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A Ott

Publications and source records attributed to A Ott.

At least 73 records · Page 4Linked to original sources
PubMed1996

Relationship between clinical severity of respiratory syncytial virus infection and subtype.

The relationship between clinical severity of respiratory syncytial virus (RSV) infection and distribution of subtype A or B was investigated. The data of 232 children, who were admitted with RSV infection or diagnosed in the outpatient department of the Sophia Children's Hospital, Rotterdam between 1992 and 1995, were studied. The diagnosis of RSV was confirmed by a direct immunofluorescence assay. Subtyping was performed by an indirect immunofluorescence assay using specific monoclonal antibodies. Gender, age at diagnosis, gestational age and birth weight, the presence of underlying diseases, feeding difficulties, the presence of wheezing and retractions, respiratory rate, temperature, clinical diagnosis at presentation, oxygen saturation (SaO2), carbon dioxide tension (PCO2), and pH, characteristics of hospitalisation, and the need for mechanical ventilation were observed. Analysis was performed on data from all patients diagnosed with RSV infection in the period between 1992 and 1995 spanning three RSV seasons, and separately on the RSV season 1993-4. The outcome of the three year analysis (150 (64.7%) subtype A v 82 (35.3%) subtype B) was compared with the outcome of the season 1993-4, a mixed epidemic with 37 (60.7%) subtype A and 24 (39.3%) subtype B isolates. None of the variables observed in the season 1993-4 differed significantly between RSV subtype A and B. Similar results were obtained from the analysis in the period 1992 until 1995, with the exception of PCO2 (a higher PCO2 was found in subtype A, p < 0.001) and retractions (more retractions were noted in patients with subtype A, p = 0.03). After correcting for possible confounders using regression analysis, these differences were not significant anymore. The data indicate that there is no relationship between clinical severity of RSV infection and subtype.

Carbon Dioxide↗
PubMed1995

Prevalence of Alzheimer's disease and vascular dementia: association with education. The Rotterdam study.

OBJECTIVE: To estimate the prevalence of dementia and its subtypes in the general population and examine the relation of the disease to education. DESIGN: Population based cross sectional study. SETTING: Ommoord, a suburb of Rotterdam. SUBJECTS: 7528 participants of the Rotterdam study aged 55-106 years. RESULTS: 474 cases of dementia were detected, giving an overall prevalence of 6.3%. Prevalence ranged from 0.4% (5/1181 subjects) at age 55-59 years to 43.2% (19/44) at 95 years and over. Alzheimer's disease was the main subdiagnosis (339 cases; 72%); it was also the main cause of the pronounced increase in dementia with age. The relative proportion of vascular dementia (76 cases; 16%), Parkinson's disease dementia (30; 6%), and other dementias (24; 5%) decreased with age. A substantially higher prevalence of dementia was found in subjects with a low level of education. The association with education was not due to confounding by cardiovascular disease. CONCLUSIONS: The prevalence of dementia increases exponentially with age. About one third of the population aged 85 and over has dementia. Three quarters of all dementia is due to Alzheimer's disease. In this study an inverse dose-response relation was found between education and dementia--in particular, Alzheimer's disease.

Aged↗
PubMed1995

Flexibility of myosin attachment to surfaces influences F-actin motion.

We have analyzed the dependence of actin filament sliding movement on the mode of myosin attachment to surfaces. Monoclonal antibodies (mAbs) that bind to three distinct sites were used to tether myosin to nitrocellulose-coated glass. One antibody reacts with an epitope on the regulatory light chain (LC2) located at the head-rod junction. The other two react with sites in the rod domain, one in the S2 region near the S2-LMM hinge, and the other at the C terminus of the myosin rod. This method of attachment provides a means of controlling the flexibility and density of myosin on the surface. Fast skeletal muscle myosin monomers were bound to the surfaces through the specific interaction with these mAbs, and the sliding movement of fluorescently labeled actin filaments was analyzed by video microscopy. Each of these antibodies produced stable myosin-coated surfaces that supported uniform motion of actin over the course of several hours. Attachment of myosin through the anti-S2 and anti-LMM mAbs yielded significantly higher velocities (10 microns/s at 30 degrees C) than attachment through anti-LC2 (4-5 microns/s at 30 degrees C). For each antibody, we observed a characteristic value of the myosin density for the onset of F-actin motion and a second critical density for velocity saturation. The specific mode of attachment influences the velocity of actin filaments and the characteristic surface density needed to support movement.

Actins↗
PubMed1995

Prevalence of Parkinson's disease in the elderly: the Rotterdam Study.

We assessed the prevalence of Parkinson's disease (PD) in a general elderly population in the Netherlands. The study formed part of the Rotterdam Study, a population-based door-to-door study, and included 6,969 persons 55 years of age or older living in a suburb of Rotterdam, the Netherlands. All participants were examined, and those who either had at least one possible cardinal sign of parkinsonism at the neurologic screening, reported that they had PD, or were taking antiparkinsonian drugs were invited for further evaluation. The prevalence of PD in this population was 1.4% (1.2% for men, 1.5% for women). Prevalence increased with age, and prevalence figures were 0.3% for those aged 55 to 64 years, 1.0% for those 65 to 74, 3.1% for those 75 to 84, and 4.3% for those 85 to 94. The corresponding age-specific figures for men were 0.4%, 1.2%, 2.7%, and 3.0%, and for women, 0.2%, 0.8%, 3.4%, and 4.8%. Among 95- to 99-year-old women the prevalence was 5.0%. Twelve percent of the subjects with PD were detected through the screening and had not been diagnosed previously.

Age Distribution↗
PubMed1995

Do nonsteroidal anti-inflammatory drugs decrease the risk for Alzheimer's disease? The Rotterdam Study.

Based on reports that the use of nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the risk for Alzheimer's disease (AD), we studied the cross-sectional relation between NSAID use and the risk for AD in a population-based study of disease and disability in older people. After controlling for age, education, gender, and use of benzodiazepines, we found a relative risk (RR) for AD of 0.38 (0.15 to 0.95) when comparing NSAID users (n = 365) to NSAID non-users (n = 5,893). To address confounding by indication or contraindication, we compared NSAID users with a subset of NSAID non-users who were using topical medication for ear, eye, or dermatologic conditions (n = 365). In this comparison, the adjusted RR for AD was 0.54 (0.16 to 1.78). These findings are compatible with a possible protective effect of NSAIDs on the risk for AD.

Aged↗
PubMed1993

Pharmacokinetic model for the absorption of subcutaneously injected soluble insulin and monomeric insulin analogues.

A subcutaneous insulin absorption model is presented for parameter estimation from the time course of plasma insulin. Modifications of a published model were made for the absorption of soluble insulin and monomeric insulin analogues in the range of therapeutic concentrations and volumes. The modified diffusion-dissociation model with distributed parameters was approximated by a multiple-compartment model. Subcutaneous absorption of soluble insulin and monomeric insulin analogues with various volumes, concentrations, and injection depths was simulated. The model for soluble insulin exhibits volume, concentration, and injection depth dependent absorption, as experimentally observed. It was found that binding of soluble insulin in the subcutaneous tissue is negligible for U-40 and U-100 strengths. The absorption of identical doses (10 U) of soluble U-40 insulin was markedly faster (T-50% = 159.4 min) than the absorption of U-100 (T-50% = 196.2 min). According to the simulation results, the absorption rate of monomeric analogues is not dependent on concentration. No significant chances of the absorption rate could also be observed by varying volume and injection depth of the monomeric analogues.

Computer Simulation↗
PubMed1990

Senescence in the skin.

No difference was found between groups of senescent subjects and younger adults in the control of skin temperature, heat radiation and transcutaneous oxygen pressure. Although capillary numbers decline in elderly skin, transcutaneous oxygen pressure at 43 degrees C in elderly skin is no lower than in young subjects. Topical tretinoin (0.05%) increases heat radiation from the skin, but there is no correlation with an improvement in superficial wrinkles. No conclusion is possible regarding the effects of topical tretinoin on transcutaneous oxygen diffusion due to a wide variability in results; sometimes it is increased and sometimes it is decreased. In different regions of the skin, such as the face and thigh, increased skin radiation and skin contact temperature are not associated with increased transcutaneous oxygen diffusion.

Adult↗
PubMed1990

[Diagnostic value of various laboratory parameters in acute pancreatitis].

In 427 samples of serum and urine, collected during their stay at hospital from 40 patients affected with acute pancreatitis, the sensitivity and the specifity of total amylase and lipase in serum, total amylase and pancreas isoamylase in urine, as well as the amylase-/creatinine clearance were determined. The pancreas isoamylase in serum was used as reference value. It appeared that the sensitivity of the lipase was next to that of the pancreas isoamylase in serum, even in limit ranges. Usually the lipase stayed pathological the longest and could therefore be used to identify in the best way even an easing-off pancreatitis. The diagnostic accuracy of the total amylase in serum and urine, of the pancreatic isoamylase in urine and of the amylase-/creatinine clearance was found to be obviously less reliable. The specifity of all examined tests was reduced in patients with renal insufficiency, liver disease, alcohol abuse and in patients with abdominal pains of non pancreatic origin. Concluding form our results and with regard to the expenditure of laboratory technique and to the time required by the methods of determination, we found that of all the examined parameters, the lipase was the most convenient for both emergency and routine diagnose of an acute pancreatitis.

Acute Disease↗
PubMed1989

[Borrelia burgdorferi, clinical aspects, cultivation and identification of the pathogen in erythema migrans in Berlin].

Among other manifestations, the following diseases caused by Borrelia burgdorferi in Europe are transmitted by ticks of the species ixodes ricinus: erythema migrans (EM), lymphadenosis benigna cutis (LBC), lymphocytic meningo-radiculitis (Bannwarth's syndrome), and acrodermatitis chronica atrophicans (ACA). We report on a female patient, who developed EM 10 days after a-tick bite in Berlin. Borrelia burgdorferi could be cultivated from a skin biopsy specimen taken from the periphery of the EM. The isolates were identified as Borrelia burgdorferi by indirect immunofluorescence using the monoclonal antibodies H 9724 and H 5332.

Animals↗
PubMed1989

[Diagnostic value of a diagnostic strip for determining urinary amylase].

The semiquantitative determination of amylase in urine with a stick-method has produced controversial results as to its diagnostical significance. In our study we compared the result of the Rapignost-test with the simultaneously measures activity of enzymes (total amylase, pancreatic isoamylase in serum and urine and lipase) in 323 samples of serum and urine taken from 32 patients affected with acute pancreatitis. On the 1st day of hospitalization Rapignost was positive in only 17 out of 32 cases. Both sensitivity and specificity of the test depended of the values referred to. Near range limits and in cases with slight or average increase of the enzymes, the correspondence of Rapignost results were unsatisfactory. We found a good correspondence in cases with normal low and excessively high values of the enzymes. On the whole, Rapignost showed the best correspondence with the pancreas isoamylase in urine. The result of Rapignost was also positive in 5 out of 15 cases with extrapancreatic increased urinary amylase, which confirms its lack of organ specificity. From case to case, the -, and + + test results of Rapignost did not lead to any conclusions as to the absolute values of the enzymes in serum and urine. Our results show that Rapignost does not offer enough safety either to confirm or to exclude an acute pancreatitis, and especially it should not be used as a screening test in emergency diagnostics. The determination of the enzyme, in particular in serum, can not be eluded.

Adult↗
PubMed1989

[Extrapancreatic hyperamylasemia. Diagnostic value of isoamylase and lipase determination].

The P- and S-isoamylase and lipase of 72 patients with extrapancreatic hyperamylasemia were determined and their diagnostic value checked to rule out a pancreatic origin. The hyperenzymemia was generally slight although extremely high values were observed in isolated cases. The increased serum amylase results were more often caused by P-, rather than S-isoamylase, while in 28% of cases lipase was also increased. In lung diseases, anorexia and disorders of the head organs only S-isoamylase was pathologically increased while P-isoamylase and lipase remained normal. In other entities such as liver, stomach and intestinal diseases, functional disorders, acidosis, infections, etc., the isoenzymes and lipase showed a variable tendency to increase. Thus, extrapancreatic hyperamylasemia could not always be identified by detection of isoamylases or with the aid of lipase determinations. Overall, however, lipase more often remained in the normal range and was therefore more useful than determination of the isoamylases in differentiating hyperenzymemia.

Acidosis↗
PubMed1989

Marginal zone of the murine spleen in autotransplants: functional and histological observations in the response against a thymus-independent type 2 antigen.

Splenic tissue from mice was autotransplanted; after initial necrosis, a rapid restoration of implants into a structure histologically indistinguishable from splenic tissue was observed. The development of the marginal zone in these autotransplants, as determined with monoclonal antibodies against different splenic cell types and routine histological stains, was compared with the local and systemic response against a thymus-independent (TI) type 2 antigen. Full restoration of time course and peak of anti-trinitrophenyl (TNP) serum titres against TNP-Ficoll was observed at 4 weeks after autotransplantation. Anti-TNP antibody-forming cells were observed in subnormal and normal numbers in 2- and 4-week old autotransplants, respectively. The appearance of normal numbers of antibody-forming cells, and the restoration of antibody titres at week 4 correlated with the return of newly formed B cells in a normal marginal zone. An unexpected observation was that marginal zone macrophages did not return until 10 weeks after transplantation, thereby making the necessity for these cells in the normal TI-2 response unlikely. We conclude that normal anti-TI-2 responses (onset and peak titres) can be restored by autotransplantation of splenic tissue. B cells and marginal zone organization are responsible for this response, for which marginal zone macrophages seem expendable. The partial protection against overwhelming post-splenectomy infections, given by autotransplants, can thus be explained by restorative capabilities of these implants on antigen presentation and antibody formation against TI-2 antigens, and not by an increase (compared with splenectomized individuals) of phagocytosis by marginal zone macrophages.

Animals↗
PubMed1988

[Streptococcus bovis bacteremia and colonic diseases].

Four febrile patients were found to have a bacteraemia or endocarditis caused by Streptococcus bovis. Although there were no gastrointestinal symptoms, polyps in the colon, of a high degree of malignancy, were discovered in three. In the fourth, carcinoma of the colon, requiring resection, was found seven years after Streptococcus bovis endocarditis. The polyps were removed by endoscopy and the Streptococcus bovis infection in all cases cured by penicillin. All four patients had accompanying resistance-lowering illnesses, which favoured microbial invasion.

Adenocarcinoma↗