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K Gan

Publications and source records attributed to K Gan.

35 records · Page 2Linked to original sources
PubMed1995

One-stage primary repair of distal esophageal perforation using fundic wrap.

Esophageal leak following primary repair of esophageal perforation is a serious complication that can lead to severe mediastinitis and sepsis. Complete diversion with esophageal exclusion or resection is designed to minimize further mediastinal contamination. However, this approach is not necessarily associated with less morbidity or mortality. Furthermore, a second stage operation is required to restore esophageal continuity. From 1986 to 1994, we performed a one-stage primary repair of the distal esophagus in seven patients with either iatrogenic (n = 5) or spontaneous (n = 2) perforations and reinforced the repair by a fundic wrap. One patient underwent an additional modified Heller myotomy for achalasia. Delay between perforation and operation was less than 6 hours in 3 patients, 6 to 24 hours in 2 patients, and greater than 24 hours in 2 patients. Only one patient (14%) developed a small esophageal leak that spontaneously resolved with adequate mediastinal drainage, intravenous antibiotics, and aggressive nutritional support. One patient (14%), whose repair was delayed by 12 hours, died postoperatively of profound sepsis. This patient was moribund from sepsis preoperatively, and postmortem examination of the esophagus revealed no evidence of esophageal leak. Esophageal continuity was maintained in all patients. The median length of stay was 21 days (range, 15-58 days). We conclude that primary reinforced repair of esophageal perforation using a fundic wrap is an effective method of treatment for distal esophageal perforation, even when the repair is delayed by more than 24 hours.

Adult↗
PubMed1995

[A comparison of changes of cerebrovascular oxygen saturation in retrograde and selective cerebral perfusion during aortic arch surgery].

To evaluate the effect of retrograde cerebral perfusion (RCP) and selective cerebral perfusion (SCP) on brain protection, changes of cerebrovascular oxygen saturation (rSO2) were studied in 14 patients with aortic arch reconstruction during the procedure. The rSO2 was monitored with spectroscopy instrument (Invos 3100, Somanetics). The mean value of rSO2 measured just before cardiopulmonary bypass was 65.9 +/- 6.2% in 7 patients with RCP, and was 64.9 +/- 4.7% in 7 patients with SCP. The value of rSO2 during core cooling of cardiopulmonary bypass was increased step by step. Although RCP time with a mean of 38.9 +/- 9.7 min was statistically shorter than SCP time (80.7 +/- 45.1 min), the mean value of rSO2 during cerebral protection in RCP group was decreased from 80.3 +/- 8.1% to 63.4 +/- 10.2%, lowest 46% with a ratio of 21.1%. In contrast, the mean value of rSO2 in SCP group was well maintained from 79.9 +/- 6.5 to 75.6 +/- 6.8%, lowest 63% with a ratio of 5.4%. Although no neurological deficits were recognized after operation in both groups, rSO2 in SCP group was sustained above the control value (65% just before cardiopulmonary bypass) but rSO2 in RCP group was decreased below the control value after 35 min. So we conclude that with regard to brain protection assessed from rSO2 measured by Invos 3100 cerebral oximeter, there is no time limitation of SCP during the procedure but RCP had a limit of the duration.

Aged↗
PubMed1994

Tidal ventilation at low airway pressures can augment lung injury.

Intermittent positive pressure ventilation with large tidal volumes and high peak airway pressures can result in pulmonary barotrauma. In the present study, we examined the hypothesis that ventilation at very low lung volumes can also worsen lung injury by repeated opening and closing of airway and alveolar duct units as ventilation occurs from below to above the infection point (Pinf) as determined from the inspiratory pressure-volume curve. We ventilated isolated, nonperfused, lavaged rat lungs with physiologic tidal volumes (5 to 6 ml/kg) at different end-expiratory pressures (above and below Pinf) and studied the effect on compliance and lung injury. In the groups ventilated with positive end-expiratory pressure (PEEP) below Pinf compliance fell dramatically after ventilation. It did not change in either the control group or the group ventilated with PEEP above Pinf. Lung injury assessed morphologically was significantly greater in the groups ventilated with a PEEP below Pinf, and in these groups the site of injury was dependent on the level of PEEP. The group ventilated without PEEP had significantly greater respiratory and membranous injury to bronchioles, while the group ventilated with PEEP of 4 cm H2O had significantly greater alveolar duct injury. In conclusion, ventilation at lung volumes below those found at Pinf caused a significant decrease in lung compliance and progression of lung injury. Therefore, in addition to high airway pressures, end-expiratory lung volume is an important determinant of the degree and site of lung injury during positive-pressure ventilation.

Animals↗
PubMed1993

Isolation and characterization of a temperature-sensitive mutant of Salmonella typhimurium defective in prolipoprotein modification.

A temperature-sensitive (ts) mutant of Salmonella typhimurium that accumulated unmodified murein prolipoprotein at 42 degrees C but not at 30 degrees C was identified. In vivo and in vitro studies of the biosynthesis of Braun's lipoprotein revealed that this mutant (SE5221) was defective in the glyceryl modification of prolipoprotein. The ts mutation was mapped to 60.6 min of the S. typhimurium chromosome and was linked to argA and cysH. A clone with a 1.4-kilobase S. typhimurium DNA insert that complemented the ts mutation and restored the prolipoprotein modification activity both in vivo and in vitro was isolated. DNA sequencing of the complementing region revealed an open reading frame encoding a protein with 291 amino acids lacking NH2-terminal signal sequence. This open reading frame is immediately 5' to the thyA gene and is allelic to umpA of Escherichia coli. Wild-type strains harboring the cloned gene exhibited elevated levels of prolipoprotein modification activity. At the non-permissive temperature, the mutation affected both growth and viability, and the mutant cells exhibited anomalous cell morphology. The ts phenotype was suppressed by the introduction of a lpp::Tn10 mutation. These results suggest that the cloned gene encodes prolipoprotein glyceryl transferase (lgt), and in the wild-type background, this prolipoprotein modification enzyme is essential for the growth and viability of S. typhimurium.

Alleles↗
PubMed1993

Characterization of a temperature-sensitive mutant of Salmonella typhimurium defective in apolipoprotein N-acyltransferase.

On screening 440 temperature-sensitive (ts) mutants of Salmonella typhimurium, a mutant strain SE5312 which accumulated apolipoprotein (ALP) at 42 degrees C was identified. In vitro assay of apolipoprotein N-acyltransferase activity indicated that the mutant cell envelope contained reduced activity as compared to the wild-type strain. Transduction with a Mud-P22 mapping set placed the ts mutation to 14-17 min region of the S. typhimurium chromosome. P22 transduction using transposon insertions in this region revealed a linkage of the ts mutation to cobD (6%), nag (8%), and corC68 (99%). The ts phenotype was complemented by a 2.3-kilobase EcoRI subclone derived from lambda-phage 170 of Kohara's bank of Escherichia coli. Restriction enzyme analysis of the cloned DNA revealed that this 2.3-kilobase EcoRI fragment included the copper transport (cutE) gene in E. coli. The mutant strain SE5312 was copper-sensitive at 30 degrees C, and the complementing clone conferred copper resistance and restored the ALP N-acyltransferase activity in the mutant cell. Wild-type strain of S. typhimurium harboring this clone exhibited elevated levels of ALP N-acyltransferase activity. These results suggest that the cloned gene encodes the ALP N-acyltransferase. Upon shift to the non-permissive temperature, the viability of the mutant cells decreased, and the mutant cells assumed anomalous morphology. Temperature-resistant revertants could be readily isolated, and a subset of tr revertants contained no detectable lipoprotein. A lpp::Tn10 derivative of the mutant SE5312 was also temperature-resistant. These observations suggest that ALP N-acyltransferase is essential for the growth and viability of S. typhimurium, and this requirement is decreased in the absence of major outer membrane lipoprotein.

Acylation↗
PubMed1993

On-line determination of pulmonary blood flow using respiratory inert gas analysis.

An inert gas analysis method has been developed to perform on-line real time determination of pulmonary blood flow using a nonrebreathing approach. This technique is based on a mathematical model describing mass balance of two inert gases which are breathed using an open gas circuit. The measurements using this method are noninvasive, easy to peform, and do not disturb normal physiological processes. As well, since data are collected on a breath-by-breath basis, it is possible to estimate other respiratory, cardiopulmonary, and metabolic parameters simultaneously in a breath-by-breath manner. Special consideration was given to developing effective data processing algorithms to minimize the influence of measurement noise and respiratory variations. Experimental studies to compare this method with other accepted techniques were conducted to validate the present technique.

Acetylene↗
PubMed1993

[A case of left atrial ball thrombus].

A 76-year-old man admitted to one hospital complaining of transient left hemiparesis. Because of arrhythmia, he was examined by an echocardiogram and found to have an oval free-floating thrombus in his left atrium concomitant with mitral stenosis. He was transferred to our hospital for emergency surgery. On operation, a 3 x 4 cm ball thrombus was removed and diseased mitral valve was replaced with a SJM prosthetic valve. His postoperative course was relatively uneventful. Though left atrial ball thrombus is rarely found among the patients with mitral valve disease, when left atrial ball thrombus is found, immediate surgical intervention is recommended to avoid sudden death.

Heart Atria↗
PubMed1993

[A successful VA bypass treatment in patient with severe pulmonary hypertension].

Report of a case of a patient with pulmonary hypertension associated with pericardial effusion who was treated by VA bypass during life-threatening right ventricular failure. A 63-year-old man was admitted to our hospital complaining of chest pain and dyspnea. Echocardiography revealed the patient had severe pulmonary hypertension and pericardial effusion. Though there were deep Q waves in ECG, his coronary angiography revealed normal coronary arteries. Pulmonary scintigraphy showed no evidence of pulmonary thromboembolism. As he developed hypotension and anuria, emergency pericardial drainage was carried out without any beneficial effect. Because no effective drugs were found to control his systemic hypotension and pulmonary hypertension, he was treated by VA bypass to save his life. Although his systemic pressure rose to normal level following institution of VA bypass, his pulmonary pressure remained high constantly, around 60-70mmHg. The VA bypass was discontinued on the 6th day because of bleeding tendency. 3 months after VA bypass, though he had not been given any drugs to control pulmonary hypertension, his pulmonary arterial pressure dropped down to within normal range. Though the exact mechanism or etiology of pulmonary hypertension remained unclear, this may be a rare case treated by VA bypass successfully for life-threatening right ventricular failure caused by pulmonary hypertension.

Extracorporeal Membrane Oxygenation↗
PubMed1992

[A successful case of tricuspid valvulectomy for Ebstein's anomaly with severe tricuspid stenosis].

A 44-year-old male was admitted to our hospital complaining of general fatigue and dyspnea on exertion with congestive heart failure (NYHA IV). Cardiac catheterization and angiogram revealed Ebstein's anomaly with severe tricuspid stenosis and functioning small right ventricle. Because of tiny right ventricular chamber, the usual surgical treatment for Ebstein's anomaly i.e. tricuspid valve replacement or valvuloplasty were deemed to be inappropriate. Tricuspid valvulectomy was performed to relieve the inflow stenosis of the right ventricle and excellent symptomatic relief was achieved. It is very rare to seen an adult case of Ebstein's anomaly with severe tricuspid stenosis and functioning small right ventricle. Tricuspid valvulectomy may be justified to use in this rare condition.

Adult↗
PubMed1990

Murine monoclonal antibodies to human pancreatic cancer: specificity and sensitivity.

Pancreatic carcinoma (n = 7), pancreatitis tissue (n = 4), normal pancreas tissue (n = 5), colonic adenocarcinoma (n = 4) and in vitro human pancreatic cancer cell lines (n = 6) were studied with the murine monoclonal antibodies (MAbs) 3DS2A, AR1-28, AR2-20, Ca19-9 and CA17-1A to determine their immunohistologic specificity and sensitivity for use as radiolabeled diagnostic imaging agents. Using the avidinbiotin-immunoperoxidase staining technique, MAbs 3DS2A and AR1-28 stained 86 and 100% of pancreatic cancer specimens, respectively. MAbs 3DS2A and AR1-28 are suitable agents for use as radiolabeled diagnostic imaging agents in patients with pancreatic cancer.

Adenocarcinoma↗
PubMed1990

[A case of pulmonary paraganglioma].

A pulmonary paraganglioma that was discovered incidentally as a solitary coin lesion on abdominal CT was successfully resected. Though this type of paraganglioma is extremely rare, it needs to be differentiated from certain other pulmonary neoplasms.

Aged↗
PubMed1989

A case of postnephrectomy arteriovenous fistula.

A rare case of a postnephrectomy arteriovenous fistula involving the major renal vessels is presented herein. This type of postnephrectomy arteriovenous fistula is very unusual; in fact, since first documented in 1934, only 65 cases have been reported in the world literature, including 2 cases from Japan. Even though postoperative arteriovenous fistulae are rare, one should bear this complication in mind when unknown causes of bruit or heart failure develop following surgery.

Aorta, Abdominal↗
PubMed1989

[Thoracoabdominal ectopia cordis with single ventricle and pulmonary stenosis. A case report of successful surgical repair].

A case of thoracoabdominal ectopia cordis with single ventricle and pulmonary stenosis is reported. A cyanotic boy with omphalocele was brought to our hospital soon after his birth and was diagnosed as thoracoabdominal ectopia cordis with single ventricle and pulmonary stenosis. A conservative treatment of omphalocele was performed successfully and a plastic chest shield had been made for him which protected the anterior surface of his chest. He continued to develop in a fairly satisfactory condition and operation was delayed until he was 8 years old when he had severe cyanosis and frequent episodes of headache. The operative procedures were; 1) ascending aorta to main pulmonary artery shunt with EPTFE tube; 2) to bring the heart into the thoracic and abdominal cavity by developing widely the pericardial and diaphragmatic defect behind the heart's preoperative position; 3) to reconstruct the new pericardial sac lying from thoracic to abdominal cavity by covering the heart using EPTFE sheet. This trial of making a new pericardial sac for thoracoabdominal ectopia cordis is not reported so far in the literature. It is expected that the heart has being raised to the thoracic cavity with patient's physical growth after this operation.

Child↗
PubMed1984

[Advantages and limits on the surgical therapy of esophageal cancer].

During a 11-year period, 315 patients of squamous cell carcinoma of the thoracic esophagus were treated. Notwithstanding the great majority of the patients had advanced cancer and operative contra-indications were very limited, the percentage of the operation of total patients was 94% (297/315) and that of operative mortality was 7.0% (20/297). As a standard surgical procedure, subtotal esophagectomies were performed through a right thoracotomy, followed by a laparotomy with simultaneous reconstruction via the posterior mediastinal route. On the 181 cases of the squamous cell carcinoma of the thoracic esophagus resected and reconstructed by this method before 1977, the survival rate of 1-year was 50%, that of 3-years was 19% and that of 5-years was 10%. Post operative T-shaped irradiation was performed in about a half of the total 181 patients. The efficacy of the postoperative irradiation was discernible in patients of each stage. It is expected that a precise schedule of chemotherapy and immunotherapy combined with post-operative irradiation might improve the prognosis of the esophageal cancer.

Adult↗