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R Andersen

Publications and source records attributed to R Andersen.

At least 37 records · Page 2Linked to original sources
PubMed2001

Towards a strategy for optimal vitamin D fortification (OPTIFORD).

The research project "Towards a Strategy for Optimal Vitamin D Fortification (OPTIFORD)" has received financial support from the 5th framework programme of the EC. Vitamin D deficiency is a serious health problem among large population groups in Europe. Subjects segregated from sun exposure for social or religious reasons, or because of disability are at risk for vitamin D deficiency. Vitamin D is essential for proper bone mineralisation and vitamin D deficiency is recognised to be an important risk factor for hip fracture. Fortification and/or supplementation strategies could be effective and inexpensive ways of arresting preventable health consequences. However, fortification policies in Europe differ and this reflects the many unknowns in relation to the strategy of vitamin D fortification of food, particularly concerning the levels achieving optimal effects without toxicity. The overall objective of OPTIFORD is to investigate if fortification of food with vitamin D is a feasible strategy to remedy the insufficient vitamin D status of large population groups in Europe, and to determine at what level fortification should be pitched. An important outcome is to reinforce the scientific basis for recommendations on vitamin D as a nutrient.

Bone Development↗
PubMed2000

Separation and determination of alditols and sugars by high-pH anion-exchange chromatography with pulsed amperometric detection.

Carbohydrates such as alditols (polyols or sugar alcohols), monosaccharides and disaccharides are separated as anions by anion-exchange chromatography with a sodium hydroxide eluent, MA1 CarboPac column and pulsed amperometric detection. We report a high-pH anion-exchange chromatographic-pulsed amperometric detection (HPAEC-PAD) method that determines all the polyols used as food additives in food products and the most commonly found mono- and disaccharides on a routine basis. The linearity, repeatability, internal reproducibility and accuracy are described. The applicability of the method has been demonstrated by the analysis of 46 relevant samples and by participation twice in the Food Analysis Performance Assessment Scheme (FAPAS) testing programme for food additives.

Anion Exchange Resins↗
PubMed2000

Laparoscopic lymphocelectomy: a multi-institutional analysis.

PURPOSE: Because symptomatic lymphoceles are infrequent, single center studies generally report small numbers of patients. We report a multi-institutional experience with and long-term outcome following laparoscopic lymphocelectomy in 81 patients. MATERIALS AND METHODS: Data were obtained from 9 institutions at which at least 5 cases of laparoscopic lymphocelectomy had been performed. Baseline patient demographics, operative time and blood loss, special operative adjunct techniques, postoperative course, convalescence, complications and lymphocele recurrence data were collected and analyzed. RESULTS: A total of 56 men and 25 women with a mean age of 41 years were included in the study. Lymphocele formed after renal transplantation in 78 patients (96%) and after pelvic lymph node dissection in 3 (4%). Average operating time was 123 minutes with a mean blood loss of 43 ml. Omentopexy was performed in 11 cases (13.6%). No intraoperative stenting of the transplant ureter was performed. Intraoperative complications consisted of laryngospasm, bladder injury, inferior epigastric artery injury and mild renal capsule hematoma in 1 patient each. Conversion to open surgery was required for repair of bladder injury in 1, repair of preexisting hernia in 1, unusually thickened lymphocele wall in 1 and inaccessible lymphocele location in 4 cases. Mean time to ambulation and resumption of regular diet was 1 day, and mean hospital stay was 1.5 days. Postoperative complications included trocar site hernia in 1 and urinary retention in 2. Convalescence averaged 2.5 weeks. During a mean followup of 27 months 5 patients (6%) had lymphocele recurrence. CONCLUSIONS: Laparoscopic lymphocelectomy is safe, minimally invasive and effective. It is an excellent alternative to the conventional open surgical approach.

Adult↗
PubMed2000

Violence victimization after HIV infection in a US probability sample of adult patients in primary care.

OBJECTIVES: This study estimated the proportion of HIV-infected adults who have been assaulted by a partner or someone important to them since their HIV diagnosis and the extent to which they reported HIV-seropositive status as a cause of the violence. METHODS: Study participants were from a nationally representative probability sample of 2864 HIV-infected adults who were receiving medical care and were enrolled in the HIV Costs and Service Utilization Study. All interviews (91% in person, 9% by telephone) were conducted with computer-assisted personal interviewing instruments. Interviews began in January 1996 and ended 15 months later. RESULTS: Overall, 20.5% of the women, 11.5% of the men who reported having sex with men, and 7.5% of the heterosexual men reported physical harm since diagnosis, of whom nearly half reported HIV-seropositive status as a cause of violent episodes. CONCLUSIONS: HIV-related care is an appropriate setting for routine assessment of violence. Programs to cross-train staff in antiviolence agencies and HIV care facilities need to be developed for men and women with HIV infection.

Adolescent↗
PubMed2000

Perceived unmet need for oral treatment among a national population of HIV-positive medical patients: social and clinical correlates.

OBJECTIVES: This study examines social, behavioral, and clinical correlates of perceived unmet need for oral health care for people with HIV infection. METHODS: Baseline in-person interviews with 2864 individuals were conducted with the HIV Cost and Services Utilization Study cohort, a nationally representative probability sample of HIV-infected persons in medical care. Bivariate and logistic regression analyses were conducted, with unmet need in the last 6 months as the dependent variable and demographic, social, behavioral, and disease characteristics as independent variables. RESULTS: We estimate that 19.3% of HIV-infected medical patients (n = 44,550) had a perceived unmet need for dental care in the last 6 months. The odds of having unmet dental needs were highest for those on Medicaid in states without dental benefits (odds ratio [OR] = 2.21), for others with no dental insurance (OR = 2.26), for those with incomes under $5000 (OR = 2.20), and for those with less than a high school education (OR = 1.83). Low CD4 count was not significant. CONCLUSIONS: Perceived unmet need was related more to social and economic factors than to stage of infection. An expansion of dental benefits for those on Medicaid might reduce unmet need for dental care.

Adult↗
PubMed2000

Protein kinase C epsilon mediates up-regulation of N-type calcium channels by ethanol.

Brief exposure to ethanol inhibits L-type and N-type voltage-gated calcium channels in neural cells. Although chronic ethanol exposure up-regulates the density and function of L-type channels via a protein kinase C (PKC) delta-dependent mechanism, the effect of prolonged ethanol exposure on N-type channels is not known. Using PC12 cells, we found that exposure to 25 to 150 mM ethanol for 0 to 8 days produced a time- and concentration-dependent increase in the density of binding sites for the N-type channel antagonist (125)I-omega-conotoxin GVIA. This was associated with an increase in omega-conotoxin GVIA-sensitive, depolarization-evoked rises in [Ca(2+)](i). Increases in (125)I-omega-conotoxin GVIA binding also were observed in the frontal cortex and the hippocampus, but not in the thalamus of mice exposed to ethanol vapor for 3 days. In PC12 cells, increases in (125)I-omega-conotoxin GVIA binding were blocked by the PKC inhibitor bisindolylmaleimide I and by expression of a selective peptide inhibitor of PKCepsilon. Expression of a selective inhibitor of PKCdelta did not alter ethanol-induced increases in (125)I-omega-conotoxin GVIA binding. These findings indicate that PKCepsilon mediates up-regulation of N-type channels by ethanol. Because N-type channels modulate calcium-dependent neurotransmitter release, these findings suggest a mechanism that may contribute to neuronal hyperexcitability observed during alcohol withdrawal.

Animals↗
PubMed2000

Access of vulnerable groups to antiretroviral therapy among persons in care for HIV disease in the United States. HCSUS Consortium. HIV Cost and Services Utilization Study.

OBJECTIVE: To employ the behavioral model of health services use in examining the extent to which predisposing, enabling, and need factors explain the treatment of the HIV-positive population in the United States with highly active antiretroviral therapy (HAART). DATA SOURCE: A national probability sample of 2,776 adults under treatment for human immunodeficiency virus (HIV) infection. STUDY DESIGN: The article uses data from the baseline and six-month follow-up surveys. The key independent variables describe vulnerable population groups including women, drug users, ethnic minorities, and the less educated. The dependent variable is whether or not a respondent received HAART by December 1996. DATA COLLECTION: All interviews were conducted using computer-assisted personal interview instruments designed for this study. Ninety-two percent of the baseline interviews were conducted in person and the remainder over the telephone. PRINCIPAL FINDINGS: A multistage logit regression shows that the predisposing factors that have previously described vulnerable groups in the general population with limited access to medical care also define HIV-positive groups who are less likely to gain early access to HAART including women, injection drug users, African Americans, and the least educated (odds ratios, controlling for need, ranged from 0.35 to 0.59). CONCLUSIONS: Those HIV-positive persons with the greatest need (defined by a low CD4 count) are most likely to have early access to HAART, which suggests equitable access. However, some predisposing and enabling variables continue to be important as well, suggesting inequitable access, especially for African Americans and lower-income groups. Policymakers and clinicians need to be sensitized to the continued problems of African Americans and other vulnerable populations in gaining access to such potentially beneficial therapies. Higher income, anonymous test sites, and same-day appointments are important enabling resources.

Adult↗
PubMed1998

[Early diagnosis of congenital hearing loss. Use of oto-acoustic emission tests in newborn infants with increased risk of hearing impairment].

With the use of today's screening programme children with congenital hearing losses (prevalence about 1/1,000) get their diagnosis unacceptably late (median age 28 months). Newer screening methods as oto-acoustic emissions and auditory brain stem responses have been in use, separately or as combined tests. The methods are used both as universal screening and as screening of selected children with increased risk of congenital hearing impairment. On the basis of ten risk factors for congenital hearing loss, we present our results from screening in the neonatal period. 283 out of 8,980 children (3.2%) born in Ostfold county over a period of three years have been examined with the use of oto-acoustic emissions. 16 children had pathological emission tests bilaterally on repeated testing and underwent further examination in the ear-nose-and-throat department. One of these children has turned out to have hearing loss.

Audiometry, Evoked Response↗
PubMed1998

A health priorities model: application to mammography screening.

This study describes and empirically tests a health priorities model. This model predicts underuse of regular mammography screening among adult women within the larger health context in which such decisions are made. The model incorporates women's comparative illness threats, comparative importance of health behaviors, and demographic variables. A telephone survey was conducted with a sample of women (N = 887) older than 50, in 40 rural communities in the state of Washington. Logistic regression analyses showed that women who perceived themselves at low risk for getting breast cancer and/or who perceived another disease (i.e. heart attack) as an equal or greater threat than breast cancer were less likely to be regular screeners of mammography. In addition, women who perceived other health behaviors as more important than regular mammography screening were less likely to be regular screeners than those women who perceived regular mammography screening as more important. Current or anticipated health problems were not related to screening behavior. The results are discussed in light of the practical, theoretical, and empirical implications.

Aged↗
PubMed1998

Understanding the context of healthcare utilization: assessing environmental and provider-related variables in the behavioral model of utilization.

OBJECTIVE: The behavioral model of utilization, developed by Andersen, Aday, and others, is one of the most frequently used frameworks for analyzing the factors that are associated with patient utilization of healthcare services. However, the use of the model for examining the context within which utilization occurs-the role of the environment and provider-related factors-has been largely neglected. OBJECTIVE: To conduct a systematic review and analysis to determine if studies of medical care utilization that have used the behavioral model during the last 20 years have included environmental and provider-related variables and the methods used to analyze these variables. We discuss barriers to the use of these contextual variables and potential solutions. DATA SOURCES: The Social Science Citation Index and Science Citation Index. We included all articles from 1975-1995 that cited any of three key articles on the behavioral model, that included all articles that were empirical analyses and studies of formal medical care utilization, and articles that specifically stated their use of the behavioral model (n = 139). STUDY DESIGN: Design was a systematic literature review. DATA ANALYSIS: We used a structured review process to code articles on whether they included contextual variables: (1) environmental variables (characteristics of the healthcare delivery system, external environment, and community-level enabling factors); and (2) provider-related variables (patient factors that may be influenced by providers and provider characteristics that interact with patient characteristics to influence utilization). We also examined the methods used in studies that included contextual variables. PRINCIPAL FINDINGS: Forty-five percent of the studies included environmental variables and 51 percent included provider-related variables. Few studies examined specific measures of the healthcare system or provider characteristics or used methods other than simple regression analysis with hierarchical entry of variables. Only 14 percent of studies analyzed the context of healthcare by including both environmental and provider-related variables as well as using relevant methods. CONCLUSIONS: By assessing whether and how contextual variables are used, we are able to highlight the contributions made by studies using these approaches, to identify variables and methods that have been relatively underused, and to suggest solutions to barriers in using contextual variables.

Environment↗
PubMed1997

[Long-term prognosis in febrile convulsions with and without prophylaxis].

This is a long-term follow-up of occurrence of epilepsy, neurological, motor, intellectual, cognitive, and scholastic achievements in a cohort of children with febrile convulsions (n = 289), randomized in early childhood to either intermittent prophylaxis (diazepam at fever) or no prophylaxis (diazepam at seizures). At follow-up the two groups were of almost identical age (14.0 vs. 14.1 years), body weight (58.2 vs. 57.2 kg), height (168.2 vs. 167.7 cm) and head circumference (55.9 vs. 56.2 cm). The neurological examination, fine and gross motor development on Stott motor test, intellectual performance on the Wechsler Intelligence Scale for Children verbal IQ (105 vs. 105), performance IQ (114 vs. 111) and full scale IQ (110 vs. 108). cognitive abilities on an neuropsychological test battery, including short and long term, auditory and visual memory, visuomotor tempo, computer reaction time, reading test, scholastic achievements and the occurrence of subsequent epilepsy were also very similar. Children with simple and complex febrile convulsions had the same benign outcome. The long term prognosis in terms of subsequent epilepsy, neurological, motor, intellectual, cognitive, and scholastic ability was not influenced by the type of treatment applied in early childhood. Preventing new febrile convulsions appears no better in the long run than abbreviating them.

Anticonvulsants↗
PubMed1997

[Serotypes of the human immunodeficiency virus type 1 in Madrid].

BACKGROUND: HIV-1 shows high genetic variability, mainly in the genomic region codifying the envelope proteins, which are the most immunogenic. This fact explains the high heterogeneity of antibodies against HIV-1 epitopes. Both genetic and serologic diversity has allowed to classify HIV-1 variants in several subtypes (genotypes and serotypes, respectively). The clinical and epidemiological significance of infection caused by each subtype remains to be clarified. PATIENTS AND METHODS: Serum samples from 154 HIV-seropositive individuals living in Madrid were studied. Serotyping was performed using 4 peptides belonging to the V3 env region. Epidemiological and clinical variables examined in these patients were the route of infection, the year in which HIV infection occurred, the country of birth, and the rate of disease progression (rapid versus slow). RESULTS: 148 (96.2%) samples could be serotyped, and the B class was recognized in 131 (88.5%) of them. Serotype A/C was found in 9 (6.1%). Two samples (1.3%) reacted to peptide E; however, both were also reactive against the B peptide, suggesting co-infection with B and E subtypes. Six samples were EIA-reactive for HIV-1/2 but were typed as HIV-2 alone. Infection with serotypes A/C was more frequent amongst immigrants, mainly in Africans. There was not association between any subtype and the route of infection neither a different rate of disease progression. CONCLUSION: HIV-1 serotype B is the most frequently found in HIV-seropositive individuals living in Madrid, without association with the route of infection or the clinical course of the disease. Serotypes A/C and E were found sporadically, mainly among immigrants.

Africa↗
PubMed1996

The chicken beta 2-microglobulin gene is located on a non-major histocompatibility complex microchromosome: a small, G+C-rich gene with X and Y boxes in the promoter.

beta 2-Microglobulin is an essential subunit of major histocompatibility complex (Mhc) class I molecules, which present antigenic peptides to T lymphocytes. We sequenced a number of cDNAs and two genomic clones corresponding to chicken beta 2-microglobulin. The chicken beta 2-microglobulin gene has a similar genomic organization but smaller introns and higher G+C content than mammalian beta 2-microglobulin genes. The promoter region is particularly G+C-rich and contains, in addition to interferon regulatory elements, potential S/W, X, and Y boxes that were originally described for mammalian class II but not class I alpha or beta 2-microglobulin genes. There is a single chicken beta 2-microglobulin gene that has little polymorphism in the coding region. Restriction fragment length polymorphisms from Mhc homozygous lines, Mhc congenic lines, and backcross families, as well as in situ hybridization, show that the beta 2-microglobulin gene is located on a microchromosome different from the one that contains the chicken Mhc. We propose that the structural similarities between the beta 2-microglobulin and Mhc genes in the chicken are due to their presence on microchromosomes and suggest that these features and the microchromosomes appeared by deletion of DNA in the lineage leading to the birds.

Amino Acid Sequence↗
PubMed1996

Long term outcome of prophylaxis for febrile convulsions.

A cohort of 289 children with febrile convulsions who had been randomised in early childhood to either intermittent prophylaxis (diazepam at fever) or no prophylaxis (diazepam at seizures) was followed up 12 years later. The study focused on the occurrence of epilepsy and on neurological, motor, intellectual, cognitive, and scholastic achievements in the cohort. At follow up the two groups were of almost identical age (14.0 v 14.1 years), body weight (58.2 v 57.2 kg), height (168.2 v 167.7 cm), and head circumference (55.9 v 56.2 cm). The occurrence of epilepsy (0.7% v 0.8%), neurological examination, fine and gross motor development on the Stott motor test, intellectual performance on the Wechsler intelligence scale for children verbal IQ (105 v 105), performance IQ (114 v 111), and full scale IQ (110 v 108), cognitive abilities on a neuropsychological test battery, including short and long term, auditory and visual memory, visuomotor tempo, computer reaction time, reading test, and scholastic achievement were also very similar. Children with simple and complex febrile convulsions had the same benign outcome. The long term prognosis in terms of subsequent epilepsy, neurological, motor, intellectual, cognitive, and scholastic ability was not influenced by the type of treatment applied in early childhood. Preventing new febrile convulsions appears no better in the long run than abbreviating them.

Adolescent↗