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Hou S, Larsen RW, Boudko D, Riley CW, Karatan E, Zimmer M, Ordal GW, Alam M. Myoglobin-like aerotaxis transducers in Archaea and Bacteria. Nature 2000; 403:540-4. [PMID: 10676961 DOI: 10.1038/35000570] [Citation(s) in RCA: 199] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Haem-containing proteins such as haemoglobin and myoglobin play an essential role in oxygen transport and storage. Comparison of the amino-acid sequences of globins from Bacteria and Eukarya suggests that they share an early common ancestor, even though the proteins perform different functions in these two kingdoms. Until now, no members of the globin family have been found in the third kingdom, Archaea. Recent studies of biological signalling in the Bacteria and Eukarya have revealed a new class of haem-containing proteins that serve as sensors. Until now, no haem-based sensor has been described in the Archaea. Here we report the first myoglobin-like, haem-containing protein in the Archaea, and the first haem-based aerotactic transducer in the Bacteria (termed HemAT-Hs for the archaeon Halobacterium salinarum, and HemAT-Bs for Bacillus subtilis). These proteins exhibit spectral properties similar to those of myoglobin and trigger aerotactic responses.
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Wong ET, Jenne DE, Zimmer M, Porter SD, Gilks CB. Changes in chromatin organization at the neutrophil elastase locus associated with myeloid cell differentiation. Blood 1999; 94:3730-6. [PMID: 10572086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
Neutrophil elastase, proteinase-3, and azurocidin are primary components of neutrophil azurophilic granules and are encoded by closely linked genes (gene symbols ELA2, PRTN3, and AZU1, respectively) in a region of approximately 50 kb. These genes are coordinately expressed in a granulocyte-specific fashion, but the mechanisms defining this pattern of expression are unknown. To understand the role of chromatin organization in governing the expression of ELA2, PRTN3, and AZU1, we mapped this region of chromosome 19 and identified the adipsin (complement factor D) gene in proximity to the 3' end of ELA2. We then examined the changes in chromatin structure at the locus which accompany myeloid cell differentiation and identified 17 DNase I hypersensitive sites (DHS 1 to 17) in U-937 cells, an early myelomonocytic cell line expressing high levels of neutrophil elastase. Chemically induced differentiation and concomitant downregulation of AZU1, PRTN3, and ELA2 transcription in U-937 cells is not accompanied by changes in the DHS-pattern. Mature neutrophils, however, do not carry any of these hypersensitive sites, indicating a large degree of chromatin remodeling at this locus accompanying terminal granulocytic differentiation. Sixteen of the 17 DHS identified in U-937 cells are also present in the HL-60 myelomonocytic cell line. Hematopoietic cell lines representing the early erythroid and lymphocyte lineages, and a nonhematopoietic cell line display a subset of the hypersensitive sites. The altered chromatin structure specific to cells that actively transcribe the AZU1-PRTN3-ELA2 genes suggests that chromatin reorganization is an important mechanism regulating the myeloid-specific transcription of this gene cluster.
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Woytoń J, Zimmer M, Fuchs T. [The use of Gynipral (hexoprenaline) in suppression of uterus contractions]. Ginekol Pol 1999; 70:896-900. [PMID: 10715912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
OBJECTIVE The aim of of this study was to estimate the effectiveness and tolerance of Gynipral (hexoprenaline)-beta-2 sympathomimetic used as oral and intravenous tocolytic. MATERIAL AND METHODS We analysed 110 pregnant women admitted to the hospital with premature uterus contractions between 17 and 37 week of pregnancy. Pregnant women were divided into two groups. Group I--86 patients with regular uterus contractions. In this group Gynipral was administered to suppress uterus contractions. Group two consisted of 24 patients without regular uterus contractions. In this group women were treated with Gynipral to keep pregnant uterus in maximum relaxation in such cases as IUGR, oligohydramnion, after Strassman procedure before pregnancy or cerclage procedure in current pregnancy. Group I was treated with intravenous Gynipral infusion and after suppression of uterus contractions the way of administration was changed into oral. Group II from the beginning was treated with oral tocolysis with Gynipral. Pregnant women were continually under CTG control and all ailments such as tachycardia, flapping tremor and anxiety were analysed and noted. RESULTS Gynipral has effectively suppressed premature uterus contractions in 80 cases in group I (93%) and in 24 cases in group II (100%). In 106 cases (96%) patients have not presented any side effects. CONCLUSIONS Gynipral is an effective tocolytic successfully used in premature labor treatment. Gynipral has a good tolerance administered both intravenously and orally as well and in most cases there was no need to add antiarrhythmic drugs to reduce side effects.
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79
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Zimmer M. Dental surgeons in the early days of anaesthesia. DENTAL HISTORIAN : LINDSAY CLUB NEWSLETTER 1999:5-22. [PMID: 10825820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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80
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Woytoń J, Kłósek A, Zimmer M, Fuchs T. [Insulin-like growth factor binding protein 1 (IGFBP-1) in vaginal secretion as a marker of premature rupture of amniotic membranes]. Ginekol Pol 1999; 70:809-14. [PMID: 10736957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Diagnosis of premature rupture of amniotic membranes in premature pregnancy allows to estimate dangers which threaten foetus and pregnant woman and helps to put into practice the most accurate therapeutics procedures. The aim of this study was to prove the clinical usefulness of test detecting insulin-like growth factor binding protein-1 in vaginal secretion for diagnose of premature rupture of amniotic membranes and compare the sensiviteness and specificity the above test with Gram stained vaginal smears. We examined group of 50 pregnant women between 25 and 42 week of pregnancy treated in Department of Fertility and Obstetrics Medical University of Wrocław. Pregnant women were divided into 3 groups. In each of them both tests were performed to diagnose premature rupture of amniotic membranes. Achieved scores shows that Amni Check is specific and sensitive test detecting even insignificant premature rupture of amniotic membranes and has higher sensitivity comparing with common method used until now for detection of premature rupture of amniotic membranes based on Gramm stained vaginal secretion.
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81
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Chen Z, Zimmer M, Richkind K, Roherty S, Velasco J, Lytle C, Sandberg AA. Instability of the Ph chromosome in chronic myelocytic leukemia: a case report. CANCER GENETICS AND CYTOGENETICS 1999; 114:156-8. [PMID: 10549275 DOI: 10.1016/s0165-4608(99)00061-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
MESH Headings
- Aged
- Bone Marrow Cells/metabolism
- Bone Marrow Cells/pathology
- Centromere/genetics
- Chromosomes, Human, Pair 15/genetics
- Chromosomes, Human, Pair 22/genetics
- Disease Progression
- Genetic Variation/genetics
- Humans
- In Situ Hybridization, Fluorescence
- Karyotyping
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy
- Male
- Models, Genetic
- Philadelphia Chromosome
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Branchini BR, Magyar RA, Murtiashaw MH, Anderson SM, Helgerson LC, Zimmer M. Site-directed mutagenesis of firefly luciferase active site amino acids: a proposed model for bioluminescence color. Biochemistry 1999; 38:13223-30. [PMID: 10529195 DOI: 10.1021/bi991181o] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Under physiological conditions firefly luciferase catalyzes the highly efficient emission of yellow-green light from the substrates luciferin, Mg-ATP, and oxygen. In nature, bioluminescence emission by beetle luciferases is observed in colors ranging from green (approximately 530 nm) to red (approximately 635 nm), yet all known luciferases use the same luciferin substrate. In an earlier report [Branchini, B. R., Magyar, R. M., Murtiashaw, M. H., Anderson, S. M., and Zimmer, M. (1998) Biochemistry 37, 15311-15319], we described the effects of mutations at His245 on luciferase activity. In the context of molecular modeling results, we proposed that His245 is located at the luciferase active site. We noted too that the H245 mutants displayed red-shifted bioluminescent emission spectra. We report here the construction and purification of additional His245 mutants, as well as mutants at residues Lys529 and Thr343, all of which are stringently conserved in the beetle luciferase sequences. Analysis of specific activity and steady-state kinetic constants suggested that these residues are involved in luciferase catalysis and the productive binding of substrates. Bioluminescence emission spectroscopy studies indicated that point mutations at His245 and Thr343 produced luciferases that emitted light over the color range from green to red. The results of mutational and biochemical studies with luciferase reported here have enabled us to propose speculative mechanisms for color determination in firefly bioluminescence. An essential role for Thr343, the participation of His245 and Arg218, and the involvement of bound AMP are indicated.
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83
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Csiki C, Zimmer M. A molecular mechanical analysis of the active site of urease with a special emphasis on determining the binding conformations available to oxygen-bound urea. J Biomol Struct Dyn 1999; 17:121-31. [PMID: 10496427 DOI: 10.1080/07391102.1999.10508346] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
In order to model the active site of urease which contains two nickel ions with differing coordination geometries new parameters were derived for the AMBER* force field. These parameters were obtained by structure based optimization and use a single set of parameters with points on a sphere approach to model nickel(II) high-spin in all its coordination geometries. The force field was successfully used to model the active site of urease and to predict that a bridging water between the two nickel ions in urease was missing from the solid state structure of urease. A thorough conformational search was undertaken to find the conformations available to urea within urease. All the low energy conformations found were used to determine a consensus urea binding model.
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84
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Hauser W, Knobeloch KP, Eigenthaler M, Gambaryan S, Krenn V, Geiger J, Glazova M, Rohde E, Horak I, Walter U, Zimmer M. Megakaryocyte hyperplasia and enhanced agonist-induced platelet activation in vasodilator-stimulated phosphoprotein knockout mice. Proc Natl Acad Sci U S A 1999; 96:8120-5. [PMID: 10393958 PMCID: PMC22198 DOI: 10.1073/pnas.96.14.8120] [Citation(s) in RCA: 177] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Vasodilator-stimulated phosphoprotein (VASP), a substrate of cAMP- and cGMP-dependent protein kinases, is associated with focal adhesions, cell-cell contacts, microfilaments, and highly dynamic membrane regions. VASP, which is expressed in most cell types and in particularly high levels in human platelets, binds to profilin, zyxin, vinculin, F-actin, and the Listeria monocytogenes surface protein ActA. VASP is a member of the enabled (Ena)/VASP protein family and is thought to be involved in actin filament formation and integrin alphaIIbbeta3 inhibition in human platelets. To gain further insight into the in vivo function of this protein, VASP-deficient mice were generated by homologous recombination. VASP-/- mice demonstrated hyperplasia of megakaryocytes in bone marrow and spleen but exhibited no other macroscopic or microscopic abnormalities. Activation of platelets with thrombin induced a more than 2-fold higher surface expression of P-selectin and fibrinogen binding in VASP-deficient platelets in comparison to wild type. These data support the concept that VASP is a negative modulator of platelet and integrin alphaIIbbeta3 activation. Although the limited phenotypic differences between wild-type and VASP-/- mice suggested functional compensation of VASP by members of the Ena/VASP family, alterations in the expression levels of mammalian enabled (Mena) and Ena-VASP-like (Evl) protein were not detected. VASP-deficient mice may provide an interesting model system for diseases in which enhanced platelet activation plays a major role.
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85
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Cotroneo M, Zimmer M, Zegelin-Abt A. [Suggestions for the health care system of the future: family-oriented primary health care]. Pflege 1999; 12:163-71. [PMID: 10578903 DOI: 10.1024/1012-5302.12.3.163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This paper will describe one of the major trends in health care delivery: family oriented primary care. Implications and future directions for practice, education and research in the United States and Germany will be described and contrasted. The paper is a result of an ongoing dialogue between the first author, a Fulbright Professor at the University of Witten/Herdecke, and the second and third authors. The authors believe that, contextualizing emerging trends in health care delivery in this way, helps to clarify both what is unique to each country and what is actually or potentially shared in common.
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86
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Tomiałowicz M, Florjański J, Zimmer M, Kłósek A. [Results of surgical treatment of urinary stress incontinence women]. Ginekol Pol 1999; 70:141-6. [PMID: 10390916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
OBJECTIVES Analysis of early and late effects of surgical treatment at women suffering from the urinary stress incontinence. MATERIALS AND METHODS There were examined 52 patients treated surgically with urinary stress incontinence, and treated with perineoplasty (group I), treated with Marshall-Marchetti-Krantz procedure (group II), or both types of operations at the same time (group III). Early results of treatment were estimated at the 8th-10th day after surgical procedure, and late after two-eight years considering clinical and ultrasound examinations, and individual feelings of the patient. RESULTS A very good therapeutical effect of surgical treatment was obtained at 75% of patients, but the late one at 42% of patients. The early effect was the best within the group II (88%), whereas the late one within the group I, the worst results were obtained within the group III. The period between the procedure and repeated disorder was the longest within the group I. At women operated before menopause there were noted very good effects at 61% of them, but at those patients operated after menopause--at 38%, whereas the late repeated disorder often concerned the women operated before than after menopause (adequately 65 and 35%). CONCLUSION The treatment of the urinary stress incontinence employing perineoplasty compared with Marshall-Marchetti-Krantz procedure proved slighter risk of recurrence, slighter intensity and longer period without disorders. The application of both perineoplasty and Marshall-Marchetti-Krantz procedures simultaneously are more ineffective than of those procedures applied individually. Early effects of surgical treatment of urinary stress incontinence are better at patients operated before menopause, however more stable effect was noted at women operated after menopause.
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87
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Chuvpilo S, Zimmer M, Kerstan A, Glöckner J, Avots A, Escher C, Fischer C, Inashkina I, Jankevics E, Berberich-Siebelt F, Schmitt E, Serfling E. Alternative polyadenylation events contribute to the induction of NF-ATc in effector T cells. Immunity 1999; 10:261-9. [PMID: 10072078 DOI: 10.1016/s1074-7613(00)80026-6] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The transcription factor NF-ATc is synthesized in three prominent isoforms. These differ in the length of their C terminal peptides and mode of synthesis. Due to a switch from the use of a 3' polyA site to a more proximal polyA site, NF-ATc expression switches from the synthesis of the two longer isoforms in naive T cells to that of short isoform A in T effector cells. The relative low binding affinity of cleavage stimulation factor CstF-64 to the proximal polyA site seems to contribute to its neglect in naive T cells. These alternative polyadenylation events ensure the rapid accumulation of high concentrations of NF-ATc necessary to exceed critical threshold levels of NF-ATc for gene induction in effector T cells.
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88
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Branchini BR, Magyar RA, Murtiashaw MH, Anderson SM, Zimmer M. Site-directed mutagenesis of histidine 245 in firefly luciferase: a proposed model of the active site. Biochemistry 1998; 37:15311-9. [PMID: 9799491 DOI: 10.1021/bi981150d] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Firefly luciferase catalyzes the highly efficient emission of yellow-green light from substrate luciferin by a sequence of reactions that require Mg-ATP and molecular oxygen. We previously reported [Branchini, B. R., Magyar, R. A., Marcantonio, K. M., Newberry, K. J., Stroh, J. G., Hinz, L. K., and Murtiashaw, M. H. (1997) J. Biol. Chem. 272, 19359-19364] that 2-(4-benzoylphenyl)thiazole-4-carboxylic acid (BPTC), a firefly luciferin analogue, was a potent photoinactivation reagent for luciferase. We identified a luciferase peptide 244HHGF247, the degradation of which was directly correlated to the photooxidation process. We report here the construction and purification of wild-type and mutant luciferases H244F, H245F, H245A, and H245D. The results of photoinactivation and kinetic and bioluminescence studies with these proteins are consistent with His245 being the primary functional target of BPTC-catalyzed enzyme inactivation. The possibility that His245 is oxidized to aspartate during the photooxidation reaction was supported by the extremely low specific activity ( approximately 300-fold lower than WT) of the H245D mutant. Using the crystal structures of luciferase without substrates [Conti, E., Franks, N. P., and Brick, P. (1996) Structure 4, 287-298] and the functionally related phenylalanine-activating subunit of gramicidin synthetase 1 [Conti, E., Stachelhaus, T., Marahiel, M. A., and Brick, P. (1997) EMBO J. 16, 4174-4183] as a starting point, we have performed molecular-modeling studies and propose here a model for the luciferase active site with substrates luciferin and Mg-ATP bound. We have used this model to provide a structure-based interpretation of the role of 244HHGF247 in firefly bioluminescence.
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89
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Kortschak RD, Reimann H, Zimmer M, Eyre HJ, Saint R, Jenne DE. The human dead ringer/bright homolog, DRIL1: cDNA cloning, gene structure, and mapping to D19S886, a marker on 19p13.3 that is strictly linked to the Peutz-Jeghers syndrome. Genomics 1998; 51:288-92. [PMID: 9722953 DOI: 10.1006/geno.1998.5259] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Drosophila gene dead ringer (dri) was isolated as a novel gene encoding a sequence-specific DNA-binding protein. DRI is a founding member of a growing protein family whose members share a conserved DNA binding domain termed the A/T-rich interaction domain. dri is developmentally regulated, being expressed in a restricted set of cells including some neural cells and differentiating cells of the gut and salivary gland ducts. The mouse homolog of dri, bright, has been shown to be expressed in mature B-cells in the immune system, its product trans-activating expression through an IgH enhancer in transient transfection assays. We have cloned a human dri/bright homolog, termed DRIL1. Here we report the exon-intron structure of the gene and show physical linkage within 80 kb to the D19S886 marker on 19p13.3. As this marker is intimately linked to the Peutz-Jeghers syndrome in several large pedigrees, human dri (DRIL1) is a candidate gene for this disorder.
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90
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Zimmer M. The evolution of children's dentistry in Europe over the last 200 years. JOURNAL OF THE HISTORY OF DENTISTRY 1998; 46:3-11. [PMID: 9709659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Interest in better child oral health commenced during the 19th century, but modern children's dentistry started in 1902 when the first European dental clinic for children was opened in Strasbourg by Ernst Jessen. Although there were enormous changes in health systems after the Second World War, real changes in child dental care only occurred with the advent of WHO guidelines for the application of preventive programs.
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91
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Jenne DE, Reimann H, Nezu J, Friedel W, Loff S, Jeschke R, Müller O, Back W, Zimmer M. Peutz-Jeghers syndrome is caused by mutations in a novel serine threonine kinase. Nat Genet 1998; 18:38-43. [PMID: 9425897 DOI: 10.1038/ng0198-38] [Citation(s) in RCA: 845] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Peutz-Jeghers (PJ) syndrome is an autosomal-dominant disorder characterized by melanocytic macules of the lips, multiple gastrointestinal hamartomatous polyps and an increased risk for various neoplasms, including gastrointestinal cancer. The PJ gene was recently mapped to chromosome 19p13.3 by linkage analysis, with the highest lod score at marker D19S886. In a distance of 190 kb proximal to D19S886, we identified and characterized a novel human gene encoding the serine threonine kinase STK11. In a three-generation PJ family, we found an STK11 allele with a deletion of exons 4 and 5 and an inversion of exons 6 and 7 segregating with the disease. Sequence analysis of STK11 exons in four unrelated PJ patients has identified three nonsense and one acceptor splice site mutations. All five germline mutations are predicted to disrupt the function of the kinase domain. We conclude that germline mutations in STK11, probably in conjunction with acquired genetic defects of the second allele in somatic cells, cause the manifestations of PJ syndrome.
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92
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Elias M, Heimrath J, Zimmer M, Woytoñ J, Goluda M. Delayed interval delivery in a quintuplet pregnancy. Hum Reprod 1998; 13:224-6. [PMID: 9580192 DOI: 10.1093/humrep/13.1.224] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We present a case report of delayed delivery of a quintuplet pregnancy. The pregnancy resulted from intrauterine insemination following hormonal treatment. This case may represent the first report of quintuplets delivered using the technique of delayed interval delivery. Three separate spontaneous labours and one Caesarean section for two fetuses took place between the 24th and 32nd weeks of pregnancy. The delay between the first and the last delivery was 61 days. Only a boy, born fourth, survived.
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93
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Thiel A, Zimmer M, Stertmann WA, Kaps M, Hempelmann G. [Microembolizatoins during heart surgery under extracorporeal circulation]. Anasthesiol Intensivmed Notfallmed Schmerzther 1997; 32:715-20. [PMID: 9498087 DOI: 10.1055/s-2007-995141] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE By means of transcranial Doppler sonography (TCD), microembolic signals (MES) representing embolic events can be registered during cardiac surgery and extracorporeal circulation in a considerable number of patients. We conducted the present study to determine the neuro-psychiatric consequences of MES. METHODS 25 patients scheduled for elective aorto-coronary bypass grafting (ACBG; n = 10) or aortic valve replacement (AVR; n = 15) were studied pre- and postoperatively with neuropsychiatric testing. Results were related to the number of MES noted intraoperatively. In addition, we registered the intraoperative changes of middle cerebral artery blood flow velocity, mean arterial pressure, arterial blood gases, haemoglobin and haematocrit. Statistics included t-test, two-way analysis of variance, Mann-Whitney-U-test and Spearman correlation with p < 0.05 considered significant. RESULTS Regarding demographic data and intraoperative parameters, both study groups (ACBG vs. AVR) were comparable except for age. AVR patients showed significantly more MES than those undergoing ACBG (p < 0.012) which was most pronounced in the late state of surgery (aortic clamp off; p < 0.0003). However, MES counts did not correlate with neuropsychiatric test results. CONCLUSIONS In contrast to recent reports, we were unable to show a deterioration of postoperative neuropsychiatric state related to high intraoperative MES count in our patients. Future TCD studies should focus on the differentiation between gaseous emboli and particles even in the clinical setting, as the latter may well play a major role for the development of cerebral dysfunction following cardiac surgery and extracorporeal circulation.
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Zimmer M, Topp W. Homeostatic responses in the gut of Porcellio scaber (Isopoda: Oniscidea) optimize litter degradation. J Comp Physiol B 1997. [DOI: 10.1007/s003600050113] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Zimmer M. Surfactants in the gut fluids of Porcellio scaber (Isopoda: Oniscidea), and their interactions with phenolics. JOURNAL OF INSECT PHYSIOLOGY 1997; 43:1009-1014. [PMID: 12770472 DOI: 10.1016/s0022-1910(97)00074-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Fluids from the gut lumen of Porcellio scaber showed significantly reduced surface tension compared to a buffer solution. Tests with several dilutions indicated that the concentration of the surface active substances (surfactants) was about 80-fold higher than the 'critical micelle concentration'. Phenolics, e.g. gallotannins, when ingested in the diet increased the surface tension of the gut fluid, indicating reduced concentrations of free surfactants. The significance of gut surfactants in P. scaber, their role in digestive processes, and their interaction with tannins in this saprophagous soil arthropod are discussed.
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Jenne DE, Olsen AS, Zimmer M. The human guanidinoacetate methyltransferase (GAMT) gene maps to a syntenic region on 19p13.3, homologous to band C of mouse chromosome 10, but GAMT is not mutated in jittery mice. Biochem Biophys Res Commun 1997; 238:723-7. [PMID: 9325156 DOI: 10.1006/bbrc.1997.9992] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Guanindinoacetate methyltransferase (gene symbol, GAMT) catalyses the synthesis of creatine from guanidinoacetate and S-adensylmethionine. Pathological mutations in the coding region of GAMT were recently identified in two children with symptoms of muscular hypotonia, ataxia, seizures, and abnormal extrapyramidal movements. During contig construction in the telomeric region of human chromosome 19 we identified a cosmid clone carrying the entire GAMT gene. This clone was shown to overlap with cosmids from a contig that was previously mapped to chromosome 19p13.3. The human GAMT gene has a size of about 5 kb and consists of six exons which agree with the published cDNA sequence. Since the mouse mutations jittery/hesitant are located on band C of mouse chromosome 10 in a region of conserved synteny with 19p13.3 and jittery mice exhibit ataxia and abnormal movement behaviour, the genomic sequence of GAMT was determined in wild-type and jittery mice. The coding region of the GAMT gene, however, was not mutated in these mutant mice. Our linkage and sequence data will facilitate the identification of new GAMT mutations in patients suffering from an abnormal creatine metabolism.
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98
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Stöhr H, Zimmer M. [Wheelchair basketball from the orthopedic viewpoint]. SPORTVERLETZUNG SPORTSCHADEN : ORGAN DER GESELLSCHAFT FUR ORTHOPADISCH-TRAUMATOLOGISCHE SPORTMEDIZIN 1997; 11:109-15. [PMID: 9417650 DOI: 10.1055/s-2007-993376] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
155 (aged 16 to 52 years) wheelchair basketball players were surveyed to determine athletic injuries and overload-syndromes. During their active participation in wheelchair basketball 60.6% of the players have suffered 272 injuries and overload-syndromes. Those were mainly localised at the upper extremity (74.6%). Acute injuries predominate with 57.7%. Strains of the finger joint and skin injuries were found to be the most common injuries. Myogelosis and tendinosis were the most common reported overload-syndromes. A significantly higher number of complaints were associated with wheelchair basketball participation at league-level and depending on the player's position. At the end of the article the means of possible additional disability and consequences to specify therapy and prevention for disabled will be discussed.
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