• Title/Summary/Keyword: Tumor oxygenation

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Catastrophic catecholamine-induced cardiomyopathy rescued by extracorporeal membrane oxygenation in recurrent malignant pheochromocytoma

  • Min, Daniel
    • Journal of Yeungnam Medical Science
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    • v.36 no.3
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    • pp.254-259
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    • 2019
  • Pheochromocytoma (PCC) is a rare catecholamine-producing tumor with the incidence in hypertension of 0.1-0.6%. PCC crisis is an endocrine emergency that can lead to hemodynamic disturbance and organ failure such as catecholamine-induced cardiomyopathy. The circulatory collapse caused by it often requires mechanical support. The author reports an unusual case in which a patient who previously underwent surgery for malignant PCC developed catecholamine-induced cardiomyopathy, and successfully recovered using extracorporeal membrane oxygenation.

Biphasic Tumor Oxygenation during Respiratory Challenge may Predict Tumor Response during Chemotherapy

  • Lee, Songhyun;Jeong, Hyeryun;Anguluan, Eloise;Kim, Jae Gwan
    • Current Optics and Photonics
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    • v.2 no.1
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    • pp.1-6
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    • 2018
  • Our previous study showed that switching the inhaled gas from hypoxic gas to hyperoxic gas for 10 minutes increased tumor oxygenation and that the magnitude of oxyhemoglobin increase responded earlier than tumor volume change after chemotherapy. During 10 minutes of inhaled-oxygen modulation, oxyhemoglobin concentration first shows a rapid increase and then a slow but gradual increase, which has been fitted with a double-exponential equation in this study. Two amplitude values, amplitudes 1 and 2, respectively represent the magnitudes of rapid and slow increase of oxyhemoglobin. The trends of changes in amplitudes 1 and 2 were different, depending on tumor volume when chemotherapy started. However, both amplitudes 1 and 2 changed earlier than tumor volume, regardless of when chemotherapy was initiated. These results imply that by observing amplitude 1 changes post chemotherapy, we can reduce the time of a respiratory challenge from 10 minutes to less than 2 minutes, to see the chemotherapy response. We believe that by reducing the time of the respiratory challenge, we have taken a step forward to translating our previous study into clinical application.

Adrenal incidentaloma: a case of asymptomatic pheochromocytoma

  • Park, Sang Yoong;Rim, Jong Cheol;Cho, Hyun Chul;Lee, Yoon Chan;Kim, Jung A;Choi, So Ron
    • Kosin Medical Journal
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    • v.33 no.2
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    • pp.215-222
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    • 2018
  • An incidentaloma is a tumor found incidentally without clinical symptoms or suspicion; the lesion may be adrenal, pituitary, or thyroidal. We report the case of an asymptomatic individual with preoperatively undiagnosed pheochromocytoma (size: 4.86 cm) that was revealed using elective nonadrenal surgical procedures. The patient demonstrated peri- and post-operative hypertensive crisis and tachycardia. Three days after the dramatic onset of symptoms, the patient expired due to pulmonary edema, multiple organ failure, and terminal sepsis, despite administration of extracorporeal membrane oxygenation-assisted cardiopulmonary resuscitation. A left medial kidney mass obtained at autopsy confirmed pheochromocytoma.

Role of Blood Flow vs. $O_{2}$ Consumption in Nicotinamide-induced Increase $pO_{2}$ in a Murine Tumor (Nicotinamide에 의한 종양내 산소 분압의 증가에 있어서 혈류 또는 산소 소모의 역할)

  • Lee Intae;Demhartner Thomas J.;Cho Moon-June
    • Radiation Oncology Journal
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    • v.12 no.1
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    • pp.17-25
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    • 1994
  • We evaluated the effect of nicotinamide on cellular $O_{2}$ consumption and metabolic status i.e., adenylate phosphates and $NAD^{+}$in-vitro, and changes in blood flow in-vivo, to determine whether changes in cellular metabolism or increased oxygen availability, was responsible for increased tumor oxygenation. Thirty min, pre-incubation of cells with$\∼$4mM (= 500mg/kg) nicotinamide resulted in no change in cellular $O_{2}$ consumption. Similarly neither the adenylate Phosphates nor the cellular $NAD^{+}$levels were altered in the presence of $\∼$4mM nicontinamide. In-vivo, nicotinamide (500mg/kg) increased $O_{2}$ availability as estimated by changes in relative tumor blood flow (RBC flux). The changes in RBC flux measured by the laser Doppler method, were tumor volume dependent and increased from$\∼$35$ \% $ in$\∼$ 150$mm_{3}$tumors to$\∼$~75$ \% $ in$\∼$500$mm^{3}$ tumors. In conclusion, these observations indicate a reduction in local tissue $O_{2}$ consumption is not a mechanism of improved tumor oxygenation by nicotinamide in FSa II murine tumor model. The primary mechanism of increased $pO_{2}$ appears to be an increased local tumor blood flow.

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Enhancement of in vivo Radiosensitization by Combination with Pentoxifylline and Nicotinamide (Pentoxifylline과 Nicotinamide의 병용에 의한 생체내 방사선 감수성 증강 효과)

  • Lee Intae;Cho Moon-June
    • Radiation Oncology Journal
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    • v.9 no.1
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    • pp.7-15
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    • 1991
  • Pentoxifylline (PENTO) has been known to improve RBC fluidity, and thus improve the flux of RBC through narrow capillaries. Additionally, PENTO also decreases the $O_2$ affinity of hemoglobin by increasing 2,3-DPG levels, thereby increasing the $O_2$ release from RBC. Nicotinamide (NA) has been reported to decrease the number of acutely hypoxic cells in tumors by temporarily increasing tumor blood flow. Therefore, the purpose of this study was to examine whether the combination of PENTO and NA (PENTO+NA) would reduce the radioresistance of the Fsall murine fibrosarcoma by oxygenating the hypoxic cells. We obsewed a significantly enhanced radiation-induced growth delay of the FSaII tumors by PENTO+NA. Thus the enhancement ratio was between 2.5 and 2.8 in growth delay assay. The $TCD_{50}$ of control tumors was about 57 Gy, but that of PENTO+NA treated tumors was about 32Gy. Thus $TCD_{50}$ was modified by a factor of 1.8. We also observed that PENTO+NA exerted no effect on the radiation-induced skin damage after the legs without bearing tumors were exposed to X-irradiation. In order to clarify radiosensitizing effects of PENTO+ NA, changes in tumor blood flow and intratumor pOf were measured using laser Doppler flowmetry and $O_2$ microelectrode methods. The tumor blood flow significantly increased at 10 min. after injection of PENTO+ NA. Furthermore, we also found that PENTO+ NA significantly increased intratumor $pO_2$ from 8 to 19 mmHg. We concluded that PENTO+MA was far more effective than NA alone or PENTO alone. The increase in the response of tumors in vivo to X-irradiation appeared to be due mainly to an increase in the tumor oxygenation. Further studies using various concentrations of PENTO alone and in combination with NA to obtain better sequencing and maximal radiosensitization are warranted.

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Validation of Nafamostat Mesilate as an Anticoagulant in Extracorporeal Membrane Oxygenation: A Large-Animal Experiment

  • Han, Sung Joon;Han, Woosik;Song, Hee-Jung;Kim, Cuk-Seong;Jeong, Seong-Mok;Kang, Min Woong
    • Journal of Chest Surgery
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    • v.51 no.2
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    • pp.114-121
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    • 2018
  • Background: Unfractionated heparin is commonly used for anticoagulation in extracorporeal membrane oxygenation (ECMO). Several studies have shown that nafamostat mesilate (NM) has comparable clinical outcomes to unfractionated heparin. This study compared anticoagulation with NM and heparin in a large-animal model. Methods: Beagle dogs (n=8; weight, 6.5-9 kg) were placed on venovenous ECMO. Blood samples were taken every hour and the following parameters were compared: hemoglobin level, activated partial thromboplastin time (aPTT), thromboelastography (TEG) data, platelet function, and inflammatory cytokine levels. Results: In both groups, the aPTT was longer than the baseline value. Although the aPTT in the NM group was shorter than in the heparin group, the TEG parameters were similar between the 2 groups. Hemoglobin levels decreased in both groups, but the decrease was less with NM than with heparin (p=0.049). Interleukin $(IL)-1{\beta}$ levels significantly decreased in the NM group (p=0.01), but there was no difference in the levels of tumor necrosis factor alpha or IL-10 between the 2 groups. Conclusion: NM showed a similar anticoagulant effect to that of unfractionated heparin, with fewer bleeding complications. NM also had anti-inflammatory properties during ECMO. Based on this preclinical study, NM may be a good alternative candidate for anticoagulation in ECMO.

IMPLANTS IN IRRADIATED BONE (방사선 조사받은 악골에서의 임플란트)

  • Kim, Yong-Kack;Park, Hyung-Kook;Hyun, Jae-Hoon;Kim, Jae-Hwan
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.19 no.2
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    • pp.143-148
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    • 1997
  • Cancer therapy for the head and neck malignoncy by surgery, radiotherapy, or combined modalities may cause substantial aesthetic and functional problems for the patient. The placement of osseointegrated implants into irradiated bone should only be performed when the predictability of achieving and maintaining osseointegration is high and the risk of developing of osteoradionecrosis is low. There are many benefits that irradiated patients may gain from the use of implants. A successful implant-retained prosthesis is dependent upon the implants attaining osseointegraton and then sustaining it during functional loads. The use of implants in irradiated patients requires high implant success rates that are acceptable to warrant their use. We report a case and review the literatures about implants in irradiated bone. In that case, the patient were undergone tumor resection and inner-table mandiblectomy due to squamous cell carcinoma of lower posterior gingiva. But 5 year later, the tumor were recurred, we resected the tumor and applied the radiation therapy. After then, we installed four IMZ implants after hyperbaric oxygenation, and made prosthesis using those implants. Until now they don't have any complications.

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In vivo functional photoacoustic imaging (나노초 레이져를 이용한 광-초음파 이미지 결상법)

  • Oh, Jung-Taek;Li, Meng-Lin;Song, Kwang-Hyun;Xie, Xueyi;Stoica, George;Wang, Lihong V.
    • Proceedings of the Optical Society of Korea Conference
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    • 2006.02a
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    • pp.359-360
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    • 2006
  • Functional photoacoustic tomography is a new non-invasive imaging modality, and it is emerging as a very practical method for imaging biological tissue structures by means of laser-induced ultrasound. Structures with high optical absorption, such as blood vessels, can be imaged with the spatial resolution of ultrasound, which is not limited by the strong light scattering in biological tissues. By varying wavelengths of the laser light and acquiring photoacoustic images, optical absorption spectrum of each image pixel is found. Since the biochemical constituents of tissues determine the spectrum, useful functional information like oxygen saturation ($SO_2$) and total haemoglobin concentration (HbT) can be extracted. In this study, as a proof-of-principle experiment, hypoxic brain tumor vasculature and traumatic brain injury (TBI) of small animal brain are imaged with functional photoacoustic tomography. High resolution brain vasculature images of oxygen saturation and total hemoglobin concentration are provided to visualize hypoxic tumor vasculature, and hemorrhage on the cortex surface by the TBI.

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A study on the tumor induced microvasculature using hyperspectral imaging system (초분광 이미징 시스템을 이용한 암 혈관 분석에 대한 연구)

  • Choe, Se-woon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.622-624
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    • 2015
  • Tumor hypoxia caused by the unique characteristics of solid tumor sites such as lowered vascular density, irregular vasculature, longitudinal oxygen gradient, and unbalanced oxygen consumption has decreased therapeutic efficacy in several clinical trials such as radiation, chemotherapy, and surgery. Hence, tumor oxygenation studies at microvascular levels are important to provide better understanding of the complexity of microvasculature oxygen transport and exchange with tissue. However, polarographic microelectodes, was employed to measure $pO_2$ at the microvasculature level, but it is difficult to perform and does not provide significant spatial and temporal information of oxygen delivery. In this research, we introduce the hyperspectral imaging system able to provide a wide range of vascular characteristics by spatial maps on hemoglobin saturation information for better understanding of the relationship between blood oxygen delivery, hypervascularity, aberrant angiogenesis at microvasculature levels during tumor growth.

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Molecular Nuclear imaging of Angiogenesis (혈관신생 분자핵의학 영상)

  • Lee, Kyung-Han
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.2
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    • pp.171-174
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    • 2004
  • Angiogenesis, the formation of new capillaries from existing vessels, increases oxygenation and nutrient supply to ischemic tissue and allows tumor growth and metastasis. As such, angiogenesis targeting provides a novel approach for cancer treatment with easier drug delivery and less drug resistance. Therapeutic anti-angiogenesis has shown impressive effects in animal tumor models and are now entering clinical trials. However, the successful clinical introduction of this new therapeutic approach requires diagnostic tools that can reliably measure angiogenesis in a noninvasive and repetitive manner. Molecular imaging is emerging as an exciting new discipline that deals with imaging of disease on a cellular or genetic level. Angiogenesis imaging is an important area for molecular imaging research, and the use of radiotracers offers a particularly promising technique for its development. While current perfusion and metabolism radiotracers can provide useful information related to tissue vascularity, recent endeavors are focused on the development of novel radioprobes that specifically and directly target angiogenic vessels. Presently available proges include RGD sequence containing peptides that target ${\alpha}_v\;{\beta}_3$ integrin, endothelial growth factors such as VEGF or FGF, metalloptoteinase inhibitors, and specific antiangiogenic drugs. It is now clear that nuclear medicine techniques have a remarkable potential for angiogenesis imaging, and efforts are currently continuing to develop new radioprobes with superior imaging properties. With future identification of novel targets, design of better probes, and improvements in instrumentation, radiotracer angiogenesis imaging promises to play an increasingly important role in the diagnostic evaluation and treatment of cancer and other angiogenesis related diseases.