Biomedical subjects

K Ataka

Publications and source records attributed to K Ataka.

At least 19 recordsLinked to original sources

PubMed2003

Vibrational spectroscopy of an algal Phot-LOV1 domain probes the molecular changes associated with blue-light reception.

The LOV1 domain of the blue light Phot1-receptor (phototropin homolog) from Chlamydomonas reinhardtii has been studied by vibrational spectroscopy. The FMN modes of the dark state of LOV1 were identified by preresonance Raman spectroscopy and assigned to molecular vibrations. By comparing the blue-light-induced FTIR difference spectrum with the preresonance Raman spectrum, most of the differences are due to FMN modes. Thus, we exclude large backbone changes of the protein that might occur during the phototransformation of the dark state LOV1-447 into the putative signaling state LOV1-390. Still, the presence of smaller amide difference bands cannot be excluded but may be masked by overlapping FMN modes. The band at 2567 cm(-1) is assigned to the S-H stretching vibration of C57, the residue that forms the transient thio-adduct with the chromophore FMN. The occurrence of this band is evidence that C57 is protonated in the dark state of LOV1. This result challenges conclusions from the homologous LOV2 domain from oat that the thiolate of the corresponding cysteine is the reactive species.

Animals↗

PubMed2001

Hepatocellular carcinoma with a sarcomatous appearance: report of a case.

A 59-year-old man was admitted with general fatigue, an epigastric mass, and remittent fever. Radiological examinations disclosed a huge solid-to-cystic mass in the right lobe of the liver, and the mass severely compressed the right diaphragm, the inferior vena cava, and the right atrium. In addition, the patient suffered from chronic hepatitis; however, the serum alpha-fetoprotein, carcinoembryonic antigen, and PIVKA II levels were all within the normal ranges. The serum C-reactive protein level was 7.71mg/dl. With a clinical diagnosis of a malignant hepatic tumor invading the right diaphragm, surgery was performed. The tumor originated from segments IV and VII of the liver, was well defined, and grew extrahepatically. The tumor was resected using an ultrasonic cavitational aspirator together with the infiltrated right diaphragm. The resected tumor measured 23 x 13 x 23cm in size and weighed 3,700 g. Histologically, the tumor was found to consist of hepatocellular carcinomatous component and sarcomatous component. In the sarcomatous component, spindle-shaped cells which were positive for the immunohistochemical localization of vimentin, alpha-smooth muscle actin, and keratin were identified. The postoperative course was uneventful. The value of the serum C-reactive protein returned to within the normal range, and the patient became afebrile. The patient received a postoperative combination chemotherapy (etoposide, epirubicin, and cisplatin), and remains well with no signs of recurrence 12 months after the operation.

Carcinoma, Hepatocellular↗

PubMed2001

Surgical treatment of an aneurysm in the right aortic arch with aberrant left subclavian artery.

A saccular aneurysm in the right-sided aortic arch with aberrant left subclavian artery is an uncommon disease, and surgical treatment is complicated. Three patients with Edwards type III-B right aortic arch and enlargement of the Kommerell's diverticulum underwent operations. Right thoracotomy was the preferred approach for this lesion and partial cardiopulmonary bypass is a safe and simple procedure when the aortic arch has mild atherosclerosis.

Aorta, Thoracic↗

PubMed2001

Long-term production of erythropoietin after electroporation-mediated transfer of plasmid DNA into the muscles of normal and uremic rats.

The anemia associated with chronic renal failure is one of the best target diseases for erythropoietin (Epo) gene transfer. We previously reported a short-term (1 month) study of continuous rat Epo delivery by muscle-targeted gene transfer of plasmid DNA expressing rat Epo (pCAGGS-Epo) using in vivo electroporation in normal rats. Here, we performed a long-term pharmacokinetic study of continuous Epo delivery by this method in normal rats and uremic five-sixths nephrectomized rats. In normal rats, Epo gene expression and sufficient erythropoiesis occurred with Epo gene transfer in a dose-dependent manner, and persisted for at least 11 weeks. Repeated administration of the plasmid DNA effectively produced erythropoiesis. Similar erythropoiesis was observed in the uremic rats, and persisted for more than 15 weeks. Both normal and uremic rats showed a significant decrease in platelet count. Moreover, the uremic rats showed Epo-induced hypertension, which is the major side-effect of recombinant human Epo. These results demonstrate that muscle-targeted pCAGGS-Epo transfer by in vivo electroporation is a useful procedure for the long-term continuous delivery of Epo in both normal and uremic rats.

Animals↗

PubMed2001

Skin-targeted gene transfer using in vivo electroporation.

The skin is an important target for gene transfer because of its easy accessibility. Using plasmid DNA expressing rat erythropoietin (pCAGGS-Epo) as the vector, we previously demonstrated long-term Epo delivery in rats by muscle-targeted gene transfer using in vivo electroporation. Here we examined whether this electroporation approach could be applied to gene delivery in rat skin. To optimize gene transfer, we tested the efficiency of skin-targeted Epo gene transfer with three types of electrodes at three different electrode voltages. Each rat was injected intradermally with a total of 800 microg of pCAGGS-Epo, in the abdominal area. Plate-and-fork-type electrodes were effective for Epo delivery by skin-targeted gene transfer at low voltages (12 approximately 24 V). The vector-derived Epo mRNA was expressed only at the DNA injection site. The Epo gene was expressed in a dose-dependent manner, the expression persisted for 7 weeks, and hematocrit levels were increased for 11 weeks. Skin injection with pCAGGS-lacZ showed lacZ gene expression in the epidermis on day 1 after injection and in the subcutaneous muscle layer on day 7. Slight skin damage due to the gene transfer procedure was evident on day 1, but absent by day 7. These results demonstrate that skin-targeted pCAGGS-Epo transfer by in vivo electroporation at low voltage is a useful procedure for the short-term delivery of Epo.

Animals↗

PubMed2001

Renal cell carcinoma with extension of tumor thrombus into the vena cava: surgical strategy and prognosis.

PURPOSE: The outcome of patients who underwent radical resection of renal cell carcinoma extending into the vena cava was retrospectively analyzed, and risk factors for long-term survival were investigated. METHODS: From 1983 to 1999, 33 patients who had renal cell carcinoma with inferior vena caval tumor extension underwent 34 surgical procedures. There were 27 men and six women with an average age of 60.1 years. Twenty-two cases (64.7%) were classified as stage III (T1-2 N1 M0 or T3 N0-1 M0), and 12 cases (35.3%) as stage IV (T4 or N2-3 or M1). Coexistent lung metastasis was found in seven cases (20.6%). The tumor thrombi invaded into the inferior vena cava below the hepatic hilum in 19 cases, below the orifice of hepatic veins in 12, and above the diaphragm in 3. Cardiopulmonary bypass graft was applied in 13 cases (38.2%). Inferior vena cava was reconstructed by direct suture (n = 19), polytetrafluoroethylene patch angioplasty (n = 13), or graft replacement (n = 2). RESULTS: Two patients died during the early postoperative period because of retrohepatic caval injury and intraoperative pulmonary embolism. Late death occurred in 16 patients; the causes of death were tumor recurrence in 15 and acute pulmonary embolism as a result of graft thrombosis in 1. Overall 1-, 5-, and 10-year survival rates were 70%, 44%, and 26.4%, respectively. One- and 5-year survival rates were 81.3% and 52.9% for stage III and 50% and 31.2% for stage IV; a statistically significant correlation was found between surgical staging and survival (P =.049). Patients without lymph node metastasis had a significant survival advantage over those with lymph node metastasis (P =.022). There was no significant difference in survival on the basis of the presence or absence of synchronous lung metastasis (P =.291). The degree of local extension of the tumor or the level of tumor thrombus did not tend to influence survival. CONCLUSIONS: Surgical prognosis in patients with renal cell carcinoma extending into the vena cava was determined by the staging of the tumor, especially lymph node status, and not by the level of tumor thrombus or the presence of concurrent lung metastasis. The use of cardiopulmonary bypass graft is recommended for the resection of tumor thrombus extending over the diaphragm.

Adult↗

PubMed2001

Coronary artery bypass grafting in a patient with brainstem ischemia.

We describe a 54-year-old male with severe coronary artery disease and cerebrovascular disease including right cerebellar infarction, total occlusion of the bilateral vertebral arteries, brainstem ischemia, and right cerebral infarction with significant right carotid artery disease. Repeated percutaneous transluminal coronary angioplasty had been performed, however, unstable angina was developed despite maximal medical treatment. Coronary artery bypass grafting was successfully undergone with use of propofol, application of the intra-aortic balloon pumping perioperatively, and mild hypothermic cardiopulmonary bypass with alpha-stat blood gas management. The importance of preoperative evaluation of the intracranial circulation and management of cardiopulmonary bypass are discussed.

Angina, Unstable↗

PubMed2000

Continuous erythropoietin delivery by muscle-targeted gene transfer using in vivo electroporation.

It has been demonstrated that gene transfer by in vivo electroporation of mouse muscle increases the level of gene expression by more than 100-fold over simple plasmid DNA injection. We tested continuous rat erythropoietin (Epo) delivery by this method in normal rats, using plasmid DNA expressing rat Epo (pCAGGS-Epo) as the vector. A pair of electrodes was inserted into the thigh muscles of rat hind limbs and 100 microg of pCAGGS-Epo was injected between the electrodes. Eight 100-V, 50-msec electric pulses were delivered through the electrodes. Each rat was injected with a total of 400 microg of pCAGGS-Epo, which was delivered to the medial and lateral sides of each thigh. The presence of vector-derived Epo mRNA at the DNA injection site was confirmed by RT-PCR. The serum Epo levels peaked at 122.2 +/- 33.0 mU/ml on day 7 and gradually decreased to 35.9 +/- 18.2 mU/ml on day 32. The hematocrit levels increased continuously, from the preinjection level of 49.5 +/- 1.1 to 67.8 +/- 2.2% on day 32 (p < 0.001). In pCAGGS-Epo treated rats, endogenous Epo secretion was downregulated on day 32. In a control experiment, intramuscular injection of pCAGGS-Epo without subsequent electroporation did not significantly enhance the serum Epo levels. These results demonstrate that muscle-targeted pCAGGS-Epo transfer by in vivo electroporation is a useful procedure for the continuous delivery of Epo.

Animals↗

PubMed2000

Endoluminal laser application under percutaneous cardiopulmonary support in severe tracheal stenosis.

Laser ablation under bronchoscopic guidance was conducted on 2 patients with severe tracheal stenosis. Case 1 was a 57-year-old man admitted to our emergency unit because asphyxia. Bronchoscopy showed the lumen occluded at the bifurcation by tracheal cancer. Case 2 was a 62-year-old woman who underwent tracheostomy elsewhere for respiratory failure caused by a brain contusion and was treated for 3 months. After transfer to our emergency unit, bronchoscopy showed severe tracheal stenosis. Tracheoplasty conducted under bronchoscopy used a noncontact Nd:YAG laser at an output of 10-40 W and irradiation time of 1 second per shot. Total irradiation energy was 1700-1900 J. Percutaneous cardiopulmonary support was used during the laser procedure due to asphyxia. All procedures were completed satisfactorily and clinical symptoms improved dramatically in both cases. Laser tracheoplasty under bronchoscopic guidance treated severe stenosis safely and completely. Percutaneous cardiopulmonary support was very useful in preventing severe respiratory failure or asphyxia during this procedure.

Asphyxia↗

PubMed2000

Management of cholelithiasis in combination with cardiovascular surgery.

A retrospective review of the perioperative management of patients with cardiovascular surgical disorders and cholelithiasis was conducted, and the surgical strategies employed are discussed. Between 1988 and 1998, 18 patients having cardiovascular surgical disorders underwent cholecystectomy. These patients were divided into three groups: group I, given a one-stage operation (n = 9); group II, given a two-stage operation (n = 3); and group III, given cholecystectomy during follow-up after cardiovascular surgery (n = 6). In group I, a median laparotomy was adopted for patients with an abdominal aortic aneurysm (AAA) to allow both disorders to be treated through the same incision, whereas a right subcostal approach was employed to separate the incisions for patients who underwent cardiac operations. In group II, one patient underwent cholecystectomy before cardiac surgery, and two patients underwent cholecystectomy for postoperative cholecystitis after cardiovascular operations. One patient from group II and all from group III were on preoperative anticoagulant therapy, two of whom underwent laparoscopic cholecystectomy. No fatal complications such as prosthetic infection, intraperitoneal hemorrhage, or cerebral attack were encountered. In conclusion, we consider that performing cholecystectomy during AAA repair may be safe and prevents the risk of postoperative cholecystitis; it is preferable to treat cholelithiasis coexisting with cardiac disorders concomitantly with or before cardiac operations; and laparoscopic cholecystectomy can be safely performed under anticoagulant therapy.

Adult↗

PubMed2000

Papillary fibroelastoma of the left atrial appendage: echocardiographic findings.

Papillary fibroelastoma is a small and rare benign intracardiac tumor that most frequently arises from the valvular endocardium. We report a patient with acute myocardial infarction in whom a papillary fibroelastoma in the left atrial appendage was detected by a transesophageal echocardiography during evaluation of the myocardial infarction. The roles of transesophageal echocardiography and surgical intervention are discussed.

Angioplasty, Balloon, Coronary↗

PubMed2000

Intravenous leiomyomatosis extending into the right ventricular cavity: one-stage radical operation using cardiopulmonary bypass--a case report.

The authors describe a 47-year-old woman with intravenous leiomyomatosis (IVL) extending into the right ventricular cavity. This rare entity is a neoplasm originating from smooth muscle of the uterus, with vermiform extensions into the inferior vena cava. The patient underwent a one-stage operation under simultaneous sternotomy and laparotomy, and radical excision of the tumor was successfully achieved with use of normothermic cardiopulmonary bypass. Although this tumor is histologically benign, it sometimes extends into the cardiac cavity and causes sudden death due to incarceration into the atrioventricular orifice. Moreover, recurrence or lung metastasis of IVL has been reported. The authors recommend a one stage-radical resection of the tumor or a two-staged operation within a short interval. In the literature, 24 surgical cases of the intravenous leiomyomatosis with intracardiac extension have been reported. The diagnosis and surgical treatment of this tumor are reviewed and discussed.

Cardiac Surgical Procedures↗

PubMed2000

Malignant peritoneal mesothelioma associated with deep vein thrombosis following radiotherapy for seminoma of the testis.

A 52-year-old man developed malignant peritoneal mesothelioma 17 years after radiotherapy for seminoma of the testis. Although asbestos exposure is considered to be the major risk factor for the development of malignant mesothelioma, prior therapeutic radiation has also been postulated as a causative factor. The unexplained appearance of ascites or pleural effusion within a previously irradiated area should be considered suggestive of malignant mesothelioma in any long-term survivor of cancer. In addition, the patient suffered a deep vein thrombosis four years before the diagnosis of mesothelioma. Deep vein thrombosis is a common complication of malignant disease, and is often the first clue to occult malignancy.

Humans↗

PubMed1999

Laparoscopic adrenalectomy for solitary metachronous adrenal metastasis from lung cancer: report of a case.

We report herein the case of a 69-year-old man who underwent laparoscopic adrenalectomy for a solitary adrenal metastasis 10 months after a left lower lobectomy for T2N1M0 lung cancer. A 30 x 20 mm tumor was found in the left adrenal gland, and dissected using an ultrasonically activated scalpel. Histological examination revealed metastatic squamous cell carcinoma. The patient recovered uneventfully and his condition is now stable 18 months after the second operation, with no evidence of local recurrence or metastatic disease. Although laparoscopic resection for malignant adrenal tumors is still controversial, we consider that laparoscopic adrenalectomy may be an optional treatment for metastatic adrenal tumors, provided the tumor is solitary, small in size, and well-localized. To our knowledge, only 14 cases of laparoscopic adrenalectomy for malignant tumors have been reported to date; however, this is the first case of successful laparoscopic adrenalectomy for a metastasis from lung cancer.

Adrenal Gland Neoplasms↗

PubMed1999

Mild hypothermia for temporary brain ischemia during cardiopulmonary support systems: report of three cases.

Recovery without residual neurological damage after cardiac arrest with temporary cerebral ischemia is rare. Therefore, it is most important that every effort is made to prevent brain damage occurring immediately after successful cardiopulmonary resuscitation. We report herein the cases of three patients who suffered either cardiogenic or hypovolemic shock and were resuscitated by a cardiopulmonary support system followed by mild hypothermia. All three patients recovered completely without any neurologic damage. The outcomes of these three patients demonstrated that mild hypothermia may be important for cerebral preservation after cardiopulmonary resuscitation.

Aged↗

PubMed1999

Transabdominal inguinal hernioplasty combined with abdominal aortic aneurysm repair.

The number of patients being encountered with abdominal aortic aneurysm (AAA) and inguinal hernia is increasing. We describe herein a technique of performing a concomitant one-stage operation for both disorder. After conventional transperitoneal AAA repair, transabdominal preperitoneal hernia repair is carried out through the same incision using a prosthesis made from the same material as the graft used for AAA. The maneuver is similar to that of laparoscopic hernioplasty. We employed this technique in the treatment of four patients, none of whom developed any complications such as infection or recurrence of the inguinal hernia. Thus, we conclude that this one-stage operation for AAA and inguinal hernia may bring physical and economic benefits to patients who have both diseases concomitantly.

Aged↗

PubMed1999

Valvular heart disease. A comparative study of results after primary operation, reoperation, and after multiple reoperation.

Reoperation for valvular heart disease has been associated with a higher operative mortality than primary operations, especially in patients who had multiple prior operations. We have analyzed the 226 consecutive patients who underwent valve replacement. These involved 163 primary operations, 52 first reoperation, and 11 second/third reoperations. Preoperative left ventricular dysfunction was more severe, and operation time and cardiopulmonary bypass time were significantly greater according to the number of operations, associated with a greater amount of intraoperative blood loss. The operative mortality after a second/third reoperation was 27.3%, which was significantly higher than that after primary operation (6.7%) (p < 0.05), and that after first reoperation (5.8%) (p < 0.05). Seven (64%) patients who underwent a second/third reoperation had poor preoperative left ventricular function (%FS < 25%), and 5 (71%) of these required postoperative mechanical supports, and 3 (60%) of the 5 patients died of low output syndrome. We have found that poor preoperative left ventricular function and the duration on cardiopulmonary bypass, but not the number of reoperation were correlated with operative mortality. Continued efforts should be directed to decrease the mortality for multiple reoperative valve surgery.

Adult↗

PubMed1999

Intraabdominal nonvascular operations combined with abdominal aortic aneurysm repair.

The therapeutic approach to a patient who has an abdominal aortic aneurysm (AAA) and an intraabdominal nonvascular surgical disorder simultaneously remains controversial. To establish guidelines for the management of those patients, a retrospective review of patients who had concomitant AAA and intraabdominal nonvascular surgical disorders was undertaken. During the period January 1988 to December 1997 a series of 162 patients underwent surgical repairs of AAA in our hospital. Among them 16 patients (9.9%) had several kinds of intraabdominal nonvascular surgical disorders, and 13 underwent one-stage operation for both diseases. That is, cholelithiasis coexisted in five patients, inguinal hernia in four, gastric cancer in two, and retroperitoneal tumor and renal tumor in one each. All AAAs were the infrarenal type, and there were no inflammatory or ruptured aneurysms. In cases of cholelithiasis coexistent with AAA, aneurysmectomy was performed first. After tight closure of the retroperitoneum, cholecystectomy was done. In cases of cholelithiasis coexistent with AAA, aneurysmectomy was performed first. After tight closure of the retroperitoneum, cholecystectomy was done. In cases of inguinal hernia coexistent with AAA, the AAA was first replaced with a prosthetic vascular graft and a residual piece of the graft was used as a patch for hernioplasty. This procedure was similar to laparoscopic hernioplasty. In two cases of gastric cancer concomitant with AAA, the AAA was first replaced. Subtotal gastrectomy with D2 lymphatic dissection was done after tight closure of the retroperitoneum. A drain was inserted into the epiploic foramen to detect anastomotic leakage. A retroperitoneal tumor coexisting with AAA was dissected and resected en bloc with the aneurysmal wall because the tumor firmly adhered to the aneurysm. The abdominal aorta was then replaced with a prosthetic graft. In a case of renal tumor concomitant with AAA, nephrectomy was done first to perform a complete lymphatic dissection around the renal artery. Then AAA repair was performed with a conventional procedure. There were no fatal complications, such as pneumonitis, hemorrhage, anastomotic leakage, or graft infection. All 13 patients were discharged from our hospital and are currently free from recurrence of malignancy or hernia. In summary, properly selected one-stage operations for intraabdominal nonvascular surgical disorders and AAA may be safe and bring physical and economic benefit to the patient.

Aged↗