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Busch S, Rosskopf D, Lang HJ, Weichert A, Siffert W. Expression, functional characterization and tissue distribution of a Na+/H+ exchanger cloned from Xenopus laevis oocytes (XL-NHE). Pflugers Arch 1998; 436:828-33. [PMID: 9799395 DOI: 10.1007/s004240050711] [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: 10/28/2022]
Abstract
We examined the functional properties of a Na+/H+ exchanger cloned from Xenopus laevis oocytes (XL-NHE) upon stable transfection into PS120 fibroblasts which lack endogenous Na+/H+ exchange. In contrast to untransfected cells, XL-NHE-transfected cells displayed Na+-dependent alkalinization upon acidification with nigericin. XL-NHE activity was inhibited by amiloride, ethylisopropylamiloride, HOE694 [(3-methylsulphonyl-4-piperidinobenzoyl)-guanidine methanesulphonate] and HOE642 [4-isopropyl-3-methylsulphonylbenzoyl)-guanidine methanesulphonate], Ki values being calculated at 5 micromol/l, 25 nmol/l, 300 nmol/l and 180 nmol/l, respectively. The Na+ dependence of pHi recovery was compatible with simple Michaelis-Menten kinetics, the Km for Na+ being 22.0+/-3.2 mmol/l and the Hill coefficient for Na+ being approximately 1. XL-NHE was activated by phorbol ester, whereas forskolin exerted no effect, suggesting the involvement of phospholipase C/protein kinase C signalling pathways rather than protein kinase A signalling pathways in XL-NHE stimulation. Using reverse transcription polymerase chain reaction, XL-NHE message could be detected in various Xenopus tissues including heart, brain, skeletal muscle, reticulocytes, A6-kidney cells and oocytes.
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Rosskopf D, Daelman W, Busch S, Schurks M, Hartung K, Kribben A, Michel MC, Siffert W. Growth factor-like action of lysophosphatidic acid on human B lymphoblasts. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 274:C1573-82. [PMID: 9611122 DOI: 10.1152/ajpcell.1998.274.6.c1573] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Proliferation and immunoglobulin secretion of B lymphocytes are regulated by specific antigens and numerous accessory immunomodulatory factors. Lysophosphatidic acid (LPA) is a glycerophospholipid mediator that is released from activated blood platelets, attains high levels in serum, and exerts potent stimulatory effects on, e.g., neutrophils, monocytes, and T lymphocytes. LPA is also generated by a secretory, cytokine-inducible phospholipase A2 present in high concentrations in inflammatory exudates and septic states. We investigated effects of LPA on human Epstein-Barr virus-immortalized B lymphoblasts, a model for immunoglobulin-secreting B cells. Intracellular Ca2+ was determined with fura 2 and the formation of inositol 1,4, 5-trisphosphate by anion-exchange chromatography. LPA stimulated an increase in inositol 1,4,5-trisphosphate levels and induced a transient rise in intracellular free Ca2+ concentration from 105 +/- 17 to 226 +/- 21 nM. This Ca2+ signal resulted from Ca2+ mobilization and Ca2+ influx and was subject to homologous desensitization. Pertussis toxin inhibited these responses by approximately 70%. Furthermore, LPA stimulated a 27.5% increase in guanosine 5'-O-(3-thiotriphosphate) binding to permeabilized B lymphoblasts, which suggests the direct activation of pertussis toxin-sensitive G proteins by LPA. LPA stimulated a strong increase in the specific phosphorylation of the mitogen-activated protein kinase (immunoblot analysis) that was prevented by the MEK inhibitor PD-98059. Finally, LPA triggered a 2-fold increase in DNA synthesis ([3H]thymidine incorporation) and a 2-fold increase in B lymphoblast number and evoked a 20- to 50-fold increase in immunoglobulin formation. By RT-PCR we detected specific mRNA transcripts for the recently cloned human LPA receptor. Thus our data suggest that LPA behaves as a B cell growth factor.
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Siffert W, Rosskopf D, Siffert G, Busch S, Moritz A, Erbel R, Sharma AM, Ritz E, Wichmann HE, Jakobs KH, Horsthemke B. Association of a human G-protein beta3 subunit variant with hypertension. Nat Genet 1998; 18:45-8. [PMID: 9425898 DOI: 10.1038/ng0198-45] [Citation(s) in RCA: 555] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hypertension is a common disorder of multifactorial origin that constitutes a major risk factor for cardiovascular events such as stroke and myocardial infarction. Previous studies demonstrated an enhanced signal transduction via pertussis toxin-sensitive G proteins in lymphoblasts and fibroblasts from selected patients with essential hypertension. We have detected a novel polymorphism (C825T) in exon 10 of the gene encoding the beta3 subunit of heterotrimeric G proteins (GNB3). The T allele is associated with the occurrence of a splice variant, GNB3-s (encoding G beta3-s), in which the nucleotides 498-620 of exon 9 are deleted. This in-frame deletion causes the loss of 41 amino acids and one WD repeat domain of the G beta subunit. By western-blot analysis, G beta3-s appears to be predominantly expressed in cells from individuals carrying the T allele. Significant enhancement of stimulated GTPgammaS binding to Sf9 insect cells expressing G beta3-s together with G alpha(i)2 and G gamma5 indicates that this splice variant is biologically active. Genotype analysis of 427 normotensive and 426 hypertensive subjects suggests a significant association of the T allele with essential hypertension.
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Busch S. Cloning and sequencing of the cDNA encoding for a Na+/H+ exchanger from Xenopus laevis oocytes (X1-NHE). BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1325:13-6. [PMID: 9106479 DOI: 10.1016/s0005-2736(97)00011-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have cloned and sequenced the cDNA for a Na+/H+ exchanger (NHE) from Xenopus laevis oocytes. This cDNA contains an open reading frame encoding a protein of 782 amino acids with 12 putative transmembrane domains and a long cytoplasmic tail. The protein exhibits a strong homology at the amino acid level to the human NHE-1 as well as to the beta NHE from trout red blood cells: 69% and 58% respectively. Two potential N-linked glycosylation sites at Asn56 and Asn351 were identified. Three potential protein kinase C phosphorylation sites at the cytoplasmic tail were identified at Ser494, Thr726 and Ser747. RT-PCR revealed the expression of the X1-NHE in Xenopus heart, reticulocytes and skeletal muscle.
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Busch S, Mill D, Pfaff AB. [Day care as a component of comprehensive health care structure after introduction of nursing care insurance]. DAS GESUNDHEITSWESEN 1997; 59 Suppl 1:55-8. [PMID: 9235131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Detailed time protocols based on direct observation as well as socio-demographic and morbidity-related data were collected in Day-Care-Facilities for the Aged and the Handicapped (Tagespflege), in order to gain information regarding the users and the service activities of these institutions. Women aged 80 years and over constitute the main users; they use the facilities between 8 am and 4.30 pm in most cases. The analysis of employee activities showed that roughly one quarter of the time was spent on specific services of such facilities, e.g. group activities, individual activating therapy of patients. Should Day-Care-Facilities play an (increasingly) important role in the domestic social service provision for the aged and the handicapped, the financing of their costs (on the average DM 88 per day, not counting transportation cost) must be reconsidered.
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Busch S, Huchler U, Pfaff AB. [Empirical analysis of work flow in inpatient nursing homes for the elderly]. DAS GESUNDHEITSWESEN 1997; 59 Suppl 1:42-8. [PMID: 9235128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The paper starts by offering a short overview of the state of implementation of the 2nd stage of the newly introduced German Long-Term-Care-Insurance (Pflegeversicherung). It continues to present results of a detailed descriptive analysis of employee activities in (long-term-care-)nursing-homes, differentiating by severity of the patients' condition. Surprisingly nurses spend a large part of their time (40%) on other than nursing activities. The time spent with individual patients varies considerably with sex and the main diagnosis; thus significantly more time is spent on (basic and treatment-related) nursing care for male patients. Age per se does not appear to influence the time required for taking care of a patient.
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Busch S. Carving-out mental health benefits to Medicaid beneficiaries: a shift toward managed care. ADMINISTRATION AND POLICY IN MENTAL HEALTH AND MENTAL HEALTH SERVICES RESEARCH 1997; 24:301-21. [PMID: 9217330 DOI: 10.1007/bf02042516] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Several states have designed and implemented innovative programs for Medicaid beneficiaries that carve-out the provision of mental health from general health care. This paper describes several such programs and outlines the choices states face in designing these services. Major decisions include the selection of a public or private agency, how that agency is chosen, reimbursement schemes, eligibility criteria, and benefits to be covered. While carve-out programs have yielded initial savings, more research is needed on their effect on quality of care and general health care costs.
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Pietruck F, Busch S, Virchow S, Brockmeyer N, Siffert W. Signalling properties of lysophosphatidic acid in primary human skin fibroblasts: role of pertussis toxin-sensitive GTP-binding proteins. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1997; 355:1-7. [PMID: 9007835 DOI: 10.1007/pl00004906] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have investigated the signalling properties of the naturally occurring intercellular signalling molecule lysophosphatidic acid (LPA) in primary human skin fibroblasts. LPA stimulated phospholipase C activity resulting in the formation of inositol 1,4,5-trisphosphate (IP3) which was accompanied by a concentration-dependent increase in intracellular calcium concentration ([Ca2+]i). The increase in [Ca2+]i was subject to homologous desensitisation but not to heterologous desensitisation by sphingosine-1-phosphate. The half-maximal effect of LPA on the rise in [Ca2+]i was attained at 7-20 nM. IP3 formation and Ca2+ mobilisation were highly pertussis toxin (PTX)-sensitive (100% and 75%, respectively). LPA also inhibited forskolin-stimulated formation of cAMP, which was partially reversed (51%) when fibroblasts were pretreated with PTX. To directly test the involvement of guanine nucleotide-binding regulatory proteins (G proteins), LPA-induced binding of the stable GTP analogue GTP gamma S was measured. LPA induced an increase in GTP gamma S binding, which was completely inhibited by PTX, implicating the involvement of Gi-type G proteins in LPA signalling. Furthermore, LPA increased DNA synthesis and cell proliferation. Finally, LPA induced the migration of human skin fibroblasts, which in conjunction with the stimulation of cell growth strengthens the presumed involvement of LPA in wound healing and tissue regeneration. Both effects (cell growth and migration) were almost completely PTX-sensitive. Overall, these investigations in primary cultures of human skin fibroblasts confirm and extend our knowledge about LPA signalling, suggesting a pivotal role of receptor coupled activation of Gi-type proteins at least in this cell type.
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Pietruck F, Moritz A, Montemurro M, Sell A, Busch S, Rosskopf D, Virchow S, Esche H, Brockmeyer N, Jakobs KH, Siffert W. Selectively enhanced cellular signaling by Gi proteins in essential hypertension. G alpha i2, G alpha i3, G beta 1, and G beta 2 are not mutated. Circ Res 1996; 79:974-83. [PMID: 8888689 DOI: 10.1161/01.res.79.5.974] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Recent studies have shown an enhanced signaling capacity of receptors coupled to pertussis toxin (PTX)-sensitive guanine nucleotide-binding proteins (G proteins) in immortalized B lymphoblasts from patients with essential hypertension. In the present study, we analyzed (1) whether such alterations would also be expressed in nontransformed cells of these individuals and (2) whether other G protein-mediated signaling pathways were also altered. Therefore, we established primary cultures of skin fibroblasts from previously characterized normotensive and hypertensive individuals (NT and HT cells, respectively). [Ca2+]i rises induced by lyso-phosphatidic acid (LPA), thrombin, and sphingosine-1-phosphate as well as the formation of inositol 1,4,5-trisphosphate and [3H]thymidine incorporation evoked by LPA were PTX sensitive and enhanced twofold in HT fibroblasts. In contrast, cellular responses induced by bradykinin, endothelin-1, and angiotensin II (all PTX insensitive) were similar in NT and HT cells. Formation of cAMP induced by stimulation of Gs with isoproterenol was identical in NT and HT cells. Western blot analysis yielded no evidence for an overexpression of G alpha i2, G alpha i3, G beta 2, and G beta 4. Furthermore, sequencing of cDNAs encoding for the ubiquitously expressed PTX-sensitive G protein subunits G alpha i2, G alpha i3, G beta 1, and G beta 2 from NT and HT cell lines yielded no evidence for mutations in these genes. Although the molecular mechanisms remain to be defined, these data support the concept of a selective enhancement of signal transduction via PTX-sensitive G proteins in essential hypertension.
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Pfaffenbach B, Adamek RJ, Hagemann D, Busch S, Hoffmann K, Altmeyer P, Schaffstein J, Wegener M. Effect of progressive systemic sclerosis on antral myoelectrical activity and gastric emptying. ZEITSCHRIFT FUR GASTROENTEROLOGIE 1996; 34:517-21. [PMID: 8873454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In patients with progressive systemic sclerosis (PSS) suffering from chronic dyspepsia the stomach may be affected by this disease. The objective of this study was to investigate both antral myoelectrical activity and gastric emptying in PSS patients. Electrogastrography (EGG) was performed in 17 PSS patients (16 female, one male, median age 58 years, range 32-74 years) with chronic dyspepsia. After an overnight fast during one hour in the fasting and one hour in the fed state after ingestion of a liquid-solid test meal (370 kcal; liquid phase labeled with 0.5 mCi 99mTc-colloid) antral electrical activity was measured by one pair of electrodes sonographically placed on the skin overlying the gastric antrum. Several EGG parameters including dominant frequency (DF), percentages of DF in the normal range (2-4 cycles per minute [cpm]), bradygastria (< 2 cpm) and tachygastria (4-10 cpm), dominant frequency instability coefficient (DFIC), and postprandial to preprandial power ratio (PR) were calculated. The data were correlated to results obtained in 20 age- and gender-matched healthy subjects. In addition, the data were compared to gastric retention of the radionuclide at 60 min measured by simultaneous scintigraphy. The PSS patients did not reveal electrical disturbances. They even exhibited a significant postprandial decrease in DFIC, bradygastria, and tachygastria (ns) compared to healthy subjects. Over 50% of the PSS patients showed a delayed gastric emptying. However, EGG did not correlate to radioscintigraphy significantly. Our results reflect an absent relationship between antral myoelectrical activity in EGG and gastric emptying. Therefore, electrogastrography is unsuitable to assess gastric involvement in PSS.
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Busch S, Wieland T, Esche H, Jakobs KH, Siffert W. G protein regulation of the Na+/H+ antiporter in Xenopus laevis oocytes. Involvement of protein kinases A and C. J Biol Chem 1995; 270:17898-901. [PMID: 7629094 DOI: 10.1074/jbc.270.30.17898] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We have characterized the regulation of the endogenous Na+/H+ exchanger in Xenopus laevis oocytes by G proteins and protein kinases by measuring the ethylisopropylamiloride-sensitive Li+ uptake. Injection of oocytes with the stable GTP analog GTP gamma S stimulated Li+ uptake up to almost 4-fold, an effect blocked by coinjection with the GDP analog, guanyl-5'-yl thiophosphate. Injection into oocytes of beta gamma subunits of the heterotrimeric G protein transducin enhanced Li+ uptake by about 3-fold. This stimulation was blocked by transducin alpha subunits, which by themselves did not influence Li+ uptake. Using various activators and inhibitors of protein kinases, it is demonstrated that the X. laevis oocyte Na+/H+ antiporter can be stimulated by activation of both protein kinase A and C. Stimulation of Na+/H+ exchanger activity by GTP gamma S but not that induced by transducin beta gamma subunits was blocked by the protein kinase A inhibitor H-89. On the other hand, transducin beta gamma subunit-stimulated activity was prevented by the protein kinase C inhibitor, calphostin C. The non-selective protein kinase inhibitor H-7 blocked both GTP gamma S- and transducin beta gamma subunit-stimulated Na+/H+ exchanger activity. The results suggest that the Na+/H+ exchanger of X. laevis oocytes can be activated by G proteins and that this activation is not direct but mediated by protein kinase A- and/or protein kinase C-dependent pathways.
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Busch S, Burckhardt BC, Siffert W. Expression of the human sodium/proton exchanger NHE-1 in Xenopus laevis oocytes enhances sodium/proton exchange activity and establishes sodium/lithium countertransport. Pflugers Arch 1995; 429:859-69. [PMID: 7603840 DOI: 10.1007/bf00374811] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We investigated whether the human sodium/proton (Na+/H+) exchanger isoform 1 (NHE-1) can mediate sodium/lithium (Na+/Li+) countertransport. Using the Xenopus laevis oocyte expression system we determined amiloride-sensitive Li+ uptake, a measure of Na+/H+ exchange, in oocytes injected with water or NHE-1 cRNA. Amiloride-sensitive Li+ uptake was three- to tenfold enhanced over control in NHE-1 cRNA-injected cells and was selectively inhibited by 0.01 microM HOE 694 [i.e. (3-methylsulphonyl-4-piperidinobenzoyl) guanidine methanesulphonate]. The endogenously present Na+/H+ exchanger was insensitive to HOE 694. After acidification of oocytes from pH 7.7 to 6.8, amiloride-sensitive Li+ uptake was four- to tenfold higher in NHE-1 cRNA-injected cells than in controls. Li+ efflux from control oocytes was independent of extracellular Na+, indicating that these cells expressed no measurable Na+/Li+ countertransport activity. In NHE-1 cRNA-injected oocytes, Li+ efflux was distinctly enhanced by extracellular Na+ ions. This Na(+)-dependent Li+ efflux was inhibited by ethylisopropylamiloride, phloretin and by cytosolic acidification. The data show that expression of the NHE-1 in X. laevis oocytes induces the expression of Na+/Li+ countertransport. The data confirm that Na+/H+ exchange and Na+/Li+ countertransport are mediated by the same transport system.
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Busch S, Altmeyer P. [Schimmelpenning-Feuerstein-Mims syndrome (SFM syndrome)]. DER HAUTARZT 1994; 45:719-21. [PMID: 8002342 DOI: 10.1007/s001050050157] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We report on the case of a 70-year-old caucasian woman with a large linear sebaceous naevus with multifocal intralesional basaliomas and a lipodermoid of the left eye. This rare finding has been preserved because of the special history of the patient. The naevus spread on the left side from parietal to retroauricular, nuchal and sternal. Because of the patient's cardio-pulmonary insufficiency we excised the basaliomas under local anaesthesia. We also made a partial stripped excision of the left-sided parietal parts of the naevus.
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van den Berg AA, van Lenthe H, Busch S, de Korte D, van Kuilenburg AB, van Gennip AH. The roles of uridine-cytidine kinase and CTP synthetase in the synthesis of CTP in malignant human T-lymphocytic cells. Leukemia 1994; 8:1375-8. [PMID: 8057676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The pattern of incorporation of [14C]uridine showed that in MOLT-3 cells an increased proportion of CTP was synthesized via CTP synthetase, compared to proliferating normal human T lymphocytes at a physiological concentration of cytidine (< 0.5 microM). Furthermore, in the proliferating normal human T lymphocytes similar patterns of incorporation of [14C]uridine were observed in the presence of the physiological concentration of cytidine and after addition of 2 microM of cytidine. In contrast, in the MOLT-3 cells after addition of 2 microM of cytidine the proportion of CTP synthesized by conversion of UTP into CTP was substantially decreased, whereas the salvage of cytidine was proportionally increased. We conclude that the reutilization of uridine is a preferred route in the synthesis of CTP for MOLT-3 cells at physiological concentrations of uridine and cytidine, whereas in proliferating normal human T lymphocytes CTP is largely synthesized through reutilization of cytidine. This difference in salvage of pyrimidine ribonucleosides may be exploited for selective chemotherapy.
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Vogel A, Busch S, Jungnickel K, Birngruber R. Mechanisms of intraocular photodisruption with picosecond and nanosecond laser pulses. Lasers Surg Med 1994; 15:32-43. [PMID: 7997046 DOI: 10.1002/(issn)1096-910110.1002/lsm.v15:110.1002/lsm.1900150106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Nd:YAG laser photodisruption with nanosecond (ns) pulses is an established method for intraocular surgery. In order to assess whether an increased precision can be achieved by the use of picosecond (ps) pulses, the plasma size, the shock wave characteristics, and the cavitation bubble expansion after optical breakdown with ps- and ns-laser pulses were investigated by time-resolved photography and acoustic measurements. Nd:YAG laser pulses with a duration of 30 ps and 6 ns, respectively, were focused into a water-filled glass cuvette. Frequency doubled light from the same laser pulses was optically delayed between 2 ns and 136 ns and used as illumination light source for photography. Since the individual events were well reproducible, the shock wave and bubble wall position could be determined as a function of time. From the slope of these r(t) curves, the shock wave and bubble wall velocities were determined, and the shock wave pressure was calculated from the shock velocity. The plasma size at various laser pulse energies was measured from photographs of the plasma radiation. The breakdown thresholds at 30 ps and 6 ns pulse duration were found to be 15 microJ and 200 microJ, respectively. At threshold, ps-plasmas are shorter than ns-plasmas, but at the same pulse energy they are always approximately 2.5 times longer. The initial shock pressures were 17 kbar after ps-pulses with an energy of 50 microJ, and 21 kbar after 1 mJ ns-pulses. The pressure amplitude decayed much faster after the ps-pulses. The maximum expansion velocity of the cavitation bubble was 350 m/s after a 50 microJ ps-pulse, but 1,600 m/s after a 1 mJ ns-pulse. The side effects of intraocular microsurgery associated with shock wave emission and cavitation bubble expansion can be considerably reduced by the use of ps-pulses, and new applications of photodisruption may become possible.
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Vogel A, Busch S, Jungnickel K, Birngruber R. Mechanisms of intraocular photodisruption with picosecond and nanosecond laser pulses. Lasers Surg Med Suppl 1994; 15:32-43. [PMID: 7997046 DOI: 10.1002/lsm.1900150106] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Nd:YAG laser photodisruption with nanosecond (ns) pulses is an established method for intraocular surgery. In order to assess whether an increased precision can be achieved by the use of picosecond (ps) pulses, the plasma size, the shock wave characteristics, and the cavitation bubble expansion after optical breakdown with ps- and ns-laser pulses were investigated by time-resolved photography and acoustic measurements. Nd:YAG laser pulses with a duration of 30 ps and 6 ns, respectively, were focused into a water-filled glass cuvette. Frequency doubled light from the same laser pulses was optically delayed between 2 ns and 136 ns and used as illumination light source for photography. Since the individual events were well reproducible, the shock wave and bubble wall position could be determined as a function of time. From the slope of these r(t) curves, the shock wave and bubble wall velocities were determined, and the shock wave pressure was calculated from the shock velocity. The plasma size at various laser pulse energies was measured from photographs of the plasma radiation. The breakdown thresholds at 30 ps and 6 ns pulse duration were found to be 15 microJ and 200 microJ, respectively. At threshold, ps-plasmas are shorter than ns-plasmas, but at the same pulse energy they are always approximately 2.5 times longer. The initial shock pressures were 17 kbar after ps-pulses with an energy of 50 microJ, and 21 kbar after 1 mJ ns-pulses. The pressure amplitude decayed much faster after the ps-pulses. The maximum expansion velocity of the cavitation bubble was 350 m/s after a 50 microJ ps-pulse, but 1,600 m/s after a 1 mJ ns-pulse. The side effects of intraocular microsurgery associated with shock wave emission and cavitation bubble expansion can be considerably reduced by the use of ps-pulses, and new applications of photodisruption may become possible.
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van den Berg AA, van Lenthe H, Busch S, de Korte D, Roos D, van Kuilenburg AB, van Gennip AH. Evidence for transformation-related increase in CTP synthetase activity in situ in human lymphoblastic leukemia. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 216:161-7. [PMID: 8365402 DOI: 10.1111/j.1432-1033.1993.tb18128.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
To determine the role of the enzyme CTP synthetase (EC 6.3.4.2) in the synthesis in situ of CTP in normal and in malignant lymphoblastic cells, the metabolism of radiolabeled pyrimidine ribonucleosides was studied in proliferating normal T lymphocytes and was compared with that of proliferating MOLT-3 cell-line cells and differentiated (non-proliferating) MOLT-3 cells. Both the incorporation of [14C]uridine into UTP and CTP and the incorporation of [14C]cytidine in CTP, as well as the fluxes of these labeled nucleosides through the nucleotide pools into nucleic acids, were elevated in proliferating MOLT-3 cells compared to proliferating T lymphocytes. Furthermore, the conversion of UTP into CTP was enhanced in proliferating MOLT-3 cells compared to proliferating T lymphocytes, indicating a higher activity of CTP synthetase in the leukemic cells. In non-proliferating MOLT-3 cells, the pyrimidine ribonucleotide fluxes were decreased compared to proliferating MOLT-3 cells and proliferating T lymphocytes. However, the decreased ratio of uracil/cytosine ribonucleotides that was found in proliferating T lymphocytes and proliferating MOLT-3 cells compared to non-proliferating blood lymphocytes, was preserved in the differentiated MOLT-3 cells. Moreover, although the fluxes had decreased, most CTP was still synthesized by CTP synthetase in the differentiated MOLT-3 cells. Thus, the elevated activity of CTP synthetase in MOLT-3 cells was independent of the cell growth and maturation stage. We conclude that the increased activity of CTP synthetase is associated with the process of malignant transformation in MOLT-3 cells. Therefore, CTP synthetase offers an attractive target for selective therapy in human acute T-lymphoid leukemia.
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van Gennip AH, Busch S, Elzinga L, Stroomer AE, van Cruchten A, Scholten EG, Abeling NG. Application of simple chromatographic methods for the diagnosis of defects in pyrimidine degradation. Clin Chem 1993; 39:380-5. [PMID: 8448846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Recent findings suggest that inborn errors of pyrimidine catabolism are less rare than generally assumed. We propose a complete set of diagnostic methods for these disorders, suitable for the clinical chemistry laboratory, and present relevant reference data. Applications of thin-layer chromatography, high-performance liquid chromatography, and conventional cation-exchange amino acid analysis lead to detection of various defects in pyrimidine degradation, including the recently described deficiencies of dihydropyrimidine dehydrogenase and dihydropyrimidinase. We also illustrate the potential of the methods to analyze for the catabolites expected to be increased in the urine of patients with ureidopropionase deficiency. Possible pitfalls in the diagnosis and ways to prevent misdiagnosis are demonstrated. The methods offer possibilities for clinical chemistry laboratories to extend their diagnostic capacity to the new area of pyrimidine degradation defects.
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van Gennip AH, Busch S, Elzinga L, Stroomer AE, van Cruchten A, Scholten EG, Abeling NG. Application of simple chromatographic methods for the diagnosis of defects in pyrimidine degradation. Clin Chem 1993. [DOI: 10.1093/clinchem/39.3.380] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Recent findings suggest that inborn errors of pyrimidine catabolism are less rare than generally assumed. We propose a complete set of diagnostic methods for these disorders, suitable for the clinical chemistry laboratory, and present relevant reference data. Applications of thin-layer chromatography, high-performance liquid chromatography, and conventional cation-exchange amino acid analysis lead to detection of various defects in pyrimidine degradation, including the recently described deficiencies of dihydropyrimidine dehydrogenase and dihydropyrimidinase. We also illustrate the potential of the methods to analyze for the catabolites expected to be increased in the urine of patients with ureidopropionase deficiency. Possible pitfalls in the diagnosis and ways to prevent misdiagnosis are demonstrated. The methods offer possibilities for clinical chemistry laboratories to extend their diagnostic capacity to the new area of pyrimidine degradation defects.
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Abstract
CApillary zone electrophoresis was tested for its suitability for studying protein-drug binding. Three methods were investigated, viz., the Hummel-Dreyer method, the vacancy peak method and frontal analysis. Frontal analysis appeared to be the preferred method.
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123
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Busch S, Lehman B. Standards bring the vision closer to reality. COMPUTERS IN HEALTHCARE 1992; 13:56, 58. [PMID: 10116602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
A large multi-entity health system in the Midwest now processes more than 150,000 electronic claims each year. With industry-wide standards for EMC formats and edits, Franciscan Health System looks to significantly increase that number with a commensurate increase in billing efficiency.
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124
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Cowan MJ, Burr RL, Narayanan SB, Buzaitis A, Strasser M, Busch S. Comparison of autoregression and fast Fourier transform techniques for power spectral analysis of heart period variability of persons with sudden cardiac arrest before and after therapy to increase heart period variability. J Electrocardiol 1992; 25 Suppl:234-9. [PMID: 1297703 DOI: 10.1016/0022-0736(92)90109-d] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Clinical studies have used two types of analysis of the power spectral estimates of heart period variability: autoregressive and fast Fourier transform techniques. Controversy exists regarding which method is the most valid. The specific aims of this study are: (1) to describe the power spectra of heart period variability before and after an intervention designed to increase heart period variability in persons after sudden cardiac arrest; (2) to compare the integral of power spectral density between autoregressive and fast Fourier transform techniques within low and high-frequency bands; (3) to compare the magnitude of the spectral peak values determined by autoregressive and fast Fourier transform techniques approaches within low and high-frequency bands; and (4) to compare the aforementioned parameters using 4-minute, 1-hour, and 24-hour blocks of heart period data. Results indicated high correlations between spectral estimations by autoregressive and fast Fourier transform techniques using integrals or peak values within either the low or high-frequency ranges. The autoregressive technique demonstrated better resolution of sharp peaks than the fast Fourier transform technique, and makes a smoother, more interpretable curve. Lastly, people can cognitively change their heart rate variability.
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125
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van Gennip AH, Busch S, Scholten EG, Stroomer LE, Abeling NG. Simple method for the quantitative analysis of dihydropyrimidines and N-carbamyl-beta-amino acids in urine. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1991; 309B:15-9. [PMID: 1781359 DOI: 10.1007/978-1-4615-7703-4_4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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126
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Busch S, Pangert R, Müller W, Richartz G. [Follow-up of hearing damage in a metallurgy industry]. ZEITSCHRIFT FUR DIE GESAMTE HYGIENE UND IHRE GRENZGEBIETE 1987; 33:241-3. [PMID: 3617831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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127
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Rikli R, Busch S. Motor performance of women as a function of age and physical activity level. JOURNAL OF GERONTOLOGY 1986; 41:645-9. [PMID: 3745821 DOI: 10.1093/geronj/41.5.645] [Citation(s) in RCA: 101] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In Study 1, simple and choice reaction time, balance, sit and reach flexibility, shoulder flexibility, and grip strength of older active women were compared with older inactive women, and active and inactive younger women. Except for grip strength, scores of older active women on all measures were significantly better than for older inactive women, and much more like those of the younger women. In Study 2, scores of avid women golfers were compared with the older active and inactive women from Study 1. On all variables, the scores of golfers were significantly better than those of the older inactive women, but not significantly different from the older active women. Findings were consistent with previous research on men, indicating that motor performance tends to be more highly related to lifelong physical activity level than to age.
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128
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Garbrecht M, Busch S, Langenbuch T, Ziemer G. Treatment of soloid tumors and acute leukemias with the polyamine antimetabolites difluoromethylornithine and methylglyoxal bis (guanylhydrazone). J Cancer Res Clin Oncol 1986. [DOI: 10.1007/bf02579846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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129
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Busch S. [Preparation of a gingival mask]. DAS DENTAL-LABOR. LE LABORATOIRE DENTAIRE. THE DENTAL LABORATORY 1984; 32:793-5. [PMID: 6592110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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130
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Schulz V, Busch S, Endres P, Rubin R, Schönen M. [Polychemotherapy of inoperable bronchogenic carcinoma: preliminary results (author's transl)]. PRAXIS UND KLINIK DER PNEUMOLOGIE 1979; 33 Suppl 1:660-1. [PMID: 88732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Preliminary results indicate that BACO and SAKK are capable of inducing remission in 80-90% of cases of small-cell bronchogenic carcinoma; these remissions last for about 6 months and not only prolong, but improve the quality of, life. In view of the small number of cases so far observed no assessment can as yet be made of the superiority of one or the other method concerning the incidence and duration of remissions and survival time. In cases of squamous cell cancer the two therapeutic methods succeeded in only 30-40% of the patients in inducing partical remissions and they did not appear to improve the quality of life. The question whether the treatment actually prolongs life as compared with the natural course of the disease remains open.
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131
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Busch S, Kern F, Schulz V. [Early diagnosis of small airways disease in young smokers (author's transl)]. PRAXIS UND KLINIK DER PNEUMOLOGIE 1979; 33 Suppl 1:651-4. [PMID: 461361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Investigations during the past years have established that determinations of closing volume, flow-volume curves and frequency-dependent compliance are capable of detecting pathological changes in the bronchial system at a time when the customary lung function tests (FEV1.0 resistance as measured by bodyplethysmography) are still normal. These observations have been made use of to diagnose incipient damage in persons exposed to bronchial noxae. In the present investigation the effect of smoking on the airways was studied in a group of 25 persons aged 20-25 years by determining the closing volume and differences in ventilatory distribution (Thews method). The results were compared with those obtained in a group of 27 non-smokers in the same age group.
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132
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Sherwood WC, Glackin K, Busch S, Dahlke D. The standardization of blood bank antisera with the Groupamatic 360 C system. REVUE FRANCAISE DE TRANSFUSION ET IMMUNO-HEMATOLOGIE 1978; 21:311-20. [PMID: 97752 DOI: 10.1016/s0338-4535(78)80066-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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133
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Busch S, Korting GW. [Lepromatous leprosy]. DIE MEDIZINISCHE WELT 1977; 28:1561-3. [PMID: 927110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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134
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Schnabel KH, Schulz V, Busch S, Just H. [Drug-induced primary vascular pulmonary hypertension. Contribution to its etiology and clinical course]. DIE MEDIZINISCHE WELT 1976; 27:1300-3. [PMID: 933821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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135
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Dargel D, Hock A, Busch S. [Effect of the biological value of dietary proteins on phospholipids in bones]. DIE NAHRUNG 1973; 17:517-25. [PMID: 4723604 DOI: 10.1002/food.19730170414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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136
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Strohm PL, Busch S. Comparison of effectiveness of various proteolytic enzymes in blood-group antibody detection. Transfusion 1969; 9:93-7. [PMID: 5767408 DOI: 10.1111/j.1537-2995.1969.tb04924.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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137
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Yam LT, Rudzki C, Busch S, Leithold SL. Ovarian neoplasm associated with autoimmune hemolytic anemia. Am J Obstet Gynecol 1966; 95:207-11. [PMID: 5935704 DOI: 10.1016/0002-9378(66)90170-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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