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Hahn T, Wolff SN, Czuczman M, Fisher RI, Lazarus HM, Vose J, Warren L, Watt R, McCarthy PL. The role of cytotoxic therapy with hematopoietic stem cell transplantation in the therapy of diffuse large cell B-cell non-Hodgkin's lymphoma: an evidence-based review. Biol Blood Marrow Transplant 2002; 7:308-31. [PMID: 11464975 DOI: 10.1016/s1083-8791(01)80003-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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152
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Enke D, Friedel F, Janowski F, Hahn T, Gille W, Müller R, Kaden H. Ultrathin porous glass membranes with controlled texture properties. CHARACTERIZATION OF POROUS SOLIDS VI, PROCEEDINGS OF THE 6TH INTERNATIONAL SYMPOSIUM ON THE CHARACTERIZATION OF POROUS SOLIDS (COPS-VI) 2002. [DOI: 10.1016/s0167-2991(02)80154-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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153
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Lang I, Hoffmann C, Olip H, Pabst MA, Hahn T, Dohr G, Desoye G. Differential mitogenic responses of human macrovascular and microvascular endothelial cells to cytokines underline their phenotypic heterogeneity. Cell Prolif 2001; 34:143-55. [PMID: 11380484 PMCID: PMC6496340 DOI: 10.1046/j.1365-2184.2001.00205.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A variety of growth factors promote the complex multistep process of angiogenesis. The mitogenic activity of vascular endothelial growth factors (VEGFs) and placental growth factors (PlGFs), known as cytokines acting predominantly on endothelial cells, was tested on human umbilical vein endothelial cells (HUVEC) and microvascular endothelial cells (MIEC) and compared with the potency of the universally acting basic fibroblast growth factor (FGF-2). The cells were seeded at different cell numbers and incubated with various doses of growth factors for a period of 24-72 h in culture medium +/- serum. Proliferation was determined by measuring the optical density after staining the cells with the tetrazolium salt WST-1. VEGF121 and VEGF165 increased the number of HUVEC and MIEC at low and high seeding densities various doses and incubation times. The efficiency of FGF-2 was less pronounced at high seeding densities of the cells under serum-free conditions. PlGF-1 and PlGF-2 stimulated mitogenesis on HUVEC only at low cell numbers and after a short incubation time by 125 +/- 3% and 102 +/- 5% (P < 0.001), respectively. Longer incubation times with the lower seeding density in the absence of FCS did not induce a significant stimulatory effect of the PlGFs. MIEC responded stronger to all growth factors. In particular under serum free conditions, PlGF-1 and PlGF-2 effectively stimulated cell proliferation by 247 +/- 54% (P < 0.01) and 288 +/- 40% (P < 0.05) at low cell numbers, and by 81 +/- 13% (P < 0.05) and 49 +/- 13% (P < 0.01), respectively, at high cell numbers. The addition of fetal calf serum caused a reduced proliferative response of all growth factors on both cell types related to the controls. In conclusion, MIEC and HUVEC differ in their proliferative response to VEGFs, PlGFs and FGF-2.
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154
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Matala E, Hahn T, Yedavalli VR, Ahmad N. Biological characterization of HIV type 1 envelope V3 regions from mothers and infants associated with perinatal transmission. AIDS Res Hum Retroviruses 2001; 17:1725-35. [PMID: 11788024 DOI: 10.1089/08892220152741423] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Our previous study has shown that the human immunodeficiency virus type 1 (HIV-1) envelope V3 region minor genotypes of infected mothers were transmitted to their infants and predominated initially as a homogeneous virus population in the infants (Ahmad N, Baroudy BM, Baker RC, et al.: J Virol 1995;69:1001-1012). Here we have characterized the biological properties, including cellular tropism, replication efficiency, cytopathic effects, and coreceptor utilization, of these V3 region isolates from mothers and infants. Nineteen V3 region sequences from three mother-infant pairs, including the minor variants of mothers and the major variants of infants as characterized in our previous study, were reciprocally inserted into an HIV-1 infectious molecular clone, pNL4-3, and chimeric viruses were generated by DNA transfections into HeLa cells. Equal amounts of chimeric viruses were then used to infect T lymphocyte cell lines (A3.01 and MT-2), primary blood lymphocytes (PBLs), primary monocyte-derived macrophages (MDMs), and coreceptor cell lines. We found that the V3 region chimeras failed to replicate in T lymphocyte cell lines but replicated in MDMs and PBLs, albeit at reduced levels compared with R5 laboratory HIV-1 strains. In addition, the V3 region chimeras were able to infect the HOS-CD4(+)CCR5(+) cell line, suggesting CCR5 coreceptor utilization. Moreover, the V3 region chimeras were unable to induce syncytia in MT-2 cells, indicative of non-syncytium-inducing (NSI) phenotypes. In conclusion, the HIV-1 minor genotypes of infected mothers with macrophage-tropic and NSI or R5 phenotypes are transmitted to their infants and are initially maintained with the same properties.
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155
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Hahn T, Ahmad N. Genetic characterization of HIV type 1 gag p17 matrix genes in isolates from infected mothers lacking perinatal transmission. AIDS Res Hum Retroviruses 2001; 17:1673-80. [PMID: 11779356 DOI: 10.1089/088922201753342095] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The gag p17 matrix sequences of human immunodeficiency virus type 1 (HIV-1) were analyzed from three nontransmitting mothers (mothers who failed to transmit HIV-1 to their infants in the absence of antiretroviral therapy), including multiple deliveries in the case of mother 3. There was a low degree of heterogeneity of gag p17 matrix sequences in nontransmitting mothers compared with our previously analyzed mother-infant pairs' sequences. Whereas most of the functional domains essential for p17 matrix function were generally conserved, the polymerization site was less conserved. Several amino acid motifs, including KIEEEQN (positions 103-109) at the major antibody-binding site, were variable and the C-terminal 6-mer QVSQNY, a lysine or glutamine at position 15, an alanine at position 54, a lysine at position 76, a valine at position 104, and an aspartic acid at positions 102 and 121 were conserved in nontransmitting mothers' sequences compared with transmitting mothers' sequences. Phylogenetic analyses of 82 p17 matrix sequences revealed distinct clusters for each nontransmitting mother. Some of these motifs in gag p17 matrix sequences that are present in nontransmitting mothers and absent in transmitting mothers could be used as new targets for the development of preventive strategies for perinatal transmission.
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156
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Arikan G, Reich O, Weiss U, Hahn T, Reinisch S, Tamussino K, Pickel H, Desoye G. Are endometrial carcinoma cells disseminated at hysteroscopy functionally viable? Gynecol Oncol 2001; 83:221-6. [PMID: 11606075 DOI: 10.1006/gyno.2001.6380] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate the rate of transtubal dissemination of endometrial carcinoma cells by hysteroscopy and the functional viability of disseminated tumor cells by assessing cell adhesion in an in vitro model. METHODS We studied 24 uteri obtained at TAH+BSO in patients with endometrial carcinoma. Further inclusion criteria were negative peritoneal cytology, no involvement of the uterine serosa or extrauterine disease, and endometrial surface involvement >1 cm in diameter. In vitro fluid hysteroscopy was performed with a 5-mm single-flow rigid hysteroscope. A maximum of 150 ml saline was infused at a maximum pressure of 100 mm Hg for a maximum of 3 min. Fluid running off through the tubes was collected. The cell suspension was enriched by a density gradient centrifugation. The isolated cells had a mean viability of 90% as judged by trypan blue exclusion. Viable cells (5 x 10(4) per 2-cm(2) polyvinyl chloride well plate) were cultured with equal parts of Dulbecco's modified Eagle's minimal essential medium and Ham's F-12 for 24 h. The endpoint of the analysis was the adherence of tumor cells to the polyvinyl chloride well plate, which was taken as a proxy for functional cell viability. Cytological evaluation was performed separately by two cytologists blinded to the source and date of the smears. RESULTS Transtubal fluid dissemination was seen in 20 of 24 (83%) uteri. Tumor cells were found in 17 specimens (71%). In 10 (42%) specimens the disseminated tumor cells were functionally viable. CONCLUSIONS Our model suggests that hysteroscopy can cause dissemination of malignant cells into the abdominal cavity from uteri containing endometrial carcinoma and that these cells can be functionally viable and adhere to a matrix.
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Korgun ET, Demir R, Hammer A, Dohr G, Desoye G, Skofitsch G, Hahn T. Glucose transporter expression in rat embryo and uterus during decidualization, implantation, and early postimplantation. Biol Reprod 2001; 65:1364-70. [PMID: 11673251 DOI: 10.1095/biolreprod65.5.1364] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Efficient transfer of glucose from the mother to the embryonic compartment is crucial to sustain the survival and normal development of the embryo in utero, because the embryo's production of this primary substrate for oxidative metabolism is minimal. In the present study, the temporal sequence of expression of the sodium-independent facilitative glucose transporter isoforms GLUTs 1, 3, 4, and 5 was investigated in the developing rat uteroembryonic unit between conception and Gestational Day 8 using immunohistochemistry. The GLUTs 1, 3, and 4 were expressed in the embryonic tissues after the start of implantation, being colocalized in the parietal endoderm, visceral endoderm, primary ectoderm, extraembryonic ectoderm, and the ectoplacental cone. In the uterus, a faint GLUT1 labeling emerged, but not until Gestational Day 3, in the luminal epithelium, endometrial stroma, and decidual cells. The intensity of GLUT1 staining increased in the latter population with progressing decidualization. Endometrial glands and myometrial smooth muscle cells stained neither for GLUT1 nor for GLUT3 until postimplantation. During all developmental stages examined, GLUT4 was visualized throughout the pregnant rat uterus, as was GLUT3 (with the above-mentioned exceptions). The density of GLUT5 was generally less than the sensitivity of the immunohistochemical detection method in all tissues investigated. In conclusion, the data point to a significant expression of the high-affinity glucose transporters GLUTs 1, 3, and 4 in the rat uteroembryonic unit, providing supportive evidence for an important role of facilitative glucose diffusion during peri-implantation development.
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Barash J, Pirogovski A, Livneh A, Brezniak N, Dror Y, Hahn T. Colchicine treatment in familial Mediterranean fever: an indirect effect on in vitro serum amyloid A secretion via leukocyte derived factors. Clin Exp Rheumatol 2001; 19:S76. [PMID: 11760407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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159
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Hahn T, Foldspang A, Ingemann-Hansen T. Prevalence of knee instability in relation to sports activity. Scand J Med Sci Sports 2001; 11:233-8. [PMID: 11476429 DOI: 10.1034/j.1600-0838.2001.110407.x] [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: 11/23/2022]
Abstract
The objective was to estimate the prevalence of knee instability among active athletes and to investigate potential associations to type, amount and duration of sports participation. Based on a questionnaire, 339 athletes provided information about different features of occupation, sports activity and knee instability. The 12-month period prevalence of knee instability and constant or recurrent knee instability, and absence from sport and absence from work due to knee instability, was 22%, 14%, 5% and 1%, respectively. Knee instability as such, and constant or recurrent knee instability were found to be positively associated with female gender and different features of occupational work. In conclusion, knee instability is a commonly reported phenomenon among active athletes. It was found to be independent of the type and the amount of sports activity but highly dependent on female gender, type and amount of occupational work.
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160
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Hahn T, Liess M, Schulz R. Effects of the hormone mimetic insecticide tebufenozide on Chironomus riparius larvae in two different exposure setups. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2001; 49:171-178. [PMID: 11386731 DOI: 10.1006/eesa.2001.2055] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The effects of the molting-hormone agonistic insecticide tebufenozide on larvae of the midge Chironomus riparius Meigen were tested in two different exposure setups. After static contamination of first-instar larvae the NOEC, LOEC, and LC50 values were 13.2, 17.4, and 21.14 microg/L, respectively. Semistatic exposure of fourth-instar larvae revealed a lower susceptibility of elder larvae (NOEC 30 microg/L, LOEC 60 microg/L, and LC50 81.94 microg/L). In both cases mortality was not immediate; the effects were postponed and almost exclusively linked to the processes of pupation and emergence. Pupal mortality in the semistatic exposure scheme was twice as high in males as in females during a 100 microg/L treatment. This sex-specific effect probably resulted from the endocrine activity of tebufenozide. Its detection underlines the suitability of C. riparius as a model organism for investigating effects of endocrine-disrupting chemicals in aquatic insects.
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161
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Hahn T, Suen W, Kang S, Hsu S, Stidham H, Siedle A. An analysis of the Raman spectrum of syndiotactic polypropylene. 1. Conformational defects. POLYMER 2001. [DOI: 10.1016/s0032-3861(00)00904-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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162
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Husain M, Hahn T, Yedavalli VR, Ahmad N. Characterization of HIV type 1 tat sequences associated with perinatal transmission. AIDS Res Hum Retroviruses 2001; 17:765-73. [PMID: 11429117 DOI: 10.1089/088922201750237040] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) tat exon I sequences were analyzed from six mother-infant pairs after perinatal transmission. The tat open reading frame was maintained in 140 of the 154 clones analyzed, with a 90.9% frequency of intact tat open reading frames. In addition, a low degree of heterogeneity was observed in tat sequences within mothers, within infants, and between epidemiologically linked mother-infant pairs. However, the distances of tat sequences between epidemiologically unlinked individuals were greater than in epidemiologically linked mother-infant pairs. The infant sequences showed amino acid sequence patterns similar to those present in their respective mothers. The functional domains required for Tat function, including amino-terminal, cysteine-rich, core and basic regions, which constitute domains for activation and RNA binding, were highly conserved in most of the sequences. Phylogenetic analysis of 154 mother-infant tat sequences showed that they formed distinct clusters for each mother-infant pair and grouped with subtype B sequence. These findings suggest that an intact and functional tat gene is conserved in HIV-1 mother-infant isolates that are involved in perinatal transmission.
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163
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Joensen AM, Hahn T, Gelineck J, Overvad K, Ingemann-Hansen T. Articular cartilage lesions and anterior knee pain. Scand J Med Sci Sports 2001; 11:115-9. [PMID: 11252460 DOI: 10.1034/j.1600-0838.2001.011002115.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The present case-control study included as cases 24 athletes with anterior knee pain, and 17 controls, matching the cases according to gender and age. All cases had their most symptomatic knee examined by magnetic resonance imaging (MRI). Among controls one knee was chosen for examination at random. The MRI of the patella showed articular cartilage lesions in 17 out of 24 cases, whereas among the controls 4 out of 17 had articular cartilage lesions. (Odds Ratio 7.9 (95% confidence interval 1.9-33)). However, presence of articular cartilage lesions was not associated with duration of symptoms or intensity of the anterior knee pain. The present study showed a significant positive association between presence of articular cartilage lesions in the patella and presence of anterior knee pain, but further studies are needed to examine the relationship in detail.
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164
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Gladsjo JA, Rapaport MH, McKinney R, Auerbach M, Hahn T, Rabin A, Oliver T, Haze A, Judd LL. Absence of neuropsychologic deficits in patients receiving long-term treatment with alprazolam-XR for panic disorder. J Clin Psychopharmacol 2001; 21:131-8. [PMID: 11270908 DOI: 10.1097/00004714-200104000-00003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Studies to date on the effects of benzodiazepines on neuropsychologic function have yielded conflicting data with respect to the type, severity, and duration of deficits that may be induced by these agents. As part of a placebo-controlled trial of alprazolam-XR (extended release) administered in combination with cognitive-behavioral therapy in patients with panic disorder, a battery of tests was used to measure neuropsychologic function. Thirty-eight outpatients were randomly assigned to receive either alprazolam-XR or placebo. Dosages were titrated up so that the alprazolam group (N = 18) received a mean dose of 4 mg/day (reduced in two patients because of sedative side effects). Neuropsychologic function after 6 weeks of therapy at the target dosage was compared with baseline assessments in each group. Both groups showed a statistically significant improvement from baseline to repeated assessments on measures of attention, executive functioning, psychomotor speed, and visual memory (p < 0.001); these gains were attributed to a practice effect. No significant changes were noted in measures of learning, verbal memory, or reaction time, and neither group showed any deterioration from baseline to retesting in any aspect of neuropsychologic function. These findings call into question the assumption that long-term benzodiazepine therapy produces significant neuropsychologic deficit in patients with diagnosed anxiety disorders.
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165
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Jones R, Horowitz M, Wall D, Wingard J, Wolff S, McCarthy P, Hahn T. ASBMT policy statement regarding the methodology of evidence-based reviews in evaluating the role of blood and marrow transplantation in the treatment of selected diseases. American Society for Blood and Marrow Transplantation. Biol Blood Marrow Transplant 2001; 6:524-5. [PMID: 11063382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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166
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Simon M, Hahn T, Ford LA, Anderson B, Swinnich D, Baer MR, Bambach B, Bernstein SH, Bernstein ZP, Czuczman MS, Slack JL, Wetzler M, Herzig G, Schriber J, McCarthy PL. Retrospective multivariate analysis of hepatic veno-occlusive disease after blood or marrow transplantation: possible beneficial use of low molecular weight heparin. Bone Marrow Transplant 2001; 27:627-33. [PMID: 11319593 DOI: 10.1038/sj.bmt.1702854] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2000] [Accepted: 01/24/2001] [Indexed: 01/08/2023]
Abstract
This retrospective cohort study of 462 consecutive adult allogeneic and autologous blood or marrow transplantation (BMT) patients compared the incidence of hepatic veno-occlusive disease (VOD) after BMT with three prophylactic regimens. Patients receiving heparin (Hep), heparin + prostaglandin E1 (Hep + PGE1) or low molecular weight heparin (LMWH) as a prophylactic VOD regimen were compared to a historical cohort receiving no VOD prophylaxis. Of 462 BMT patients, VOD was diagnosed in 22% (31 of 142) of the no prophylaxis group, 11% (11 of 104) of the Hep, 12% (13 of 110) in the Hep + PGE1 and 4% (four of 106) of the LMWH group (P = 0.0002). VOD was the primary cause of death in 20% (12 of 59). By multivariate logistic regression, independent risk factors for developing VOD were: no VOD prophylactic regimen, unrelated allogeneic BMT, Karnofsky performance score (KPS) < 80 and aspartate aminotransferase (AST) > or =50 U/l. There was no increase in the rate of death due to hemorrhagic events or VOD in any prophylaxis group compared to the control group. Prospective randomized trials of Hep vs LMWH vs placebo are warranted to assess the efficacy of heparin compounds in the prevention of VOD.
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167
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Gradstein S, Hahn T, Barak Y, Malach L, Revel M, Bentwich Z, Handzel ZT. In vitro effects of recombinant TNF-alpha binding protein (rTBP-1) on hematopoiesis of HIV-infected patients. J Acquir Immune Defic Syndr 2001; 26:111-7. [PMID: 11242177 DOI: 10.1097/00042560-200102010-00002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Tumor necrosis factor-alpha (TNF-alpha) is believed to contribute to the hematopoietic failure often observed in patients with AIDS. Soluble TNF receptors (sTNFR) compete for TNF-alpha with cell surface receptors and thus may block its activity. The effect of the p55 sTNFR (recombinant TNF-binding protein-1 [rTBP-1]) on the clonogenic growth of hematopoietic progenitor cells from 27 HIV-infected patients was evaluated in comparison with 11 normal study subjects. Peripheral blood-derived, myelopoietic (i.e., granulomonocytic colony-forming cells [GM-CFC]) and erythropoietic (i.e, burst-forming unit, erythroid [BFU-E]) colonies were grown in 10-day semisolid cultures with increasing concentrations of rTBP-1. Significantly, dose-dependent increases occurred in GM-CFC from 17 of 21 AIDS patients and 12 of 21 in BFU-E at rTBP-1 concentrations of 1microg/ml to 25 microg/ml. In contrast, rTBP-1 failed to induce any appreciably increased colony formation in normal cell cultures. In 6 patients treated with highly active antiretroviral treatment (HAART), TBP-1 alone did not demonstrate the in vitro hematopoiesis-enhancing effect. This study may provide an initial step in development of therapeutic use of TBP as a TNF-alpha antagonist in HIV-infected patients who do not benefit sufficiently from antiretroviral treatment, and in other conditions in which increased levels of TNF-alpha may contribute to hematopoietic deficiencies.
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168
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Paik Y, Lee C, Cho M, Hahn T. Physical stability of the blue pigments formed from geniposide of gardenia fruits: effects of pH, temperature, and light. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2001; 49:430-2. [PMID: 11170609 DOI: 10.1021/jf000978f] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Fruits of Gardenia jasminoides contain geniposide which can be transformed to blue pigments by a simple modification. Colorless geniposide obtained from gardenia fruits by charcoal and silica gel column chromatographies was hydrolyzed with beta-glucosidase to yield genipin. The resulting genipin was transformed to blue pigments by reaction with amino acids (glycine, lysine, or phenylalanine). The stability of the blue pigments against heat, light, and pH was studied to examine the blue dye for possible use as a value-added food colorant. Thermal degradation reactions at temperatures of 60-90 degrees C were carried out at different pH levels within the range 5.0-9.0 (pH 5.0, acetate buffer; pH 7.0, phosphate buffer; and pH 9.0, CHES buffer). The blue pigments remained stable after 10 h at temperatures of 60-90 degrees C, and in some cases, more new pigments formed. The pigments were more stable at alkaline pH than neutral and acidic pH. Similarly, the pigments were stable under light irradiance of 5000-20 000 lux. In this case, pH effect was not significant.
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Mauschitz R, Cervar M, Hahn T, Pürstner P, Desoye G. Self-regulation of the endothelin receptor system in choriocarcinoma cells. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1502:224-34. [PMID: 11040447 DOI: 10.1016/s0925-4439(00)00049-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The human trophoblast secretes endothelin-1 (ET-1) and expresses ET receptors. The present study tested whether the transformed BeWo, JAR and JEG-3 choriocarcinoma cells: (1) secrete endothelin-1 (ET-1); (2) express both ET-A and ET-B receptor subtypes; and (3) have the potential to allow for autologous regulation of ET-receptor proteins. The cells were cultured for 24/48 h with or without 10% FCS and, in experiments on receptor regulation, with ET-1 (5-20 nM and 10 microM). ET-1 secretion was measured by RIA and receptor levels by immunoblotting. All cell types secreted ET-1 albeit at different levels and sensitivity to FCS. All cell lines expressed both ET-A (JEG-3>BeWo=JAR) and ET-B (JEG-3=JAR>BeWo) receptor subtypes, which could be up- and downregulated depending on ET-1 concentration, culture time and FCS presence. It is concluded that BeWo, JAR and JEG-3 choriocarcinoma cells secrete ET-1 and express both ET-A and ET-B receptor subtypes. The receptor levels can be regulated by ET-1. This provides the molecular basis for an autocrine system with the potential of autologous regulation of yet unidentified ET-1-induced functions.
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170
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Fausser JL, Rabarivola C, Meier B, Hahn T, Rumpler Y. Genetic comparison between different populations of Eulemur macaco flavifrons in northwest Madagascar using RAPD markers. Am J Primatol 2000; 51:249-55. [PMID: 10941441 DOI: 10.1002/1098-2345(200008)51:4<249::aid-ajp4>3.0.co;2-4] [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: 11/09/2022]
Abstract
Eulemur macaco flavifrons, the Sclater's black lemur, is a critically endangered subspecies of northwest Madagascar, which is not yet protected by any reserve. In order to study the feasibility of creating such a reserve, an area of outstanding biological importance was selected in the region of Maromandia-Sahamalaza, which is probably the only remaining place which would permit the long-term survival of the Sclater's black lemur. To determine if genetic management is needed for the Sahamalaza black lemur population, its genetic variability was estimated with random amplified polymorphic DNA (RAPD) markers and compared with other populations. These comparisons demonstrate that the Sahamalaza black lemurs have a genetic variability equivalent to those in other areas. Thus, we conclude that no genetic management is required at the present time.
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Cervar M, Huppertz B, Barth S, Hahn T, Weiss U, Kaufmann P, Desoye G. Endothelin A and B receptors change their expression levels during development of human placental villi. Placenta 2000; 21:536-46. [PMID: 10940204 DOI: 10.1053/plac.2000.0542] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Endothelin receptors have recently been found in non-vascular tissues including the human placenta. The present study investigated developmental changes in location and expression levels of endothelin A and B receptors (ETA-R, ETB-R) in human placentae and isolated trophoblast by comparing first and third trimester tissues. In the first trimester all cells and tissues were immunolabelled for ETA-R and ETB-R, whereas in third trimester placentae the syncytiotrophoblast (ETA-R, ETB-R) and macrophages (ETA-R) were unstained. Immunoblotting for both receptors revealed up to three bands at 33-35, 50 and 75 kDa, respectively, which were differentially present in the first and third trimester. Pre-adsorption of antibodies with oligopeptides used for antigen-generation weakened the immunoreactions. ETA-R protein levels decreased (P< 0.05) in total villous tissue and isolated trophoblast, whereas ETB-R was unchanged. ETB-R transcripts (RT-PCR) prevailed in both stages and tissues, but in contrast to the protein levels its preponderance decreased from first trimester to term in villous tissue (P< 0.01), because of a four to five-fold increase in ETA-R and only a two-fold (P< 0.05) increase in ETB-R mRNA levels (P< 0.01). We conclude that ET receptor location, intracellular processing and expression levels in human villous tissue change between the first and third trimester. This may reflect changing functions of ET-1 during placental development.
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MESH Headings
- Abortion, Legal
- Abortion, Therapeutic
- Adult
- Blotting, Western
- Chorionic Villi/embryology
- Chorionic Villi/metabolism
- Female
- Humans
- Immunoenzyme Techniques
- Molecular Sequence Data
- Pregnancy
- Pregnancy Trimester, First
- Pregnancy Trimester, Third
- RNA/analysis
- RNA, Messenger/metabolism
- Receptor, Endothelin A
- Receptor, Endothelin B
- Receptors, Endothelin/genetics
- Receptors, Endothelin/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Trophoblasts/metabolism
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172
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Hahn T, Hahn D, Blaschitz A, Korgun ET, Desoye G, Dohr G. Hyperglycaemia-induced subcellular redistribution of GLUT1 glucose transporters in cultured human term placental trophoblast cells. Diabetologia 2000; 43:173-80. [PMID: 10753038 DOI: 10.1007/s001250050026] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
AIMS/HYPOTHESIS We have recently shown that hyperglycaemia down-regulates the GLUT1 glucose transport system of term placental trophoblast. The reduction in GLUT1 protein alone was, however, not sufficient to explain the decrease in net glucose uptake, suggesting additional mechanisms. Therefore, we hypothesised that hyperglycaemia in vitro leads to a GLUT1 translocation from the trophoblast surface to intracellular sites. METHODS This was tested in our study by determining the subcellular distribution of GLUT1 in human term placental trophoblast (n = 5 placentas) cultured for 48 h with 5 compared with 25 mmol/l D-glucose in vitro using immunogold labelling. RESULTS Electron microscopic examination of cell profiles showed that 73% of total GLUT1 molecules reside in the trophoblast plasma membrane under basal conditions. The reduced GLUT1 expression (-20%; p < 0.05) after culture of the cells with 25 mmol/l glucose was accompanied by an internalisation of plasma membrane GLUT1, resulting in a loss of 40% (p < 0.05) in cell surface transporter labelling. Western blotting identified a characteristically broad band between 55-65 kDa, confirming the specificity of the GLUT1 antiserum. CONCLUSION/INTERPRETATION We postulate that in addition to down-regulating human GLUT1 protein concentrations, glucose exerts its autoregulatory effect on hexose transport in term placental trophoblast by altering GLUT1 partitioning between the plasma membrane and intracellular sites in favour of the latter.
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173
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Flack HD, Wondratschek H, Hahn T, Abrahams SC. Symmetry elements in space groups and point groups. Addenda to two IUCr reports on the nomenclature of symmetry. Acta Crystallogr A 2000; 56:96-8. [PMID: 10874422 DOI: 10.1107/s0108767399012283] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/1999] [Accepted: 09/23/1999] [Indexed: 11/10/2022] Open
Abstract
The definition of 'symmetry element' given in the Report of the IUCr Ad-Hoc Committee on the Nomenclature of Symmetry by de Wolff et al. [Acta Cryst. (1989). A45, 494-499] is shown to contain an ambiguity in the case of space groups P6/m, P6/mmm, P6/mcc and point groups 6/m and 6/mmm. The ambiguity is removed by redefining the 'geometric element' as a labelled geometric item in which the label is related to the rotation angle of the rotation or rotoinversion symmetry operation. The complete set of different types of glide plane is shown to contain three more than the 15 that are illustrated in the 1992 Report by de Wolff et al. [Acta Cryst. (1992). A48, 727-732].
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174
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Hahn T, Matala E, Chappey C, Ahmad N. Characterization of mother-infant HIV type 1 gag p17 sequences associated with perinatal transmission. AIDS Res Hum Retroviruses 1999; 15:875-88. [PMID: 10408724 DOI: 10.1089/088922299310584] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The gag p17 matrix sequences of human immunodeficiency virus type 1 (HIV-1) from seven infected mother-infant pairs were analyzed after perinatal transmission. The p17 matrix open reading frame was maintained in 143 of the 166 clones analyzed (86.2% frequency of intact p17 open reading frames). The functional domains essential for p17 matrix function in HIV-1 replication, including targeting of Gag to the plasma membrane, virus assembly and release, envelope glycoprotein incorporation into virus particle, virus entry, and localization of the virus preintegration complex to the nucleus of nondividing cells, were highly conserved in most of the sequences. In addition, examination of the three-dimensional structure of the p17 matrix protein in mother-infant isolates showed a high degree of conservation of amino acids required for correct folding and biological activity. Several amino acid motifs common to most of the mother-infant pairs sequences, including pair-specific signature sequences, were observed. There was a low degree of heterogeneity of gag p17 sequences within mothers, within infants, and between mother-infant pairs, but the distances were greater between epidemiologically unlinked individuals. Phylogenetic analyses of 166 mother-infant pairs and 181 other p17 sequences available from HIV-1 databases revealed distinct clusters for each mother-infant pair and for other p17 sequences. In conclusion, these findings indicate that an intact and functional gag p17 matrix is maintained during maternal-fetal transmission and that several motifs in p17 may be associated with perinatal transmission.
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175
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Tasman A, Hahn T, Maiste A. Menstrual cycle synchronized changes in brain stem auditory evoked potentials and visual evoked potentials. Biol Psychiatry 1999; 45:1516-9. [PMID: 10356636 DOI: 10.1016/s0006-3223(98)00196-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Several studies have reported changes in the spontaneous electroencephalogram of women across the menstrual cycle (MC), raising questions on whether sensory or cognitive evoked potentials would change with MC as well. Some of these studies have found changes synchronized with MC in visual event-related brain potentials (ERPs) and brain stem auditory evoked potentials (BAEPs), whereas others have reported none. METHODS In the present study, we attempted to study the changes in P300 component of visual ERPs, and in BAEPs across the MC in healthy women. RESULTS The latency of P300 was longer during the ovulatory phase. Decrease across the MC phases was found for the amplitude of BAEP waves I and III, and for the wave V latency and the III-V interpeak latency. CONCLUSIONS The results indicate that there may be a small relationship between visual ERP or BAEP and MC phase.
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