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Park S, Liao X, Johnson ME, Fung LW. 1H, 15N, and 13C NMR backbone assignments of the N-terminal region of human erythrocyte alpha spectrin including one structural domain. JOURNAL OF BIOMOLECULAR NMR 1999; 15:345-346. [PMID: 10685345 DOI: 10.1023/a:1008339507922] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Ostrowski ML, Johnson ME, Truong LD, Hicks MJ, Smith FE, Spjut HJ. Malignant chondroblastoma presenting as a recurrent pelvic tumor with DNA aneuploidy and p53 mutation as supportive evidence of malignancy. Skeletal Radiol 1999; 28:644-50. [PMID: 10591928 DOI: 10.1007/s002560050567] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We report a rare case of malignant chondroblastoma, which presented in a 47-year-old man as a recurrent tumor, 18 years following wide excision of a typical pelvic chondroblastoma. Radiologic studies of the recurrent tumor showed a large, lytic, destructive lesion of the right pelvic bones and femur, with a pathologic fracture of the latter, a large pelvic soft tissue mass, and multiple pulmonary metastases. Biopsy tissue showed typical features of chondroblastoma, but also increased nuclear atypia, hyperchromasia, and pleomorphism, compared to the original tumor, and, most significantly, abnormal mitotic figures. Immunohistochemical studies of the recurrent tumor revealed p53 mutation and extensive proliferative activity, and flow cytometric studies showed DNA aneuploidy, none of which was present in the original tumor. The patient received chemotherapy and radiation, but died of disease eight months after presentation. We also review chondroblastoma in general, to assign this unusual lesion to a tumor subtype.
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Hughes RE, Johnson ME, O'Driscoll SW, An KN. Normative values of agonist-antagonist shoulder strength ratios of adults aged 20 to 78 years. Arch Phys Med Rehabil 1999; 80:1324-6. [PMID: 10527095 DOI: 10.1016/s0003-9993(99)90037-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To determine normative values for isometric flexion/extension, abduction/adduction, and external/internal rotation strength ratios about the shoulder and to determine if these ratios are affected by age or gender. STUDY DESIGN A cross-sectional study of 120 healthy volunteers (60 men, 60 women) aged 20 to 78 years. SETTING Orthopedic research laboratory. METHODS Flexion and extension strengths were measured isometrically using a Cybex II dynamometer at arm flexion angles of 30 degrees, 60 degrees, and 90 degrees. Abduction and adduction strengths were measured at 30 degrees, 60 degrees, and 90 degrees abduction. Internal and external rotation strengths were measured (1) with the arm abducted 15 degrees and neutral external/internal rotation and (2) with the arm abducted 90 degrees and externally rotated 30 degrees above the transverse plane. OUTCOME MEASURES Isometric strength ratios for flexion/extension, abduction/adduction, and external/internal rotation. RESULTS No statistically significant differences in agonist/antagonist strength ratios were found between dominant and nondominant sides or between genders. Age was associated with changes in strength ratios for measurements taken with the arm flexed or abducted 90 degrees. Posture was found to affect strength ratios. CONCLUSIONS These data can serve as a normative reference for clinical use.
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Bastyr EJ, Johnson ME, Trautmann ME, Anderson JH, Vignati L. Insulin lispro in the treatment of patients with type 2 diabetes mellitus after oral agent failure. Clin Ther 1999; 21:1703-14. [PMID: 10566566 DOI: 10.1016/s0149-2918(99)80049-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This study assessed the safety profile and efficacy of a new combination therapy (insulin lispro plus sulfonylurea) in patients with type 2 diabetes mellitus experiencing secondary oral agent failure. A total of 423 patients were randomly assigned to 3 treatment groups: preprandial insulin lispro plus sulfonylurea (L + S), bedtime neutral protamine Hagedorn (NPH) insulin plus sulfonylurea (N + S), and preprandial insulin lispro plus bedtime NPH insulin (L + N). Mean decreases in glycosylated hemoglobin from baseline were 1.60%+/-1.27% for patients receiving L + S, 1.21%+/-1.21% for those receiving N + S, and 1.40%+/-1.46% for those receiving L + N (within treatment, P<0.001; for L + S vs. N + S, P = 0.003). Fasting blood glucose level was higher in patients receiving L + S (171+/-46.5 mg/dL) or L + N (166+/-52.5 mg/dL) than in those receiving N + S (144+/-48.2 mg/dL) (P<0.001, for both comparisons). Conversely, postprandial blood glucose level was lower in patients receiving L + S (165+/-41.6 mg/dL) or L + N (165+/-46.3 mg/dL) than in those receiving N + S (213+/-58.3 mg/dL) (P<0.001, for both comparisons). The overall rate of hypoglycemia (episodes per 30 days) was not statistically significant when the L + S, N + S, and L + N therapies were compared (0.99+/-1.74 vs. 0.87+/-2.31 vs. 1.16+/-2.38, respectively). The rate of nocturnal hypoglycemia was lowest in the L + S group (0.00+/-0.00 vs. 0.10+/-0.37 for the N + S group vs. 0.15+/-0.54 for the L + N group; P = 0.004). L + S, which has a safety profile equal to those of N + S and L + N, is an effective treatment for patients with type 2 diabetes who experience oral sulfonylurea agent failure. L + S offers an alternative to these established combination therapies in patients whose type 2 diabetes cannot be controlled with a sulfonylurea alone.
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Markham PN, Westhaus E, Klyachko K, Johnson ME, Neyfakh AA. Multiple novel inhibitors of the NorA multidrug transporter of Staphylococcus aureus. Antimicrob Agents Chemother 1999; 43:2404-8. [PMID: 10508015 PMCID: PMC89491 DOI: 10.1128/aac.43.10.2404] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The multidrug transporter NorA contributes to the resistance of Staphylococcus aureus to fluoroquinolone antibiotics by promoting their active extrusion from the cell. Previous studies with the alkaloid reserpine, the first identified inhibitor of NorA, indicate that the combination of a chemical NorA inhibitor with a fluoroquinolone could improve the efficacy of this class of antibiotics. Since reserpine is toxic to humans at the concentrations required to inhibit NorA, we sought to identify new inhibitors of NorA that may be used in a clinical setting. Screening of a chemical library yielded a number of structurally diverse inhibitors of NorA that were more potent than reserpine. The new inhibitors act in a synergistic manner with the most widely used fluoroquinolone, ciprofloxacin, by substantially increasing its activity against both NorA-overexpressing and wild-type S. aureus isolates. Furthermore, the inhibitors dramatically suppress the emergence of ciprofloxacin-resistant S. aureus upon in vitro selection with this drug. Some of these new inhibitors, or their derivatives, may prove useful for augmentation of the antibacterial activities of fluoroquinolones in the clinical setting.
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Abstract
Normative data are useful for assessing isometric shoulder strength in patients with bilateral shoulder abnormalities. The purpose of this study was to develop a normative database for shoulder strength in the clinically relevant positions and movements. Twenty combinations of exertions and postures-including flexion, extension, abduction, adduction, internal rotation, and external rotation-were tested for both the dominant and nondominant sides. Strength was measured isometrically using a modified Cybex II dynamometer. The cross-sectional study design included 120 subjects (60 women and 60 men) ranging in age from 20 to 78 years from southern Minnesota. Tables of normative strength data were constructed. Multivariate analyses were performed to assess the effect of age, sex, and weight on strength. Age was negatively associated with all strength measures, and weight was positively associated with them. Men were stronger than women when controlling for age and weight. Statistically significant differences between dominant and nondominant shoulders were found for only some of the strength measures taken. These normal data will be useful to the clinician, as they permit a standard against which to compare shoulder strength.
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Mitragotri S, Johnson ME, Blankschtein D, Langer R. An analysis of the size selectivity of solute partitioning, diffusion, and permeation across lipid bilayers. Biophys J 1999; 77:1268-83. [PMID: 10465741 PMCID: PMC1300418 DOI: 10.1016/s0006-3495(99)76978-x] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The lipid bilayers of cell membranes are primarily responsible for the low passive transport of nonelectrolytes across cell membranes, and for the pronounced size selectivity of such transport. The size selectivity of bilayer permeation has been hypothesized to originate from the hindered transport of solutes across the ordered-chain region. In this paper, we develop a theoretical description that provides analytical relationships between the permeation properties of the ordered-chain region of the lipid bilayer (partition and diffusion coefficients) and its structural properties, namely, lipid chain density, free area, and order parameter. Emphasis is placed on calculating the size selectivity of solute partitioning, diffusion, and overall permeability across the ordered-chain region of the lipid bilayer. The size selectivity of solute partitioning is evaluated using scaled-particle theory, which calculates the reversible work required to create a cavity to incorporate a spherical solute into the ordered-chain region of the lipid bilayer. Scaled-particle theory is also used to calculate the work required to create a diffusion path for solutes in the interfacial region of the lipid bilayer. The predicted size dependence of the bilayer permeability is comparable to that observed experimentally. The dependence of solute partition and diffusion coefficients on the bilayer structural parameters is also discussed.
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Gee AJ, Groen LA, Johnson ME. Determination of fatty acid amides as trimethylsilyl derivatives by gas chromatography with mass spectrometric detection. J Chromatogr A 1999; 849:541-52. [PMID: 10457449 DOI: 10.1016/s0021-9673(99)00609-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Fatty acid amides are a newly emerging class of compounds with biological activity. The amides are formed enzymatically in vivo. Analysis of fatty acid amides has been accomplished by gas chromatography coupled with mass spectrometry. Fatty acid amides required derivatization prior to analysis at high temperatures due to thermal instability. Trimethylsilylation of fatty acid amides has been accomplished under optimum reaction conditions. The limit of detection for the silylated amides is approximately 1 pmol, with the lowest detected level being 700 fmol for the lauramide derivative. Quantitation of fatty acid amide derivatives can be accomplished by monitoring m/z 59 or m/z M-71, the only two major fragments formed in the ion trap mass spectrometer with electron impact ionization. The smaller fragment is the result of a newly reported, McLafferty-type rearrangement; M-71 resulted from loss of an n-pentyl fragment. Either peak gave four-five orders of magnitude linear dynamic range. Numerous trimethylsilylamides from C7 to C20 were separated under standard conditions. Elution was linear with the number of carbons and was systematically affected by the number and position of the double bonds.
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Li M, Lin Z, Johnson ME. Structure-based design and synthesis of novel thrombin inhibitors based on phosphinic peptide mimetics. Bioorg Med Chem Lett 1999; 9:1957-62. [PMID: 10450962 DOI: 10.1016/s0960-894x(99)00319-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Based on the structure of the thrombin--NAPAP complex, phosphinic dipeptide mimetics were designed as novel thrombin inhibitors. Synthesis and evaluation of these inhibitors revealed a promising lead with an IC50 of 0.6 microM.
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Zhou Y, Johnson ME. Comparative molecular modeling analysis of-5-amidinoindole and benzamidine binding to thrombin and trypsin: specific H-bond formation contributes to high 5-amidinoindole potency and selectivity for thrombin and factor Xa. J Mol Recognit 1999; 12:235-41. [PMID: 10440994 DOI: 10.1002/(sici)1099-1352(199907/08)12:4<235::aid-jmr460>3.0.co;2-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The coagulation cascade enzymes thrombin and factor Xa are known to have specificity pockets very similar to those of trypsin and plasmin. However, comparative molecular modeling analysis of the crystal structures of benzamidine-thrombin and benzamidine-trypsin, in conjunction with a docking analysis of 5-amidinoindole and related inhibitors in both enzymes reveals subtle differences between the specificity sites of the two types of enzymes. Specifically, thrombin and factor Xa, which have an alanine residue at position 190, exhibit increased activities for the rigid and more bulky bicyclic derivatives of benzamidine (e.g. amidinobenzofuran, amidinothiophene and amidinoindole), because of additional hydrophobic and H-bond interactions between the inhibitors and the specificity sites, whereas enzymes with a serine residue at position 190, like trypsin and plasmin, exhibit little difference in activity among the same set of compounds because of the orientational restriction imposed on the inhibitors by Ser190, which forms an additional H-bond with the amidino group of the inhibitors. Enzymes of both groups show similar responses to the flexible aminobenzamidine since the smaller size and the rotatable anilino group of the inhibitor would allow the inhibitor to achieve favorable electrostatic interactions with both groups of enzymes. 5-amidinoindole is the most dramatic example of the rigid bicyclic type inhibitor. Based on our docking analysis, we propose that a selective H-bond with the hydroxyl group of the catalytic Ser195 and the subtle differences in steric fit imposed by Ala/Ser at position 190 explain the high potency and selectivity of 5-amidinoindole for thrombin and factor Xa.
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Johnson ME, Hauck C. Beliefs and opinions about hypnosis held by the general public: a systematic evaluation. AMERICAN JOURNAL OF CLINICAL HYPNOSIS 1999; 42:10-20. [PMID: 10570849 DOI: 10.1080/00029157.1999.10404241] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A study was conducted to systematically evaluate the general public's beliefs and opinions about hypnosis as well as to ascertain the sources of their beliefs. The evaluation was based on four samples representing different ages, socio-economic backgrounds, interests, and geographical locations. A 27 item, two-page questionnaire was developed to evaluate the opinions on a wide variety of topics related to hypnosis and clinical applications of hypnosis. The results indicate that although the different sample groups obtain their information about hypnosis from different sources, their beliefs about hypnosis are remarkably consistent. While the results indicate an interesting mix of ideas about hypnosis, some results indicate that most people have a positive view of the therapeutic benefits, with a vast majority of respondents believing that it reduces the time that is usually required to uncover causes of a person's problems and that hypnotized persons can undergo dental and medical procedures without pain. Other findings indicate that an extremely large proportion of the general public views hypnosis as a powerful tool to recover accurate memories under a variety of conditions including accurate memories as far back as birth or even past lives. These findings may extend and dovetail with the findings that some professionals overestimate the influence of hypnosis on retrieving accurate memories.
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Turner SJ, Paschane DM, Johnson ME, Fisher DG, Fenaughty AM. Alcohol consumption among Alaskan drug users. Int J Circumpolar Health 1999; 57 Suppl 1:447-53. [PMID: 10093323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
This study investigated predictors of alcohol consumption among drug users not currently in treatment in Anchorage, Alaska. Data were collected from 114 female and 269 male drug users via structured interviews. Alcohol consumption was defined as estimated number of drinks consumed in the last 30 days. Results revealed a high proportion consuming alcohol within the last 48 hours and 30 days (73% and 96%, respectively). Stepwise multiple regression revealed that five variables, accounting for 9% of the variance, were significantly related to alcohol consumption. Positively related were greater perceived risk of getting AIDS; obtaining income from spouse, family, or friend; living on the streets or in a shelter; or living in a hotel or boarding house. Negatively related was having an education level greater than high school. For those participants who reported having sex during the last 30 days, two variables were positively related to alcohol consumption and accounted for 17% of the variance: number of times used alcohol with sex and frequency of sex without a condom. In addition to identifying several demographic variables that are significantly related to alcohol consumption, the results document the relationship between alcohol consumption and unsafe sexual practices.
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Johnson ME, Brems C, Fisher DG. Unmet treatment needs of drug users in Alaska: correlates and societal costs. Int J Circumpolar Health 1999; 57 Suppl 1:467-73. [PMID: 10093326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
This study assessed the unmet treatment needs of drug users in Anchorage, Alaska. It revealed that almost half of the drug users who desire treatment cannot secure it, largely for external reasons. The primary barrier to treatment was lack of availability of treatment slots, followed by excessive treatment costs and restrictive admission criteria. Unlike other studies, this investigation did not suggest that members of ethnic minority groups, women, and parenting women were disproportionately disadvantaged with regard to ability to secure treatment. However, substance abusers who also met criteria for a co-morbid psychiatric diagnosis other than substance abuse or dependence had more difficulty than their non-co-morbid peers in finding available treatment slots. Social, legal, and medical costs incurred by unsuccessful treatment seekers are outlined and suggest significant cost, as well as perpetuation of intergenerational cycles of violence and substance use.
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Abstract
There have been few studies that have attempted to understand the world of one who is mentally ill. This interpretive phenomenological study, which began as a study of the meaning of being restrained, became a glimpse into mental illness. For this study, 10 psychiatric patients were questioned in unstructured interviews. The taped interviews were transcribed, and the resulting texts were analyzed with use of a modification of an eight-stage process. Heideggerian hermeneutical phenomenology provided the philosophical framework for this study. Two major themes--struggling and "why me?"--revealed what it is like for the participants to live with a serious mental illness. These participants struggled with the staff on the unit, with being restrained, and with the symptoms of their illness. As part of their struggling, they asked, "Why me?"--a question that could be interpreted existentially as, why are things the way they are and not some other way? Finally, this study underscores how important it is for the nurse caring for a psychiatric patient to enter into, and try to understand, the world of patients with mental illnesses.
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Abstract
OBJECTIVES Clinical case studies have implicated depression as a possible side-effect of interferon treatment for the Hepatitis C virus (HCV). However, because these studies generally did not include a pretreatment assessment of depression, it cannot be definitively stated whether depression is a side-effect of interferon treatment, a syndrome coexisting with HCV, or a common characteristic of individuals who are vulnerable to HCV infection. To gather more information about this issue, self-reported depressive symptomatology of drug users with HCV who have not received interferon treatment was compared to that of uninfected drug users. METHODS Subjects were 309 drug users not currently in substance abuse treatment who were participating in a National Institute on Drug Abuse project. Subjects completed the Center for Epidemiological Studies-Depression (CES-D) instrument and provided a blood sample for HCV testing. RESULTS Serological findings revealed that 52.4% of the subjects tested positive for HCV antibodies. Of the HCV-positive subjects, 57.2% had significant depressive symptomatology, whereas only 48.2% of the HCV-negative subjects did, for an overall rate of 52.6%. The two groups also differed on two specific dimensions of depression, with the HCV-positive group scoring lower on the Positive Affect scale and higher on the Somatic/Retarded Activity scale. CONCLUSIONS These findings reveal high levels of depressive symptomatology among drug users, as well as the possibility of a coexisting depressive syndrome with HCV infection. These findings raise the possibility that depression associated with interferon treatment may, at least partially, be accounted for by preexisting depression. Further research is needed to determine the nature and origins of depression in individuals in treatment with interferon for HCV with specific focus placed on determining the dimensions of depression associated with HCV infection and interferon treatment.
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Abstract
Previous research about the use of restraints has mainly sought generalizations regarding (a) who is likely to be restrained, (b) the frequency of the use of restraints, and (c) the behavior that precipitates the application of restraining devices. Therefore, there has been a paucity of research that attempts to understand the impact of restraint on the restrained person. The purpose of this study was to understand the meaning of the experience of being restrained for 10 psychiatric patients who had been restrained in leather restraints. Participants were interviewed in unstructured interviews. The taped interviews were transcribed and analyzed by means of a modification of an eight-stage interpretive process, grounded in Heideggerian phenomenology. In this article the theme of power is reported and discussed.
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Davis JL, Growney ES, Johnson ME, Iuliano BA, An KN. Three-dimensional kinematics of the shoulder complex during wheelchair propulsion: a technical report. JOURNAL OF REHABILITATION RESEARCH AND DEVELOPMENT 1998; 35:61-72. [PMID: 9505254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Methods for the three-dimensional (3-D) kinematic analysis of the shoulder complex (humerus relative to trunk) are presented and their use demonstrated in this analysis of shoulder motion during wheelchair propulsion. Ten subjects propelled two different wheelchairs (adjustable and conventional chairs) while the motions of the left arm and trunk were measured using a video tracking system. Eulerian angles described the sequence-dependent rotations of the humerus relative to the trunk. Wheel angular velocity and acceleration, hand position on the handrim, and duration of cycle subphases were also measured. Selected temporal and kinematic parameters were derived from the time-normalized average cycle of each subject on each wheelchair. Within-subject variation of these parameters according to wheelchair type were compared using a two-tailed t-test for paired observations. The adjustable chair made available a larger propulsion are compared with the conventional chair. Only the minimum amount of elevation demonstrated a significant difference between chairs (the conventional chair had a smaller minimum than the adjustable chair) at the corrected significance level of p < 0.001. Other differences, though not statistically significant, were still informative. Less shoulder internal rotation but more overall shoulder motion was observed during recovery phase in the adjustable chair as compared with the conventional chair. The methods presented for measuring the 3-D kinematics of the shoulder complex during wheelchair propulsion proved feasible for future use in studies that will address shoulder kinetics, energy requirements, wheelchair design, and chronic use disorders.
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Johnson ME, Blankschtein D, Langer R. Evaluation of solute permeation through the stratum corneum: lateral bilayer diffusion as the primary transport mechanism. J Pharm Sci 1997; 86:1162-72. [PMID: 9344175 DOI: 10.1021/js960198e] [Citation(s) in RCA: 203] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Solute permeation across human stratum corneum (SC) was examined in terms of the fundamental bilayer transport properties. A mathematical model was developed to describe the macroscopic SC permeation via the interkeratinocyte lipid domain in terms of (i) the structure and dimensions of the SC, and (ii) the microscale lipid bilayer transport properties, which include the bilayer/water partition coefficient, the lateral diffusion coefficient, the interfacial transbilayer mass transfer coefficient, and the intramembrane transbilayer mass transfer coefficient. The relative importance of the diffusive resistances associated with the bilayer transport properties was evaluated with the model and experimental data. Lateral diffusion coefficients in SC lipid bilayers were calculated from 120 human skin permeability measurements, and compared with previously reported measurements made in SC-extracted lipids. Good qualitative and quantitative agreement was observed, indicating that, in the context of the model, the diffusive resistance associated with lateral diffusion is sufficient to explain the overall resistance of solute permeation through the SC. A similar analysis shows that the diffusive resistance associated with interfacial transbilayer transport is not capable of explaining the experimental permeation values, thus supporting this finding. The lateral diffusion analysis also revealed a bifunctional size dependence of transport within the SC, with a strong size dependence for small solutes (<300 Da) and a weak size dependence for larger solutes.
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Yu B, Kienbacher T, Growney ES, Johnson ME, An KN. Reproducibility of the kinematics and kinetics of the lower extremity during normal stair-climbing. J Orthop Res 1997; 15:348-52. [PMID: 9246080 DOI: 10.1002/jor.1100150306] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The purpose of this study was to examine the intrasubject reproducibility of the kinematic and kinetic measures of the lower extremity during normal stair-climbing. Three-dimensional video and force-plate data were collected for three trials per subject during each of three conditions: ascending, descending, and level walking. Three-dimensional angles and moments of the ankle, knee, and hip joints were calculated. The coefficient of multiple correlation was used to determine the intrasubject reproducibility of joint angles and resultant moments. Analysis of variance with repeated measures was conducted to compare the magnitudes of the coefficients between different steps, different joints, and different joint functions. The results showed that (a) generally, the kinematic and kinetic measures of normal subjects climbing stairs were reproducible; (b) the kinetic measures during the transition steps from level walking to ascending and from descending to level walking were significantly less reproducible than those during the other steps; (c) the data from the sagittal plane were more reproducible than those from the other two planes; and (d) the kinetic measures were more reproducible than the kinematic measures, especially for abduction-adduction and internal-external rotation.
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Damron TA, Rock MG, O'Connor MI, Johnson ME, An KN, Pritchard DJ, Sim FH, Shives TC. Distal upper extremity function following proximal humeral resection and reconstruction for tumors: contralateral comparison. Ann Surg Oncol 1997; 4:237-46. [PMID: 9142385 DOI: 10.1007/bf02306616] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Most functional analyses after limb salvage operations about the shoulder have focused on proximal function with the assumption that distal function is largely unaffected. This analysis examines distal function objectively. METHODS Objective laboratory data regarding distal upper extremity strength after reconstructive procedures for tumors near the shoulder joint was collected over a 16-year period. Thirty-two patients were able to participate fully in the data collection at an average most recent follow-up duration of > 3.5 years. RESULTS Statistically significant reductions on the involved side compared with the uninvolved side in grip, forearm pronation, forearm supination, elbow flexion, and elbow extension strength were documented (p < 0.05). The magnitude of reduction in strength diminishes distally, with the greatest effect in this group of patients being observed in elbow extension, followed by elbow flexion, forearm supination, and forearm pronation. Grip strength consistently showed the least amount of strength reduction compared with the uninvolved side, even within resection and reconstruction groups. Subjective patient rating of dexterity was no less than 3 of 5. Ninety percent of patients rated their dexterity 4 of 5 (52%) or 5 of 5 (38%). CONCLUSIONS Despite the insistence of "normal" function in the distal upper extremity after limb salvage procedures, complete normality is not maintained. However, the degree of maintenance of distal function appears to be high, especially for grip strength and forearm pronation strength, and patient satisfaction is acceptable.
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Samarasinghe SD, Balasubramaniam A, Johnson ME. Proton Nuclear Magnetic Resonance Studies of the Structure of Neuropeptide V and its Analogs. Curr Med Chem 1997. [DOI: 10.2174/0929867304666220309205812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
NPY is regarded as the most common peptide in the central and peripheral nervous systems and heart of many mammalian species including man. It has been found to perform critical regulatory functions in behavior, control of the cardiovascular system, memory processing etc. Development of highly selective and potent antagonists will allow better understanding of the pathological and physiological roles of NPY. In the process of designing potent receptor antagonists, which are essential in detailed studies of structure function relationships, NMR has played a major role in determining the solution structure of NPY and its analogs. Sequential proton NMR assignments have been made using several two dimensional techniques, COSY, DQFCOSY, HOHAHA, NOESY and ROESY. NMR has served as a complementary technique to X-ray since solid state studies do not necessarily always provide the correct picture of molecular conformation in solution, particularly for small flexible peptides. NPY consists of an a-helix domain (residues 15-35) with a hinge at position 27 and a polyproline stretch (residues 1--10) connected by a tight hairpin (residues 11-14). NMR has provided critical information in demonstrating formation of NPY dimers in aqueous media. Based on these results, recent designs have shown that high affinity analogs can be developed through C-terminal analogs dimerized with disulfide or lactam bridges. This review surveys NMR studies of NPY and its analogs with particular reference to the use of NMR data in molecular modeling of the solution structure.
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Archer B, Irwin D, Jensen K, Johnson ME, Rorie J. Depot medroxyprogesterone. Management of side-effects commonly associated with its contraceptive use. JOURNAL OF NURSE-MIDWIFERY 1997; 42:104-11. [PMID: 9107118 DOI: 10.1016/s0091-2182(96)00135-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Depot medroxyprogesterone acetate is one of the most popular, effective methods of contraception used in the United States. Many women experience unpleasant side effects from this method, including episodic vaginal bleeding, hair loss, depression, and weight gain. This Clinical Practice Exchange describes the treatment strategies for these side-effects used by nurse-midwives from a variety of settings and locales. Contraceptive use can be more acceptable for many women if they are better able to cope with unpleasant side effects of the method. This Clinical Practice Exchange provides knowledge to enhance client coping.
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Lu CL, Yu B, Basford JR, Johnson ME, An KN. Influences of cane length on the stability of stroke patients. JOURNAL OF REHABILITATION RESEARCH AND DEVELOPMENT 1997; 34:91-100. [PMID: 9021629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The purpose of this study was to investigate the influence of cane length on the standing and walking stability of stroke patients. Ten stroke patients were used as subjects and evaluated by using two different cane lengths based on the measurements of the distance from distal wrist crease to the ground (WC cane), and the distance from greater trochanter to ground (GT cane). Force plates were used to determine the center of pressure (COP). The maximum sways, the total travel distances, and the mean travel speeds of the COP were analyzed for each patient standing and walking with and without canes. It was found that the total travel distance and the mean travel speed of the COP in the medial-lateral (M-L) direction were significantly lower when standing with a cane than when standing without one. It was also found that the values of these parameters and the maximum sways of the COP in both anterior-posterior (A-P) and M-L directions were significantly lower when standing with the WC cane than when standing with the GT cane. No significant difference was found in the maximum M-L sway, the total travel distance, and the mean travel speed of the COP in walking. These results suggest that the standing stability of stroke patients is improved by using canes, especially by using a WC cane, although no significant influence of using canes on the walking stability was detected. Based on the results of this study, the vertical distance from the wrist crease to ground is recommended as the appropriate cane length for stroke patients.
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Gao S, Oh DH, Broadbent JR, Johnson ME, Weimer BC, Steele JL. Aromatic amino acid catabolism by lactococci. ACTA ACUST UNITED AC 1997. [DOI: 10.1051/lait:1997325] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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