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S Loos

Publications and source records attributed to S Loos.

17 recordsLinked to original sources
PubMed2006

Role of yeast proliferation in the quality degradation of strawberries during refrigerated storage.

Quality changes of strawberries during storage can be caused both by microbiological and physiological processes. There is little known about the possible contribution of microbiological processes to the quality degradation of strawberries. In this study, quality of strawberries during storage was evaluated by analytical and sensorial analyses. It was the aim to investigate the influence of microbiological activity on the changes of different quality factors of strawberries during storage. During storage at 7 degrees C, quality was mainly determined by the odor and by visual defects. Regarding the odor, highly microbiologically contaminated late-season strawberries packaged in air at 7 degrees C became sensorially unacceptable due to the presence of high amounts of ethyl acetate. This could be attributed to the yeast proliferation: at yeast concentrations above 5.0 log cfu/g, an increase in ethanol was detected in the headspace of the strawberries. It was shown that ethanol was converted to ethyl acetate by strawberries resulting in an unacceptable odor. In an experiment with low microbiologically contaminated early-season strawberries, not reaching the above mentioned yeast counts, less ethyl acetate was detected which resulted in strawberries that were sensorially acceptable during the whole storage period (12 days). Strawberries packaged in modified atmosphere conditions showed a different quality pattern due to the effect of decreased O2-concentrations on both microbiological and physiological processes. This paper demonstrates that also microbiological processes on strawberries should be considered as they could play an important role in the sensorial quality when interacting with physiological processes.

Acetates↗
PubMed2006

[Patient satisfaction and geriatric care - an empirical study].

Patients' satisfaction has become a central concept in quality assurance. Despite progress in research in this area is still a lack of data for geriatric patients. Referring to the consumer model, satisfaction can be described as a difference between expectations and assessed performance. The aim of this study is to analyze satisfaction among geriatric patients in an in-patient setting. A personal interview was performed 1-2 days before discharge. Patients suffering for dementia or with problems to communicate were excluded. 124 of 268 geriatric patients who were discharged in 2003 were included (inclusion rate 46.3%). 119 were willing to participate (response rate 96.0%). Respondents were between 61 and 96 years old, 39% were male and 42% had serious functional limitations at time of admission. Multiple linear regression analysis revealed three significant predictors of a combined index of satisfaction and expectations: a) quality of hotel services; b) experience of neglect; c) provision of medical information and skills. In summary, standardized personal questionnaires can provide valid and reliable data of geriatric patients. Satisfaction of elderly patients is negatively affected by neglect and positively influenced by provision of medical information and a good hotel services.

Aged↗
PubMed2006

Metabolite production of yeasts on a strawberry-agar during storage at 7 degrees C in air and low oxygen atmosphere.

Changes of different quality factors of strawberries have been described until now from a physiological point of view. Possible effects on quality caused by yeast proliferation have not been described. To elucidate the metabolic activity of yeasts (i.e. Debaryomyces melissophilus, Rhodotorula glutinis, Cryptococcus laurentii), isolated from strawberries, they were inoculated on a simulation medium of strawberries (strawberry-agar). Their activity was measured by analysing and correlating microbiological counts, metabolite concentration in the headspace as well as in the medium, and sugar consumption. The isolated yeasts from strawberries could grow on the strawberry-agar, both under air conditions and modified atmosphere (MA) conditions. The maximum count for the yeasts reached 7.5-8.5 log cfu cm(-2) (air conditions) and 5.6-6.4 log cfu cm(-2) (MA conditions). Production or consumption of a number of compounds could be detected when microbial counts reached levels between 4.7 log cfu cm(-2) and 8.5 log cfu cm(-2) depending on species and atmospheric conditions. A range of volatile organic compounds, produced by the yeasts, was detected: acetone, ethyl acetate, ethanol, isopropyl acetate, ethyl butyrate, 1-propanol, 2-methyl-1-propanol, 1-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 1-hexanol and hexyl acetate. These compounds are able to influence the sensory properties of strawberries. A simultaneous decrease in sugar concentrations (sucrose, glucose, fructose) was observed. When ethanol reached high concentrations, ethyl acetate and ethyl butyrate were produced. This production can be attributed to a detoxification of ethanol by yeasts. The fermentative metabolism of yeasts during aerobic conditions could be explained by the Crabtree effect. As the detected volatile organic compounds produced by yeasts are also found in fresh strawberries, it can be concluded that these compounds are produced both by microbiological and physiological processes.

Colony Count, Microbial↗
PubMed2001

[Geriatric care in Germany--results of an empirical study].

BACKGROUND: In Germany, the situation of geriatric medicine has improved significantly over the past few years. Until now, though, there was little information available on the structure of the clinical geriatric departments. Since this information is vital to assess whether these departments can provide high-quality services, the German Federal Association of Clinical Geriatric Departments conducted a survey among its members. The goal was to gain deeper insight into the structure of the geriatric acute hospitals and rehabilitation units. METHODS: In 1999, member institutions were mailed a standardized questionnaire and all institutions (100%) returned the questionnaire to the association's central office. To increase data quality, data were screened and reports were generated for each institution. These reports were returned to the institutions which were asked to verify them. RESULTS: This article shows that in 1998 acute geriatric hospitals (n = 89), rehabilitation units (n = 52), acute day clinics (n = 45) and rehabilitation day clinics (n = 26) had--on average--60/60/15.3/14 beds/places and 828.15/677.3/164.2/125.9 patients. Occupancy rates averaged out at 88.7%/84.3%/86.4%/63.7% and daily hospital rates at DM 401.4/322.4/293.8/243.2. Basically, all geriatric institutions included in this survey had a multi-professional geriatric team. Patient-to-staff ratios for psychologists, social workers, ergo-, physio- and speech therapists were better in day clinics than in in-patient clinics and better in rehabilitation units than in acute hospitals. Geriatric institutions mainly focused on the treatment of neurological deficits. Most patients were admitted from other hospitals and discharged to their private residence. CONCLUSIONS: The results of this survey indicate that especially the acute hospitals are often not sufficiently staffed. Moreover, further efforts are necessary to clarify the indications for and modalities of geriatric day clinic treatment and rehabilitation. The data also show that a categorical distinction between geriatric acute hospitals and rehabilitation units is not possible. However, further data collection and more detailed analyses are needed.

Aged↗
PubMed2001

Serum withdrawal induces a redistribution of intracellular gelsolin towards F-actin in NIH 3T3 fibroblasts preceding apoptotic cell death.

The intracellular distribution of gelsolin in NIH 3T3 cells was examined by immunostaining using affinity-purified polyclonal gelsolin antibodies before and after induction of apoptosis by serum withdrawal. Serum deprivation induced detachment of an increasing number of NIH 3T3 cells, but also apoptosis in attached cells as verified morphologically by chromatin condensation, nuclear fragmentation and labelling of their periphery by FITC-annexin V. Ongoing apoptosis was also demonstrated by activation of caspase-3 activity and chromatin cleavage into high-molecular-mass fragments, although no internucleosomal chromatin degradation (DNA-ladder formation) was detected. When cells were maintained in the presence of 10% foetal calf serum, gelsolin immunoreactivity was evenly distributed in the cytoplasm. No obvious co-localisation of gelsolin and the actin-containing stress fibres was detected under these conditions. At day one after serum withdrawal, a redistribution of gelsolin to actin filaments was detected within a few attached cells by double fluorescence staining. The number of cells exhibiting this redistribution increased at days two to four. In addition, the stress fibres increased in thickness and their length was continuously reduced. At day four, many cells contained shortened stress fibres, which had lost their longitudinal orientation. Additionally, the cytoplasm of a number of attached cells was highly condensed around their nuclei and a homogenous distribution of both gelsolin and actin was detected in the remaining cytoplasmic rim. Up to day two, these effects were reversible after re-addition of serum to attached cells. A similar redistribution of gelsolin immunore-activity was observed after induction of apoptosis by cycloheximide, but not after initiation of necrosis by hydrogen peroxide. In NIH 3T3 cells no alteration in the expression of gelsolin at the level of protein (Western blot) or specific mRNA (Northern blot) was observed after serum withdrawal. Using Western blotting, no proteolysis of gelsolin was detected up to day 4, although caspase-3 activity was found to have increased fivefold after serum withdrawal. These results suggested that in these cells F-actin severing might occur in the absence or advance of gelsolin cleavage by caspases. Intact gelsolin on its own may be sufficient for the dissolution of the microfilaments, since micro-injection of gelsolin into primary bovine lens cells led to a transient disappearance of the stress fibres and to a reduction of their attachment area to the substratum. In NIH 3T3 cells similar effects of micro-injected gelsolin were only observed at day one after serum withdrawal.

3T3 Cells↗
PubMed2000

Cell differentiation and matrix gene expression in mesenchymal chondrosarcomas.

Mesenchymal chondrosarcomas are small-cell malignancies named as chondrosarcomas due to the focal appearance of cartilage islands. In this study, the use of in situ detection techniques on a large series of mesenchymal chondrosarcoma specimens allowed the identification of tumor-cell differentiation pathways in these neoplasms. We were able to trace all steps of chondrogenesis within mesenchymal chondrosarcoma by using characteristic marker genes of chondrocytic development. Starting from undifferentiated cells, which were negative for vimentin and any other mesenchymal marker, a substantial portion of the cellular (undifferentiated) tumor areas showed a chondroprogenitor phenotype with an onset of expression of vimentin and collagen type IIA. Cells in the chondroid areas showed the full expression panel of mature chondrocytes including type X collagen indicating focal hypertrophic differentiation of the neoplastic chondrocytes. Finally, evidence was found for transdifferentiation of the neoplastic chondrocytes to osteoblast-like cells in areas of neoplastic bone formation. These results establish mesenchymal chondrosarcoma as the very neoplasm of differentiating premesenchymal chondroprogenitor cells. The potential of neoplastic bone formation in mesenchymal chondrosarcoma introduces a new concept of neoplastic (chondrocytic) osteogenesis in musculoskeletal malignant neoplasms, which qualifies the old dogma that neoplastic bone/osteoid formation automatically implies the diagnosis of osteosarcoma.

Apoptosis↗
PubMed2000

Stereotactic breast biopsy: recumbent biopsy using add-on upright equipment.

OBJECTIVE: The purpose of the study was to show that stereotactic breast biopsy can be performed effectively and accurately using add-on stereotactic equipment when it is performed with the patient in a decubitus or recumbent position. MATERIALS AND METHODS: We retrospectively reviewed the results of 225 stereotactic core breast biopsies performed during a 42-month period. The biopsies were performed using a reclining mammography chair and add-on stereotactic equipment. Procedures were performed with the patient in the right or left lateral decubitus position or upright. Patients with benign biopsy results were followed up mammographically at 6 months initially, then yearly. RESULTS: Of the 225 lesions biopsied stereotactically, 205 lesions (91%) were biopsied with the patient in the decubitus (right or left) position and 20 (9%) biopsied with the patient upright. Pathology results were classified as abnormal in 45 lesions (20%) and normal in 180 lesions (80%). All but one of the abnormal lesions were followed up with surgical excision. One hundred thirty-four of the 180 benign lesions have been followed up with at least one 6-month mammogram (follow-up range, 6-40 months), and none of the lesions has been subsequently proven malignant. CONCLUSION: Stereotactic core biopsy can be performed effectively and accurately using standard add-on equipment when it is performed with the patient in the decubitus position. This approach obviates the use of dedicated prone stereotactic equipment.

Biopsy, Needle↗
PubMed1999

Chondroblastoma is an osteoid-forming, but not cartilage-forming neoplasm.

Chondroblastoma is defined as a 'benign tumour, characterized by highly cellular and relatively undifferentiated tissue composed of rounded or polygonal chondroblast-like cells' and the 'presence of cartilaginous intercellular matrix' (WHO). An extensive analysis of the extracellular matrix composition and gene expression pattern of a large series of chondroblastoma cases shows, however, that type II collagen, which is the main component of any cartilage matrix, is not expressed by the neoplastic cells of this tumour entity and is not deposited into the extracellular tumour matrix. Instead, osteoid and fibrous matrix is formed, with its typical biochemical composition. The multifocal expression of aggrecan proteoglycan in most chondroblastomas explains the bluish, pseudo-chondroid appearance of some of the matrix-rich areas of chondroblastomas. This study did not show chondroid matrix formation or chondroblastic cell differentiation in chondroblastomas, suggesting that chondroblastoma should be classified as a specific bone-forming, rather than cartilage-forming neoplasm.

Aggrecans↗
PubMed1999

Regulation of GCDFP-15 expression in human mammary cancer cells.

Gross cystic disease fluid protein 15 (GCDFP-15) is a major protein component of benign breast gross cysts. It is also found in approximately 50% of all breast cancer specimens. Androgen receptor (AR) mediated regulation of GCDFP-15 expression was investigated in the AR-positive human mammary cancer cell lines MFM-223 and ZR-75-1. Proliferation of MFM-223 and ZR-75-1 cells is inhibited by androgens. Ten nM 5alpha-dihydrotestosterone stimulated the expression of GCDFP-15 mRNA in MFM-223 (ca. 3-fold) and ZR-75-1 cancer cells (ca. 30-fold) as well as the secretion of GCDFP-15 into the culture medium. Competition experiments with DHT and the antiandrogens hydroxyflutamide and casodex confirmed the involvement of the AR in the regulation of GCDFP-15. Both antiandrogens inhibited GCDFP-15 mRNA expression even in the absence of DHT. AR mRNA was down-regulated in MFM-223 and ZR-75-1 cells (80 and 20% of the control, respectively) during incubation with DHT. Our data demonstrate the effective inhibition of GCDFP-15 expression by pure antiandrogens.

Androgen Antagonists↗
PubMed1992

Low hepatic clearance of peptide YY (PYY) in the perfused rat liver.

The hepatic clearance rate and secretion rate mainly determine peripheral plasma concentrations of regulatory peptides released from the gastrointestinal tract. In the present study hepatic extraction of peptide YY (PYY) during a single passage was investigated in the in situ perfused rat liver excluding modulating actions of circulating hormones. During perfusion of low amounts of PYY (50, 100, 500 pmol l-1), peptide concentrations in the portal vein (5.1 +/- 4.6, 98.1 +/- 2.6, 558 +/- 13.6 pmol l-1) and in the hepatic vein (50.2 +/- 1.4, 88.6 +/- 2.2, 503 +/- 18.1 pmol l-1 was only 22.1%. PYY had no influence on hepatic glucose and lactate production, portal flow as well as bile flow and bile acid secretion at these concentrations. PYY seems to traverse the liver almost intact and reaches the target organs without any significant hepatic extraction. Concomitant studies on metabolic and excretory functions of the liver showed no effect of PYY.

Animals↗
PubMedDate not supplied

Expression of placental protein 14 by the new endometrial cancer cell line MFE-280 in vitro and by endometrial carcinomas in vivo.

MFE-280 endometrial cancer cells express PP14 (placental protein 14) in vitro. PP14 is normally found in the secretory endometrium and in placental tissue. MFE-280 cells, which are tumorigenic in nude mice, were derived from a recurrent, poorly differentiated endometrial carcinoma. The cells were initially grown in suspension culture and later transferred to monolayer cultures. Karyotyping revealed near-diploidy with a complex heterogeneous aberration pattern. MFE-280 cells were positive for the cytokeratins 7, 8, 18 and 19 as well as for vimentin. The expression of PP14 in MFE-280 cells was demonstrated by immunochemistry and reverse transcriptase--polymerase chain reaction. PP14-mRNA was also detected in one out of five endometrial cancer specimen. In tumor tissue the expression of PP14 was not dependent on progestins.

Animals↗