Hydraulic adjustment of Scots pine across Europe

* The variability of branch-level hydraulic properties was assessed across 12 Scots pine populations covering a wide range of environmental conditions, including some of the southernmost populations of the species. The aims were to relate this variability to differences in climate, and to study the potential tradeoffs between traits. * Traits measured included wood density, radial growth, xylem anatomy, sapwood- and leaf-specific hydraulic conductivity (K(S) and K(L)), vulnerability to embolism, leaf-to-sapwood area ratio (A(L) : A(S)), needle carbon isotope discrimination (Delta13C) and nitrogen content, and specific leaf area. * Between-population variability was high for most of the hydraulic traits studied, but it was directly associated with climate dryness (defined as a combination of atmospheric moisture demand and availability) only for A(L) : A(S), K(L) and Delta13C. Shoot radial growth and A(L) : A(S) declined with stand development, which is consistent with a strategy to avoid exceedingly low water potentials as tree size increases. In addition, we did not find evidence at the intraspecific level of some associations between hydraulic traits that have been commonly reported across species. * The adjustment of Scots pine's hydraulic system to local climatic conditions occurred primarily through modifications of A(L) : A(S) and direct stomatal control, whereas intraspecific variation in vulnerability to embolism and leaf physiology appears to be limited.

Use of partial liver resection according to carcinologic procedures as an alternative to liver transplantation for HCC

e15628

Background: There are some arguments showing that anatomic resection, anterior approach and preoperative transarterial chemoembolization (TACE) with portal vein embolization (PVE) before major resection improves long term survival after partial liver resection for HCC. This oncologic approach could compete with liver transplantation (LT) which remains poorly accessible in western countries and inaccessible in the greatest part of the world.The aim of this study was to evaluate in patients with good liver function.the result of partial liver resection with an intended carcinologic approach. Methods: Between 1998 and 2007, among 210 patients resected for HCC, we selected a subgroup of 36 patients with single and small HCC (< 6 cm) developed on chronic liver disease (CLD) who underwent anatomic partial resection and anterior approach and TACE and PVE in case of major resection. Results: These 36 patients aged 37 to 76 years included 26 males (72%). Underlying CLD included hepatitis C in 16 (44%); hepatitis B in 8 (22%); alcohol in 9 (25%) and other in 3 ( 8%). The mean size of the tumor was 5.2 cm and 86% (n=31) had major resection. Operative mortality was 2.7% (n=1) and the overall 1-, 3- and 5-year survival rate were 92%,85%,73% while the disease free 1-, 3-, 5-year survival was 80%, 74%, 58%. Tumor recurrence occurred in 16 cases( 44%) after a mean delay of 21 months (ranging from 5 to 58 months). Recurrence was located out of the resected location in 6 cases. Conclusions: Partial liver resection for small tumors in patients with good liver function according to carcinologic procedures allow an excellent overall and disease free survival which can challenge LT. In the case of single HCC <6cm on chronic liver disease, this surgical approach may therefore be considered as a valuable alternative to LT within a curative intent.

No significant financial relationships to disclose.

Localization of the site of oxygen radical generation inside the complex I of heart and nonsynaptic brain mammalian mitochondria

Mitochondrial production of oxygen radicals seems to be involved in many diseases and aging. Recent studies clearly showed that a substantial part of the free radical generation of rodent mitochondria comes from complex I. It is thus important to further localize the free radical generator site within this respiratory complex. In this study, superoxide production by heart and nonsynaptic brain submitochondrial particles from up to seven mammalian species, showing different longevities, were studied under different conditions. The results, taking together, show that rotenone stimulates NADH-supported superoxide generation, confirming that complex I is a source of oxygen radicals in mammals, in general. The rotenone-stimulated NADH-supported superoxide production of the heart and nonsynaptic brain mammalian submitochondrial particles was inhibited both by p-chloromercuribenzoate and by ethoxyformic anhydride. These results localize the complex I oxygen radical generator between the ferricyanide and the ubiquinone reduction site, making iron-sulfur centers possible candidates, although unstable semiquinones can not be discarded. The results also indicate that the previously described inverse correlation between rates of mitochondrial oxygen radical generation and mammalian longevity operates through mechanisms dependent on the presence of intact functional mitochondria.

[Impact of the French consensus guidelines on the management of colonic and rectal cancer: a population-based study]

AIM

To compare the management of colorectal cancer (CRC) before and after the French consensus conferences of rectal cancer (RC) in 1994 and colonic cancer (CC) in 1998.

METHODS

From 344 CCR incident cases in 1992 and 545 in 2000, patient characteristics, tumor data, and diagnostic and treatment modalities were collected to compare the management of CRC.

RESULTS

Post-operative mortality did not change significantly (4% in 1992 and 2.8% in 2000). No trends were observed in disease stage at diagnosis or rate of resection. For patients with CC (n=244 in 1992 and n=396 in 2000), the number of resection specimens with at least 12 lymph nodes increased from 11% in 1992 to 27% in 2000 (p<0.001). For CC with Dukes stage C and D, the use of chemotherapy increased significantly: for Dukes Stage C from 45% in 1992 to 55% in 2000; for Dukes Stage D from 37% in 1992 to 67% in 2000. For patients with RC (n=100 in 1992 and n=149 in 2000), no change in use of adjuvant radiotherapy was observed: 59% in 1992 versus 53.4% in 2000. Preoperative radiotherapy for RC was performed in 63% in 1992 and 75% in 2000 (p=0.7).

CONCLUSION

The consensus guidelines appear to have moderately influenced management practices. A better diffusion of guidelines to practitioners and a systematic evaluation of actual practices would be helpful to improve their impact.

Genetic analysis of BRCA1 and BRCA2 in breast/ovarian cancer families from Aragon (Spain): two novel truncating mutations and a large genomic deletion in BRCA1

We screened BRCA1 and BRCA2 germline mutations in 60 high-risk breast and/or ovarian cancer patients and 20 relatives from Aragon (Spain) by DHPLC (Denaturing High Performance Liquid Chromatography) and direct sequencing of the entire coding sequence and the splicing sites of both genes. We have identified 17 different pathogenic mutations: 8 in BRCA1 and 9 in BRCA2 in 60 unrelated patients and 50% of relatives were carriers. The prevalence of pathogenic mutations in this study was 33.33%. Two truncating mutations are novel: c.5024_5025delGA in exon 16 of BRCA1 and c.2929delC in exon 11 of BRCA2 (numbered after GenBank U14680 and U43746). Multiplex Ligation Dependent Probe Amplification (MLPA) was performed for large mutational scanning of both genes and a large genomic deletion in BRCA1 was found (DelEx8-13). Furthermore, five mutations are described for the first time in Spanish population: c.1191delC, c.3478_3479delTT and c.6633_6637delCTTAA (BRCA1) and c.3972_3975delTGAG and 3908_3909delTG (BRCA2). Three mutations have been reported previously once in Spain: c.3600_3610del11 (BRCA1), c.5804_5807delTTAA (BRCA2) and c.9246C>A (BRCA2). The mutation c.5374_5377delTATG has been found before only in two unrelated families from Castilla-Leon, Spain (BRCA2). Frequent mutations described in Spanish population have also been present: c.187_188delAG, c.5242C>A and c.5385insC in BRCA1 and c.3492_3493insT and c.9254_9258delATCAT in BRCA2. c.5242C>A, 3972_3975delTGAG and c.5804_5807delTTAA were the recurrent mutations found. Fifteen different unclassified variants were identified (25% families). Although specific BRCA1 and BRCA2 mutations are recurrently reported as a result of genetic founder effects we conclude that heterogeneous ethnicity increases the variety of mutations that can be found in Spanish populations.

[Treatment of biliary injuries after laparoscopic cholecystectomy: retrospective study of 27 patients]

Biliary injuries after laparoscopic cholecystectomy are rare but serious. Their mortality rate can reach 9%.

AIM OF THE STUDY

Describe the management of biliary injuries after laparoscopic cholecystectomy in our center.

PATIENTS

Between January 1995 and June 2005, 27 patients (13 women, 14 men) were treated. The mean age was 53 years old (range, 18-92 years). The biliary injuries were common bile duct sections (n=16, 60%), common bile duct stenoses (n=5, 18.5%), biliary fistulas from the cystic duct (n=4, 15%), and biliary fistulas from an aberrant biliary duct (n=2, 7.5%).

RESULTS

Acute cholecystis was present in 40% of cases (n=11). An intraoperative cholangiography was done in 12 patients (44%). The mortality rate was 0%. Of the common bile duct sections, 43% were diagnosed during the cholecystectomy (n=7) or after the cholecystectomy within a mean of 11.2 days (n=9). Common bile duct injuries were treated in 16 cases with hepatojejunostomy and in five cases with an external biliary drain. Fistulas from the cystic duct were diagnosed within a mean 14.8 days. A fistula from an aberrant biliary duct was diagnosed during the cholecystectomy (n=1) or in the second postoperative day (n=1). Fistulas were treated with a clip on the cystic duct (n=2), an external biliary drain (n=1), a biliary endoprosthesis (n=1), and the biliary aberrant duct suture (n=2).

CONCLUSION

Common bile duct injuries are a serious complication because their treatment is a hepaticojejunostomy in 75% of cases.

The histone deacetylase inhibitor trichostatin A induces GADD45 gamma expression via Oct and NF-Y binding sites

The GADD45gamma protein is a potential tumor suppressor whose expression is reduced in several tumors. However, very little is known about the regulation of its expression. We have determined that the most relevant region of its promoter lies between nucleotides -112 and -54, relative to the transcription start site. Putative Oct and NF-Y elements were found in this region and factors belonging to these families interacted with these elements in vitro and with the promoter in vivo. Mutation of these elements reduced the basal activity of the promoter, suggesting that both sites are essential for basal expression. These factors interact with chromatin modifying proteins and we found that histone deacetylase 1 or silencing mediator for retinoid and thyroid hormone receptor overexpression reduced the basal activity of the promoter. In contrast, forced expression of the histone acetylase protein PCAF or cell treatment with the HDAC inhibitor trichostatin A increased GADD45gamma mRNA levels and induced GADD45gamma promoter activity through its Oct and NF-Y elements. Moreover, ectopic expression of a dominant-negative version of NF-YA strongly inhibited trichostatin A-induced activation of the promoter. Our data strongly suggest that inhibition of deacetylase activity could potentially be used for treatment of tumors where GADD45gamma expression is reduced.

Phase II study of a fixed dose-rate infusion of gemcitabine associated with erlotinib in advanced pancreatic carcinoma

15013

Background: The efficacy of gemcitabine in pancreatic cancer can be improved by its combination with erlotinib. Likewise, a fixed dose-rate infusion of gemcitabine seems to be superior to the conventional 30-minute infusion. Our objective was to evaluate the efficacy and toxicity of a fixed dose-rate infusion of gemcitabine associated with erlotinib in patients with advanced adenocarcinoma of the pancreas. Methods: From May 2005 to October 2006, 21 chemotherapy-naïve patients were included, median age 62 years (range 47 - 78), male/female 12/9. Five patients (24%) had locally advanced disease and 16 (76%) distant metastases. The Karnofsky score was 80–100 in 11 (52%), and 60–70 in 10 (48%). Treatment consisted of gemcitabine 1200 mg/m2 given as a 120-minute infusion on days 1, 8, 15, plus erlotinib 100 mg p.o daily. Cycles were repeated every 4 weeks. Results: A total of 80 cycles of chemotherapy were delivered with a median of 3.8 per patient (range 1- 8). There were five partial responses (24%, 95% CI: 8.4 - 47.6%), whereas seven patients had stable disease (33%) and 9 had a progression (43%). The median time to progression was 4 months. After a median follow-up of 6 months (1–14 months), the median overall survival has not been achieved. Toxicity was low. Grade 3- 4 WHO toxicities per patient were as follows: neutropenia in 5 (24%), thrombocytopenia in 1 (5%) and anaemia in 3 (14%). Grade 1–2 rash appeared in 8 (38%) and grade 3 in 3 (14%). Four patients (19%) had diarrhoea grade 1–2. Conclusions: These preliminary results suggest that a fixed dose-rate infusion of gemcitabine associated with erlotinib is active and well tolerated in patients with advanced pancreatic carcinoma.

No significant financial relationships to disclose.

Molecular epidemiology of emergent multidrug-resistant Salmonella enterica serotype Typhimurium strains carrying the virulence resistance plasmid pUO-StVR2

OBJECTIVES

To evaluate the incidence of a distinct multidrug-resistant (MDR) grouping of Salmonella serotype Typhimurium strains carrying the hybrid virulence resistance plasmid pUO-StVR2, and its possible evolution in the region where it was first detected [Principality of Asturias (PA), Spain].

METHODS

pUO-StVR2-containing isolates were tentatively identified by two genetic markers: the bla(OXA-30) gene and the class 1 integron InH:2000 bp/bla(OXA-30)-aadA1a. Positive isolates were examined for resistance profile (RP), plasmid content, virulence profile (VP) and genomic polymorphisms using macrorestriction-PFGE.

RESULTS

A total of 182 out of 248 Typhimurium clinical isolates recorded in the PA over 2001-02 were ampicillin-resistant and could be distributed into several MDR groupings. A MDR grouping carrying pUO-StVR2, with a defined RP (AMP/bla(OXA-30), CHL/catA1, [STR-SPT]/[strA/B,aadA1a], SUL/[sul1,sul2], TET/tet(B), qacEDelta1, merA, +/-TMP/dfrA12, and containing InH), was represented by 49 isolates. The VPs of these isolates (24 genes screened) differed from that of the type strain LT2 by the absence of the sopE1 and pef genes. Macrorestriction analysis established six combined XbaI/BlnI PFGE profiles, and supported a clonal relationship among most of the isolates.

CONCLUSIONS

During 2001-02, the isolates carrying pUO-StVR2 constituted the second most frequent S. Typhimurium MDR grouping recorded in the PA, preceded only by the pandemic pentaresistant DT104. Polymorphisms on the genomic DNA, different phage types, different plasmid profiles and the detection of trimethoprim resistance in one isolate encoded by an additional plasmid, were consistent with both intra-cluster evolution and horizontal transfer of the hybrid plasmid.

Modulation of peroxisome proliferator-activated receptors (PPARs) by PPARα- and PPARγ-specific ligands and by 17β-estradiol in isolated zebrafish hepatocytes

Peroxisome proliferation is a phenomenon occurring when responsive animals are exposed to certain compounds so-called peroxisome proliferators and is regulated through a nuclear receptor named peroxisome proliferator-activated receptor (PPAR). PPAR family members exhibit a strong binding affinity for both saturated and unsaturated fatty acids. Activators of PPAR(alpha) include a variety of endogenously present fatty acids, leukotrienes and hydroxyeicosatetraenoic acids (HETEs) and clinically used drugs, such as fibrates. PPAR(beta) activators include fatty acids, prostaglandin A2 (PGA2) and prostacyclin (PGI2). PPAR(gamma) is the most selective receptor and, among others, 15-deoxy-Delta(12,14) prostaglandin J2 (PGJ2) has been described to be a PPAR(gamma)-specific ligand. The aim of the present study was to determine if known PPAR(alpha) and PPAR(gamma) ligands were able to alter the expression of these subtypes in an in vitro model of zebrafish primary hepatocyte culture. With this purpose, a PPAR(alpha) specific ligand (8S-HETE), a PPARgamma specific ligand (PGJ) and a peroxisome proliferator of the fibrate class (clofibrate) were selected. In addition, the female hormone 17beta-estradiol was also used as it is known to interact with PPARs. After cell exposure for 24 h, cells were immunohistochemically stained for both PPARs and immunolabeling was quantified as percentage of positive nuclei and cells. Levels of expression of PPARs were also measured by image analysis as grey level per cell. Expression was induced for both PPAR(alpha) and PPAR(gamma) by clofibrate (at 0.5 mM for PPAR(alpha) and at 1 and 2 mM for PPAR(gamma)), by HETE (1 microM), and by PGJ2 (0.3 and 1 microM for PPAR(alpha) and 0.3 microM for PPAR(gamma)). Expression of PPARgamma was also induced at 10 microM by 17beta-estradiol. The percentage of PPAR(alpha) positive nuclei increased significantly at 1 microM HETE and the percentage of PPAR(gamma) positive cells decreased at 10 microM 17beta-estradiol. As a conclusion, clofibrate, HETE and PGJ2 are able to induce expression of both PPAR(alpha) and PPAR(gamma) in zebrafish primary hepatocyte cultures. Further studies are needed to identify how the expression of different PPAR subtypes is regulated and to elucidate the implication of PPAR subtypes in zebrafish cell functions.

Randomized phase II trial of carboplatin versus paclitaxel and carboplatin in platinum-sensitive recurrent advanced ovarian carcinoma: a GEICO (Grupo Espanol de Investigacion en Cancer de Ovario) study

BACKGROUND

The aim of this study was to determine whether the response rate for the paclitaxel-carboplatin combination is superior to carboplatin alone in the treatment of patients with platinum-sensitive recurrent ovarian carcinoma.

PATIENTS AND METHODS

Patients with recurrent ovarian carcinoma, 6 months after treatment with a platinum-based regimen and with no more than two previous chemotherapy lines, were randomized to receive carboplatin area under the curve (AUC) 5 (arm A) or paclitaxel 175 mg/m(2) + carboplatin AUC 5 (arm B). The primary end point was objective response, following a 'pick up the winner' design. Secondary end points included time to progression (TTP), overall survival, tolerability and quality of life (QoL).

RESULTS

Eighty-one patients were randomized and included in the intention-to-treat analysis. The response rate in arm B was 75.6% [26.8% complete response (CR) + 48.8% partial response (PR)] [95% confidence interval (CI) 59.7% to 87.6%] and 50% in arm A (20% CR + 30% PR) (95% CI 33.8% to 66.2%). No significant differences were observed in grade 3-4 hematological toxicity. Conversely, mucositis, myalgia/arthralgia and peripheral neurophaty were more frequent in arm B. Median TTP was 49.1 weeks in arm B (95% CI 36.9-61.3) and 33.7 weeks in arm A (95% CI 25.8-41.5). No significant differences were found in the QoL analysis.

CONCLUSIONS

Paclitaxel-carboplatin combination is a tolerable regimen with a higher response rate than carboplatin monotherapy in platinum-sensitive recurrent ovarian carcinoma.

Nitrogen assimilation and nitrogen control in cyanobacteria

Nitrogen sources commonly used by cyanobacteria include ammonium, nitrate, nitrite, urea and atmospheric N2, and some cyanobacteria can also assimilate arginine or glutamine. ABC (ATP-binding cassette)-type permeases are involved in the uptake of nitrate/nitrite, urea and most amino acids, whereas secondary transporters take up ammonium and, in some strains, nitrate/nitrite. In cyanobacteria, nitrate and nitrite reductases are ferredoxin-dependent enzymes, arginine is catabolized by a combination of the urea cycle and arginase pathway, and urea is degraded by a Ni2+-dependent urease. These pathways provide ammonium that is incorporated into carbon skeletons through the glutamine synthetase–glutamate synthase cycle, in which 2-oxoglutarate is the final nitrogen acceptor. The expression of many nitrogen assimilation genes is subjected to regulation being activated by the nitrogen-control transcription factor NtcA, which is autoregulatory and whose activity appears to be influenced by 2-oxoglutarate and the signal transduction protein PII. In some filamentous cyanobacteria, N2 fixation takes place in specialized cells called heterocysts that differentiate from vegetative cells in a process strictly controlled by NtcA.