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1.
Nurse Educ Pract ; 57: 103242, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34736079

ABSTRACT

AIM/OBJECTIVE: This study examines the value that learning community activities and interactions produce (immediate value) during the early stage of community development, contributing to scientific insights on value creation. BACKGROUND: Due to the rapidly changing healthcare landscape, nurses and nursing students need to adjust their skills, knowledge and collaboration with colleagues and other disciplines. Learning communities are a promising approach to enhancing professional growth and collaboration, where members find value through participation in the community. DESIGN: For the study, a qualitative design was used. METHODS: A secondary analysis of case study data, collected during the first five sessions of a hospital learning community comprised of nurses, nursing students and a nurse lecturer, was conducted. RESULTS: The analysis revealed immediate value related to five themes: participation, activity, engagement, interaction, and confidence/trust. Members were encouraged to participate in and be involved during activities and interactions, such as asking questions, sharing their experiences and receiving feedback. Members became more familiar and confident in later community sessions, promoting immediate value creation. This was indicated by the different members who became active, took initiative or discussed problems. CONCLUSIONS: It is concluded that the activities and interactions produce value during the early stage of community development but may also grow to include new activities and interactions associated with further community development.


Subject(s)
Education, Nursing, Baccalaureate , Students, Nursing , Feedback , Humans , Learning , Problem Solving
2.
J Plast Reconstr Aesthet Surg ; 74(4): 819-827, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33172821

ABSTRACT

OBJECTIVE: Non-invasive Remote Ischemic Conditioning (RIC) offers an approach to reduce tissue damage in various organs/tissues. Besides attenuation of Ischemia-Reperfusion injury (I/R), beneficial effects on cutaneous microcirculation of free microsurgical flaps have been reported. Given the recency of this technique, there are considerable gaps in the current understanding of its mechanism of action. As a result, clinical transfer of RIC is prolongated in several fields. We aimed to optimize the RIC protocol by examination of different RIC-cycle numbers and its effect on changes of cutaneous microcirculation and duration. METHODS: 80 subjects were divided into groups (1, 3, 5, 7 RIC cycles). RIC was applied via an inflatable tourniquet. Cutaneous microcirculation was continuously assessed at the contralateral anterior lateral thigh utilizing a ©O2C-device continuously. RESULTS: RIC caused significant and sustained changes in microcirculation. Four hours after completion of RIC, a maximum increase of +80.8% (CI 1.395-2.221) in blood flow and +23.5% (CI 1.098-1.372) in tissue oxygen saturation was measured (three-cycle group). A higher number of applied cycles was accompanied with significant higher mean pain. CONCLUSION: Acute improvement of cutaneous microcirculation due to RIC lasted for at least 4 h after completion of the RIC-protocol. Dose-dependent effects of RIC are likely. With regard to the increase in pain, we recommend a RIC protocol of 3 cycles for future clinical application.


Subject(s)
Arm/blood supply , Ischemic Preconditioning/methods , Skin/blood supply , Adult , Female , Healthy Volunteers , Humans , Male , Microcirculation , Oxygen/blood , Tourniquets
3.
Handchir Mikrochir Plast Chir ; 51(2): 111-118, 2019 Apr.
Article in German | MEDLINE | ID: mdl-30763978

ABSTRACT

BACKGROUND: Due to the loss of the natural skin barrier function with reduced immune competence as a result of a plasma loss and the numerous intensive care interventions, burn patients are particularly at risk for infection. STUDY DESIGN: systematic review METHODS: A systematic review of German and English literature between 1990 and 2018 analyzes the epidemiological and diagnostic aspects as well as the therapeutic use of antibiotics in infections of burn patients in clinical trials. RESULTS: A total number of 53 randomized controlled clinical trials met the inclusion criteria. Various types / forms of application of antibiotic prophylaxis in burn wounds were investigated: topically, systemically (generally), systemically (perioperatively), nonabsorbable antibiotics (= selective intestinal decontamination), locally (inhaled) and all forms of administration versus control. Early postburn prophylaxis was studied in low-severity patients (six studies) and severe burn patients (seven studies). Antimicrobial prophylaxis has shown no effectiveness in the prevention of toxic shock syndrome in low grade burns, but can be useful in patients with severe burns in need for mechanical ventilation. Perioperative prophylaxis has been studied in ten studies. CONCLUSION: The benefit of long-term systemic antibiotic prophylaxis in the majority of burn patients is not evident. Mild infections in stable clinical conditions should be closely monitored, while in severe infections, international sepsis guidelines and the Tarragona principle are recommended.


Subject(s)
Anti-Bacterial Agents , Antibiotic Prophylaxis , Burns , Bacterial Infections/prevention & control , Burns/complications , Burns/drug therapy , Humans
4.
Handchir Mikrochir Plast Chir ; 51(4): 309-318, 2019 Aug.
Article in German | MEDLINE | ID: mdl-30278469

ABSTRACT

The development and homeostasis of multicellular organisms depends on a complex cellular interaction between proliferation, migration, differentiation, adhesion, and cell death. Wnt signaling pathways coordinate these different cellular responses. Wnt signaling plays a role as a regulatory pathway in the osteogenic differentiation of mesenchymal stem cells. The Wnt signaling pathway is an attractive therapeutic target with the potential to directly modulate stem cells responsible for the regeneration of skeletal tissue. Recent studies indicate that Wnt ligands are capable of promoting bone growth, suggesting that Wnt factors could be used to stimulate bone healing in osteogenic disorders.


Subject(s)
Bone and Bones , Mesenchymal Stem Cells , Osteogenesis , Wnt Signaling Pathway , Bone and Bones/metabolism , Cell Differentiation , Wnt Proteins
5.
Chirurg ; 90(2): 94-101, 2019 Feb.
Article in German | MEDLINE | ID: mdl-30478483

ABSTRACT

The treatment of choice for soft tissue sarcomas with local involvement is still the complete surgical removal into healthy tissue. The aim of surgery is to achieve tumor-free resection margins in the sense of a R0 resection. No other treatment option can equally replace this important oncological condition. The enormous development in the field of reconstructive plastic surgery and in particular the advances in flap techniques and microsurgery enable limb salvage and the functional reconstruction even in the case of extensive tumors.


Subject(s)
Plastic Surgery Procedures , Sarcoma , Soft Tissue Neoplasms , Surgery, Plastic , Humans , Limb Salvage , Sarcoma/surgery , Soft Tissue Neoplasms/surgery
6.
Scand J Surg ; 108(4): 297-304, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30474468

ABSTRACT

INTRODUCTION: Patients experiencing thermal injuries with an extent of over 20% of total body surface area suffer from systemic catabolic disease. The thermal trauma-induced loss of muscle mass causes a higher incidence for comorbidities and subsequently a higher mortality. In this study, we aimed to investigate the role of myostatin in the interplay with follistatin during muscle cachexia. METHODS: Patients with burn injuries (>10% total body surface area) between the ages of 18 and 75 were prospectively included within the first 48 h after trauma to determine deviations of parameters connected to muscle catabolism. In the chronic state of burn injury (9-12 months after trauma), we re-evaluated myostatin and follistatin concentrations as well as muscle strength of the non-dominant forearm. RESULTS: We were able to show a time-dependent alteration (9-12 months after burn injury) of myostatin with an initial decrease (p < 0.001) and long-term increase (p < 0.001) after thermal injury in blood serum. For follistatin, a reciprocal correlation was observed (r = -0.707, p = 0.001). Accordingly, muscle strength of the non-dominant hand and forearm was significantly decreased 9-12 months after injury in post-burn patients compared with healthy patients with a significant correlation to myostatin levels (r = -0.899, p < 0.001). In addition, initial myostatin serum concentration was predictive for long-term muscle strength impairment. CONCLUSION: With regard to the muscle metabolism after thermal trauma, our data suggest an acute anabolic response, presumably to spare muscle mass, which is converted to catabolic conditions accompanied by muscle strength reduction in the chronic phase. Myostatin plays a crucial role in this orchestration and initial myostatin concentration may predict the long-term muscle strength.


Subject(s)
Burns/blood , Cachexia/blood , Follistatin/blood , Myostatin/blood , Adolescent , Adult , Aged , Biomarkers/blood , Burns/complications , Cachexia/etiology , Female , Humans , Male , Middle Aged , Muscle Strength , Prospective Studies
7.
Nutr Cancer ; 69(2): 340-351, 2017.
Article in English | MEDLINE | ID: mdl-28045549

ABSTRACT

BACKGROUND: The cytostatic effects of the polyphenol curcumin and Viscum album extract (VAE) were assessed in soft-tissue sarcoma (STS) cells. METHODS: Eight human STS cell lines were used: fibrosarcoma (HT1080), liposarcoma (SW872, T778, MLS-402), synovial sarcoma (SW982, SYO1, 1273), and malignant fibrous histiocytoma (U2197). Primary human fibroblasts served as control cells. Cell proliferation, viability, and cell index (CI) were analyzed by BrdU assay, MTT assay, and real-time cell analysis (RTCA). RESULTS: As indicated by BrdU and MTT, curcumin significantly decreased the cell proliferation of five cell lines (HT1080, SW872, SYO1, 1273, and U2197) and the viability of two cell lines (SW872 and SW982). VAE led to significant decreases of proliferation in eight cell lines (HT1080, SW872, T778, MLS-402, SW982, SYO1, 1293, and U2197) and reduced viability in seven STS lines (HT1080, SW872, T778, MLS-402, SW982, SYO1, and 1273). As indicated by RTCA for 160 h, curcumin decreased the CI of all synovial sarcoma cell lines as well as T778 and HT1080. VAE diminished the CI in most of the synovial sarcoma (SW982, SYO1) and liposarcoma (SW872, T778) cell lines as well as HT1080. Primary fibroblasts were not affected adversely by the two compounds in RTCA. CONCLUSION: Curcumin and VAE can inhibit the proliferation and viability of STS cells.


Subject(s)
Curcumin/pharmacology , Plant Extracts/pharmacology , Sarcoma/drug therapy , Viscum album/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Colorimetry , Humans
8.
Handchir Mikrochir Plast Chir ; 48(4): 205-11, 2016 Aug.
Article in German | MEDLINE | ID: mdl-27547928

ABSTRACT

Perioperative management of microsurgery is not well standardised. Due to a lack of evidence, different regimes are established in different microsurgical centres. However, trends towards less aggressive perioperative interventions can be identified in recent years, since treatment algorithms without systematic evidence are being progressively abandoned. The available evidence on perioperative issues, such as temperature control, fluid resuscitation, blood transfusions, application of vasodilators or - pressors, as well as anticoagulants, were discussed during the consensus conference on perioperative management at the annual meeting of the German Speaking Society for Microsurgery of Peripheral Nerves and Vessels. Common basic standards were identified and a consensus was reached that is described in the following manuscript.


Subject(s)
Microsurgery , Peripheral Nerves/surgery , Consensus , Humans
9.
Urologe A ; 55(4): 484-8, 2016 Apr.
Article in German | MEDLINE | ID: mdl-26649739

ABSTRACT

BACKGROUND: Fournier's gangrene is a variant of the necrotizing fasciitis restricted to the perineal and genital region. It presents as an acute life-threatening disease and demands rapid surgical debridement, resulting in large soft tissue defects. Various reconstructive methods have to be applied to reconstitute functionality and aesthetics. The objective of this work is to identify different reconstructive methods in the literature and compare them to our current concepts for reconstructing defects caused by Fournier gangrene. METHODS: Analysis of the current literature and our reconstructive methods on Fournier gangrene. RESULTS: The Fournier gangrene is an emergency requiring rapid, calculated antibiotic treatment and radical surgical debridement. After the acute phase of the disease, appropriate reconstructive methods are indicated. The planning of the reconstruction of the defect depends on many factors, especially functional and aesthetic demands. Scrotal reconstruction requires a higher aesthetic and functional reconstructive degree than perineal cutaneous wounds. In general, thorough wound hygiene, proper pre-operative planning, and careful consideration of the patient's demands are essential for successful reconstruction. CONCLUSIONS: In the literature, various methods for reconstruction after Fournier gangrene are described. Reconstruction with a flap is required for a good functional result in complex regions as the scrotum and penis, while cutaneous wounds can be managed through skin grafting. Patient compliance and tissue demand are crucial factors in the decision-making process.


Subject(s)
Debridement/methods , Emergency Treatment/methods , Fournier Gangrene/diagnosis , Fournier Gangrene/surgery , Plastic Surgery Procedures/methods , Urologic Surgical Procedures , Combined Modality Therapy , Critical Illness , Cystoscopy/methods , Diagnosis, Differential , Diagnostic Techniques, Urological , Emergencies , Emergency Medical Services/methods , Evidence-Based Medicine , Germany , Humans , Male , Surgical Flaps , Treatment Outcome
10.
Clin Anat ; 26(3): 333-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23255348

ABSTRACT

The surgical anatomy of the pelvis is highly complex. Anorectal and urogenital dysfunctions occur frequently after pelvic oncological surgery and are mainly caused by surgical damage of the autonomic nerves. A highly-detailed 3D pelvic model could increase the anatomical knowledge and form a solid basis for a surgical simulation system. Currently, pelvic surgeons still rely on the preoperative interpretation of 2D diagnostic images. With a 3D simulation system, pelvic surgeons could simulate and train different scenes to enhance their preoperative knowledge and improve surgical outcome. To substantially enrich pelvic surgery and anatomical education, such a system must provide insight into the relation between the autonomic network, the lymphatic system, and endopelvic fasciae. Besides CT and MR images, Visible Human Datasets (VHDs) are widely used for 3D modeling, due to the high degree of anatomical detail represented in the cryosectional images. However, key surgical structures cannot be fully identified using VHDs and radiologic imaging techniques alone. Several unsolved anatomical problems must be elucidated as well. Therefore, adequate analysis on a microscopic level is inevitable. The development of a comprehensive anatomical atlas of the pelvis is no straightforward task. Such an endeavor involves several anatomical and technical challenges. This article surveys all existing 3D pelvic models, focusing on the level of anatomical detail. The use of VHDs in the 3D reconstruction of a highly-detailed pelvic model and the accompanying anatomical challenges will be discussed.


Subject(s)
Models, Anatomic , Pelvis/anatomy & histology , Anatomy, Artistic , Atlases as Topic , Humans , Imaging, Three-Dimensional
11.
Br J Surg ; 97(10): 1582-7, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20641063

ABSTRACT

BACKGROUND: The objective of this study was to obtain detailed anatomical information about the lateral lymph nodes, in order to determine whether they might play a role in presacral local recurrence of rectal cancer after total mesorectal excision without lateral lymph node dissection. METHODS: Ten serially sectioned human fetal pelvises were studied at high magnification and a three-dimensional reconstruction of the fetal pelvis was made. RESULTS: Examination of the histological sections and the three-dimensional reconstruction showed that lateral lymph node tissue comprises a major proportion of the pelvic tissue volume. There were no lymph nodes located in the presacral area. Connections between the mesorectal and extramesorectal lymph node system were found in all fetal pelvises, located below the peritoneal reflection on the anterolateral side of the fetal rectum. At this site middle rectal vessels passed to and from the mesorectum, and branches of the autonomic nervous system bridge to innervate the rectal wall. CONCLUSION: The findings of this study support the hypothesis that tumour recurrence might arise from lateral lymph nodes.


Subject(s)
Lymph Nodes/embryology , Neoplasm Recurrence, Local/etiology , Rectal Neoplasms/etiology , Sacrum/embryology , Humans , Neoplasm Recurrence, Local/embryology , Pelvis/embryology , Rectal Neoplasms/embryology , Rectum/innervation
12.
Radiat Res ; 171(1): 118-22, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19138052

ABSTRACT

The first measurements of (63)Ni produced by A-bomb fast neutrons (above approximately 1 MeV) in copper samples from Hiroshima encompassed distances from approximately 380 to 5062 m from the hypocenter (the point on the ground directly under the bomb). They included the region of interest to survivor studies (approximately 900 to 1500 m) and provided the first direct validation of fast neutrons in that range. However, a significant measurement gap remained between the hypocenter and 380 m. Measurements close to the hypocenter are important as a high-value anchor for the slope of the curve for neutron activation as a function of distance. Here we report measurements of (63)Ni in copper samples from the historic Hiroshima Atomic Bomb Dome, which is located approximately 150 m from the hypocenter. These measurements extend the range of our previously published data for (63)Ni providing a more comprehensive and consistent A-bomb activation curve. The results are also in good agreement with calculations based on the current dosimetry system (DS02) and give further experimental support to the accuracy of this system that forms the basis for radiation risk estimates worldwide.


Subject(s)
Copper/chemistry , Fast Neutrons , Nuclear Weapons , Japan , Mass Spectrometry , Nickel/analysis , Radioisotopes/analysis
13.
Radiat Environ Biophys ; 46(4): 327-38, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17828415

ABSTRACT

Those inhabitants of Hiroshima and Nagasaki who were affected by the A-bomb explosions, were exposed to a mixed neutron and gamma radiation field. Few years later about 120,000 survivors of both cities were selected, and since then radiation-induced late effects such as leukemia and solid tumors are being investigated in this cohort. When the present study was initiated, the fast neutron fluences that caused the neutron doses of these survivors had never been determined experimentally. In principle, this would have been possible if radioisotopes produced by fast neutrons from the A-bomb explosions had been detected in samples from Hiroshima and Nagasaki at distances where the inhabitants survived. However, no suitable radioisotope had so far been identified. As a contribution to a large international effort to re-evaluate the A-bomb dosimetry, the concentration of the radionuclide (63)Ni (half-life 100.1 years) has been measured in copper samples from Hiroshima and Nagasaki. These measurements were mainly performed at the Maier-Leibnitz-Laboratory in Munich, Germany, by means of accelerator mass spectrometry. Because the (63)Ni had been produced in these samples by fast A-bomb neutrons via the reaction (63)Cu(n,p)(63)Ni, these measurements allow direct experimental validation of calculated neutron doses to the members of the LSS cohort, for the first time. The results of these efforts have already been published in a compact form. A more detailed discussion of the methodical aspects of these measurements and their results are given in the present paper. Eight copper samples that had been significantly exposed to fast neutrons from the Hiroshima A-bomb explosion were investigated. In general, measured (63)Ni concentrations decreased in these samples with increasing distance to the hypocenter, from 4 x 10(6 ) (63)Ni nuclei per gram copper at 391 m, to about 1 x 10(5 ) (63)Ni nuclei per gram copper at about 1,400 m. Additional measurements performed on three large-distant copper samples from Hiroshima (distance to the hypocenter 1,880-7,500 m) and on three large-distant copper samples from Nagasaki (distance to the hypocenter 3,931-4,428 m) that were not exposed significantly to A-bomb neutrons, suggest a typical background concentration of about 8 x 10(4 ) (63)Ni nuclei per gram copper. If the observed background is accounted for, the results are consistent with state-of-the-art neutron transport calculations for Hiroshima, in particular for those distances where the victims survived and were included in the life span study cohort.


Subject(s)
Copper/analysis , Copper/radiation effects , Nickel/analysis , Nuclear Warfare , Radiation Monitoring/methods , Radioisotopes/analysis , Soil Pollutants, Radioactive/analysis , Cities , Japan , Neutrons , Nickel/radiation effects , Radiation Dosage , Radioisotopes/radiation effects
15.
Eur J Pediatr Surg ; 14(1): 45-50, 2004 Feb.
Article in English | MEDLINE | ID: mdl-15024679

ABSTRACT

The treatment of vesicoureteral reflux (VUR) is still a controversial issue. The efficacy of medical treatment appears to be equal to that of operative procedures in avoiding new formation of renal scars. However, there are generally accepted indications for operative procedures including bilateral high-grade VUR, especially in young patients. Ureteral reimplantation (UCN) is the operative treatment of choice in cases with high-grade VUR. Alternatively in cases with lower-grade VUR, injection of bulking agents under the refluxive orifice can be performed. It is also generally accepted that UCN with extravesical preparation of the ureter and the bladder should not be done bilaterally in a one-stage procedure. Postoperative bladder dysfunction may result due to detrimental neurogenic effects. In this study we report on our operative procedure in cases with bilateral high-grade VUR, during which we perform intra/extravesical UCN (mod. Leadbetter-Politano) of the higher-grade refluxive ureter, and (open) subureteral collagen injection (SCIN) of the lower-grade refluxive orifice as a combined one-stage procedure. In this study 50% of the patients had no VUR on either side after the first combined procedure. 15% of the patients showed significant down-grading of VUR of the injected side. These patients underwent a 2nd endoscopic SCIN. 35% of the patients showed no change of VUR of the injected side after the first procedure; these patients underwent reimplantation of this side in another operation. Accordingly, 50% of patients with bilateral high-grade VUR required a 2nd operative procedure under full anesthesia to achieve loss of VUR on both sides. None of the patients showed bladder dysfunction postoperatively. Mean follow-up after the last operative correction was 29.9 months (6 - 84 months).


Subject(s)
Collagen/administration & dosage , Urologic Surgical Procedures/methods , Vesico-Ureteral Reflux/surgery , Algorithms , Child, Preschool , Cystostomy , Female , Follow-Up Studies , Humans , Male , Reoperation , Time Factors , Ureterostomy , Vesico-Ureteral Reflux/therapy
16.
Nature ; 424(6948): 539-42, 2003 Jul 31.
Article in English | MEDLINE | ID: mdl-12891354

ABSTRACT

Data from the survivors of the atomic bombs serve as the major basis for risk calculations of radiation-induced cancer in humans. A controversy has existed for almost two decades, however, concerning the possibility that neutron doses in Hiroshima may have been much larger than estimated. This controversy was based on measurements of radioisotopes activated by thermal neutrons that suggested much higher fluences at larger distances than expected. For fast neutrons, which contributed almost all the neutron dose, clear measurement validation has so far proved impossible at the large distances (900 to 1,500 m) most relevant to survivor locations. Here, the first results are reported for the detection of 63Ni produced predominantly by fast neutrons (above about 1 MeV) in copper samples from Hiroshima. This breakthrough was made possible by the development of chemical extraction methods and major improvements in the sensitivity of accelerator mass spectrometry for detection of 63Ni atoms (refs 8-11). When results are compared with 63Ni activation predicted by neutron doses for Hiroshima survivors, good agreement is observed at the distances most relevant to survivor data. These findings provide, for the first time, clear measurement validation of the neutron doses to survivors in Hiroshima.


Subject(s)
Dose-Response Relationship, Radiation , Fast Neutrons , Nuclear Warfare , Copper/analysis , Copper/chemistry , Fast Neutrons/adverse effects , Humans , Isotopes , Japan , Nickel/analysis , Radioisotopes , Reproducibility of Results , Sensitivity and Specificity , Survival
17.
Br J Pharmacol ; 136(5): 709-16, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12086980

ABSTRACT

1. Cannabinoids are potent inhibitors of endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxations. We set out to study the mechanism underlying this effect and the possible role of cannabinoid-induced changes in intercellular gap junction communication. 2. In cultured endothelial cells, Delta(9)-tetrahydrocannabinol (Delta(9)-THC) and the cannabinoid receptor agonist HU210, increased the phosphorylation of extracellular regulated kinases 1/2 (ERK1/2) and inhibited gap junctional communication, as determined by Lucifer Yellow dye transfer and electrical capacity measurements. 3. Delta(9)-THC elicited a pronounced increase in the phosphorylation of connexin 43, which was sensitive to PD98059 and U0126, two inhibitors of ERK1/2 activation. Inhibition of ERK1/2 also prevented the Delta(9)-THC-induced inhibition of gap junctional communication. 4. Delta(9)-THC prevented both the bradykinin-induced hyperpolarization and the nitric oxide and prostacyclin-independent relaxation of pre-contracted rings of porcine coronary artery. These effects were prevented by PD98059 as well as U0126. 5. In the absence of Delta(9)-THC, neither PD98059 nor U0126 affected the NO-mediated relaxation of coronary artery rings but both substances induced a leftward shift in the concentration - relaxation curve to bradykinin when diclofenac and N(omega)nitro-L-arginine were present. Moreover, PD98059 and U0126 prolonged the bradykinin-induced hyperpolarization of porcine coronary arteries, without affecting the magnitude of the response. 6. These results indicate that the cannabinoid-induced activation of ERK1/2, which leads to the phosphorylation of connexin 43 and inhibition of gap junctional communication, may partially account for the Delta(9)-THC-induced inhibition of EDHF-mediated relaxation. Moreover, the activation of ERK1/2 by endothelial cell agonists such as bradykinin, appears to exert a negative feedback inhibition on EDHF-mediated responses.


Subject(s)
Cannabinoids/pharmacology , Dronabinol/analogs & derivatives , Endothelium, Vascular/drug effects , Gap Junctions/drug effects , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinases/metabolism , Animals , Biological Factors/metabolism , Dronabinol/pharmacology , Endothelium, Vascular/enzymology , Gap Junctions/enzymology , Humans , In Vitro Techniques , Mitogen-Activated Protein Kinase 3 , Neural Inhibition/drug effects , Neural Inhibition/physiology , Swine
18.
Biol Psychiatry ; 50(9): 725-7, 2001 Nov 01.
Article in English | MEDLINE | ID: mdl-11704081

ABSTRACT

BACKGROUND: Preliminary evidence suggests that demented patients may experience beneficial effects of light therapy. The authors tested whether bright light therapy (BLT) is capable of improving cognitive functions in patients with Alzheimer-type dementia (AD) or vascular dementia (VD). METHODS: Twenty-three patients with AD or VD were randomly assigned to either evening BLT or dim light therapy (DLT). Effects of light therapy on cognitive functions were assessed before and after light therapy using Mini-Mental State Examination (MMSE) scores. Body temperature rhythm (BTR) was additionally recorded pre- and posttreatment. RESULTS: Irrespective of their diagnosis, patients treated with BLT (p =.0012) but not with DLT (p =.73) showed a statistically significant increase in MMSE total scores after light therapy. Evening BLT simultaneously induced a significant phase delay of 56 min on BTR (p =.025). CONCLUSION: Our preliminary results suggest that short-term evening BLT may exert beneficial effects on cognitive functioning in patients with dementia.


Subject(s)
Alzheimer Disease/therapy , Cognition Disorders/diagnosis , Dementia, Vascular/therapy , Phototherapy , Aged , Aged, 80 and over , Body Temperature/physiology , Female , Humans , Male , Neuropsychological Tests
20.
Health Phys ; 79(4): 358-64, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11007457

ABSTRACT

After the release of the present dosimetry system DS86 in 1987, measurements have shown that DS86 may substantially underestimate thermal neutron fluences at large distances (>1,000 m) from the hypocenter in Hiroshima. This discrepancy casts doubts on the DS86 neutron source term and, consequently, the survivors' estimated neutron doses. However, the doses were caused mainly by fast neutrons. To determine retrospectively fast neutron fluences in Hiroshima, the reaction 63Cu(n, p)63Ni can be used, if adequate copper samples can be found. Measuring 63Ni (half life 100 y) in Hiroshima samples requires a very sensitive technique, such as accelerator mass spectrometry (AMS), because of the relatively small amounts of 63Ni expected (approximately 10(5)-10(6) atoms per gram of copper). Experiments performed at Lawrence Livermore National Laboratory have demonstrated in 1996 that AMS can be used to measure 63Ni in Hiroshima copper samples. Subsequently, a collaboration was established with the Technical University of Munich in view of its potential to perform more sensitive measurements of 63Ni than the Livermore facility and in the interest of interlaboratory validation. This paper presents the progress made at the Munich facility in the measurement of 63Ni by AMS. The Munich accelerator mass spectrometry facility is a combination of a high energy tandem accelerator and a detection system featuring a gas-filled magnet. It is designed for high sensitivity measurements of long-lived radioisotopes. Optimization of the ion source setup has further improved the sensitivity for 63Ni by reducing the background level of the 63Cu isobar interference by about two orders of magnitude. Current background levels correspond to a ratio of 63Ni/Ni<2x10(-14) and suggest that, with adequate copper samples, the assessment of fast neutron fluences in Hiroshima and Nagasaki is possible for ground distances of up to 1500 m, and--under favorable conditions--even beyond. To demonstrate this capability, we have measured successfully 6Ni/Ni ratios as low as (3.5 +/- 0.6) x 10(-13). The latter are, based on DS86, representative of a ratio expected from a typical Hiroshima copper sample at about 1,300-m ground range.


Subject(s)
Fast Neutrons , Nickel/analysis , Nuclear Warfare , Radioisotopes/analysis , Survivors , Body Burden , Calibration , Copper/analysis , Humans , Japan , Mass Spectrometry/methods , Particle Accelerators , Radiation Monitoring/methods , Radioactive Fallout
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