measurements of biological samples sensitive to radiation damage, particularly at pink beam and X-ray free electron laser sources.

Fast Detection Allows Analysis of the Electronic Structure of Metalloprotein by X-ray Emission Spectroscopy at Room Temperature

The paradigm of "detection-before-destruction" was tested for a metalloprotein complex exposed at room temperature to the high x-ray flux typical of third generation synchrotron sources. Following the progression of the x-ray induced damage by Mn Kβ x-ray emission spectroscopy, we demonstrated the feasibility of collecting room temperature data on the electronic structure of native Photosystem II, a trans-membrane metalloprotein complex containing a Mn(4)Ca cluster. The determined non-damaging observation timeframe (about 100 milliseconds using continuous monochromatic beam, deposited dose 1*10(7) photons/µm(2) or 1.3*10(4) Gy, and 66 microseconds in pulsed mode using pink beam, deposited dose 4*10(7) photons/µm(2) or 4.2*10(4) Gy) is sufficient for the analysis of this protein's electron dynamics and catalytic mechanism at room temperature. Reported time frames are expected to be representative for other metalloproteins. The described instrumentation, based on the short working distance dispersive spectrometer, and experimental methodology is broadly applicable to time-resolved x-ray emission analysis at synchrotron and x-ray free-electron laser light sources.

A highly reactive mononuclear non-heme manganese(IV)-oxo complex that can activate the strong C-H bonds of alkanes

A mononuclear non-heme manganese(IV)-oxo complex has been synthesized and characterized using various spectroscopic methods. The Mn(IV)-oxo complex shows high reactivity in oxidation reactions, such as C-H bond activation, oxidations of olefins, alcohols, sulfides, and aromatic compounds, and N-dealkylation. In C-H bond activation, the Mn(IV)-oxo complex can activate C-H bonds as strong as those in cyclohexane. It is proposed that C-H bond activation by the non-heme Mn(IV)-oxo complex does not occur via an oxygen-rebound mechanism. The electrophilic character of the non-heme Mn(IV)-oxo complex is demonstrated by a large negative ρ value of -4.4 in the oxidation of para-substituted thioanisoles.

Abstract P2-09-13: 21 Gene Recurrence Scores: Racial Differences in Testing, Scores, Treatment, and Outcome

BACKGROUND: African American (AA) women experience higher breast cancer mortality than white (W) women, partly attributable to their development of poor prognosis tumors and differences in access and treatment. However mortality differences persist among estrogen receptor positive (ER+) breast cancers, despite similar stage and treatment. The 21-gene recurrence score (RS) assay (Oncotype DX) is used to determine optimal individualized treatment in patients with ER+, node negative (N-) breast cancer. Results are reported on a continuum and also trichotomized into 3 RS groups: low(0-18), intermediate(19-31) and high(>31), the latter most likely benefitting from chemotherapy, achieving less benefit with hormonal therapy, and exhibiting lower ER levels (intrinsically categorized as luminal B cancers). We investigated differences between AA and W women in RS, treatment, and outcome.

METHODS: Tumor registry data from three Atlanta hospitals identified female invasive breast cancers of AA or W descent diagnosed during 2005-2009. Additional medical record abstraction obtained information on RS, treatment, and outcome. Statistical analyses employed chi-square, fisher exact, t-tests, and multivariate logistic regression. RESULTS: Of 1987 cases (AA=1110, W=877), 773 were identified as Stage I-II, ER+N-, thus eligible for RS testing [AA=350(45.3%), W=423 (54.7%), P<0.0001]; 170 (22.2%) of those received RS testing [AA=47(13.4%), W=123(29.1%), P<0.0001]. Patients distributed into the following risk groups: Low=91, Medium=63, High=16; mean(median) RS=19.0(17.0), range=0-69.

Neither mean RS (AA=20.4, W=18.5, p=0.287) nor risk groups (Low=51.1% vs 54.5%, Medium=34.0% vs 38.2%, and High=14.9% vs 7.3% for AA and W women respectively, p=0.333) significantly differed by race. However, AA women were more likely than W women to be diagnosed under age 50 (40.4% vs 23.5%, p=0.036) with higher prevalence of tumors of larger size (Mean = 2.0 cm vs 1.6cm, p=0.038) and Grade III (23.4% vs 8.1%, p=0.0.026), and stage II disease (38.3%% vs 23.6%, p=0.057). Only grade and tumor size were associated with RS in multivariate analyses.

After median follow-up of 20 months (range 1-55), 5 women recurred (2AA, 3W); 2 low, 2 intermediate, and 1 high risk. Chemotherapy was received by 40 women (Low=7, Medium=19, High=14) and did not differ by race (AA=31.9%, W=20.3%, p=0.156). Hormonal therapy was received by 80.5% of W and 63.8% AA women (p=0.027). DISCUSSION: AA women were less likely than W women to be diagnosed with ER+N-breast cancers and to receive RS testing if diagnosed. Of those tested, RS scores did not significantly differ by race. However, AA women tended to have poorer prognostic factors. Our data suggest that testing guidelines are not equivalently applied, that selection bias in testing could be attenuating any real racial differences in RS, and that disparate outcomes could partly be explained by treatment differences, treatment effectiveness e.g. endocrine agent metabolism, compliance, as well as differences in prognostic factors; all areas requiring future exploration.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-09-13.

Metal-carbon clusters: the origin of the delayed atomic ion

Studies of the emission of electrons from excited metal-carbon cluster systems that include the Met-Car (M(8)C(12), where M is Ti, Zr, and V) also have revealed the evolution of a delayed atomic ion. The source of the delayed atomic ion, which involves the emission of ionized atoms on the microsecond time scale, is the focus of this investigation. By studying the delayed ionization of mixed zirconium and titanium carbon complexes produced in a laser vaporization source coupled to a time-of-flight mass spectrometer, for the first time both the zirconium and titanium delayed atomic ions were observed to be emitted in the same experiment. These studies allowed a determination that the source of the delayed atomic ion is an excited metal dicarbide. A plausible mechanism involving the excitation of a high Rydberg state of the metal dicarbide prior to an excited ion pair separation is proposed.

Using clinical practice analysis to improve care

BACKGROUND

Improving clinical outcomes requires that physicians examine and change their clinical practice. Sustaining outcome improvements requires a dedicated and dynamic program of analyzing and improving patient care. In 1992 North Mississippi Health Services (NMHS) implemented a program to improve physicians' clinical efficiency. CLINICAL PRACTICE ANALYSIS ( CPA): CPA uses evidenced-based guidelines and examines each physician's resource utilization, processes, and outcomes for a diagnosis or procedure. Clinical practice profiles are developed, and individual performance is compared to local and national benchmarks and presented to physicians. The CPA process is used on its own or as a component of more comprehensive performance improvements projects. Physicians have been engaged in outcome improvement by more than 55 CPA projects.

RESULTS

NHMS has progressively reduced its Medicare loss and its length of stay (LOS) to 4.9 days. Mortality and readmission rates have been reduced in specific diagnoses. The community-acquired pneumonia project reduced the LOS from 7.7 to 5.1 days, decreaesed the mortality rate from 8.9% to 5.0%, and decreased the cost of care from $4,269 to $3,834. The ischemic stroke project reduced the aspiration pneumonia rate from 6.4% to 0% and mortality from 11.0% to 4.6%. Patients' average LOS decreased from 10.7 days to 6.5 days, and their cost of care was reduced by $1,100 per patient.

DISCUSSION

Providing individualized data has engaged physicians in improving outcomes. The program has evolved from improving efficiency to managing outcomes and from simple CPA projects to integrated performance improvement projects; however, the CPA process remains the cornerstone of the current process.

Role of glutamatergic and GABAergic systems in alcoholism

The pharmacological effects of ethanol are complex and widespread without a well-defined target. Since glutamatergic and GABAergic innervation are both dense and diffuse and account for more than 80% of the neuronal circuitry in the human brain, alterations in glutamatergic and GABAergic function could affect the function of all neurotransmitter systems. Here, we review recent progress in glutamatergic and GABAergic systems with a special focus on their roles in alcohol dependence and alcohol withdrawal-induced seizures. In particular, NMDA-receptors appear to play a central role in alcohol dependence and alcohol-induced neurological disorders. Hence, NMDA receptor antagonists may have multiple functions in treating alcoholism and other addictions and they may become important therapeutics for numerous disorders including epilepsy, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's chorea, anxiety, neurotoxicity, ischemic stroke, and chronic pain. One of the new family of NMDA receptor antagonists, such as DETC-MESO, which regulate the redox site of NMDA receptors, may prove to be the drug of choice for treating alcoholism as well as many neurological diseases.

Association of L-glutamic acid decarboxylase to the 70-kDa heat shock protein as a potential anchoring mechanism to synaptic vesicles

Recently we have reported that the membrane-associated form of the gamma-aminobutyric acid-synthesizing enzyme, l-glutamate decarboxylase (MGAD), is regulated by the vesicular proton gradient (Hsu, C. C., Thomas, C., Chen, W., Davis, K. M., Foos, T., Chen, J. L., Wu, E., Floor, E., Schloss, J. V., and Wu, J. Y. (1999) J. Biol. Chem. 274, 24366-24371). In this report, several lines of evidence are presented to indicate that l-glutamate decarboxylase (GAD) can become membrane-associated to synaptic vesicles first through complex formation with the heat shock protein 70 family, specifically heat shock cognate 70 (HSC70), followed by interaction with cysteine string protein (CSP), an integral protein of the synaptic vesicle. The first line of evidence comes from purification of MGAD in which HSC70, as identified from amino acid sequencing, co-purified with GAD. Second, in reconstitution studies, HSC70 was found to form complex with GAD(65) as shown by gel mobility shift in non-denaturing gradient gel electrophoresis. Third, in immunoprecipitation studies, again, HSC70 was co-immunoprecipitated with GAD by a GAD(65)-specific monoclonal antibody. Fourth, HSC70 and CSP were co-purified with GAD by specific anti-GAD immunoaffinity columns. Furthermore, studies here suggest that both GAD(65) and GAD(67) are associated with synaptic vesicles along with HSC70 and CSP. Based on these findings, a model is proposed to link anchorage of MGAD to synaptic vesicles in relation to its role in gamma-aminobutyric acid neurotransmission.

Effects of hospitalists on cost, outcomes, and patient satisfaction in a rural health system

PURPOSE

Previous studies have examined the effects of hospitalists in urban academic hospitals. We compared the outcomes of patients treated by hospitalists with those of patients treated by internists at a 647-bed rural community hospital.

SUBJECTS AND METHODS

The 443 patients in the hospitalists' 10 most common diagnosis-related groups (DRGs) were compared with 1,681 patients in the same DRGs who were cared for by internists in fiscal year 1998. Length of stay, cost of care, patient illness severity, patient satisfaction, 30-day readmission rate, inpatient mortality, discharge status, and resource utilization were compared.

RESULTS

The hospitalists' patients had a shorter mean (+/- SD) length of stay (4.1 +/- 3.0 days versus 5.5 +/- 4.9 days, P <0.001) and their cost of care was less than that of the internists' patients ($4,098 +/- $2,455 versus $4,658 +/- $4,084, P <0.001). Analyses that adjusted for patient age, race, sex, insurance status, severity of illness, and specific medical comorbidities confirmed these differences. The differences between hospitalists and internists were most apparent among very ill patients. Mortality rates were similar (4.5% for hospitalists versus 4.9% for internists, P = 0.80), as were the readmission rates (4.5% for hospitalists versus 5.6% for internists, P = 0.41). Patient satisfaction was similar for both groups. The internists used more resources in 8 of 11 categories.

CONCLUSIONS

The hospitalists provided cost-effective care, particularly for the sickest patients, with good outcomes and patient satisfaction.

A novel method for expression and large-scale production of human brain l-glutamate decarboxylase

l-Glutamate decarboxylase (GAD; EC 4.1.1.15) is the rate-limiting enzyme involved in the synthesis of gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the mammalian brain. Imbalance in the conversion of glutamate to GABA has been implicated in a host of human diseases. Studies on the structure, function, and therapeutic use of GAD have been precluded by insufficient quantities of purified active enzyme. Here we report a novel methodology for the expression and large-scale production of enzymatically active, pure, recombinant human GAD65 and GAD67. This method circumvents the sequestering of expressed protein into insoluble inclusion bodies and reduces production of truncated proteins. The availability of sufficient quantities of purified HGAD65 and HGAD67 has allowed for the production of specific polyclonal antibodies that discriminate between the two isoforms. This methodology, in addition to providing key human brain enzymes, may be generally applicable to other systems.

Role of synaptic vesicle proton gradient and protein phosphorylation on ATP-mediated activation of membrane-associated brain glutamate decarboxylase

Previously, we have shown that the soluble form of brain glutamic acid decarboxylase (GAD) is inhibited by ATP through protein phosphorylation and is activated by calcineurin-mediated protein dephosphorylation (Bao, J., Cheung, W. Y., and Wu, J. Y. (1995) J. Biol. Chem. 270, 6464-6467). Here we report that the membrane-associated form of GAD (MGAD) is greatly activated by ATP, whereas adenosine 5'-[beta,gamma-imido]triphosphate (AMP-PNP), a non-hydrolyzable ATP analog, has no effect on MGAD activity. ATP activation of MGAD is abolished by conditions that disrupt the proton gradient of synaptic vesicles, e.g. the presence of vesicular proton pump inhibitor, bafilomycin A1, the protonophore carbonyl cyanide m-chorophenylhydrazone or the ionophore gramicidin, indicating that the synaptic vesicle proton gradient is essential in ATP activation of MGAD. Furthermore, direct incorporation of (32)P from [gamma-(32)P]ATP into MGAD has been demonstrated. In addition, MGAD (presumably GAD65, since it is recognized by specific monoclonal antibody, GAD6, as well as specific anti-GAD65) has been reported to be associated with synaptic vesicles. Based on these results, a model linking gamma-aminobutyric acid (GABA) synthesis by MGAD to GABA packaging into synaptic vesicles by proton gradient-mediated GABA transport is presented. Activation of MGAD by phosphorylation appears to be mediated by a vesicular protein kinase that is controlled by the vesicular proton gradient.

Atrial natriuretic peptide and the development of congestive heart failure in the oldest old: a seven-year prospective study

BACKGROUND

Atrial natriuretic peptide (ANP) levels are elevated in symptomatic heart failure and correlate with invasively measured left heart pressures.

OBJECTIVE

To examine the association between plasma ANP level and the subsequent development of congestive heart failure (CHF) in older subjects with no history of CHF.

DESIGN

A 7-year, prospective, blinded, cohort study.

SETTING

A life care facility in Boston, Massachusetts.

PARTICIPANTS

Two hundred fifty-six frail older subjects (mean age 88 +/- 7) with no history of CHF at study entry.

MAIN OUTCOME MEASURE

Clinical episodes of CHF with confirmatory chest roentgenogram findings. Cox proportional hazard analyses were performed to examine the relationship between ANP levels and the development of CHF while controlling for 19 clinical, physical, and laboratory parameters. A Kaplan-Meier estimator (log-rank test) was used to determine if the development of CHF differed by tertile of ANP.

RESULTS

During the follow-up period, 32% of the cohort developed CHF. The mean ANP level in the CHF group was 95 pmol/L +/- 11 pmol/L versus 60 pmol/L +/- 5 pmol/L in the no CHF group (two tailed t test P = .005). On multivariate analysis, a high ANP level was found to be associated significantly (P = .01) with the development of CHF.

CONCLUSIONS

There is a statistically significant association between ANP level and the subsequent development of CHF in frail older individuals with no history of CHF.

Change of bone mass in postmenopausal Caucasian women with and without hormone replacement therapy is associated with vitamin D receptor and estrogen receptor genotypes

Our purpose is to assess whether genotypes of the vitamin D receptor (VDR) and estrogen receptor (ER) and their interaction influence changes in bone mass in postmenopausal Caucasian women with and without hormone replacement therapy (HRT). A population of 108 US Mid-West women who participated in a study of low-dose continuous estrogen/progestin was genotyped at the VDR BsmI site and the ER XbaI and PvuII sites. Adequate vitamin D and calcium nutritional intakes were assured in all the study subjects. For the 3.5-year duration of the study, we analyzed changes in bone mineral density (BMD) at the spine, femoral neck, distal radius, and the total body (total body bone mineral content, tbBMC). We adjusted for confounding factors, such as age and weight, in the analysis. We found that VDR and/or ER genotypes and/or their interaction generally had significant effects on the changes in the bone mass measurements in both the placebo and HRT groups. When a significant gene-by-gene interaction exists between VDR and ER genotypes, failure to account for them in analyses may yield nonsignificant results, even if significant genotypic effects exist. The amount of variation in changes in bone mass measurements explained by the total genotypic effects of the VDR and ER loci varies from approximately 1.0% (for the tbBMC changes in combined placebo and HRT groups) to approximately 18.7% (for the spine BMD changes in the HRT group). These results suggest that individual genotypes are important factors in determining changes in bone mass in the elderly with and without HRT and thus may need to be considered with respect to the treatment to preserve bone mass in elderly Caucasian women.

Clinical efficiency tools improve stroke management in a rural southern health system

BACKGROUND AND PURPOSE

Ischemic stroke is a high-volume and financially draining diagnosis at this rural health system. The purpose of this clinical practice analysis was to identify resource utilization and clinical process inefficiencies and to promote clinically efficient, evidence-based improvements.

METHODS

A retrospective analysis of medical record and financial databases of 356 patients with ischemic stroke was performed. The medical record data were adjusted for severity, and outliers were eliminated. The resources utilized by each physician were determined. Comparative graphs were prepared, presented, and discussed. The physicians implemented two types of changes: (1) alteration of resource utilization and consultation patterns and (2) support of clinical process improvement. In 1997, a follow-up analysis of 399 patients was performed.

RESULTS

The initial comparison of internists' to neurologists' patient populations found the following: patient age (75 versus 65 years), patient severity ratings (2.8 versus 2.5), length of stay (10.7 versus 8.8 days), costs ($7360 versus $6862), mortality rates (12.5% versus 8.9%), and aspiration pneumonia rate (8.5% versus 3.8%). A comparison of the 1995 analysis to the 1997 analysis revealed the following per patient resource utilization decreases (all P < 0.05): chemistry laboratory, 2.65 to 1.95 studies; intravenous fluids, 2.85 to 1.85 L; oxygen use, 6.06 to 2.75 U; and nifedipine use, 1.62 to 0.33 capsules. The clinical process improvements resulted in the following overall outcomes (all P < 0.05 except mortality): length of stay (7.2 days), nonadjusted costs ($6246), mortality (6.5%), and rates of pneumonia (2.7%).

CONCLUSIONS

Objective analysis of resource utilization resulted in physicians changing their individual management of stroke and collectively supporting clinical process changes that improved clinical and financial outcomes.

Pharmacologic management of depression in the elderly

Depression, the most common geriatric psychiatric disorder, is a disabling mood disorder that impairs one's well-being and may even threaten a sufferer's life. Severely depressed elderly persons are more likely to kill themselves than individuals in any other age group. However, geriatric depression is, for the most part, a treatable and manageable illness. Antidepressant medication can be very effective in treating major depressive disorder (MDD). Because age-related physical changes in the elderly produce pharmacokinetics that are often different than that experienced by younger adults, different doses are often necessary. This article summarizes recommendations for selecting and initiating appropriate antidepressant therapy in elderly persons suffering from MDD. The benefits and drawbacks of tricyclic antidepressant agents, and other atypical antidepressant agents are discussed. Phases of treatment, drug selection, dosing, and educational tips for pharmacotherapy are presented.

Clinical applications of computer-based health information

Competitive health care systems are improving their clinical and cost efficiency by performing clinical practice analyses. Large numbers of severity-adjusted cases provide the most objective data for making clinical efficiency decisions. The most cost-effective way to perform these analyses is to utilize well-coded, computer-based health information. This requires consistent coding of patients' comorbidities and complications as well as an interactive working relationship between coders and clinicians providing the clinical practice analysis. The article describes one hospital's evolving clinical efficiency information needs, how its health information system met them, the clinical practice analysis procedure, and the outcomes of this clinical practice analysis.