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1.
Ann Biomed Eng ; 44(4): 1310-20, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26139296

ABSTRACT

Accident-induced liver trauma is a significant human health concern, as this organ is readily injured during periods at which the abdominal region is compromised. In this work, electromagnetic thermotherapy was successfully developed and employed in vitro and in vivo to treat livers that had been lacerated. Briefly, a new hemostasis plug was integrated with an electromagnetic thermotherapy system (ETS) to perform surgery on lacerated livers. The high-frequency, alternating electromagnetic field (EMF) was generated by the ETS and was shown to induce a pre-set temperature increase within the hemostasis plug embedded in the target tissue. In order to prevent overheating and maintain a constant hemostasis temperature, a temperature feedback control system was utilized. The effect of the intensity of the EMF on the heating capacity of the ETS-hemostasis system was first explored. Furthermore, the relationship between the coagulation zone and operating temperature were investigated in vitro. By utilizing the temperature feedback control system, the hemostasis plug could be heated to a specific temperature for efficient hemostasis. With this approach, the optimal treatment temperature and time were investigated for liver laceration. Lacerated livers from New Zealand white rabbits were successfully treated with the hemostasis plug and ETS within a short period of time. When compared with the traditional perihepatic packing approach, the volume of blood loss from liver laceration surgeries treated by ETS has been dramatically reduced by 83%, suggesting a high therapeutic potential for this system.


Subject(s)
Electromagnetic Fields , Hemostasis, Surgical , Hyperthermia, Induced , Lacerations/therapy , Animals , Blood Loss, Surgical/prevention & control , Liver , Rabbits
2.
IEEE Trans Biomed Eng ; 61(11): 2733-9, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25055378

ABSTRACT

Thermal ablation by using electromagnetic thermotherapy (EMT) has been a promising cancer modality in recent years. It has relatively few side effects and has therefore been extensively investigated for a variety of medical applications in internal medicine and surgery. The EMT system applies a high-frequency alternating electromagnetic field to heat up the needles which are inserted into the target tumor to cause tumor ablation. In this study, a new synchronized-coil EMT system was demonstrated, which was equipped with two synchronized coils and magnetic field generators to provide a long-range, penetrated electromagnetic field to effectively heat up the needles. The heating effect of the needles at the center of the two coils was first explored. The newly designed two-section needle array combined with the synchronized-coil EMT system was thus demonstrated in the in vitro and in vivo animal experiments. Experimental data showed that the developed system is promising for minimally invasive surgery since it might provide superior performance for thermotherapy in cancer treatment.


Subject(s)
Ablation Techniques/instrumentation , Electromagnetic Fields , Hyperthermia, Induced/instrumentation , Needles , Ablation Techniques/methods , Animals , Equipment Design , Liver/pathology , Liver/radiation effects , Liver/surgery , Swine
3.
Ann Biomed Eng ; 42(1): 86-96, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23990331

ABSTRACT

Thermal ablation has been a promising method to remove the cancerous tissues. Electromagnetic-based thermotherapy has been extensively investigated for a variety of medical applications recently. In this study, a prototype electromagnetic thermotherapy system has been developed with a new coil design and a two-section needle. The coil can generate an alternating electromagnetic field (EMF) with a deep penetration depth to remotely heat the needle which is located up to 15 cm away, enabling percutaneous thermal ablation. Several important parameters, including the heating effects of the needle at different positions, the intensity of the EMF and the induced temperature distribution on the surrounding tissue, are first explored. An in vitro animal experiment has also been performed which shows EMF-induced ablation in a porcine liver by the needle. Furthermore, an in vivo experiment on an animal model (a New Zealand white rabbit) is also conducted in the study. Thus, the two-section needle combined with the coil-generated EMF has been demonstrated to be a promising thermotherapy system for percutaneous thermal ablation.


Subject(s)
Electromagnetic Fields , Hot Temperature , Hyperthermia, Induced/instrumentation , Hyperthermia, Induced/methods , Models, Biological , Animals , Rabbits , Swine
4.
IEEE Trans Biomed Eng ; 61(2): 598-605, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24158468

ABSTRACT

Thermotherapy has been a promising method to treat tumor. In recent years, electromagnetic thermotherapy (EMT) has been extensively investigated and holds the potential for a variety of medical applications including for cancer treatment when combined with minimally invasive surgery approach. In this study, an alternating electromagnetic frequency was provided by an EMT system to heat up stainless steel needle arrays which were inserted into the target tumor to a high temperature, therefore leading to local ablation of the tumor. A new two-section needle-array apparatus was further demonstrated to encompass the tumor to prevent the tumor cells to spread after the treatment process. By using the needle-array insertion apparatus, there is no limitation of the treatment area; this method could, therefore, be applied for tumors that are larger than 6 cm. It was first successfully demonstrated in the in vitro experiments on porcine livers. Then an in vivo experiment was directly conducted on pigs. The two-section needle array incorporated with the needle-array apparatus and EMT was demonstrated to be promising for no-touch isolation treatment of cancerous tumors.


Subject(s)
Hyperthermia, Induced/instrumentation , Minimally Invasive Surgical Procedures/instrumentation , Needles , Animals , Electromagnetic Radiation , Hyperthermia, Induced/methods , Liver/surgery , Minimally Invasive Surgical Procedures/methods , Swine
5.
Article in English | MEDLINE | ID: mdl-24288566

ABSTRACT

The effects of apigenin on the expression of VEGF in uveal melanoma cells have not been reported. We studied this effect and relevant signaling pathways in two human uveal melanoma cell lines (SP6.5 and C918). ELISA assay revealed that the constitutive secretion of VEGF by uveal melanoma cells was 21-fold higher than that in normal uveal melanocytes. Apigenin at subtoxic levels (1-5 µ M) significantly suppressed the secretion of VEGF in a dose- and time-dependent manner in melanoma cells. VEGF levels in the conditioned culture media from SP6.5 and C918 cell lines treated with 5 µ M apigenin for 24 h reduced to 29% and 21% of those in cells not treated with apigenin, respectively. RT-PCR analysis found that apigenin also decreased the expression of VEGF mRNA in melanoma cells. ELISA study of various signal pathways showed that apigenin significantly decreased phosphorylated Akt and ERK1/2 but increased phosphorylated JNK1/2 and p38 MAPK levels in melanoma cells. PI3K/Akt or ERK1/2 inhibitors significantly decreased, but JNK1/2 and p38 MAPK inhibitors did not influence the secretion of VEGF by melanoma cells, suggesting that apigenin suppresses the secretion of VEGF mainly through the inhibition of PI3K/Akt and ERK1/2 pathways.

6.
IEEE Trans Biomed Eng ; 59(3): 824-31, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22194233

ABSTRACT

Electromagnetic thermotherapy has been extensively investigated recently and may become a new surgical modality for a variety of medical applications. It applies a high-frequency alternating magnetic field to heat up magnetic materials inserted within the human body to generate tissue coagulation or cell apoptosis. Using a new procedure with dual-row needle arrays under an electromagnetic thermotherapy system with a feedback temperature control system, this study demonstrates bloodless porcine liver resection, which is challenging using existing methods. In vitro experiments showed that hollowed, stainless-steel needles could be heated up to more than 300 °C within 30 s when centered under the induction coils of the electromagnetic thermotherapy system. In order to generate a wide ablation zone and to prevent the dual-row needle arrays from sticking to the tissue after heating, a constant temperature of 120 °C was applied using a specific treatment protocol. The temperature distribution in the porcine livers was also measured to explore the effective coagulation area. Liver resection was then performed in Lan-Yu pigs. Experimental results showed that seven pigs underwent liver resection without bleeding during surgery and no complications afterward. The dual-row needle arrays combined with the electromagnetic thermotherapy system are thus shown to be promising for bloodless tissue resection.


Subject(s)
Blood Loss, Surgical/prevention & control , Hepatectomy/instrumentation , Hyperthermia, Induced/instrumentation , Liver/surgery , Magnetics/instrumentation , Needles , Animals , Electromagnetic Fields , Equipment Design , Liver/pathology , Models, Animal , Swine
7.
Article in English | MEDLINE | ID: mdl-22254653

ABSTRACT

This case study centered on the effects of Music Therapy (MT) on vegetative state (VS) patients for a continuous 41-day experiment with electrocardiogram (ECG) recorded. Mahler's Second Symphony was used for this MT. There are various elements in Mahler's second symphony, with string, wind, drum, and even voice; providing the subject a strong and dynamic stimulation. There are some significant changes after 14-day stimulation: both standard deviation of all normal RR intervals (SDNN) and root mean square successive differences (RMSSD) in heart rate variability of the subject increased, indicating the activity of the cardiovascular system was enhanced. Although there's only one subject in this experiment, the results are still encouraging.


Subject(s)
Heart Rate , Music Therapy/methods , Persistent Vegetative State/nursing , Persistent Vegetative State/physiopathology , Adult , Humans , Male
8.
J Gastroenterol Hepatol ; 25(9): 1578-86, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20796158

ABSTRACT

BACKGROUND AND AIM: Thrombocytopenia due to hypersplenism is usually a serious condition in cirrhotic patients who have undergone invasive procedures. We designed a new treatment method using a high-frequency alternating electromagnetic force to treat the disease condition in a rat model. METHODS: Sprague-Dawley rats were given thioacetamide in drinking water and injected with methylcellulose intraperitoneally to create a cirrhotic hypersplenism model. Spleen volume was determined using the Carlson method. The Control Group consisted of 14 rats, 15 weeks old, that were used to determine the normal platelet count and normal spleen size. Experimental Group I, consisting of 15 rats, received electromagnetic thermoablation of their spleens, after which the spleen was returned to the abdomen. Group II consisted of 13 rats, receiving the same electromagnetic thermoablation as Group I, but the ablated portion was removed. Group III consisted of 14 rats receiving total splenectomies. RESULTS: Cirrhotic hypersplenism was confirmed during laparotomy and pathological examination. Spleen volume enlarged from 1513 +/- 375 mm(3) (Control Group) to 7943 +/- 2822 mm(3) (experimental groups). Platelet counts increased from 0.35 +/- 0.21 x 10(6)/mm(3) to 0.87 +/- 0.24 x 10(6)/mm(3) for Group I, from 0.52 +/- 0.23 x 10(6)/mm(3) to 1.10 +/- 0.20 x 10(6)/mm(3) for Group II, and from 0.47 +/- 0.23 x 10(6)/mm(3) to 1.18 +/- 0.26 x 10(6)/mm(3) for Group III. No rats died due to the treatment in any of the experimental groups. CONCLUSIONS: Our animal model performed successfully and our proposed electromagnetic thermotherapy effectively treated thrombocytopenia due to cirrhotic hypersplenism.


Subject(s)
Catheter Ablation/methods , Electromagnetic Phenomena , Hypersplenism/surgery , Liver Cirrhosis, Experimental/complications , Splenectomy , Thrombocytopenia/surgery , Animals , Hypersplenism/chemically induced , Hypersplenism/complications , Hypersplenism/pathology , Liver Cirrhosis, Experimental/chemically induced , Male , Methylcellulose , Platelet Count , Rats , Rats, Sprague-Dawley , Thioacetamide , Thrombocytopenia/blood , Thrombocytopenia/etiology , Time Factors
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