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Biomedical subjects

R Brand

Publications and source records attributed to R Brand.

At least 37 records · Page 2Linked to original sources

Randomised clinical trial on the effect of the Dutch obstetric peer review system.

The project "Obstetric Peer Review Interventions" (Verloskundige Onderlinge Kwaliteitsspiegeling Interventies, VOKSINT) was set-up in The Netherlands in 1994. It provided annual comparison data (quality ranking, league tables) for secondary care obstetric departments adjusted for population differences, based on the data registered in the Perinatal Database of The Netherlands (Landelijke Verloskunde Registratie, LVR). The aim of the so-called VOKS reports was to influence obstetricians' interventions in such a way that they led to a more homogeneous policy. To assess this influence, a trial was set-up, with departments randomly assigned to be or not to be informed about the VOKS results. Obstetric intervention rates and the morbidity of newborns including neonatal neurological examinations (NNEs) were assessed. Obstetric intervention rates were similar in the report group and the control group. Practice in the report group became more homogeneous (adjusted for population differences) than in the control departments, but this was only statistically significant for term caesarean section.

Cesarean Section↗

Fibroblast orientation to stretch begins within three hours.

Most connective tissue cells align in response to stretch. Previous studies have shown these responses occur within 12-14 h of initiation of stretch, but do not identify the time at which this orientation occurs, nor whether the orientation continues after cessation of stretch. To ascertain the earliest times at which fibroblast orientation occurs, we cultured primary human fibroblasts on deformable culture dishes and stretched (1 Hz, 8% uniaxial strain) them for up to 24 h. We photographed the cells at 0.5, 1-6, 8, 10, 12, 14, 16, and 24 h. Similarly cells were photographed at 1-3, or 4 h after cessation of stretch for stretch durations of 1, 2, and 3 h. Orientation of cells were ascertained by an interactive computer program. The fibroblasts began to orient by 2-3 h and orientation appeared nearly complete by 24 h. Cultures stretched for 2 or 3 h continued to exhibit greater degrees of orientation (compared to controls) for 2 or 3 h respectively after cessation of stretch. We conclude fibroblasts begin to orient within 3 h of initiation of stretch, and that they continue to orient for several hours after cessation of stretch.

Adaptation, Physiological↗

Clinical characteristics of Chlamydia trachomatis infections in a general outpatient department of obstetrics and gynaecology in the Netherlands.

OBJECTIVE: Evaluation of prevalence and risk factors of Chlamydia trachomatis infections in an outpatient obstetric and gynaecological population. METHODS: A prospective, observational study was performed at an inner city hospital in The Hague, Netherlands. 1368 women attending the outpatient department of obstetrics and gynaecology participated in the study. For detection of C trachomatis infections we used amplification of CT rRNA in urine samples (Gen Probe/AMPLIFIED-CT) and DNA probe for detection of CT rRNA from a urethral, endocervical and anal swab (Gen Probe/PACE 2). RESULTS: The overall prevalence of C trachomatis infections in our general obstetric and gynaecological population was 4.5%. The prevalence in women under 30 years of age was 8. 1%. We found age and postcoital bleeding to be significant risk factors. We did not find significant differences between women from different ethnic origin or between women using different kinds of contraceptives. 12 (19.4%) patients with C trachomatis infections were found positive by urine test only, and 15 (24.2%) only by DNA probe. CONCLUSIONS: Age is the most important risk factor in our population (overall prevalence 4.5%, prevalence in women under 20 years of age 15.8%). Analyses of urine and of endocervical specimens are complementary for the determination of the prevalence of C trachomatis infections in women. Cost effectiveness analysis is needed to determine to what extent age based screening and/or antibiotic prophylaxis before intrauterine manipulations is indicated.

Adult↗

Substandard care in immigrant versus indigenous maternal deaths in The Netherlands.

As part of the Confidential Enquiry into the Causes of Maternal Deaths in The Netherlands, substandard care was assessed in immigrant versus indigenous maternal deaths. Except for substandard care related to the women's and relatives' decisions, substandard care factors were hypothesised to occur in similar frequency among both groups of women. The results, however, indicate that substandard care factors related to all aspects of care were disproportionately more frequent in immigrant women. More research into the interpretation of these worrying data is needed.

Emigration and Immigration↗

Alternating hepatic arterial infusion and systemic chemotherapy for liver metastases from colorectal cancer: a phase II trial using intermittent percutaneous hepatic arterial access.

PURPOSE: To evaluate the objective response to a short course of hepatic arterial infusion (HAI) using temporary, percutaneously placed catheters alternating with systemic prolonged continuous infusion fluorouracil (ci 5-FU) and daily oral leucovorin (L). PATIENTS AND METHODS: Eligible patients were previously untreated (except for adjuvant therapy) adults with liver-predominant metastases, with Eastern Cooperative Oncology Group performance status of 0 to 2. Treatment regimen included HAI with fluorodeoxyuridine (FUDR) 60 mg/m2/d and L 15 mg/m2/d continuously infused daily for 4 days. After a 1-week rest, ci 5-FU was administered through a central venous access device using a dose of 180 mg/m2/d with a fixed dose of oral L at 5 mg/m2/d for 21 out of 28 days. Cycles were repeated every 6 weeks. After four cycles of therapy, patients were maintained on ci 5-FU and daily oral L until evidence of progression. RESULTS: Forty-three patients were enrolled onto this trial. One patient was ineligible. The objective response rate for all patients (17 partial, zero complete) was 41% (95% confidence interval [CI], 26% to 56%). Five patients were not able to receive at least one complete cycle of HAI. Among patients who received at least one complete cycle of HAI, the response rate was 46% (95% CI, 30% to 62%). Five patients underwent a liver resection after enrolling onto the protocol. At the time of analysis, estimated median time to progression was 6 months, and estimated median overall survival was 13 months. CONCLUSION: The objective response rate was comparable to that achieved with more prolonged and more frequent HAI using FUDR. This approach should be studied as an acceptable alternative to surgically placed hepatic arterial catheters/pumps and may have a role as neoadjuvant therapy for liver metastases that are unresectable, as well as an adjuvant role for patients with resected hepatic metastatic colorectal cancer.

Adult↗

A three-dimensional regression model of the shoulder rhythm.

OBJECTIVE: The development of a thorax-fixed regression model for the shoulder which statistically predicts the orientation of the clavicle and the scapula from the humerus orientation. BACKGROUND: The application of three-dimensional position recording systems to the shoulder mechanism is limited to laboratory conditions. Studies in the field of ergonomics and sports require a method that can be applied in situ. It was found that the relation between the scapular and the humeral motions is consistent. In order to facilitate the biomechanical research on the shoulder a descriptive statistical model of the shoulder rhythm was developed. METHODS: The orientation of the shoulder bones of 10 subjects was determined in a large range of 23 humerus positions. The elbow was flexed in a splint and the arm was fully supported. The subjects exerted a 20 N external abduction and adduction force at the elbow in a plane perpendicular to the humerus. Other forces and moments were mechanically minimized. During the task the postures of the shoulder were recorded. The linear regression equations for the clavicular and scapular orientations were determined by means of a repeated measurements multi-variate analysis of variance for the co-variates: humerus orientation, initial orientation of the clavicle and the scapula, external force direction, gender and morphological characteristics of the subjects. RESULTS: The orientation of the clavicle and the scapula was predicted by five linear regression equations, including the co-variates: humerus orientation, external force direction and initial position. Morphology and gender did not significantly contribute to the clavicular and scapular orientation predictions. CONCLUSIONS: A statistical model is developed for the prediction of clavicular and scapular orientations, based on the humerus position, the initial posture and the direction of the external force. The model fitted well on an independent set of recorded position data for a different group of subjects. RELEVANCE: Morphological data of the shoulder girdle and gender did not significantly contribute to the model structure.

Biomechanical Phenomena↗

The Perinatal Database of the Netherlands.

OBJECTIVE: In the Netherlands, the Perinatal Database of the Netherlands (Landelijke Verloskunderegistratie, LVR) was set up in 1982 for secondary care obstetric departments on a voluntary participation basis, its main goal being quality monitoring. At the outset of the database, 70% of Dutch obstetric departments participated immediately. This percentage has now increased to almost 100%. How the LVR was set up, its aims, participation, general function and some aspects of the reliability are described in this article. RESULTS: Assessment of the reliability of the data on a number of points found that the frequency of various types of nearly all errors has decreased during the existence of the LVR, with the exception of a complete registration of the first-week mortality. CONCLUSIONS: The quality of the data has improved over the years. More reliable figures for the first-week mortality would be available if the LVR data were linked to those of the Neonatal Database of the Netherlands (Landelijk Neonatale Registratie, LNR), so that the condition of each child is known up to and including 28 days after birth. Improvements in the reliability of other items can be attained by implementing more checks during the data input stage and by making the data more accessible to the gynaecologists, in order to further increase motivation to record the data.

Cesarean Section↗

Early cell adhesion events differ between osteoporotic and non-osteoporotic osteoblasts.

In osteoporosis, the regenerative capacity of bone is compromised, which may involve altered osteoblast (OB) activity. This could be attributed to an inappropriate synthesis and assembly of an extracellular matrix (ECM), altered cell adhesion to the ECM, or be due to inappropriate downstream activation of adhesion-mediated signaling cascades through proteins such as focal adhesion kinase (FAK). The purpose of our study was to compare early adhesion-mediated events using previously described and characterized clinically derived OBs obtained from human patients undergoing major joint arthroplasty for osteoporosis or osteoarthritis. The presence or absence of osteoporosis was established with a radiographic index. Using light microscopy and crystal violet staining, we show that OB cells derived from sites of osteoporosis do not attach and spread as well as non-osteoporotic (OP) OB cells. OP cells initially have a more rounded morphology, and show significantly less (P < 0.001) attachment to serum-coated tissue culture plastic over a 24 h time period. Immunofluorescent labeling after 24 h of attachment showed that OP OB focal adhesions (FAs) and stress fibers were less defined, and that the OP cells were smaller and had a more motile phenotype. When normalized protein lysates were Western blotted for phosphotyrosine (PY) a band corresponding to pp125FAK was identified. FAK tyrosine phosphorylation was evident at 6 h in both the OP and non-OP OBs, but decreased or was absent through 24 h in OP OBs. These results suggest early adhesion-mediated events, such as cell adhesion, attachment, and FAK signaling via PY may be altered in OP OBs.

Actins↗

Modulation of calcium oxalate monohydrate crystallization kinetics by urine of preterm neonates.

Preterm neonates frequently develop nephrocalcinosis (NC). However, the cause has not yet been elucidated. This study focuses on the effects of urine from preterm neonates on crystallization kinetics. Urine samples were collected and renal ultrasound examinations of preterm neonates (gestational age < 32 weeks) were performed during the first weeks of life, at term, and ages 6, 12, and 24 months. The effect of urine on crystallization was determined using a seeded crystal growth system, which measures the square root of solubility product ( radicalLc), percentage of growth inhibition (GI), and agglomeration inhibition ([tm]) of calcium oxalate crystals. Data for preterm neonates in the first weeks of life (n = 19) were compared with those for full-term neonates (n = 17) and healthy adults. Moreover, the correlation between [tm] and urinary (U)citrate level was studied. Mean radicalLc (0.27 +/- 0.1 versus 0.36 +/- 0.08 mmol/L) and mean [tm] (81 +/- 32 versus 143 +/- 97 minutes) were lower and mean Ucalcium-creatinine (2.20 +/- 1.74 versus 0.46 +/- 0.73 mol/mol) and Uoxalate-creatinine ratios (0.39 +/- 0.21 versus 0.16 +/- 0.09 mol/mol) were greater in preterm neonates in the first weeks of life compared with full-term neonates (p < 0.05). Furthermore, [tm] was less than the lower limit for healthy adults for all but one preterm neonate; [tm] increased and Ucalcium-creatinine and Uoxalate-creatinine ratios decreased with age (p < 0.005). There was a correlation between [tm] and citrate excretion (coefficient of 38; P < 0.001). Patients with and without NC at term did not differ statistically in mean radicalLc, percentage of GI, or [tm]. In conclusion, urine from preterm neonates in the first weeks of life is highly supersaturated and has a defective ability to inhibit calcium oxalate crystal agglomeration. This ability improves with age and is citrate mediated. We suggest that both the high level of supersaturation and defective ability to inhibit calcium oxalate crystal agglomeration contribute to the high incidence of NC.

Adult↗

Gender differences in colorectal polyps and tumors.

OBJECTIVES: To use a national endoscopy database (CORI) to determine 1) whether gender differences are noted in the prevalence and location of polyps and tumors; 2) whether women have a higher rate of right-sided polyps or tumors; and 3) whether age influences these results. METHODS: CORI database from April 1, 1997 to February 19, 1999, captured in a computer-generated report, was analyzed. Polyps for this study were defined as sessile or pedunculated and as >9 mm. Tumors were defined as lesions characteristic of adenocarcinoma (mass, apple-core). Pure right-sided colon (PRS) was defined as cecum, ascending, hepatic flexure; right-sided as PRS plus the transverse colon; and left-sided as the splenic flexure, descending, sigmoid and rectum. RESULTS: Men have a greater risk of polyps [odds ratio (OR), 1.5] and tumors (OR, 1.4) than women. The risk of finding polyps and tumors at colonoscopy increases with age, with the highest risk noted in those >69 yr of age relative to patients <50 yr of age (polyps, OR = 2.7; tumors, OR = 4.0). Right-side polyps and pure right-sided polyps as defined by the study design were noted to be more frequent than left-sided polyps in patients >60 yr of age. Women have a greater risk of developing pure right-sided polyps (OR, 1.2), tumors (OR, 1.6) and right-sided tumors (OR, 1.5) than men. CONCLUSIONS: Men have a higher prevalence of colon polyps and tumors than women. A progressive risk of polyp or tumor formation is noted with aging. Women had a greater number of pure right-sided polyps and tumor development. Colonoscopy is needed to correctly diagnose an increasing prevalence of right-sided pathology in the elderly.

Adenocarcinoma↗

[Quality of outcome in treating patients with chronic headache within a hospital specialized for migraine. A cohort study with one-year follow-up].

AIMS: To describe characteristics of in-patients with chronic headache syndromes being treated with complementary methods, short-term effects at time of discharge as well as long-term effects covering a catamnesis of 1 year. METHODS: The study was designed as a prospective cohort study with outcome measurements 2 months in advance of admission to the hospital, at admission, and at time of discharge, continued by follow-up queries 2, 6 and 12 months after discharge from the hospital. The parameters for describing the course of headache symptoms were registered by questionnaires and diaries. During the first 6 months in 1996, a total of 424 consecutive patients with migraine or tension-type headache at the 'Migräne-Klinik Königstein' were included. RESULTS: 82.9% of the patients were women, the mean age was 46.3 +/-13.0 years. The median of the duration of the disease was 23 years. At discharge from the hospital there was a marked improvement regarding frequency of headache attacks, intensity of headaches, and concomitant symptoms. 60.5% of the patients were classified as 'responders'. 67.5% responded to follow-up questionnaires. With exception of the duration of headache attacks, a significant improvement regarding the 6-month follow- up compared to base level was observed. Intake of drugs could be diminished and quality of life was improved. Patients suffering from tension-type headache showed smaller effects in general. CONCLUSIONS: Taking into account the mean duration of disease of more than 20 years the results suggest a clinically relevant success from the patients' view regarding the short-term as well as the long-term course. The problem of data loss with follow-up queries and missing comparative data reduce the conclusiveness of the results.

Adult↗

Comparative responsiveness of four elbow scoring instruments in patients with rheumatoid arthritis.

OBJECTIVE: This prospective study investigated the comparative responsiveness to change of 4 different elbow scoring instruments: 2 Hospital for Special Surgery elbow assessment scales, the Mayo Clinic Elbow Performance Index, and the Elbow Functional Assessment (EFA) Scale. METHODS: A group of patients with rheumatoid arthritis (RA) (median age 60 yrs) undergoing either elbow arthroplasty (22 elbows) or synovectomy with radial head excision (3 elbows) were evaluated both before and after surgery (median 7 mo postoperatively). Changes in the scores obtained using the scales under study were calculated and analyzed. The patient's opinion of global perceived effect of the intervention was used as an external criterion to classify them as "improved" or "non-changed." Responsiveness was evaluated with 3 different statistical approaches: using paired t statistics (pre and postsurgery scores), effect size statistics (standardized response mean, effect size, and responsiveness ratios), and receiver operator characteristic curves. Minimal clinically important difference was estimated using patient satisfaction as the external criterion. RESULTS: Each of the elbow rating measures under study proved to be responsive to change when evaluating patients with RA undergoing elbow arthroplasty or synovectomy. The EFA scale had the highest power to detect a clinically meaningful difference and had the best discriminative ability to distinguish improved from no-change patients, as shown by all responsiveness statistics applied. CONCLUSION: Using the EFA scale requires smaller sample sizes to achieve a fixed level of statistical power than the other scales we studied.

Adult↗

Excess wing in the dielectric loss of glass formers: A johari-goldstein beta relaxation?

Dielectric loss spectra of glass-forming propylene carbonate and glycerol at temperatures above and below T(g) are presented. By performing aging experiments lasting up to five weeks, equilibrium spectra below T(g) have been obtained. During aging, the excess wing, showing up as a second power law at high frequencies, develops into a shoulder. The results strongly suggest that the excess wing, observed in a variety of glass formers, is the high-frequency flank of a beta relaxation.

Journal Article↗

Selective referral to high-volume hospitals: estimating potentially avoidable deaths.

CONTEXT: Evidence exists that high-volume hospitals (HVHs) have lower mortality rates than low-volume hospitals (LVHs) for certain conditions. However, few employers, health plans, or government programs have attempted to increase the number of patients referred to HVHs. OBJECTIVES: To determine the difference in hospital mortality between HVHs and LVHs for conditions for which good quality data exist and to estimate how many deaths potentially would be avoided in California by referral to HVHs. DESIGN, SETTING, AND PATIENTS: Literature in MEDLINE, Current Contents, and First-Search Social Abstracts databases from January 1, 1983, to December 31, 1998, was searched using the key words hospital, outcome, mortality, volume, risk, and quality. The highest-quality study assessing the mortality-volume relationship for each given condition was identified and used to calculate odds ratios (ORs) for in-hospital mortality for LVHs vs HVHs. These ORs were then applied to the 1997 California database of hospital discharges maintained by the California Office of Statewide Health Planning and Development to estimate potentially avoidable deaths. MAIN OUTCOME MEASURES: Deaths that potentially could be avoided if patients with conditions for which a mortality-volume relationship had been treated at an HVH vs LVH. RESULTS: The articles identified in the literature search were grouped by condition, and predetermined criteria were applied to choose the best article for each condition. Mortality was significantly lower at HVHs for elective abdominal aortic aneurysm repair, carotid endarterectomy, lower extremity arterial bypass surgery, coronary artery bypass surgery, coronary angioplasty, heart transplantation, pediatric cardiac surgery, pancreatic cancer surgery, esophageal cancer surgery, cerebral aneurysm surgery, and treatment of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). A total of 58,306 of 121,609 patients with these conditions were admitted to LVHs in California in 1997. After applying the calculated ORs to these patient populations, we estimated that 602 deaths (95% confidence interval, 304-830) at LVHs could be attributed to their low volume. Additional analyses were performed to take into account emergent admissions and distance traveled, but the impact of loss of continuity of care for some patients and reduction in the availability of specialists for patients remaining at LVHs could not be assessed. CONCLUSIONS: Initiatives to facilitate referral of patients to HVHs have the potential to reduce overall hospital mortality in California for the conditions identified. Additional study is needed to determine the extent to which selective referral is feasible and to examine the potential consequences of such initiatives.

California↗

Treatment of acquired severe aplastic anemia: bone marrow transplantation compared with immunosuppressive therapy--The European Group for Blood and Marrow Transplantation experience.

Patients with severe aplastic anemia (SAA) can be successfully treated with bone marrow transplantation (BMT) or immunosuppressive therapy (IS). The current outcome using both forms of therapy among 3,669 patients treated in Europe between 1976 and 1998 is reviewed. Significant progress has been made and the overall risk of failure is now low, with survival rates greater than 80% for both treatments. Chronic graft-versus-host disease (GvHD) remains a problem for BMT patients, and carries a high risk of lethal complications. On the other hand, IS patients are exposed to late failure due to relapse or clonal/malignant diseases. First-line BMT from identical siblings is compared with IS therapy in an intent-to-treat analysis of 1,765 patients, regardless of subsequent transplant status. The outcome of SAA patients has improved considerably over time and is influenced by patient variables such as severity of the disease and age, but also by the choice of the initial treatment.

Anemia, Aplastic↗

The Dutch 'Folic Acid Campaign'--have the goals been achieved?

Periconceptional folic acid use considerably reduces the risk of neural tube defects. The aim of this study was to measure the effect of the national and the local 'Folic Acid Campaign' on periconceptional folic acid use. Before (1995 survey) and 1 year after the campaign (1996 survey), the awareness and use of folic acid was measured among pregnant women in four regions of the Netherlands. To this end, pregnant women who visited the midwife, general practitioner or obstetrician for the first or second prenatal visit were asked to complete a questionnaire. The results showed that use of folic acid for any period around conception increased from 25.1% in 1995 to 53.5% in 1996. Appropriate use (4 weeks before until 8 weeks after conception) increased from 4.8% in 1995 to 21.0% in 1996. No additional effect of the local Folic Acid Campaign was found (adjusted odds ratio= 1.0; 95% confidence interval = 0.7, 1.4). It was possible to conclude that folic acid use at the recommended time increased considerably as a result of the national and the local Folic Acid Campaign, but the target (use in 46% of women wishing to conceive) was not achieved. New health education programmes are needed to increase further its use at the appropriate times.

Adolescent↗

Toxic epidermal necrolysis in Western Australia.

Toxic epidermal necrolysis is a severe, life-threatening illness with up to one-third mortality. We report a retrospective analysis of all cases treated in Royal Perth Hospital over a 20-year period from July 1978 to June 1998, by analysis of medical records. A total of 12 patients with an age range of 23-73 years was identified. The female to male ratio was 2:1, with age of onset earlier in females. All cases were associated with medications, most commonly antibiotics, anticonvulsants and allopurinol. The mortality rate was one-third (four deaths), mostly resulting from cardiorespiratory failure, renal failure and sepsis. Risk factors for death were advanced age and severe underlying disease, including diabetes, alcoholic liver disease sepsis and malignancy. Among the six patients treated with systemic corticosteroids there was only one death. Treatment with corticosteroids appeared to be beneficial, with such patients having both fewer complications and a lower mortality rate.

Adrenal Cortex Hormones↗