CT-based deep learning enables early postoperative recurrence prediction for intrahepatic cholangiocarcinoma

Preoperatively accurate evaluation of risk for early postoperative recurrence contributes to maximizing the therapeutic success for intrahepatic cholangiocarcinoma (iCCA) patients. This study aimed to investigate the potential of deep learning (DL) algorithms for predicting postoperative early recurrence through the use of preoperative images. We collected the dataset, including preoperative plain computed tomography (CT) images, from 41 patients undergoing curative surgery for iCCA at multiple institutions. We built a CT patch-based predictive model using a residual convolutional neural network and used fivefold cross-validation. The prediction accuracy of the model was analyzed. We defined early recurrence as recurrence within a year after surgical resection. Of the 41 patients, early recurrence was observed in 20 (48.8%). A total of 71,081 patches were extracted from the entire segmented tumor area of each patient. The average accuracy of the ResNet model for predicting early recurrence was 98.2% for the training dataset. In the validation dataset, the average sensitivity, specificity, and accuracy were 97.8%, 94.0%, and 96.5%, respectively. Furthermore, the area under the receiver operating characteristic curve was 0.994. Our CT-based DL model exhibited high predictive performance in projecting postoperative early recurrence, proposing a novel insight into iCCA management.

[A Case of Ectopic Pheochromocytoma between the Abdominal Aorta and Inferior Vena Cava]

We report a case of ectopic pheochromocytoma which is relatively rare. A 50-year-old man was found to have an abdominal tumor on a medical examination, and contrast-enhanced computed tomography showed a retroperitoneal tumor between the abdominal aorta and the inferior vena cava. As a result of close examinations, an ectopic pheochromocytoma was suspected. He was asymptomatic and suspected infiltrating into great vessels, but possibility of a malignant neoplasm could not be ruled out for the tumor had a tendency to enlarge, the resection of the tumor was performed. During the operation, the invasion of the tumor into the great vessels was denied and the tumor was completely resected. Large fluctuation of the blood pressure was not observed during the operation. Histopathological evaluations of the resected specimen revealed the ectopic pheochromocytoma. A pheochromocytoma was newly defined as a tumor with malignant potential for metastasis in all cases by the WHO classification published in 2017. He was diagnosed as moderately malignant by GAPP score, therefore the careful follow-up was considered necessary in the future.

[A Case of Metastatic Breast Cancer with BRCA1 Mutation after Breast Reconstruction and Pregnancy]

We present the case of a 31-year-old woman with a chief complaint of a left breast mass. The patient visited our department for an evaluation of this left breast mass. Left breast cancer(cT1cN0M0, cStage Ⅰ, triple negative type)was diagnosed, and left partial mastectomy and sentinel node biopsy were performed. Although the pStage was the same prior to surgery, a BRCA1 mutation was identified on genetic testing. After administration of postoperative adjuvant chemotherapy (epirubicin, cyclophosphamide, and paclitaxel), consorted mastectomy, tissue expander insertion, and breast reconstruction with silicone implant were performed. Spontaneous pregnancy occurred 1 year and 10 months after the first operation. She had an uneventful delivery with a normal course of labor 2 years and 6 months after the surgery. Two years and 11 months after the first operation, she visited our institution with complaints of headache, dizziness, and difficulty eating. Upon assessment, brain, lung, liver, and bone metastases were identified on contrast-enhanced computed tomography. Concentrated glycerin and fructose, steroid administration, and whole-brain irradiation improved the symptoms due to cerebral edema. Thereafter, olaparib was started, and treatment was continued while maintaining partial response(PR).

[Two Cases in Which Simultaneous Laparoscopic Surgery and Breast Cancer Surgery Using a Head-Mounted Monitor Were Useful]

Herein, we report on how we were able to reduce the operation time by simultaneously performing laparoscopic surgery and breast cancer surgery using a head-mounted monitor(HMS-3000MT, Sony corporation). Case 1: 60s, female. A 5.5 cm leiomyoma was found in the central thoracic esophagus, and a 1 cm breast cancer was found in the C region of the left mammary gland. Subtotal esophagectomy with right thoracotomy and laparoscopy and a left partial mastectomy were performed. For the abdominal surgery, HMS-3000MT was used under hand-assisted laparoscopy, and a left partial mastectomy was performed concurrently. Operation time was 367 minutes(simultaneous surgery for 56 minutes). Esophagus: leiomyoma, 50×45 mm; and mammary gland: 16×15 mm, pTis(DCIS), pN0(sn), cM0, and pStage 0. Case 2: 70s, female. A 3 cm sized GIST was found on the posterior wall of the middle gastric body, and a breast cancer of 1.3 cm was also found in the B region of the right mammary gland. Using HMS-3000MT, laparoscopic local resection of the stomach and right total glandectomy were performed concurrently. Operation time was 114 minutes(simultaneous surgery for 58 minutes). Stomach: GIST, 25×22 mm, and modified Flecher classification low risk; and mammary gland: invasive ductal carcinoma, 15×15 mm, pT1c, pN0(sn), cM0, and pStage Ⅰ. Conclusion: In 2 fields of surgery, simultaneous surgery using HMS-3000MT was considered to be a useful method to shorten the operation time.

Keratinocytes: innate immune cells in atopic dermatitis

The skin is a unique immune organ that constitutes a complex network of physical, chemical and microbiological barriers against external insults. Keratinocytes are the most abundant cell type in the epidermis. These cells form the physical skin barrier and represent the first line of the host defense system by sensing pathogens via innate immune receptors, initiating anti-microbial responses and producing various cytokines, chemokines and anti-microbial peptides, which are important events in immunity. A damaged epidermal barrier in atopic dermatitis allows the penetration of potential allergens and pathogens to activate keratinocytes. Among the dysregulation of immune responses in atopic dermatitis, activated keratinocytes play a role in several biological processes that contribute to the pathogenesis of atopic dermatitis. In this review, we summarize the current understanding of the innate immune functions of keratinocytes in the pathogenesis of atopic dermatitis, with a special emphasis on skin-derived anti-microbial peptides and atopic dermatitis-related cytokines and chemokines in keratinocytes. An improved understanding of the innate immunity mediated by keratinocytes can provide helpful insight into the pathophysiological processes of atopic dermatitis and support new therapeutic efforts.

[A Case of Laparoscopic Distal Gastrectomy for Gastric Cancer with an Adachi Type Ⅵ Group 24 Vascular Anomaly]

We report a case of successful laparoscopic distal gastrectomy for gastric cancer with an Adachi type Ⅵ group 24 vascular anomaly. A male in his 60s exhibited a type 0-Ⅱa plus Ⅱc lesion at the lesser curvature of the gastric angle by esophagogastroduodenoscopy and was diagnosed with tub2. He was referred to us for surgical treatment. The clinical diagnosis was cT1bN0M0, and cStage Ⅰ. Preoperative multidetector-row computed tomography(MDCT)showed an Adachi type Ⅵ group 24 vascular anomaly. At laparoscopic surgery, we dissected No. 8a lymph nodes with exposure of the surface of the portal vein because the common hepatic artery was absent. The left gastric artery and splenic artery formed a common trunk. As there are various kinds of vascular anomalies of the celiac artery branch, we must understand the arterial running pattern prior to gastric surgery. This technique is more useful in laparoscopic surgeries where tactile sensation is limited. To prevent perioperative and postoperative complications, we must recognize the anomaly pattern prior to surgery using MDCT.

[A Case in Which Trastuzumab Combined Chemotherapy Was Effective for Recurrence of Post-Operative Gastric Cancer with Partial HER2 Overexpression]

We report a case in which recurrent partial HER2-positive gastric cancer showed complete clinical response to capecitabine (Cape)/oxaliplatin(L-OHP/OX)(CapeOX)plus trastuzumab(Tmab)combined chemotherapy for 32months. A 65-yearold man underwent distal gastrectomy, D2 lymph node dissection, and Roux-en-Y reconstruction for type 2 gastric cancer of the prepyloric anterior wall in December 2014. Pathological stage was as follows: L, ant, Type 2, 32×22 mm, tub1>tub2> por1, pT2(MP), int>med, INF c>a, Ly1a, V0, pN0, cM0, cH0, cP0, pCY0, pStage I B, pPM0(60mm), pDM0(75mm), pR0. Immunostaining of the tumor indicated overexpression of the HER2 gene in more than 10% of the well differentiated tubular adenocarcinoma(tub1). Nineteen months post-surgery, pancreatic head lymph node metastasis was diagnosed, and we started CapeOX plus Tmab combined chemotherapy. After 19 courses, the metastatic lymph node reduced its size until we could not detect it on CT. We continued treatment for 45 courses(about 32 months). During the courses, there were adverse events such as peripheral neuropathy(Grade 3, CTCAE v5.0), which required interruption of L-OHP, and oral mucosal ulcer (Grade 2).

[A Case of Laparoscopic Low Anterior Resection and Adrenalectomy for Rectal Cancer and Adrenal Tumor]

A 70-year-old woman had consulted a doctor at a former clinic because of bloody stool and colonoscopy revealed a type 2 tumor of the rectum. She was referred to our hospital for further examinations and treatment. Preoperative blood examination showed an elevated HbA1c level of 10.2%. Abdominal CT showed a 25mm tumor in the left adrenal gland. The patient was diagnosed with adrenal Cushing's syndrome based on low ACTH levels, disappearance of circadian variation in blood cortisol levels, lack of inhibition by dexamethasone loading, and high urinary cortisol levels. Laparoscopic adrenalectomy for left adrenal tumor and low anterior resection for rectal cancer were performed. The pathological findings were rectal cancer, pap, pT1b(SM), pN0, cM0, fStageⅠof rectal cancer, and adrenal cortical adenoma. The postoperative course was uneventful with steroid replacement therapy. The ileal stoma was closed 4 months after surgery. Surgery in hyperadrenalism requires perioperative steroid replacement therapy because of the risk of postoperative acute adrenal failure. In addition, when diabetes is poorly controlled, we should be careful about risk of leakage and susceptibility to infection.

[A Case of Appendiceal Mucinous Adenocarcinoma Detected with a Bladder Tumor]

A 74-year-oldwoman hadconsultedthe department of urology in our hospital because of microscopic hematuria. Cystoscopy revealeda urinary bladder tumor, suspectedas an adenocarcinoma basedon biopsy. MRI showeda cystic tumor of the appendix with vesical fistula; therefore, she underwent an operation with a diagnosis of appendiceal cancer invading the urinary bladder. During the operation, we found that the appendix sunk into the urinary bladder with right adnexa. Therefore, we performed ileocecal resection, partial resection of the urinary bladder, and right adnexectomy. Macroscopically, the bladder was filled with a large number of mucus lumps. A papillary tumor, 4 cm in size, growing in the lumen of the bladder was detectedat the invasion site. Microscopically, proliferating carcinoma cells in a papillary form were observedin the lumen of the appendix with mucus production, invading the wall of the urinary bladder at the fundus of the appendix. Thus, the patient was diagnosed with mucinous adenocarcinoma of the appendix(V, type 1, 45×30 mm, muc, pT4b[SI, urinary bladder], int, INF c, ly0, v0, pN0, cM0, pStage II ). Primary appendiceal cancer invading the urinary bladder is very rare; herein, we report a rare case of appendiceal mucinous adenocarcinoma detected with a bladder tumor and present a literature review.

Oral administration of milk-derived phospholipids inhibits penetration of cutaneous nerve fibres into epidermis in a mouse model of acute dry skin

The density of intraepidermal nerve fibres has been shown to be higher in itchy dry skin than in healthy skin, suggesting that epidermal hyperinnervation is at least partly involved in peripheral itch sensitization. We investigated whether oral administration of milk-derived phospholipids (MPLs) would inhibit epidermal hyperinnervation in a mouse model of dry skin. We found that the number of intraepidermal nerve fibres was significantly lower in the MPL group than in the control group. Expression of nerve growth factor (NGF) levels in the epidermis was significantly decreased by oral administration of MPLs, whereas expression of semaphorin (Sema)3A, a nerve repulsion factor, was increased in the MPL group. These results suggest that dietary MPLs attenuate the penetration of nerve fibres into the epidermis by reducing epidermal NGF levels and increasing Sema3A level. Thus, dietary MPLs may have beneficial effects in the prevention and/or alleviation of dry skin-induced itch by reducing intraepidermal nerve fibre density.

Intrasplenic Transplantation of Encapsulated Cells: A Novel Approach to Cell Therapy

Cell therapy is likely to succeed clinically if cells survive at the transplantation site and are protected against immune rejection. We hypothesized that this could be achieved with intrasplenic transplantation of encapsulated cells because the cells would have instant access to oxygen and nutrients while being separated from the host immune system. In order to provide proof of the concept, primary rat hepatocytes and human hepatoblastoma-derived HepG2 cells were used as model cells. Rat hepatocytes were encapsulated in 100-kDa hollow fibers and cultured for up to 28 days. Rat spleens were implanted with hollow fibers that were either empty or contained 1 × 107 rat hepatocytes. Human HepG2 cells were encapsulated using alginate/poly-l-lysine (ALP) and also transplanted into the spleen; control rats were transplanted with free HepG2 cells. Blood human albumin levels were measured using Western blotting and spleen sections were immunostained for albumin. Hepatocytes in monolayer cultures remained viable for only 6–10 days, whereas the cells cultured in hollow fibers remained viable and produced albumin throughout the study period. Allogeneic hepatocytes transplanted in hollow fibers remained viable for 4 weeks (end of study). Free HepG2 transplants lost viability and function after 7 days, whereas encapsulated HepG2 cells remained viable and secreted human albumin at all time points studied. ALP capsules, with or without xenogeneic HepG2 cells, produced no local fibrotic response. These data indicate that intrasplenic transplantation of encapsulated cells results in excellent survival and function of the transplanted cells and that the proposed technique has the potential to allow transplantation of allo- and xenogeneic cells (e.g., pancreatic islets) without immunosuppression.

Intrasplenic Transplantation of Encapsulated Genetically Engineered Mouse Insulinoma Cells Reverses Streptozotocin-Induced Diabetes in Rats

Pancreatic islet transplantation is limited by shortage of donor organs. Although β-cell lines could be used, their secretion of insulin is characteristically glucose independent and immunoisolation is required. Here we show that intrasplenic transplantation of encapsulated glucose-responsive mouse insulinoma cells reversed streptozotocin (STZ)-induced diabetes in rats. MIN-6 cells derived from a transgenic mouse expressing SV 40 large T antigen in pancreatic β-cells were transfected with minigene encoding for human glucagon-like-peptide-1 under the control of rat insulin promoter. The cells were encapsulated in alginate/poly-L-lysine and used for cell transplantation in STZ-diabetic rats. Rats with nonfasting blood glucose (n-FBG) greater than 350 mg/dl were used. In group I rats (n = 6) 20 million encapsulated cells were injected into the spleen. Group II rats (n = 6) received empty capsules. n-FBG was measured biweekly. After 4 and 8 weeks, an intraperitoneal glucose tolerance test (IPGTT) was performed in group I; normal rats served as controls. Plasma insulin level was measured every other week (RIA). After 8 weeks, spleens were removed 1 day before sacrifice. In rats transplanted with cells the n-FBG was 100—150 mg/dl until the end of the study. After splenectomy, all cell recipients became diabetic (glucose 400 ± 20 mg/dl). Transplanted rats showed increase in body weight and insulin production (3.3 ± 1.0 ng/ml versus 0.92 ± 0.3 ng/ml; p < 0.01) and had normal IPGTT. Spleens contained capsules with insulin-positive cells. Overall, data from this work indicate that intrasplenic transplantation of xenogeneic encapsulated insulin-producing cells without immunosuppression reversed diabetes in rats. Excellent survival and function of the transplanted cells was due to the fact that the cells were separated from the bloodstream by the immunoisolatory membrane only and insulin was delivered directly to the liver (i.e., in a physiological manner).

[A Case of Primary Sclerosing Cholangitis Difficult to Distinguish from a Hilar Cholangiocarcinoma]

A 78-year-old man, who had presented with onset of ulcerative colitis at the age of 56 years and had been in remission for the past several years, attended our hospital with a diagnosis of obstructive jaundice. A hilar cholangiocarcinoma with right hepatic artery invasion was suspected on contrast enhanced CT. An endoscopic retrograde cholangiography indicated Bismuth type 2 stenosis. The stenotic bile duct brushings revealed no malignancy. Primary sclerosing cholangitis(PSC)and IgG4- related cholangitis were included in the differential diagnosis; however, a significant result could not be obtained in any other examinations. A hilar cholangiocarcinoma could not be ruled out, and rt. hepatic lobectomy and caudate lobectomy with resection of the extrahepatic bile duct were performed after obtaining informed consent. The histopathological findings revealed no atypical cells in the stenotic lesion, but fibrosis and inflammatory cell infiltration were observed around the bile duct. These findings were consistent with PSC. On the other hand, atypical cell proliferation with lymph duct infiltration was found in the mucosa of the gall bladder. It is difficult to preoperatively diagnose PSC localized to the hilar bile duct, and if possible, the existence of concomitant malignant lesions in the biliary tract should be considered.

Preoperative Chemotherapy with Bevacizumab Extends Disease-free Survival After Resection of Liver Metastases from Colorectal Cancer

BACKGROUND

The benefit of preoperative chemotherapy for patients with liver metastases from colorectal cancer remains unclear. We evaluated the efficacy of preoperative chemotherapy with bevacizumab in such patients, and attempted to identify clinical predictors of recurrence.

PATIENTS AND METHODS

Between February 2007 and December 2013, a total of 65 liver resections for colorectal metastases were performed at our Institution; 47 patients underwent preoperative chemotherapy, which consisted of modified FOLFOX6 (mFOLFOX6) in 42 cases. The last clinical follow-up was in December 2014. Demographic and clinicopathological factors were reviewed for each patient, and potential predictors of recurrence after liver resection were evaluated. Disease-free survival (DFS) and overall survival (OS) were compared with respect to clinicopathological factors.

RESULTS

The 3- and 5-year OS rates were 73.9% and 62.5%, respectively. The time at which metastases appeared, and the extent of metastasis according to the Japanese classification did not significantly affect OS or DFS. However, mFOLFOX6 plus bevacizumab significantly improved DFS compared to mFOLFOX6 alone. Patients did not experience worsening of hepatic dysfunction during preoperative chemotherapy, and tolerated surgical stress well.

CONCLUSION

Preoperative chemotherapy with bevacizumab appears to be an effective treatment modality for liver metastases from colorectal cancer, and results in prolonged DFS.

[A Case of MALT Lymphoma of the Rectum Treated with Intersphincteric Resection (ISR)]

A 60-year-old woman visited a local hospital complaining of melena. On colonoscopy, she was found to have 2 tumors in the lower rectum, each of approximately 10 mm in diameter. A biopsy of the tumors indicated MALT lymphoma, and the patient was referred to our hospital. We performed intersphincteric resection (ISR) with lymph node dissection according to the guidelines for the treatment of rectal cancer for 2 reasons. One reason was that eradication therapy for Helicobacter pylori was not effective in this case, and we needed to obtain an accurate histopathological diagnosis as to whether the patient had diffuse large B cell lymphoma (DLBCL). The other reason was that it was localized disease in the rectum, and that curative resection could be performed. MALT lymphoma of the rectum occurs frequently in the lower rectum and has a relatively good prognosis. It is important to consider the quality of life when selecting an operative method. ISR is thought to be a good option.

[A Case of Von Hippel-Lindau Disease with Nonfunctioning Pancreatic Neuroendocrine Tumors Treated by Duodenum-Preserving Resection of the Head of the Pancreas and Spleen-Preserving Resection of the Tail of the Pancreas]

A 26-year-old woman presented to our department with a diagnosis of multiple nonfunctioning pancreatic neuroendocrine tumors. She had a family history of pheochromocytoma and a medical history of bilateral adrenalectomy for pheochromocytoma at the age of 25 years. During follow-up treatment for adrenal insufficiency after the surgery, highly enhanced tumors in the pancreas were detected on contrast-enhanced CT. Other examinations found that the patient did not satisfy the clinical criteria for von Hippel-Lindau (VHL) disease. Considering her age and risk of developing multiple heterotopic and heterochronous tumors, we performed a duodenum-preserving resection of the head of the pancreas and spleen-preserving resection of the tail of the pancreas with informed consent. The histopathological findings revealed that all of the tumors were NET G1. She underwent genetic testing postoperatively and was diagnosed with VHL disease. This diagnosis meant that we were able to create an optimal treatment plan for the patient. If a tumor predisposition syndrome is suspected, VHL disease should be borne in mind and genetic testing after genetic counseling should be duly considered.

[A Case of Extranodal Nasal Type, NK／T Cell Lymphoma in the Ileum with Perforated Peritonitis during Chemotherapy]

A 65-year-old woman complaining of melena and a high fever was admitted to our hospital. Colonoscopy revealed a large tumor with a wide ulcer in the terminal ileum, and nasal type, extranodal NK/T cell lymphoma was suspected via biopsy. Owing to rapid progression of hepatocellular damage with hepatomegaly and splenomegaly, chemotherapy with CHOP was initiated immediately. Two days later, the patient developed panperitonitis, and emergency laparotomy was performed. The tumor in the terminal ileum widely adhered to the bladder, where a deep perforated ulcer was found, for which palliative ileocecal resection was performed. Enlargement of the residual tumor caused an abdominal abscess, intestinal obstruction, and hepatic failure, and the patient died 75 days after surgery. In summary, we initiated chemotherapy to control the deteriorating systemic condition of the patient. However, nasal type, extranodal NK/T cell lymphoma is a rapidly progressing lymphoma occasionally accompanied by perforation of the tumor. Surgery preceding chemotherapy should be considered an alternative treatment.

[A Case of Pseudo-Meigs Syndrome Associated with Metachronous Ovarian Metastasis from Ascending Colon Cancer]

We experienced a case of pseudo-Meigs syndrome associated with metachronous metastasis to the ovary from ascending colon cancer. A 65-year-old woman underwent curative surgery for ascending colon cancer at another hospital. A follow-up CT carried out 3 months after the surgery revealed a right ovarian tumor and a large amount of ascites. The patient was diagnosed with ovarian metastasis from ascending colon cancer with carcinomatous peritonitis. Palliative care was recommended, and she presented at our department for a second opinion. In spite of a large amount of ascites and pleural effusion, no disseminating tumor was detected on contrast-enhanced CT at our hospital, and we recommended that she undergo a diagnostic laparotomy. The laparotomy was negative for carcinomatous peritonitis and a right oophorectomy was performed. The histopathological findings indicated that the ovarian tumor was consistent with metastasis from ascending colon cancer. After the surgery, we initiated chemotherapy with mFOLFOX6+bevacizumab and the symptoms were well controlled. A follow-up CT carried out 11 months after the surgery revealed a left ovarian tumor and increased ascites, and the patient underwent a left oophorectomy. Then, chemotherapy with the same regimen was administered for 12 months, and she did not develop any signs of recurrence for 27 months after the surgery. Ovarian metastasis from colon cancer may occasionally cause pseudo-Meigs syndrome, and it is important to be aware of the usefulness of oophorectomy for the control of ascites and pleural effusion.

[Preoperative Chemotherapy and Risk Factors for Colorectal Liver Metastases]

Between February 2007 and December 2013, 65 liver resections for colorectal metastases were performed in our institution. Preoperative chemotherapy was conducted in 47 patients, of whom 42 were treated with modified FOLFOX6 (mFOLFOX6)-based preoperative chemotherapy. For cases of solitary tumors smaller than 2 cm that are located in the liver surface area, we selected upfront surgery. In the patients who underwent preoperative chemotherapy and upfront surgery, the 3-year OS was 73.9% (Grade A: 81.8%, Grade B: 77.8%, and Grade C: 0%) and the 5-year OS was 62.5%. The 3-year OS in the preoperative chemotherapy group was 63.3%. OS did not differ significantly between the patients who were grouped according to the time of metastasis onset or the extent of metastasis according to the Japanese classification. In the multivariate analysis, no statistical differences were found between the risk factors for recurrence. However, further follow up is needed. Moreover, we believe that the relationships of morphological response to chemotherapy, pathological response, and clinical prognosis should be assessed in the future.

Computed tomographic lymphography for sentinel lymph node biopsy in male breast cancer: report of two cases

Male breast cancer is rare, accounting for less than 1% of breast cancers. Because of its rarity evidence of the usefulness sentinel lymph node biopsy (SLNB) for male breast cancer has not been established. Moreover, a navigation system which can easily determine the incision site of SLNB is needed because a second incision for SLNB is necessary in most cases. We report successful computed tomographic lymphography (CTLG)-guided SLNB in two male breast cancer cases: the first patient was a 79-year-old man and the second was a 64-year-old man. Both had presented with a lump behind the nipple. Clinical diagnoses were early breast carcinoma in both cases. The second patient took tamoxifen 20 mg daily as neoadjuvant endocrine therapy. SLNs were clearly visualized by CTLG, allowing mastectomies with SLNB to be performed. Both SLNB were negative, such that axillary lymph node dissection was not needed. Preoperative CTLG is useful for visualizing lymph flow and detecting SLN in male breast cancer.

Feasibility and potential benefits of adjuvant chemotherapy with S-1 in patients with curative resected advanced biliary tract cancer: A multicenter trial

e15179

Background: S-1 chemotherapy is reported to be effective for treating metastatic and unresectable biliary tract cancer (BTC). We assessed the safety and feasibility of adjuvant S-1 chemotherapy in patients with curative resected advanced BTC. Methods: Patients with pathological stage II, III, or IVa BTC (according to JSBS) who underwent radical resection received oral S-1 (80 mg/m2/day) for 2 consecutive weeks every 3 weeks (1 cycle). Patients were aged 20–80 years, had a performance status of <1, and provided informed consent. The treatment was repeated until 1 year after surgery. The primary endpoint was feasibility of the adjuvant chemotherapy with S-1. The secondary endpoints were safety, disease-free survival (DFS), and overall survival (OS). Results: We enrolled 40 patients, but 5 patients were excluded on the basis of eligibility criteria (4 patients) or no drug administration (1 patient). We analyzed data from 35 patients (29 men and 6 women with a median age of 68 years) between January 2009 and November 2011. The feasibilities of 6-month and 12-month administration of S-1 were 65.7% (95% confidence interval [CI]: 47.8–80.9%) and 45.7% (95% CI 28.8–63.4%), respectively. Grade 3 neutropenia and anemia were observed in 2.9% and 5.7% of cases, respectively. Grade 3 non-hematological toxicities included anorexia in 14.3%, fatigue in 8.6%, and nausea in 2.9% of cases. No grade 4 hematological or non-hematological toxicities were observed, and no treatment-related deaths occurred. The 1-year OS was 91.4% (95% CI: 76.6–97.2%), and the 1-year DFS was 68.6% (95% CI: 51.7–81.7%). Conclusions: Adjuvant chemotherapy with S-1 for curative resected advanced BTC patients was both safe and feasible. Although the follow-up period was insufficient to evaluate OS and DFS, adjuvant chemotherapy with S-1 is believed to have improved the prognosis.

[A case of advanced rectal cancer treated effectively with intersphincteric resection and preoperative chemotherapy]

An approximately 50-year-old man with rectal cancer(RbP)[ cT3(cA), cN3, cM0, and cStage IIIb] who desired anus preservation was administered mFOLFOX6 therapy. This treatment decreased the size of both the tumor and the lymph node, and intersphincteric resection (ISR) was performed. Histopathology demonstrated tumor invasion beyond the muscularis propria, and the histological effectiveness was Grade 2. Because computed tomography showed an abscess in the dissection area, we performed postoperative drainage and the patient recovered. Therapy with mFOLFOX6 was repeated after the patient was discharged from hospital. Increased adoption of anus-preserving surgery is expected via successful control of local recurrence and distant metastasis by neoadjuvant chemotherapy.

Gene expression of ATP-binding cassette transporters during liver regeneration after 90% hepatectomy in rats

Liver damage with hyperbilirubinemia during regeneration of the small liver is the major hurdle to expand the indications of adult living donor liver transplantation. We performed a large-scale gene expression analysis of the regenerating liver after a 90% hepatectomy in rats, and analyzed the changes in the gene expression patterns related to the ATP-binding cassette (ABC) transporters. RNAs were prepared from 3 rat livers at 0, 24, 72 and 168 h after a 90% hepatectomy. The gene expression profile was analyzed by the Rat Genome 230 2.0 array with special references to the ABC transporters. Among 31,042 probes, 1,587 reported genes were identified as either upregulated or downregulated more than 2-fold. Among 20 ABC transporter genes, multidrug resistance protein (MRP) 2 and organic anion transporting polypeptide (OATP) 1 were significantly downregulated, while MRP1 and MRP3 tended to be expressed. These genetic changes were confirmed by real-time PCR. A microarray analysis demonstrated not only an extensive gene expression profile in the regenerating liver but more specific molecular events related to bilirubin transport at the same time. Changes in the expression pattern of the ABC transporters, therefore, seem to be the key event in liver failure during liver regeneration.

Abnormal tau deposition in neurons, but not in glial cells in the cerebral tissue surrounding arteriovenous malformation

We report an autopsy case of arteriovenous malformation (AVM) of the right frontal lobe in a 50-year-old man, in whom post mortem examination revealed massive tau deposition in the affected cerebral cortex. The patient was diagnosed as having AVM at the age of 21 years, and died of unknown cause at the age of 50 years. Immunostaining with anti-phosphorylated tau antibody (AT8) revealed many NFTs and neuropil threads, but not glial tau accumulation, in the right frontal cortex surrounding the AVM. The NFTs and neuropil threads contained both 3-repeat and 4-repeat tau. Ultrastructurally, the NFTs consisted of paired helical filaments. In the other brain areas, a few NFTs were found in the parahippocampal gyrus. There was no amyloid deposition in the brain. A variety of disease conditions, including brain tumor, viral encephalitis, angioma and cervical spondylotic myelopathy, have been reported to show Alzheimer-type NFTs. The present findings indicate that abnormal tau deposition can occur in neurons, but not in glial cells, of the affected cerebral cortex surrounding AVM.

A bioartificial liver that combines plasma dialysis and whole liver perfusion

BACKGROUND/AIMS

The development of a bioartificial liver with xenogeneic hepatocytes requires sufficient hepatocyte mass for metabolic support, decreased immunogenicity, and prevention of viral transmission. Therefore, the authors developed a plasma dialysis system using a selective plasma filter, and combined this dialysis system with whole liver plasma perfusion (PDWLP). In this system, the patient's plasma was dialyzed with normal plasma recycled through the pig liver.

METHODOLOGY

Female inbred Large White pigs were used for the hepatic failure model and for liver donation. Fulminant hepatic failure (FHF) was induced by the intraportal administration of alpha-amanitin and lipopolysaccharide. Nine hours after this injection, the FHF pigs were connected to the dialysis system for 6 h (n = 5). Control FHF pigs were not connected to the dialysis system (n = 10).

RESULTS

Animal survival was lengthened, and cardiovascular stability was demonstrated in the PDWLP treated pigs. This system suppressed the production of substances that promote encephalopathy. The liver necrosis and neutrophil infiltration were significantly less in the experimental pigs.

CONCLUSIONS

The experimental treatment attenuated the progression of FHF. Extracorporeal liver, perfused with oxygenated plasma, functioned for 6 h without hyperacute rejection. This type of hybrid bioartificial liver may be useful for treating FHF patients.

A novel plasma filtration therapy for hepatic failure: preclinical studies

There is a need to develop artificial means of liver replacement and/or assistance with the aim of either supporting patients with borderline functional liver cell mass until their liver regenerates, or until a donor liver becomes available for transplantation. Selective plasma filtration is a novel approach to blood purification therapy designed to reduce the level of circulating toxins of hepatic and renal failure, mediators of inflammation and inhibitors of hepatic regeneration. The results of preclinical studies indicate that treatment of pigs with experimentally-induced fulminant hepatic failure is safe and effective in extending survival time and arresting brain swelling. In addition, the amount of ammonia, aromatic amino acids, IL6, TNFalpha and C3a removed during the 6-h treatment in the present study was higher by 34% to 175% than the total plasma content of those substances at the start of therapy.

Acute cholecystitis due to strangulation of a floating gallbladder by the lesser omentum

We report a unique case of acute cholecystitis due to strangulation of a floating gallbladder by the lesser omentum, which could be detected by abdominal ultrasonography. We believe this case to be the first case of reported literatures in English.

Plasma Exchange-based Plasma Recycling Dialysis System as a Potential Platform for Artificial Liver Support

We developed a plasma recycling dialysis (PRD) system based on plasma exchange (PE). In this system, rapid reduction of toxic substances and restitution of deficient essential substances are performed by PE, and subsequent blood purification is performed by dialysis between separated plasma recycled over a purification device and the patient's blood across the membrane of the plasma separator. This study was performed to demonstrate the safety and efficacy of this system. Hyperbilirubinemia was induced by ligating the bile duct in pigs, and 7 days later, only PE for 2 h (group PE) or PE for 2 h followed by PRD for 6 h (group PE + PRD) was performed. The separated plasma was recycled over anion-exchange resin through the extra fiber space of the plasma separator. The safety and efficacy of this system were evaluated based on the values of hemodynamic and laboratory parameters. Transfer from PE to PRD was completed in a few minutes. The hemodynamic status and blood cells counts were stable and hemolysis was not observed during the procedure. In the PE + PRD group, the concentrations of total bile acids continuously decreased (pretreatment, 155.5 +/- 40.6 microM; 2 h [end of PE], 76.1 +/- 14.4 microM; 8 h [end of PRD], 25.8 +/- 9.1 microM) and the value was significantly lower than in the PE group after 6 h. The total bilirubin also continuously decreased during PRD (pretreatment, 55.3 +/- 11.5 microM; 2 h [end of PE], 33.8 +/- 8.4 microM; 8 h [end of PRD], 18.6 +/- 7.7 microM) and was significantly lower than in the PE group after 4 h. No significant change was observed in other laboratory values. This PE-based PRD system allowed a swift transfer from PE to sorbent-based blood purification. The safety of this system was demonstrated and the removal of toxic substances was significant. This study confirmed the clinical utility of this system as a platform for artificial liver support.

Intrasplenic transplantation of encapsulated hepatocytes decreases mortality and improves liver functions in fulminant hepatic failure from 90% partial hepatectomy in rats

BACKGROUND

Encapsulated cell therapy might be a promising approach to enable cell transplantation without immunosuppression. This study investigates the viability and hepatic function of hepatocytes encapsulated with alginate/poly-L-lysine in vitro and the effect of the intrasplenic transplantation of cultured encapsulated hepatocytes on survival in 90% hepatectomized rats as a preliminary step toward allogeneic hepatocyte transplantation without immunosuppression.

MATERIALS AND METHODS

Rat hepatocytes were isolated and encapsulated using alginate/poly-L-lysine. Encapsulated hepatocytes were cultured for 28 days to measure cell viability, liver function, and morphology. Rats were treated with a 90% partial hepatectomy and then immediately underwent the intrasplenic transplantation of the cultured encapsulated hepatocytes, the capsule alone, or the allogeneic hepatocytes without the capsule. The survival rate, liver function, and cell morphology were assessed after transplantation.

RESULTS

The cultured encapsulated hepatocytes maintained their viability and showed better metabolic activity than day 0 cultured encapsulated hepatocytes. The encapsulated cells strongly expressed albumin and were positive for periodic acid-Schiff staining. Electron microscopy demonstrated that the microencapsulated hepatocytes retained the structural elements of hepatic cytoplasm and nuclei. Intrasplenic transplantation of the encapsulated hepatocytes increased the survival rate and improved the hepatic function. Encapsulated hepatocytes transplanted into rat spleen survived well and retained their hepatic function. Moreover, dramatic liver regeneration was observed 48 hr after transplantation in the group that received intrasplenic transplantations of encapsulated hepatocytes.

CONCLUSIONS

The intrasplenic transplantation of cultured encapsulated hepatocytes improved the survival rate of an acute liver failure rat model induced by a 90% partial hepatectomy.

Intraoperative blood lactate level as an early predictor of initial graft function in human living donor liver transplantation

This study was performed to investigate whether intraoperative changes in blood lactate levels after hepatic allograft reperfusion reflect initial graft function in living donor liver transplantation (LDLT).

PATIENTS AND METHODS

From 1994 to 2003, 15 of LDLT cases were divided into two groups based on the intraoperative blood lactate levels. Group A consisted of seven recipients whose new liver grafts started to consume lactate immediately after portal perfusion. Group B consisted of the remaining eight recipients whose intraoperative blood lactate values showed no change or an elevation for 2 hours after graft revascularization.

RESULTS

All Group A patients survived, whereas three out of eight patients in Group B died of infection and portal vein thrombosis within 3 months after LDLT. There was no significant difference in preoperative donor and recipient laboratory data. The recipient age and body size in Group B were significantly higher than those in Group A, indicating that Group B consisted of small-for-size liver transplant cases. Serum total bilirubin concentrations in Group B were significantly higher than Group A from postoperative day 5 to 23, whereas postoperative liver enzyme levels and prothrombin time were similar between the two groups.

CONCLUSION

The change in intraoperative blood lactate after hepatic allograft reperfusion served as an accurate predictor of initial graft function which was associated with graft size in human LDLT.

Expression of hepcidin is down-regulated in TfR2 mutant mice manifesting a phenotype of hereditary hemochromatosis

Transferrin receptor 2 (TfR2) is a membrane glycoprotein that mediates cellular iron uptake from holotransferrin. Homozygous mutations of this gene cause one form of hereditary hemochromatosis in humans. We recently reported that homozygous TfR2(Y245X) mutant mice, which correspond to the TfR2(Y250X) mutation in humans, showed a phenotype similar to hereditary hemochromatosis. In this study, we further analyzed the phenotype as well as iron-related gene expression in these mice by comparing the TfR2-mutant and wild-type siblings. Northern blot analyses showed that the levels of expression of hepcidin mRNA in the liver were generally lower, whereas those of duodenal DMT1, the main transporter for uptake of dietary iron, were higher in the TfR2-mutant mice as compared to the wild-type siblings. Expression of hepcidin mRNA in the TfR2 mutant mice remained low even after intraperitoneal iron loading. In isolated hepatocytes from both wild-type and TfR2 mutant mice, interleukin-6 and lipopolysaccharide each induced expression of hepcidin mRNA. These results suggest that up-regulation of hepcidin expression by inflammatory stimuli is independent of TfR2 and that TfR2 is upstream of hepcidin in the regulatory pathway of body iron homeostasis. (Blood. 2005;105:376-381)

Efficacy of cutting balloon for anastomotic stricture of the hepatic vein

Anastomotic stricture of the hepatic vein is an annoying complication, especially in living donor liver transplantation. Balloon dilation has been utilized but is sometimes associated with recurrences. Recently, a cutting balloon was invented for treatment of arteriosclerosis. Herein we report the results of application of this device for treatment of anastomotic strictures of the hepatic vein in two living donor liver transplant recipients who underwent percutaneous dilation of the hepatic vein with a cutting balloon (8 x 10 mm, Atherotome, Boston Scientific). Case 1, a 26-year-old woman transplanted for subacute fulminant hepatitis, had been treated for an anastomotic stricture by balloon dilation on 15 occasions over a 2- to 3-month interval. Case 2, a 13-year-old boy transplanted for cryptogenic liver cirrhosis, had been treated for an anastomotic stricture by balloon dilation biannually. The cutting balloon was applied safely without severe complications. The first case showed a recurrent anastomotic stricture at 6 months after dilation. Follow-up at 6 months in the second case revealed a mild recurrence of the stricture. Anastomotic stricture of the hepatic vein jeopardizes the graft and the recipient. The reported treatments involve venoplastic surgery and expandable metallic stents. Application of a cutting balloon seemed to be a safe, convenient modality. However, its effect was not indefinite, so a cutting balloon of greater diameter or application of an expandable metallic stent may be considered for patients with multiple recurrences of their anastomotic stricture.

Hepatic clearance improves after angioplasty of the hepatic vein

Anastomotic stricture sometimes causes hepatic congestion leading to decreased hepatic clearance of drugs. We herein describe a correlation between trough levels of tacrolimus and an anastomotic stricture of the hepatic vein. A 13-year-old boy underwent living donor liver transplant with a left lobe graft from his mother. Outflow blockage due to an anastomotic stricture of the hepatic vein developed 3 months after transplant. His anastomotic site had been repeatedly treated with percutaneous transvenous angioplasty (PTA) by balloon dilation. About 1 year after transplant, his trough level of tacrolimus promptly decreased after balloon dilation (from 15.7 to 5.6 ng/dL). Liver function tests showed abnormalities, which were diagnosed as acute cellular rejection, and he was treated with pulse steroid therapy. The calculated half-life of tacrolimus (T1/2) showed marked improvement after PTA (from 35 to 22 hours). A 45-year-old woman underwent living donor transplantation due to alcoholic liver cirrhosis with a left lobe graft from her brother. An anastomotic stricture of the hepatic vein developed 4 months after transplant. She was treated with balloon dilation, which caused an abrupt decrease in the trough level of tacrolimus (12 to 4 ng/dL). Her alkaline phosphatase was elevated and she was diagnosed with rejection, which was treated with an increase of dosage of tacrolimus. In outflow block, the T1/2 of tacrolimus increases probably due to decreased hepatic clearance by stagnation or congestion of the liver. However, hepatic clearance of drugs quickly recovers after PTA. Close monitoring of immunosuppressive agents is fundamental at the time of angioplasty to avoid acute cellular rejection as developed in our two cases.

A novel sub-population of bone marrow-derived myocardial stem cells: potential autologous cell therapy in myocardial infarction

BACKGROUND

Several studies have identified beta2-microglobulin-negative (beta2M(-)) cells as a potential stem cell fraction in the bone marrow of rats and humans. We studied the ability of bone marrow-derived beta2M(-) cells to differentiate into cardiomyocytes and reconstitute the myocardium in a model of myocardial infarction.

METHODS

beta2M(-) cells were purified from bone marrow of Lewis rats using a magnetic activated cell-sorting technique. beta2M(-) cells, 2.5 x 10(6) cells in 100 microl of phosphate-buffered saline (PBS), were transplanted 7 days after infarction into a transmural myocardial scar induced by cryoinjury in Lewis rats (n = 9). Control Group 1(n = 10) received a 100-microl injection of PBS, and Control Group 2 (n = 15) received no injection. The beta2M(-) cells were labeled before transplantation, using the membrane fluorescent intercalated dye, PKH26. Repopulation was examined at 6 and 8 weeks after transplantation. Differentiation of beta2M(-) cells into cardiac myocytes was determined by the colocalization of troponin and PKH26 to the same cell, utilizing immunohistochemistry, ultraviolet photomicroscopy and fluorescence microscopy on 6-microm serial sections. Area of engraftment within the scar was calculated by planimetry.

RESULTS

The treatment group had multiple islands of de novo-formed myocardium within the fibrous matrix of the transmural scar (mean area 35 +/- 4.2% of scar area at 6 and 8 weeks). These cells colocalized cardiac-specific troponin and PKH26. Using these techniques, no myocardial islands were seen in the control groups. Before transplantation, beta2M(-) cells were troponin-negative.

CONCLUSIONS

This study demonstrates that beta2M(-) cells represent a novel sub-population of bone marrow-derived stem cells capable of successful and substantial engraftment in areas of transmural myocardial scar, with de novo formation of cardiac myocytes. The functional significance of this observation is being studied.

Hepatic vein anastomotic stricture after living donor liver transplantation

This report discusses the pathophysiology of and therapeutic methods to address hepatic vein anastomotic stricture after living donor liver transplantation (LDLT). From 1994 to 2002, our 15 LDLTs using the lateral segments or left lobes included four recipients who experienced 28 occurrences of this complication after the operation. The period between LDLT and the first stricture was 4.0 +/- 1.2 months. The age of the affected recipients (31.0 +/- 8.2 years) was significantly higher than that of the nonaffected patients (7.0 +/- 4.1 years, P < .05). Graft liver/standard liver volume ratio was 39.1% +/- 3.8% in the former and 77.9% +/- 12.7% in the latter cases (P < .05). Initial symptoms of stricture were ascites (42.9%), abdominal distention (42.9%), liver enzyme elevation (10.7%), and gastrointestinal bleeding (3.6%). In addition, 14 of 28 stricture cases (50%) showed increased blood trough levels of tacrolimus. Doppler ultrasonography was used for diagnosis, and balloon dilatations performed in all stricture patients, thereby hepatic significantly reducing venous blood pressure from 33.5 +/- 1.7 to 20.3 +/- 1.5 cmH2O. All patients finally resolved the strictures after several treatments. The stricture after LDLT was associated with small-for-size grafts, suggesting that liver regeneration may lead to anatomical changes and strictures. Since tacrolimus is metabolized by the liver, its blood trough level is one initial symptoms of stricture. Balloon dilatation was useful and safe as the treatment, while problems have been reported after stent insertion in the hepatic vein.

Central and peripheral actions of somatostatin on the growth hormone-IGF-I axis

Somatostatin (SRIF) analogs provide safe and effective therapy for acromegaly. In a proportion of patients, however, SRIF analogs may lead to discordant growth hormone (GH) and IGF-I suppression, which suggests a more complex mechanism than attributable to inhibition of GH release alone. To elucidate whether SRIF acts peripherally on the GH-IGF-I axis, we showed that rat hepatocytes express somatostatin receptor subtypes-2 and -3 and that IGF-I mRNA and protein levels were suppressed in a dose-dependent manner by administration of octreotide. The inhibitory effect of SRIF was not apparent without added GH and in the presence of GH was specific for IGF-I induction and did not inhibit GH-induced c-myc or extracellular signal regulated kinase (ERK) phosphorylation. Pertussis toxin treatment of hepatocytes incubated with GH and SRIF, or with GH and octreotide, abrogated the inhibitory effect on GH-induced IGF-I, which confirms the requirement for the inhibitory G-protein. Treatment with SRIF and GH increased protein tyrosine phosphatase (PTP) activity and inhibited signal transducer and activator of transcription-5b (STAT5b) phosphorylation and nuclear localization. Octreotide also inhibited GH-stimulated IGF-I protein content of ex vivo-perfused rat livers. The results demonstrate that SRIF acts both centrally and peripherally to control the GH-IGF-I axis, providing a mechanistic explanation for SRIF analog action in treating patients with GH-secreting pituitary adenomas.

Intrasplenic transplantation of encapsulated cells: a novel approach to cell therapy

Cell therapy is likely to succeed clinically if cells survive at the transplantation site and are protected against immune rejection. We hypothesized that this could be achieved with intrasplenic transplantation of encapsulated cells because the cells would have instant access to oxygen and nutrients while being separated from the host immune system. In order to provide proof of the concept, primary rat hepatocytes and human hepatoblastoma-derived HepG2 cells were used as model cells. Rat hepatocytes were encapsulated in 100-kDa hollow fibers and cultured for up to 28 days. Rat spleens were implanted with hollow fibers that were either empty or contained I x 10(7) rat hepatocytes. Human HepG2 cells were encapsulated using alginate/ poly-L-lysine (ALP) and also transplanted into the spleen; control rats were transplanted with free HepG2 cells. Blood human albumin levels were measured using Western blotting and spleen sections were immunostained for albumin. Hepatocytes in monolayer cultures remained viable for only 6-10 days, whereas the cells cultured in hollow fibers remained viable and produced albumin throughout the study period. Allogeneic hepatocytes transplanted in hollow fibers remained viable for 4 weeks (end of study). Free HepG2 transplants lost viability and function after 7 days, whereas encapsulated HepG2 cells remained viable and secreted human albumin at all time points studied. ALP capsules, with or without xenogeneic HepG2 cells, produced no local fibrotic response. These data indicate that intrasplenic transplantation of encapsulated cells results in excellent survival and function of the transplanted cells and that the proposed technique has the potential to allow transplantation of allo- and xenogeneic cells (e.g., pancreatic islets) without immunosuppression.

Improved survival and ammonia metabolism by intraperitoneal transplantation of microencapsulated hepatocytes in totally hepatectomized rats

BACKGROUND

We evaluated the effects of intraperitoneal transplantation of microencapsulated hepatocytes in a 3-stage total hepatectomy rat model.

METHODS

A new model of total hepatectomy was created as follows. First, the infrahepatic inferior vena cava was ligated just above the right renal vein. Seven days later, the portal vein was ligated and a portacaval shunt was established using a Teflon catheter over a venipuncture needle. Another 7 days later, total hepatectomy was completed by ligating and dividing the suprahepatic inferior vena cava, the hepatic artery, and the bile duct. Next, 4 x 10(7) hepatocytes (4% of the normal liver hepatocyte mass) isolated from male Wistar rats were microencapsulated within a collagen matrix enveloped by a 3-layer membrane of sodium alginate-poly-L-lysine-sodium alginate copolymer. Capsules containing hepatocytes (diameter, 500-800 microm) and empty capsules (control) were transplanted intraperitoneally 4 days before the total hepatectomy. Survival time and selected blood chemistry concentrations after the total hepatectomy were measured. The capsules were also examined histologically with hematoxylin and eosin staining and modified Gmelin's stain for bile pigments.

RESULTS

The survival time was greater in the rats given the microencapsulated hepatocytes than in the control rats (17.3 +/- 3 vs 3.7 +/- 0.1 hours; P <.01). The blood ammonia concentrations increased soon after total hepatectomy but remained significantly lower in the rats with microencapsulated hepatocytes (P <.05). The microcapsules contained numerous viable hepatocytes with abundant bile pigments and no lymphocytic infiltration.

CONCLUSIONS

Microencapsulated hepatocytes with an ultrathin polymer layer that protects them from inflammatory and lymphocytic reactions may facilitate their ability to function. In this study, 4 x 10(7) hepatocytes significantly prolonged the survival of rats that underwent hepatectomy and supported ammonia metabolism. Further development of this technique may permit its use in patients with hepatic failure.

A physical map with yeast artificial chromosome (YAC) clones covering 63% of the 12 rice chromosomes

A new YAC (yeast artificial chromosome) physical map of the 12 rice chromosomes was constructed utilizing the latest molecular linkage map. The 1439 DNA markers on the rice genetic map selected a total of 1892 YACs from a YAC library. A total of 675 distinct YACs were assigned to specific chromosomal locations. In all chromosomes, 297 YAC contigs and 142 YAC islands were formed. The total physical length of these contigs and islands was estimated to 270 Mb which corresponds to approximately 63% of the entire rice genome (430 Mb). Because the physical length of each YAC contig has been measured, we could then estimate the physical distance between genetic markers more precisely than previously. In the course of constructing the new physical map, the DNA markers mapped at 0.0-cM intervals were ordered accurately and the presence of potentially duplicated regions among the chromosomes was detected. The physical map combined with the genetic map will form the basis for elucidation of the rice genome structure, map-based cloning of agronomically important genes, and genome sequencing.

Evolutionary aspects of gobioid fishes based upon a phylogenetic analysis of mitochondrial cytochrome B genes

The Gobioidei is a large suborder in the order Perciformes and consists of more than 2000 species belonging to about 270 genera. The vast number of species and their morphological specialization adapted to diverse habits and habitats makes the classification of the gobioid fishes very difficult.A comprehensive estimation of the evolutionary scenario of all gobioid fishes using only morphological information is difficult for two major reasons: first, in addition to wide ecological diversification, there is a trend towards specialization and degeneration of morphological characters among these species; second, an appropriate outgroup of gobioid fishes has not been recognized. Based upon nucleotide sequence comparisons of gobioid mitochondrial cytochrome b genes, we established the phylogenetic relationships of their differentiation into many groups of morphological and ecological diversity. The phylogenetic trees obtained show that most species examined have diverged from each other almost simultaneously or during an extremely short period of time.

Hd1, a major photoperiod sensitivity quantitative trait locus in rice, is closely related to the Arabidopsis flowering time gene CONSTANS

A major quantitative trait locus (QTL) controlling response to photoperiod, Hd1, was identified by means of a map-based cloning strategy. High-resolution mapping using 1505 segregants enabled us to define a genomic region of approximately 12 kb as a candidate for Hd1. Further analysis revealed that the Hd1 QTL corresponds to a gene that is a homolog of CONSTANS in Arabidopsis. Sequencing analysis revealed a 43-bp deletion in the first exon of the photoperiod sensitivity 1 (se1) mutant HS66 and a 433-bp insertion in the intron in mutant HS110. Se1 is allelic to the Hd1 QTL, as determined by analysis of two se1 mutants, HS66 and HS110. Genetic complementation analysis proved the function of the candidate gene. The amount of Hd1 mRNA was not greatly affected by a change in length of the photoperiod. We suggest that Hd1 functions in the promotion of heading under short-day conditions and in inhibition under long-day conditions.

Hd1, a major photoperiod sensitivity quantitative trait locus in rice, is closely related to the Arabidopsis flowering time gene CONSTANS

A major quantitative trait locus (QTL) controlling response to photoperiod, Hd1, was identified by means of a map-based cloning strategy. High-resolution mapping using 1505 segregants enabled us to define a genomic region of approximately 12 kb as a candidate for Hd1. Further analysis revealed that the Hd1 QTL corresponds to a gene that is a homolog of CONSTANS in Arabidopsis. Sequencing analysis revealed a 43-bp deletion in the first exon of the photoperiod sensitivity 1 (se1) mutant HS66 and a 433-bp insertion in the intron in mutant HS110. Se1 is allelic to the Hd1 QTL, as determined by analysis of two se1 mutants, HS66 and HS110. Genetic complementation analysis proved the function of the candidate gene. The amount of Hd1 mRNA was not greatly affected by a change in length of the photoperiod. We suggest that Hd1 functions in the promotion of heading under short-day conditions and in inhibition under long-day conditions.