Search PubMed⌕ Search

Biomedical subjects

N Nakajima

Publications and source records attributed to N Nakajima.

At least 127 records · Page 7Linked to original sources
PubMed1999

Aggressive surgical resection for hepatic metastases involving the inferior vena cava.

BACKGROUND: The implications of aggressive surgical approaches for hepatic metastases involving the inferior vena cava (IVC) have not been clarified yet. The aim of this study is to assess the preliminary results of aggressive surgical resection for hepatic metastases involving the IVC. METHODS: Sixteen patients with hepatic metastases involving the IVC underwent surgical resections with the repair and reconstruction of the IVC: patch repair in 2 and ringed Goretex in 1, primary closure in 13 patients. Hepatic metastases were from colorectal cancer in 14, stomach cancer in 1, and uterine cancer in 1 patient. RESULTS: Vascular control utilized for resecting the IVC were total hepatic vascular exclusion in 8, hypothermic isolated hepatic perfusion in 3, and side clamp in 5 patients. The combined IVC resection with hepatectomy in 16 patients brought about 25% and 6% surgical morbidity and mortality rates, respectively. Survival rates following surgical resections were 64%, 33%, 33%, 22%, 22% for 14 patients of colorectal metastases involving the IVC as compared with 82%, 58%, 41%, 37%, 27% at 1, 2, 3, 4, 5 years, respectively, for 154 patients of colorectal metastases not involving the IVC. CONCLUSION: Hepatic metastases involving the IVC could be safely resected without an increase in surgical risk. Aggressive surgical approaches might bring about a favorable outcome in select patients with colorectal hepatic metastases involving the IVC.

Adult↗
PubMed1999

Changes in hepatic venous oxygen saturation related to the extent of regeneration after partial hepatectomy in rats.

BACKGROUND: Changes in hepatic oxygen metabolism in relation to the extent of liver regeneration are expected after partial hepatectomy. There are few reports, however, about hepatic oxygen metabolism during liver regeneration. In this study, we evaluated changes in hepatic oxygen metabolism related to the regeneration rate, and the relationship between hepatic venous oxygen saturation (Shvo2) and liver regeneration after partial hepatectomy. METHODS: The work was done using 50% hepatectomized rats with continuous infusion of octreotide for inhibition of liver regeneration or with saline as control. The hepatic hemodynamics, oxygen metabolism, and Shvo2 levels as well as the regenerating liver status were evaluated for 3 days after hepatectomy. RESULTS: Administration of octreotide resulted in a significant reduction of the regenerating liver weight on days 1 and 3 after hepatectomy compared with the control group. Significantly decreased DNA synthesis and proliferating cell nuclear antigen labeling index were also found on day 1. Meanwhile, hepatic oxygen consumption (HVO2) and oxygen extraction ratio were significantly decreased in the octreotide-treated group on day 1. In contrast, the Shvo2 levels in the octreotide-treated group were significantly higher than those in the control group, and were inversely correlated with the HVO2. CONCLUSION: The remnant liver demands an increased amount of oxygen in relation to the extent of regeneration, and changes in the Shvo2 are inversely correlated with the HVo2. Therefore, monitoring the Shvo2 could be useful for estimating liver regeneration after partial hepatectomy.

Animals↗
PubMed1999

Predictive factors for mortality and cerebral complications in arteriosclerotic aneurysm of the aortic arch.

BACKGROUND: The incidence of cerebral complications is high in patients with aortic arch aneurysm. METHODS: Between December 1977 and December 1995, 246 patients with arteriosclerotic arch aneurysm underwent operation. Thirty-nine patients had an aneurysm involving the entire arch, 193 had only distal arch aneurysm, and 14 had arch aneurysm extending to the descending aorta. Eighty-seven patients underwent replacement of the total arch, 85 had replacement of only the distal arch, 14 had simultaneous replacement of the descending aorta, 45 had patch repair, and 15 had thromboexclusion. Selective cerebral perfusion was used in 112 patients and partial bypass in 58 in the earlier series of patients, but deep hypothermic circulatory arrest with retrograde cerebral perfusion technique was exclusively applied in the most recent 76 patients. RESULTS: There were 50 (20%) early deaths and 37 (19%) late deaths. Postoperative stroke was found in 26 (11%) patients of which 13 (50%) died. Mutual predictive factors for postoperative mortality and stroke were earlier series, preoperative chronic renal failure, ruptured aneurysm, arch clamping during procedure, and using partial cardiopulmonary bypass. Among 129 patients operated on during the most recent 5 years, early mortality and incidence of stroke decreased to 14.7% and 6.9%, respectively. CONCLUSIONS: Results of operations for arteriosclerotic aneurysms of the transverse aortic arch in 246 patients during a period of 17 years have been improving but are still not satisfactory.

Adult↗
PubMed1999

A new method for the treatment of graft infection in the thoracic aorta: in situ preservation.

BACKGROUND: We have developed a new method to control graft infection by a combination of two procedures, extensive disinfection followed by tissue flap implantation, allowing preservation of the original graft. METHOD: Soon after the diagnosis of graft infection was confirmed, the wound was re-explored, and debridement, irrigation and packing with sponges soaked with 10% iodine solution were employed. This procedure was repeated every 8 hours for the first 48 hours. For the second step, tissue flaps using omentum or muscle were implanted around the graft as well as in dead space, and the wound was closed primarily. MATERIALS: A total of 6 patients were treated: 4 in the acute and 2 in the chronic phase of infection. The original procedures were a Bentall procedure + arch replacement (1), ascending aorta replacement + arch (3) and replacement of the descending aorta (2). In descending aorta cases, an extended thoracoplasty was concomitantly added to eliminate dead space in the pleural cavity. RESULTS: Graft infections were controlled in all 6 patients. One hospital death unrelated to infection was encountered. Five patients were discharged, but 1 died of a stent-graft complication. The follow-up period ranged from 4 months to 10 years. CONCLUSION: Our method of extensive disinfection followed by tissue flap coverage of the graft proved to be highly effective in controlling the serious complication of graft infection associated with surgery of the thoracic aorta.

Adult↗
PubMed1999

Is distal anastomosis only to the true channel in chronic type B aortic dissection justified?

BACKGROUND: We investigated long-term outcomes of the distal false lumen of the aorta and aortic branches after distal anastomosis of the graft only to the true lumen in chronic type B aortic dissection. METHODS: From November 1979 until June 1998, we treated 98 patients without Marfan syndrome who had chronic type B aortic dissection and underwent replacement of the descending aorta, 79 of whom had distal anastomosis to the true lumen only. The celiac artery originated from the false lumen in 11 patients, superior mesenteric artery in 5, right renal artery in 19, and left renal artery in 16. RESULTS: There were 12 (15.1%) early deaths. Spinal cord ischemia was detected in 5 patients. Postoperative follow-up was achieved in 67 patients, and 13 patients died. Postoperative survival at 10 years was 67.6% +/- 7.1%. Eight patients had complete occlusion of the distal false lumen, 54 patients had occlusion of the false lumen down to the celiac artery, and 5 patients had a patent false lumen. Four patients required further replacement of the thoracoabdominal aorta. CONCLUSIONS: In non-Marfan patients with chronic type B aortic dissection, the false lumen distal to the graft anastomosis was likely to be thrombosed when the graft was anastomosed to the true lumen only. Postoperative visceral circulation was not compromised, but spinal cord ischemia is a problem that remains to be solved.

Adult↗
PubMed1999

Application of the hybridization AT-tailing method for detection of human immunodeficiency virus RNA in cells and simian immunodeficiency virus RNA in formalin-fixed and paraffin-embedded tissues.

An in situ hybridization (ISH) AT-tailing method (HybrAT) was developed for the detection of viral genomes in infected cells and tissues. The method consists of hybridization with oligonucleotide probe which has a 3' end oligo d(A-T) tag, followed by elongation of the oligo d(A-T) by deltaTth DNA polymerase in the presence of the labeled nucleotide. The in situ HybrAT detected human immunodeficiency virus type 1 (HIV-1) in cells and simian immunodeficiency virus (SIV) in formalin-fixed and paraffin embedded sections with a sensitivity comparable to RNA ISH. The advantage of this method over other methods is discussed.

Animals↗
PubMed1999

Effect of intravenous omega-6 and omega-3 fat emulsions on nitrogen retention and protein kinetics in burned rats.

The effect of omega-3 fat emulsion on nitrogen retention and kinetics in relation to fatty acid profile were investigated in burned rats receiving total parenteral nutrition (TPN). A fat emulsion of a structured symmetrical triacylglycerol containing only eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (2:1) was prepared. Sprague-Dawley rats were fed by fat-free chow for 2 wk. Then rats were fed exclusively with one of three types of TPN for 7 d. Animals in group C received fat-free TPN (n = 11). Group omega 6 received safflower oil fat emulsion, which accounted for 20% of total caloric intake (n = 11). Group omega 3 received fat emulsion containing only EPA and DHA (1% of total calories, n = 11), in addition to safflower oil emulsion (19% of total calories). On day 5, each rat was subjected to 20% full-thickness scald burns. Rats were sacrificed under ether anesthesia 48 h after burning. The rats in group C became deficient in omega-6 essential fatty acids. Cumulative nitrogen balance was decreased significantly in group omega 6. The rates of whole-body protein synthesis were increased significantly in both groups omega 6 and omega 3. In omega 6, however, the rates of whole-body protein breakdown were increased significantly. In conclusion, the rates of whole-body protein breakdown increased and nitrogen retention was aggravated significantly in animals administered the safflower oil emulsion. Significant increases of urinary excretion of total catecholamine were also observed. Prostaglandin E2 and thromboxane B2 concentrations were not significantly different among three groups. Supplementation with the new omega-3 fat emulsion, however, improved protein metabolism in burned rats receiving TPN.

Animals↗
PubMed1999

Changes in immune function following surgery for esophageal carcinoma.

Changes in immune function due to surgical injury have been well-documented. Immunosuppression is one of the causes of infectious complications leading to organ dysfunction in critical illness. It is not known what kind of surgery in the daily clinical practice causes immunosuppression. Stress response and immune function following surgery for esophageal carcinoma, assuming a highly-stressed operation, were studied and then compared with the stress response and immune function following gastric surgery, a moderately-stressed procedure. Forty patients who underwent esophagectomy and 39 patients receiving gastric operation were studied. The concentrations of serum interleukin-6 (IL-6) were measured preoperatively, at 1, 2, and 6 h, and at 1, 3, and 10 d after operation. Total protein, serum albumin, rapid turnover protein, serum CRP, and cortisol were measured before operation and at 1, 3, 7, and 21 d after operation. ConA- and PHA-stimulated lymphocyte proliferation, IgA, IgG, and IgM were also measured preoperatively, and on 7 and 21 d following surgery. The patients were fed exclusively by total parenteral nutrition (TPN). A striking rise of IL-6 was observed, with a peak in both groups at 1 to 6 h following operation. The peak values were 419+/-30 pg/mL, which was approximately twice as high in the esophagectomy patients as in the gastrectomy patients (195+/-40 pg/mL). CRP and cortisol also increased after operation, and these increases were also significantly greater in the esophagectomy patients. ConA- and PHA-stimulated lymphocyte proliferation decreased significantly 7 d after esophagectomy (P<0.05), but was unchanged in the patients receiving gastrectomy. Suppression of cellular immunity correlated significantly with serum cortisol, and was preceded by a rise in serum IL-6. The IgA, IgG, and IgM levels, however, remained unchanged from their preoperative values throughout the study in both groups. Nutritional status in terms of serum protein, albumin, and rapid turnover protein, decreased postoperatively, but there was no difference between the two groups. It is, therefore, concluded that cell-mediated immunosuppression, preceded by a hyperinflammatory response, is an observable reaction in patients following esophageal surgery, but not in patients undergoing gastric surgery.

Aged↗
PubMed1999

Parenchyma-preserving hepatectomy in the surgical treatment of hilar cholangiocarcinoma.

BACKGROUND: Although extended hepatic resection has been shown to improve prognosis by increasing the surgical curability rate in hilar cholangiocarcinoma, high surgical morbidity and mortality rates have been reported in patients with obstructive jaundice. Postoperative liver failure after hepatic resection in patients with obstructive jaundice has been shown to depend on the volume of the resected hepatic mass. The aim of this study was to evaluate the results of parenchyma-preserving hepatectomy in a surgical treatment for hilar cholangiocarcinoma. STUDY DESIGN: Ninety-three resected patients with hilar cholangiocarcinoma were included in this retrospective study. The resected patients were stratified into three groups: the extended hepatectomy (EXH) group (n = 66), the parenchyma-preserving hepatectomy (PPH) group (n = 14), and the local resection (LR) group (n = 13). The EXH group had undergone hepatectomy more extensive than hemihepatectomy, the PPH group had undergone hepatectomy less extensive than hemihepatectomy, and the LR group had undergone extrahepatic bile duct resection without hepatic resection. Surgical curability, defined by histologically confirmed negative surgical margins, surgical morbidity and mortality, and survival rates were compared among the three groups. The clinicopathologic factors were studied for prognostic value by univariate and multivariate analyses. RESULTS: Surgical curability of the PPH and EXH groups was better than that of the LR group. Fifty-four percent of patients in the LR group showed positive surgical margins at the hepatic stump of the bile duct, compared with 7% in the PPH group and 20% in the EXH groups (p < 0.01 for each comparison). Surgical morbidity was higher in the EXH group (48%) than in the LR group (8%) and the PPH group (14%) (p < 0.01 and p < 0.05, respectively). Postoperative hyperbilirubinemia occurred more frequently in the EXH group (29%) than in the LR and PPH groups (0% and 0%, respectively, p < 0.05 for each comparison). Survival rates after resection were significantly higher in patients who underwent hepatectomy, including PPH and EXH, than in patients who underwent LR, 29% versus 8% at 5 years, respectively (p < 0.05). But no significant difference in survival was found between the PPH and EXH groups. Univariate and multivariate analyses showed that significant prognostic factors for survival were resected margin, lymph nodal status, and vascular resection. CONCLUSIONS: In conclusion, PPH could obtain a curative resection and improve the outcomes for patients with hilar cholangiocarcinoma that is localized at the hepatic duct confluence who do not require vascular resection. PPH might bring about a beneficial effect in highly selected patients according to extent of cancer and high-risk patients with liver dysfunction.

Bile Duct Neoplasms↗
PubMed1999

Degradation of pectic substances by two pectate lyases from a human intestinal bacterium, Clostridium butyricum-beijerinckii group.

Clostridium butyricum-beijerinckii group, an anaerobic human intestinal bacterium, produced exo-pectate lyase, endo-pectate lyase, and pectin methylesterase, but not polygalacturonase. The production of the two pectate lyases was strongly influenced by the composition of the carbon sources added to the medium. The enzymes secreted by the bacterium into the human large intestine cooperatively digested pectic substances, producing mainly 4,5-unsaturated digalacturonic acid with the participation of the pectin methylesterase. The findings suggest that in the human intestine the bacterium contributes to the digestion of ingested pectic substances.

Journal Article↗
PubMed1999

Lipase-catalyzed direct and regioselective acylation of flavonoid glucoside for mechanistic investigation of stable plant pigments.

One-step and regioselective acylation of flavonoid glucosides was achieved by lipase-catalyzed transesterification in dry organic media. For example, isoquercitrin (quercetin 3-O-glucoside), one of the flavonol monoglucosides, was converted efficiently to the corresponding aromatic acid ester (isoquercitrin 6''-O-cinnamate) by a lipase with vinyl cinnamate as an acyl donor. The method described, which is the first allowing the direct synthesis of aromatic acid esters of flavonoid glucosides, can be applied to the acylation of other glucosides, including naringin, rutin, callistephin, and chrysanthemin.

Journal Article↗
PubMed1999

Adjuvant regional chemotherapy after hepatic resection for colorectal metastases.

BACKGROUND: This study explored the possibility of achieving a better survival rate and reduced recurrence in the remaining liver in patients with colorectal hepatic metastases undergoing hepatic resection. Adjuvant postoperative regional chemotherapy was administered via the hepatic artery or the portal vein. METHODS: A retrospective study was performed on 174 patients after hepatic resection for colorectal metastases. These comprised 78 patients who had hepatic artery infusion (HAI) chemotherapy (HAI group), 30 who had portal vein infusion (PVI) chemotherapy (PVI group) and 66 who had no regional chemotherapy (resection alone group). The three groups were compared with one another in terms of complications, survival rate and patterns of recurrence. RESULTS: Severe complications did not occur at any point during adjuvant HAI or PVI chemotherapy. The 5-year disease-free survival rate of patients in the HAI, PVI and resection alone groups were 35, 13 and 9 per cent respectively, including six hospital deaths. Patients in the HAI group showed significantly improved recurrence rates in the remaining liver compared with the resection alone group (P = 0.03), and more prolonged disease-free and overall survival than those in the PVI (P = 0.01 and P = 0.02 respectively) and resection alone (P = 0.0001 and P = 0.0006 respectively) groups. CONCLUSION: This study suggests that adjuvant HAI chemotherapy after hepatic resection may have therapeutic potential for improved management of patients with colorectal metastases.

Aclarubicin↗
PubMed1999

Clinical assessment of positron emission tomography for the diagnosis of local recurrence in colorectal cancer.

BACKGROUND: The clinical value of positron emission tomography (PET) for the diagnosis of local pelvic recurrence of colorectal cancer was evaluated. METHODS: Computed tomography (CT) and magnetic resonance imaging (MRI) of the pelvis were performed at regular intervals in 23 patients who had undergone resection for colorectal cancer. The 23 patients had a total of 25 lesions. PET images of the 25 lesions and of six primary lesions in patients with rectal cancer were obtained. A differential absorption ratio (DAR) was calculated in order to examine the accumulation of [18F]2-fluoro-2-deoxy-D-glucose (18FDG) on PET images. Histological diagnoses of the pelvic masses were obtained by CT-guided needle biopsy. RESULTS: On CT or MRI, a pelvic mass with a spicular shape (n = 1) was non-recurrent, whereas a nodular or lumpy shape indicated a locally recurrent lesion (n = 10). Masses with a nodulospicular shape (n = 12) did not correlate with the histological features. On PET, 15 of 16 histologically proven local recurrences were imaged positively. By setting a DAR of 2.8 as a cut-off value, local recurrences could be diagnosed with 100 per cent accuracy. CONCLUSION: PET is a clinically useful tool for the detection of local recurrence of colorectal cancer, particularly for distinguishing between recurrence and granulation tissues in the pelvic cavity.

Adult↗
PubMed1999

Efficacy of an implanted drug delivery system for advanced hepatocellular carcinoma using 5-fluorouracil, epirubicin and mitomycin C.

BACKGROUND: In order to assess the efficacy of repeated hepatic arterial infusion (HAI) therapy for advanced hepatocellular carcinoma, we administered HAI therapy using 5-fluorouracil, epirubicin and mitomycin C, with an implanted drug delivery system. METHODS AND RESULTS: Thirty-seven patients received HAI therapy with a response rate of 21.6%. The 6-month and 1-year survival rates were 67.6 and 29.7%, respectively. Responders to HAI therapy showed significantly longer survival than non-responders, while patients with mild liver dysfunction tended to survive longer than those with severe dysfunction. Neither tumour thrombosis of the main trunk of the portal vein nor extrahepatic metastases were considered to constitute contraindications for HAI therapy. Catheter-related trouble occurred in eight patients and biloma in one patient, but other side effects were transient and tolerable. These patients received HAI therapy as outpatients for an average of 79.6% of the entire course of therapy. CONCLUSIONS: Hepatic arterial infusion therapy proved effective for patients with advanced hepatocellular carcinoma in terms of improving survival and outpatient rates.

Adult↗
PubMed1999

Effective hepatic artery chemoembolization for advanced hepatocellular carcinoma with extensive tumour thrombus through the hepatic vein.

BACKGROUND AND AIMS: Advanced hepatocellular carcinoma (HCC) with extensive tumour growth through the hepatic vein still has an extremely poor prognosis, even after cancer chemotherapy and/or transarterial embolization. Although aggressive surgical treatments using extracorporeal circulation and liver transplantation have been performed by some authors, the reported results were still unsatisfactory. In this study, we report the favourable result of hepatic artery chemoembolization and subsequent surgical resection in three patients with advanced HCC with extensive tumour thrombus through the hepatic vein. METHODS AND RESULTS: Three irresectable patients with HCC with extensive tumour thrombus through the hepatic vein underwent hepatic artery chemoembolization with aclarubicin, mitomycin C, lipiodol and/or Gelfoam. After the reduction of tumour extent with hepatic artery chemoembolization, two of the three patients underwent surgical resection. These two patients are still alive at 59 and 21 postoperative months, respectively. In the other case, the extent of the tumour and functional reserve of the liver prevented us from performing surgical resection, but the patient is doing well 62 months after the initial treatment. CONCLUSIONS: Hepatic artery chemoembolization with aclarubicin, mitomycin C, lipiodol and/or Gelfoam might be an effective treatment for irresectable advanced HCC with extensive tumour thrombus into the inferior vena cava or the right atrium through the hepatic vein. Radical surgical resection might be applicable for selected patients without high surgical risk after reducing tumour extent by hepatic artery chemoembolization.

Aclarubicin↗
PubMed1999

Lobular involvement: prognostic indicator for invasive ductal carcinoma of the breast.

One of the striking microscopic appearances of breast carcinoma is malignant transformation of the epithelium of an entire lobule, although the lobular architecture is still preserved. We termed this pathological feature 'lobular involvement'. An investigation was carried out to determine whether lobular involvement would be a useful prognostic indicator for invasive ductal carcinoma. One hundred and fifty cases of invasive ductal carcinoma were included in this study. The lobular involvement, as well as the conventional prognostic factors, was evaluated to find out the correlation with the overall and relapse-free survivals by univariate and multivariate analyses. The lobular involvement was identified in 31 of 150 patients (20.6%). Of the patients with lobular involvement, two had experienced recurrence (6.5%) and one had died (3.2%). The lobular involvement and lymph node metastases were significantly and independently correlated with the overall and relapse-free survivals. The presence of lobular involvement was statistically correlated with the favorable outcome. Lobular involvement can be assumed as a new prognostic indicator for invasive ductal carcinoma.

Adult↗
PubMed1999

Subcellular localization of glucocorticoid receptor protein in the human kidney glomerulus.

BACKGROUND: The detailed mechanisms of glucocorticoid action in idiopathic nephrotic syndrome and progressive glomerulonephritides have not been clearly elucidated. The pharmacological actions of glucocorticoids are mediated by their binding to an intracellular protein, the glucocorticoid receptor (GR). The determination of GR localization in normal glomerular cells is essential to elucidate the mechanisms of glucocorticoid action in various glomerular diseases. METHODS: We carried out an immunoblot examination using antihuman GR-specific antibody and homogenates of isolated normal human glomeruli and mesangial cells in culture. Immunohistochemical examinations were also performed on normal human kidney specimens at light and electron microscopic levels. The nuclear translocation of GRs elicited by ligand binding was further investigated by confocal laser-scanning microscopic inspection of freshly isolated glomeruli and mesangial cells cultured with dexamethasone. RESULTS: An immunoblot examination demonstrated the presence of a 94 kDa protein, a molecular weight consistent with that of GRs, in the homogenates of glomeruli and cultured mesangial cells. By light microscopic examination, GRs were strongly detected in the nucleus and moderately in the cytoplasm of all glomerular cells, parietal and visceral epithelial cells, endothelial cells, and mesangial cells. By electron microscopic examination, the nuclear GRs of all glomerular cells were found to be diffusely distributed in the euchromatin. Additionally, the immunofluorescence intensities of nuclear GRs in isolated glomeruli and mesangial cells in culture became more intense by the addition of dexamethasone. CONCLUSIONS: Our findings suggest that all subsets of human glomerular cells definitely express the GR protein, which potentially undergoes translocation by glucocorticoids.

Cell Nucleus↗