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Haisraely O, Lawrence Y, Weiss I, Kaidar-Pearson O, Jaffe M, Appel S, Symon Z. Fraction Size, Total Dose and Respiratory Control Impact Local Control in Adrenal SBRT. Int J Radiat Oncol Biol Phys 2023; 117:S66. [PMID: 37784548 DOI: 10.1016/j.ijrobp.2023.06.369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Stereotactic body radiotherapy (SBRT) is an effective treatment for oligometastatic disease in multiple sites, however, the optimal radiation dose for long term local control of adrenal metastases has not yet been determined. The aim of this study is to evaluate outcomes of adrenal SBRT and to evaluate factors that correlate with local control MATERIALS/METHODS: After IRB approval, a retrospective data review of patients treated with SBRT on adrenal metastases was conducted, at a medical center in Israel between 2015 and 2021. Biologic Equivalent Dose (BED) were calculated using an alpha beta ration of 10. Kaplan Meier and Cox regression were calculated to describe the hazard ratio for local control and survival using statistical software. RESULTS Fifty-eight cases of adrenal SBRT were identified. The average age was 67 years (ranging 42-92). Forty-three percent of primary tumor was non-small cell lung cancer. The lesions were equally distributed between the right and left adrenal gland. Six patients had bilateral radiation treatment. Fifty-eight percent of the cases were in the setting of oligometastatic disease (less than 5 lesions) with the rest having progression in the adrenal. PET-CT scans were available for follow up in 55% of patients and CT in the rest. The average GTV volume was 42 cm2 respiratory control through 4D and breath hold was performed in 86% of cases. The median follow up time, for local control, was 10 months with a range of 1-54 mos. Univariate analysis local control, during the last follow up, was seen in 74% of cases. Total dosage was equal to or above 72 Gy and dosage per fraction was equal to or above 8 Gy. The use of respiratory motion was found significant for local control. Only a fraction size equal to or above 8 Gy and a total dosage equal to and above 72 Gy were found significant for local failure (HR = 0.26, p = 0.024 and HR = 0.28, p = 0.019). With multivariable analysis the dosage per fraction ≥8 Gy continued to be significant after adjusting for total dose, histology, side, and motion management. Two patients had clinical signs of adrenal insufficiency and both received bilateral adrenal radiation. Bowel toxicity was low: 1 patient had >G3 toxicity. CONCLUSION In the largest single institution series reported to date, we found unilateral adrenal SBRT to be safe, however, bilateral treatment harbors a risk of adrenal insufficiency. Dose per fraction ≥8 Gy was the most powerful predictor of local control, and a total dose ≥72gy and motion management were also significant. In conclusion, we propose a treatment regimen with a fraction size of at least 8 Gy and a total dosage of at least 72 Gy for evaluation, in a prospective clinical trial.
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Affiliation(s)
- O Haisraely
- Chaim Sheba Medical Center, Ramat Gan, Israel
| | - Y Lawrence
- Radiation Oncology, Sheba Medical Center, Ramat Gan, Israel
| | - I Weiss
- Radiation Oncology Department, Sheba Medical Center, Ramat Gan, Israel
| | | | - M Jaffe
- UNIC Medical School, Haogen, Israel
| | - S Appel
- Radiation Oncology, Sheba Medical Center, Ramat Gan, Israel
| | - Z Symon
- Radiation Oncology Department, Sheba Medical Center, Ramat Gan, Israel
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Brochhausen C, Froschermeier F, Alt V, Pfeifer C, Mayr A, Weiss I, Babel M, Siegmund H, Kerschbaum M. New quantitative automated model to simulate bacterial dissemination in human tissue during irrigation of contaminated wounds. Eur Cell Mater 2021; 42:63-71. [PMID: 34342876 DOI: 10.22203/ecm.v042a05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
This study presents a simple and cost-effective model using microparticles to simulate the bacterial distribution pattern in soft tissue after low- and high-pressure irrigation. Silica coated iron microparticles [comparable diameter (1 µm) and weight (0.8333 pg) to Staphylococcus aureus] were applied to the surface of twenty fresh human muscle tissue samples in two amputated lower legs. Particle dissemination into deep tissue layers as an undesired side effect was investigated in four measuring fields as positive control (PC) as well as after performing pulsatile high-pressure (HP, 8 measuring fields) and low-pressure flushing (LP, 8 measuring fields). Five biopsies were taken out of each measuring field to get a total number of 100 biopsies. After histological and digital image processing, the specimens were analysed, and all incomplete sections were excluded. A special detection algorithm was parameterised using the open source bioimage analysis software QuPath. The application of this detection algorithm enabled automated counting and detection of the particles with a sensitivity of 95 % compared to manual counts. Statistical analysis revealed significant differences (p < 0.05) in our three different sample groups: HP (M = 1608, S = 302), LP (M = 2176, SD = 609) and PC (M = 4011, SD = 686). While both HP and LP flushing techniques are able to reduce the number of bacteria, a higher effectiveness is shown for HP irrigation. Nevertheless, a challenge for the validity of the study is the use of dead tissue and therefore a possible negative influence of high-pressure irrigation on tissue healing and further dispersion of particles cannot be evaluated.
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Affiliation(s)
| | | | | | | | | | | | | | | | - M Kerschbaum
- Department of Trauma Surgery, University Medical Centre Regensburg, Franz-Josef-Strauss Allee 11, 93053 Regensburg,
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Lewin R, Bar-Orian I, Honig N, Tsvang L, Ben-Ayun M, Weiss I, Symon Z. PO-1343 Dose-escalated stereotactic radiotherapy for prostate cancer: A feasibility study using a rectal spacer and urethral sparing. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)07794-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Haisraely O, Weiss I, Lawrence Y, Lewin R, Symon Z. Urinary Continence and Sexual Potency Following Surgery and Adjuvant/Salvage Radiotherapy Versus Primary Radiotherapy: Is There A Winner? Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Lewin R, Laufer M, Berger R, Tsvang L, ben-Ayun M, Weiss I, Symon Z. Re-Irradiation with Extreme Hypo-Fractionation to the Prostate for Local Recurrence after Primary Radiotherapy. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Jacobson G, Lawrence Y, Appel S, Weiss I, Galper S, Ben-David M, Weizman N, Goldstein J, Peled N, Symon Z. Benefits of Continuous Positive Airway Pressure (CPAP) in Radiotherapy: A Prospective Trial. Int J Radiat Oncol Biol Phys 2019. [DOI: 10.1016/j.ijrobp.2019.06.432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Sadetskii I, Eshet Y, Tsvang L, Amit U, Weiss I, Benayun M, Lawrence Y, Symon Z. Response assessment using 68 Gallium (68Ga) Prostate-Specific Membrane Antigen (PSMA) Positron Emission Tomography - Computed Tomography (PT/CT) inpatients with oligometastatic prostate cancer undergoing Stereotactic Body Radiotherapy (SBRT). Int J Radiat Oncol Biol Phys 2019. [DOI: 10.1016/j.ijrobp.2019.06.1240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Hammer L, Laufer M, Dotan Z, Leibowitz-Amit R, Berger R, Felder S, Weiss I, Lawrence Y, Symon Z. Accelerated Hypo-Fractionated Radiation Therapy for Elderly Frail Bladder Cancer Patients Unfit for Surgery or Chemotherapy. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Hammer L, Hausner D, Morag O, ben-Ayun M, Alezra D, Dubinski S, Tsvang L, Jacobson G, Amit U, Katzman T, Gnessin H, Shefer K, Weiss I, Yanovsky I, Golan T, Symon Z, Lawrence Y. Celiac Plexus Radiosurgery, a New Modality for Cancer Pain Management – Final Results of a Phase II Clinical Trial. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.06.074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Katzman T, Symon Z, Weiss I, Lawrence Y. PV-0363: The effect of the use of CPAP on set-up errors in SBRT treatments in the thorax. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)30673-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Bodin T, García-Trabanino R, Weiss I, Jarquín E, Glaser J, Jakobsson K, Lucas RAI, Wesseling C, Hogstedt C, Wegman DH. Intervention to reduce heat stress and improve efficiency among sugarcane workers in El Salvador: Phase 1. Occup Environ Med 2016; 73:409-16. [PMID: 27073211 PMCID: PMC4893112 DOI: 10.1136/oemed-2016-103555] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 03/24/2016] [Indexed: 11/04/2022]
Abstract
BACKGROUND Chronic heat stress and dehydration from strenuous work in hot environments is considered an essential component of the epidemic of chronic kidney disease in Central America. OBJECTIVE (1) To assess feasibility of providing an intervention modelled on OSHA's Water.Rest.Shade programme (WRS) during sugarcane cutting and (2) to prevent heat stress and dehydration without decreasing productivity. METHODS Midway through the 6-month harvest, the intervention introduced WRS practices. A 60-person cutting group was provided water supplied in individual backpacks, mobile shaded rest areas and scheduled rest periods. Ergonomically improved machetes and efficiency strategies were also implemented. Health data (anthropometric, blood, urine, questionnaires) were collected preharvest, preintervention, mid-intervention and at the end of harvest. A subsample participated in focus group discussions. Daily wet bulb globe temperatures (WBGT) were recorded. The employer provided individual production records. RESULTS Over the harvest WBGT was >26°C from 9:00 onwards reaching average maximum of 29.3±1.7°C, around 13:00. Postintervention self-reported water consumption increased 25%. Symptoms associated with heat stress and with dehydration decreased. Individual daily production increased from 5.1 to a high of 7.3 tons/person/day postintervention. This increase was greater than in other cutting groups at the company. Focus groups reported a positive perception of components of the WRS, and the new machete and cutting programmes. CONCLUSIONS A WRS intervention is feasible in sugarcane fields, and appears to markedly reduce the impact of the heat stress conditions for the workforce. With proper attention to work practices, production can be maintained with less impact on worker health.
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Affiliation(s)
- T Bodin
- Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden
| | - R García-Trabanino
- Association of Nephrology and Hypertension of El Salvador, San Salvador, El Salvador
| | - I Weiss
- La Isla Foundation, Ada, Michigan, USA
| | - E Jarquín
- Agency for Development and Agricultural Health (AGDYSA), San Salvador, El Salvador
| | - J Glaser
- La Isla Foundation, Ada, Michigan, USA
| | - K Jakobsson
- Department of Public Health and Community Medicine, Gothenburg University, Gothenburg, Sweden
| | - R A I Lucas
- School of Sport, Exercise & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - C Wesseling
- Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden
| | - C Hogstedt
- Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden
| | - D H Wegman
- Department of Work Environment, University of Massachusetts Lowell, Lowell, Massachusetts, USA
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Saad A, Goldstein J, Lawrence Y, Urban D, Leibowitz R, Berger R, Spieler B, Weiss I, Symon Z. Are the 2015 Modifications to the National Comprehensive Cancer Network Guidelines for High-Risk and Very High-Risk Prostate Cancer Useful to Radiation Oncologists? Int J Radiat Oncol Biol Phys 2015. [DOI: 10.1016/j.ijrobp.2015.07.1134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Saad A, Goldstein J, Lawrence R, Spieler B, Tsang L, Alezra D, Weiss I, Leibovitch R, Berger R, Symon Z. PO-0741: Outcomes of conformal RT and ADT in high risk prostate cancer: is there a role for surgery? Radiother Oncol 2015. [DOI: 10.1016/s0167-8140(15)40733-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Symon Z, Saad A, Even- Sapir E, Ben-Haim S, Davidson T, Weiss I, Berger R, Sarit A, Goldstein J. Does Choline PET/CT Change the Management of Prostate Cancer Patients With Biochemical Failure? Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.1405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Symon Z, Tsvang L, Dubinski S, Weiss I, Pfeffer M, Lawrence Y. Volumetric Modulated Arc Therapy With a Gentle Hypofractionated Concomitant Integrated Prostate Boost: Toxicity and Quality of Life Outcomes. Int J Radiat Oncol Biol Phys 2012. [DOI: 10.1016/j.ijrobp.2012.07.474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Vierling KT, Bässler C, Brandl R, Vierling LA, Weiss I, Müller J. Spinning a laser web: predicting spider distributions using LiDAR. Ecol Appl 2011; 21:577-588. [PMID: 21563587 DOI: 10.1890/09-2155.1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
LiDAR remote sensing has been used to examine relationships between vertebrate diversity and environmental characteristics, but its application to invertebrates has been limited. Our objectives were to determine whether LiDAR-derived variables could be used to accurately describe single-species distributions and community characteristics of spiders in remote forested and mountainous terrain. We collected over 5300 spiders across multiple transects in the Bavarian National Park (Germany) using pitfall traps. We examined spider community characteristics (species richness, the Shannon index, the Simpson index, community composition, mean body size, and abundance) and single-species distribution and abundance with LiDAR variables and ground-based measurements. We used the R2 and partial R2 provided by variance partitioning to evaluate the predictive power of LiDAR-derived variables compared to ground measurements for each of the community characteristics. The total adjusted R2 for species richness, the Shannon index, community species composition, and body size had a range of 25-57%. LiDAR variables and ground measurements both contributed >80% to the total predictive power. For species composition, the explained variance was approximately 32%, which was significantly greater than expected by chance. The predictive power of LiDAR-derived variables was comparable or superior to that of the ground-based variables for examinations of single-species distributions, and it explained up to 55% of the variance. The predictability of species distributions was higher for species that had strong associations with shade in open-forest habitats, and this niche position has been well documented across the European continent for spider species. The similar statistical performance between LiDAR and ground-based measures at our field sites indicated that deriving spider community and species distribution information using LiDAR data can provide not only high predictive power at relatively low cost, but may also allow unprecedented mapping of community- and species-level spider information at scales ranging from stands to landscapes. Therefore, LiDAR is a viable tool to assist species-specific conservation as well as broader biodiversity planning efforts not only for a growing list of vertebrates, but for invertebrates as well.
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Affiliation(s)
- K T Vierling
- Department of Fish and Wildlife Resources, University of Idaho, Box 441136, Moscow, Idaho 83844-1136, USA.
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Grigoryan O, Weiss I, Feldon J. Social isolation improves working memory at reversal but not primary radial-arm maze learning in rats. Zh Vyssh Nerv Deiat Im I P Pavlova 2010; 60:560-567. [PMID: 21254724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Social isolation starting from the 21st day of birth affected neither a short-term nor a long-term memory in male rats at primary acquisition learning in an 8-arm radial maze. A number of the short-term and long-term memory errors were substantially decreased during primary learning but the difference between groups was not significant. Isolates were faster to start a search in an individual trial and took less time to finish offa trial. During the reversal learning, when baited and non-baited arms were reversed, the isolates outperformed of socially reared rats on working but not reference memory task. In overall they made twice less working memory errors than socially reared animals. During the reversal learning the isolates were also faster than non-isolates in initiation and completion of a trial. Maternal separation of rat's pups on the postnatal days 1-21 for 4 hr per day did not affect either working or reference memory on both primary and reversal learning. The data obtained are discussed on basis of influence of stress in early postnatal life on hypothalamo-pituitary axis and its effects on behavior of adult animals.
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Affiliation(s)
- O Grigoryan
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow.
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Wald O, Amir G, Avniel S, Bar-Shavit Y, Weiss I, Peled A, Izhar U. P-130 The chemokine CXCL12 is involved in shaping the immune cellpopulation infiltrating NSCLC. Lung Cancer 2005. [DOI: 10.1016/s0169-5002(05)80624-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Yang Ran, Qinfen Zheng, Weiss I, Davis L, Abd-Almageed W, Liang Zhao. Pedestrian classification from moving platforms using cyclic motion pattern. IEEE International Conference on Image Processing 2005 2005. [DOI: 10.1109/icip.2005.1530190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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Abstract
Receptors for plasminogen activators present on endothelial cell (EC) surface regulate local plasmin activity. Plasmin generation by human ECs, derived from cerebral cortex, skin and lung, iliac artery, iliac vein, aorta and coronary artery, was studied. The respective ECs were treated with recombinant tissue plasminogen activator (rt-PA) or with recombinant urokinase-type plasminogen activator (ru-PA), washed, plasminogen added and the plasmin generated then assayed. The largest amounts of plasmin were generated by cerebral ECs, under baseline conditions or after exposure to rt-PA or ru-PA (P < 0.0001). Exposure to rt-PA also resulted in more plasmin generation than ru-PA in the cerebral ECs (P < 0.0001) but not in the other ECs. Heparin enhanced plasmin generation by both rt-PA and ru-PA. Specific antibody against annexin II, a t-PA receptor, blocked plasmin generation by rt-PA. Western blotting showed higher amounts of annexin II on the cell membrane in cerebral ECs. This suggests that expression of annexin II in ECs depends on their location, being greatest in cerebral ECs. In contrast, expression of u-PA receptor was the same for all ECs. This has implications for higher risk of intracranial bleeding during thrombolytic therapy, and for a role of t-PA in neurological development and function.
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Affiliation(s)
- H C Kwaan
- Division of Hematology and Oncology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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Abstract
Apoptosis is involved in many biological processes, especially during chemotherapy in cancer patients. Chemotherapy is also associated with an increased risk of thrombosis. The relationship between thrombogenicity and apoptosis was studied in various human tumour cell lines and non-tumour cell lines. Apoptosis was induced by the chemotherapeutic agent camptothecin and by Fas ligand, then quantified by staining with fluorescein isothiocyanate-conjugated annexin V and propidium iodide. A significant correlation between thrombin generation and degree of apoptosis was observed (P < 0.0005). Addition of anti-tissue factor antibody in excess or of tissue factor pathway inhibitor partially inhibited thrombin generation, suggesting that tissue factor activation was responsible for this process. A statistical correlation between tissue factor activity and degree of apoptosis was also found (P < 0.005). Both thrombin generation and tissue factor activity were blocked by the addition of annexin V, which binds and inhibits phosphatidylserine. This indicates that the exteriorization and exposure of phosphatidylserine on the cell surface membrane during apoptosis were essential for both thrombin generation and tissue factor activation.
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Affiliation(s)
- J Wang
- Division of Hematology/Oncology, Department of Medicine, Northwestern University Medical School, Chicago, IL, USA
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Schneider U, Altmann A, Baumann M, Bernzen J, Bertz B, Bimber U, Broese T, Broocks A, Burtscheidt W, Cimander KF, Degkwitz P, Driessen M, Ehrenreich H, Fischbach E, Folkerts H, Frank H, Gurth D, Havemann-Reinecke U, Heber W, Heuer J, Hingsammer A, Jacobs S, Krampe H, Lange W, Lay T, Leimbach M, Lemke MR, Leweke M, Mangholz A, Massing W, Meyenberg R, Porzig J, Quattert T, Redner C, Ritzel G, Rollnik JD, Sauvageoll R, Schläfke D, Schmid G, Schröder H, Schwichtenberg U, Schwoon D, Seifert J, Sickelmann I, Sieveking CF, Spiess C, Stiegemann HH, Stracke R, Straetgen HD, Subkowski P, Thomasius R, Tretzel H, Verner LJ, Vitens J, Wagner T, Weirich S, Weiss I, Wendorff T, Wetterling T, Wiese B, Wittfoot J. Comorbid anxiety and affective disorder in alcohol-dependent patients seeking treatment: the first Multicentre Study in Germany. Alcohol Alcohol 2001; 36:219-23. [PMID: 11373258 DOI: 10.1093/alcalc/36.3.219] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The goals of this study were to describe demographic variables, drinking history, and the 6-month prevalence of Axis I comorbidity among alcohol-dependent subjects in GERMANY: The variables: amount of alcohol consumption, age at onset of the first alcohol consumed, age at onset of daily alcohol consumption, age at onset of withdrawal symptoms and number of detoxifications were related to the different comorbid disorders and gender. In this study, 556 patients from 25 alcohol treatment centres were enrolled between 1 January 1999 and 30 April 1999. After a minimum of 10 days of sobriety patients who fulfilled ICD-10 and DSM-IV criteria of alcohol dependence were interviewed for data collection using the Mini-DIPS (German version of the Anxiety Disorders Interview Schedule) and a standardized psychosocial interview. The 6-month prevalence of comorbid Axis I disorders was 53.1%. Among the patients with comorbidity, affective and anxiety disorders were most frequent. Comorbid stress disorder was associated with an early start of drinking, an early beginning of withdrawal symptoms, highest number of detoxifications, and the highest amount of alcohol consumed. Female patients with anxiety disorder consumed more alcohol and started earlier than females without this comorbid disorder. The data do not answer the question of the pathogenesis of comorbid disorders and alcoholism, but indicate that stress disorders in alcoholic patients and anxiety disorders in female alcoholics influence the course and severity of alcoholism.
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Affiliation(s)
- U Schneider
- Medizinische Hochschule Hannover. Georg-August Universität, Göttingen, Germany
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Abstract
OBJECTIVE To review a large population of children receiving mechanical ventilation to establish a baseline rate of extubation success and failure and to identify those characteristics that place a patient at greater risk of failing planned extubation. DESIGN Retrospective chart review. SETTING University-affiliated children's hospital with a 20-bed pediatric ICU. PATIENTS All 632 patients receiving mechanical ventilation during the 2-year period from July 1, 1996, to June 30, 1998. METHOD Patients receiving mechanical ventilation were identified via a computerized database. Charts were reviewed of all patients who were reintubated within 72 h of extubation. MEASUREMENTS AND RESULTS There were 548 planned extubation events, of which 521 were successful. Twenty-seven patients failed planned extubation at least once; only the first attempt at extubation was included in the analysis. The failure rate of planned extubations was 4.9%. Including only patients who had received mechanical ventilation for > 24 h before extubation, the failure rate was 6.0%. For patients intubated > 48 h, the failure rate was 7.9%. The patients who failed extubation were found to be significantly younger and to have received mechanical ventilation longer than those who succeeded, in both the analysis of all patients receiving mechanical ventilation and the subgroup of those receiving mechanical ventilation > 24 h. When only patients who had received mechanical ventilation for > 48 h were analyzed, the difference in age was no longer significant, but the duration of ventilation before extubation was still significantly longer for those who failed. CONCLUSION We determined the overall failure rate of planned extubations in a large population of pediatric patients to be 4.9%. Those patients who were younger and had received mechanical ventilation longer were more at risk for extubation failure.
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Affiliation(s)
- S Edmunds
- Division of Pediatric Critical Care, Mattel Children's Hospital, UCLA Medical Center, Los Angeles, CA 90024-1783, USA
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Paule S, Weiss I, Urbaszek A, Schaldach M. ENTWURF UND IMPLEMENTIERUNG EINES TOPOLOGISCHEN MODELLS DER KARDIALEN ERREGUNGSLEITUNG ZUR SIMULATION UND ANALYSE VON HERZRHYTHMUSSTÖRUNGEN. BIOMED ENG-BIOMED TE 2000. [DOI: 10.1515/bmte.2000.45.s1.365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Weiss I, Paule S, Urbaszek A, Schaldach M. IDENTIFIKATION ARRHYTHMOGENER SUBSTRATZUSTÄNDE UND REGLERENTWURF ZUR OPTIMIERUNG DER ANTITACHYKARDEN ELEKTROSTIMULATION. BIOMED ENG-BIOMED TE 2000. [DOI: 10.1515/bmte.2000.45.s1.371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Weiss I, Paule S, Urbaszek A, Schaldach M. MODELLBASIERTE ANALYSE DER THERAPEUTISCHEN WIRKUNGSMECHANISMEN VON UNTERSCHWELLIGER MYOKARDSTIMULATION. BIOMED ENG-BIOMED TE 2000. [DOI: 10.1515/bmte.2000.45.s1.373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Paule S, Weiss I, Urbaszek A, Schaldach M. [Atrial fibrillation--study of electrophysiologic influences on optimizing cardiac stimulation methods]. BIOMED ENG-BIOMED TE 1998; 43 Suppl:356-7. [PMID: 9859396 DOI: 10.1515/bmte.1998.43.s1.356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- S Paule
- Zentralinstitut für Biomedizinische Technik, Universität Erlangen-Nürnberg
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Weiss I, Paule S, Urbaszek A, Schaldach M. [Early detection of cardiac arrhythmias by computer-assisted online analysis of monophasic action potentials]. BIOMED ENG-BIOMED TE 1998; 43 Suppl:90-1. [PMID: 9859272 DOI: 10.1515/bmte.1998.43.s1.90] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- I Weiss
- Zentralinstitut für Biomedizinische Technik, Universität Erlangen-Nürnberg
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Galani R, Weiss I, Cassel JC, Kelche C. Spatial memory, habituation, and reactions to spatial and nonspatial changes in rats with selective lesions of the hippocampus, the entorhinal cortex or the subiculum. Behav Brain Res 1998; 96:1-12. [PMID: 9821539 DOI: 10.1016/s0166-4328(97)00197-6] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Various spatial memory deficits have been described in rats with damage to the hippocampal formation (including the subiculum and the entorhinal cortex) and particularly in rats with selective lesions of the hippocampus proper. So far, the involvement of the entorhinal cortex in spatial memory is still controversial and the role of the subiculum is poorly documented. The aim of the present study was to compare the behavioural effects of selective lesions of the hippocampus, the entorhinal cortex or the subiculum in (a) a water-maze task using testing procedures sensitive to the disruption of reference or working memory and (b) in an object exploration task designed to evaluate habituation and subsequently reactions to changes of the spatial layout of objects (spatial change) or to the substitution of a familiar object by a new one (nonspatial change). Our results showed several similarities between the behavioural consequences of damage to each of the three structures. A few differences were also noted. Hippocampal rats were impaired in all spatial tasks, but they reacted like controls to a nonspatial change. The rats sustaining lesions of the entorhinal cortex or the subiculum were not impaired in the reference-memory procedure of the water-maze task and showed a deficit in reacting to a nonspatial change. Overall, our results confirm the central role of the hippocampus in spatial memory and also suggest a role for the entorhinal cortex and the subiculum in processing spatial informations. In addition, they indicate that the entorhinal cortex and the subiculum may have a hippocampal-independent role in memory.
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Affiliation(s)
- R Galani
- Laboratoire de Neurosciences Comportementales et Cognitives, LN2C, UMR 7521 du CNRS/Université Louis Pasteur, Strasbourg, France.
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Portel L, Tunon de Lara JM, Vernejoux JM, Weiss I, Taytard A. [Osmolarity of solutions used in nebulization]. Rev Mal Respir 1998; 15:191-5. [PMID: 9608990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Inhaled medications are widely used in patients suffering from bronchial diseases. Beside their pharmacological properties, nebulised solutions have physico-chemical characteristics that can alter bronchial reactivity. Non-isotonic solutions can induce a bronchial hyperresponsiveness and/or a severe bronchonconstriction. Nevertheless, multiple drugs are used for nebulisation despite their unknown osmolarity. The aim of this study was to measure the tonicity of drug solutions commonly used for nebulisation in patients suffering from bronchial disease. Drug solutions were prepared either according to manufacturer recommendations or by diluting the stock in 5 ml of NaCl (0.9%) or H2CO3 (0.14%). Although bronchodilatator solutions (i.e. salbutamol, terbulatine, ipratropium bromide) were nearly isotonic, some drugs prepared for nebulisation had either a very high (e.g. mesna, netilmicine) or a very low (e.g. gomenol, sodium cromoglycate) tonicity. These values may be responsible for bronchoconstriction. Some hypertonic solutions, prepared with drugs such as acetylcytein or netilmycin, are not commercialised for nebulisation but are commonly used for aerosol therapy. In addition, solutions initially isotonic could become significantly hypertonic towards the end of nebulisation. Taken together, these results suggest that non-isotonic solutions should be used with caution specially in patients with bronchial hyperresponsiveness, even when aerosol therapy is prescribed for upper airways.
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Affiliation(s)
- L Portel
- CHU de Bordeaux, Hôpital du Haut-Lévêque, Pessac
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Schmidt M, Weiss I, Urbaszek A, Steffen P, Schaldach M. [Methods of pattern recognition for detection of neurohumoral information in monophasic action potentials]. BIOMED ENG-BIOMED TE 1998; 42 Suppl:133-4. [PMID: 9517082 DOI: 10.1515/bmte.1997.42.s2.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- M Schmidt
- Zentralinstitut für Biomedizinische Technik, Universität Erlangen-Nürnberg
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Weiss I, Urbaszek A, Schaldach M. [Stimulation early after-depolarization-induced reentry mechanisms for developing anti-tachycardic therapy algorithms]. BIOMED ENG-BIOMED TE 1998; 42 Suppl:275-6. [PMID: 9517149 DOI: 10.1515/bmte.1997.42.s2.275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- I Weiss
- Zentralinstitut für Biomedizinische Technik, Universität Erlangen-Nürnberg
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Paule S, Weiss I, Bär W, Urbaszek A, Schaldach M. [Modeling myocardial Ca regulation mechanisms for the development of anti-tachycardic stimulation methods]. BIOMED ENG-BIOMED TE 1998; 42 Suppl:139-40. [PMID: 9517085 DOI: 10.1515/bmte.1997.42.s2.139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- S Paule
- Zentralinstitut für Biomedizinische Technik, Universität Erlangen-Nürnberg
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Weiss I, Urbaszek A, Schaldach M. [Model based study of myocardial stimulation mechanisms]. BIOMED ENG-BIOMED TE 1997; 42:16-23. [PMID: 9172726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The present study investigated the mechanisms of electrical stimulation of a myocardial fibre with the aim of developing improved minimally invasive stimulation methods. Using a dynamic myocyte model, the ionic currents crossing the voltage-dependent channels of the membrane are computed. To trigger an action potential, the membrane must first be depolarized to the threshold potential, when further depolarization continues spontaneously through the avalanche-like opening of the sodium channels. For the development of an action potential, not merely the amount of charge injected into the cell during the stimulus is of importance, but an above-threshold magnitude of the stimulation current is also required. The smallest energy required is achieved when the stimulus duration is chosen to be equal to the chronaxie. A second aspect of the study concerned the far-field stimulation of a muscle fibre, achieved by generating a potential gradient along the fibre. First, using a continuous fibre model, the fibre activating function is computed. In a more detailed study, the discrete segmental structure of the fibre determined by the gap junctions is taken into account, and the impact of these junctions on the activating function analysed. By optimizing the electrode configuration, an appropriate activating function results which guarantees successful stimulation when its maximum is above than threshold potential. The most important finding is that the myocardium can be stimulated by floating electrodes, thus opening up new possibilities for a less invasive electro-stimulation of the heart.
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Affiliation(s)
- I Weiss
- Zentralinstitut für Biomedizinische Technik, Friedrich-Alexander-Universität Erlangen, Nürnberg
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Weiss I, Urbaszek A, Schaldach M. Modellbasierte Untersuchung myokardialer Stimulationsmechanismen - Investigation of Cardiac Stimulation Mechanisms Using a Model. BIOMED ENG-BIOMED TE 1997. [DOI: 10.1515/bmte.1997.42.1-2.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Weiss I, Gorodnitzky Z, Korenman Z, Yagupsky P. Serotyping and susceptibility to macrolides and other antimicrobial drugs of Streptococcus pyogenes isolated from patients with invasive diseases in southern Israel. Eur J Clin Microbiol Infect Dis 1997; 16:20-3. [PMID: 9063669 DOI: 10.1007/bf01575115] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Fifty-seven strains of Streptococcus pyogenes isolated from septic patients and 52 isolates from nonbacteremic patients in southern Israel were investigated for their susceptibility to new macrolides and other antimicrobial drugs. In addition, typing of the isolates by M protein and T antigen was performed. All organisms were susceptible to penicillin and chloramphenicol, 59% to tetracycline, and 7% to trimethoprim-sulfamethoxazole. All isolates but one (99%) were susceptible to clarithromycin, azithromycin, erythromycin, and clindamycin. The MIC90 of clarithromycin, erythromycin, and clindamycin was 0.064, 0.125, and 0.094 microgram/ml, respectively. Overall, 96% of the isolates could be typed by T antigen, but only 43% were M-protein typeable. No predominance of any particular M-protein type was observed. No significant differences between blood isolates and organisms derived from other sources were observed in the antibiotic susceptibility patterns or the distribution of serotypes. It is concluded that invasive Streptococcus pyogenes infections in southern Israel are caused by multiple unrelated strains. The organism remains susceptible to macrolides and clindamycin.
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Affiliation(s)
- I Weiss
- Clinical Microbiology Laboratories, Soroka Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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Relys V, Weiss I. Micrargus alpinus sp. n., eine weitere Art der M. herbigradus-Gruppe aus Österreich (Arachnida: Araneae: Linyphiidae). REV SUISSE ZOOL 1997. [DOI: 10.5962/bhl.part.80007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Weiss I, Urbaszek A, Ostermeier M, Schaldach M. Modellstudie zur Elektrostimulation der Herzmuskelfaser. BIOMED ENG-BIOMED TE 1996. [DOI: 10.1515/bmte.1996.41.s1.72] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Abstract
OBJECTIVE To examine the pulmonary and cardiac function of children who survived an episode of acute hypoxemic respiratory failure. DESIGN Descriptive cohort analysis. SETTING Pediatric clinical research center of a university hospital. PATIENTS Utilizing the criteria of PaO2 < 75 torr (< 10 kPa) with an FIO2 of > 0.5 while intubated, bilateral diffuse pulmonary infiltrates on chest radiograph, and exclusion of cardiogenic pulmonary edema, 147 patients were identified during the 6-yr period from July 1, 1986 to August 1, 1993. Fifty patients survived to discharge and 37 were alive at the time of follow-up. Fourteen patients were eventually entered into the study. INTERVENTIONS The study patients were given a test battery consisting of a questionnaire specific for cardiopulmonary status, a physical examination, a chest radiograph, electrocardiography, echocardiography with detailed examination of the pulmonary circulation, pulse oximetry, complete blood count, and serum chemistries and pulmonary function testing with bronchoprovocation in selected patients. MEASUREMENTS AND MAIN RESULTS The 14 follow-up patients were evaluated an average of 23 +/- 23 months (range 3 to 66) following intensive care unit discharge. No child reported a significant alteration in lifestyle or limitation of activities. Physical examinations were generally unremarkable. The room air oxyhemoglobin saturation was > or = 0.98 in all patients. Comparison of chest radiographs at the time of follow-up with those chest radiographs during the period of critical illness showed marked but not complete improvement in all. Electrocardiograms and echocardiograms showed new evidence of left ventricular hypertrophy in one child. The right ventricular preejection period to ejection time ratio was normal in all subjects. Eleven patients completed spirometry. Four patients were normal and the other patients had evidence of restrictive or obstructive disease either at baseline or after bronchoprovocation challenge. Ten children had lung volume measurements. Five children were normal, two showed increased volumes consistent with obstruction, and three showed decreased volumes indicative of restriction. Four of seven patients showed evidence of decreased diffusion capacity. Six of seven patients with evidence of abnormal pulmonary function had a positive response to bronchodilator administration. CONCLUSIONS Although pediatric survivors of acute hypoxemic respiratory failure perceive neither a limitation in lifestyle nor chronic pulmonary morbidity, careful examination of the cardiopulmonary system demonstrates a significant number with abnormal chest radiographs and abnormalities in pulmonary function. These children require careful follow-up and may benefit from use of a bronchodilator.
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Affiliation(s)
- I Weiss
- Department of Pediatrics, New York Hospital-Cornell Medical Center, NY 10021, USA
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Soff GA, Sanderowitz J, Gately S, Verrusio E, Weiss I, Brem S, Kwaan HC. Expression of plasminogen activator inhibitor type 1 by human prostate carcinoma cells inhibits primary tumor growth, tumor-associated angiogenesis, and metastasis to lung and liver in an athymic mouse model. J Clin Invest 1995; 96:2593-600. [PMID: 8675623 PMCID: PMC185963 DOI: 10.1172/jci118323] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Expression of urokinase-type plasminogen activator (uPA) by malignant cells correlates with an aggressive phenotype, including increased invasiveness, tumor-associated angiogenesis, and metastases. Plasminogen activator inhibitor type 1 (PAI-1) is undetectable in cells of some aggressive malignancies, but present in the stroma of tumor-associated microvasculature. This analysis of an athymic mouse model of prostate carcinoma further defines the role of the uPA/PAI-1/plasmin system in primary growth and metastasis. A marked increase in PAI-1 expression was induced in clones of the aggressive human prostate carcinoma line, PC-3, by stable transfection. Primary PC-3 tumors, in mice, were significantly smaller when derived from PAI-1 expressing versus control cells. PAI-1 expression reduced the density of tumor-associated microvasculature by 22-38%. Microscopic metastases were quantitated using stable expression of the chromogenic label (beta-galactosidase) in control and PAI-1 expressing cells. PAI-1 expression resulted in a significant inhibition of lung metastases, and liver metastases. Expression of PAI-1 by malignant prostate cells resulted in a less aggressive phenotype, presumably by inhibition of uPA activity, suggesting pharmacologic or molecular inhibition of uPA activity as a potential therapeutic target.
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Affiliation(s)
- G A Soff
- Division of Hematology/Oncology, Department of Medicine, Northwestern University Medical School, Chicago, Illinois 60611, USA
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Weiss I, Urbaszek A, Wetzig T, Schaldach M. [Simulation of myocardial action potentials of various cell types in relation to neural parameters]. BIOMED ENG-BIOMED TE 1995; 40:64-9. [PMID: 7538801 DOI: 10.1515/bmte.1995.40.3.64] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Action potentials of various myocardial cell types were simulated in a computer model based on current knowledge of the electrical properties of ionic channels and pumps in the ventricular cell membrane and the sarcoplasmic reticulum. The transport mechanisms of sodium, potassium, calcium and chlorine ions through the cell membrane are described mathematically, as is the exchange of calcium between the myoplasm and sarcoplasmic reticulum. Ten ionic channels and three pumps of the cell membrane are taken into account, while three channels and one pump of the sarcoplasmic reticulum are considered in the computations. For the first time, the transient outward potassium current IK,to was simulated, the effect of which on the early repolarisation phase of the action potential was reproducible in the model. Calcium buffers in the myoplasm and the sarcoplasmic reticulum are also considered. From the resulting ionic currents through the channels and pumps, the membrane potential is computed using an equivalent circuit diagram of the cell membrane. In particular the influence of neural activity on channel conductance and the probability of channel patency were taken into account. By means of this model, different shapes of ventricular action potentials were simulated. The action potentials of epicardial cells, M-cells, endocardial cells and Purkinje fibres were accurately simulated. In addition, the effects of sympathetic drive and various drugs were demonstrated in the model as well as the shortening of the action potential duration with increasing stimulation frequency.
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Affiliation(s)
- I Weiss
- Zentralinstitut für Biomedizinische, Technik der Friedrich-Alexander-Universität, Erlangen-Nürnberg
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Weiss I, Wetzig T, Urbaszek A, Schaldach M. Herzkonturenbestimmung in Magnetresonanzschnittbildern mittels zweidimensionaler Filterfunktionen. BIOMED ENG-BIOMED TE 1994. [DOI: 10.1515/bmte.1994.39.s1.338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Weiss P, Weiss I, Zuber M, Ritz R. How many patients with acute dissection of the thoracic aorta would erroneously receive thrombolytic therapy based on the electrocardiographic findings on admission? Am J Cardiol 1993; 72:1329-30. [PMID: 8256718 DOI: 10.1016/0002-9149(93)90311-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- P Weiss
- Department of Internal Medicine, University Hospital Basel, Switzerland
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Vedder H, Weiss I, Holsboer F, Reul JM. Glucocorticoid and mineralocorticoid receptors in rat neocortical and hippocampal brain cells in culture: characterization and regulatory studies. Brain Res 1993; 605:18-24. [PMID: 8467386 DOI: 10.1016/0006-8993(93)91351-r] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Glucocorticoid and mineralocorticoid binding sites were characterized in cell cultures derived from neocortical and hippocampal brain tissue from fetal (E18) rats. Specific and saturable binding was detected in living cells with a sensitive whole cell binding method using [3H]dexamethasone ([3H]DEX) and [3H]aldosterone ([3H]ALDO) (in the presence of RU 28362, a selective glucocorticoid receptor (GR) agonist) as ligands for the measurement of glucocorticoid and mineralocorticoid receptors (MRs), respectively. Specific corticosteroid binding was demonstrated as early as day 4 in culture in neocortical cells, with a time-dependent increase in binding sites during further culturing time. At 7-9 days in vitro, Scatchard analysis of [3H]DEX binding revealed a maximum binding capacity (Bmax) of 83.4 +/- 5.0 fmol/mg protein and a binding affinity (Kd) of 3.6 +/- 0.4 nM in neocortical brain cells. Competition binding studies with [3H]DEX demonstrated a glucocorticoid specificity of receptor sites (relative binding affinity: RU 28362 = DEX > PROG > ALDO). Similar binding characteristics were demonstrated for GRs in cultures derived from fetal hippocampal tissue (Bmax 49.1 +/- 5.8 fmol/mg protein, Kd 3.5 +/- 0.2 nM). Analysis of MRs with [3H]ALDO (+RU 28362) revealed specific and saturable binding in hippocampal cultures, with a Bmax of 8.0 +/- 0.5 fmol/mg protein and a Kd of 0.2 +/- 0.1 nM. Competition studies with [3H]ALDO showed a mineralocorticoid-like pattern of receptor binding (relative binding affinity: CORT = ALDO > PROG > DEX). In addition, small numbers of MRs were detectable in cortex-derived cultures (Bmax: 3.7 +/- 0.8 fmol/mg protein, Kd: 0.3 +/- 0.2 nM).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H Vedder
- Max Planck Institute of Psychiatry, Department of Neuroendocrinology, Munich, FRG
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Cockeram B, Jackson AG, Omlor RE, Srinivasan R, Weiss I. Preparation of TEM foils from Nb-10 a/o Si. Microsc Res Tech 1992; 22:298-300. [PMID: 1504356 DOI: 10.1002/jemt.1070220307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Ductile phase toughened composites contain phases with significantly different physical properties. Consequently, these phases thin at different rates depending on the sample preparation procedure. A new TEM foil preparation method for the ductile phase toughened Nb-10 a/o Si material has been developed. The method involves chemical thinning in a 70% nitric acid/30% hydrofluoric acid solution followed by electropolishing in a 12.5% sulfuric acid/87.5% methanol electrolyte at -40 degrees C. This procedure for making TEM foils results in large thin areas with the minimum of artifacts. Mechanical grinding of a sample followed by either ion milling, dimpling, or electropolishing produced foils with large electron transparent areas, but with uncharacteristic features of the original Nb-10 a/o Si alloy microstructure. These artifacts were identified as dislocations, surface mottling, and antiphase domains.
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Affiliation(s)
- B Cockeram
- Department of Mechanical and Materials Engineering, Wright State University, Dayton, Ohio 45435
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Romao L, Cash F, Weiss I, Liebhaber S, Pirastu M, Galanello R, Loi A, Paglietti E, Ioannou P, Cao A. Human alpha-globin gene expression is silenced by terminal truncation of chromosome 16p beginning immediately 3' of the zeta-globin gene. Hum Genet 1992; 89:323-8. [PMID: 1351037 DOI: 10.1007/bf00220551] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The high level expression of the human alpha-globin genes in erythroid tissue appears to require a set of DNaseI hypersensitive sites located upstream of the human alpha-globin gene cluster. These sequences, termed the locus control region (LCR), include two erythroid specific and a number of less restricted DNaseI hypersensitive sites. In this report we describe an individual with alpha-thalassemia associated with a truncation of the short arm of chromosome 16 that removes the LCR region and inactivates the adjacent intact alpha-globin genes. This genetic study supports the critical role of the LCR in the transcriptional activation of the human alpha-globin gene cluster and substantiates the importance of LCR deletions in the etiology of alpha-thalassemia.
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Affiliation(s)
- L Romao
- Howard Hughes Medical Institute, University of Pennsylvania, Philadelphia 19104
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Saqib M, Weiss I, Mehrotra GM, Clevenger E, Jackson AG, Lipsitt HA. Microstructural and thermal stability of a Ti-43AI alloy containing dispersoids of titanium di-boride. ACTA ACUST UNITED AC 1991. [DOI: 10.1007/bf02646495] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Cockeram B, Saqib M, Omlor R, Srinivasan R, Matson L, Weiss I. Characterization of silicide precipitates in primary Nb phase in Nb - 10% Si in-situ composites. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/0956-716x(91)90199-b] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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