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H Hess

Publications and source records attributed to H Hess.

At least 37 records · Page 2Linked to original sources
PubMed1995

The protein complexity of the cytoskeleton of bovine and human sperm heads: the identification and characterization of cylicin II.

The cytoskeletal calyx of mammalian sperm heads surrounding the basolateral part of the nucleus contains two kinds of basic proteins: Calicin, a polypeptide of approximate M(r) 60,000 as estimated from SDS-PAGE, and the group of the very basic cylicins (pI > 10.0), formerly designated as "multiple-band polypeptides." Recently, bovine cylicin I has been cDNA cloned and identified as a new type of a cytoskeletal protein, which contains numerous Lys-Lys-Asp tripeptides accumulated in nine central repetitive units predicted to form alpha-helices. We now report the cDNA cloning and localization of a second species of cylicin, bovine cylicin II, present in bovine and human sperm heads: Cylicin II (488 amino acids, M(r) 53,561, pI 10.55) shows the same prominent molecular characteristics as cylicin I, including a high content of charged amino acids, the abundance of Lys-Lys-Asp tripeptides, and repetitive units of presumably alpha-helical configuration, but also presents some differences. As with cylicin I mRNA, the 2.6-kb mRNA has also been shown to be specifically expressed in testis. The possible existence of a larger cylicin multigene family and its contribution to the cytoskeleton and the morphogenesis of the sperm head are discussed.

Amino Acid Sequence↗
PubMed1995

Molecular nature of calicin, a major basic protein of the mammalian sperm head cytoskeleton.

In the mammalian sperm head the nucleus is tightly associated, in many species in its posterior part, with a large and dense nonfilamentous cytoskeletal structure, the calyx, whose major proteins are basic, representing a novel category of cytoskeletal element. Using specific antibodies, biochemical methods, and cDNA cloning we have characterized one of these calyx proteins, previously termed calicin, in bull and man. The polypeptide of 588 amino acids (Mr of 66,889; IEP 8.1) is very similar in the two species and is encoded by a approximately 2.2-kb mRNA that has been detected only in testis but not in any other tissue or cell culture examined. Sequence analysis has revealed that calicin is homologous to the kelch protein of the ring canal structure of Drosophila ovaries. In particular, it contains three consecutive repeating units of 48 amino acids each which are homologous to the so-called "beta-strand folds" occurring in proteins of the kelch family, including the actin cross-linking protein scruin of Limulus sperm and a series of other eukaryotic, bacterial, and viral proteins. Moreover, the amino terminal domain of calicin contains a region of about 100 amino acids homologous to an extended motif shared by the kelch protein as well as various zinc finger and poxvirus proteins. The possible role of calicin as a morphogenic cytoskeletal element in spermiogenic differentiation is discussed, also in relation to the demonstrated absence or altered arrangement of calicin in frequent forms of human teratozoospermia such as "round-headed" or other "postacrosomal sheath defect" sperm malformations.

Amino Acid Sequence↗
PubMed1995

[Promoting breast feeding and the public health service].

This paper deals with the establishment of the National Breastfeeding Committee at the Robert-Koch-Institut and its activities. As the highest level scientific and advisory board for the German Federal Health Ministry the institute obtained permission from the state authorities to carry out a survey of the local health offices. A finding of this survey was that the different health offices apparently place different priorities on advising mothers in regard to breastfeeding. Some health offices offer medical counselling and others indicate that their counselling is carried out by non-medical personnel. In some cases the health offices reported a supply but no demand. We believe that the public health services should at least provide information on breastfeeding counselling in the community and on training opportunities for counsellors. The National Breastfeeding Commission will collect such information and provide it to the health offices and also give advice in the case of problems with regard to breastfeeding.

Breast Feeding↗
PubMed1994

Activating anti-idiotypic human anti-mouse antibodies for immunotherapy of ovarian carcinoma.

Human anti-mouse antibodies (HAMA) are observed frequently after immunoscintigraphy with monoclonal antibodies (MoAb) directed against CA-125. As the authors have shown previously, HAMA can cause false-positive CA-125 values in routine CA-125 immunoradiometric assay (IRMA) tumor-marker assays (in one case, up to 900 days after immunoscintigraphy). In 32 patients, the authors found a HAMA frequency of 34% (11/32: 3/7 after the first administration, 6/13 after the second, and 2/2 after the third). Ten patients developed extremely high CA-125 levels after undergoing the CIS IRMA assay (up to 80,000 U/ml) in parallel to a significant HAMA increase. The use of different assays, or HAMA removal before in vitro testing, can solve this problem. After a new CA-125 assay containing antibodies that recognize different epitopes on the CA-125 antigen (Biomira Tru-Quant OV) was applied, only mildly increased assay results or normal levels were measured. Most of HAMA-positive patients demonstrated a predominantly anti-idiotypic response, determined with two different HAMA assays. Seven patients with anti-idiotypic HAMA responses after OC-125 immunoscintigraphy remained free of tumor or had stable disease (2-42 or more months), contrary to their poor prognoses that had been made based on the underlying stages of their tumors. All of these patients are currently doing well (Karnofsky Index > 70%) and show no significant tumor progression. In light of their extremely poor prognoses (5-year survival rates of 3-5% in recurrent International Federation of Gynecology and Obstetrics III/IV stages), without further chemotherapy, these courses are extremely unusual. Preliminary in vitro experiments lead to the postulation that anti-idiotypic HAMA may trigger an antitumor effect either by suppressing the growth of CA-125-expressing cancer cells directly, or by activating the patient's immune response via induction of Ab3. Similar results are observed after immunoscintigraphy with a technetium-99m-labeled anti-CA-125 monoclonal antibody (B43.13), which the authors now also use for immunotherapy of ovarian cancer patients by repeated injections, hoping that induction of anti-idiotypic HAMA will be beneficial for prolonged survival of patients with ovarian carcinoma.

Animals↗
PubMed1994

Oct-4 transcription factor is differentially expressed in the mouse embryo during establishment of the first two extraembryonic cell lineages involved in implantation.

Oct-4 is the earliest expressed gene known to encode a transcription factor which is developmentally regulated during mammalian embryogenesis. In order to understand the role of Oct-4 in early murine embryogenesis, we carried out an analysis of the temporal and spatial pattern of protein expression. We report the presence of Oct-4 protein in cultured cells and murine embryos as determined by immunohistochemistry using confocal microscopy. Oct-4 protein is present in both embryonic stem cells and embryonal carcinoma cells, but is down-regulated following differentiation of these cells by culture in the absence of leukemia inhibitory factor or in the presence of retinoic acid, respectively. In embryos, the protein is found at low levels in unfertilized eggs and is localized predominantly to the pro-nuclei upon their formation following fertilization. The protein is present in the nuclei in all cleavage stages, but following differentiation of the trophectoderm at the blastocyst stage, Oct-4 protein is only expressed in the inner cell mass. The pattern of protein expression to this stage correlates well with previously reported in situ hybridization results; however, a striking difference was seen in primitive endoderm cells which had begun to differentiate and migrate along the inner surface of the trophectoderm. In direct contrast to RNA localization studies which demonstrate that there are only low levels of Oct-4 transcripts in primitive endoderm cells, protein expression in these early migrating cells is higher than in the inner cell mass.

3T3 Cells↗
PubMed1993

Affinity purification of histidine-tagged proteins.

Expression of recombinant proteins is a standard technique in molecular biology and a wide variety of prokaryotic as well as eukaryotic expression systems are currently in use. A limiting step is often the purification of the expressed recombinant protein, particularly if mammalian expression systems that yield low expression levels are employed. Here, we discuss the advantages and restrictions of tagging recombinant proteins with histidines and purifying them by Ni(2+)-NTA chromatography.

Animals↗
PubMed1993

Molecular characterization of mammalian cylicin, a basic protein of the sperm head cytoskeleton.

The cytoskeletal calyx structure surrounding part of the nucleus of the mammalian sperm head contains two major kinds of basic proteins, i.e., the approximately 60-kD calicin and a group of very basic (IEP > pH 10) polypeptides ranging in size from approximately 58 to approximately 100 kD ("multiple band proteins," MBPs). We have produced MBP-specific mAbs and have isolated a bovine and a human cDNA clone encoding one of these proteins, termed "cylicin" (from the Greek word c eta kv lambda l zeta for cup or beaker). Bovine cylicin I of a calculated molecular weight of 74,788 contains a high proportion (29%) of positively charged amino acids, resulting in an IEP of 10.55, numerous KKD tripeptides, and is characterized by an organization of the central part of the molecule in nine repeating units of maximally 41 amino acids each of which according to prediction analysis should tend to form an alpha helix. The identity of the polypeptide has been proven by direct amino acid sequencing of > 14 different fragments and by experiments using antibodies raised against a partial cDNA-derived protein segment produced in E. coli. By Northern blot analysis we have identified the 2.4-kb cylicin I mRNA only in testis. The unusual cytoskeletal protein cylicin is compared with other proteins and its possible architectural role during spermiogenesis is discussed.

Amino Acid Sequence↗
PubMed1992

High-level secretion of the four salivary plasminogen activators from the vampire bat Desmodus rotundus by stably transfected baby hamster kidney cells.

The cDNAs coding for the four Desmodus rotundus salivary plasminogen activators (DSPAs) were subcloned into the mammalian expression vector, pMPSV/CMV, which carries the myeloproliferative sarcoma virus promoter and the cytomegalovirus enhancer. These constructs were transfected, together with plasmids harbouring Geneticin (G418)-resistance and puromycin-resistance genes, into baby hamster kidney cells. Through the selective pressure of both antibiotics, cell clones constitutively overexpressing the DSPA alpha 1, DSPA alpha 2, DSPA beta or DSPA gamma cDNAs were obtained. Secretion of active DSPAs was confirmed by zymographic analysis and quantified using a fibrin plate assay and ELISA.

Animals↗
PubMed1992

Purification and properties of a secreted and developmentally regulated alpha-L-fucosidase from Dictyostelium discoideum.

During its development the eukaryotic microorganisms Dictyostelium discoideum secretes an alpha-L-fucosidase (EC 3.2.1.51). In cells of the growth phase almost no alpha-L-fucosidase activity is detectable. The activity increases steadily up to the aggregation stage and accumulates also in the extracellular medium. The developmental regulation is mediated by pulsatile cAMP signals. The alpha-L-fucosidase was purified from extracellular medium. The isolation procedure started with concentration of the enzyme by batchwise anion-exchange chromatography and ammonium sulfate precipitation, followed by Sephacryl S-300 gel filtration and further purification by fast protein liquid chromatography on Mono Q, phenyl-Superose, and finally Superose 12. The purified preparation was found to be essentially free of activities of six other glycosidases also secreted by D. discoideum. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the purified enzyme showed one major band with an apparent molecular mass of 62 kilodalton. Gel filtration of the enzyme on a Superose 12 column was consistent with an active monomer. A monoclonal antibody was produced, which recognizes a carbohydrate epitope shared by all lysosomal enzymes in D. discoideum. The pH optimum of the alpha-L-fucosidase is at 3.7. The apparent Michaelis constant for p-nitrophenyl alpha-L-fucoside as substrate is 1.2 mM. The enzyme catalyzes preferentially the hydrolysis of alpha 1----6GlcNAc but also of alpha 1----2Gal and alpha 1----3Glc fucosyl linkages.

Animals↗
PubMed1992

Purification of serum amyloid A and its isoforms from human plasma by hydrophobic interaction chromatography and preparative isoelectric focusing.

The present work was aimed at isolating human serum amyloid A, (SAA), an acute-phase protein mainly complexed to high density lipoproteins, directly from human plasma without sequential ultracentrifugation of lipoproteins and subsequent delipidation of the apolipoprotein moiety. Hydrophobic-interaction fast-protein liquid chromatography on Octylsepharose, using stepwise gradient elution profiles under dissociating conditions, followed by fast-protein liquid-gel permeation chromatography on a Superdex TM75 column revealed a higher than 95% purity of isolated SAA. Further purification of SAA from coeluting apolipoproteins C and A-II was achieved by preparative isoelectric focusing between pH5-7 using a Rotofor apparatus. Separation of the main SAA isoforms, SAA1 (pI 6.5) and SAA1 des-Arg (pI 6.0, lacking the N-terminal arginine), was achieved by anion-exchange fast-protein liquid chromatography on a Fractogel EMD DEAE 650-S column. The purity of the SAA1 and SAA1 des-Arg isoforms, thus isolated, was checked by immunochemical techniques and amino acid analysis. With the described method various SAA isoforms can be isolated, purified and separated directly from human plasma/serum without prior ultracentrifugation.

Blotting, Western↗
PubMed1992

[A rare variation in the zone of the carotid artery].

An extremely rare variation in the angioarchitecture of the carotid arteries consists in the complete missing of the right common carotid artery. The brachiocephalic trunc (innominate artery), forming a bulbus-like extension, branches out into three major stems: internal carotid artery, external carotid artery and the right subclavian artery. The variation is embryologically explainable: The aortic arches III and IV arise together (without ventral aortic root between them) from the persisting initial segment of the right ventral aorta.

Aorta, Thoracic↗
PubMed1991

[The Malleotrain bandage in a large clinical trial].

The authors tested the clinical efficacy of the malleotrain bandage in a clinical field trial on a very large mixed patient material from 1980 onwards. The patient material included a total of 350 cases of ankle joint injuries with partial and total fibular ruptures of ligament, ruptures of the inferior tibiofibular joint, conditions after malleolar fractures as well as posttraumatic or postoperative swelling.--It was found that the malleotrain bandage achieved subsidence of swelling of the periarticular soft parts, relief of complaints and considerable normalisation of functioning, within an unusually short time and without medication or other local measures.--Patients who had been operated on for complete rupture of fibulotalar ligament were given by Lippay the malleotrain bandage only, after having immobilised the malleolus by means of a plaster cast for 10 days, without any disadvantages in respect of healing and subsequent stability.--Blandfort had even treated complete lateral ankle joint ligament ruptures conservatively with the malleotrain bandage only and had thus achieved cure resulting in stable ligaments.--The ability to work and to resume sports activities returned on the average two weeks earlier than with plaster cast immobilisation.

Adolescent↗
PubMed1991

[Kimura disease--2 case reports].

Two histologically confirmed cases of Kimura's disease are reported in the present article. Emphasis is placed on the clinical symptoms in conjunction with the histological picture. Recent studies in the literature are discussed with respect to differential diagnosis, etiology and therapy. In all ENT-tumours of unknown origin this relatively uncommon disease should also be considered.

Angiolymphoid Hyperplasia with Eosinophilia↗
PubMed1991

[Local low dosage thrombolysis with rt-PA. Systemic effects on the fibrinolytic system--data on the assessment of the value and risk of this method].

We investigated 70 patients suffering from peripheral vascular disease for alterations in fibrinolytic parameters before, during and twice after local, low dose thrombolysis with rt-PA (1 - 7.5 mg). Recanalization was achieved in all 10 embolic occlusions and in 87% of 60 thrombotic occlusions. We found no alterations of fibrinogen and plasminogen plasma levels, but significant consumption of antiplasmin 5 min after the end of rt-PA application. Degradation products of fibrinogen and fibrin showed a parallel increase only during the therapy. PAI I concentrations significantly increased until the 2nd day after the therapy. Since we limited the maximum dose of rt-PA to 7.5 mg we never saw systemic bleeding or embolisation in more than 300 cases.

Aged↗
PubMed1990

[Experiences with joint-preserving operations in arthrosis of the upper ankle joint].

During a period of ten years we performed 140 joint conserving operations on patients with arthrosis of the ankle joint. The use of this procedure was analysed in 85 patients, whom we followed up. Mainly (in 89%) positive results were obtained. The success of such joint conserving surgery depends on the one hand on the seriousness of the injury leading to arthrosis and on the other hand on the duration of the complaints. If attention is paid to these factors we have after the failure of conservative therapy a satisfying complementary treatment before using the arthrodesis.

Adolescent↗
PubMed1990

[Digital subtraction angiography using carbon dioxide: an alternative to arteriography of the extremities using iodine-containing contrast media].

The basics and the technique of intraarterial digital subtraction arteriography with carbon dioxide (CO2) are presented. The procedure turned out to be a good and relatively poor-risk alternative to conventional angiography with iodinated contrast media in 26 peripheral arteriographies and in 6 peripheral angioplasties in hyperthyroid patients. Using a 9-inch amplifier, arteriograms from the infrarenal abdominal aorta down to the lower leg arteries were performed with five series of insufflation of 20-25 cc CO2 each. With regard to the image quality, there is no difference between CO2 arteriograms and those performed with intraarterial application of iodinated contrast media.

Aged↗