Effects of Aerobic Growth on the Fatty Acid and Hydrocarbon Compositions of Geobacter bemidjiensis BemT.

Geobacter spp., regarded as strict anaerobes, have been reported to grow under aerobic conditions. To elucidate the role of fatty acids in aerobiosis of Geobacter spp., we studied the effect of aerobiosis on fatty acid composition and turnover in G. bemidjiensis BemT. G. bemidjiensis BemT was grown under the following different culture conditions: anaerobic culture for 4 days (type 1) and type 1 culture followed by 2-day anaerobic (type 2) or aerobic culture (anaerobic-to-aerobic shift; type 3). The mean cell weight of the type 3 culture was approximately 2.5-fold greater than that of type 1 and 2 cultures. The fatty acid methyl ester and hydrocarbon fraction contained hexadecanoic (16:0), 9-cis-hexadecenoic [16:1(9c)], tetradecanoic (14:0), tetradecenoic [14:1(7c)] acids, hentriacontanonaene, and hopanoids, but not long-chain polyunsaturated fatty acids. The type 3 culture contained higher levels of 14:0 and 14:1(7c) and lower levels of 16:0 and 16:1(9c) compared with type 1 and 2 cultures. The weight ratio of extracted lipid per dry cell was lower in the type 3 culture than in the type 1 and 2 cultures. We concluded that anaerobically-grown G. bemidjiensis BemT followed by aerobiosis were enhanced in growth, fatty acid turnover, and de novo fatty acid synthesis.

Bacterial Long-Chain Polyunsaturated Fatty Acids: Their Biosynthetic Genes, Functions, and Practical Use.

The nutritional and pharmaceutical values of long-chain polyunsaturated fatty acids (LC-PUFAs) such as arachidonic, eicosapentaenoic and docosahexaenoic acids have been well recognized. These LC-PUFAs are physiologically important compounds in bacteria and eukaryotes. Although little is known about the biosynthetic mechanisms and functions of LC-PUFAs in bacteria compared to those in higher organisms, a combination of genetic, bioinformatic, and molecular biological approaches to LC-PUFA-producing bacteria and some eukaryotes have revealed the notably diverse organization of the pfa genes encoding a polyunsaturated fatty acid synthase complex (PUFA synthase), the LC-PUFA biosynthetic processes, and tertiary structures of the domains of this enzyme. In bacteria, LC-PUFAs appear to take part in specific functions facilitating individual membrane proteins rather than in the adjustment of the physical fluidity of the whole cell membrane. Very long chain polyunsaturated hydrocarbons (LC-HCs) such as hentriacontanonaene are considered to be closely related to LC-PUFAs in their biosynthesis and function. The possible role of LC-HCs in strictly anaerobic bacteria under aerobic and anaerobic environments and the evolutionary relationships of anaerobic and aerobic bacteria carrying pfa-like genes are also discussed.

Occurrence of trans monounsaturated and polyunsaturated fatty acids in Colwellia psychrerythraea strain 34H.

Colwellia psychrerythraea strain 34H is an obligately psychrophilic bacterium that has been used as a model cold-adapted microorganism because of its psychrophilic growth profile, significant production of cold-active enzymes, and cryoprotectant extracellular polysaccharide substances. However, its fatty acid components, particularly trans unsaturated fatty acids and long-chain polyunsaturated fatty acids (LC-PUFAs), have not been fully investigated. In this study, we biochemically identified Δ9-trans hexadecenoic acid [16:1(9t)] and LC-PUFAs such as docosahexaenoic acid. These results are comparable with the fact that the strain 34H genome sequence includes pfa and cti genes that are responsible for the biosynthesis of LC-PUFAs and trans unsaturated fatty acids, respectively. Strain 34H cells grown under static conditions at 5 °C had higher levels of 16:1(9t) than those grown under shaken conditions, and this change was accompanied by an antiparallel decrease in the levels of Δ9-cis hexadecenoic acid [16:1(9c)], suggesting that the cis-to-trans isomerization reaction of 16:1(9c) is activated under static (microanaerobic) culture conditions, that is, the enzyme could be activated by the decreased dissolved oxygen concentration of cultures. On the other hand, the levels of LC-PUFAs were too low (less than 3% of the total), even for cells grown at 5 °C, to evaluate their cold-adaptive function in this bacterium.

Structural Confirmation of a Unique Carotenoid Lactoside, P457, in Symbiodinium sp. Strain nbrc 104787 Isolated from a Sea Anemone and its Distribution in Dinoflagellates and Various Marine Organisms.

The molecular structure of the carotenoid lactoside P457, (3S,5R,6R,3'S,5'R,6'S)-13'-cis-5,6-epoxy-3',5'-dihydroxy-3-(ß-d-galactosyl-(1→4)-ß-d-glucosyl)oxy-6',7'-didehydro-5,6,7,8,5',6'-hexahydro-ß,ß-caroten-20-al, was confirmed by spectroscopic methods using Symbiodinium sp. strain NBRC 104787 cells isolated from a sea anemone. Among various algae, cyanobacteria, land plants, and marine invertebrates, the distribution of this unique diglycosyl carotenoid was restricted to free-living peridinin-containing dinoflagellates and marine invertebrates that harbor peridinin-containing zooxanthellae. Neoxanthin appeared to be a common precursor for biosynthesis of peridinin and P457, although neoxanthin was not found in peridinin-containing dinoflagellates. Fucoxanthin-containing dinoflagellates did not possess peridinin or P457; green dinoflagellates, which contain chlorophyll a and b, did not contain peridinin, fucoxanthin, or P457; and no unicellular algae containing both peridinin and P457, other than peridinin-containing dinoflagellates, have been observed. Therefore, the biosynthetic pathways for peridinin and P457 may have been coestablished during the evolution of dinoflagellates after the host heterotrophic eukaryotic microorganism formed a symbiotic association with red alga that does not contain peridinin or P457.

The depth of tumor invasion beyond the outer border of the muscularis propria as a prognostic factor for T3 rectal/rectosigmoid cancer.

UNLABELLED: The distance of tumor invasion beyond the outer border of the muscularis propria (DBM) was measured whether it would be useful as a prognostic factor of the locally advanced rectal and rectosigmoid cancer was analyzed. PATIENTS AND METHODS: One hundred patients with rectal and rectosigmoid cancer invaded beyond muscularis propria who underwent surgery between 1996 and 2000 were included in this study. Patients who died due to other disease were excluded. Univariate and multivariate analyses of the risk factors including DBM for disease-free and cancer-related survival after surgery were performed. RESULTS: The median DBM was 4,000 microm and patients were thus classified into 2 groups by DBM (<4,000 microm and > or =4,000 microm). In univariate analysis, patients with a DBM of > or =4000 microm had a significantly poorer prognosis both for cancer-related survival (CRS) (p=0.004) and disease-free survival (DFS) (p=0.0025). Within many prognostic factors, lymphatic invasion (p=0.025), venous invasion (p=0.0402) and pattern of tumor infiltration (p=0.043) significantly correlated with DBM. In multivariate analysis with other factors including histology (p=0.0403), node status (p=0.0003), lymphatic invasion (p=0.0004), venous invasion (p<0.0001), tumor budding (p=0.0343) and pattern of tumor infiltration (p=0.0160), DBM was selected as the most significant prognostic factor for both CRS (hazard ratio (HR): 2.1682, 95% confidence interval (CI): 1.3606-3.8097, p=0.0019) and DFS (HR: 2.0654, 95% CI: 1.2696-3.8257, p=0.0075). CONCLUSION: Since DBM was the most significant prognostic factor, it could be used to categorize T-factor in clinical staging of advanced rectal and rectosigmoid cancer.

Polytene chromosomal maps of 11 Drosophila species: the order of genomic scaffolds inferred from genetic and physical maps.

The sequencing of the 12 genomes of members of the genus Drosophila was taken as an opportunity to reevaluate the genetic and physical maps for 11 of the species, in part to aid in the mapping of assembled scaffolds. Here, we present an overview of the importance of cytogenetic maps to Drosophila biology and to the concepts of chromosomal evolution. Physical and genetic markers were used to anchor the genome assembly scaffolds to the polytene chromosomal maps for each species. In addition, a computational approach was used to anchor smaller scaffolds on the basis of the analysis of syntenic blocks. We present the chromosomal map data from each of the 11 sequenced non-Drosophila melanogaster species as a series of sections. Each section reviews the history of the polytene chromosome maps for each species, presents the new polytene chromosome maps, and anchors the genomic scaffolds to the cytological maps using genetic and physical markers. The mapping data agree with Muller's idea that the majority of Drosophila genes are syntenic. Despite the conservation of genes within homologous chromosome arms across species, the karyotypes of these species have changed through the fusion of chromosomal arms followed by subsequent rearrangement events.

Triangulating anastomosis using a linear cutter in a colectomy.

BACKGROUND/AIMS: We have performed end-to-end anastomosis by the triangulating method using a linear cutter for the reconstruction in colectomy. In this report, we present our technique of triangle anastomosis and its convenience and merits. METHODOLOGY: Patients who underwent end-to-end anastomosis with the triangulating method, or the Gambee procedure, for reconstruction after colon cancer surgery from 1998 to 2003 in our department, were analyzed retrospectively. The anastomosis time and complications were compared in these two groups. RESULTS: The mean anastomosis time was 14.7+/-3.5 minutes, which is 17+/-0.7 shorter than the 31.7+/-4.2 minutes it took for the Gambee anastomosis performed during the same period. There were no significant differences in the incidences and variety of complications. CONCLUSIONS: Triangulating anastomosis using a linear cutter is a safe and easy technique that can be performed in a short amount of time. It is, therefore, considered a useful method for reconstructive surgery for colon cancer.

Indication and efficacy of adjuvant chemotherapy with oral fluoropyrimidines for dukes' B colorectal cancer.

BACKGROUND: Identifing patients prone to colorectal cancer recurrence is of importance in providing appropriate adjuvant chemotherapy. In this retrospective study on Dukes' B colorectal cancer, patients at high risk of recurrence were identified by clinicopathological factors, and the efficacy of adjuvant chemotherapy with oral fluoropyrimidines was evaluated. PATIENTS AND METHODS: The subjects were 229 patients with Dukes' B colorectal cancer who had undergone curative surgical resection. The relationship between each factor and cancer-related survival was examined. RESULTS: In all the patients, the 5-year cumulative survival rate was 83.5% and the recurrence rate was 20.1%. The multivariate analyses indicated that the depth of invasion was the most significant prognostic factor. The cases with tumor exposed at the serosa or which invaded other organs were considered as a high-risk group. The 5-year survival rate in high-risk patients with adjuvant chemotherapy was significantly better than those without chemotherapy (75.8% and 44.0%, respectively, p=0.0008). The patients who received chemotherapy tended to show a decrease in the recurrence rate, especially in the liver and lung (p=0.0346). CONCLUSION: In Dukes' B colorectal cancer, the cases with invasion depth se or si were considered to be at high risk of recurrence or death. Adjuvant chemotherapy was effective for such high-risk patients, especially decreasing recurrence in the liver and lung.

[Can the survival of patients with recurrent disease after curative resection of colorectal cancer be prolonged by the administration of cimetidine?].

Administration of cimetidine after curative surgery can improve prognosis of patients with colorectal cancer. In this study, we analyzed whether cimetidine can influence the survival of patients with a recurrent disease after colorectal surgery. The subjects were 29 patients with recurrent disease: 14 patients were administered with cimetidine and 15 patients were not. In the cimetidine administered group, seven cases were recurrent in the liver, 5 cases in a local site and 1 case in the lymph node, whereas 7 cases were recurrent in the liver, 4 cases in a local site and 3 cases in the lung for the non-cimetidine administered group. There were no significant differences for both groups in terms of patient's survival after recurrence. Although it was not significant, the patient's survival after curative resection of recurrent disease for the cimetidine administered group was better than the non cimetidine administered group. Although the results did not show cimetidine could influence the overall survival of the patients after recurrence, it might be possible to improve the survival of the patients after resection of the recurrent disease.

Low-dose leucovorin and 5-Fluorouracil for unresectable multiple liver metastasis from colorectal cancer.

UNLABELLED: In the present study, a retrospective investigation was conducted to determine whether or not it was possible to obtain a comparable survival time, response rate (RR) and modest toxicity combining low-dose leucovorin (LV) and 5-Fluorouracil (5-FU) (LV/5-FU) with hepatic arterial infusion (HAI) or systemic intravenous infusion (SI) for patients with unresectable liver metastasis from colorectal cancer (CRC). PATIENTS AND METHODS: Patients were given LV at 20 mg/m2 immediately followed by 5-FU at 370 mg/m2 with a 2-hour SI or HAI daily for 5 consecutive days with courses repeated every 5 weeks. Twenty patients received HAI and 16 patients received SI. Survival, response and toxicity were assessed. RESULTS: The median survival time (MST) of all patients was 20.0 months. The MST of the HAI and SI patients was 24.5 and 18.9 months, respectively. Two patients had complete remission (CR), 8 partial response (PR) and 14 no change (NC), which resulted in an RR of 28%. The MST according to the responses of CR/PR, NC and progressive disease (PD) patients was 45.5, 20.2 and 11.2 months, respectively. Severe toxicity (grades 3 or 4) to this regimen occured only in 0-10% of the cases, and there were no treatment-related deaths. CONCLUSION: There was no difference in response and survival between HAI and SI, which could be interpreted as a favorable result. Regardless of the route of administration, low-dose LV/5-FU treatment should be considered for patients with liver metastasis from CRC.

[Hepatic arterial infusion (HAI) chemotherapy achieved a complete response (CR) for multiple liver metastases of colorectal cancer--two case reports].

We encountered two cases of concurrent multiple liver metastases of colorectal cancer in two patients who achieved a complete response (CR) to hepatic arterial infusion (HAI) chemotherapy. The first case is a 64-year old man who was found to have anemia, and a diagnosis of ascending colon cancer was made. There were 6 metastatic lesions in both lobes of the liver. A right hemicolectomy was performed. Postoperative chemotherapy consisted of 2 g of oral UFT-E as well as 3 mg of CDDP and 500 mg of 5-FU administered by HAI. The metastatic lesions disappeared after 9 courses of chemotherapy were carried out. A partial hepatectomy was performed in the scarred area. Histopathological examination revealed no cancer cells. No recurrence has been observed for 4 years and 10 months since achieving CR. The second case is a 69-year-old man who had thin stool and bloody stool. Rectal cancer was diagnosed. Five metastatic lesions were noted in both lobes of the liver. A low anterior resection was performed. l-LV 25 mg and 5-FU 500 mg were given postoperatively by HAI. After three courses of chemotherapy postoperatively, metastatic lesions disappeared. No recurrence has been noted for 2 years and 1 month since achieving CR. HAI chemotherapy is considered one of the useful treatment options for patients with multiple liver metastases of colorectal cancer.

How many lymph nodes should be examined in Dukes' B colorectal cancer? Determination on the basis of cumulative survival rate.

BACKGROUND/AIMS: We analyzed how many lymph nodes should be examined to establish the presence or absence of lymph node metastasis, a staging factor, based on cumulative survival rate in colorectal cancer. METHODOLOGY: Among those who had undergone curative resection of colorectal cancer and lymphadenectomy exceeding D2, 94 patients with Dukes' B colorectal cancer (group B) and 108 patients with Dukes' C colorectal cancer (group C) were investigated, excluding obvious deaths from other diseases. Group B was divided into two groups by the number of lymph nodes examined, and the minimum number of retrieved lymph nodes yielding significant difference in survival rate was determined. RESULTS: Dividing group B into two groups by the number of lymph nodes examined, survival rate was studied. The minimum number of retrieved lymph nodes yielding significant difference in survival rate between the two groups was observed when group B was divided into one group with 9 or more lymph nodes (72 patients) and the other with less than 9 (22 patients), with cumulative five-year survival rate of 86.7% and 66.7%, respectively. More favorable prognoses were observed in the 9 or more group compared with the less than 9 group or Dukes' C group (p=0.0284, p=0.0032, respectively). On the other hand, survival rate of the less than 9 group was similar to that of the Dukes' C group (p=0.8167). CONCLUSIONS: Based on survival rate, 9 or more lymph nodes should be examined in order to correctly ascertain nodal negativity in lymphadenectomy exceeding D2 for Dukes' B colorectal cancer.

[Host immunity in colorectal cancer patients treated with low-dose Leucovorin plus 5-fluorouracil].

In colorectal cancer, low-dose Leucovorin plus 5-FU therapy does not induce any severe adverse effects, and patients could receive this therapy for many cycles. The aim of this study was to investigate the relationship between host immunity and this regimen. Seven patients were enrolled in this study. Host immunity was investigated before and after chemotherapy. The ratio of Th1/Th2, PHA response, serum IAP level and the productions of IL-6, IL-10 and soluble IL-2 receptor did not change significantly before and after chemotherapy. Since low-dose Leucovorin plus 5-FU therapy might not influence host immunity, patients could receive the therapy for a long duration without toxicity.

Prophylactic efficacy of allopurinol ice ball for leucovorin/5-fluorouracil therapy-induced stomatitis.

BACKGROUND: Stomatitis in cancer chemotherapy manifests with pronounced subjective symptoms, lowers the patient's quality of life (QOL) and may necessitate the discontinuation of chemotherapy. There have been few effective therapies established to date for chemotherapy-induced stomatitis. PATIENTS AND METHODS: We used frozen allopurinol solution (allopurinol ice balls) in the prevention of stomatitis associated with leucovorin (LV)/5-fluorouracil (5-FU) therapy for colon cancer. RESULTS: Among 32 patients undergoing LV/5-FU therapy, without the use of the allopurinol ice balls, 15 patients developed stomatitis. On the other hand, only 3 patients developed stomatitis among 20 patients receiving the chemotherapy in conjunction with allopurinol ice balls (p=0.0187). Seven patients who developed stomatitis during a course of chemotherapy without allopurinol ice balls were administered the ice balls in the subsequent course; 6 of these patients responded with lessened severity of stomatitis. In 2 of these responders, stomatitis of comparable severity recurred on discontinuation of the medication. CONCLUSION: Concomitant use of allopurinol ice balls is effective in preventing stomatitis in patients undergoing LV/5-FU therapy.

[Effect of cimetidine with chemotherapy on stage IV colorectal cancer].

We herein report the result of a prospective study to investigate the efficacy of cimetidine administration in conjunction with chemotherapy for stage IV colorectal cancer. Sixty-two patients treated with Leucovorin/5-fluorouracil therapy were enrolled from 1996 to 2000. Both groups were well matched for pre-treatment characteristics. There was no difference in survival in cur B patients. However, the cimetidine group had significantly prolonged survival in the patients with cur C or non-resectable carcinoma. This study suggests that cimetidine treatment may improve the survival of patients with non-curative surgery for stage IV colorectal cancer.

Second-line chemotherapy with low-dose CPT-11 and cisplatin for colorectal cancer resistant to 5-FU-based chemotherapy.

PURPOSE: With the aim of reducing the toxicities of irinotecan (CPT-11) while maintaining its antitumor effect, we treated colorectal cancer patients resistant to chemotherapy based on 5-fluorouracil (5-FU) with low-dose CPT-11 and cisplatin (CDDP). METHODS: CPT-11 (27 mg/m2) and CDDP (6 mg/m2) were administered on days 1, 8 and 15 every 4 weeks to 20 patients with recurrent or metastatic colorectal cancer. When toxicities were noted, administrations were delayed or the dose was reduced. RESULTS: No severe toxicity (i.e. grade 3 or more) was observed in this study. Nausea was observed in 50% of patients (10/20) and fatigue in 30% (6/20). Only four patients developed leukopenia (three grade 1 and one grade 2). Although the overall response rate was 15% (three partial response, seven no change, and ten progressive disease), the median time to progression was 7.0 months and the median survival time was 18.0 months. The treatment was well tolerated as outpatient therapy. CONCLUSION: Low-dose CPT-11 and CDDP treatment should be considered as second-line chemotherapy for patients with recurrent or metastatic colorectal cancer resistant to 5-FU-based chemotherapy.