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K D Lewis

Publications and source records attributed to K D Lewis.

13 recordsLinked to original sources
PubMed2001

Transesophageal echocardiography in the anesthetic management of total hip arthroplasty.

Total hip arthroplasty is a common procedure in the elderly and thromboembolism continues to be a cause of mortality and morbidity associated with this procedure. When properly diagnosed and treated the mortality rate from pulmonary embolism can be reduced significantly. Transesophageal echocardiograpic (TEE) detection of central pulmonary artery thromboemboli in patients with severe pulmonary embolism has been reported to have a sensitivity of 96.7% and a specificity of 88%. However TEE is not universally available due to its cost and expertise that is required. Taking into consideration its cost/effectiveness we suggest that in patients undergoing the cement type of total hip arthroplasty who are cardiopulmonary compromised, debilitated or elderly the use of TEE is indicated.

Anesthesia↗
PubMed2000

Early intervention and school nursing practice.

The most vital and critical period for early intervention is in the first 3 years of life. The school nurse working in an early childhood program plays a pivotal role in assessing and meeting the health and developmental needs of very young children and their families. This article discusses early intervention, as defined by federal law, as an age-related service delivered within a family-focused, multidisciplinary, interagency, and collaborative model. An assessment framework for school nurses working with this population is described, which includes physical, social, and emotional domains. Identifying children early and then providing needed interventions and services will assist at-risk children in realizing their developmental potential.

Child, Preschool↗
PubMed1997

Mental health in schools: expanded opportunities for school nurses.

Emerging trends are reshaping the work of school nurses and other school service personnel. With respect to direct service and consultation, school nurses increasingly are called upon to deal with psychosocial and mental health problems. Beyond that, school nurses must continue to actuate their roles as advocates, catalysts, brokers, and facilitators of the type of reforms that can effectively address barriers to student learning and promote healthy development. Continuing education is seen as key to enabling school nurses to build capacity for such roles and functions. The newly formed Center for Mental Health in Schools at the University of California, Los Angeles (UCLA) hopes to be of assistance in this respect. This presentation highlights the Center's orientation to mental health in schools and offers a draft outline for related continuing education.

Community Mental Health Services↗
PubMed1996

Rat hepatoma L35 cells, a liver-differentiated cell line, display resistance to bile acid repression of cholesterol 7 alpha-hydroxylase.

A stable hepatoma cell line (L35 cells) showing an activation of the cholesterol 7 alpha-hydroxylase gene (CYP7) that had been silent in the parental hepatoma cell line (H35 cells) was used to examine the influence of bile acids on its gene expression and activity. L35 cells were found to concentrate taurocholate from the culture medium, without any significant effect on the expression of 7 alpha-hydroxylase. At physiologic levels (up to 100 microM), CYP7 mRNA expression was not repressed by any bile acid. At supra-physiologic levels (1 mM), the more hydrophobic dihydroxy bile acids, taurodeoxycholate and taurochenodeoxycholate, decreased CYP7 mRNA without decreasing the relative abundance of beta-actin mRNA. Similar results were obtained by culturing cells with sodium dodecylsulfate (50 microM). The medium of L35 cells treated with either taurochenodeoxycholate (1 mM), taurodeoxycholate (1 mM), or sodium dodecylsulfate (50 microM) contained significantly greater activities of two cytosolic enzymes, lactate dehydrogenase and phosphoglucose isomerase, indicating a cytotoxic response. Activation of protein kinase C by phorbol esters decreased the expression of 7 alpha-hydroxylase mRNA without evidence of cytotoxicity; therefore, the inability of L35 cells to show bile acid repression cannot be ascribed to a lack of an effect by this secondary messenger system. In addition, insulin decreased and dexamethasone increased 7 alpha-hydroxylase mRNA without increasing the release of the cytoplasmic enzyme markers. The combined data suggest that L35 cells are resistant to repression of CYP7 gene expression by bile acids, but display physiologic expression to hormones and protein kinase C activation.

Animals↗
PubMed1993

In vivo dimeric association of class I MHC heavy chains. Possible relationship to class I MHC heavy chain-beta 2-microglobulin dissociation.

Class I MHC molecules have been thought to occur in vivo both as class I MHC heavy chain-beta 2-m heterodimers, which are or are not associated with antigenic peptide, and as free class I MHC heavy chains. Class I MHC molecules are now found also to occur in another type of structure: a heavy chain-heavy chain dimer. Biochemical studies show that heavy chain dimers are disulfide-linked via a conserved cytoplasmic domain cysteine. H-2Ld, H-2Db, and H-2Dd class I dimers fail to react with certain alpha 1 and alpha 2 domain-specific antibodies. Furthermore, although beta 2-m-specific antibodies coprecipitate class I MHC heavy chains, they do not coprecipitate class I MHC heavy chain dimers. Pulse-chase studies show that heavy chain dimer formation occurs at different points in the biosynthesis of class I MHC molecules in beta 2-m+ and beta 2-m- cells: in beta 2-m+ cells, heavy chain dimers form after the class I molecules have traversed the medial Golgi cisternae, whereas in beta 2-m- cells they form immediately. Culturing of beta 2-m+ cells with exogenous beta 2-m prevents the formation of H-2Ld/Db heavy chain dimers. We conclude that dimer formation occurs as a consequence of loss or unavailability of beta 2-m. Class I MHC heavy chain dimerization may provide a mechanism for removal of immunologically dysfunctional molecules.

Amino Acid Sequence↗
PubMed1991

Pathophysiology of prenatal drug-exposure: in utero, in the newborn, in childhood, and in agencies.

Medical communities are documenting an increase in the numbers of infants being born with prenatal drug exposure. Medical, educational, and social agencies are serving large numbers of these infants, toddlers, and their families. These infants and toddlers constitute a population whose short-term and long-term needs have not been adequately identified or addressed in the health, social, emotional, or developmental domains. This article discusses the pathophysiology in prenatal drug exposure and the role of the nurse when providing services to these infants, toddlers, and their families.

Child↗
PubMed1990

Prekallikrein deficiency in a family of Belgian horses.

A 7-year-old Belgian stallion hemorrhaged excessively after castration; the hemostatic mechanism was investigated. The horse had normal one-stage prothrombin time and markedly prolonged activated partial thromboplastin time (APTT). Results of intrinsic coagulation factor assays were all normal with the exception of prekallikrein activity, which was markedly reduced (less than 1% activity; value for control population, 63 to 150%). Two of this horse's full siblings, a brother and sister, had markedly prolonged APTT and low prekallikrein values (2.5% and less than 1%, respectively). The addition of plasma from a normal equine plasma pool corrected the prolonged APTT in the 3 Belgian sibling with low prekallikrein activity. Prekallikrein activity in 10 other closely related Belgian horses ranged between 12.5 and 64% (mean, 29.3%), compared with 63 to 150% (mean, 91%) in 10 mixed-breed horses. In the 3 Belgian siblings with low prekallikrein activity, the APTT approached normal after prolonged incubation (15 minutes) with the contact activator and in response to addition of an ellagic acid activator. The 3 Belgian siblings with low prekallikrein activity may be homozygous for prekallikrein deficiency, whereas the other close relatives may be heterozygous for the genetic defect.

Animals↗
PubMed1990

Activated T cells transcribe an alternatively spliced mRNA encoding a soluble form of Qa-2 antigen.

Among the best characterized non-classical mouse major histocompatibility antigens are the Qa-2 molecules. These proteins can serve as targets for allogenic cytotoxic T cells and as signal transducing molecules. They are structurally similar to H-2 transplantation antigens in their N-terminal and beta 2-microglobulin binding domains but differ at their C-termini. While the H-2 antigens span the cell membrane, the Qa-2 molecules are attached to the cell surface via phospholipid anchors. The genetic information encoding this attachment is contained in exon 5. In concanavalin A activated splenocytes the expression of membrane bound Qa-2 antigens declines and, simultaneously, soluble forms of Qa-2 molecules are secreted. We demonstrate here that the soluble Qa-2 polypeptides are translated from alternatively spliced mRNAs lacking exon 5, while the membrane forms are encoded by the full-size transcripts. In cultured cells the alternative splicing of the Qa-2 message is induced by T-cell activation splicing of the Qa-2 message is induced by T-cell activation with concanavalin A. The canonical mRNA encoding the membrane form of Qa-2 predominates in unstimulated mouse tissues but the cultured cell lines, like activated T cells, express enhanced levels of the truncated mRNA. In some cell lines almost all Qa-2 transcripts lack exon 5. For example, in L cells, mRNAs encoding soluble Qa-2 molecules are at least 10 times more abundant than Qa-2 transcripts encoding phospholipid anchored antigens. These findings are discussed in terms of potential functions of membrane bound and secreted Qa-2 molecules.

Amino Acid Sequence↗
PubMed1985

Molecular characterization of novel H-2 class I molecules expressed by a C3H UV-induced fibrosarcoma.

Two novel class I-like molecules expressed on tumor 1591, a C3H UV-induced fibrosarcoma, are biochemically characterized using two-dimensional gel electrophoresis, a cross-blocking RIA, and tryptic peptide mapping. One novel molecule that reacts with CP28, a syngeneic tumor-specific monoclonal antibody, appears mosaic because it possesses characteristics of both Kk and Dk class I molecules. The second molecule is closely related but not identical to the bona fide Ld molecule expressed on BALB/c spleen. Thus 1591 expresses at least two novel class I molecules and is vigorously rejected by normal C3H mice, while a variant tumor derived from 1591, termed AS7, does not express these two class I molecules although it still expresses Kk and Dk. The significance of these observations to the immunobiology and genetics of the UV-induced fibrosarcoma system is discussed. Speculations on the role that the major histocompatibility complex may play in the immunosurveillance of neoplasms are also presented.

Animals↗
PubMedDate not supplied

An empirical classification of drinking patterns among alcoholics: binge, episodic, sporadic, and steady.

Steady (daily, continuous) versus nonsteady (binge, episodic, bout, intermittent) drinking pattern have been influential Jellinek's (1960) formulation of delta and gamma drinkers, and are used as variables in various typological systems and drinker profiles. However, definitions of drinking patterns vary widely across studies, and most studies rely on one self-report item to establish a subject's pattern. To systematize and empirically test drinking-pattern schemas, we developed detailed definitions of binge, episodic, sporadic, and steady drinking patterns. A computer algorithm was written in SAS to classify 94 male alcoholics participating in outpatient conjoint therapy, using 6-month pretreatment drinking data from the Timeline Followback Interview. The final classification was: 3 (3%) binge, 33 (35%) episodic, 12 (13%) sporadic, and 40 (43%) steady drinkers. Six (6%) were unclassifiable (due to too few drinking days or too many interruptions to the pattern) by the computer. Episodic, sporadic, and steady drinkers did not differ in demographics, alcohol-related consequences, global psychological distress, or marital satisfaction. Steady drinking was associated with later onset of drinking problems (> 25), while episodic and sporadic drinking were associated with earlier onset. These results are contrary to current use of "binge drinking" as a variable associated with Type 1 alcoholism. Predictive validity analyses indicated that steady drinkers continued to drink more frequently than episodic and sporadic drinkers during treatment and 6 months posttreatment. Also, preliminary data indicate that pretreatment drinking pattern may be predictive of similar within-treatment urge-to-drink patterns. Implications for research and treatment are discussed.

Adult↗
PubMedDate not supplied

The care of infants menaced by cocaine abuse.

The newborn's symptoms of prenatal drug exposure threaten attachment. Consequently, psychosocial progress is impeded. Early intervention provides hope for these infants.

Cocaine↗