Biomedical subjects

P G Mulder

Publications and source records attributed to P G Mulder.

At least 19 recordsLinked to original sources

PubMed1992

[Immunologically mediated contact urticaria caused by foods in young children with constitutional eczema].

Fifty-two children with atopic dermatitis were investigated with the mixed-food radio-allergosorbent test (RAST) and the skin provocation test 'Skin Application Food Test' (SAFT). The mixed-food RAST is a commercially available test with multiple allergens on one disk. The disk contains 6 common food allergens: cow's milk, egg, peanut, soy, codfish and wheat. The SAFT is a system with which foods are applied to the skin in the state in which they are consumed. This test system is routinely used in our subdivision of Paediatric Dermatology in Sophia Children's Hospital. In some children, atopic dermatitis grew worse after a positive SAFT reaction. In 50% of the 38 children with food allergy a correlation was found between exacerbation/induction of atopic dermatitis and consumption or direct skin contact of foods to which the child was allergic. Due to direct skin contact of foods, atopic dermatitis can grow worse with sudden attacks of pruritus, especially on the hands and in the face. The SAFT imitates the naturally occurring symptoms, is child friendly and easy to perform. The mixed-food RAST can be used as a screening test to identify the children with atopic dermatitis and an atopic immune response to foods, so possibly food allergy. Further investigations of the sensitivity of the target organ (in atopic dermatitis: the skin) and the usefulness of the SAFT are then indicated.

Child, Preschool↗

PubMed1992

Retinal vessel autoregulation in sickle cell patients.

We tested retinal vessel autoregulation in 16 sickle cell patients and 6 controls by computer-assisted measurements of constriction of the superior and inferior temporal veins and arteries after pure oxygen breathing. Compared to the controls and corrected for age, we found a decrease of vasoconstriction in three of the four vessels measured in the sickle cell group, which was statistically significant only for the superior temporal artery (P 0.009). The number of patients was too small to allow a separate analysis of possible contributory factors within the sickle cell group, such as sickle cell hemoglobin subtype and extent of retinal ischemia. Our findings indicate a factor not yet well known in the pathophysiology of sickle cell disease: an abnormality of local microvascular control.

Adult↗

PubMed1992

Histologic features of the early stages of age-related macular degeneration. A statistical analysis.

The age distribution, frequency, and correlation among histologic macular changes, including formation of a basal laminar deposit, drusen, and thickening and calcification of Bruch's membrane, were studied by light microscopy. The authors studied 182 unpaired postmortem human maculae from patients between 8 and 100 years of age. In addition, 45 maculae of contralateral eyes and the peripheral retina of 50 eyes were studied. In 92%, Bruch's membrane was thickened starting at age 19, and calcifications in this membrane were found in 59% starting at age 33. In 37% of the maculae, hard drusen were found starting at age 34. Soft drusen were found in 10% beginning at age 54. Basal laminar deposit was found in 39% of the maculae starting at age 40. All changes correlated strongly with age (P less than 0.0001). No sex differences were found. Fellow eyes showed similar aging changes (P less than 0.001). The presence of basal laminar deposit in the macula correlated with basal laminar deposit-like material in the peripheral retina (correlation coefficient, 0.39; P less than 0.003), whereas drusen in the macula correlated with drusen in the peripheral retina (correlation coefficient, 0.42; P = 0.001). Geographic atrophy was found in 6.6% of the eyes from subjects older than 70 years and subretinal neovascularization in 3.8%, especially in the maculae with basal laminar deposit.

Adolescent↗

PubMed1992

Dynamics of mast cells in the nasal mucosa of patients with allergic rhinitis and non-allergic controls: a biopsy study.

Mast cell degranulation is thought to be an important component of the pathogenesis of allergic rhinitis. Quantitative studies on mast cells in nasal mucosa after allergen exposure have given widely divergent results, ranging from an overall decrease via redistribution to an overall increase. We investigated this problem by employing a combination of anti-IgE and toluidine blue staining of biopsy specimens. In allergic patients anti-IgE was found to identify all mast cells and toluidine blue to detect mast cells that were not (totally) degranulated. The study was composed of two parts done in different patient groups. In the first part of the study biopsies were performed in 23 patients with isolated grass-pollen allergy, once during natural provocation in the summer and once in the winter. Biopsies were also performed in 12 controls. Non-allergic controls were found to have the same number of mast cells in the lamina propria as asymptomatic allergic patients. The controls seldom have mast cells in the epithelium. The patients with isolated grass-pollen allergy showed an increase in the numbers of mast cells in the lamina propria during natural provocation and the same seemed to occur in the epithelium as well. During natural provocation almost all of the mast cells in the epithelium and half of those in the lamina propria were degranulated. In the second part of the study 17 patients with isolated grass-pollen allergy and four controls were challenged daily with allergen extract during a 2-week period in the winter. During this period biopsies were performed at eight different occasions, i.e. once before, six occasions during and once after the provocation period. The results of this part of the study showed that during provocation mast cells migrate to the surface of the nasal mucosa, where they become degranulated, and that the pool of mast cells in the lamina propria was apparently replenished by migration of mast cells from the vessels in the lamina propria. The total number of mast cells in the lamina propria remained approximately the same while the mast cells residing in an increasingly thick layer measured from the basal membrane into the lamina propria became degranulated. After 2 weeks, 82% of the mast cells in the lamina propria was degranulated and it was only in the deepest layers that some toluidine blue positive cells were found.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

PubMed1992

Hepatocellular carcinoma in porphyria cutanea tarda: frequency and factors related to its occurrence.

Thirty-eight patients with porphyria cutanea tarda (PCT) have been seen in the last 18 years. Five of these patients (13%) developed hepatocellular carcinoma (HCC) during follow-up. We analyzed the differences in clinical, laboratory and liver histology findings at presentation, between patients who developed HCC during follow-up (HCC-group, n = 5) and those who did not (PCT-group, n = 33). Of the clinical features the duration of skin-symptoms was longer in the HCC-group (mean: 10.4 +/- 1.1 years) than in the PCT-group (mean: 1.4 +/- 1 years) (p less than 0.001). No differences in routine laboratory findings were found. Although 11/38 (29%) patients had serologic evidence of a past hepatitis B virus infection and 7/38 (18%) patients had antibodies against hepatitis C virus, no differences in these parameters were found between the PCT-group and the HCC-group. In all 34 liver biopsies a variable degree of siderosis was found (PCT-group vs. HCC-group: NS). Only piecemeal necrosis (p less than 0.01) and advanced fibrosis or cirrhosis (p less than 0.001) were more common in liver biopsies in the HCC-group. In conclusion, factors related to an increased risk of HCC in PCT are: a) a long symptomatic period before start of treatment and b) the presence of chronic active hepatitis and/or advanced fibrosis or cirrhosis in liver biopsies.

Adult↗

PubMed1992

Food immediate-contact hypersensitivity (FICH) and elimination diet in young children with atopic dermatitis. Preliminary results in 107 children.

In atopic dermatitis [AD], not only food consumption, but direct skin-contact too can provoke hypersensitivity reactions. We imitated food immediate-contact hypersensitivity [FICH] to cow's milk, egg, peanut or soy by a skin provocation test. This skin application food test [SAFT] was applied in 91 patients aged up to 5 years and suffering from AD, and in 16 healthy controls (all SAFT-negative). In the SAFT-positive patients (n = 61), FICH to egg was observed in 72%, to cow's milk in 47%, to peanut in 34% and soy in only 1 patient. SAFT and RAST scores correlated weakly. Nevertheless, many discrepancies between SAFT and RAST results were found. In 20 of the 61 (33%) patients with FICH, a flare-up in AD was noted at SAFT testing. Upon introducing dietary restrictions, AD improved impressively in 9 of 23 patients who could be followed up. FICH is an important symptom in children with AD and food allergy.

Arachis↗

PubMed1991

Intravenous immunoglobulin treatment in patients with chronic inflammatory demyelinating polyneuropathy. Clinical and laboratory characteristics associated with improvement.

Of 52 patients fulfilling the criteria of chronic inflammatory demyelinating polyneuropathy, 20 (38%) did not improve after intravenous immunoglobulin treatment, two (4%) had a short-lasting improvement and subsequent infusions had no effect, nine (17%) reached a spontaneously or therapeutically induced complete remission, and 21 patients (40%) needed intermittent infusions to maintain improvement. All patients who improved initially had symptoms that significantly interfered with life-style. After treatment, 90% of these patients were independent in their daily activities. Significantly associated with improvement were disease duration of less than 1 year, progression of weakness until treatment, absence of discrepancy in weakness between arms and legs, areflexia of the arms, and slowed nerve conduction velocity of the motor median nerve. The probability of improvement if all these features are present in 93%.

Adolescent↗

PubMed1991

Posture control and the risk of industrial accident: a stabilographic investigation in a naval shipyard.

In a previous case-control study on the effect of impaired perceptual acuity on the risk of industrial injuries at a naval shipyard, three factors which might influence the perception and processing of sensory impressions--alcohol consumption, hearing loss exceeding 20 decibels (dB) and exposure to noise exceeding 82 dB(A)--were found to contribute to the risk of injury. According to recent reports, these factors can all lead to impaired posture control. Because in general about 40% of all accidents are associated with falling, tripping, slipping and the like, a supplementary study has been carried out to unravel possible confounding effects of posture control on these three risk factors. Cases (who had suffered two or more accidents during the preceding 4 years) and controls (who had been accident-free in the same period) were compared as regards posture control measured during silence or noise. No significant difference in posture control was found between cases and controls, either in silence or during exposure to heavy noise.

Accidents, Occupational↗

PubMed1991

Influenza: relation of mortality to morbidity parameters--Netherlands, 1970-1989.

The purpose of this study is to investigate the relationship between the number of influenza-like illness (ILI), weekly registered by the general practitioners (sentinel stations), and the monthly overall influenza mortality in people over 60 years of age, provided by the Dutch Statistical Bureau during the period July 1970 to June 1989. The quantitative impact of influenza-morbidity is expressed by three summary parameters, calculated from the 52 (53) weekly ILI-figures per season-year, (i) their sum (i.e. global extent of an epidemic), (ii) their standard deviation, and (iii) their maximum (i.e. peak number of ILI during an epidemic). In the analysis influenza A subtype is also included. These four parameters are mutually compared with respect to their predictability for yearly total influenza mortality in the 19 season-years available. In most cases, the standard deviation and the peak number of ILI are more powerful for prediction of mortality, than the global extent of the epidemic. The peak number of ILI is of special interest. It is particularly useful for estimating the effect on current influenza mortality during an ongoing epidemic. From the model it is possible to calculate a threshold (of weekly ILI) beyond which mortality increases proportionately more than the number of illness episodes. By using the peak value of morbidity it is possible to calculate the minimal impact of epidemic mortality. This study indicates that the weekly number of influenza-like illnesses has a certain prognostic value for the real impact of influenza. An electronic surveillance system could detect immediately the threshold above which influenza mortality increases more than proportionally.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

von Willebrand factor and development of diabetic nephropathy in IDDM.

We tested the hypothesis that dysfunction of vascular endothelium, indicated by an increase in plasma level of von Willebrand factor (vWF), is present in patients with insulin-dependent diabetes mellitus (IDDM) who develop diabetic nephropathy (DN). DN was classified as absent (urinary albumin excretion [UAE] rate less than 15 microgram/min), incipient (UAE rate 15-200 micrograms/min), or clinical (UAE rate greater than 200 micrograms/min). We followed a cohort of 59 patients for a median of 3 yr. At baseline, 52 patients had no DN, 6 had incipient DN, and 1 had clinical DN. At follow-up, 38 patients had no DN (group 1). Incipient DN had developed in 14 patients and worsened in 3 patients. Clinical DN had worsened in 1 patient. Together, these 18 patients comprised group 2. A decrease in UAE was observed in the remaining three patients with incipient DN at baseline (group 3). In group 1, vWF--measured by immunoelectrophoresis and expressed as a percentage of normal--increased slightly (median 10%, range -43 to 145, P = 0.009). In group 2, vWF increased in all patients (median 80%, range 14 to 206 [corrected], P = 0.0002 vs. baseline and group 1). In group 3, vWF decreased (median -19%, range -44 to -18). After correction for possible confounders, i.e., age, varying duration of follow-up, and initial level of vWF, the difference in vWF change between groups 1 and 2 remained significant (P = 0.009). Poor glycemic control at baseline, estimated by glycosylated hemoglobin, was a significant predictor of increases in vWF in both group 1 and groups 1 and 2 combined.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

Immediate contact reactions to cow's milk and egg in atopic children.

Forty children (0-5 years old), presented with immediate contact urticaria, rash and often atopic dermatitis (n = 34). Redness or urticaria around the mouth appearing after consuming cow's milk or egg, were the major complaints in all. These symptoms suggested a food-induced immediate contact reaction, which can be immune-mediated or irritative. To reinduce this reaction, a skin provocation test, called SAFT, was performed. SAFT stands for Skin Application Food Test. This test is based on direct skin contact, during a maximum of 30 min with food in its 'ordinary consumptive state'. The SAFT can be regarded as a 'physiological' provocation patch test. If positive, contact urticaria develops most often within a few minutes. The results of SAFT and IgE RAST correlated significantly well. Total IgE values were not informative. The rapid onset of the SAFT reaction, induced by proteins, supported by RAST results, strongly indicates an immune-mediated mechanism. In 52% of the 34 patients with atopic dermatitis, dermatitis was exacerbated following food-to-skin contact. Immune-mediated contact reactions to foods play an important role in (dermal) food allergy.

Child, Preschool↗

PubMed1990

Seasonal variations in binding of 3H-paroxetine to blood platelets in healthy volunteers: indications for a gender difference.

Binding of paroxetine to blood platelet membranes was studied longitudinally in 20 healthy volunteers (11 men and 9 women) in order to determine seasonal and gender variations. Blood samples were obtained in September, December, March, and June, and repeated in September. A significant seasonal variation in the maximal number of binding sites (Bmax) was found. Men were found to have significantly lower (Bmax) values than women. Although the pattern of seasonal variation was not identical in men and women, no significant differences were detected. The affinity constant (KD) of paroxetine binding showed a significant seasonal variation. Men were found to have a significantly higher KD (lower affinity) than women. The pattern of seasonal variation was identical in men and women. These data support the evidence indicating a substantial seasonal effect on the serotonergic system, and show that in paroxetine binding studies, groups of subjects should be matched for season and gender.

Adult↗

PubMed1990

Non-familial degenerative disease and atrophy of brainstem and cerebellum. Clinical and CT data in 47 patients.

We studied the clinical features of 47 patients with a non-hereditary degenerative disease and with atrophy of brainstem or cerebellum or both in CT scanning. There was no relation between the CT findings and duration or severity of the disease, nor with the kind of the neurological signs which comprised ataxia, a hypokinetic rigid syndrome, oculomotor abnormalities, upper and lower motor neuron signs, orthostatic hypotension and dementia. The 2 main diagnoses were olivopontocerebellar atrophy (OPCA), or a combination of OPCA and striatonigral degeneration (SND). The differential diagnosis with Parkinson's disease and progressive supranuclear palsy was discussed. We concluded, that a CT scan is warranted in all cases of suspected Parkinson's disease, especially in those without tremor, and in cases of motoneuron disease with broad-based gait. In our patients with mainly hypokinesia and rigidity, levodopa treatment had no or brief beneficial effects. If ataxia predominated, OPCA appeared the most sensible diagnosis; if a hypokinetic-rigid syndrome predominated, the diagnoses SND plus OPCA appeared the most suitable. We assessed the degree of atrophy on CT subjectively, because an interobserver study of 60 normal CT scans, did not produce reliable measurements.

Adult↗

PubMed1990

Ki-67 immunostaining in uveal melanoma. The effect of pre-enucleation radiotherapy.

The reactivity of 33 choroidal and ciliary body melanomas with monoclonal antibody Ki-67, which recognizes a proliferation associated nuclear antigen, has been assessed and compared with clinicopathologic parameters. In 23 cases, 8 Gy irradiation was given 2 days before enucleation. Nonirradiated melanomas had a significantly higher proliferation rate as defined by staining with monoclonal antibody Ki-67 as compared with irradiated tumors (P = 0.007). Similarly, a strong relationship was found between pre-enucleation irradiation and low mitotic activity (P = 0.001). There was no significant correlation between the presence of Ki-67-positive nuclei and histologic classification, largest tumor diameter, localization of the tumor, age, sex, scleral invasion, pigmentation, and lymphocytic infiltration. The relevance of Ki-67 immunohistochemistry for the assessment of the life prognosis of patients with uveal melanoma has to be studied prospectively.

Antibodies, Monoclonal↗

PubMed1990

Perceptual acuity and the risk of industrial accidents.

A case-control study of the risk of injuries incurred by male shipyard workers in Den Helder, The Netherlands, was carried out in 1986-1987. The main focus of interest was factors which can interfere with faculties needed for recognizing warning signals of imminent danger. Three hundred workers who had had at least one injury in the previous 3 1/2 years and 300 matched controls were asked about their current use of alcohol, tranquilizers, and cigarettes; the wearing of spectacles and earplugs; taking a nap at noon; engaging in sports during leisure hours; and involvement in a traffic accident during the past year. The hearing acuity of most of the workers involved in the study, as well as the noise load at work, had been recently assessed. Alcohol consumption, hearing loss greater than 20 dB, and loud noise greater than 82 dB(A) were found to be safety hazards. At this shipyard, the risks attributable to noise and hearing loss together accounted for 43% of the injuries.

Accidents, Occupational↗

PubMed1990

Histological grading of prostatic carcinoma in prostatectomy specimens. Comparison of prognostic accuracy of five grading systems.

The prognostic accuracy of 5 histological grading systems (Broders, Anderson, Mostofi, Gleason and Mostofi-Schroeder) was compared. Grading was performed on 50 prostatectomy specimens by 5 pathologists. The results were averaged so as to reduce the impact of inter-observer variation. The Cox proportional hazards model was used to estimate the relationship between average grading scores and both time-to-recurrence and time-to-death by prostatic carcinoma. Age at surgery was considered to be a possible confounding factor and adjusted accordingly. The prognostic impact of the 5 grading systems (related to both recurrence and death caused by prostatic carcinoma) was judged by the likelihood ratio (LR) test score (chi 2 distributed with 1 df); for time-to-recurrence for the Mostofi-Schroeder score the LR was 6.54 and for the Gleason system it was 1.79. A stepwise procedure demonstrated that the best prognostic performance was reached with the Mostofi-Schroeder and Broders systems used together (with Mostofi-Schroeder weighted 1.5 times larger than Broders). For time-to-recurrence the median grading result was also used, giving results similar to the mean grading result. For time-to-death from prostatic carcinoma the LR test scores for all grading systems were relatively low. In this analysis the outcome of the Gleason system showed a minimum of prognostic ability, whereas the Broders and Mostofi-Schroeder systems had a reasonable predictive ability. Since the inter-observer variation of the Mostofi-Schroeder system was large, the Broders system is preferable. The restrictions and implications of this study are discussed and a brief review of the prognostic importance of grading of prostatic carcinoma is presented.

Aged↗

PubMed1990

Pharmacokinetics of ceftazidime in serum and suction blister fluid during continuous and intermittent infusions in healthy volunteers.

The pharmacokinetics of ceftazidime were investigated during intermittent (II) and continuous (CI) infusion in eight healthy male volunteers in a crossover fashion. The total daily dose was 75 mg/kg of body weight per 24 h in both regimens, given in three doses of 25 mg/kg/8 h (II) or 60 mg/kg/24 h with 15 mg/kg as a loading dose (CI). After the third dose (II) and during CI, serum and blister fluid samples were taken. Seven new blisters were raised for each timed sample by a suction blister technique. Blisters took 90 min to form. Samples were then taken from four blisters (A samples) and 1 h later were taken from the remaining three (B samples). The concentration of ceftazidime was determined using a high-performance liquid chromatography method. After II, the concentrations in serum immediately after infusion (t = 30 min) and 8 h after the start of the infusion were 137.9 (standard deviation [SD], 27.5) and 4.0 (SD, 0.7) micrograms/ml, respectively. The half-life at alpha phase (t1/2 alpha) was 9.6 min (SD, 4.6), t1/2 beta was 94.8 min (SD, 5.4), area under the concentration-time curve (AUC) was 285.4 micrograms.h/ml (SD, 22.7), total body clearance was 0.115 liter/h.kg (SD, 0.022), and volume of distribution at steady state was 0.178 liter/kg (SD, 0.023). The blister fluid (A) samples showed a decline in concentration parallel to that of the concentrations in serum during the elimination phase with a ratio of 1:1. The t1/2 of the A samples was 96.4 min (SD, 3.2). The concentration of ceftazidime in the B blister fluid samples was significantly higher (27%) than in the A samples over time. This shows that blisters may behave as a separate compartment and establishes the need to raise new blisters for each timed sample. The mean AUC/h during continuous infusion was 21.3 micrograms . h/ml (SD, 3.0). The total body clearance was 0.113 liter/h . kg (SD, 0.018), the urinary clearance was 0.105 liter/h . kg (SD, 0.012), and the ceftazidime/creatinine clearance ratio was 0.885. The mean AUC of blister fluid per hour was 84.5% (18.0 micrograms . h/liter; SD, 3.6) compared with that of serum. The A samples did not differ significantly from the B samples. The implications of continuous infusion of beta-lactams for treatment of serious infections are discussed.

Adult↗

PubMed1990

Screening for cervical Chlamydia trachomatis infections in two Dutch populations.

Endocervical cultures for Chlamydia trachomatis and Neisseria gonorrhoeae were taken from 492 women attending an outpatient clinic for sexually transmitted diseases (group I) and 560 women seeking legal abortion (group II). Possible risk factors for C trachomatis infection were evaluated by multivariate analysis. The prevalence rates for C trachomatis and N gonorrhoeae were 7.3% and 2.5% in group I and 9.4% and 0.4% in group II. From multivariate analysis it was found that age (p less than 0.01), number of sexual partners (p less than 0.01), abnormal vaginal discharge (p less than 0.01), and endocervical mucopus (p = 0.02) were independently associated with chlamydial infection in group I. In the abortion clinic age (p = 0.03) and endocervical mucopus (p = 0.03) were the only significant independent predictors of C trachomatis. In all women vaginal discharge was collected for Gram staining. A significant higher number of polymorphonuclear cells was seen in the smears of C trachomatis positive women (group I: p = 0.04; group II: p = 0.03). In group II there was also a significant association between C trachomatis and Gardnerella type bacterial flora (p = 0.02) and the presence of comma-shaped rods (p = 0.04). Screening for C trachomatis infection may help to decrease the incidence of (post-abortal) pelvic inflammatory disease. Because screening in abortion clinics is not always possible, decreasing the incidence of postabortal pelvic inflammatory disease could be achieved by using prophylactic antibiotics. Selective use of prophylaxis in high risk patients can minimise costs and the incidence of side effects.

Adult↗