Biomedical subjects

R Brand

Publications and source records attributed to R Brand.

At least 91 records · Page 5Linked to original sources

PubMed1996

Hereditary cerebral hemorrhage with amyloidosis-Dutch type: better correlation of cognitive deterioration with advancing age than with number of focal lesions or white matter hyperintensities.

The relationship between cognitive deterioration and abnormalities detected by magnetic resonance imaging (MRI) was investigated to determine the radiological correlates of cognitive deterioration in hereditary cerebral hemorrhage with amyloidosis-Dutch type (HCHWA-D). Twenty HCHWA-D subjects (12 patients who had suffered one or more strokes and eight who had not suffered a stroke) were studied with MRI and underwent extensive neuropsychological examination. On MRI the number of focal lesions was counted, and white matter hyperintensities (WMHs) were scored semiquantitatively. A significant correlation between cognitive deterioration and WMH score and number of focal lesions was found. However, cognitive deterioration, WMH score, and the number of focal lesions all increase with age, and therefore their mutual correlation can be explained as an age effect. This study shows that cognitive deterioration in HCHWA-D is not correlated with abnormalities detected by MRI (number of focal lesions and subcortical WMHs) independently of age. Although a contribution of white matter changes and/or focal lesions, possibly in combination with age, to cognitive deterioration cannot be excluded. Cognitive deterioration in these HCHWA-D patients is probably primarily the result of chronic damage of amyloid angiopathy to the brain, to which may be superimposed cognitive impairment from focal cerebral hemorrhage or infarction.

Adult↗

PubMed1996

Pulmonary function during the first year of life following acute viral bronchiolitis.

It has been suggested that acute viral bronchiolitis in infants may result in functional changes that predispose toward chronic pulmonary disease later in life. We assessed pulmonary function (PF) during the acute phase of viral bronchiolitis in infants and up to 12 mo later from static respiratory system compliance (Crs), using weighted spirometry, the distribution of ventilation by the mixing index (MI), and the functional residual capacity (FRC) measured by closed-circuit helium dilution (FRCHe). The study was performed in 24 infants (13 males and 11 females; median [25 to 75% range] age: 11 [9.6 to 13.3] wk; weight: 4.8 [4.3 to 5.0] kg; crown-to-heel length: 57.7 [55.5 to 59.0] cm) at admission and at 2 wk. In 17 infants, measurements were repeated 3 mo and 12 mo later. Predicted values and individual 95% prediction intervals for Crs, MI, and FRCHe were derived from 69 healthy infants (33 boys and 36 girls; median age [25 to 75% range]: 4.7 [2.0 to 21.4] wk; weight: 3.6 [3.0 to 6.9] kg; crown-to-heel length: 51.5 [48 to 61] cm). Data at admission and after discharge were compared by analysis of variance (ANOVA) with those in the healthy controls matched for crown-to-heel length. At admission all three variables gave lower average results than predicted means. Values for each index had attained a normal level 2 wk after admission; normal levels were maintained at 3 and 12 mo. The prevalence of recurrent wheezing (five of the 17 infants) was comparable with that reported in population studies. These findings suggest that in this population acute viral bronchiolitis did not lead to permanent changes in PF.

Acute Disease↗

PubMed1996

The relation between neonatal thyroxine levels and neurodevelopmental outcome at age 5 and 9 years in a national cohort of very preterm and/or very low birth weight infants.

Transient neonatal hypothyroxinemia is very common in preterm infants. The literature on the effect of this hypothyroxinemia is, however, controversial, and large or long-term follow-up studies are not available. In a nationwide prospective follow-up study on very preterm and (or) very low birth weight infants (n = 717), we studied the relationship between thyroxine levels in the 1st wk of life and neurodevelopmental outcome at 5 y of age and school performance at 9 y of age. Thyroxine concentrations from filter paper eluates were determined in 717 infants: 32% had levels of more than 3 SD below the mean (< 60 nmol/L). The percentage of infants with such low levels increased with decreasing gestational age. At the age of 5 y, 96% of survivors (n = 640) were available for extensive neurodevelopmental examination: 85 (13.3%) had a disability and 92 (14.3%) a handicap. At the age of 9 y, 83% of survivors (n = 552) answered a questionnaire on school performance: 300 (54.3%) were in mainstream education in a grade appropriate for age, 151 (27%) were in mainstream education with grade retention, and 101 (18.3%) were in special education. Both neurologic dysfunction at age 5 y and school failure at age 9 y were significantly related to lower neonatal thyroxine levels even after adjustment for other perinatal factors (odds ratio, 1.3). Whether this relationship is causal should be investigated. If a causal relationship exists, substitution therapy may at least partially prevent neurologic dysfunction and learning disabilities, both common sequelae of very preterm birth.

Birth Weight↗

PubMed1995

Predictive value of tetrapolar body impedance measurements for hydration status in critically ill patients.

OBJECTIVE: To design and evaluate a simple and rapid method to predict body hydration status in critically ill patients. DESIGN: Prospective, consecutive sample. SETTING: Medical intensive care unit of a university hospital. PATIENTS: 31 consecutive patients. METHODS: All patients were classified daily for hydration status by the attending physician based on clinical impression, weight changes and laboratory measurements. The hydration status was scored as 'dehydrated', 'euvolemic' or 'edematous'. The total body impedance was measured daily by a tetrapolar impedance technique. RESULTS: Resistances > 700 omega were found in dehydrated subjects and resistances of < 400 omega in edematous patients. Weight gain was observed in dehydrated and weight loss in edematous patients. A discriminant analysis was used to create a predictive model for hydration using the daily impedance and weight measurements. If a cutoff point of 60% for the predicted classification was used to categorize the patient's hydration as dehydrated, euvolemic and edematous, no false positive predictions were observed for the dehydrated or the edematous state. CONCLUSION: Impedance measurements are in close agreement with the clinical impression of hydration of critically ill patients. Future investigations must elucidate the clinical importance.

Adolescent↗

PubMed1995

Human osteoblasts from younger normal and osteoporotic donors show differences in proliferation and TGF beta-release in response to cyclic strain.

Mechanical stimulation of bone tissue by physical activity stimulates bone formation in normal bone and may attenuate bone loss of osteoporotic patients. However, altered responsiveness of osteoblasts in osteoporotic bone to mechanical stimuli may contribute to osteoporotic bone involution. The purpose of the present study was to investigate whether osteoblasts from osteoporotic patients and normal donors show differences in proliferation and TGF beta production in responses to cyclic strain. Human osteoblasts isolated from collagenase-treated bone explants of 10 osteoporotic patients (average age 70 +/- 6 yr) and 8 normal donors (average age 54 +/- 10 yr) were plated into elastic rectangular silicone dishes. Subconfluent cultures were stimulated by cyclic strain (1%, 1 Hz) in electromechanical cell stretching apparatus at three consecutive days for each 30 min. The cultures were assayed for proliferation, alkaline phosphatase activity and TGF beta release in each three parallel cultures. In all experiments, osteoblasts grown in the same elastic dishes but without mechanical stimulation served as controls. Significant differences between stimulated cultures and unstimulated controls were determined by a paired two-tailed Wilcoxon test. In comparison to the unstimulated controls, osteoblasts from normal donors significantly increased proliferation (p = 0.025) and TGF beta secretion (p = 0.009) into the conditioned culture medium. In contrast, osteoblasts from osteoporotic donors failed to increase both proliferation (p > 0.05) and TGF beta release (p > 0.05) in response to cyclic strain. Alkaline phosphatase activity was not significantly affected (p > 0.05) in normal as well as osteoporotic bone derived osteoblasts. These findings suggest a different responsiveness to 1% cyclic strain of osteoblasts isolated from normal and osteoporotic bone that could be influenced by both the disease of osteoporosis and the higher average age of the osteoporotic patient group. While osteoblasts from osteoporotic donors failed to increase proliferation and TGF beta release under the chosen mechanical strain regimen that stimulated both parameters in normal osteoblasts, it is possible that some other strain regimen would provide more effective stimulation of osteoporotic cells.

Age Factors↗

PubMed1995

Trends in caesarean section rates among high- and medium-risk pregnancies in The Netherlands 1983-1992.

During the last two decades, the rates of operative deliveries have been rising constantly in all industrialized countries including the Netherlands. Within the framework of the project 'Obstetric Peer Review' (Verloskundige Onderlinge Kwaliteitsspiegeling), the trends in the caesarean section rates were investigated, using the data of the Perinatal Database of the Netherlands (LVR), but only among the high- and medium-risk pregnancies. To that end homogeneous high-risk subgroups, with respect to pregnancy- or delivery-related complications, were defined in various ways and caesarean section rates were calculated for these groups. Irrespective of the definition of such a group (e.g. multiple pregnancy or breech presentation), an increase of the caesarean section rates evidently emerges. The rates of planned caesarean section appear to increase more than the rates of emergency caesarean section. The increase for the multiparae is greater than for the primiparae. It is striking that the largest increase was found within the medium-risk group (namely; singletons, at term, vertex presentation, normal birthweight, mothers aged 20-35 years and with a normal diastolic blood pressure). Although no evident pathology can be found in the data, these women do not belong to the low-risk group, because they were referred to an obstetrician. For the multiparae in this group, the risk of a planned caesarean section yearly increased by a factor 1.09 (i.e. 9%).

Adult↗

PubMed1995

Clinical and subclinical varicocele: a useful distinction?

OBJECTIVE: The purpose of the study was to establish whether it is useful to make a distinction between clinical and subclinical varicoceles with a view to deciding for treatment or not. Therefore, we compared our results of treatment of clinical vs. subclinical varicoceles. STUDY DESIGN: The changes of semen parameters and the occurrence of pregnancies in 40 infertile men treated for clinical varicocele were compared with those in 46 infertile men treated for subclinical varicocele. The significance of individual semen changes was analysed by paired t-test in both groups and the results of both groups were compared by analysis of covariance. The pregnancy rates were calculated and the life table curves of pregnancy of both groups were compared. RESULTS: There were statistically significant increments in sperm density, motility and morphology both after treatment of clinical and subclinical varicoceles, and these increments did not differ significantly between both groups. The cumulative pregnancy rates after a mean follow-up period of 6.6 years amounted to 42.5% for clinical varicoceles and to 39.1% for subclinical varicoceles and the life table curves of pregnancy ran a rather similar course in both groups. CONCLUSION: We conclude that there is no reason to emphasize the palpatory findings in infertile men with varicocele.

Adult↗

PubMed1995

Late outcomes of limb loss after failed infrainguinal bypass.

PURPOSE: Most reports regarding infrainguinal bypass surgical procedures demonstrate benefits well but pay less attention to adverse outcomes and consequences of failure for the patient. For a wider scope of infrainguinal bypass surgical procedures, we evaluated patient-oriented outcomes of limb loss occurring after failed infrainguinal bypass operations. METHODS: Eighty-one patients with vascular amputations were identified in a retrospective study. Follow-up was complete with a mean of 3.6 years. Life-table and multivariate analyses were used to assess factors influencing the desired outcome goals of rehabilitation. Mortality rates, social function, risk of contralateral amputation, and the ability to walk were used to measure the late outcome. RESULTS: The long-term survival rate was poor (72% at 1 year; 53% at 3 years) and was not related to traditional risk factors for atherosclerosis. Moreover the risk for contralateral amputation was 10% per year. One year after amputation 81% (47 of 58) of the surviving amputees were walking independently, and 73% (42 of 58) were living at home, 32 with their spouse. At 3 years these results were 73% (27 of 37) and 78% (29 of 37), respectively. In addition, the level of self-care changed significantly (p < 0.001) after amputation. Advanced age (older than 65 years), self-care performance, and living with someone were important predictors of late outcome. CONCLUSIONS: It is possible for a high percentage of patients with vascular amputations to return home successfully, either walking or in a wheelchair. Moreover this result can be predicted based on preoperative clinical variables. These data may be helpful to guide fitting of prosthetic devices, planning of discharge home, and use of health care resources.

Activities of Daily Living↗

PubMed1995

The potential of simple clinical information and electrocardiogram to predict mortality of primary elective abdominal aortic reconstruction.

OBJECTIVE: To assess the importance of simple clinical information to predict mortality after primary elective aortic reconstruction. DESIGN: Retrospective clinical study. MATERIALS: Four hundred-three consecutive patients (206 with aortic occlusive disease (51%) and 197 with aneurysmal disease of the abdominal aorta (49%) who underwent primary elective aortic reconstruction during an 8 year study period. METHODS: Eight potential clinical risk variables and six electrocardiogram related risk variables were studied. The predictive value for postoperative mortality was evaluated univariately for all separate variables by calculation of the odds ratio (OR). Determination of the most predictive sets of risk factors was performed by stepwise logistic regression. RESULTS: Five clinical risk factors showed significant odds ratio's: > 70 years (OR: 4.1), aortic aneurysm (OR: 9.0), myocardial infarction (OR: 8.6), angina pectoris (OR: 4.6), congestive heart failure (OR: 8.1), all p < 0.01. Furthermore, four electrocardiogram related factors showed significant odds ratio's: infarction pattern (OR: 4.3, p = 0.003), ischaemic changes (OR: 6.2, p < 0.001), conductance disturbances (OR: 3.2, p = 0.04), and non-sinus rhythm (OR: 6.2, p = 0.003). Stepwise logistic regression analysis demonstrated that 3 clinical risk factors (aneurysm (OR: 6.1, p = 0.02), myocardial infarction (OR: 3.7, p = 0.01), and congestive heart failure (OR: 5.3, p = 0.006)) contributed significantly to mortality. Addition of any of the electrocardiogram risk factors did not contribute to the prediction of mortality in the presence of these factors. CONCLUSIONS: The patients' history and clinical examination provides the most useful information for further selection of additional cardiac tests before elective primary aortic reconstruction. The additional value of the electrodiogram is somewhat overestimated.

Adult↗

PubMed1995

Respiratory illness in families of preterm infants with chronic lung disease.

AIMS--To examine the relation, based on two types of questionnaires, between (1) chronic lung disease of the newborn (CLDN) and lower respiratory illness (LRI) in siblings, and between (2) CLDN and asthma, chronic obstruction pulmonary disease (COPD), or allergy in parents and grandparents. METHODS--Data from 209 children born before 32 weeks of gestation were randomly taken from the records of three neonatal units. Taking into account age and gender, the excess of LRI was calculated for each family compared with the average of all families. Subsequently whether CLDN was associated with an excess of LRI in the family was tested. RESULTS--Thirty one (14.8%) children were diagnosed as having CLDN. The family probability index for LRI did not differ between children with or without CLDN. The prevalence of COPD, asthma, and allergy in parents of children with CLDN was similar to that of children without CLDN. The prevalence of LRI was 18.1% in study children, 29.6% in children with CLDN, and 16.9% in children without CLDN (P < 0.01). These prevalences were higher compared with that of a group of term siblings (9.3%) (P = 0.05). CONCLUSIONS--These findings suggest that CLDN in preterm children is not related to a genetic or familial predisposition towards asthma, COPD, or allergy.

Asthma↗

PubMed1995

Strength of the Breuer-Hering inflation reflex in term and preterm infants.

The effect of the presence of the respiratory distress syndrome (RDS) or related factors (static compliance of the respiratory system and transcutaneous blood gases) and gestational age on the strength of the Breuer-Hering inflation reflex (BHIR) was studied in three groups of infants. Twenty-six ventilated preterm infants with and without RDS were studied 6 h after birth (group 1). In 24 preterm infants, we followed the development of reflex strength during the first year of life (group 2). Twenty-one healthy nonintubated term infants were studied within the first week of life (group 3). The BHIR was initiated by end-inspiratory occlusions, and the strength was characterized by the ratio of expiratory time after and without preceding airway occlusion. The static compliance of the respiratory system in ventilated infants was assessed by the multiple-occlusion technique. In group 1, reflex strength declined with increasing gestational age; in the presence of RDS or low respiratory compliance, the decline was less. Transcutaneous blood gases did not affect reflex strength. At term age, reflex strength was similar in spontaneously breathing preterm (group 2) and term infants (group 3). The BHIR decreased in strength during the first year after preterm birth. We conclude that 1) the strength of the BHIR decreases with increasing gestational and postnatal ages and 2) RDS, due to changes in respiratory system mechanics, causes an increase in reflex strength.

Age Factors↗

PubMed1995

New imaging techniques in colorectal cancer.

The ability to visualize biochemical processes in tumor tissues by PET and correlate these findings with anatomic imaging such as CT and MRI gives new insight into the metabolic and physiologic aspects of the tumor tissue. This may permit discrimination between recurrent colorectal carcinoma and some benign lesions. The potential for its use in pharmacology or in monitoring drug therapy is just beginning to be explored. Improvements in acquisition techniques such as whole body imaging, and in methods of absolute quantitation will be important for standardizing image information and making it more widely applicable. Careful evaluation of the impact on patient outcome and clinical decision making are vital in determining the further use of this technology and the planned multicenter trial evaluating cost-effectiveness is welcome step in this direction.

Clinical Trials as Topic↗

PubMed1994

Transcription of repetitive DNA sequences in the lampbrush loop pair Nooses formed by sterile alleles of fertility gene Q on the Y chromosome of Drosophila hydei.

The Y chromosomal lampbrush loop-forming male fertility genes of Drosophila consist mainly of repetitive DNA sequences that do not code for proteins. We investigated whether differences in the transcription of these sequences can be detected in male-sterile alleles of male fertility gene Q, which forms the loop pair Nooses. The loop consists, for approximately two-thirds, of repeats of the Y-specific ay1 family of repetitive DNA sequences. Of the remaining one-third, at least one-half is represented by defective retrotransposons of the gypsy family. Both sequence types are interspersed throughout the loop. Using both ay1 and gypsy sequences as probes for transcript in situ hybridization, we show that, at the level of the light microscope, transcription of neither sequence is detectably affected in the loops formed by a male-sterile allele of gene Q. We conclude that the transcription of ay1 and gypsy is required, but not sufficient for the function of gene Q.

Alleles↗

PubMed1994

[Postoperative pain control in The Netherlands].

OBJECTIVE: To determine how postoperative analgesia care is managed in the Netherlands. DESIGN: Descriptive study (questionnaire). SETTING: Departments of anaesthesiology in all 168 Dutch hospitals. METHOD: Questionnaires were sent inquiring about postoperative pain therapies and their complications, the organisation and management of postoperative analgesic care, the importance of effective pain control, factors of influence on patient's assessment of pain and the management of the quality of postoperative analgesia. RESULTS: The questionnaires of 73% (n = 122) of the hospitals were suitable for analysis. Locoregional analgesic techniques are used, but intermittent intramuscular administration of an opioid is still the analgesic therapy of choice in the postoperative period. 89% of the interviewed anaesthesiologists assess the average intensity of postoperative pain as moderate or severe, and more than half of the interviewed anaesthesiologists answered that effective postoperative pain management is of substantial influence on the postoperative recovery of the patient. CONCLUSION: It is essential to improve postoperative pain control in the Netherlands. Frequent assessments and precise documentation of the intensity of pain and pain relief, on which further therapy can be based, might be a first step in improving postoperative pain control. Optimal postoperative pain management requires the input of equipment and staff.

Analgesia↗

PubMed1994

Differences in obstetrical intervention rates between Dutch hospitals.

Within the framework of the project 'Obstetric Peer Review' (Verloskundige Onderlinge Kwaliteitsspiegeling, VOKS) differences between Dutch hospitals concerning various obstetrical interventions were investigated. Using data of the Perinatal Database of the Netherlands from hospitals with at least 2000 newborns in the 5-year period 1987-1991, remarkable differences in frequencies of labour induction, caesarean section and vaginal operative deliveries can be shown, even when these interventions were considered within homogeneous subgroups with respect to pregnancy- or delivery-related complications. The incidence of caesarean section (and labour induction and vaginal operative delivery) appeared to depend more on the specific hospital policy than might be explained by populations differences alone. These intervention differences between hospitals clearly demonstrated the need to carry out a multivariate analysis to compare hospitals in a relevant and unbiased way, while adjusting for these population differences. This will estimate the intervention risks in a way which allows a fair comparison of hospital intervention policies.

Cesarean Section↗

PubMed1994

[Birth weight percentiles of premature infants needs to be updated].

OBJECTIVE: To analyse whether the conventional so-called Kloosterman charts for birthweight of preterm infants based on data from 1931-1965 are still valid. DESIGN: Descriptive investigation. LOCATION: The Netherlands. METHOD: Data were obtained from the 'project of the premature and small for gestational age' (POPS) survey in 1983. The population consisted of 855 Caucasian infants born after a pregnancy of 24-31 weeks. RESULTS: In nearly all gestational age categories the percentages of small-for-gestational age infants were higher than the 10% they should have been by definition; the percentages of large-for-gestational age infants were much lower than 10%. After exclusion of elective births the percentages remained different. CONCLUSION: These shifts in the birthweight distribution are probably the result of changes in obstetrics. The birthweight percentiles for preterm births will have to be updated.

Birth Weight↗

PubMed1994

Aortoiliac and aortofemoral reconstruction of obstructive disease.

This retrospective study evaluates our strategy to limit prosthetic reconstructions for aortoiliac obstructive disease to the diseased segments in 518 patients. There were 363 (70%) reconstructions without femoral anastomotic sites (FEM-0), 107 (21%) reconstructions with one femoral anastomotic site (FEM-1), and 48 (9%) aortobifemoral reconstructions (FEM-2). The ischemic symptoms and the extent of obstructions were significantly more severe in the FEM-1 and FEM-2 groups than in the FEM-0 group. Early operative results were comparable in all three groups. The difference in outcome became apparent when the long-term results were considered. Long-term follow-up continued for up to 20 years after the operation. Primary and secondary patency rates were significantly higher in the FEM-0 group (9% and 4% recurrent obstructions per 5 years, respectively) than in the FEM-1 and FEM-2 groups (both 14% and 10%, respectively), which was explained by patient selection. Late additional surgery was performed after aortoiliac procedures in most cases for recurrent aortoiliac obstruction and after aortofemoral procedures in most cases for false aneurysms. The risk of late additional operations during long-term follow-up were significantly lower in the FEM-0 group than in the FEM-1 and FEM-2 groups. These results support our strategy to tailor prosthetic reconstructive surgery to the individual status of the aortoiliac arteries.

Aorta, Abdominal↗

PubMed1994

How to compare and report department specific mortality rates for peer review using the Perinatal Database of The Netherlands.

Since characteristics of patient populations of obstetric departments vary substantially with respect to the pathology presented, (perinatal) mortality rates as such can not be used for a fair peer review without adjustment for those differences. Using the Perinatal Database of The Netherlands (LVR), data on approximately 80,000 newborns annually from 1985 to 1991 inclusive were used in statistical models to predict the perinatal mortality risks of four subpopulations of different gestational age in about 125 obstetric departments. As predictors for perinatal mortality we used only those risk factors which were judged to reflect the 'pathology' of the patient; risk factors associated with or resulting from hospital care and/or policy are (by definition) excluded. The statistical technique of logistic regression was used. The expected and observed mortality within each of these four subpopulations (for 1985-1991) was sent anonymously to each department as a specially designed graphical overview. This method of (anonymous) peer review was met favourably. In peer review the difference between observed and expected mortality should be used, rather than mortality per se, to adjust for differences in basic risk in the intake populations on which the departmental policy has no influence.

Gestational Age↗