Biomedical subjects

C Baker

Publications and source records attributed to C Baker.

At least 73 records · Page 4Linked to original sources

PubMed1995

The development of the self-care ability to detect early signs of relapse among individuals who have schizophrenia.

A qualitative study using interpretive interactionism investigated how individuals with schizophrenia develop an ability to detect early signs of relapse. A purposive sample of 15 respondents were interviewed about their illness experiences. Three sequential processes were identified. Responding reactively to psychic pain, initiated by a desire to escape from overwhelming distress, resulted in the differentiation of tolerable and intolerable pain. Refining perceptions of psychic pain followed and resulted in the identification of specific thoughts, feelings and behaviors associated with different levels of distress. Finally, actively reducing psychic pain resulted in a proactive surveillance for specific signs of increasing distress.

Adolescent↗

PubMed1995

Core temperature control in the management of CNS lesions.

Renewed interest in the regulation of core temperature as a means of treating central nervous system disease has been fueled by a wealth of literature describing the physiology of lowered core temperature. Hypothermia is now recognized for its anesthetic and cerebroprotective effects and is being applied in an increasing number of clinical paradigms.

Body Temperature↗

PubMed1995

Diagnostic criteria for screening headache patients for temporomandibular disorders.

Patients with temporomandibular disorders frequently suffer from headache. The purpose of this study was to develop a simple screening exam which would allow the physician to identify headache patients with coexisting temporomandibular disorders. Twenty-eight migraine and 27 tension headache patients were identified by a board certified neurologist and then were examined by a dentist for signs of temporomandibular disorders. These patients were then compared to 63 patients with temporomandibular internal derangements and 62 patients with myofascial pain dysfunction. Comparisons of the clinical signs showed that the temporomandibular internal derangement and myofascial pain dysfunction patients differed significantly from the headache patients in regards to specific signs of jaw dysfunction. The presence of reciprocal clicking of the temporomandibular joint or pain with maximum jaw opening and pain upon palpation of the temporomandibular joint distinguished temporomandibular internal derangement patients from headache patients. These criteria have a sensitivity of 92% and specificity of 91%. Pain on palpation over the temporomandibular joint, or pain with maximum jaw opening using passive stretch, and pain with lateral movement of the jaw, distinguished myofascial pain dysfunction patients from headache patients. These criteria have a sensitivity of 77% and specificity of 85%. By using these screening tests, the physician can identify the concurrent existence of temporomandibular disorders in headache patients and triage the patient to a clinician knowledgeable in the diagnosis and treatment of temporomandibular disorders for further evaluation.

Cross-Sectional Studies↗

PubMed1995

A functional status scale for measuring quality of life outcomes in head and neck cancer patients.

Increased survival rates and disease control dictate that quality of life after treatment for head and neck cancer be evaluated. A disease-specific measure was developed from interviews with 115 patients, and items reflect the terminology used by the patients to describe treatment-related problems and concerns. Validity and reliability of this self-report scale were tested with 172 head and neck cancer patients and 30 patients who had breast and gynecological cancers. Discriminate validity was excellent. Convergent validity of the scale was demonstrated by Pearson correlations of 0.68 with a general health status measure, 0.68 with the Karnofsky Performance Scale, and 0.76 with the Performance Status Scale for Head and Neck Cancer Patients. Reliability as measured by Cronbach's alpha was 0.88. Analysis of variance demonstrated that the scale was sensitive to differences in stage of disease (p = 0.017) and extent of first surgery (p = 0.001) in this cohort of head and neck cancer patients. Psychometric evaluation indicates that the scale could be used as an outcome measure between groups at one point in time, but future research is needed to establish the scale's sensitivity to positive and negative changes in functional status for longitudinal studies.

Adult↗

PubMed1994

The effects of ozone exposure on lactate dehydrogenase release from human and primate respiratory epithelial cells.

Ozone is the most persistent, wide-spread air pollutant in the United States. Over one half of the population of the US lives in cities or suburban areas which do not meet the National Ambient Air Quality Standard for ozone which is 0.12 ppm averaged over 1 h. Controlled laboratory exposures of human subjects have shown that ozone exposure produces decreased pulmonary function, hyperresponsiveness to inhaled methacholine, inspiratory pain, and airway inflammation as assessed by bronchoalveolar lavage. However, the cellular mechanisms responsible for such effects are incompletely known. The present study examined the effects of ozone exposure at 0.50 ppm for 3 h on three types of cultured respiratory epithelial cells; primary cultures of human nasal cells and primate bronchial cells, and the A549 type II pneumocyte-derived cell line. Cells were grown to confluent monolayers in plastic 6-well plates and then exposed to ozone or filtered air on a tilting platform over a heated water bath. Lactose dehydrogenase release was significantly increased following ozone exposure of all cell types; a 75% increase from human nasal cells (P = 0.0002), a 79% increase from primate bronchial cells (P = 0.003), and a 69% increase from A549 cells (P = 0.02). These data suggest that even brief ozone exposure causes membrane injury to cultured human respiratory epithelial cells.

Adolescent↗

PubMed1994

Studies of the epidemiology of dementia: comparisons between developed and developing countries.

By the year 2025, 68% of the world's population aged 65 and above, nearly 277 million people, will be residing in developing countries. The less industrialized nations have been the least studied to date, and may yield significant new information about the etiology and risk factors for Alzheimer's disease (AD) and other dementias. Although it is readily apparent that cross-national and cross-cultural comparisons are desirable, these can be meaningful only if based on comparable methodology. In this work we will discuss some general conceptual and methodological issues regarding epidemiological studies of dementia in developing countries. The topics discussed include community-based screening for dementia, screening instruments and their application in cross-cultural studies, steps in standardization of new or modified neuropsychological tests, and some special considerations in studying uneducated/illiterate populations.

Aged↗

PubMed1994

Sexual communication is associated with condom use by sexually active incarcerated adolescents.

PURPOSE: Incarcerated adolescents are at increased risk for infection by sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV). Moreover, condom use by this population is extremely low. Although interpersonal variables such as sexual communication have been found to be associated with condom use in other populations, few researchers have investigated this relationship among adolescents requiring detention in juvenile facilities. The present study investigated the relationship between communication about sexual history and incarcerated adolescents' condom use. METHODS: We used multivariate logistic regression techniques to analyze interview data from a predominantly Latino sample of 2,132 sexually active adolescents detained in Los Angeles County Juvenile Hall. RESULTS: Despite high numbers of lifetime sexual partners, a substantial majority of respondents (67%) reported that they never used condoms during sexual intercourse. Respondents who communicated with their sex partner(s) about each others' sexual history were significantly more likely to use condoms during sexual intercourse. Adolescents who reported that they knew someone with AIDS were also more likely to use condoms. CONCLUSIONS: Interventions designed to increase condom use among sexually active incarcerated adolescents should include a component addressing sexual communication practices. More research is needed on the ways in which adolescents learn to communicate about sex.

Adolescent↗

PubMed1994

Synthesis of interleukin-1 alpha, interleukin-6, and interleukin-8 by cultured human nasal epithelial cells.

Nasal epithelium forms the initial barrier between the environment and the respiratory system and may be a potential source of proinflammatory interleukins, which contribute to the pathophysiology of allergic and nonallergic rhinitis. To explore this possibility, epithelium and cultured human nasal epithelial cells from nasal turbinates of patients undergoing surgery for treatment of upper airway obstruction were examined for the spontaneous expression of interleukin (IL)-1 alpha, IL-1 beta, IL-6, and IL-8. Human nasal epithelial cell lysates and culture supernatants were assayed by two-site ELISAs specific for IL-1 alpha, IL-1 beta, IL-6, or IL-8. Maximum concentrations of these cytokines in supernatants ranged from approximately 0.2 to 2 ng/ml for IL-1 alpha, 1.5 to 7 ng/ml for IL-6, and 100 to 3000 ng/ml for IL-8. IL-1 alpha was predominantly cell-associated, whereas most of the IL-8 and all of the IL-6 were detected in the supernatant. Little or no IL-1 beta was detected by ELISA in the supernatants or cell lysates. Whole tissue turbinates and isolated epithelium were also examined for IL-1 beta, IL-6, and IL-8 mRNA expression by Northern blot analysis. IL-6 and IL-8 mRNAs were detected, whereas IL-1 beta mRNA was not. Furthermore, IL-6 and IL-8 release from human nasal epithelial cell cultures was enhanced by addition to the cultures of lipopolysaccharide, and IL-6 release was inhibited by polymyxin B. Thus human nasal epithelium may be a major source of IL-1 alpha, IL-6, and IL-8 in allergic and nonallergic rhinitis. Production of those proinflammatory cytokines by epithelial cells of the nasal and sinus mucosa may contribute to the pathologic and clinical events that occur in these diseases.

Adolescent↗

PubMed1994

Arthroscopic treatment of anterolateral ankle impingement.

Fifty-five ankle arthroscopies performed for anterolateral ankle impingement between January 1987 and April 1992 were reviewed for functional outcome and patient satisfaction. There were 33 men and 22 women with an average age of 34 years (range 20-67). All patients reported a previous history of ankle injury, and 60% of the patients had at least one ankle sprain. At an average follow up of 2.6 years (range 1.0-4.5), 87% of the patients had good/excellent results, 98% were satisfied, and 84% returned to their previous sports.

Adult↗

PubMed1994

Resettlement without the support of an ethnocultural community.

The purpose of this phenomenological study is to describe the lived experience of immigrating to a region where there is no ethnocultural community of one's culture. Twenty culturally isolated immigrants to Moncton, New Brunswick, Canada, of different ethnic origins were interviewed in depth about their resettlement experience: the Giorgi modification of the phenomenological method was used to analyse these data. The findings suggest that being a culturally isolated immigrant entails a sense of discontinuity between the past and the present and produces a period of heightened sensitivity to others. Informants felt propelled from their country into an alien environment and were suddenly immersed into a new culture. Their emotional energies were directed towards getting a foothold in their new society. This was a highly stressful process that was both encouraged and discouraged by pervasive thoughts of the future which permeated the participants' existence.

Adult↗

PubMed1994

Prevalence of Neisseria meningitidis relatively resistant to penicillin in the United States, 1991. Meningococcal Disease Study Group.

To estimate the prevalence of Neisseria meningitidis relatively resistant to penicillin in the United States, antimicrobial susceptibility testing was performed on all US meningococcal isolates submitted to the Centers for Disease Control and Prevention in 1991, including isolates identified through population-based surveillance for invasive meningococcal disease in selected areas of the United States. Three of the 100 isolates tested had MICs of penicillin of 0.125 microgram/mL. All were serogroup B, beta-lactamase-negative, and unique by multilocus enzyme electrophoresis subtyping. None of the 3 patients had been treated solely with penicillin; all recovered completely. About 4% of the isolates obtained from the population-based surveillance system were relatively penicillin-resistant. Given the low prevalence and uncertain clinical significance of infection with these organisms, routine susceptibility testing of meningococcal isolates is not indicated at this time; however, continued surveillance is necessary to monitor trends in antimicrobial susceptibility of meningococci in the United States.

Disease Outbreaks↗

PubMed1993

Cytokines and eosinophil-derived cationic proteins upregulate intercellular adhesion molecule-1 on human nasal epithelial cells.

BACKGROUND: Allergic and nonallergic rhinitis with eosinophilia syndrome are characterized by tissue eosinophilia and nasal mucosal injury. Recently, it has been shown that the adherence of eosinophils and other leukocytes to epithelial cells is mediated by intercellular adhesion molecule-1 (ICAM-1) and related adherence-promoting glycoproteins. METHODS: In this study we examined the constitutive expression of ICAM-1 on human nasal epithelial cells (HNECs), and the effects of interferon-gamma, tumor necrosis factor-gamma eosinophil major basic protein, and eosinophil cationic protein on the regulation of ICAM-1 expression on these cells. Similar studies were performed with A549 pneumocytes as comparative epithelial cells. RESULTS: Constitutive expression of ICAM-1 was significantly higher on cultured HNECs than on A549 cells, although nasal epithelial cells in tissue specimens did not demonstrate detectable levels of ICAM-1. This spontaneous expression of ICAM-1 on cultured HNECs may explain the unique susceptibility of the nasal mucosa to rhinovirus infection, because ICAM-1 is the epithelial cell receptor for most rhinoviruses. Physiologic concentrations of major basic protein and eosinophil cationic protein stimulated significant upregulation of ICAM-1 on HNECs, which was comparable to that produced by interferon-gamma and tumor necrosis factor-alpha. In contrast, these eosinophil constituents did not stimulate ICAM-1 upregulation on A549 alveolar epithelial cells, although A549 cells did respond to interferon-gamma and tumor necrosis factor-alpha. CONCLUSION: The observation that eosinophil products upregulate ICAM-1 on HNECs suggests a positive feedback mechanism, in which the products released from migrating eosinophils might promote additional HNEC-leukocyte adherence by enhancing interactions between leukocyte beta 2 integrins (CD11/18) and nasal epithelial ICAM-1.

Blood Proteins↗

PubMed1993

The cost of not wearing seat belts. A comparison of outcome in 3396 patients.

Data from the North Carolina Trauma Registry were analyzed to determine the effect of seat belt usage on outcome in motor vehicle accidents. Of 6237 persons involved in motor vehicle accidents, data on seat belt usage were available for 3396. Of these, 1916 were not and 1480 were wearing seat belts. The mean hospital charge in belted patients was $10,500 +/- $18,200; and in unbelted patients, $15,250 +/- $26,300 (p < 0.001). The total hospital charges were $23 million for the 1508 patients not wearing seat belts. If the unbelted patients had outcomes similar to belted patients, the charges resulting from caring for the 1508 patients would have been $15.8 million, a potential savings of $7.2 million. There were 135 deaths among the unbelted patients (7.0%) and 47 deaths among the belted patients (3.2%) (p < 0.001). A similar projection of belted outcome for unbelted patients suggests that seat belt usage could have reduced the unbelted mortality rate by over one half. Patients wearing seat belts also had significantly shorter hospital stays, fewer days in the intensive care unit, and fewer days on the ventilator (p < 0.001). Seat belt usage is associated with a significant decrease in mortality rate, hospital charges, length of stay, intensive care unit stay, and ventilator requirements. Seat belts could have saved at least 74 lives and 7.2 million dollars during the period from October 1, 1987 to July 1, 1989 in patients seen in the seven trauma centers in North Carolina.

Accidents, Traffic↗

PubMed1993

Head CT scanning versus urgent exploration in the hypotensive blunt trauma patient.

In hypotensive blunt trauma patients with a diminished level of consciousness, it may be difficult to decide whether to proceed with immediate head CT scanning or urgent laparotomy or thoracotomy. The purpose of this study was to determine the frequency of emergency craniotomy and urgent laparotomy or thoracotomy in a group of 734 blunt trauma patients with initial hypotension (BP < 90 mm Hg systolic) admitted to the eight level I and II trauma centers in North Carolina. The mean initial systolic blood pressure was 64 +/- 26 mm Hg, and the mean Trauma Score was 8 +/- 5.8. Serious head injury (AIS head > or = 3) was present in 40% (293 of 734). Of 734 patients studied, 9.4% (69 of 734) died in the emergency department. Head CT scanning was performed on 47% (344 of 734) and produced positive results for 26% (202 of 734). Emergency craniotomy for intracranial hemorrhage was performed on 2.5% (18 of 734) (ten subdurals, three epidurals, and five other intracranial hemorrhages). Twenty-one percent (154 of 734) underwent urgent laparotomy, thoracotomy, or both. Overall hospital mortality for hypotensive blunt trauma patients was 36% (263 of 734). Although serious head injury occurs commonly (40%) in hypotensive blunt trauma patients, frequency of urgent laparotomy (21%) is 8.5 times greater than emergency craniotomy for intracranial hemorrhage (2.5%). This information may be used by trauma teams in prioritizing care for hypotensive blunt trauma patients.

Abdominal Injuries↗

PubMed1993

The comparison of patients suffering from temporomandibular disorders and a general headache population.

The purpose of this study was to examine the possible association of signs and symptoms of temporomandibular disorders relative to headache. Fifty-six sequential patients referred to the Headache Institute of Minnesota for evaluation and treatment of migraine and tension headaches were examined for signs and symptoms of temporomandibular disorders. The results of the examination of headache patients were compared to patients suffering from myofascial pain dysfunction and/or TMJ internal derangements from the TMJ and Craniofacial Pain Clinic at the University of Minnesota. Finally the migraine and tension headache patients were compared to each other and an asymptomatic population. Results indicate that patients with temporomandibular disorders exhibit significantly more jaw dysfunction and pericranial muscle tenderness than migraine and tension headache patients. Migraine and tension headache patients were found to have similar amounts of pericranial muscle tenderness. Migraine and tension headache patients exhibited significantly more pericranial and neck muscle tenderness than a general population.

Analysis of Variance↗

PubMed1993

Partial characterization of proteoglycans synthesized by human gingival epithelial cells in culture.

Proteoglycans (PGs) were extracted from the [35S]-sulfate labelled medium and cell layer of proliferating human gingival epithelial cells and analyzed by ion exchange and molecular sieve chromatography, and by SDS-PAGE. The majority of the incorporated radioactivity secreted into the medium eluted from a DEAE Sephacel ion exchange column as a single peak at 0.44 M NaCl with a small shoulder at 0.52 M NaCl. This material, when chromatographed on Sepharose CL-6B contained two species--a quantitatively major peak at K(av) = 0.30 (M(r) congruent to 235,000 on SDS-PAGE) and a quantitatively minor peak at K(av) = 0.39. The major peak was sensitive to alkaline borohydride, shifting to K(av) = 0.45, and nitrous acid degradation, indicating the presence of heparan sulfate PG with glycosaminoglycan chains with M(r) congruent to 26,000. The minor peak is chondroitin/dermatan sulfate PG with glycosaminoglycan chains of M(r) = 22,200 as indicated by sensitivity to alkaline borohydride (shifting to K(av) = 0.48) and chondroitin ABC lyase digestion. The [35S]-sulfate labelled material from the cell layer eluted in a broad peak between 0-0.50 M NaCl from DEAE Sephacel. Chromatography of this material on Sepharose CL-6B revealed the presence of three peaks at K(av) = 0.20, 0.31, and 0.75. The largest peak (K(av) = 0.20 and M(r) congruent to 245,000 on SDS-PAGE) shifted elution position to K(av) = 0.50 after alkaline borohydride treatment and was completely sensitive to nitrous acid degradation. These results indicate that this peak contains heparan sulfate PG with glycosaminoglycan chains of M(r) congruent to 20,000. Two peaks containing [35S]-sulfate labelled glycosaminoglycan chains were detected by chromatography of the cell layer extract over Sepharose CL-6B with K(av)S = 0.42 (M(r) congruent to 30,500) and 0.75 (M(r) congruent to 5300). The larger peak was predominantly chondroitin/dermatan glycosaminoglycan as indicated by susceptibility to chondroitin ABC lyase while the chains at K(av) = 0.75 were predominantly heparan sulfate with 83% susceptibility to nitrous acid. These results indicate that cultured human gingival epithelial cells synthesize and secrete principally heparan sulfate PGs with small amounts of chondroitin/dermatan sulfate PGs. This work will serve as a basis for future studies designed to examine those factors involved in regulation of PG synthesis by these cells.

Cells, Cultured↗

PubMed1993

Finding meaning in chronic illness as the key to self-care.

Self-care is an important element in the successful management of a long-term illness. However, people with chronic illnesses are often reluctant to adopt self-care behaviors. The purpose of this grounded theory study was to investigate the evolution of a readiness to self-manage a nonfatal chronic illness. A purposive sample of twelve individuals with a nonfatal illness whose course can be controlled by treatment were interviewed. In addition, the primary nurse caring for each informant at home was also interviewed. The findings indicate that the key process in self-care readiness was finding meaning in chronic illness. This process involved assenting to the illness and reframing its implications positively. It allowed informants to make sense of self-care teaching and to perceive themselves as self-care agents having some control over their illness course.

Adaptation, Psychological↗

PubMed1993

Injury severity grading in trauma patients: a simplified technique based upon ICD-9 coding.

UNLABELLED: The purpose of this study was to develop a simplified method of stratifying patient risk of death based on ICD-9 codes. METHODS: Data were obtained from a statewide trauma registry. A mortality risk ratio (MRR) was derived from a "training" subset by calculating a mortality rate for each ICD-9 code of interest. The independent variables of interest included TS, ISS, and MRRs (for the 1st & 2nd Dx, 1st op, & E code). RESULTS: (n = 37,100). When the 1st Dx and ISS were used as candidate variables in stepwise multivariate modeling, the MRR for the 1st Dx was the first variable to be entered into the model (1st Dx partial R2 = 0.37, ISS partial R2 = 0.02). CONCLUSION: This study shows that the 1st Dx is a better predictor of outcome than ISS. Since ICD-9 codes are more easily obtained and are better predictors of outcome, this study suggests that they may supersede the use of the ISS in injury severity scoring.

Adolescent↗