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D Hanson

Publications and source records attributed to D Hanson.

At least 37 records · Page 2Linked to original sources
PubMed1996

Investigation of authorship in facilitated communication.

We examined whether facilitated communication users, under controlled conditions, could transmit rudimentary information to a naive facilitator. Forty-three students across 10 classrooms were shown a single randomly selected word with their facilitator out of the room. The facilitator then entered the room and asked the student to type the word, which was recorded exactly as typed and later evaluated; approximately 3,800 attempts were conducted over a 6-week period. Results showed that (a) under controlled conditions, some facilitated communication users can pass accurate information and (b) measurement of facilitated communication under test conditions may be significantly benefitted by extensive practice of the test protocol, which could partially account for the inability of several past studies to verify facilitated communication-user originated output.

Adolescent↗
PubMed1995

How important is race/ethnicity as an indicator of risk for specific AIDS-defining conditions?

In order to examine differences in the prevalence of AIDS-defining conditions by race/ethnicity, we analyzed U.S. surveillance data for 203,470 adolescents and adults diagnosed with AIDS from 1988 through 1992. A number of AIDS-indicator conditions were more common among certain racial/ethnic groups. The prevalence of extrapulmonary tuberculosis was higher among blacks, Hispanics, Asians/Pacific Islanders, and American Indians/Alaskan Natives than among whites. The prevalence of isosporiasis and toxoplasmosis was higher among Hispanics than among blacks or whites. Furthermore, the likelihood of being diagnosed with extrapulmonary tuberculosis (TB), toxoplasmosis, or isosporiasis was generally higher among foreign-born than among U.S.-born persons of all racial/ethnic groups. The prevalence of all malignancies was higher among whites than among blacks or Hispanics. However, the magnitude of prevalence differences by race/ethnicity was reduced when we controlled for other demographic and exposure risk categories. Although race/ethnicity was significantly associated with the prevalence of a number of conditions, the relative frequency and patterns of AIDS-indicator conditions in different populations are probably most influenced by differences in (1) underlying prevalence or exposure to various etiologic agents causing these conditions, (2) diagnosis and reporting of conditions, and (3) access to care and therapy for HIV-related conditions.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Prophylaxis against Pneumocystis carinii pneumonia among children with perinatally acquired human immunodeficiency virus infection in the United States. Pneumocystis carinii Pneumonia Prophylaxis Evaluation Working Group.

BACKGROUND: Pneumocystis carinii pneumonia (PCP) remains a common and often fatal opportunistic infection among children infected with the human immunodeficiency virus (HIV). HIV-infected infants between three and six months of age are particularly vulnerable. Current guidelines recommend prophylaxis in children from birth to 11 months old who have CD4+ counts below 1500 cells per cubic millimeter. METHODS: We used national surveillance data to estimate the annual incidence of PCP among children less than one year old. We reviewed the medical records of 300 children given a diagnosis of PCP between January 1991 and June 1993 to determine why treatment according to the 1991 guidelines for prophylaxis against PCP either was not given or failed to prevent the disease. RESULTS: In our study the incidence of PCP in the first year of life among infants born to HIV-infected mothers changed little between 1989 and 1992. Among 7080 children born to HIV-infected mothers in 1992, PCP developed in 2.4 percent. Of 300 children with PCP diagnosed from January 1991 through June 1993, 199 (66 percent) had never received prophylaxis, and for 118 of those children (59 percent) exposure to HIV was first identified 30 days or less before the diagnosis of PCP. Among 129 children less than one year old, the CD4+ count declined by an estimated 967 cells per cubic millimeter (95 percent confidence interval, 724 to 1210 cells per cubic millimeter) during the three months before the diagnosis of PCP. Among infants in whom CD4+ counts were determined within one month of the diagnosis of PCP, 18 percent (20 of 113) had at least 1500 cells per cubic millimeter, a level higher than the currently recommended threshold for prophylaxis. CONCLUSIONS: In the United States the incidence of PCP among HIV-infected infants has not declined. If this infection is to be prevented, infants exposed to HIV must be identified earlier, and prophylaxis must be offered to more children than the guidelines currently recommend.

AIDS-Related Opportunistic Infections↗
PubMed1995

Changes in pulmonary function test results after 1 year of therapy as predictors of survival in patients with idiopathic pulmonary fibrosis.

The study group consisted of 58 patients with idiopathic pulmonary fibrosis (IPF) recognized between 1970 and 1991 who were treated for their pulmonary disease, survived for at least 1 year from the time of initiation of treatment, and had forced vital capacity (FVC) measurements at the time of diagnosis and 9 to 15 months later. Forty-four of the patients also had a single-breath diffusing capacity (Dsb) measured initially and after 9 to 15 months of treatment and 33 patients had an arterial blood gas, breathing room air at the time of diagnosis and 9 to 15 months into therapy. Patients' conditions were classified as improved, unchanged, or worse after the year of treatment based on each of the three pulmonary function tests. A > or = 10% increase in FVC, > or = 20% increase in Dsb, and > or = 5 mm Hg decrease in alveolar-arterial difference in oxygen partial pressure [P(A-a)O2] defined improved function. A > or = 10% decrease in FVC, > or = 20% decrease in Dsb, and > or = 5 mm Hg increase in P(A-a)O2 defined worse function. Patients with < 10% change in FVC, < 20% change in Dsb, and < 5 mm Hg change in P(A-a)O2 were regarded as having unchanged conditions. Kaplan-Meier survival plots and the Cox proportional hazard regression model were used to analyze survival time in relation to change in pulmonary function after 1 year of therapy. Patients with an improved or unchanged FVC at 1 year had no difference in survival (p = 0.75), but both showed enhanced survival compared with patients with a > or = 10% reduction in FVC with 1 year of treatment (p < 0.001). Patients with an improved or unchanged Dsb at 1 year also had no difference in survival (p = 0.21) but again, both showed enhanced survival compared with patients with > or = 20% decrease in Dsb with 1 year of treatment (p < 0.001). Changes in gas exchange after 1 year of treatment did not correlate with survival in the three groups. There was a trend for longer survival in improved patients compared with those with worsening gas exchange, but the p value was not significant at 0.17. We conclude that changes in the FVC and Dsb after 1 year of treatment are strongly predictive of duration of survival in patients with IPF.

Adult↗
PubMed1994

Comparison of dosage-dependent effects of beta-aminopropionitrile, sodium fluoride, and hydrocortisone on selected physical properties of cortical bone.

BAPN, sodium fluoride, and hydrocortisone are reported to induce altered mineralization states. Three separate sets of experiments, one set for each agent, were performed using male New Zealand white rabbits. In each experiment the rabbits were segregated into groups, each fed a specified weight-determined dose for 13 weeks and then sacrificed. Compact bone from the left femur and tibia were tested for density, composition, sonic velocity, longitudinal elastic modulus, equatorial diffraction spacing of mineralized collagen, diaphyseal cross-sectional area, and relative load stress. beta-Aminopropionitrile (BAPN) induced monotonic degradation of all properties at all dose levels, corresponding to the decreasing density with dosage level. The elastic moduli show a decrease; the equatorial diffraction spacing of the collagen increases. The cross-sectioned diaphysis resembled woven bone. The variability in properties increased with dosage. The total cross-sectional area for a given weight increased, implying that the decreased elastic properties were compensated for by a larger area to support the weight. There was a slight increase in average density and other properties for fluoride-treated rabbits, peaking at 20 mg/kg BW/day. For higher dosages the properties are degraded and the values were much lower at high fluoride dosages than for BAPN. There was no peak for the equatorial diffraction spacing, which increased with dosage. It is inferred that the fluorosed apatite is denser than normal apatitic mineral and therefore has a smaller specific volume. A greater weight fraction of fluorosed mineral has a smaller volume fraction than the equivalent normal apatitic mineral. The bone sections look more normal, except for the porosis. The total cross-sectional area decreases when the bone density increases and then increases as the density falls, again implying that the area required to support body weight depends on the magnitude of the elastic moduli. There was a small change in some of the properties of the bones of the hydrocortisone-treated rabbits, but the effects on others were undetectable within the uncertainty of the procedures. There was no change in the cross-sectional areas of the diaphyses.

Aminopropionitrile↗
PubMed1994

Omeprazole for the treatment of posterior laryngitis.

PURPOSE: To determine whether the patients with refractory posterior laryngitis respond to treatment with omeprazole. PATIENTS AND METHODS: Sixteen consecutive patients with persistent posterior laryngitis despite prior therapy with H2 blockers were recruited from outpatient university otolaryngology and gastroenterology practices. Patients received 6 to 24 weeks of omeprazole 40 mg qhs, which was increased to 40 mg twice a day for 6 weeks in four patients with continuing symptoms. Laryngoscopy, esophagoscopy, and esophageal/laryngeal symptom questionnaire were completed at entry to the study. Laryngoscopy and the questionnaire were repeated at the conclusion of the study. A follow-up questionnaire was completed at 6 weeks. RESULTS: Laryngoscopy scores improved from 4.44 to 1.94 (nonblinded otolaryngologist) and 4.31 to 1.88 (blinded otolaryngologist) (P < 0.05). Laryngeal and esophageal symptom indices improved from 13.94 and 9.00 to 3.00 and 0.38, respectively (P < 0.05). Symptom indices increased to 7.00 and 7.33, respectively, after the discontinuation of therapy (P < 0.05 compared with the conclusion of the study). One patient intolerant of omeprazole underwent fundoplication and was asymptomatic 6 weeks after surgery. Only 3 patients had esophagitis at entry. CONCLUSIONS: The signs and symptoms of posterior laryngitis improve with the administration of omeprazole and symptoms recur after discontinuation of therapy, suggesting that reflux is the underlying etiology. Patients with refractory symptoms, but intolerant of omeprazole, may benefit from antireflux surgery. Laryngoscopic findings of posterior laryngitis are often subtle, and many patients with posterior laryngitis do not have esophagitis.

Adult↗
PubMed1994

Skin care strategies in a skilled nursing home.

1. Pressure ulcers continue to be a serious problem in nursing home settings. They are significant as a source of discomfort and disability among nursing home residents, as well as a source of financial concern for the institutional agencies responsible for resident care. 2. Prevention and intervention at the earliest stages of pressure ulcer development offer the most effective approaches to mediating the human and economic costs imposed by pressure ulcers. 3. Strategies that are effective in reducing both the development and severity of pressure ulcers can be successfully implemented in long-term care settings. Further studies are needed that will provide additional support for the strategies and protocols used in this study.

Adolescent↗
PubMed1993

Anticoagulant activity of Hirulog, a direct thrombin inhibitor, in humans.

Hirulog (BG8967) is a direct thrombin inhibitor built by rational design using the protein hirudin as a model (Maraganore et al. [1990]; Biochemistry 29: 7095-101). In order to evaluate the therapeutic potential for hirulog in the management of thrombotic disease, the tolerability and anticoagulant activity of the agent were examined in a study of human volunteers. In a randomized, placebo-controlled study (n = .54), the intravenous infusion of hirulog over 15 min showed a rapid, dose-dependent prolongation of activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). There was a corresponding dose-dependent increase in plasma hirulog levels. The peptide was rapidly cleared with a half-life of 36 min and a total body clearance rate for the peptide of 0.43 l kg-1 h-1. Similar activity was observed following subcutaneous injection but with sustained pharmacodynamic and pharmacokinetic behavior. There was a significant correlation between pharmacokinetic and pharmacodynamic variables for both intravenous (r = 0.8, p < 0.001) and subcutaneous administration (r = 0.7, p = 0.002). To evaluate the possible interactions of aspirin on the tolerability and anticoagulant activity of intravenous hirulog, a cross-over design was employed in eight subjects. Aspirin administration did not modify the peptide's activity. At the administered dose of 0.6 mg kg-1 h-1 for 2 h, hirulog infusion prolonged APTT from 230 to 260% baseline. The infusion of hirulog in subjects who had received aspirin was not associated with any significant changes in the template bleeding time.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Cell washing versus immediate reinfusion of intraoperatively shed blood during abdominal aortic aneurysm repair.

Significant hematologic changes are known to occur following intraoperative autotransfusion of shed blood, but the clinical importance of cell washing prior to reinfusion has not been substantiated. To evaluate these changes and their relationship to the use of blood bank products and postoperative morbidity, 26 patients undergoing elective abdominal aortic aneurysm repair were prospectively randomized to reinfusion with washed shed blood or to the use of a collection system in which filtered, but unwashed, whole blood was reinfused intraoperatively. Each patient was evaluated with respect to standard metabolic and hematologic laboratory parameters preoperatively, immediately postoperatively, and 12 to 18 hours postoperatively. Patient demographic data were similar for both groups. Perioperative survival was 100% for both groups. Total blood loss and blood volume autotransfused were significantly greater in the unwashed cell group compared with the washed cell group (p = 0.00014 and p = 0.00011, respectively). Hemoglobin, fibrinogen, prothrombin time, and partial thromboplastin time levels were not significantly different between the two groups at any time perioperatively; fibrin split product and d-dimer levels were significantly higher in the unwashed cell group postoperatively (p = 0.016 and p < 0.001, respectively). Serum free hemoglobin levels were significantly higher in the immediate postoperative period in the unwashed cell group compared with the washed cell group (p = 0.0013); by 12 to 18 hours postoperatively, this difference was not significant. Haptoglobin levels were significantly lower in the unwashed cell group at both postoperative times (123 +/- 86 mg/dL versus 41 +/- 50 mg/dL, p = 0.0086; 102 +/- 66 mg/dL versus 24 +/- 36 mg/dL, p = 0.0001); however, there was no perioperative renal failure in either group. Furthermore, homologous blood product use was not significantly different between the two groups, with an average of 1.5 +/- 2.5 units of packed red blood cells given to patients in the unwashed cell group versus 0.8 +/- 1.7 units in the washed cell group (p = 0.419). Overall complications were higher and critical care and total hospital stays were longer in the unwashed cell group but did not result from autotransfusion of unwashed blood. We conclude that the intraoperative reinfusion of unwashed shed blood is safe and effective, causing transient hematologic abnormalities that normalize in the early postoperative period, and is not associated with increased mortality, or hematologic, cardiopulmonary, or renal complications.

Aged↗
PubMed1992

Skin problems: epidemiology of pressure ulcers in a skilled care facility.

The majority of nursing home residents have conditions that place them at risk for the development of pressure ulcers. Reported pressure ulcer prevalence rates range from 16% to 35%. Pressure ulcers are multifactorial in origin and necessitate ongoing vigilance by the entire health-care team. Associated risk factors include impairments of circulation, sensation, physical condition, nutrition, mobility, and activity. Stage I pressure ulcers frequently go unrecognized, yet their recognition is essential to prevent further damage. Comprehensive initial assessments of the skin and risk factors of pressure ulcer development at admission will allow for easier reassessment and comparison.

Aged↗
PubMed1991

Incidence and prediction of pressure ulcers in five patient care settings.

Pressure ulcers (PU), one example of an alteration in skin integrity, remain a prominent healthcare concern in all patient care settings. Incidence refers to the number of "new cases occurring over a given time period" (NPUAP, 1989, p. 26). Adult patients (n = 190) in five patient care settings who were assessed to be free of PUs on admission were followed over a specified period of time to assess the incidence of pressure ulcer development for each setting. Subjects each had a skin assessment, along with a risk assessment utilizing the Braden Scale. A demographic data form was also completed on each subject. Pressure ulcers developed post-admission in 18 (9%) patients, 11 of whom were acute care patients and eight of whom were patients in skilled care. No patients developed pressure ulcers in the rehabilitation, home care, or hospice settings. Incidence for acute care was 15% and 28% in skilled care. Braden predictor scores were also recommended for each setting and factors associated with pressure ulcer development were discussed.

Adult↗
PubMed1990

A computer program for analyzing bivariate flow karyotypes.

This article describes a computer program for analyzing bivariate flow karyotypes of human chromosomes stained with Hoechst 33258 (HO) and chromomycin A3 (CA). The karyotype first is divided into regions that contain chromosome peaks. The chromosomes that are associated with those areas are identified. The distributions in these areas then are fitted with mathematical functions of increasing complexity. The process starts by fitting a specified number of univariate Gauss functions to projections of the HO and CA distributions of each area. The final fit can include multiple bivariate Gauss functions, including a background function for debris subtraction. The results of one stage in the fitting process serve as seed values for the next, more complex step. Since the program autonomously estimates the starting values for the iterative fitting procedures, the fit results are insensitive to operator bias and the program will consistently converge to the same solutions. The resulting table of parameter values can be used to compare flow karyotypes to a reference data set.

Chromomycin A3↗
PubMed1990

Salivary gland tumors of the oral cavity.

Between 1961 and 1985, 62 patients with malignant salivary gland tumors of the oral cavity underwent surgery with curative intent at the University of California, Los Angeles (UCLA) Medical center. All patients had a minimum follow-up of 2 years. Fifty of 62 (81%) patients presented with T1-2 primary tumors. The tumors arose from the palate in 41/62 (66%) patients. The most common histologic type was adenoid cystic carcinoma comprising 34 of 62 (55%) cases. Radical resection was performed in 46 cases and wide local excision in 16 patients. Postoperative radiation therapy was used in 24 cases due to advanced stage and/or positive surgical margins. Results of treatment were analyzed by stage of disease, modes of treatment, histology, and surgical extent. Local control of small lesions reached 100% at 10 years with either radical resection alone or local excision. With residual tumor at the surgical margins, the incidence of local recurrence was 4/14 (29%) for those who received adjuvant radiation therapy and 5/10 (50%) for those who did not. The vast majority of mucoepidermoid carcinomas were early stage and low grade. These lesions had an excellent prognosis with a control rate of 100%. In contrast, there was a 29% (10/34) failure rate for adenoid cystic carcinoma. The 5-, 10-, and 15-year actuarial survivals for the whole group were 94%, 84%, and 73%, respectively. Our results indicate that for early stage disease, wide local excision may offer patients the chance to avoid the cosmetically and functionally debilitating effects of radical surgery without compromising treatment outcome. Adjuvant radiation therapy appears to reduce the local recurrence for those with residual tumor at the surgical margins.

Adolescent↗
PubMed1990

Long-wave ultraviolet light induces phospholipase activation in cultured human epidermal keratinocytes.

Long wave ultraviolet radiation (UVA) has been shown to play an important role in the overall response of skin to solar radiation, including sunburn, tanning, premature aging, and non-melanoma skin cancer. UVA induction of inflammation in human skin is thought to be mediated by membrane lipid derived products. In order to investigate the mechanism of this response we examined the effect of UVA on phospholipid metabolism of human epidermal keratinocytes in culture. Keratinocytes were grown in serum free low calcium medium. The cells were prelabeled with [3H] arachidonic acid or [3H] choline and irradiated with UVA (Honle 2002-Hg vapor lamp). Identification and quantitation of specific membrane phospholipid-derived components was achieved using high-performance liquid chromatography, paper chromatography, and radioimmunoassay. UVA resulted in a linear dose dependent release of [3H] arachidonic acid into medium between 1 and 20 joule/cm2. This response was inhibited in an oxygen-reduced environment. The radiolabel released was predominantly free arachidonate and cyclooxygenase metabolites. Cyclooxygenase metabolites prostaglandin E2 and prostacyclin derivative, 6-keto-prostaglandin F1a, were stimulated following UVA irradiation, but the lipoxygenase metabolite, leukotriene B was not detected. Maximal release was measured immediately after irradiation and changed little over 24 h post-irradiation. UVA stimulated an increase of [3H] choline metabolites glycerophosphorylcholine and phosphorylcholine in media extracts suggesting UVA activation of phospholipase C and phospholipase A2 or diacylglyceride lipase.

Arachidonic Acid↗
PubMed1990

Self-injury in psychiatric in-patients.

Suicide and self-injury in-patients were identified on the basis of a retrospective content analysis of special incidence reports completed the preceding year at an urban state psychiatric hospital. Select clinical and biodemographic variables were then examined, and in order to determine the importance of these variables in the prediction of incident severity, a multiple regression analysis was performed. Schizophrenic patients were found to be significantly over-represented among both the self-injury and suicide patients.

California↗
PubMed1988

Apnea-onset definition significantly affects pneumogram results.

Pneumogram (PG) scoring methods have not been standardized. To determine the extent to which varying definitions for apnea-onset and apnea-termination will result in clinically significant differences in calculated apnea density (A6/D%) and periodic breathing, we analyzed 40 randomly selected PGs. All PGs were initially scored using end-expiration (EE) to mark the beginning of each apnea. As the second definition, peak inspiration (PI) was used to identify the onset of each apnea. All apneas greater than or equal to 6 s in duration and all episodes of periodic breathing were identified. The differences between results obtained by each definition were compared by paired t-test. The differences between the EE and PI definitions were statistically significant (p less than 0.01) for A6/D%, periodic breathing, longest apnea, and number of apneas greater than 11 s, with the PI definition consistently resulting in higher values. In summary, calculated PG results are significantly different, both clinically and statistically, depending on the scoring definition utilized for apnea-onset. Although each definition will yield results that are internally consistent, it is crucial that the normative standards used for comparison be derived utilizing the same scoring definition.

Cardiography, Impedance↗
PubMed1988

Ultraviolet radiation alters choline phospholipid metabolism in human keratinocytes.

Ultraviolet radiation B (UVB-290-320 nm) induces inflammation and hyperproliferation in human epidermis. This response is associated with the recovery from irradiated skin of inflammatory mediators derived from membrane phospholipids. We have previously reported that UVB stimulates the production of such mediators by human keratinocytes (HK) in culture. In these studies we examined the effect of UVB on the metabolism of choline containing phospholipids in HK prelabeled with [3H] choline. UVB (400-1600J/m2) stimulated a dose dependent release of [3H] choline from HK within minutes of irradiation. Examination of media extracts by paper chromatography revealed that the released [3H] choline was predominately in the form of glycerophosphorylcholine. Examination of label remaining in membranes of cells after irradiation by acid precipitation and HPLC revealed that the origin of the released [3H] choline was the membrane phosphatidylcholine/lysophosphatidylcholine. These data support a concept of UVB stimulation of both a phospholipase A (1 or 2) and a lysophospholipase. These UVB induced alterations of HK membrane phospholipid metabolism likely have profound effects on UVB-induced inflammation and control of cell growth in human skin.

Cells, Cultured↗