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J Winkler

Publications and source records attributed to J Winkler.

At least 55 records · Page 3Linked to original sources
PubMed2002

[Invasive pulmonary aspergillosis--CT findings in context with the clinical course].

PURPOSE: To investigate the impact of chest radiographs and CT in patients suffering from invasive pulmonary aspergillosis (IPA) compared to the clinical course. PATIENTS AND METHODS: Twenty-three patients with confirmed diagnosis of IPA between January 1996 and September 1999 were included in this study. Signs of inflammatory infiltrates on chest radiographs and CT were retrospectively evaluated in relation to the onset of the clinical symptoms. Infiltrates on CT were analyzed in detail with respect to number, morphology, and localization. RESULTS: Seventy-six infiltrates were found on the CT of 22 patients; one patient had diffuse areas of lung infiltrates. Both lungs were affected by infiltrates in 14 patients. Pleural effusions were confirmed in 12 patients. Twelve patients had typically round foci with halo and nine patients crescent air signs. The preferred localization of lung infiltrates was segment 6. The median interval between the onset of clinical symptoms and the first radiographic changes was 5.5 days, with an additional interval of 4.5 days until confirmation by CT. Localization, number of infiltrates, and clinical course were not related. CONCLUSION: In immune-compromised patients with fever, a CT of the chest should be carried out as soon as possible to detect signs indicative of IPA. Morphological changes on CT like a round focus with halo and crescent air sign support the diagnosis of IPA. In this context, special attention should be directed to pulmonary segment 6.

Aspergillosis↗
PubMed2002

Peripheral airway obstruction in primary pulmonary hypertension.

BACKGROUND: As there is controversy about changes in lung function in primary pulmonary hypertension (PPH), lung mechanics were assessed with a focus on expiratory airflow in relation to pulmonary haemodynamics. METHODS: A cross sectional study was performed in 64 controls and 171 patients with PPH (117 women) of mean (SD) age 45 (13) years, pulmonary artery pressure (PAPmean) 57 (15) mm Hg, and pulmonary vascular resistance 1371 (644) dyne.s/cm(5). RESULTS: Mean (SD) total lung capacity was similar in patients with PPH and controls (98 (12)% predicted v 102 (17)% predicted, mean difference -4 (95% confidence interval (CI) -7.89 to -0.11); residual volume (RV) was increased (118 (24)% predicted v 109 (27)% predicted, mean difference 9 (95% CI 1.86 to 16.14); and vital capacity (VC) was decreased (91 (16)% predicted v 102 (10)% predicted, mean difference -11 (95% CI 15.19 to -6.80). RV/TLC was increased (117 (27)% predicted v 97 (29)% predicted, mean difference 20 (95% CI 12.3 to 27.8)) and correlated with PAPmean (r=0.31, p<0.001). In patients with PAPmean above the median of 56 mm Hg, RV/TLC was further increased (125 (32)% predicted v 111 (22)% predicted, mean difference -14 (95% CI -22.2 to -5.8)). Expiratory flow-volume curves were reduced and curvilinear in patients with PPH. CONCLUSIONS: Peripheral airway obstruction is common in PPH and is more pronounced in severe disease. This may contribute to symptoms. Reversibility of bronchodilation and relation to exercise capacity need further evaluation.

Airway Obstruction↗
PubMed2002

The health-promoting behaviors and attitude towards menopause and hormone replacement therapy among women on dialysis.

The aim of this study was to assess the health-related behaviors, knowledge and attitude towards menopause and hormone replacement therapy (HRT) among women receiving dialysis treatment. The study population consisted of 44 women aged 55-75 years attending the dialysis unit. All women completed a 20-item questionnaire, which covered information on personal health-care habits, life style and attitude regarding menopause and HRT. The majority of participants were of desirable weight (body mass index < 25 kg/m2) and had a positive body image. About 80% had never smoked, and did not engage in regular physical activity. Over half underwent annual Pap smear, mammography, breast examination by a physician, and only a small minority performed breast self-examination. Surprisingly, 45% had used HRT in the past, but only 5% were current users. Although we expected postmenopausal women with a life-threatening disease to be more aware of personal health care than the general population, only a relatively small percentage of the study population safeguarded their health care, and used HRT. Stronger educational efforts may be needed to promote health-related behaviors and a positive attitude to health care, aging and menopause in this subgroup of patients.

Aged↗
PubMed2001

Quantitative distribution of glycosaminoglycans in young and senile (cataractous) anterior lens capsules.

The ocular lens is surrounded by the lens capsule, which is an elastic and unusually thick basal membrane. Anionic sites are thought to be responsible for charge-selective permeability barriers in basal membranes. We have used cationic colloidal gold as a tracer for anionic binding sites to investigate the distribution of glycosaminoglycans in young and senile (cataractous) lens capsules. Using electron microscopy, combined with the cationic colloidal gold post-embedding technique, glycosaminoglycans were localized distinctively in a continuous layer immediately apposed to the lens epithelium, which has been referred to as the lamina lucida. The amount of gold particles decreased from the internal (lenticular) side of the capsule, toward the center, followed by an increase of label intensity toward the external (humoral) side. The humoral surface is characterized by a highly anionic layer measuring 1.5--4 micro m. Immunofluorescence microscopy localized three main types of glycosaminoglycans (heparan-, chondroitin- and dermatan sulfate) within this distinctive layer. Quantitative electron microscopy demonstrated reduced amounts of glycosaminoglycans at the lenticular and humoral side of senile (cataractous) lens capsules. The distinctive spatial distribution of glycosaminoglycans in human lens capsules is discussed in terms of age-related structural and functional changes.

Adult↗
PubMed2001

Time-related changes of collected shed blood in autologous retransfusion after total knee arthroplasty.

A prospective study was done to determine the changes in blood quality parameters of collected drainage blood in retransfusion systems at 6 and 12 h after surgery to verify whether the blood was still suitable for retransfusion purposes for an additional 6 postoperative hours beyond the so far accepted first 6-h time window after surgery. Eighty-one patients received retransfusion within the first 6 h immediately following total knee arthroplasty. Additionally, drainage blood was collected for another 6 h using the same retransfusion system. Samples for laboratory analysis were taken from both the first and second 6-h blood collection interval. Hemoglobin values increased from 9.6 to 10.4 g dl(-1) (p = 0.021). Platelet counts increased from 65,500 to 80,900 microl(-1) (p < 0.001). Leukocyte counts increased from 5,550 to 8,190 1(-1) (p < 0.001). Lactate dehydrogenase (672 U l(-1) during the first vs 651 U l(-1) during the second collection period) and free hemoglobin (71.7 mg dl(-1) vs 67.0 mg dl(-1)) did not change significantly. The potassium concentration decreased slightly from 4.33 to 4.20 mg dl(-1) (p = 0.002). The lactate concentration increased from 4.44 to 7.21 mg dl(-1) (p < 0.001). The pH decreased from 7.07 to 6.94 (p < 0.001). Interleukin-6 concentration increased from 6,500 to 46,500 ng l(-1) (p < 0.001). In this study, we found no relevant difference in most of the drainage blood quality parameters between the first 6-h collection period and the second 6-h collection with regard to its suitability for autologous retransfusion except higher interleukin-6 levels. Due to the higher interleukin concentration, a possible increase in febrile reactions should be taken into account during retransfusion.

Aged↗
PubMed2001

Immunohistochemical and charge-specific localization of anionic constituents in pseudoexfoliation deposits on the central anterior lens capsule from individuals with pseudoexfoliation syndrome.

BACKGROUND: Pseudoexfoliation (PSX) syndrome is a degenerative systemic disorder that is characterized primarily by deposits of distinct fibrillar material on the surface lining the anterior and posterior chambers of the eye and is often associated with cataract and glaucoma. Although some components of the PSX material have been identified, the precise composition is obscure. METHODS: High-resolution scanning electron microscopy in conjunction with colloidal cationic gold labeling was used to localize anionic constituents at the surface of PSX aggregates. Transmission electron microscopy was applied for the immunocytochemical detection of glycosaminoglycans, and to monitor the charge-specific distribution of colloidal thorium dioxide and ferritin in PSX material. The specific binding of antibodies was confirmed by immunohistological staining of paraffin-embedded specimens. RESULTS: Paraffin-embedded tissue sections revealed immunoreactivity for keratan sulfate and dermatan sulfate proteoglycan within PSX material deposited on the surface of the anterior lens capsule. Post-embedding immunogold labeling of keratan sulfate demonstrated an intense label of PSX aggregates primarily associated with mature PSX fibrils, whereas dermatan sulfate proteoglycon appeared to be present in low quantities. Additionally, keratan sulfate was found at the humoral periphery of the lens capsules. To further investigate the distribution of anionic sites in PSX material, we used cationic colloidal tracers of different size, such as gold, thorium dioxide and ferritin. PSX aggregates exhibited a strong negative charge, resulting very likely from glycosaminoglycan chains of proteoglycans. The density of anionic sites was higher at the interfibrillar matrix. Lens capsules associated with PSX material revealed a diminished accumulation of cationic ferritin at the humoral surfaces. CONCLUSIONS: Increased amounts of different glycosaminoglycans identified in PSX material suggest an important role of proteoglycans for the pathogenic pathway in PSX.

Aged↗
PubMed2001

Neurobiology.

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Journal Article↗
PubMed2001

Neurobiology.

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Animals↗
PubMed2001

Aspergillus detection in bronchoscopically acquired material. Significance and interpretation.

Pulmonary invasive aspergillosis is frequently difficult to diagnose. In particular, the value of the cultivation of Aspergillus and the Aspergillus galactomannan antigen detection (Pastorex) in bronchoscopically acquired material (bronchoalveolar lavage = BAL, bronchial lavage = BL) in the course of diagnosing this mycosis is viewed controversially. Between January 1996 and September 1999, we obtained 114 positive results in 100 bronchoscopically aquired specimens from a total of 69 patients. 59 of the 69 patients were immunosuppressed, 42 suffered from pulmonary aspergillosis and 38 suffered from invasive pulmonary aspergillosis. The positive prediction rate for a positive result with regard to pulmonary aspergillosis in bronchoscopically acquired material was approximately 61%. Cultivation of Aspergillus was more successful in BAL, and the Aspergillus antigen detection was more successful in BL.

Antigens, Fungal↗
PubMed2001

Factors influencing breath condensate volume.

Analysis of breath condensate (BC) has received interest recently due to the need for easy and repetitive monitoring or airway and pulmonary disease. While many authors have used custom built systems, commercial systems are now available and will probably be used more widely. Early studies of markers and mediators in BC have reported concentrations following varying periods of sampling time. However, factors that influence the generation of BC have not been analysed and it is unclear whether breathing rate, tidal volume, lung function, body weight, height or age influence the amount of BC collected. We therefore studied the influence of these factors on breath condensate volume and breath condensate urea and protein concentrations in 22 healthy volunteers and 23 COPD patients. A strong correlation of total respired volume and breath condensate volume was observed for both groups (volunteers: r=0.952, p < 0.0001, COPD: r=0.883, p < 0.001) while no significant correlation existed for breath condensate volume and TLC, RV, Vc, FEV1, R(tot), height or body weight, As long as ventilation remained fairly constant, breath condensate volume increased linearly with time. The fraction of breath condensate extracted from total vapour contained in the exhalate was estimated by measuring relative atmospheric humidity before and after the collecting tube. The amount calculated by the change in temperature and saturation corresponded closely to the amount actually collected. We conclude from these results that breath condensate volume is primarily dependent on V(E), and does not seem to depend on lung function parameters. For standardisation it is suggested to report breath condensate measurements per volume respired. Both, urea and protein are present in measurable quantities in breath condensate and protein as well as BCV may be helpful denominators for comparison with e.g. cytokines in lung disease.

Asthma↗
PubMed2001

3-Dimensional organization of the N-terminal vinculin head fragment.

The cytoskeleton-associated protein vinculin is composed of a globular head and an elongated tail domain. The protein can be cleaved by V8 protease treatment into two fragments with apparent molecular masses of 90 and 29/27 kDa, respectively. So far, no high-resolution data on the tertiary structure of the N-terminal 90-kDa fragment are available. We analyzed the 90-kDa fragment in detail, using electron spectroscopic imaging in conjunction with modelling experiments. The front view projection of this fragment appears roughly rhomboidal, with 4 intensity maxima arranged at the vertices and a stain-filled region in the center. Based on a detailed examination of different particle projections, a 3-dimensional model was constructed which appears as a flattened tetrahedron. A comparison of the 90-kDa fragment with the intact protein allows for a correlation between the subdomain organization of the vinculin head and the biochemically defined V8 protease cleavage sites (aa 851 and 857).

Animals↗
PubMed2001

Increased interleukin-6 in collected drainage blood after total knee arthroplasty: an association with febrile reactions during retransfusion.

We determined interleukin-6 (IL-6) concentrations in collected shed drainage blood intended for retransfusion in a prospective study in 81 patients after total knee replacement. We found large increases in IL-6 levels, averaging 6.5 (SD 3.9) ng/mL, in shed blood collected in the first 6 postoperative hours. 3 patients had febrile reactions after collected blood was retransfused. The IL-6 levels in the drainage blood of these patients were very high (9.6-13.4 ng/mL). In the blood collected after 6 hours, IL-6 concentrations increased to 47 (SD 33) ng/mL (p < 0.001). These results suggest a relation between increased interleukin-6 concentrations in shed drainage blood and the occurrence of febrile reactions after retransfusion of such blood.

Aged↗
PubMed2001

Photodynamics of the bacteriochlorophyll-carotenoid system. 1. Bacteriochlorophyll-photosensitized oxygenation of beta-carotene in acetone.

Carotenoids are well-known physical quenchers of chlorophyll excited states and reactive oxygen species both in vivo and in vitro. They may also be involved in chemical quenching undergoing, e.g. isomerizations or oxidations. We have found that beta-carotene (Car) in aerobic acetone is rapidly oxygenated under strong illumination with red light (lambda exc > or = 630 nm) in the presence of bacteriopheophytin a. At the same time the photosensitizer undergoes only slight (< 10%) photodegradation. By preparative high-performance liquid chromatography as many as seven major products of oxygen attachment to Car have been isolated. Their molecular masses show that Car sequentially accumulates up to six oxygen atoms while its C40-skeleton remains intact.

Acetone↗
PubMed2001

Molecular mechanisms of neuronal migration disorders, quo vadis?

Following terminal mitosis, neuronal precursor cells leave their site of origin and migrate towards their definitive site of residency. In order to establish the intricate cytoarchitecture described in the adult human brain, neuronal migration must be finely regulated. In humans, brain malformations can result from neuronal migration defects. The spectrum of migration disorder severity extends from few heterotopic neurons, as observed in periventricular heterotopia, to a complete cortical disorganization, as observed in cases of lissencephaly. Recently, specific migration disorders have been linked to mutations/deletions in the doublecortin, filamin-1, LIS1 and reelin genes. These proteins act at different levels of the signaling cascades transducing extracellular guiding cues into cytoskeletal reorganization. Here, we summarize the data concerning these four molecules and speculate on their functions and interaction partners during neuronal development.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMed2001

Ultrastructure and composition of asteroid bodies.

PURPOSE: Asteroid hyalosis is a disease of the vitreous, characterized by brilliant reflecting particles, termed asteroid bodies, which are surrounded by a tightly adhering network of fibrils. The composition and mode of formation of asteroid bodies is not yet understood in detail. The purpose of this study was to investigate the ultrastructure of asteroid bodies and to identify the intrinsic inorganic and organic components that contribute to the nature and development of asteroid bodies. METHODS: Electron energy loss spectroscopy and energy-filtered transmission electron microscopy were used for the elemental analysis of asteroid bodies. The ultrastructural localization of glycosaminoglycans was investigated, using lectin and antibody conjugates in conjunction with transmission electron microscopy and epifluorescence microscopy. Anionic sites of glycosaminoglycans were detected with 15 nm cationic colloidal gold at low pH, applied as a postembedding technique. Ultrastructural details of asteroid bodies were documented using fast Fourier transform analysis of zero-loss filtered images. RESULTS: Element mapping of asteroid bodies by electron spectroscopic imaging revealed a homogeneous distribution of calcium, phosphorus, and oxygen. The electron energy loss spectra of these elements showed details similar to those found for hydroxyapatite. Additionally, high contrast and sensitivity against a calcium-specific chelator highlighted the crystalline, apatite-like nature of asteroid bodies. Immunofluorescence microscopy revealed the presence of chondroitin-6-sulfate at the periphery of asteroid bodies, which is in agreement with the ultrastructural colocalization of anionic sites. Fast Fourier transform analysis revealed that each 7-nm periodicity of asteroid lamellar stacks is divided by a fine, parallel-oriented line, separating each 7-nm layer into two halves of 3.5-nm thickness. Carbohydrates specific for hyaluronic acid were observed by lectin-gold labeling to be part of the inner matrix of asteroid bodies. CONCLUSIONS: The results of this study demonstrate the structural and elemental similarity of asteroid bodies with hydroxyapatite. Proteoglycans and their glycosaminoglycan side chains are implicated in playing a role in regulating the biomineralization process.

Aged↗
PubMed2000

Analysis of neurogenesis and programmed cell death reveals a self-renewing capacity in the adult rat brain.

The adult central nervous system was thought to be very limited in its regenerative potential; however, the discovery that stem cell populations produce neurons in the adult brain highlights the dynamics of a previously assumed 'static' organ. The continuous generation of new neurons in the adult brain, nevertheless, leads to the question of whether neurogenesis is counterbalanced by an accompanying cell death in the same regions. The objective of this study was to stereologically analyze neurogenesis and programmed cell death in adult brain regions with known neurogenic activity. Using bromodeoxyuridine (BrdU) to identify newborn cells we find that within a few days of BrdU-labeling the adult dentate gyrus and olfactory bulb generate high numbers of newborn neurons. More importantly, dUTP-nick end labeling (TUNEL) reveals that areas of adult neurogenesis also contain high numbers of apoptotic cells. We conclude that programmed cell death may have an important regulatory function by eliminating supernumerous cells from neurogenic regions and may thus contribute to a self-renewal mechanism in the adult mammalian brain.

Animals↗
PubMed2000

Titania as a sorbent in normal-phase liquid chromatography.

"Sachtopore" a titanium dioxide sorbent for HPLC is compared to a silica, an alumina and a zirconia sorbent with regard to its physical and chemical properties and examples for chromatographic separations are given. Titania has hydroxyl groups on its surface that are only slightly acidic so that native titania can be used to separate basic molecules under normal-phase conditions. It is shown that this enables the purification of basic fine chemicals and pharmaceuticals. Also, a number of examples for the separation of non-basic isomeric substances mixtures are presented.

Amitriptyline↗