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S Sander

Publications and source records attributed to S Sander.

At least 55 records · Page 3Linked to original sources

Osteoprotegerin: a novel secreted protein involved in the regulation of bone density.

A novel secreted glycoprotein that regulates bone resorption has been identified. The protein, termed Osteoprotegerin (OPG), is a novel member of the TNF receptor superfamily. In vivo, hepatic expression of OPG in transgenic mice results in a profound yet nonlethal osteopetrosis, coincident with a decrease in later stages of osteoclast differentiation. These same effects are observed upon administration of recombinant OPG into normal mice. In vitro, osteoclast differentiation from precursor cells is blocked in a dose-dependent manner by recombinant OPG. Furthermore, OPG blocks ovariectomy-associated bone loss in rats. These data show that OPG can act as a soluble factor in the regulation of bone mass and imply a utility for OPG in the treatment of osteoporosis associated with increased osteoclast activity.

Amino Acid Sequence↗

The predominant protein in peroxisomal cores of sunflower cotyledons is a catalase that differs in primary structure from the catalase in the peroxisomal matrix.

This paper describes a biochemical study on the protein composition of crystalline inclusions (cores) from plant peroxisomes. By SDS/PAGE and immunoblotting, a catalase of 59 kDa was identified as the predominant protein component in purified cores from sunflower (Helianthus annuus L.) cotyledons. A 55-kDa catalase was the only additional peptide detected. In contrast to in cores, the 55-kDa catalase was the major catalase protein in matrix fractions obtained from lysed peroxisomes. These findings suggested two peroxisomal populations of catalase differing in molecular structure and subperoxisomal compartmentation in sunflower cotyledons. Evidence for different amino acid sequences of the two catalases was found by peptide mapping with endoproteinase Glu-C, by expressing a cDNA encoding matrix catalase in Escherichia coli, and by partial amino acid sequencing of peptide fragments from 59-kDa core catalase. These results contradict the previous view that the formation of cores occurred via condensation of matrix catalase, and indicate that new concepts on the biogenesis and physiological function of plant peroxisomal cores need to be developed.

Amino Acid Sequence↗

Dilated cardiomyopathy-associated proteins and their presentation in a WWW-accessible two-dimensional gel protein database.

High resolution two-dimensional electrophoresis (2-DE) and computer-assisted image analysis were used to screen 13 patients suffering from dilated cardiomyopathy (DCM) versus 15 control patients for quantitative and qualitative differences in their myocardial protein expression. Right atrial tissue samples were obtained from end-stage failing explanted hearts and control hearts. Fifty-two spots differed significantly in average intensity between the DCM and the control groups. Myosin light chain 2, ventricular (MLC2) and heat shock protein HSP 27 were identified by protein microsequencing and gel map comparison with other databases. These proteins were found to be characteristic protein markers for DCM in the right atrium. In DCM patients, the spot intensity (protein abundance) of MLC2 is increased to 336% and HSP 27 is decreased to 59%, compared to the control group. The HEART-2DPAGE, a World Wide Web-accessible 2-DE database, was used and extended for the presentation of these disease-associated proteins. Retrievable via Internet we present a list of disease-associated proteins, their altered level of expression in DCM, and their position on a right atrial protein pattern. The accession number to protein sequence databases confers a connection to databases like SWISS-PROT to obtain a detailed functional and structural description of disease-associated proteins. New DCM-associated proteins are detected and their presentation in a 2-DE gel protein database is described.

Cardiomyopathy, Dilated↗

Comparison of urodynamic investigations before and after posterior sagittal anorectoplasty for anorectal malformations.

METHODS: The authors evaluated 21 patients (10 boys, 11 girls) who had anorectal malformations (ARM). Ten of them had infralevator (low-group I) and 11 of them had supralevator (high-group II) type ARM. All of the patients underwent urodynamic investigation before and after posterior sagittal anorectoplasty (PSARP) operation. RESULTS: Sacral and spinal anomalies were found in 54% (6 of 11) patients who had supralevator type ARM. None of the patients with infralevator type ARM had additional sacral or spinal anomalies. Before PSARP operation urodynamic investigations of all infralevator type ARM patients were within normal limits, whereas 82% (9 of 11) of patients with supralevator type ARM showed neurovesical dysfunction (NVD). There was no significant difference between the preoperative and postoperative urodynamic findings. The possibility of additional sacral or spinal anomalies and NVD in supralevator type ARM was high. After PSARP operation no additional lower urinary tract dysfunction was detected in the urodynamic evaluation of ARM patients.

Anal Canal↗

The construction of the World Wide Web-accessible myocardial two-dimensional gel electrophoresis protein database "HEART-2DPAGE": a practical approach.

The construction of the two-dimensional electrophoresis (2-DE) gel protein database "HEART-2DPAGE" for human heart proteins, accessible via the World Wide Web (WWW), is described. This database provides the opportunity to retrieve descriptive information interactively by mouse clicking on a protein spot within a 2-DE gel image or to retrieve the position of a protein if its protein name or a search expression is given. The realization of searching for proteins, the creation of clickable spots, marked by crosses or textual information, and interactive viewing opportunities are discussed from a software-oriented point of view. The database takes into account that some human heart proteins are chamber specific. Several Common Gateway Interface (CGI) scripts are described and some practical experience is discussed.

Computer Communication Networks↗

Adsorptive stripping voltammetric determination of vanadium as chloranilic acid complex.

Traces of vanadium(V) can be determined up to 21 ng/l by adsorptive stripping voltammetry using 2,5-dichloro-1,4-dihydroxy-3,6-benzoquinone (chloranilic acid) as complex forming reagent. The complex is stable in a 0.1 mol/l acetate buffer (pH 4.6) solution and adsorbed at the electrode surface in a potential range between -150 mV and -400 mV. The adsorption process is solved by alternating current (ac) voltammetric measurements. The method is applied to different real samples.

Journal Article↗

Role of the native kidney in experimental post-transplantation hypertension.

In experimental renal transplantation studies using several animal models of primary hypertension, including stroke-prone spontaneously hypertensive rats (SHRSP) and their normotensive Wistar-Kyoto controls (WKY), single transplanted kidneys from genetically hypertensive but not normotensive donors elicited post-transplantation hypertension in bilaterally nephrectomized genetically normotensive recipients. The underlying mechanisms are presently unclear. The present study was designed to investigate the effects of a remaining native kidney on post-transplantation blood pressure, plasma renin activity and plasma angiotensin II concentration in (WKYxSHRSP) F1 hybrid recipients of a WKY or SHRSP kidney. The presence of a native kidney markedly reduced, but did not prevent, post-transplantation hypertension in recipients of an SHRSP kidney. WKY kidney grafts did not significantly alter blood pressure in bilaterally or unilaterally nephrectomized recipients. Plasma renin activity was lower in bilaterally than in unilaterally nephrectomized recipients, regardless of the source of the graft. The plasma angiotensin II concentration was similar in all groups. Renal graft function as assessed by 99mtechnetium-mercaptoacetyltriglycine scintigraphy was well preserved. These data suggest that post-transplantation hypertension in recipients of an SHRSP kidney may be partly due to the failure of the graft to eliminate a hypertensinogenic substance or to produce a blood pressure lowering agent.

Angiotensin II↗

Analysis of 21 Stargardt's disease families confirms a major locus on chromosome 1p with evidence for non-allelic heterogeneity in a minority of cases.

BACKGROUND: Autosomal recessive Stargardt's disease is a macular degeneration characterised by a juvenile onset and a rapidly progressive course resulting in an atrophic macular area typically surrounded by yellowish retinal flecks. METHOD: The disease locus has previously been assigned to markers from chromosome 1p21-p13 by genetic linkage analysis in eight multiplex Stargardt's disease families. RESULTS: In an extended analysis, the assignment to chromosome 1p was confirmed in the majority of the 21 families with Stargardt's disease who were studied. In addition, a series of recombinant chromosomes further narrowed the Stargardt's disease region to an approximately 3 cM interval between markers at D1S424 and D1S497. CONCLUSION: Multipoint linkage analysis most probably excludes this locus in three of these families suggesting non-allelic heterogeneity with at least one additional minor Stargardt's disease locus.

Chromosomes, Human, Pair 1↗

X-linked juvenile retinoschisis (RS) maps between DXS987 and DXS443.

X-linked juvenile retinoschisis (RS) has previously been localized to a 7-8 cM interval between markers at (DXS43, DXS207) and (DXS274, DXS41). Our analysis of more than 300 meioses in two multigeneration RS families identified eight recombinant RS chromosomes and narrowed the RS locus to an interval between DXS987 and DXS443. Our data suggest the following order of loci: Xpter-DXS207-DXS987-([DXS418-DXS999], RS)-DXS443-DXS365-DXS274-Xcen.

Base Sequence↗

Stimulation of DNA synthesis by endothelin-1 in primary cultures of human dental pulp.

Endothelin (ET), besides being a powerful vasoactive agent, acts as a mitogen in some cell types. ET-like immunoreactivity has been recently detected by immunocytochemistry in the vascular endothelium of human tooth germ and dental pulp, thus providing evidence for local ET production in these tissues. The effects of ET-1 on DNA synthesis in primary cultures of human dental pulp were now investigated. DNA synthesis was evaluated by flow cytometric assay and by 5-bromo,2'deoxyuridine incorporation as detected by immunocytochemistry. Cultured cells were morphologically similar to dental pulp cells and displayed vimentin immunoreactivity. Incubation of cultures with ET-1 resulted in a dose-dependent increase in the number of S-phase-traversing cells over control (unstimulated) cultures. Control skin fibroblasts were also responsive to ET. This finding raises the possibility that the multifunctional peptide ET-1 might subserve growth-promoting activity in the human tooth. It is tentatively suggested that such as an activity might be important during tooth development and in pulp inflammation and healing.

Adolescent↗

High-resolution meiotic and physical mapping of the best vitelliform macular dystrophy (VMD2) locus to pericentromeric chromosome 11.

Best vitelliform macular dystrophy (VMD2) has previously been linked to several microsatellite markers from chromosome 11. Subsequently, additional genetic studies have refined the Best disease region to a 3.7-cM interval flanked by markers at D11S903 and PYGM. To further narrow the interval containing the Best disease gene and to obtain an estimate of the physical size of the minimal candidate region, we used a combination of high-resolution PCR hybrid mapping and analysis of recombinant Best disease chromosomes. We identified six markers from within the D11S903-PYGM interval that show no recombination with the defective gene in three multigeneration Best disease pedigrees. Our hybrid panel localizes these markers on either side of the centromere on chromosome 11. The closest markers flanking the disease gene are at D11S986 in band p12-11.22 on the short arm and at D11S480 in band q13.2-13.3 on the proximal long arm. This study demonstrates that the physical size of the Best disease region is exceedingly larger than previously estimated from the genetic data, because of the proximity of the defective gene to the centromere of chromosome 11.

Base Sequence↗

Survival after transurethral and transvesical surgery in localized cancer of the prostate, Norway 1957-1981.

BACKGROUND: During the period 1957-1981, there has been a gradual change in the choice of surgical methods for patients with prostate cancer in Norway, from transvesical surgery to transurethral resections (TUR-P). Radical prostatectomy was practically nonexistent in the early years of this time period. Sixty-five percent (17,696 patients) of all patients with prostate cancer reported to the Cancer Registry had no metastases at the time of diagnosis. Of these, 5414 patients underwent TUR-P, whereas 6160 patients underwent transvesical operations as primary surgery. Interest was raised in analyzing survival after primary surgery. METHODS AND RESULTS: Five-year relative survival rates were calculated for the groups of patients undergoing each type of surgery; the rates increased steadily for both groups during the later years of the 1957-1981 period. However, survival consistently was better for patients who had transvesical surgery. The difference in 5-year relative survival rates was 10-15%. The same pattern was seen long-term survival (more than 10 years). In addition, survival rates for patients with similar grade of tumor differentiation were better for patients undergoing transvesical surgery. A multivariate analysis of survival that related age, surgical methods, grades of tumor differentiation, and diagnostic periods showed that survival was influenced most by differentiation, followed by surgery. Age was not an important factor in this analysis. CONCLUSION: The results underline the importance of additional research regarding the precise classification of prostatic cancer at the time of diagnosis so that clinicians can better choose the proper method of surgery.

Age Factors↗

[Single transurethral microwave therapy of benign prostatic hyperplasia].

We have used transurethral microwave thermotherapy in the treatment of benign prostatic hyperplasia since October 1991. Irreversible cell damage occurs when the microwaves heat the periurethral prostatic tissue. The urethra is simultaneously cooled, and is not destroyed during treatment. The patients are not hospitalized. Transurethral microwave thermotherapy is performed under local anaesthesia, no other form of analgesia has been found necessary. We have included patients with symptomatic prostatic obstruction who would otherwise have received operative or pharmacologic treatment. Patients with high residual urine, large middle lobe, urethral stricture, prostatic cancer, decreased renal function, urinary infection or metal implants were excluded. We observed a marked improvement in the Madsen symptom score after transurethral microwave thermotherapy. The score decreased from 12 before treatment to five after six weeks and 4.6 after six months (p < 0.0001). Flow increased from 8.9 to 9.7 ml/s. There was a significant reduction in the residual urine from 102 ml preoperatively to 69 ml after six months (p < 0.001). The volume of the prostate was only slightly reduced after transurethral microwave thermotherapy. Postoperative edema caused urinary retention in 13% of the patients. Two patients required transurethral resection of the prostata.

Aged↗

[Endocrine treatment of prostatic cancer. A renaissance for parenteral estrogen].

The standard treatment for advanced cases of cancer of the prostate is castration. Oestrogens, administered per os may have serious side effects, in particular thrombosis and cardiovascular complications. If the oestrogens are administered parenterally, changes in liver function can be avoided and risk of side effects markedly reduced. 38 patients have been treated at Huddinge Hospital in Stockholm, and 14 patients at Aker Hospital in Oslo, with polyoestradiol phosphate (Estradurin) 240 mg injected intramuscularly every 4th week (initial dose 320 mg). We can sum up our own experience as follows: Plasma testosterone is reduced to castration level after 2-3 weeks. Liver function, evaluated by the sexual hormone binding globulin level in plasma, remains unchanged. Morbidity and mortality from cancer are the same as may be achieved by surgical orchidectomy. The only side effect of significance is gynaecomastia. Follow-up of the patients does not indicate any increased risk of thrombosis or cardiovascular disease. The treatment is fairly cheap compared with other alternative methods of endocrine treatment.

Estradiol↗

Neoadjuvant chemotherapy in bladder cancer: a randomized study. Nordic Cystectomy Trial I.

An analysis by the Nordic Cooperative Bladder Cancer Study Group concerned the possible benefit of neoadjuvant chemotherapy--given before scheduled low-dose irradiation and cystectomy. In the trial, started in 1985, 311 patients with locally advanced bladder cancer, T1 grade 3, T2-T4a NXMO, were randomly allocated to a 'chemotherapy' or a 'no chemotherapy' group. Chemotherapy consisted of two cycles comprising cisplatin 70 mg/m2 and doxorubicin 30 mg/m2, with a 3-week interval between cycles 1 and 2. All patients were locally irradiated with 4 Gy daily for 5 consecutive days. The follow-up included 266 cystectomized patients. In May 1992 the mean observation time was 18 months for all patients and 47 months for those still alive. The results suggest that a significant downstaging in the group randomized to chemotherapy was found only in T1, grade 3 tumours (56 patients, p = 0.002). The overall survival rate in all 311 patients was significantly higher in the chemotherapy group (p = 0.03) and likewise among the 253 patients with T2-T4a tumour (p = 0.018). For the 210 patients who underwent cystectomy for T2-T4a tumour, there was a trend towards longer survival when chemotherapy was given (p = 0.057). Patients with initially muscle-invasive tumour who responded to neoadjuvant treatment survived longer than non responders (p = 0.0005). The results suggest that neoadjuvant chemotherapy improve the outcome of radical surgery for muscle-invasive bladder cancer, though the effect on long-term survival is inconclusive. Further studies on the effect of neoadjuvant chemotherapy is initiated.

Antineoplastic Combined Chemotherapy Protocols↗

Localized prostate carcinoma treated with TUR and neodymium-YAG laser irradiation.

Neodymium-YAG laser irradiation subsequent to extended transurethral resection has been practised in our department since 1981 as an alternative treatment for patients with localized prostate carcinoma. The treatment is performed endoscopically in two separate steps. The procedure is simple and complications are few. One hundred and twenty-four patients have been treated and followed up for more than 6 months. One hundred and ten patients are evaluated as disease free survivors and the overall actuarial disease free survival rate is 88% at 4-9 years of follow-up. The initial promising results persist and the results from other clinics confirm the method to be a fair alternative or patients with localized prostate carcinoma.

Humans↗