Heterogeneity of management practices surrounding operable gallbladder cancer - results of the OMEGA-S international HPB surgical survey

BACKGROUND

Gallbladder cancer (GBC) is an aggressive, uncommon malignancy, with variation in operative approaches adopted across centres and few large-scale studies to guide practice. We aimed to identify the extent of heterogeneity in GBC internationally to better inform the need for future multicentre studies.

METHODS

A 34-question online survey was disseminated to members of the European-African Hepatopancreatobiliary Association (EAHPBA), American Hepatopancreatobiliary Association (AHPBA) and Asia-Pacific Hepatopancreatobiliary Association (A-PHPBA) regarding practices around diagnostic workup, operative approach, utilization of neoadjuvant and adjuvant therapies and surveillance strategies.

RESULTS

Two hundred and three surgeons responded from 51 countries. High liver resection volume units (>50 resections/year) organised HPB multidisciplinary team discussion of GBCs more commonly than those with low volumes (p < 0.0001). Management practices exhibited areas of heterogeneity, particularly around operative extent. Contrary to consensus guidelines, anatomical liver resections were favoured over non-anatomical resections for T3 tumours and above, lymphadenectomy extent was lower than recommended, and a minority of respondents still routinely excised the common bile duct or port sites.

CONCLUSION

Our findings suggest some similarities in the management of GBC internationally, but also specific areas of practice which differed from published guidelines. Transcontinental collaborative studies on GBC are necessary to establish evidence-based practice to minimise variation and optimise outcomes.

Ral GTPase Activation by Downregulation of RalGAP Enhances Oral Squamous Cell Carcinoma Progression

Ral small GTPases, consisting of RalA and RalB, are members of the Ras family. Their activity is upregulated by RalGEFs. Since several RalGEFs are downstream effectors of Ras, Ral is activated by the oncogenic mutant Ras. Ral is negatively regulated by RalGAP complexes that consist of a catalytic α1 or α2 subunit and its common partner β subunit and similarly regulate the activity of RalA as well as RalB in vitro. Ral plays an important role in the formation and progression of pancreatic and lung cancers. However, the involvement of Ral in oral squamous cell carcinoma (OSCC) is unclear. In this study, we investigated OSCC by focusing on Ral. OSCC cell lines with high Ral activation exhibited higher motility. We showed that knockdown of RalGAPβ increased the activation level of RalA and promoted the migration and invasion of HSC-2 OSCC cells in vitro. In contrast, overexpression of wild-type RalGAPα2 in TSU OSCC cells attenuated the activation level of RalA and inhibited cell migration and invasion. Real-time quantitative polymerase chain reaction analysis of samples from patients with OSCC showed that RalGAPα2 was downregulated in oral cancer tissues as compared with normal epithelia. Among patients with OSCC, those with a lower expression of RalGAPα2 showed a worse overall survival rate. A comparison of DNA methylation and histone modifications of the RalGAPα2 gene in OSCC cell lines suggested that crosstalk among DNA methylation, histone H4Ac, and H3K27me2 was involved in the downregulation of RalGAPα2. Thus, activation of Ral GTPase by downregulation of RalGAP expression via a potential epigenetic mechanism may enhance OSCC progression.

Abstract P2-01-19: Sphingosine-1-phosphate affects tumor-associated macrophages in breast cancer patients

Background: Tumor-associated macrophages (TAMs) are considered to be one of the key players in the tumor microenvironment, which regulates cancer invasion and metastases. TAMs can be divided into two phenotypes with opposite functions. While M1 macrophages are known to exert anti-tumor activity by promoting pro-inflammatory effects and immune responses such as intereukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), M2 macrophages influence an anti-inflammatory response, wound healing, and pro-tumorigenic properties. A bioactive lipid mediator, sphingosine-1-phosphate (S1P) has emerged as a key regulatory molecule in cancer progression. We previously demonstrated that S1P generated by sphingosine kinase 1 (SPHK1), is a crucial mediator of breast cancer-induced angiogenesis and lymphangiogenesis, and promotes its metastasis. In particular, we found that SPHK1 is highly expressed in HER2 negative breast cancer, and the patients who developed lymph node metastasis demonstrated significantly higher levels of S1P (J Surg Res 2016). Although we have previously reported the role of S1P in recruitment of TAMs in vivo (Cancer Res 2018), its relevance in patients is yet to be uncovered. Here, we test our hypothesis that S1P signaling affects TAMs in human patients with breast cancer.

Materials and Methods: The expression level of each enzyme-encoding gene involved in S1P production was evaluated by retrieving RNA sequencing and gene expression quantification data using the Genomics Data Commons (GDC) data portal of the The Cancer Genome Atlas cohort. Gene expression levels were derived using normalization methods provided in the DESeq2 package. We compared the difference in expression levels of tumor associated macrophage related genes, including CD68, CD163, IL-6, andTNF-α between SPHK1-high breast tissue, and SPHK1-low breast tissue in the group of HER2 negative or positive patients. Unpaired t-tests were performed to compare expression differences between SPHK1-high and SPHK1-low breast tissue. All tests were two-sided and P values &lt; 0.05 were considered statistically significant.

Results: CD68, pan-macrophage marker, is significantly increased in SPHK1-high breast cancer tissues both in HER2 negative and positive breast cancer patients (p=&lt;0.001, &lt;0.01). CD163 which is a scavenger receptor that is regarded as highly specific for M2 macrophages is significantly increased in SPHK1-high breast cancer tissues in HER2 negative breast cancer patients, but not in HER2 positive breast cancer patients (p=&lt;0.001, 0.2). IL-6, which characterize M1 phenotype is significantly increased in SPHK1-high breast cancer tissues both in HER2 negative and positive breast cancer patients (p=&lt;0.001, &lt;0.001). TNF-α, which also characterizes M1 phenotype, is significantly increased in SPHK1-high breast cancer tissues in HER2 negative breast cancer patients, but not in HER2 positive breast cancer patients (p=&lt;0.001, 0.05).

Conclusion: Our results suggest that S1P affects TAMs in breast cancer patients, which implicate the important roles of S1P in the complicated immune system related to tumor progression. Our results also indicate that S1P have a large role in HER2 negative breast cancer patients. Further investigations are needed to understand the underlying mechanisms.

Citation Format: Tsuchida J, Nagahashi M, Moro K, Ikarashi M, Koyama Y, Sakata J, Kobayashi T, Kameyama H, Qi Q, Yan L, Takabe K, Wakai T. Sphingosine-1-phosphate affects tumor-associated macrophages in breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-01-19.

Simultaneous spawning by female stream goby Rhinogobius sp. and the association with brood cannibalism by nesting males

A laboratory experiment was conducted by varying the undersurface area of nesting substratum and the number of females in an experimental tank to elucidate the determinants of the mating pattern in the stream goby, Rhinogobius sp. cross-band type. Males with larger nests tended to attract two or more females to their nest in a tank. Moreover, males spawned simultaneously with multiple females and entire brood cannibalism by males was rarely observed under a female-biased sex ratio. When males spawned with a single female with low fecundity, however, entire brood cannibalism occurred at a high frequency, suggesting that a male guarding a nest with fewer eggs consumes the brood. Therefore, spawning behaviour of females that leads to a large egg mass would decrease the risk of entire brood cannibalism. In this species, simultaneous spawning by multiple females in a nest serves as a female counter-measure against entire brood cannibalism. These results suggest that a conflict of interest between the sexes through brood cannibalism is a major determinant of simultaneous spawning.

Study of Immune Tolerance Cases in Adult Living Donor Liver Transplantation

BACKGROUND

Complete immune tolerance is the chief goal in organ transplantation. This study aimed to evaluate patients who successfully withdrew from immunosuppressive (IS) agents after living donor liver transplantation (LDLT).

MATERIALS AND METHODS

A retrospective review of all adult LDLT from July 1999 to March 2012 was conducted. In patients who acquired immune tolerance after LDLT, their background and the course of surgical procedures were evaluated.

RESULTS

Of a total of 101 adult LDLT patients, 8 patients were completely free of IS agents. Six of these patients (75%) were female, and the median age at the time of transplantation was 56 years (range, 31-66 years). The primary disease causing liver failure was type C liver cirrhosis (50%), fulminant hepatitis (25%), type B liver cirrhosis (12%), and alcoholic liver cirrhosis (12%). The median Child-Pugh score and MELD score were 13 points (range, 8-15 points) and 19 points (range, 10-18 points), respectively. The living related donor was the recipient's child (75%), sibling (12%), or parent (12%). ABO compatibility was identical in 62%, compatible in 25%, and incompatible in 12%.

CONCLUSIONS

In this study, we evaluated the adult patients who successfully withdrew from IS agents after LDLT. In most cases, it took more than 5 years to reduce IS agents. Because monitoring of the serum transaminase level is not adequate to detect chronic liver fibrosis in immune tolerance cases, further study is required to find appropriate protocols for reducing IS agent use after LDLT.

Successful Endoscopic Management of Acute Necrotic Pancreatitis and Walled Off Necrosis After Auxiliary Partial Orthotopic Living-Donor Liver Transplantation: A Case Report

Endoscopic management of acute necrotic pancreatitis and walled off necrosis is less invasive than surgical treatment and has become the 1st choice for treating pancreatic necrosis and abscess. We treated a case of acute necrotic pancreatitis and walled off necrosis after auxiliary partial orthotopic living-donor liver transplantation (APOLT). A 24-year-old woman was admitted to our university hospital for removal of the internal biliary stent, which had already been placed endoscopically for the treatment of biliary stricture after APOLT. She had been treated for acute liver failure by APOLT 10 years before. After we removed the internal stent with the use of an endoscopic retrograde approach, she presented with severe abdominal pain and a high fever. Her diagnosis was severe acute pancreatitis after endoscopic retrograde cholangiography (ERC). Her symptoms worsened, and she had multiple organ failure. She was transferred to the intensive care unit (ICU). Immunosuppression was discontinued because infection treatment was necessary and the native liver had already recovered sufficiently. After she had been treated for 19 days in the ICU, she recovered from her multiple organ failure. However, abdominal computerized tomography demonstrated the formation of pancreatic walled off necrosis and an abscess on the 20th day after ERC. We performed endoscopic ultrasonography-guided abscess drainage and repeated endoscopic necrosectomy. The walled off necrosis diminished gradually in size, and the symptoms disappeared. The patient was discharged on the 87th day after ERC. This is the 1st report of a case of acute necrotic pancreatitis and walled off necrosis that was successfully treated by endoscopic management after APOLT.

Six-Year Graft Survival After Partial Pancreas Heterotopic Auto-Transplantation: A Case Report

BACKGROUND

Long-term graft survival of partial pancreas auto-transplantation after total pancreatectomy has not been clarified. The clinical implications of repeat completion pancreatectomy for locally recurrent pancreatic carcinoma in the remnant pancreas after initial pancreatectomy also have not been clarified.

METHODS

We have previously reported a 61-year-old woman presenting with re-sectable carcinoma of the remnant pancreas at 3 years after undergoing a pylorus-preserving pancreaticoduodenectomy for invasive ductal carcinoma of the pancreas head. We also performed distal pancreas auto-transplantation with the use of a part of the resected pancreas to preserve endocrine function.

RESULTS

The patient was discharged at 20 days after surgery without any complications. She had been followed regularly in our outpatient clinic. She had been treated with S-1 as adjuvant chemotherapy; 72 months after the completion total pancreatectomy with distal partial pancreas auto-transplantation, the patient was alive without any evidence of the pancreatic carcinoma recurrence. The pancreas graft was still functioning with a blood glucose level of 112 mg/dL, HbA1C of 6.7%, and serum C-peptide of 1.2 ng/mL; and urinary C-peptide was 11.6 μg/d.

CONCLUSIONS

Our patient demonstrated that repeated pancreatectomies can provide a chance for survival after a locally recurrent pancreatic carcinoma if the disease is limited to the remnant pancreas. An additional partial pancreas auto-transplantation was successfully performed to preserve endocrine function. However, the indications for pancreas auto-transplantation should be decided carefully in the context of pancreatic carcinoma recurrence.

Laparoscope-assisted Hassab's operation for esophagogastric varices after living donor liver transplantation: a case report

This is the first successful report of a laparoscope-assisted Hassab's operation for esophagogastric varices after living donor liver transplantation (LDLT). A 35-year-old man underwent LDLT using a right lobe graft as an aid for primary sclerosing cholangitis (PSC) in 2005. Follow-up endoscopic and computed tomography (CT) examinations showed esophagogastric varices with splenomegaly in 2009 that increased (esophageal varices [EV]: locus superior [Ls], moderator enlarged, beady varices [F2], medium in number and intermediate between localized and circumferential red color signs [RC2]; gastric varices [GV]: extension from the cardiac orifice to the fornix [Lg-cf], moderator enlarged, beady varices [F2], absent red color signs [RC0]). A portal venous flow to the esophagogastric varices through a large left gastric vein was also confirmed. Preoperative Child-Pugh was grade B and score was 9. Because these esophagogastric varices had a high risk of variceal bleeding, we proceeded with a laparoscope-assisted Hassab's operation. Operative time was 464 minutes. Blood loss was 1660 mL. A graft liver biopsy was also performed and recurrence of PSC was confirmed histologically. It was suggested that portal hypertension and esophagogastric varices were caused by recurrence of PSC. Postoperative complications were massive ascites and enteritis. Both of them were treated successfully. This patient was discharged on postoperative day 43. Follow-up endoscopic study showed improvement in the esophagogastric varices (esophageal varices [EV]: locus superior [Ls], no varicose appearance [F0], absent red color signs [RC0], gastric varices [GV]: adjacent to the cardiac orifice [Lg-c], no varicose appearance [F0], absent red color signs [RC0]) at 6 months after the operation. We also confirmed the improvement of esophagogastric varices by serial examinations of CT.

Long-term outcomes after hepatectomy for recurrences after prior local ablation for hepatocellular carcinoma

AIMS

Intrahepatic recurrence is the most common manifestation of failure after local ablation therapy for hepatocellular carcinoma. The present study evaluates the safety and efficacy of partial hepatectomy for intrahepatic recurrence after prior local ablation.

METHODS

A retrospective analysis was conducted of 188 consecutive patients with hepatocellular carcinoma who underwent either partial hepatectomy for recurrence after prior local ablation (n=13) or partial hepatectomy as initial local treatment (n=175). The 13 patients with recurrence after prior local ablation were referred to our division after the resectable recurrences were considered to be resistant to non-surgical treatment modalities.

RESULTS

The incidences of postoperative morbidity and mortality were similar for patients with prior local ablation and patients without prior local ablation (p=0.75 and p=0.52, respectively). The overall survival rates after hepatectomy were comparable between patients with prior local ablation (median survival time of 86months; cumulative 5-year survival rate of 63%) and patients without prior local ablation (median survival time of 76months; cumulative 5-year survival rate of 54%; p=0.60). The disease-free survival rates after hepatectomy were significantly worse for patients with prior local ablation based on both univariate (p=0.01) and multivariate (relative risk, 2.73; p<0.01) analyses.

CONCLUSIONS

Hepatectomy can be performed safely and may be efficacious, in terms of overall survival, for selected patients with intrahepatic recurrence after prior local ablation for hepatocellular carcinoma. On the other hand, prior local ablation appears to increase the probability of failure after hepatectomy.

Preoperative predictors of vascular invasion in hepatocellular carcinoma

AIMS

Vascular invasion is an established adverse prognostic factor in hepatocellular carcinoma (HCC). The aim of the current study was to identify the preoperative predictors of vascular invasion in patients undergoing partial hepatectomy for HCC.

METHODS

A retrospective analysis of 227 consecutive patients who underwent partial hepatectomy for HCC was conducted. Vascular invasion was defined as gross or microscopic involvement of the vessels (portal vein or hepatic vein) within the peritumoral liver tissue.

RESULTS

Seventy-six (33%) patients had vascular invasion. Among the preoperative factors, only the tumour size (relative risk, 16.78; p<0.01) and the serum alpha-fetoprotein (AFP) level (relative risk, 3.57; p<0.01) independently predicted vascular invasion. As the tumour size increased, the incidence of vascular invasion increased: < or =2 cm, 3%; 2.1-3 cm, 20%; 3.1-5 cm, 38%; and > 5 cm, 65%. The incidence of vascular invasion was 32% in patients with serum AFP levels < or =1000 ng/mL, compared to 61% in patients with higher serum AFP levels (p<0.01). Patients with both tumours >5 cm and serum AFP levels >1000 ng/mL had an 82% incidence of vascular invasion.

CONCLUSIONS

The tumour size and serum AFP level, alone or in combination, are useful in predicting the presence or absence of vascular invasion before hepatectomy for HCC.

First Report of Pepper yellow leaf curl Indonesia virus in Ageratum conyzoides in Indonesia

Ageratum conyzoides L. plants affected with yellow vein disease were collected from Magelang, Bandung, and Purwokerto locations in Indonesia during 2001. A. conyzoides is a naturally occurring weed that is found in and around fields of cultivated pepper (Capsicum annuum L.) and tomato (Lycopersicon esculentum L.). It is frequently found with symptoms of yellow vein disease and the abundance of whiteflies on the affected plants suggested the possible involvement of a geminivirus. Total nucleic acids were extracted from nine samples collected from these locations of A. conyzoides-affected plants exhibiting yellow vein disease and amplified using PCR with geminivirus DNA-A-specific designed primers (virion-sense primer 5'-GAGCTCTTAGCCGCCTGAATGTTC-3'; complementary-sense primer 5'-GAGCTCGTCAGATGTTAAGACCTAC-3') (1). A PCR-amplified product of approximately 2.7 kbp was obtained from each sample. Five independent sequences were cloned and sequenced from each sample. Sequence analysis showed that five of nine samples were Ageratum yellow vein virus (one each from Bandung and Purwokerto and three from Magelang) and the remaining four samples (two samples each from Bandung and Purwokerto) were a strain of Pepper yellow leaf curl Indonesia virus (PepYLCIDV). Full-length DNA-A of PepYLCIDV from systemic A. coniziodes was amplified using PCR with additional primers designed at only one restriction site (BamHI) (5'-GGATCCGCTTGTTCATCCTTTTCCAG-3'/5'-GGATCCCACATCTTTGGTTAGTGGAGGGTG-3') and cloned. Three independent clones obtained were sequenced and analyzed. The sequence of a full-length DNA-A component was determined (2,760 bases, GenBank Accession No. AB267838). PCR using degenerate primers (DNABLC1: 5'-GTVAATGGRGTDCACTTCTG-3'; DNABLC2: 5'-RGTDCACTTCTGYARGATGC-3', DNABLV2: 5'-GAGTAGTAGTGBAKGTTGCA-3') of begomovirus DNA-B component (2), five independent clones were obtained and sequenced. Primers designed to amplify a full-length B component were constructed around a unique restriction site (BamHI) (5'-GGATCCCCTCATTCCTTTTGCGGAG-3'/5'-GGATCCACAGAGGAAAACTCGCAAGGC-3'). A PCR product was obtained from A. conyzoides samples and three independent clones were sequenced and analyzed. A full-length sequence of a begomovirus B component was determined (2,746 bases, GenBank Accession No. AB267839). Five open reading frames (ORF) were found in DNA-A and two in DNA-B. The DNA-A and DNA-B had a common region (CR) (74% nucleotide sequence identity) that comprised approximately 160 nucleotides. The DNA-A and DNA-B had an identical 31-base stem loop region in the CR. In addition, DNA-A and DNA-B had the highest nucleotide sequence identity (93%) with those of PepYLCIDV (GenBank Accession Nos. AB267834 and AB267835), suggesting it is a strain of PepYLCIDV, which is widely prevalent in Indonesia. To our knowledge, this is the first report of PepYLCIDV isolated from A. conyzoides plants affected with yellow vein disease. References: (1) R. W. Briddon and P. G. Markham. Mol. Biotechnol. 1:202, 1994. (2) S. K. Green et al. Plant Dis. 85:1286, 2001.

Number of positive lymph nodes independently affects long-term survival after resection in patients with ampullary carcinoma

AIM

The nodal status is an established prognostic factor in ampullary carcinoma. The aim of this study was to compare the prognostic power of the anatomic location of positive nodes with that of the number of positive nodes.

METHODS

Of 73 consecutive patients treated for ampullary carcinoma, 62 underwent pancreaticoduodenectomy with regional lymphadenectomy. A survival analysis of these 62 patients by nodal status was conducted retrospectively. A total of 1942 lymph nodes taken from the patients were examined histologically for metastasis. The location of positive regional nodes was classified into 4 categories, according to the Japanese staging system. The number of positive regional nodes was recorded for each patient. The median follow-up period was 124 months.

RESULTS

Nodal disease was found in 31 patients, of whom 23 had 1-3 positive regional nodes and 8 had >or=4 positive regional nodes. Univariate analysis revealed that both the location (p<0.0001) and the number (p<0.0001) of positive nodes were significant prognostic factors. Multivariate analysis revealed that the number of positive nodes was an independent prognostic factor (p=0.007), while the location failed to remain as an independent variable. The median survival time was 59 months with a 5-year survival rate of 48% in patients with 1-3 positive nodes, whereas all patients with >or=4 positive nodes died of the disease within 29 months of resection (p=0.0001).

CONCLUSION

The number, not the location, of positive regional lymph nodes independently affects long-term survival after resection in patients with ampullary carcinoma.

[Utility of the perfusion-assist for beating heart coronary artery bypass surgery]

During off-pump coronary artery bypass surgery, concern remains about the possible myocardial injury associated with the transient occlusion and stabilization of the target vessels. To try to minimize myocardial ischemia and achieve hemodynamic stability, we utilized a coronary perfusion catheter combined with the perfusion-assisted direct coronary artery bypass system that enables active and modified coronary perfusion of the target vessel throughout the duration of multiple grafting (modified PADCAB). In the series of 10 patients, perfusion of the target coronary systems averaged 2,072.8 +/- 649.7 ml over 92.9 +/- 26.1 minutes under a constant infusion pressure of 120 mmHg. Nitroglycerin (100 micrograms/l of flow) was delivered directly into the coronary arteries as an additive in all patients. Hemodynamic instability was notably absent in all cases, even in cases that required difficult anastomosis with a relatively long time for the anastomosis. There were no perioperative complications and no detectable myocardial damage (i.e., impairment of myocardial wall motion indicated by echocardiography findings or by > 0.25 ng/ml of troponin-T release compared to the preoperative level) in this series of patients.

[Penetrating cardiac and pulmonary injury by a nail-gun: report of a case]

A 64-year-old man underwent emergency operation for self-inflicted penetrating cardiac and pulmonary injury by a nail-gun. Chest films on admission showed 5 nails penetrating the thorax and one of these nails had reached into pericardium. Emergency surgery was performed by median sternotomy and the 5 nails in the chest wall were totally removed and the wound of right ventricle and lung were closed with direct mattress sutures without cardio-pulmonary bypass. Post operative course was uneventful and he was transferred to the psychiatric ward for the treatment of depression at post operative 7 days.

Extrapleural resection of lung metastasis in a patient with dense pleural adhesions using VATS

We report the case of a 78-year-old man with dense pleural adhesion who underwent a resection of a lung metastasis by video-assisted thoracic surgery (VATS) through an extrapleural approach. The approach for diagnosis and therapeutic wedge resection of a lung tumor by VATS is easier and safer than an intrapleural approach if the patient has dense pleural adhesions.

[A successful repair of intraoperative retrograde type A aortic dissection in a patient with aortic regurgitation and ascending aortic aneurysm]

The patient was a 67-year-old male with aortic regurgitation and ascending aortic aneurysm. We noticed the type A retrograde aortic dissection occurring from the cannulation site through the right femoral artery. We discontinued cardio-pulmonary bypass immediately, and established selective cerebral perfusion (SCP) eleven minutes after retrograde cerebral perfusion (RCP). We underwent simultaneous aortic valve replacement and ascending and arch graft replacement with an aid of SCP combined with RCP and systemic low flow perfusion. Postoperative course was satisfactory, although patient had a transient neurologic deficit. Intraoperative aortic dissection is a rare but potentially fatal complication. RCP may be a simple and useful method in emergency operation for intraoperative retrograde type A aortic dissection to avoid serious cerebral damage.

[One advice to the decision of graft size for ascending and total arch graft replacement (in a case of differential diameters in ascending aorta and descending aorta)]

We carried out the surgery of thoracic aortic aneurysm in fifty-eight patients from June 1994 to February 1999 (including aortic dissection in twenty-six patients). The mean size of grafts were 28.1 mm in ascending graft replacement, 25.8 mm in both ascending and arch graft replacement and 23.8 mm in descending graft replacement. The grafts for ascending aortic aneurysm were significantly larger than those for descending aortic aneurysm. In two of twenty-six patients undergoing both ascending and arch graft replacement, different size of grafts were used for ascending replacement and for arch replacement with satisfactory results in terms of bleeding from the anastomotic sites. Case 1; A 45-year-female with aortitis syndrome and aortic regurgitation due to annuloaorticectasia and thoracic aortic aneurysm underwent simultaneous aortic root replacement with composite graft (25 mm St. Jude Medical valve and 28 mm Hemashield graft) and total arch replacement (30 mm Hemashield graft with two side branches). Case 2; A 64-year-female was diagnosed as chronic type II dissecting aneurysm combined with acute type I aortic dissection. Ascending aorta was replaced with a 26 mm Hemashield graft, and the aortic arch was replaced with a 24 mm Hemashield graft with three side branches.

Primary pericardial mesothelioma presenting as constrictive pericarditis: a case report

Primary malignant pericardial mesothelioma is a rare tumor and the case reported here presented as constrictive pericarditis. The patient's symptoms progressed day by day despite treatment with digitalis, diuretics and catecholamines. Although a computed tomographic scan of the chest, echocardiography and pericardiocentesis were performed, a preoperative definitive diagnosis could not be obtained. Emergency pericardiectomy and partial resection of the tumor were carried out with the aid of a percutaneous cardiopulmonary supporting system, but the patient died of cardiac failure on postoperative day 3. The tumor appeared to be the biphasic type of diffuse malignant mesothelioma. The prognosis for pericardial mesothelioma is extremely poor due to its late presentation and difficulty in completely removing it surgically and, unfortunately, there still is not a radical therapy for this tumor.

Marked increase of guanylin secretion in response to salt loading in the rat small intestine

Guanylin and uroguanylin are intestinal peptides that stimulate guanylate cyclase C and cause chloride secretion. These peptides show topological instability due to two disulfide bonds. The disulfide bonds were reduced and S-carboxymethylated to cleave the bonds and obtain stable and sole derivatives. We established a new and reliable RIA system for the stable derivatives from both peptides. With the use of this system, the response of the peptides to salt loading of the rat small intestine was evaluated. The lumen of the small intestines of Sprague-Dawley rats was perfused in vivo with Krebs-Ringer solution containing different concentrations of salt or mannitol. Mature guanylin, proguanylin, and mature uroguanylin were found in the perfusate in the basal state. The highest salt loading (200 mM NaCl for 20 min) increased the guanylin secretion about threefold (1.9 +/- 0.2 vs. 5.4 +/- 0.5 pmol/min), with the effect lasting for 60 min. The uroguanylin secretion was less affected. Hyperosmolar mannitol also caused a significant but smaller increase of guanylin secretion. Increased guanylin could lead to increased salt and water secretion of the intestine; thus members of the guanylin family have potential roles in the regulation of water and salt metabolism in the small intestine.

Novel distribution of adrenomedullin-immunoreactive cells in human tissues

Adrenomedullin (AM) is a novel hypotensive and vasodilator peptide. We previously examined the localization of AM in human, rat, and porcine tissues using a polyclonal antibody against synthetic human AM[40-52]. We demonstrated that AM is widely distributed in the endocrine and neuroendocrine systems, but not in the heart, kidney, or blood vessels, although high levels of AM mRNA were detected in the latter tissues. In this study, we further investigated the distribution of AM by using two newly developed monoclonal antibodies against synthetic human AM peptides, [12-25] and [46-52]. AM immunoreactivity was observed in cardiac myocytes, vascular smooth muscle cells, endothelial cells, and renal distal and collecting tubules. In addition, AM-immunoreactive (IR) cells were found in mucosal and glandular epithelia of the digestive, respiratory, and reproductive systems, as well as the endocrine and neuroendocrine systems. These findings indicate that AM-IR cells are more widely distributed in human tissues and suggest that AM might play multiple biological roles in humans.

[Complete disruption of thoracic descending aorta without widening of the pseudoaneurysm]

A 41-year-old male was transported to our emergency room 25 minutes after blunt chest trauma. The chest X-ray film and CT scanning demonstrated left pulmonary atelectasis, hemothorax, and widening of mediastinum possibly due to hematoma. Hundred and fifty minutes after arrival to the hospital, we were rush to bring him to the operation theater suspecting serious injury of the thoracic organs in association with bleeding from left thoracic drainage tube without detection of the aortic rupture. The left standard thoracotomy disclosed no injury of the left lung, good continuity and no dilatation of the thoracic descending aorta. But visual blood flow observed through the adventitia of the aortic isthmus led us to the final diagnosis of the aortic rupture. After aortic clamping, the intima of the injured aorta was found to be completely disrupted for a length of 6 cm and was repaired with a vascular prosthesis under the partial cardiopulmonary bypass using a centrifugal pump. His postoperative course was uneventful. We reported a case of complete circumferential aortic rupture without widening of the pseudoaneurysm in the acute stage of the disease.

Effect of septal lesions on male song and aggression in the colonial zebra finch (Taeniopygia guttata) and the territorial field sparrow (Spizella pusilla)

The present investigation assessed the effect of lesions of the septum on male courtship and aggression in the territorial field sparrow (Spizella pusilla) and the colonial zebra finch (Taeniopygia guttata). In addition, pair-bonding and a variety of other social behaviors were examined in the zebra finch and dawn song (both the strictly agonistic song type and the multipurpose song type) was examined in the field sparrow. Zebra finches were tested in three phases both before and after receiving bilateral electrolytic lesions of the septum or sham surgery. These phases were: (1) competition tests in which a subject and a stimulus male were exposed to a female in an adjacent cage; (2) sexual behavior tests with a female; and (3) 10-day group cage tests in which subjects were in a mixed-sex environment. Aggressive behaviors (chases, threats, beak fences and pecks) were significantly reduced by septal lesions but not by sham surgery. Directed song (courtship) was significantly reduced in sexual behavior tests, with similar trends in other testing phases. Male field sparrows were tested 2 days pre-surgery and 2 days post-surgery in outdoor aviaries placed in their natural habitat. Tests consisted of dawn song observations and observations of courtship and aggression following introduction of a female to the subject's aviary, which was followed 10 min later by the introduction of another male (without removing the female). Septal lesions significantly facilitated both overt aggression (chases) and the number of simple (multi-purpose) songs. These results provide evidence that the septum participates in the regulation of male aggression and song in songbirds, and further suggest that variations in septal function may exist between territorial and colonial species.

[Clinical study of six thymic carcinomas including long-term survivors]

Six cases of thymic carcinoma (mean age 48.5 years old, one male and 5 females) were treated in our hospital from September 1990 to September 1998. The histological subtypes of thymic carcinoma were squamous cell in 4, undifferentiated in one, and small cell in one. All cases underwent midsternal thoracotomy, 4 had total resection of the tumor and 2 had exploratory thoracotomy due to tumor invasion of the aorta and the main pulmonary artery. Within 2 years after operation, 2 cases without radiation therapy were died of the carcinoma and one case was died of asthma. However, two cases of squamous cell carcinoma have been alive and disease free for 3 and 5 years since the operation followed by mediastinal irradiation. We think that radiation therapy is very effective to control the disease because one of them underwent only exploratory operation prior to irradiation. Another one case who survives 5 years after total resection of the tumor following irradiation revealed swelling of numerous mediastinal lymph nodes, pathologically consisted of non-caseating epithelioid cell granulomas without metastasis of carcinoma, at the time of operation. These lymph nodes were diagnosed as "sarcoid-like reaction" because there was no clinical evidence of generalized sarcoidosis. The "sarcoid-like reaction" may contribute to the 5-year survival of the patient because it is thought to be a local immune response against the cancer cells. A remaining patient, alive 6 months after total resection of the thymic small cell carcinoma following irradiation, received preoperatively three cycles of the intra-arterial administration using CBDCA via bilateral internal mammary arteries. This induction chemotherapy had no response of the tumor size, but it was considered to have a possibility of reducing the size of thymic carcinoma by the use of other agents (CDDP, VDS etc.) because the tumor was fed mainly by the highly developed internal mammary arteries.

Cell density of adrenomedullin-immunoreactive cells in the gastric endocrine cells decreases in antral atrophic gastritis

AIMS

Adrenomedullin (AM) is a novel hypotensive and vasorelaxing peptide recently isolated from human phaeochromocytoma tissue, and is widely distributed in various organs. In this study we examined the localization of AM-immunoreactive (IR) cells in the gastric mucosa and AM-IR cell density in antral atrophic gastritis.

METHODS AND RESULTS

Gastric mucosal tissues were taken from the gastric body and antral mucosa of 52 patients (27 men, 25 women; mean age 56.0 (range 20-86) years). Immunohistochemical analysis revealed that AM-IR cells were present in the pyloric glands, but not in the fundic glands, and that AM-IR cells were stained positively for chromogranin A and gastrin. The percentage of AM-IR cells vs chromogranin A- and gastrin-IR cells was 42 and 56%, respectively. The number of AM-IR cells decreased with the progression of severity of atrophic changes in the pyloric gland, and also of mononuclear cell infiltration. There was no correlation between the number of AM-IR cells and the degree of neutrophilic infiltration. Similar findings were also obtained for gastrin-IR cells.

CONCLUSION

AM-IR cells are present in the endocrine cells including gastrin-IR cells in the pyloric glands. These results suggest that AM may contribute to gastrin secretion in the pyloric glands.

Effect of septal lesions on male song and aggression in the colonial zebra finch (Taeniopygia guttata) and the territorial field sparrow (Spizella pusilla)

The present investigation assessed the effect of lesions of the septum on male courtship and aggression in the territorial field sparrow (Spizella pusilla) and the colonial zebra finch (Taeniopygia guttata). In addition, pair-bonding and a variety of other social behaviors were examined in the zebra finch and dawn song (both the strictly agonistic song type and the multipurpose song type) was examined in the field sparrow. Zebra finches were tested in three phases both before and after receiving bilateral electrolytic lesions of the septum or sham surgery. These phases were: (1) competition tests in which a subject and a stimulus male were exposed to a female in an adjacent cage; (2) sexual behavior tests with a female; and (3) 10-day group cage tests in which subjects were in a mixed-sex environment. Aggressive behaviors (chases, threats, beak fences and pecks) were significantly reduced by septal lesions but not by sham surgery. Directed song (courtship) was significantly reduced in sexual behavior tests, with similar trends in other testing phases. Male field sparrows were tested 2 days pre-surgery and 2 days post-surgery in outdoor aviaries placed in their natural habitat. Tests consisted of dawn song observations and observations of courtship and aggression following introduction of a female to the subject's aviary, which was followed 10 min later by the introduction of another male (without removing the female). Septal lesions significantly facilitated both overt aggression (chases) and the number of simple (multi-purpose) songs. These results provide evidence that the septum participates in the regulation of male aggression and song in songbirds, and further suggest that variations in septal function may exist between territorial and colonial species.

Adrenomedullin in the gastrointestinal tract. Distribution and gene expression in rat and augmented gastric adrenomedullin after fasting

The aim of this study was to investigate the regional distribution, molecular forms, and gene expression of adrenomedullin in the rat gastrointestinal tract and to examine physiological changes in gastric adrenomedullin after 24-h fasting. The tissue concentration was measured by radioimmunoassay. The molecular forms were analyzed by high performance liquid chromatography. mRNA levels were quantified by Northern blotting and cells positive for adrenomedullin immunoreactivity were localized by immunohistochemistry. A high concentration of adrenomedullin was found in stomach, cecum, and colon (450-520 fmol/g wet tissue). Adrenomedullin immunoreactivity was also detected in duodenum, jejunum, and ileum (200-250 fmol/g wet tissue). Transcripts of the adrenomedullin gene were widely expressed throughout the gastrointestinal tract. The major form of adrenomedullin immunoreactivity in stomach and colon corresponded precisely with authentic adrenomedullin peptide. Adrenomedullin immunoreactive cells were present in the gastrointestinal endocrine system. The concentration and mRNA level of gastric adrenomedullin after fasting were significantly increased compared with findings in controls. Adrenomedullin is ubiquitous in the gastrointestinal tract, and may be produced by endocrine cells. The results suggest that adrenomedullin, through its potent vasodilating activity, may play some role, in the stomach including the regulation of the mucosal blood flow.

Distribution and expression of adrenomedullin in human gastrointestinal tissue

Adrenomedullin (AM) is a biologically active peptide recently isolated from phaeochromocytoma. We report here the distribution and characterization of immunoreactive AM and gene expression of AM in human gastrointestinal tissue. Using a sensitive radioimmunoassay system for the peptide, immunoreactive human AM was detected in the stomach, duodenum, jejunum, ileum and colon. The AM concentration of these tissues was about 0.4-0.8 pmol/g wet tissue. Reverse phase and gel filtration high-performance liquid chromatographies showed that most of the immunoreactive AM in stomach and jejunum was identical to authentic human AM. By northern blot analysis, human AM mRNA was found to be expressed ubiquitously in the human gastrointestinal tissues. Furthermore, an immunohistochemical study revealed that immunoreactive AM cells were present in the gastrointestinal glands. These results suggest that AM may play some role as a gastrointestinal hormone.

Developmental effects on intersexual and intrasexual variation in growth and reproduction in a lizard with temperature-dependent sex determination

The mechanisms that control growth and reproduction have received considerable attention by molecular and cellular endocrinologists, yet there has been relatively little effort to link these two aspects of physiology. On the other hand, evolutionary biologists have long commented on the relationship between growth and reproduction in many species, yet have generally neglected the mechanisms underlying such complex traits. An approach that integrates the multiple proximate levels promises to provide significant insight into the evolution of neuroendocrine control mechanisms. In this chapter, we take this approach in reviewing environmental influences on growth and reproduction in the leopard gecko, Eublepharis macularius. In this species, incubation temperature during embryonic development not only determines gonadal sex, but also underlies within-sex differences in growth, adult morphology, aggressiveness, reproductive physiology and behaviour, and brain organization. Thus, the leopard gecko is an excellent model to elucidate the developmental interactions among the environment and the endocrine and nervous systems that control growth and reproduction.

[Surgical stabilization of multiple rib fractures successfully achieved with the use of long metalic plates]

Surgical stabilization of multiple rib fractures in 5 male patients was successfully achieved with the use of orthopedic A-O metalic plates, which are called reconstruction plates. In each patient, we prevented deformity of the rib cage and flail chest which frequently occurs after multiple rib fractures. Three of these patients received emergency operations because of severe hemopneumothorax and flail chest due to crushing injuries to the chest. They were treated by the standard thoracotomy, hemostasis of intrapleural bleeding, and stabilization of fractured ribs with reconstruction plates, in addition two of the patients underwent a single lobectomy to control the pulmonary hemorrhage. Another two patients were treated with mechanical ventilation and closed-tube thoracotomy following the chest trauma because their thoracic bleeding from drainage tubes was tolerable. But flail chest and respiratory insufficiency did not improve, in spite of positive controlled ventilation as a mode of internal pneumatic stabilization. Then surgical stabilization of the fractured ribs with these plates was carried out ten to twelve days after the accidents in each case. All patients tolerated the surgical procedures well and were successfully removed from the respirator, demonstrating complete stability of the chest wall. The long metal reconstruction plates with many perforations were very useful for the external fixation of segmentary fractured ribs as an external brace. This was because they were long enough to cover the whole length of the fractured ribs and moderately soft enough to be appropriately bent or twisted by hand at the time of operation. Moreover a number of holes in it allowed the suture to pass through the plate and rib, avoiding displacement of the prosthesis. This is the first report which describes the usefulness of orthopedic reconstruction plates for the stabilization of multiple rib fractures.

Decrease in circulating and urine adrenomedullin concentrations in stroke-prone spontaneously hypertensive rats

Adrenomedullin (AM) is a peptide with potent vasodilatory and hypotensive properties. Plasma AM levels in rats with experimentally induced hypertension, such as Dahl salt-sensitive rats and two-kidney, one-clip hypertensive rats, are higher than those in normotensive rats. We previously noted, however, that plasma AM levels in spontaneously hypertensive rats (SHR) are similar to those in Wistar-Kyoto rats. To define the role of AM in rats with severe hypertension, we investigated changes in circulating and tissue AM levels in stroke-prone spontaneously hypertensive rats (SHRSP/Izm). The immunoreactive rat AM levels in plasma, urine, and tissue measured with a sensitive radioimmunoassay, and the AM mRNA levels in various tissues in 15-wk-old SHRSP/Izm were compared with those in age-matched Wistar-Kyoto rats (WKY/Izm). The plasma and urinary AM levels in SHRSP/Izm were significantly lower than those in WKY/Izm [plasma AM, 2.14+/-0.06 (SE) vs. 3.24+/-0.16 fmol/ml, p< 0.001; urinary AM, 16.36+/-3.21 vs. 36.12+/-6.09 fmol/ml, p< 0.01]. A negative correlation was found between the plasma AM level and the systolic blood pressure in both SHRSP/Izm and WKY/Izm. Reverse-phase high-performance liquid chromatography showed that the molecular components of plasma immunoreactive AM in SHRSP/Izm were similar to those in WKY/Izm. Furthermore, tissue AM levels in various organs in SHRSP/Izm were not lower than those in WKY/Izm. In conclusion, low levels of circulating AM may contribute to the maintenance of high blood pressure in 15-wk-old SHRSP/Izm. These low plasma AM levels may be caused by accelerated metabolism of circulating AM in SHRSP/Izm.

Comparison of clinical outcome between histidine-triptophan-ketoglutalate solution and cold blood cardioplegic solution in mitral valve replacement

BACKGROUND

This study was conducted to compare the effect of histidine-triptophan-ketoglutalate solution (HTK) with that of cold blood cardioplegic solution (CBC) in mitral valve surgery.

METHOD

Forty-six patients who underwent mitral valve replacement between January 1994 and December 1996 were enrolled in this study. Twenty patients received HTK (HTK group), while 27 patients had CBC (CBC group) as myocardial protection. HTK was given as a single high dose, whereas CBC was used in the usual multidose format.

RESULT

The doses of inotropic agent at the end of extracorporeal circulation did not differ between the HTK group and the CBC group. Creatine kinase values (units) on day 1 and day 2 were 1140+/-412, 921+/-436 for the HTK group and 904+/-335, 816+/-420 for the CBC group, respectively (p = NS). Spontaneous defibrillation occurred in 26% of the CBC group and 90% of the HTK group (p < 0.05). Pacing was temporarily used in 20% of the HTK group and 44% of the CBC group after extracorporeal circulation (p < 0.05).

CONCLUSIONS

These results suggest that HTK provided more adequate myocardial protection in mitral valve surgery.

Experimental studies on three types of heparin-coated cardiopulmonary bypass circuits

In cardiovascular operations, we have usually used heparin-coated cardiopulmonary bypass circuits with low systemic heparinization. Three types of heparin-coated cardiopulmonary bypass circuits are available in Japan: 2 of the 3 have covalent heparin bonding, and the other has ionic heparin bonding. We studied these circuits in ex vivo experiments to explore which were the best in terms of biocompatibility. In this study we compared the Carmeda system (Medtronic) and the Capiox system (Terumo) with covalent heparin bonding, and the Duraflo-II (Baxter) with ionic heparin bonding, evaluating them in ex vivo experiments. They were primed with fresh human blood, and we studied and compared the platelet counts, fibrinogen, D-dimmer, beta-thioguanine (TG), thrombin-antithrombin complex (TAT), and C3a and C4a of each of them. Additional research will be presented in the future.

The method for keeping low perfusion flow weaning from centrifugal pumps: an evaluation of hemolysis in the circulator units

Currently, the clinical application of extracorporeal and assisted circulation using centrifugal pumps is becoming popular. However, a problem in the use of centrifugal pumps is the difficulty in controlling the flow rate when it is a low range. Although we have been controlling the flow rate with a control unit that simply squeezes the blood outlet tube from the outside, hemolysis resulting from turbulent flow in the tube was discovered. Therefore, this control procedure was evaluated experimentally. Two groups were tested as follows: in Group A (n = 10), the tube was squeezed from the outside using the control unit, and in Group B (n = 10), no control unit was used. Blood in each circuit was circulated at 1,500 rpm, and the flow rate was controlled to 250 ml/min using the control unit for Group A. Time-course changes of lactate dehydrogenase (LDH) and free hemoglobin in the blood were measured during 8 h of circulation. There were no significant differences between the 2 groups in the mean values of LDH and free hemoglobin. Therefore, the present low flow rate control provided by the control unit makes it appear to be a simple and useful apparatus for controlling blood circulation using centrifugal pumps.