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D Anderson

Publications and source records attributed to D Anderson.

At least 73 records · Page 4Linked to original sources
PubMed2000

The impact of the ovulatory cycle on cytokine production: evaluation of systemic, cervicovaginal, and salivary compartments.

To understand the impact of the menstrual cycle on immunologic parameters, we measured the level of cytokines and chemokines from plasma, cervicovaginal lavage (CVL), and saliva samples of 6 premenopausal women during the follicular and luteal phases of the ovulatory cycle. We demonstrate that the level of plasma interleukin-8 (IL-8) was 4-fold higher during the follicular phase than the luteal phase (p = 0.004), whereas plasma IL-1beta, IL-4, IL-6, IL-10, interferon-gamma (IFN-gamma), transforming growth factor-beta (TGF-beta), tumor necrosis factor-alpha (TNF-alpha), macrophage inflammatory protein-1alpha (MIP-1alpha), and TNF receptor II (TNFR II) were not altered during the ovulatory cycle. In the vaginal compartment, as measured from CVL samples, the levels of IL-6 and IL-1beta were both 5-fold higher in the follicular than the luteal phase (p = 0.0002 and 0.03, respectively). Salivary cytokine and chemokine samples were similar when measured during the luteal and the follicular phases. Additional analysis of lymphocyte subsets for phenotypic and functional markers indicated that they were not influenced by the ovulatory cycle. Collectively, these data suggest that IL-6, IL-8, and IL-1beta are differentially regulated during the ovulatory cycle.

Adolescent↗
PubMed2000

Healthcare provider characteristics and perceived confidence from HIV/AIDS education.

This study reports findings from six training projects designed to keep health providers up-to-date on emerging developments and approaches in HIV/AIDS care. Participants were 3,779 individuals who described themselves, their professional background, and their specific experience in the HIV/AIDS field. These characteristics were compared with their self-reported confidence in managing clients, counseling clients, providing services, and the training topics. A repeated-measures design examining level and change of confidence showed little support for links between provider characteristics and confidence due to HIV/AIDS training experience. Thus, knowing a provider's background does not necessarily provide diagnostic information about who might most benefit in improved confidence from HIV/AIDS educational training. These results suggest that HIV/AIDS training programs may be targeted broadly-to a wide range of healthcare providers of diverse backgrounds-with little or no impact on overall levels and changes in provider confidence.

Attitude of Health Personnel↗
PubMed2000

Hormonal levels among HIV-1-seropositive women compared with high-risk HIV-seronegative women during the menstrual cycle. Women's Health Study (WHS) 001 and WHS 001a Study Team.

There is a paucity of normative data on hormonal levels among HIV-infected women. Hormonal levels may influence fertility and HIV-related immunological and virological factors. The objective of this study was to determine progesterone and estradiol levels during the menstrual cycle in HIV-seropositive women compared with high-risk seronegative women. The study enrolled 55 HIV-infected and 10 high-risk uninfected women with self-reported regular menstrual cycles (25-30-day cycles). Progesterone and estradiol levels were determined on a weekly basis for 8 weeks. The analysis included evaluations from the first complete menstrual cycle for the 54 HIV-infected and 9 uninfected women who had at least one complete cycle. The median age was 35 years for HIV-infected women and 36 years for uninfected women. The median CD4+ count for HIV-seropositive women was 210 cells/mm3. The median menstrual cycle length was 28 days (range 22-49 days) for HIV-infected women and 25 days (range 24-44 days) for uninfected women. The maximum progesterone level during the luteal phase was normal (>3.0 ng/ml) for 52 (96%) of 54 HIV-seropositive women and 7 (78%) of 9 HIV-seronegative women (p = 0.09, Fisher's exact test). The median maximum progesterone level was 12.2 ng/ml in HIV-seropositive women and 7.2 ng/ml in HIV-seronegative women (p = 0.07, Wilcoxon test). The median maximum estradiol value during the follicular phase was 148 pg/ml for HIV-seropositive women and 111 pg/ml for HIV-seronegative women (p = 0.04, Wilcoxon test). Among HIV-infected women, there were no significant differences in progesterone and estradiol levels by antiretroviral therapy, baseline plasma viral load, or median CD4+ cell count. We conclude that HIV-infected women with self-reported normal menstrual cycles have normal levels of progesterone and estradiol during the menstrual cycle.

Adult↗
PubMed2000

Induced hypothermia during emergency department thoracotomy: an animal model.

BACKGROUND: Induced hypothermia is used clinically to prevent ischemic injury during elective procedures. We present an animal model of asanguinous hypothermic (10 degrees C) circulatory arrest, induced through a left anterior lateral thoracotomy after exsanguinating uncontrolled hemorrhage. METHODS: Through a left anterior thoracotomy, 26 swine (45-70 kg) sustained a laceration of the descending thoracic aorta, producing exsanguinating uncontrolled hemorrhage. After 5 minutes of severe hypotension (systolic BP <20 mm Hg), a 22 French Foley catheter was directed cephalad through the enlarged aortic wound. A solution (containing 42.5 mmol/L K+ and precooled to 1 degrees C) was infused to arrest/preserve the heart and brain. A second 24 French Foley catheter was then directed caudally through the same wound. The right atrium was opened to drain the venous system. The animal was cooled with a cardiopulmonary bypass pump (>5L/min) through the Foley catheters. Once 10 degree C was reached, a cannula was placed to the aortic root and the aortic laceration repaired. The animal was maintained at 10 degree C for a total of 90 minutes. Before the rewarming process, the circulation was rinsed with a solution containing normal levels of electrolytes followed by infusion of whole blood. Rewarming was performed by maintaining a 10-degree gradient on the heat exchanger. The first 16 animals were used in nonsurvival experiments to develop the technique and to record dural temperatures and electroencephalogram tracings. The last 10 animals were used to determine long-term survival and neurologic outcome. Group I: seven animals were kept at < 10 degrees C with flows less than 2L/min. Group II: three animals underwent 20, 30, and 40 minutes of no flow once they were cooled to 10 degrees C. After 6 weeks of survival and neurologic examinations, the brains were fixed for histologic evaluations. RESULTS: The average time to cool the head to 18 degrees C and 10 degrees C was 6 minutes and 12 minutes, respectively. The hematocrit fell below 2% by the end of the cooling period. A total of 7 of the 10 animals from the long-term study survived. Group I: five of seven animals survived. Four of the survivors had no appreciable neurologic deficits, were fully functional at 6 weeks, and had no evidence of histologic injury. One of the five survivors in this group had moderate neurologic disability. Of the two animals that died, one died from air embolism from the i.v. line. The second death was in an animal for which maximal cooling to 2.7 degrees C was attempted. Group II: The first two animals that had "no flow" for 20 and 30 minutes were fully functional and had normal neurologic examinations. However, the second animal was found to have brain injury on histologic examination. The last animal in this group died of accidental extubation during recovery. CONCLUSION: Induction of hypothermic arrest through the chest after exsanguination is possible. The further development of this technique may provide an extended state of "suspended animation" to allow for repairs of hemorrhaging injuries in trauma patients who require emergency department thoracotomy.

Animals↗
PubMed2000

Threshold of induced transparency in the relativistic interaction of an electromagnetic wave with overdense plasmas

An exact analytical investigation of the stationary solutions describing the interaction between high-intensity laser radiation and an overdense plasma is presented. Both the relativistic and striction nonlinearities are taken into account, and their joint action gives rise to a solitary solution. This solution clearly shows that there exists an inherent limit of the induced transparency on the density of the overdense plasma in order to obtain a stationary physical solution. Furthermore, it is found that the striction nonlinearity tends to create a strong peaking of the plasma electron density, which suppresses the laser penetration and significantly enhances the threshold intensity for induced transparency.

Journal Article↗
PubMed2000

Purification, crystallization and initial X-ray analysis of the head-tail connector of bacteriophage phi29.

The head-tail connector of bacteriophage phi29, an oligomer of gene product 10 (gp10), was crystallized into various forms. The most useful of these were an orthorhombic P22(1)2(1) form (unit-cell parameters a = 143.0, b = 157.0, c = 245.2 A), a monoclinic C2 form (a = 160.7, b = 143.6, c = 221.0 A, beta = 97.8 degrees ) and another monoclinic C2 form (a = 177.0, b = 169.1, c = 185.2 A, beta = 114.1 degrees ). Frozen crystals diffracted to about 3.2 A resolution. There is one connector per crystallographic asymmetric unit in each case. Rotation functions show the connector to be a dodecamer. Translation functions readily determined the position of the 12-fold axis in each unit cell. The structure is being determined by 12-fold electron-density averaging within each crystal and by averaging between the various crystal forms.

Bacillus Phages↗
PubMed2000

Intimate justice. III: Healing the anguish of abuse and embracing the anguish of accountability.

This article presents an exploratory approach to couples therapy for abuse based on intimate justice theory. The article explains "the accountability axiom," which brings the relationship between the anguish of abuse and the anguish of accountability into focus. Understanding the accountability axiom can help therapists simultaneously engage both the victim of abuse and the abuser by creating two therapeutic environments in conjoint therapy--one environment that affirms the victim and one that challenges the abuser. The ideas are based on a qualitative study conducted by the authors, and the approach is illustrated with a clinical case involving psychological abuse.

Adult↗
PubMed2000

Comparison of polyvinyl alcohol fixative with three less hazardous fixatives for detection and identification of intestinal parasites.

Polyvinyl alcohol (PVA) containing the fixative mercuric chloride is considered the "gold standard" for the fixation of ova and parasites in the preparation of permanently stained smears of stool specimens. However, mercuric chloride is potentially hazardous to laboratory personnel and presents disposal problems. We compared three new alternative, nontoxic fixatives with PVA, analyzing ease of sample preparation and quality of smears. Sixty-eight fresh stool specimens were divided into aliquots and placed in each of four different fixatives: PARASAFE (PS) (Scientific Devices Laboratory, Inc., Des Plaines, Ill.), ECOFIX (EC) (Meridian Diagnostics, Inc., Cincinnati, Ohio), Proto-Fix (PF) (Alpha-Tec Systems, Inc., Vancouver, Wash.), and low-viscosity PVA fixative (PVA) (Meridian). Specimens were processed and stained according to each manufacturer's directions. Parasites were found in 31 of 68 slide preparations with PVA, 31 with PF, 30 with EC, and 30 with PS. Blastocystis hominis and Iodamoeba bütschlii were preserved in a readily identifiable state by all methods of fixation. However, some parasites were more easily identified with some of the fixatives because of differences in parasite distortion. For example, Entamoeba histolytica (Entamoeba dispar) was detected in 13 stools fixed with PF, 7 with PVA, and 6 with EC but none with PS. Likewise, Chilomastix mesnili was identified in 13 specimens fixed with PF, 8 with EC, and 5 with PVA but only 1 with PS, while Entamoeba coli was seen much less frequently with PS than with the other three fixatives. A dirty background was observed in 41% of specimens prepared with PS, whereas background quality was acceptable with other fixatives. Sample preparation was most rapid with PS, although the EC method involved the fewest steps. In conclusion, PVA and PF produced the least parasite distortion, while PS proved unsatisfactory for the identification of E. histolytica, E. coli, and C. mesnili. Both PF and EC appear to be acceptable, environmentally safe substitutes for PVA.

Animals↗
PubMed2000

Osteoclasts expressing the measles virus nucleocapsid gene display a pagetic phenotype.

Osteoclasts (OCLs) in Paget's disease are markedly increased in number and size, have increased numbers of nuclei per multinucleated cell, and demonstrate increased resorption capacity and increased sensitivity to 1,25-(OH)(2)D(3), the active form of vitamin D. These cells also contain nuclear inclusions, reminiscent of those seen in paramyxovirus-infected cells, which cross-react with antibodies to measles virus nucleocapsid (MVNP) antigen. To elucidate the role of MV in the abnormal OCL phenotype of Paget's disease, we transduced normal OCL precursors with retroviral vectors expressing MVNP and the MV matrix (MVM) genes. The transduced cells were then cultured with 1,25-(OH)(2)D(3) for14 or 21 days to induce formation of OCL-like multinucleated cells. The MVNP-transduced cells formed increased numbers of multinucleated cells, which contained many more nuclei and had increased resorption capacity compared with multinucleated cells derived from empty vector-transduced (EV-transduced) and MVM-transduced or normal bone marrow cells. Furthermore, MVNP-transduced cells showed increased sensitivity to 1, 25-(OH)(2)D(3), and formed OCLs at concentrations of 1, 25-(OH)(2)D(3) that were 1 log lower than that required for normal, EV-transduced, or MVM-transduced cells. These results demonstrate that expression of the MVNP gene in normal OCL precursors stimulates OCL formation and induces OCLs that express a phenotype similar to that of pagetic OCLs. These results support a potential pathophysiologic role for MV infection in the abnormal OCL activity and morphology that are characteristic of pagetic OCLs.

Bone Marrow Cells↗
PubMed2000

Enhanced RANK ligand expression and responsivity of bone marrow cells in Paget's disease of bone.

Paget's disease is characterized by highly localized areas of increased osteoclast (OCL) activity. This suggests that the microenvironment in pagetic lesions is highly osteoclastogenic, or that OCL precursors in these lesions are hyperresponsive to osteoclastogenic factors (or both). To examine these possibilities, we compared RANK ligand (RANKL) mRNA expression in a marrow stromal cell line developed from a pagetic lesion (PSV10) with that in a normal stromal cell line (Saka), and expression in marrow samples from affected bones of Paget's patients with that in normal marrow. RANKL mRNA was increased in PSV10 cells and pagetic marrow compared with Saka cells and normal marrow, and was also increased in marrow from affected bones compared with uninvolved bones from Paget's patients. Furthermore, pagetic marrow cells formed OCLs at much lower RANKL concentrations than did normal marrow. Anti-IL-6 decreased the RANKL responsivity of pagetic marrow to normal levels, whereas addition of IL-6 to normal marrow enhanced RANKL responsivity. Thus, RANKL expression and responsivity is increased in pagetic lesions, in part mediated by IL-6. These data suggest that the combination of enhanced expression of RANKL in affected bones and increased RANKL sensitivity of pagetic OCL precursors may contribute to the elevated numbers of OCLs in Paget's disease.

Antibodies↗
PubMed2000

Trainee characteristics and perceptions of HIV/AIDS training quality.

HIV/AIDS education and training have played a vital role in keeping health providers up to date on emerging developments and approaches. This study reports findings from seven HIV/AIDS education and training projects. Participants in more than 600 training sessions described themselves, their professional background, and their general reasons for taking the training. Immediately following the training, they also rated the quality of their educational experience along several dimensions. Trainee characteristics were related to assessments of training quality, using a regression decision-tree analytic approach. Although effect sizes were generally small, quality ratings of the HIV/AIDS training experiences were associated with certain projects, basic trainee demographic characteristics, professional background, and experience in the HIV field. Greater understanding about participant characteristics can provide clues about how these training experiences are perceived and processed and may inform decision making about instructional HIV/AIDS curricula.

Adult↗
PubMed2000

Alcohol and drug abuse in sexual and nonsexual violent offenders.

According to a literature review by Marshall (1996), presently available data have not clarified the proportion of sexual offenders who would meet diagnostic criteria for addictive problems. Our own literature review failed to find published studies comparing sexual offenders to nonsexual violent offenders on standardized measures of substance abuse. Our study is a preliminary investigation of the differences between sexual offenders (rapists: n = 72; child molesters: n = 34) and nonsexual violent offenders (n = 24) on measures of alcohol and drug abuse. The findings indicate that sexual offenders were more likely to abuse alcohol than were nonsexual violent offenders. Nonsexual offenders were significantly more likely to have had a history of other forms of substance abuse. The results are considered in terms of theories of alcohol's contribution to aggressive behavior and sexual aggression. Implications for assessment and treatment of sexual offenders are discussed.

Adult↗
PubMed2000

Hes6 acts in a positive feedback loop with the neurogenins to promote neuronal differentiation.

During the development of the vertebrate nervous system, neurogenesis is promoted by proneural bHLH proteins such as the neurogenins, which act as potent transcriptional activators of neuronal differentiation genes. The pattern by which these proteins promote neuronal differentiation is thought to be governed by inhibitors, including a class of transcriptional repressors called the WRPW-bHLH proteins, which are similar to Drosophila proteins encoded by hairy and genes in the enhancer of split complex (E-(SPL)-C). Here, we describe the isolation and characterization of Hes6, which encodes a novel WRPW-bHLH protein expressed during neurogenesis in mouse and Xenopus embryos. We show that Hes6 expression follows that of neurogenins but precedes that of the neuronal differentiation genes. We provide several lines of evidence to show that Hes6 expression occurs in developing neurons and is induced by the proneural bHLH proteins but not by the Notch pathway. When ectopically expressed in Xenopus embryos, Hes6 promotes neurogenesis. The properties of Hes6 distinguish it from other members of the WRPW-bHLH family in vertebrates, and suggest that it acts in a positive-feedback loop with the proneural bHLH proteins to promote neuronal differentiation.

Amino Acid Sequence↗
PubMed2000

Effects of iron salts and haemosiderin from a thalassaemia patient on oxygen radical damage as measured in the comet assay.

Thalassaemia is a group of genetic diseases where haemoglobin synthesis is impaired. This chronic anaemia leads to increased dietary iron absorption, which develops into iron overload pathology. Treatment through regular transfusions increases oxygen capacity but also provides iron through the red cells' haemoglobin. An essential treatment, in parallel with transfusions, is the use of chelating agents to remove the excess iron deposited in tissues. These deposits are found in the liver, spleen, heart, and pancreas and are associated with cardiac failure and diabetes. The deposits in these tissues of patients have been isolated as haemosiderin. Thalassaemia patients are particularly at risk of free radical induced damage. Thus, the present study has investigated, as a model system, human cells in vitro in the Comet assay in the presence of free radicals. This assay measures DNA damage, particularly DNA strand breakage. The effects of iron overload on cells oxidatively stressed with hydrogen peroxide (H(2)O(2)) have been determined as well as the effect of the chelating agent, deferoxamine. Iron overload was simulated with ferric (FeCl(3)) and ferrous chloride (FeCl(2)), ferrous sulphate (FeSO(4)) and haemosiderins. Both human lymphocytes from a male and a female donor and human adenocarcinoma colonic cells showed an increase in DNA damage in the Comet assay after treatment with H(2)O(2). Ferric chloride produced an increase in DNA damage in human colonic cells, but little or no damage in human lymphocytes. Ferrous chloride also produced weak DNA damage in human lymphocytes, but ferrous sulphate produced a dose-related response. Deferoxamine produced no DNA damage. When H(2)O(2) was combined with FeCl(3), FeCl(2), or FeSO(4), the DNA damage produced was as least as great as or slightly greater than with H(2)O(2) alone. When deferoxamine was combined with H(2)O(2) and FeSO(4) there was a consistent decrease in response. There was little or no decrease in response when deferoxamine was combined with H(2)O(2) and FeCl(3) or FeCl(2), but at high (100-300microm) doses there were changes in the appearance of cellular DNA from Comet tails to dense centres surrounded by a diffuse area. This was probably as a consequence of chelation processes. Haemosiderin produced no damage. The three fractions of haemosiderin examined were of three different densities and from a Thai patient where the oxyhydroxide phase is the ferrihydrite. The colour change was similar to that for FeCl(3), but the level of the ferric ion in the haemosiderin was possibly too low in the sample to produce a response. The next stage is to examine peripheral lymphocytes from thalassaemic patients, with and without chelation therapy, whose cells may be more sensitive to simulated iron overload and to lower levels of haemosiderin. Teratogenesis Carcinog. Mutagen. 20:11-26, 2000.

Caco-2 Cells↗
PubMed2000

Outpatient treatment of pulmonary embolism with dalteparin.

BACKGROUND: Pulmonary embolism is a common complication of deep vein thrombosis. It has been established that low molecular weight heparin may be used to treat deep vein thrombosis or pulmonary embolism and randomized studies have established that outpatient management of deep vein thrombosis with low molecular weight heparin is at least as effective as in-hospital management with unfractionated heparin. METHODS: This was a prospective cohort study of eligible patients with pulmonary embolism managed as outpatients using dalteparin (200 U/kg s/c daily) for a minimum of five days and warfarin for 3 months. Outpatients included those managed exclusively out of hospital and those managed initially for 1-3 days as inpatients who then completed therapy out of hospital. Reasons for admission included hemodynamic instability; hypoxia requiring oxygen therapy; admission for another medical reason; severe pain requiring parenteral analgesia or high risk of major bleeding. Patients were followed for three months for clinically apparent recurrent venous thromboembolism and bleeding. RESULTS: Between three teaching hospitals, a total of 158 patients with pulmonary embolism were identified. Fifty patients were managed as inpatients and 108 as outpatients. Of the outpatients, 27 were managed for an average of 2.5 days as inpatients and then completed dalteparin therapy as outpatients. The remaining 81 patients were managed exclusively as outpatients with dalteparin. For all outpatients the overall symptomatic recurrence rate of venous thromboembolism was 5.6% (6/108) with only 1.9% (2/108) major bleeds. There were a total of four deaths with none due to pulmonary embolism or major bleed. CONCLUSIONS: This prospective study suggests that outpatient management of pulmonary embolism is feasible and safe for the majority of patients.

Adult↗
PubMed2000

Population of households in England to 2021.

This article outlines the methodology and results of the Department of the Environment, Transport and the Regions (DETR) 1996-based household projections for England, and its regions. It examines differences between this round of projections and the previous 1992-based round. The 1996-based projections indicate that between 1996 and 2021 a growth of 3.8 million households can be expected in England, if recent trends continue. Both the national and subnational methodology and results are covered.

Adolescent↗
PubMed2000

Risk factors for diethylstilbestrol-associated clear cell adenocarcinoma.

OBJECTIVE: To assess the influence of postnatal factors on the development of clear cell adenocarcinoma in women exposed to diethylstilbesterol (DES), particularly factors related to exogenous or endogenous hormone exposures, and to reassess the relation of season of birth. METHODS: For the analysis of postnatal factors, 244 cases were compared with 244 age-matched DES-exposed women. Information was obtained from telephone interviews, with questions asked in reference to an index age, the age at which clear cell adenocarcinoma was diagnosed. For the analysis of season of birth, 604 cases, living or deceased, were compared with 1749 DES-exposed women. RESULTS: Neither oral contraceptive (OC) use nor pregnancy was associated with risk of clear cell adenocarcinoma: the odds ratios (OR) were 1.1 (95% confidence interval [CI] 0.7, 1.8) for OC use and 1.3 (95% CI 0.7, 2.3) for pregnancy. The OR for fall season of birth relative to all other seasons was 1.2 (95% CI 0.9, 1.4). CONCLUSION: Pregnancy and OCs do not increase risk of DES-associated clear cell adenocarcinoma. In addition, season of birth does not appear to be a material factor; the previous finding of an increased risk for fall season of birth is most likely not valid and probably a chance finding due to small sample size.

Adenocarcinoma, Clear Cell↗