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Biomedical subjects

A Buchner

Publications and source records attributed to A Buchner.

At least 37 records · Page 2Linked to original sources
PubMed2001

Auditory negative priming in speeded reactions and temporal order judgements.

Two experiments are reported that demonstrate negative priming for auditory stimuli. Reaction times and temporal order judgements were used as the dependent measures in Experiments 1 and 2, respectively. In Experiment 1, participants classified tones presented to one ear as wind or string instruments while ignoring tones presented to the other ear. The task was identical for both the prime and the subsequent probe presentations. Probe reactions were slower for previously ignored tones than for tones that had not occurred during the prime presentation. Probe reactions to previously attended tones were faster than reactions to nonrepeated tones. In Experiment 2, the probe reactions were replaced by temporal order judgements. The probability of accepting a tone as antecedent was lower for previously ignored primes than for new tones. No difference was observed between previously attended and new tones. The results are compatible with the conclusion that distractor inhibition is a necessary component of the processes that bring about observable negative priming phenomena.

Adolescent↗
PubMed2001

Lansoprazole treatment of patients with chronic idiopathic laryngitis: a placebo-controlled trial.

OBJECTIVE: Previous uncontrolled studies suggested a therapeutic benefit for treating gastroesophageal reflux disease (GERD) among patients with laryngitis. The present study is the first randomized, placebo-controlled, double-blind study of gastric acid suppression among patients with laryngitis in the United States. METHODS: Patients diagnosed with idiopathic chronic laryngitis were randomized to receive either lansoprazole 30 mg p.o. b.i.d. or a matching placebo for 3 months. Before randomization, all patients underwent upper endoscopy, dual probe ambulatory 24-h esophageal pH-metry, and laryngoscopy, as well as completing a symptom questionnaire for GERD and laryngitis. The primary outcome of treatment was the complete resolution of laryngeal symptoms. RESULTS: A total of 22 patients with symptoms and signs of chronic laryngitis were enrolled, 20 of whom completed the study. At baseline, there were no significant differences between the two groups with regards to GERD symptoms, erosive esophagitis, proximal and distal esophageal pH-metry, or laryngeal signs and symptoms. In an intention-to-treat analysis, six patients in the lansoprazole group (50%) and only one patient (10%) in the placebo group achieved a complete symptomatic response, p = 0.04. Apart from receiving lansoprazole, there were no significant differences between responders and nonresponders in any of baseline esophageal or laryngeal signs and symptoms. CONCLUSIONS: Empirical treatment with lansoprazole is efficacious in relieving symptoms of laryngitis compared to placebo. Such treatment can be considered as a first-line option in managing patients with idiopathic chronic laryngitis.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2001

Bulk and rhizosphere soil bacterial communities studied by denaturing gradient gel electrophoresis: plant-dependent enrichment and seasonal shifts revealed.

The bacterial rhizosphere communities of three host plants of the pathogenic fungus Verticillium dahliae, field-grown strawberry (Fragaria ananassa Duch.), oilseed rape (Brassica napus L.), and potato (Solanum tuberosum L.), were analyzed. We aimed to determine the degree to which the rhizosphere effect is plant dependent and whether this effect would be increased by growing the same crops in two consecutive years. Rhizosphere or soil samples were taken five times over the vegetation periods. To allow a cultivation-independent analysis, total community DNA was extracted from the microbial pellet recovered from root or soil samples. 16S rDNA fragments amplified by PCR from soil or rhizosphere bacterium DNA were analyzed by denaturing gradient gel electrophoresis (DGGE). The DGGE fingerprints showed plant-dependent shifts in the relative abundance of bacterial populations in the rhizosphere which became more pronounced in the second year. DGGE patterns of oilseed rape and potato rhizosphere communities were more similar to each other than to the strawberry patterns. In both years seasonal shifts in the abundance and composition of the bacterial rhizosphere populations were observed. Independent of the plant species, the patterns of the first sampling times for both years were characterized by the absence of some of the bands which became dominant at the following sampling times. Bacillus megaterium and Arthrobacter sp. were found as predominant populations in bulk soils. Sequencing of dominant bands excised from the rhizosphere patterns revealed that 6 out of 10 bands resembled gram-positive bacteria. Nocardia populations were identified as strawberry-specific bands.

Bacteria↗
PubMed2001

Lysis of prostate carcinoma cells by trifunctional bispecific antibodies (alpha EpCAM x alpha CD3).

Bispecific monoclonal antibodies (bsAbs) are a promising immunotherapeutic option for treatment of cancer, especially in situations of minimal residual disease. The combination of an anti-CD3 and anti-tumor-associated antigen antibody redirects cytotoxic T-lymphocytes towards malignant cells. Using a trifunctional bispecific antibody against EpCAM x CD3, that additionally activates Fc gamma R(+) accessory cells via its Fc region, we investigated the interaction between three EpCAM(+) prostate carcinoma cell lines and peripheral blood mononuclear cells (PBMCs) of healthy donors and patients with prostate carcinoma (PC). Visualization was performed by double immunocytochemical methods and computerized sequential video microscopy. Tumor cells and PBMCs supplemented with alpha EpCAM x alpha CD3 in 16-well chamber slides resulted in lysis of tumor cells within 1--3 days without any differences between patient and healthy donor PBMCs. The characteristic necrotic way of tumor cell killing (rounding, swelling, disrupting) could be observed in computerized sequences of video frames. Simultaneously, we could not reveal any form of apoptotic signal using three different apoptotic markers (TUNEL, M30 cyto death, anti-active caspase 3). Within the first 48 hr we observed typical PBMC cluster formation with increasing cell proliferation. PBMCs surrounding the tumor cells were not dominated by CD4(+), CD8(+), or CD14(+) cells. Lymphocytes with pore-forming perforin proteins concentrated towards the tumor target cells. Our combination of double immunocytochemical and computerized video microscopic techniques may serve as an important improvement of validity of cell-cell interaction experiments using in vitro models. (J Histochem Cytochem 49:911-917, 2001)

Antibodies, Bispecific↗
PubMed2001

[Development of an incubation system for an inverted microscopy for long-term observation of cell cultures using chamber slides].

Trifunctional bispecific antibodies open up new immunological possibilities in tumour treatment. Prior to clinical application, comprehensive investigations using animal models and in vitro examinations need to be done. To investigate long-term interactions between various immunologically active blood cells and individual tumour cells in the presence of antibodies, we developed an incubation system for experimental cell cultures on an inverted microscope. The system consists of a perspex box with a central moisture chamber with integrated water reservoir, external air circulation heating, and a CO2 supply. The sterile cell cultures are located in the wells of a slide positioned within a depression in the water reservoir. The newly developed incubation system enables continuous observation over the long term of experiments under optimal cell cultures conditions in combination with modern video techniques.

Antibodies, Bispecific↗
PubMed2000

On the reliability of implicit and explicit memory measures.

Functional dissociations between implicit and explicit memory tests often take the form of large differences between groups or experimental conditions (e.g., amnesics and controls, elderly and younger persons, or persons learning with and without a distracting secondary task) when performance is assessed using explicit memory tests, whereas no difference is observed with implicit memory tests. We argue that the interpretation of such dissociations in terms of the memory processes or systems involved in performance is problematic because the same data pattern would emerge as a result of a mere methodological artifact, that is, the situation that implicit memory tests have low reliability whereas explicit memory tests are fairly reliable measurement instruments. We present reasons for such a reliability difference, and we demonstrate it empirically in Experiments 1a, 1b, and 2. However, our analysis also shows, and Experiment 3 confirms empirically, that implicit memory tests need not necessarily be less reliable measurement instruments than explicit memory tests.

Adolescent↗
PubMed2000

Age-related histomorphometric changes in labial salivary glands with special reference to the acinar component.

PURPOSE: To evaluate histomorphometric age-related changes in labial salivary glands (LSG) of healthy subjects, with special reference to the mucous and seromucous acini. METHOD: Investigation of age-related histomorphometric changes was conducted on 120 samples of LSG obtained from autopsy subjects free of salivary gland tumors/diseases. Samples were divided into young (< 30 years, n = 30), adult (30-60 years, n = 45) and old (> 60 years, n = 45) age groups. Measurements were performed on hematoxylin and eosin stained slides. Parenchymal components included acini and ducts. The acinar component was presently analyzed separately in respect to mucous acinar cells and seromucous acinar cells. Mucous acinar cells presented pale eosinophilic cytoplasm, while that of the seromucous was darker and basophilic. Stromal components included connective tissue, blood and lymphatic vessels, inflammatory infiltrate and adipose tissue. The mean volume fraction (V(v)) of all components in each age group was calculated. Statistical analysis was performed by one-way ANOVA and Tamhane tests. RESULTS: The mean V(v) of the seromucous acinar cells decreased by 49.3% (p < 0.0001) and that of the mucous acinar cells decreased only by 28.5% (p = 0.0001). Changes in the ducts were statistically non-significant (p = 0.312). Of the stromal components, the mean V(v) of the adipose tissue showed the highest increase, 2768% (p < 0.0001) followed by the inflammatory infiltrate, 512% (p < 0.0001). CONCLUSIONS: The marked decrease in the V(v) of seromucous acinar cells accompanied by a lower decrease in the V(v) of mucous acinar cells may explain age-related changes in LSG secretion. These findings could bear important implications regarding functional age-related changes of these glands.

Adult↗
PubMed2000

Aging of human palatal salivary glands: a histomorphometric study.

The aim of the present study was to examine age-related changes in the parenchymal and stromal components of palatal salivary glands of healthy subjects. Palatal salivary gland biopsies were obtained from 120 autopsies and were divided into young, adult, and old age groups. Histomorphometric measurements were performed on hematoxylin and eosin (H&E) stained slides. Parenchymal components included acini and ducts, and stromal components included connective tissue, blood and lymphatic vessels, inflammatory infiltrate, and adipose tissue. The mean volume fraction of each component in each age group was calculated. Statistical analysis was performed by one-way ANOVA and Tamhane tests. The mean volume fraction of the acinar component demonstrated a significant age-related decrease of 48% (P < 0.001). The mean volume fractions of the ducts and of all the stromal components demonstrated a significant age-related increase (P < 0. 001). The inflammatory infiltrate component had the highest increase with aging (1471%), followed by the ducts (177%), blood and lymphatic vessels (138%), adipose tissue (130%), and connective tissue (60%). These age-related changes, the first to be reported in palatal salivary glands from healthy subjects, are different from those described in the labial salivary glands, especially in regard to the significant increase in the parenchymal ductal component, as well as in the stromal inflammatory infiltrate and adipose tissue components. It can be suggested that these changes could have important implications regarding the age-related function of these glands.

Adolescent↗
PubMed2000

Immunohistochemical evaluation of estrogen and progesterone receptors in adenoid cystic carcinoma of salivary gland origin.

Adenoid cystic carcinoma (ACC) is a malignant tumor of salivary gland origin, which is characterized by a high rate of local recurrence and distant metastasis even after aggressive surgical treatment. In several studies using various immunohistochemical techniques, estrogen and progesterone receptor (ER and PgR) proteins in salivary gland ACC have been identified and the possible use of endocrine therapy as a treatment modality suggested. On this basis, 27 samples of formalin-fixed paraffin-embedded salivary gland ACC were immunohistochemically evaluated for the presence of ER and PgR. ER was not detected in any of the tumors and PgR was identified in only two cases. Thus, application of hormone therapy to salivary gland ACC is not supported by the results of the present study.

Adult↗
PubMed2000

Gender stereotyping and decision processes: extending and reversing the gender bias in fame judgments.

M. R. Banaji and A. G. Greenwald (1995) demonstrated a gender bias in fame judgments--that is, an increase in judged fame due to prior processing that was larger for male than for female names. They suggested that participants shift criteria between judging men and women, using the more liberal criterion for judging men. This "criterion-shift" account appeared problematic for a number of reasons. In this article, 3 experiments are reported that were designed to evaluate the criterion-shift account of the gender bias in the false-fame effect against a distribution-shift account. The results were consistent with the criterion-shift account, and they helped to define more precisely the situations in which people may be ready to shift their response criterion on an item-by-item basis. In addition, the results were incompatible with an interpretation of the criterion shift as an artifact of the experimental situation in the experiments reported by M. R. Banaji and A. G. Greenwald.

Adult↗
PubMed2000

Successful strategy for the selection of new strawberry-associated rhizobacteria antagonistic to Verticillium wilt.

In order to isolate and characterize new strawberry-associated bacteria antagonistic to the soil-borne pathogenic fungus Verticillium dahliae Kleb., rhizobacterial populations from two different strawberry species, Greenish Strawberry (Fragaria viridis) and Garden Strawberry (F. x ananassa) obtained after plating onto King's B and glycerol-arginine agar, were screened for in vitro antagonism toward V. dahliae. The proportion of isolates with antifungal activity determined in in vitro assay against V. dahliae was higher for the Garden Strawberry than for the Greenish Strawberry. From 300 isolates, 20 isolates with strong antifungal activity were selected characterized by physiological profiling and molecular fingerprinting methods. Diversity among the isolates was characterized with molecular fingerprints using amplified ribosomal DNA restriction analysis (ARDRA) and the more discriminating BOX-PCR fingerprint method. The physiological profiles were well correlated with molecular fingerprinting pattern analysis. Significant reduction of Verticillium wilt by bacterial dipping bath treatment was shown in the greenhouse and in fields naturally infested by V. dahliae. The relative increase of yield ranged from 117% (Streptomyces albidoflavus S1) to 344% (Pseudomonas fluorescens P10) in greenhouse trials, and 113% (Streptomyces albidoflavus S1) to 247% (Pseudomonas fluorescens P6) in field trials. Evaluation resulted in the selection of three effective biocontrol agents (Pseudomonas fluorescens P6, P10, and Streptomyces diastatochromogenes S9) antagonistic to the Verticillium wilt pathogen.

Antibiosis↗
PubMed2000

Further evidence on the similarity of memory processes in the process dissociation procedure and in source monitoring.

Buchner, Erdfelder, Steffens, and Martensen (1997) proposed that the memory processes involved in recognition judgments in the process dissociation procedure are the same as those involved in standard source monitoring tasks. Two extensions of that research are presented here. First, following a line of reasoning recently brought forward by Jacoby (1998), the instructions in the earlier study could have triggered different processes from those triggered by his instructions. However, with instructions conforming as closely as possible to those reported by Jacoby (1991), Experiment 1 replicated the earlier recognition judgment finding almost perfectly. Second, the memory processes underlying fame judgments in the process dissociation procedure could also resemble those involved in source monitoring tasks. Indeed, the results of Experiment 2 are compatible with the hypothesis that the same processes are involved in fame judgments given a source monitoring or a process dissociation procedure.

Adult↗
PubMed1999

Lingual cyst with respiratory epithelium: an entity of debatable histogenesis.

PURPOSE: The purpose of this report was to describe a new case of lingual cyst with respiratory epithelium, to review and analyze the literature regarding lingual cyst of foregut origin and lingual alimentary cyst, and to discuss the suitable terminology for these uncommon cysts. MATERIAL AND METHODS: Data from articles published in the English language between the years 1942 and 1947 were used. RESULTS: The review of the literature showed 53 lingual cysts of which 29 could be grouped into lingual alimentary tract cysts and 24 into lingual cysts of foregut origin. There was an overlap in histologic and clinical features and embryogenesis of both cysts. CONCLUSIONS: Differentiation between both cysts cannot be supported, and until further information is accumulated it is suggested that histologic descriptive terms be used such as lingual cyst with respiratory epithelium, lingual cyst with gastric epithelium, or lingual cyst with respiratory and gastric epithelium.

Child↗
PubMed1999

Radiological and clinical features of aneurysmal bone cyst of the jaws.

PURPOSE: To evaluate the clinical and radiological features of aneurysmal bone cyst (ABC) of the jaws. MATERIALS AND METHODS: A total of 64 cases (60 from the English-language literature and four new cases) were studied and critically evaluated with emphasis on the radiological features. RESULTS: Age at time of initial diagnosis ranged from 4-78 years, with a mean age of 21.5 years and median age of 17 years. There were no differences in gender distribution. The ratio between the mandible and maxilla was 2.4:1. Ninety-two per cent of the lesions were located in the posterior region of the jaws. Lesions were radiolucent in 87% of cases, radiopaque in 2% and mixed in 11%. Fifty-three per cent were multilocular, 43% unilocular and 3% not loculated. The border of the lesions was defined but not corticated in 39%, well defined in 33% and diffuse in 28%. CONCLUSIONS: ABC has a variable radiological appearance and should be considered in the differential diagnosis of any unilocular or multilocular radiolucent lesion of the jaws as well as any mixed radiolucent-radiopaque lesion.

Adolescent↗
PubMed1999

Collagen fibres in the wall of odontogenic keratocysts: a study with picrosirius red and polarizing microscopy.

The collagen in the walls of 15 keratocysts was studied histochemically by staining sections with picrosirius red and examining them with polarizing microscopy. This was compared to 15 cases of dentigerous cyst and 15 cases of radicular cyst. Polarization colours of the collagen fibres were recorded according to their width. No differences were found between the polarization colours of thin fibres (<0.8 microm) in all three lesions; the polarization colours of thick fibres (1.6-2.4 microm) in keratocysts were significantly more greenish-yellow when compared with those of dentigerous cysts and radicular cysts. The staining of the collagen fibres in the keratocysts is similar to that reported in odontogenic neoplasms, which suggests that the stroma of keratocysts could be regarded not just as a structural support of the cyst wall, but as playing a part in the neoplastic behaviour of the cyst.

Analysis of Variance↗
PubMed1998

Ultrasonographic appearance of normal superficial cervical and subiliac lymph nodes in cattle.

The superficial cervical and the subiliac lymph nodes of 18 healthy, non-pregnant Simmental cows with a mean (sd) age of 5-6 (1.6) years were examined ultrasonographically in transverse and longitudinal planes with a real-time B-mode unit equipped with a 7.5 MHz linear-transducer. The position, demarcation and echogenicity of the lymph nodes were examined, and the craniocaudal and lateromedial diameters of each lymph node were measured three times within a period of six weeks. The pole to pole length of the lymph nodes was determined with a tape measure on the surface of the skin because the whole length could not be imaged in a single scan field. The gross anatomical and histological results showed that the lymph nodes were normal. Ultrasonographically, they were well demarcated from the adjoining muscular and subcutaneous tissue. Their internal structure was characterised by an anechoic to hypoechoic cortical zone corresponding to the lymphoid tissue, and an echogenic medullary zone, where the lymphatic sinuses converge towards the hilus and produce numerous acoustic interfaces. In all the lymph nodes, the hilar area had an echoic to hyperechoic appearance. The mean (sd) pole to pole length of the superficial cervical lymph nodes was 15.5 (3.2) cm and of the subiliac lymph nodes 13.5 (2.4) cm. The mean craniocaudal and lateromedial diameters of the superficial cervical lymph nodes were 2.8 (0.3) cm and 1.6 (0.3) cm, and those of the subiliac lymph nodes were 2.4 (0.4) cm and 1.1 (0.3) cm. The ultrasonographic morphology of these normal lymph nodes was consistent and provides basic reference data for the investigation of lymphadenopathies in cattle.

Animals↗
PubMed1998

Lingual osteoma: a debatable entity.

PURPOSE: This article analyzes osseous lesions in the tongue with regard to the clinical and histologic features and discusses the pathogenesis and terminology of these lesions. MATERIALS AND METHODS: Thirty-eight cases of lingual osseous lesions were retrieved from the English language literature, and two new cases were added. RESULTS: The lesions had a female predilection, with a female-to-male ratio of 2.3:1. Mean age of the patients at time of diagnosis was 31.4 years. The lesions were located in the posterior third of the dorsum of the tongue in 67.5% of the cases, in the lateral margins in 25%, and in the mid-third of the tongue in 7.5%. Size ranged from 0.5 to 5.0 cm. Duration of the lesions ranged from several months to 50 years. In eight cases, there was information that the lesions had increased in size. Histologically, the lesions appeared a well-circumscribed mass of vital bone under the surface epithelium. The two new cases, when examined by polarized light, showed a mixture of woven and mature bone. CONCLUSION: The osseous lesions of the tongue represent a heterogeneous group of lesions in which some may represent a developmental malformation, and others may be a reactive lesion after trauma or irritation. Some lesions behave as true neoplasms and others as choristomas. It is suggested that the descriptive term "osseous tumorlike lesion of the tongue" may be more appropriate for this group.

Adult↗