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N Baba

Publications and source records attributed to N Baba.

At least 217 records · Page 12Linked to original sources

Role of anaerobic metabolism in the preservation of functional capacity and structure of anoxic myocardium.

Employing an isolated perfused rat heart preparation, we investigated the contribution of anaerobic metabolic energy to the performance, recoverability, and ultrastructure of the heart perfused at 32 degrees C in 5% albumin in Krebs-Ringer Bicarbonate solution. During exposure to anoxia for 30 min, inclusion in the perfusate of the anaerobic substrate, glucose, resulted in marked improvement in electrical and mechanical performance of the heart and in enhanced recovery during the subsequent period of reoxygenation. Lactate production was fivefold greater in the glucose-supported anoxic heart than in the anoxic heart without glucose. Electron microscope sections of the hearts exposed to anoxia in the absence of glucose revealed alterations in mitochondrial morphology and dilatation of the longitudinal tubules. These morphologic changes during anoxia were averted by inclusion of glucose in the perfusion fluid. The data are consistent with the hypothesis that anaerobic energy generation plays a significant role in preserving myocardial function and structure and in promoting recoverability of the anoxic mammalian heart.

Animals↗

Factors influencing prognosis and indications for curative pancreatectomy for ductal adenocarcinoma of the head of the pancreas.

The factors influencing prognosis and the indications for curative resection by radical pancreatectomy were evaluated in 74 patients treated with pancreatectomy for ductal cell carcinoma of the head of the pancreas. The 5-yr survival rates for patients without lymph node metastasis, capsular invasion, portal system involvement, or retroperitoneal invasion were 21.2, 20.2, 25.5, and 19.6%, respectively; the 5-yr survival rate for patients with lymph node metastasis or capsular invasion was 5.3% and 6.4%, respectively, and the 2-yr survival rate for patients with portal system involvement or retroperitoneal invasion was 0%. The 5-yr survival rate for 32 patients treated with radical pancreatectomy was 33.4%, and the 3-yr survival rate for 42 patients treated with nonradical pancreatectomy was 0%. Our results suggest that, in patients with ductal adenocarcinoma of the pancreas without factors limiting prognosis, curative resection by radical pancreatectomy is feasible; however, in patients with positive factors, particularly portal system involvement or retroperitoneal invasion, a comprehensive therapeutic program combining extensive surgery, radiation, chemotherapy and/or immunotherapy is necessary to obtain better results.

Adult↗

Ileo-caecal resection induced pancreatic growth in rats.

The effect of ileo-caecal resection on pancreatic growth was studied in rats four weeks after the operation. The results were compared with an identical control group who had undergone laparotomy alone. Pancreatic wet weight in ileo-caecal resectioned rats was 1.4 times greater than that found in control rats. Protein, DNA, RNA contents in the pancreas, pancreatic wet weight per 100 micrograms DNA and RNA/DNA ratio were also found significantly elevated in experimental group as opposed to the control group. Basal plasma levels of cholecystokinin (CCK) and gastrin were measured to delineate the influence of hormonal response on the pancreatic growth in ileo-caecal resected rats and were found not significantly increased after ileo-caecal resection. The data suggest that the enlargement of pancreas in ileo-caecal resected rats may be due to hyperplasia and hypertrophy of pancreatic cells; alternatively, the pancreatic growth may have been influenced by the bile acid deficiency and the reduction or release of an inhibitory factor present in the ileum of rats.

Aging↗

Preparation of heat-labile antigens on air-dried cytologic specimens for immunocytochemical analysis.

OBJECTIVE: To demonstrate the efficacy of Zamboni's solution and storage medium for immunocytochemistry of Ki-67, p53 tumor suppressor gene product and CD3 on long-preserved, air-dried cytologic specimens. STUDY DESIGN: Air-dried imprint cytologic specimens obtained from 13 lymphatic tissues and 13 colorectal cancers were fixed with Zamboni's solution and stored for various periods in storage medium including 50% glycerol at -10 to -20 degree C. Mouse monoclonal antibody PC, PAb 1801 and anti-Leu-4 were used for immunostaining. RESULTS: Immunocytochemical identification of Ki-67, p53 and CD3 was possible on specimens stored for 36, 32 and 16 weeks, respectively. CONCLUSION: Our method, using Zamboni's solution and storage medium, is feasible for immunocytochemistry on long-preserved, air-dried cytologic specimens using the three antibodies were employed.

Air↗

Antinematodal activity of some tropical rainforest plants against the pinewood nematode, Bursaphelenchus xylophilus.

Sixty five methanolic extracts of Sumatran rainforest plants representing 63 species of 21 families were assayed in vivo for antinematodal activity against Bursaphelenchus xylophilus using our cotton ball-fungal mat method. Extracts of 27 plants species from 14 families exhibited antinematodal activity, while 37 species were inactive. Among them, three extracts of Bischofia javanica, Knema hookeriana and Areca catechu exhibited very strong activity at minimum effective dose (MED) of 0.7 mg/cotton ball (mg/bl.). Eight extracts from Allamanda cathartica, Ervatamia corymbosa, Hoya diversifolia, Bischofia javanica, Derris malacensis, Melastoma melabathricum, Ophiorriza konsteleary and Brucea sumatrana also showed strong activity (MED, 5 mg/bl.).

Animals↗

Two antinematodal phenolics from Knema hookeriana, a Sumatran rainforest plant.

The activity-guided chromatographic purification of the methanol extract of Knema hookeriana, using pine wood nematodes Bursaphelenchus xylophilus has successfully led to the isolation and characterization of two phenolic antinematodal compounds with minimum effective dose (MED) of 4.5 and 20 microg/cotton ball (microg/bl.) or 0.018 and 0.073 microM/cotton ball (microM/bl.), respectively. Based on their chemical and spectral properties, these compounds were determined to be 3-undecylphenol (1) and 3-(8Z-tridecenyl)-phenol (2). These compounds were isolated for the first time from this species, and 2 seems to be a novel compound.

Animals↗

Crescentic glomerulonephritis associated with renal amyloidosis.

A case of crescentic glomerulonephritis associated with renal amyloidosis is reported. A 62-year-old woman with a 6-yr history of rheumatoid arthritis developed rapidly progressive glomerulonephritis associated with renal amyloidosis and crescent formation. Amyloid protein was positively stained with anti-AA antibody and its fibrils were demonstrated by electron microscopy. In connection with epithelial cell proliferation in the capsular space, destruction of the capillary basement membrane was observed at the sites where amyloid fibrils were accumulated, whereas glomerular deposition of immunoglobulin and complement was not detected. It is conceivable that the destruction of the glomerular tufts induced by amyloid deposition may be responsible for the crescent formation.

Amyloidosis↗

Combined treatment using radiotherapy for carcinoma of the pancreas involving the adjacent vessels.

The prognosis of pancreatic duct carcinoma is determined mainly by the degree of local invasion, particularly of the portal system and/or associated arteries supplying the carcinoma. Intraoperative (25-36.5 Gy of betatron) and/or external (14.4-25.6 Gy, preoperatively, and 24-61.2 Gy, postoperatively, using lineac photon beams) radiotherapy was combined with pancreatectomy or by-pass surgery for patients with pancreatic carcinoma involving the surrounding vessels but with no distant metastases. Twelve- and 24-month survival rates were 25.9% and 3.2%, respectively, in patients with pancreatectomy (n = 35) and 6.4% and 0%, respectively, in patients with by-pass operations (n = 32). However, in patients with combined surgery and radiotherapy the prognosis was markedly improved to 12- and 24-month survival rates of 33.5% and 20.1%, respectively, for patients with pancreatectomy (n = 13) and rates of 25% and 13%, respectively, for patients with by-pass operations (n = 8). Moreover, radiotherapy produced a significant advantage for local control of pain in patients with unresectable pancreatic carcinoma. This suggests that combined treatment using radiotherapy will be a valuable therapeutic improvement for patients presenting advanced pancreatic carcinoma with vessel involvement.

Carcinoma, Intraductal, Noninfiltrating↗

Human myocardial morphologic and functional changes in the first 24 hours after doxorubicin administration.

The purpose of this study was to document early structural changes in the human heart after the initial administration of doxorubicin. Endomyocardial biopsies were performed at baseline and at 4 and 24 hours after doxorubicin administration to 13 patients. Morphometric analysis of electron micrographs (x 31,200) quantitated mitochondrial and tubular sizes (sarcoplasmic reticulum and T tubules). The mitochondrial size increased from 0.25 +/- 0.01 mu 2 (mean +/- SE) at baseline to 0.27 +/- 0.03 mu 2 (not significant [NS]) at 4 hours and 0.30 +/- 0.03 mu 2 (NS) at 24 hours. The tubular size increased from 2.24 +/- 0.13 x 10(4) nm2 at baseline to 2.60 +/- 0.26 x 10(4) nm2 (P less than 0.05) at 4 hours and 2.46 +/- 0.29 x 10(4) nm2 (NS) at 24 hours. Micrographs analyzed for nuclear changes showed nucleolar contraction and segregation of granular and fibrillar components. These changes were noted in five of ten patients at 4 hours and in eight of 13 patients at 24 hours. Serial echocardiographic and systolic time interval determinations of left ventricular function demonstrated a significant improvement at both 4 and 24 hours. In conclusion, doxorubicin has its most significant effect on tubular structures. Left ventricular function improved during this time despite these findings.

Adult↗