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- Bjartell, Anders, et al.
(author)
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Distribution and tissue expression of semenogelin I and II in man as demonstrated by in situ hybridization and immunocytochemistry
- 1996
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In: Journal of Andrology. - 0196-3635. ; 17, s. 17-26
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Journal article (peer-reviewed)abstract
- Semenogelin I and II (Sgl, Sgll) are two separate gene products of chromosome 20 with extensive (80%) identity in primary structure. They are mainly responsible for immediate gel formation of freshly ejaculated semen. Degradation of Sgl and Sgll is due to the proteolytic action of prostate-specific antigen (PSA); it results within 5-15 minutes in liquefaction of semen and release of progressively motile spermatozoa. By means of cDNA cloning and Northern blots, Sgl and Sgll transcripts have previously been shown to be abundant in human seminal vesicles, but Sgll alone is suggested to be expressed at low levels in the epididymis. To characterize the expression and tissue distribution of Sgl and Sgll in greater detail, we produced monoclonal immunoglobulin Gs (lgGs for immunocytochemistry (lCC) and specific [35S]-, digoxigenin-, or alkaline phosphatase-labeled 30-mer antisense probes to Sgl and Sgll for in situ hybridization (lSH). Immunocytochemical staining for both Sgl and Sgll, and lSH detection of both Sgl and Sgll transcripts, were demonstrated in the cytoplasm of seminal vesicle epithelium. lSH showed Sgll alone to be expressed in the epithelium of the epididymal cauda. Neither lCC nor lSH yielded any evidence of Sgl or Sgll expression in caput or corpus epithelium or in any stromal cells of the epididymis. Consistent with our previous findings using polyclonal lgG, monoclonal anti-Sgll Sgll lgGs identified epitopes on the posterior head, midpiece, and tail of ejaculated spermatozoa. Spermatozoa in the epididymal cauda were also immunoreactive, but those in the caput or corpus region of the epididymis as well as those in the testis were negative. As shown by lCC, neither Sgl nor Sgll were expressed in the testis, the prostate, the female genital tract, or other normal human tissue specimens. Although the significance of Sg attachment to epididymal and ejaculated spermatozoa remains to be established, monoclonal anti-Sg lgG might prove useful in establishing the origin of seminal vesicle tissue components in prostate core biopsies or other biopsy specimens.
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2. |
- Denmeade, Samuel R., et al.
(author)
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Specific and efficient peptide substrates for assaying the proteolytic activity of prostate-specific antigen
- 1997
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In: Cancer Research. - 0008-5472. ; 57:21, s. 4924-4930
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Journal article (peer-reviewed)abstract
- Prostate-specific antigen (PSA) is a serine protease secreted by hath normal prostate glandular celts and prostate cancer cells. The major proteolytic substrates for PSA are the gel-forming proteins in semen, semenogelin (Sg) I and II. On the basis of the PSA cleavage map for Sg I and II, a series of small peptides (ie., ≤ 7 amino acids) was synthesized and coupled at the COOH terminus to 7-amino-4-methyl coumarin. Using these fluorescently tagged substrates, K(m)s and k(cm)s were determined for PSA hydrolysis, and the substrates were also tested for activity against a panel of purified proteases. Previously, a variety of chymotrypsin substrates have been used to assay the enzymatic activity of PSA. The present studies have identified a peptide sequence with a high degree of specificity for PSA (i.e., no detectable hydrolysis by chymotrypsin) and improved K(m)s and k(cat)s over previously used substrates. On the basis of these parameters, the best peptide substrate for PSA has the amino acid sequence HSSKLQ. Using PC-82 human prostate cancer xenografts and human prostate tissues, this PSA substrate was used to document that prostate cancer cells secrete enzymatically active PSA into the extracellular fluid but that once in the blood, PSA is not enzymatically active. On the basis of this information, it should be possible to use the HSSKLQ peptide as a carrier to target peptide- coupled prodrugs for selective activation within sites of PSA-secreting, metastatic prostate cancer cells and not within the blood or other nonprostatic normal tissues.
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3. |
- Egesten, Arne, et al.
(author)
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Eosinophil leukocyte degranulation in response to serum-opsonized beads: C5a and platelet-activating factor enhance ECP release, with roles for protein kinases A and C
- 1998
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In: Allergy. - : Wiley. - 1398-9995 .- 0105-4538. ; 53:11, s. 1066-1073
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Journal article (peer-reviewed)abstract
- BACKGROUND: Eosinophils have a typical content of granule-bound, cytotoxic, cationic proteins which may, when released to the external milieu, play roles in diseases such as asthma and parasitic infestation. Therefore, we have investigated possible mechanisms by which their release is regulated in eosinophils. METHODS: The enzyme-linked immunosorbent assay (ELISA) was used to detect released eosinophil cationic protein (ECP). Release of ECP was induced by serum-opsonized, nonphagocytosable Sephadex beads (SOS). RESULTS: The complement fragment C5a and platelet-activating factor (PAF) were found to enhance ECP release in response to SOS in a dose-dependent fashion, and, contrary to previous reports, they were not found to act as secretagogues themselves on eosinophils in suspension. The role of protein kinase C (PKC) in eosinophil degranulation has been controversial. We found that ECP release induced by SOS was inhibited by the PKC inhibitors staurosporine and calphostin C. Activation of protein kinase A (PKA), by raising cAMP, also inhibited ECP release. Furthermore, pertussis toxin decreased ECP release on opsonized beads, indicating the involvement of pertussis-toxin-sensitive G proteins. CONCLUSIONS: C5a, and PAF enhance granule release, rather than acting as secretagogues themselves. PKC and PKA have opposing roles in the regulation of ECP release in response to SOS.
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5. |
- Hallgren Larsson, Eva, et al.
(author)
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Luftföroreningar i södra Sverige 1985-1995
- 1997
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Reports (other academic/artistic)abstract
- Regional (länsvis) övervakning av försurade luftföroreningar, svavel och kväve, i tio län i södra Sverige har utvärderats av IVL. Utvärderingen omfattar tio års mätningar, oktober 1985 till september 1995. Undersökningarna har initierats av luftvårdsförbund, länsstyrelser och andra länsindelade organisationer. Länen har ett gemensamt basprogram som omfattar nedfallsmätningar på öppet fält och i skog (krondroppsmätningar) samt markvatten på ett 70-tal lokaler. På vissa lokaler ingår lufthaltsmätningar. Syftet med mätningarna är att beskriva tillstånd, regionala skillnader, samt utveckling i tiden. Undersökningarna genomförs huvudsakligen i skogsvårdsorganisationens observationsytor, vilket ger tillgång till övrig information, som exempelvis kronutglesning, tillväxt samt markkemiska data. För svavel och havssalter visar undersökningarna total belastning och regional variation. På grund av upptag i trädkronorna kan krondroppsvärden ej användas som mått på totalt nedfall av kväve. Däremot framgår regional variation och områden med förhöjd kvävebelastning kan identifieras. Nedfall av svavel och kväve har varit betydligt större än Nturvårdsverkets miljömål för Götaland. Resultaten visar en markant gradient med större deposition i söder än i norr. Markvattenresultaten avspeglar i stora drag depositionsgradienten med kraftig försurningspåverkan på många platser i södra Sverige. Trendberäkningar på markvattnets sammansättning visar en fortlöpande försurningsprocess under mätperioden, trots att nedfallet av svavel har minskat. Lufthalter av svaveldioxid var högre i söder än längre norrut, och har avtagit under perioden. Kvävedioxid i luft uppvisar högre halter i trafikintensiva områden. Högst halter av ammoniak förekommer i områden med intensiv djurhållning. Naturvårdsverkets miljömål för marknära ozon överskreds vid samtliga mätlokaler. Belastningen av svavel och kväve i södra Sverige domineras av utländska bidrag. Internationella överenskommelser om utsläppsbegränsade åtgärder är därför av största vikt. I brukad skog i Sverige är åtgärder med anpassat uttag av trädbiomassa och kompensationsgödsling, samt klakning och vtaliseringsgödsling, väl så viktiga. Provytornas bonitet, stamtäthet, trädhöjd, grundyta, förekomst av skogsskador och marktillstånd beskrivs. Vid urval av skogsytor för depositionsmätningar har likartade granytor eftersträvats. Undersökningarna visar inget samband mellan markvattnets försurningstillstånd och skogens tillväxt eller förekomst av kådrinning. Multivariat statistisk analys indikerar att barrutglesning samvarierar med många faktorer i ett komplext skogsekosystem. Utförda modellberäkningar av massbalanser i skogsytor visar i många fall nettförluster av baskatjoner (försurningen ökar) samt upplagring av kväve.
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6. |
- Malm, Johan, et al.
(author)
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Isolation and characterization of the major gel proteins in human semen, semenogelin I and semenogelin II
- 1996
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In: European Journal of Biochemistry. - : Wiley. - 0014-2956 .- 1432-1033. ; 238:1, s. 48-53
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Journal article (peer-reviewed)abstract
- Semenogelin I and semenogelin II constitute the major gel-forming proteins in human semen. The gel proteins were rapidly solubilized and separated from spermatozoa in ejaculates collected at pH 9.7 in buffer containing 4 mol/l urea and dithiothreitol. This protected the semenogelins from proteolytic degradation by prostate-specific antigen, and allowed their isolation by affinity chromatograph:g on heparin-sepharose. Semenogelins I and II were almost selectively retained and eluted partially separated in 0.25 mol/l NaCl. Further purification was achieved by chromatography on Superose. Approximately 10-20 mg semenogelin I and 2-5 mg semenogelin II were recovered from each sample with a purity exceeding 95% as judged by SDS/PAGE. The molecular mass of semenogelin I (49,958 Da) and the major form of semenogelin II (63,539 Da) measured by mass spectrometry was consistent with the reported cDNA data. The occurrence of a second, larger form of semenogelin II was due to asparagine-linked glycosylation. The amino-termini of the purified proteins were blocked, but digestion with pyroglutamate aminopeptidase enabled the identification of amino-terminal sequences consistent with the reported cDNA data. The amino acid compositions of the purified proteins were also consistent with those derived from cDNA data. The absorption coefficients (280 nm, 1%, 1 cm) for semenoaelins I and II. were 5.5 and 5.4, respectively, and the isoelectric point was above pH 9.5 for both proteins.
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7. |
- Peter, A., et al.
(author)
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Semenogelin I and semenogelin II, the major gel-forming proteins in human semen, are substrates for transglutaminase
- 1998
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In: Eur J Biochem. ; 252:2, s. 21-216
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Journal article (peer-reviewed)abstract
- The major seminal vesicle secreted proteins in human semen, semenogelin I and semenogelin II, interact non-covalently and via disulphide bridges to instantly form a coagulum upon ejaculation. The coagulum is liquefied after a few minutes due to the action of a prostatic serine protease, prostate-specific antigen (PSA). In contrast to rat semen, which forms an insoluble plug within minutes of expulsion, no transglutaminase-mediated cross-linking has been demonstrated in ejaculated human semen. However, we here show that semenogelin I and semenogelin II, both in seminal vesicle fluid and purified from semen, are substrates for factor XIIIa, the fibrin cross-linking transglutaminase. The cross-linking of the semenogelins, which was conformation-dependent, and the incorporation of a fluorescence-labelled amine, were visualised by SDS/PAGE and Western blot. Purified semenogelin I and semenogelin II could be cross-linked separately into complexes. Moreover, digestion of semenogelin with PSA produced fragments, some of which were cross-linked into complexes by factor XIIIa. We also found that PSA was unable to release any semenogelin fragments during exposure of the high molecular-mass complexes of cross-linked semenogelin to active PSA.
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