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The elemental composition of the deep particle flux at 500 m, 1500 m and 3200 m was measured at the Oceanic Flux Program (OFP) time-series site in the northern Sargasso Sea from September 2000 to March 2015. The results clearly show that the deep particle flux is sourced from two components: an “extrinsic flux” component that is derived from and temporally coupled with recent surface export fluxes, and an “intrinsic flux” component that is derived from chemical scavenging and suspended particle aggregation within the deep water column. Elemental fluxes show a seasonal cycle that is closely tied to the overlying cycle in primary production. Fluxes of biogenic minerals and nutrient elements peak during the late winter-spring maximum in overlying primary production. A small late winter-spring peak in fluxes of non-biogenic elements suggests that intrinsic flux generation within the deep water column also covaries with overlying production and the extrinsic flux. Flux elemental composition also shows a marked seasonal cycle that reflects dilution of the intrinsic flux in the late winter and spring with fresh biogenic materials sourced from recent overlying production. Factor of four increases in lithogenic element fluxes and lithogenic element ratios indicate that the source of the deep lithogenic flux is not Saharan dust but North American margin sediments that have been resuspended and advected to the region via Gulf Stream recirculation. High rates of authigenic mineral precipitation accompany organic matter degradation in mesopelagic waters. The excess Mn flux (i.e. flux not supported by lithogenic minerals) increases by an order of magnitude between 500 m and 1500 m, and the excess Ba flux increases by a factor of three. There is a major reorganization of element associations with flux carrier phases with increasing depth. In particular, the geochemical behavior and flux of P becomes increasingly independent of organic carrier phases and the geochemical behavior of Fe, Co, Ni, Cu and, to a lesser extent, V and Pb becomes increasingly controlled by manganese oxide scavenging. This article is part of a special issue entitled: “Cycles of trace elements and isotopes in the ocean – GEOTRACES and beyond” - edited by Tim M. Conway, Tristan Horner, Yves Plancherel, and Aridane G. Gonzalez.

The prescription of proton pump inhibitors (PPIs) seems excessive. Taken over the long term, PPIs can cause serious side effects. It therefore turns out to be justified to suspend treatments whose expected benefit seems too low compared to the risks involved : it is deprescription. The objective of this study is to assess a process for the deprescription of PPIs in a hospital internal medicine department.After collegial deliberation, an algorithm for assisting in the deprescription of PPIs was validated. If necessary, the PPI was phased out over 1 month. A telephone follow-up at 1, 2 and 3 months was carried out in order to assess the maintenance of deprescription and the occurrence of digestive symptoms. The evaluation criteria were the rate of deprescription and the rate of maintenance of deprescription at 3 months following reports from patients, their caregivers or a family member.105 patients with a mean age of 72 years were included over a period of 21 weeks, and in 31 cases (29%), deprescription was performed. After 3 months of follow-up, there was 71% maintenance of deprescription. Three patients were lost to follow-up and 6 patients resumed PPI.The approach undertaken resulted in the suspension of PPI intake in almost 3 out of 10 cases. This result was maintained at least three months for a large majority of patients. It will be interesting to continue this process and extend the monitoring over longer periods, in order to ensure that PPI de-prescription is maintained in the long term.

This study compares lipid biomarker and bulk constituents (organic carbon and δ13C, nitrogen and carbonate) in particles (30–4400 m depth) collected at the Oceanic Flux Program site in the northern Sargasso Sea off Bermuda during three periods of contrasting oceanographic conditions: following the spring bloom (April 2015), during the low productivity period (November 2015), and two weeks after the passage of the Category 3 Hurricane Nicole (October 2016). Lipids biomarkers were used to evaluate the contributions of phytoplankton, zooplankton and bacterial sources to the particulate organic carbon (POC), diagenetic transformations of suspended POC throughout the water column and within the nepheloid layer, and seasonal and non-seasonal temporal variability, including the impact of an extreme weather event. Depth profiles of lipid concentration and molecular composition showed seasonal and non-seasonal variability in particle composition throughout the water column. Higher lipid concentrations in April versus November 2015 reflected differences in plankton productivity, while relative abundances in diagnostic phytosterols, C18 polyunsaturated fatty acids and alkenones reflected differences in phytoplankton community structure. A rapid decrease in lipid biomarker concentrations below the euphotic zone was accompanied by a marked transition in lipid composition, e.g. increases in the relative percentages of cholesterol, C16-C18 fatty alcohols, odd- and branched- chain fatty acids. This reveals the intense remineralization of algal-derived carbon and fresh inputs of organic materials from zooplankton and microbial production within the upper mesopelagic zone. Particulate lipids within the bathypelagic zone reveal a close connectivity of deep particulate carbon composition with upper ocean properties, while compositional heterogeneity with depth reflects continuous particle turnover and de novo particle production throughout the deep water column. Additionally, depth trends in the within-class composition of fatty alcohols and bacterial fatty acids were observed, suggesting depth zonation of zooplankton and microbial community structure. Hurricane Nicole (October 2016) strongly impacted upper ocean physics and nutrient supply, resulting in a transient phytoplankton bloom/flux event that increased concentrations of fresh particulate phytodetritus (e.g., C18 polyunsaturated fatty acids) throughout the mesopelagic and upper bathypelagic zones. Concurrent increases in zooplankton and bacterial lipid biomarkers (e.g., 18:1ω9, odd- and branched-chain fatty acids, cholesterol) indicated that this transient pulse of labile carbon stimulated mesopelagic zooplankton and microbial activity, resulting in an enrichment of labile materials in the suspended particle pool throughout the deep ocean. Our study demonstrates that extreme weather events can have a major impact on carbon flux and particle cycling in the deep ocean, with pronounced implications for the ocean carbon pump and deep ocean ecosystems.

Patients admitted from emergency units represent a large portion of the population in internal medicine departments. The aim of this study is to identify characteristics of patients and organization of these departments.Between June 29th and July 26th 2015, voluntary internal medicine departments from the SiFMI group prospectively filled anonymized internet forms to collect data of each patients admitted in their ward from emergency units, during seven consecutive days.Three hundred and sixty-five patients from emergency departments were admitted in 18 internal medicine inpatients departments, totalling 1100 beds and 33,530 annual stays, 56% of them for emergency units inpatients. Mean age was 68 years, 54% were women, mean Charlson score was 2.6 and 44% of the patients took at least three drugs. Main causes of hospitalization were infectious (29%) and neurological (17%) diseases. Mean length of stay was 9.2 days. The medical team was composed by a median value of 4,5 [2,75-6,25] senior full-time equivalents, 86% were internists. Each department except one received residents, two third of them were from general medicine.This study highlights a high organizational variability among internal medicine departments and patients, and sets internal medicine as a specialty with a great capacity to achieve an integrative/comprehensive management of patients and to offer a comprehensive basis for physicians in training.

Resume Nous rapportons le cas d’un homme de 43 ans ayant fait une hemorragie meningee. Une granulomatose a eosinophiles avec polyangeite (GEPA) a ete diagnostiquee devant l’association : asthme, polypose naso-sinusienne, neuropathie des sciatiques poplites externes, signes generaux, eosinophilie a 4000/mm3, CRP a 50 mg/L et presence de pANCA avec anti-MPO a 74 U/mL. L’arteriographie etait normale. Il a ete traite par methylprednisolone et cyclophosphamide, permettant une remission prolongee sans sequelle. Seulement 17 cas d’hemorragie du systeme nerveux central au cours de la GEPA ont ete rapportes. La GEPA peut etre revelee par cette complication comme dans 7 des cas rapportes (41 %).

L’encephalopathie de Gayet-Wernicke (EGW) est une atteinte du systeme nerveux central liee a une carence en thiamine (vitamine B1) largement decrite chez les patients alcooliques denutris, chez qui la prevention systematique est bien ancree dans les pratiques. Ce diagnostic merite cependant d’etre evoque en dehors de toute addiction a l’alcool, des etudes anatomopathologiques montrant que l’EGW est sous-diagnostiquee. Nous rapportons les cas de trois patients. Pour chacun, l’EGW est survenue lors de la prise en charge et les symptomes ont partiellement regresse sous vitaminotherapie. La vitamine B1 etait constamment abaissee, mais l’IRM cerebrale evocatrice seulement dans un cas. L’interet des presentations reside dans le terrain des patients: aucun n’etait ethylique chronique et deux etaient en surpoids. Il est important de connaitre les autres situations a risque de carence (denutrition recente, consommateurs de sucres raffines, resection digestive, vomissements chroniques, grossesse, nutrition parenterale sans supplements vitaminiques), de maniere a prevenir l’EGW, surtout si le patient est traite par du serum glucose. Il faut savoir que le tableau clinique peut se resumer a une confusion isolee ou une apathie, devant conduire a un traitement par thiamine parenterale au moindre doute, sans attendre les examens complementaires, d’autant qu’il est bien tolere. L’urgentiste peut jouer un role cle dans la prevention de cette pathologie en debutant une vitaminotherapie dans toute situation a risque.

The Oceanic Flux Program (OFP) sediment trap time series, the longest running time series of its kind, has continuously measured particle fluxes in the deep Sargasso Sea since 1978. OFP results provided the first direct observation of seasonality in the deep ocean, and they have documented the tight coupling between deep fluxes and upper ocean processes and the intensity of biological reprocessing of sinking flux in the ocean interior. The synergy among OFP and other research programs co-located at the Bermuda time-series site has provided unprecedented opportunities to study the linkages among ocean physics, biology, and chemistry; particle flux generation; and particle recycling in the ocean interior. The OFP time series is beginning to reveal how basin-scale climatic forcing, such as the North Atlantic Oscillation, affects the deep particle flux.

Fecal pellet flux and size distribution at 500, 1500 and 3200 m depths were measured in sediment trap samples collected by the Oceanic Flux Program time-series off Bermuda, December 2006–November 2007. During the study, three mesoscale eddies passed through: a cyclonic eddy in bloom stage (February through midApril), a decaying post-bloom mode-water eddy (late April through May), and an anticyclonic eddy (August through October). Variability associated with eddy passage masked any seasonal trends in flux or size distributions. At a depth of 1500 m, the fecal pellet flux ranged from a minimum of 100 pellets m day to a maximum of 500 pellets m day during the cyclonic eddy passage, corresponding to ranges in the fecal pellet mass and the carbon flux of 0.5– 1.7 mg m day and 0.07–0.25 mg C m day, respectively. Fecal pellets averaged 7+ 3% of the organic carbon flux, a minimum estimate as disassociated pellets were not quantifiable. Size distribution shifts indicated small zooplankton and immature stages were more abundant within the cyclonic eddy, whereas larger zooplankton were present within the mode water and anticyclonic eddies. The fecal pellet number, flux and size distributions showed no consistent depth trends and indicated extensive fecal pellet reprocessing within the water column.

Symbiotic fungi’s role in providing nitrogen to host plants is well-studied in tundra at Toolik Lake, Alaska, but little-studied in the adjoining boreal forest ecosystem. Along a 570 km north–south transect from the Yukon River to the North Slope of Alaska, the 15N content was strongly reduced in ectomycorrhizal and ericoid mycorrhizal plants including Betula , Salix , Picea mariana (P. Mill.) B.S.P., Picea glauca Moench (Voss), and ericaceous plants. Compared with the 15N content of soil, the foliage of nonmycorrhizal plants ( Carex and Eriophorum ) was unchanged, whereas content of the ectomycorrhizal fungi was very much higher (e.g., Boletaceae, Leccinum and Cortinarius ). It is hypothesized that similar processes operate in tundra and boreal forest, both nitrogen-limited ecosystems: (i) mycorrhizal fungi break down soil polymers and take up amino acids or other nitrogen compounds; (ii) mycorrhizal fungi fractionate against 15N during production of transfer compounds; (iii) host plants are accordingly depleted in 15N; and (iv) mycorrhizal fungi are enriched in 15N. Increased N availability for plant roots or decreased light availability to understory plants may have decreased N allocation to mycorrhizal partners and increased δ15N by 3‰–4‰ for southern populations of Vaccinium vitis-idaea L. and Salix. Fungal biomass, measured as ergosterol, correlated strongly with soil organic matter and attained amounts similar to those in temperate forest soils.

Breastfeeding is often contraindicated when drugs are prescribed for a chronic maternal disease. Many of the restrictions are based on theoretical concerns only and may be excessively cautious. An updated review is mandatory. Many antirheumatic drugs can be safely used during lactation: nonsteroidal anti-inflammatory drugs, corticosteroids, sulfasalazine, antimalarial agents. Doubt remains about safety of cochicine or dapsone. Expert opinions still diverge but move on in favor the use of azathioprine, ciclosporin, and even methotrexate. Leflunomide, mycophenolate mofetil and cyclophosphamide are contraindicated. No conclusion can be reached regarding anti-TNF-alpha and rituximab. Current knowledge about drug transfer in breast-milk and cumulative empirical data have expanded the possibilities to allow breastfeeding when the mother is treated with antirheumatic medications. The data provided by pharmaceutical industry should not be the only source of the physician's information in the risk assessment.

Background Radiofrequency-assisted laparoscopic liver resection is reported. Methods Patients suitable for liver resection were carefully assessed for laparoscopic resection. Patient and intraoperative and postoperative data were prospectively collected and analyzed. Results Eighteen patients underwent laparoscopic liver resection. All operations were performed without vascular clamping and consisting of tumorectomy (n = 9), multiple tumoretcomies (n = 2), segmentectomy (n = 2), and bisegmentectomies (n = 2). Mean blood loss was 121 ± 68 mL, and mean resection was time 167 ± 45 minutes. There was no need for perioperative or postoperative transfusion of blood or blood products. One patient developed pneumothorax during surgery as a result of direct puncture of pleura with the radiofrequency probe, and 1 patient had transient liver failure and required supportive care after surgery. The mean length of hospital stay was 6.0 ±1.5 days. At follow-up, those with liver cancer had no recurrence. Conclusions Radiofrequency-assist laparoscopic liver resection can decrease the risk of intraoperative bleeding and blood transfusion.

The growing incidence of burn-out syndrome among physicians has become a major concern for public policy. The root causes are not fully understood. We make the assumption that the most powerful cause of their suffering at work is the challenging of physician's practical judgment. Practical judgment is the faculty, which connects knowledge and reason, science and experience, general and individual issues. It lies at the core of medical action and its exercise is closely associated with a pleasure at work. The evolution of medicine, particularly the proliferation of procedures, has a harmful influence on its training and its exercise.

Calycophyllum spruceanum (Benth.) Hook. f. ex K. Shum. is an important timber-tree species in the Peruvian Amazon Basin. As farmers and industry often use wood from young trees, it is important to investigate variation in juvenile wood properties in this species. A provenance/progeny test was established to evaluate genetic variation in growth and wood properties of young trees, the strength of their genetic control as well as their interrelationships both at the genetic and the phenotypic level in different planting zones. In this paper, results are presented for tree height and stem diameter (near ground level) at 16, 28 and 39 months; and stem diameter and basic density of the wood at breast height at 39 months. Significant variation due to provenances and especially due to families within provenances was found in growth and wood density. Phenotypic and genetic correlations indicated that larger trees tended to have denser wood. Wood density had higher heritability than height and diameter; and genetic control over height, diameter and density was generally highest in the planting zone where trees grew most rapidly.

Bulk aerosols (>1 μm) were collected continuously above the canopy at the Howland Experimental Forest, Maine, USA from May to October 2002. Each sample integrated over an approximately 2-week period. Mono- and disaccharide sugars were extracted using a microscale technique and were analyzed as their TMS derivatives by gas chromatography–mass spectrometry (GC–MS). Concentrations of total aerosol sugars ranged from 10 to 180 ng m −3 . Glucose was the most abundant sugar (40–75% of the total sugars). The monosaccharides arabinose, fructose, galactose, mannose, arabitol and mannitol, and the disaccharides sucrose, maltose and mycose (aka trehalose) were also present in lower concentrations. The sugar composition in the aerosols varied seasonally. Fructose and sucrose were prevalent in early spring and decreased in relative abundance as the growing season progressed. Sugar polyols (arabitol and mannitol) and the disaccharide mycose (a fungal metabolite) were more prevalent in autumn during the period of leaf senescence. The changes in the sugar composition in the aerosol samples appear to reflect the seasonality of sugar production and utilization by the ecosystem. Plant waxes were present as significant components also indicating an input from biogenic background. Smoke plumes from Quebec forest fires passed over the Howland site in early July 2002. Levoglucosan, a biomarker of biomass burning, increased by an order of magnitude in the aerosol samples collected during this time. Glucose, mannose, arabinose, galactose, and also, plant waxes increased in concentration by factors of 2–5 in the smoke-impacted samples, indicating that wildfires enhance atmospheric emissions of uncombusted organic compounds. In contrast, concentrations of fructose, sugar polyols and disaccharides were not significantly higher in the smoke-impacted samples and indicated that biomass burning was not a significant source of these compounds in the aerosols.

Considerable attention has recently been focused on the role of eddies in affecting biogeochemical fluxes and budgets of the Sargasso Sea. In late November 1996, the Bermuda Testbed Mooring (BTM) and Bermuda Atlantic Time Series (BATS) shipboard sampling evidenced a fall phytoplankton bloom at the Bermuda time-series site which was strongly forced by the interplay between seasonal mixed layer destratification and perturbation of mixed layer dynamics due to passage of a warm mesoscale feature. The feature was characterized by clockwise current vector rotation from near the surface to about 200 m and a thick, warm, low salinity isothermal layer >180 m in depth. Nutrients, chlorophyll fluorescence and pigment profiles indicated high primary production stimulated by enhancement of nutrient entrainment and intermittent deep mixing down to the base of the feature's isothermal layer. Nearly coincident with the arrival of this productive feature at the BTM site, the Oceanic Flux Program (OFP) sediment traps recorded an abrupt, factor of 2.5 increase in mass flux at 3200 m depth. Even more dramatic was the observed increase in flux of labile bioreactive organic matter. Fluxes of primary phytoplankton-derived compounds increased by factors of 7–30, bacteria-derived compounds by 6–9, and early degradation products of sterols by a factor of 10. The covariation of early degradation products and bacteria-derived compounds with phytoplankton-derived compounds indicated that the settling phytoplankton bloom material contained elevated bacterial populations and was undergoing active degradation when it entered the 3200 m trap cup. The increase in the flux of bulk components, especially the residual silicate fraction, and refractory organic compounds clearly preceded the main pulse of the labile, surface-derived phytoplankton organic material. The coincident increase in the flux of refractory and zooplankton-derived compounds suggests that in the initial stage of the deep flux event, the mass flux increased largely as a result of an increase in the flux of refractory materials scavenged from the water column and repackaged into sinking particles and increased zooplankton inputs. These results imply that biological reprocessing of flux material within the water column acts to enhance the coupling between the surface and deep ocean environments. Our results show that transient, upper ocean forcing associated with variable upper ocean physical structure—which includes but is not limited to eddies—and variable meteorological forcing can have an enormous effect on the export flux of bioreactive organic material. The importance of pulsed fluxes of bioreactive material arising from transient physical forcing to the long-term average is not presently known. However, the occurrence of episodic high flux events throughout the OFP time-series record (also inferred from BTM time-series) suggests that such forcing, regardless of specific dynamics, may be responsible for a significant fraction of the total export flux of bioreactive carbon and associated elements to the deep oligotrophic ocean.

Background The surgical strategy for treatment of synchronous colorectal liver metastases remains controversial. The outcome and overall survival of patients presenting with such metastases, treated either by simultaneous resection or by delayed resection, were evaluated. Methods From 1987 to 2000, 97 patients presented with synchronous colorectal liver metastases, of whom 35 (36 per cent) underwent a simultaneous resection and 62 patients (64 per cent) a delayed resection. Simultaneous resection was considered prospectively for patients with fewer than four unilobar metastases. Results Age, blood transfusion requirements, operating time, duration of inflow occlusion, hospital stay and mortality rate were similar in the two groups. The morbidity rate did not differ significantly (23 per cent after simultaneous resection and 32 per cent after delayed resection). The location of the primary tumour and extent of liver resection did not influence the morbidity rate significantly in the simultaneous resection group. The overall survival rate was 94, 45 and 21 per cent at 1, 3 and 5 years respectively after simultaneous resection, and 92, 45 and 22 per cent after delayed resection. Conclusion In selected patients, simultaneous resection of the colorectal primary tumour and liver metastases does not increase mortality or morbidity rates compared with delayed resection, even if a left colectomy and/or a major hepatectomy are required.

We measured the molecular and carbon isotopic composition of major leaf wax compound classes in northern mixed mesic prairie species (Agropyron smithii, Stipa viridula, Bouteloua gracilis, Tragopogon dubius) and in selected crops (Triticum aestivum, Brassica napus, Hordeum vulgare, Medicago sativa) of southern Alberta and also in aerosols collected 4 m above the prairie canopy. Our aims were to better constrain the wax biosynthetic carbon isotopic fractionation relative to the plant's carbon isotopic discrimination and to quantitatively assess the correspondence between wax composition in vegetation and in boundary layer aerosols. Wax molecular composition of the C3 prairie species and bulked vegetation was characterized by high abundance of C28 n-alkanol and C31 n-alkane compounds whereas the C4 species B. gracilis had several co-dominant n-alkanol and n-alkane compounds. Wax molecular composition of crop species differed significantly from that of prairie vegetation and was often dominated by a single compound. Results indicate that leaf wax isotopic composition is quantitatively related to the plant's carbon isotopic discrimination. Although species variations were evident, n-alcohol, n-acid and n-alkane wax compounds were on average depleted in 13C by approximately 6.0±1‰ relative to total plant carbon. The magnitude of the depletion in wax δ13C was unaffected by environmental factors which altered photosynthetic carbon isotopic discrimination. No consistent difference in the magnitude of wax biosynthetic fractionation was observed between C3 and C4 species, indicating that photosynthetic pathway has little influence on the isotopic fractionation of wax during biosynthesis. The isotopic composition of ablated waxes in aerosols collected above the canopy was similar to that of the grassland vegetation but the molecular composition differed significantly and indicated that the source "footprint" of the ablated leaf wax particles we sampled in boundary layer air masses was of a regional or larger spatial scale.

Resumen El tratamiento quirurgico de las metastasis hepaticas constituye la unica opcion terapeutica de tipo curativo. La reseccion quirurgica presenta indices de supervivencia claramente superiores a los obtenidos con otros tratamientos, en particular con la quimioterapia. Sin embargo, solo del 10 al 20% de los pacientes pueden tratarse mediante reseccion hepatica. Durante la ultima decada, se han propuesto estrategias innovadoras que combinan la utilizacion de nuevas tecnicas para incrementar el numero de pacientes que pueden acceder a un tratamiento quirurgico, como la destruccion tumoral con radiofrecuencia o crioterapia, la embolizacion portal y la quimioterapia neoadyuvante. En este capitulo, se exponen las tecnicas de reseccion hepatica y las nuevas estrategias utilizadas para convertir en resecables metastasis hepaticas que inicialmente no lo eran. Se consideraran unicamente las metastasis hepaticas del cancer colorrectal, que constituyen la indicacion mas frecuente de reseccion. Del resto de metastasis hepaticas que pueden beneficiarse con un tratamiento quirurgico, pueden citarse las metastasis hepaticas del cancer de mama, el melanoma, los tumores endocrinos y, en menor proporcion, el cancer de rinon.

Bevacizumab is an antibody directed against VEGF-A. It is approved for the treatment of many cancer diseases. Its side effects are currently not well known by physicians.A 70-year-old female with metastatic colonic adenocarcinoma was admitted in the intensive care unit because of a coma, four days after having received a combined monthly chemotherapy containing bevacizumab, oxaliplatine, 5 fluorouracil, and folinic acid for the fourth time. On clinical examination, she presented with lower limbs spasticity and hypertension. Etiologic investigations, including cerebral tomodensitometry, cerebrospinal fluid examination, psychotropic drugs urinary testing, and electroencephalogram, were negative. Consciousness improved without any other treatment than nicardipine and urapidil, but the patient was initially confused. Cerebral magnetic resonance imaging showed changes suggestive of posterior reversible encephalopathy syndrome, but also involving frontal lobes. There were additional biological and echocardiographic changes suggestive of cardiac involvement. The patient recovered completely of both cardiac and neurologic manifestations 10 days later.Physicians should be aware of cardiovascular adverse effects of bevacizumab. High blood pressure must be treated to avoid more severe complications. When a posterior reversible encephalopathy syndrome occurs, cardiac involvement should be investigated.

Haptophyte algae-derived long-chain C 37 -C 39 alkenones and alkyl alkenoates were analyzed in euphotic zone particulate matter collected over a 7 yr period at the Oceanic Flux Program/Bermuda Atlantic Time Series (OFP/BATS) site in the western Sargasso Sea. Surface water temperatures at the site range annually from 19 to 29°C. Alkenone concentrations ranged from −1 in summer to > 100 ng L −1 following the passage of storms. Highest seasonal concentrations occurred during the late winter and spring. Under stratified conditions, alkenone concentrations in the surface mixed layer (0–20 m) were generally 2 to 4 times higher than in the deep fluorescent maximum (75–110 m), consistent with Emiliania huxleyi concentration profiles (Haidar and Thierstein, 2001) and indicated that alkenone production primarily occurs within the upper euphotic zone in this region. Alkenone compound distributions and the temperature calibrations of C 37 and C 38 methyl and ethyl alkenone unsaturation (U 37 K′ , U 38Me K , and U 38Et K , respectively) were remarkably similar to that observed in an E. huxleyi strain previously isolated from the same area (Conte et al., 1998) , providing strong evidence that E. huxleyi is the predominant alkenone synthesizer and that characteristics exhibited by randomly isolated clones in culture are, in many cases, consistent with those of populations in the region of origin. The Bermuda calibration of U 37 K′ vs. water temperature (U 37 K′ = −1.9835 + 0.2004T − 0.0034T 2 , r 2 = 0.95, n = 91) is nonlinear and falls along the same trendline as euphotic zone particulates from warm (> 15°C) waters of the eastern North Atlantic (Conte and Eglinton, 1993) and Mediterranean (Ternois et al., 1997) . The combined North Atlantic temperature calibration (U 37 K′ = − 1.1365 + 0.1257T − 0.0018T 2 , r 2 = 0.963, n = 134) differs significantly from published coretop sediment calibrations (Rosell-Mele et al., 1995; Muller et al., 1998) based on sea surface temperature maps (Levitus and Boyer, 1994) , having a steeper slope at temperatures 24°C. The reasons are not clearly apparent and manifest a need for detailed studies linking production patterns in surface waters with the signal arriving at the seafloor to fully understand the generation of the sedimentary signal.

Resumen El cancer de pancreas exocrino sigue siendo de mal pronostico pese a los progresos de las resecciones que han permitido reducir la mortalidad operatoria, que era del 25 % en los anos sesenta, a menos del 3 % en la actualidad. En el momento del diagnostico, solo podra considerarse una reseccion con fines curativos en el 20 % de los casos. El tratamiento paliativo no mejora la supervivencia de los pacientes sino su bienestar al permitir la desaparicion de las complicaciones mecanicas y/o algicas a cambio de una morbilidad minima. El tratamiento paliativo puede realizarse mediante tecnicas quirurgicas o no quirurgicas. Las tecnicas no quirurgicas estan reservadas, en principio, a los pacientes en mal estado general y con una estenosis biliar aislada. Para los otros pacientes y con mayor motivo en caso de estenosis biliar y digestiva, podra proponerse el tratamiento quirurgico, ya sea de primera intencion si el examen preoperatorio pone de manifiesto un tumor inextirpable o de necesidad si durante una laparotomia por tumor pancreatico se encuentra en la exploracion una contraindicacion para la exeresis curativa. El tratamiento quirurgico paliativo de la ictericia se realizara la mayoria de las veces mediante una anastomosis biliodigestiva. Se asociara una gastroenteroanastomosis de base. Una esplacnicectomia peroperatoria mediante neurolisis quimica de preferencia permite obtener buenos resultados en lo concerniente al dolor. La funcion de la laparoscopia podria sobrepasar el examen de extension ya que las ventajas relacionadas con el postoperatorio, en potencia mas sencillo, de la cirugia laparoscopica representan un triunfo en pacientes a menudo fragiles cuya esperanza de vida es limitada.

Resume But de l'etude Les metastases hepatiques synchrones et resecables des cancers colorectaux doivent-elles etre traitees dans le meme temps que la tumeur primitive ou secondairement ? L'analyse retrospective de notre serie a pour but de preciser les circonstances, les indications et les resultats de la procedure en un temps. Materiel et methodes Du 1er janvier 1982 au 31 decembre 1996, 146 patients ont ete operes par resection hepatique pour metastase d'un cancer colorectal. Cinquanteneuf patients (40 %) etaient porteurs de metastases hepatiques synchrones. Chez 28 patients (47,5 %) a ete realisee une resection simultanee de la tumeur primitive et des metastases hepatiques (groupe des resections simultanees: RS). Chez les 31 autres patients (52,5 %), la resection hepatique a ete differee avec un delai moyen de 6 ± 4 mois (groupe des resections differees: RD). Resultats L'âge moyen des deux groupes n'etait pas significativement different (56 ans versus 60 ans). Le recours a la transfusion sanguine et la quantite de sang transfusee n'etaient pas significativement differents entre les deux groupes. La duree operatoire etait comparable (320 ± 76 min [RS] versus 308 ± 88 min [RD]). Des complications ont ete observees dans 18 % des cas pour le groupe RS et 16 % des cas pour le groupe RD (NS). La mortalite operatoire a ete nulle dans les deux groupes. La survie a ete de 86, 63, et 43 % a un, deux, et trois ans pour le groupe RS et 81, 51, et 36 % pour le groupe RD, sans difference significative entre les deux groupes. Conclusion Ces resultats confirment que la resection simultanee de la tumeur primitive et des metastases hepatiques n'augmente ni la morbidite ni la mortalite dans notre experience. Le meilleur candidat a la resection simultanee est represente par un patient porteur d'un cancer colique droit non complique, en bon etat general et ayant des metastases hepatiques synchrones resecables par une hepatectomie mineure.

Since 1978, the Oceanic Flux Program (OFP) time-series sediment trap study has continuously measured particle fluxes in the deep Sargasso Sea (31°50′N, 64°10′W). One feature of this 19+ year record has been the episodic occurrence of large, short-lived flux maxima that are not associated with the annual spring bloom. These maxima generally occur during the Dec.–Jan. period, but not necessarily every year. They have also occurred in other seasons. In January 1996, OFP traps located at 3200 and 3400 m depths intercepted a major flux “event” in which there was an abrupt, threefold increase in mass flux at both depths. Mass flux measured at 3200 m during the event (87 mg m -2 d -1 ) was the highest recorded since biweekly resolved sampling was begun in 1989. Organic biomarker analyses of material collected prior to, and during, this high flux event determined that there was an abrupt change in material composition associated with the sudden flux increase. Prior to the event, cholesterol, a single bacteriaderived C 27 hopanone (22,29,30-tris nor hopan-21-one), and saturated and odd/branched fatty acids predominated: these compounds indicated that the sedimenting material was extensively degraded. During the event, organic material was greatly enriched in C 26 –C 29 phytosterols, haptophyte algae-derived C 37 –C 39 alkenones, labile polyunsaturated acids, degradation products such as steroidal ketones, and also in bacteria-derived compounds such as C 27 –C 34 hopanoids and β and ω −1 hydroxy acids. These compounds indicated the organic fraction contained a large amount of relatively fresh phytoplankton-derived debris and tracers of bacterial biomass and metabolism, which suggested that the sinking material was undergoing active bacterial decomposition. Thus, the flux “event” appears to have resulted from a shortlived bloom in the overlying surface waters which, for reasons not currently apparent, was inefficiently remineralized in the upper ocean and rapidly settled to depth. These findings are the first direct documentation of episodic delivery of labile phytoplankton-derived detritus to the deep ocean in an oligotrophic mid-gyre region. Such transient productivity/flux events may account for a significant fraction of the export flux of biologically available carbon and easily remineralized elements, not only in highly productive areas, but throughout the deep oceans.

During the summer of 1995, we investigated the response of mud crab megalopae (Panopeus herbstii Milne-Edwards) to cues associated with adult habitat. Natural rock/shell substratum and the rock-associated seaweed, Fucus vesiculosus L., both induced metamorphosis of competent megalopae; natural sand substratum did not induce metamorphosis. Structural mimics of preferred substrata induced metamorphosis only when covered with natural biofilm. Clean mimics did not induce metamorphosis. Water-soluble exudates from preferred substrata showed weak induction of metamorphosis. Exudates from adult P. herbstii elicited a similar weak response. Exudates from another species of crab and from two fish predators did not induce metamorphosis. We conclude that water-soluble cues associated with major components of preferred adult habitat induce the metamorphic molt of P. herbstii megalopae. The three-dimensional structure of the substratum is not important in induction of metamorphosis, but the biofilm associated with preferred substratum plays a critical role. It is not clear whether the biofilm produces the water-soluble cue or simply provides a tactile stimulus that works in conjunction with the soluble cue.

This study describes experiments on sediment-estuarine water slurries originating from a Spartina alterniflora salt marsh. We investigated the fate of tin(IV) or monomethyltin cation (MeSn 3+ ) chlorides after their additon to slurries under anaerobic and aerobic conditions. We did not observe methylation of tin in anaerobic or aerobic slurries with and without added tin(IV). MeSn 3+ -amended samples occasionally formed small amounts of Me 2 Sn 2+ or Me 3 Sn + after extended periods of time, particularly when MeSn 3+ remained in solution. The stability of MeSn 3+ in slurries demonstrates that the absence of net methylation of tin(IV) is not due to rapid demethylation of MeSn 3+ or its further methylation. Inorganic tin concentrations in the aqueous phase of anaerobic slurries spiked with MeSn 3+ and unspiked slurries decreased by about 85% in 21 days and remained relatively constant until the end of the 59-day experiments. In similar anaerobic experiments about 25% of the MeSn 3+ spike was adsorbed to sediment within 1 h and about 75% was adsorbed within 10 days. The lack of methylation and demethylation reactions in our aerobic and anaerobic slurries, which contrasts with two previous reports, undoubtedly reflects the absence of added nutrients and low concentrations of added tin(IV) in our experiments. We believe that our model experiments more accurately reflect conditions in salt marshes than do previous studies. We conclude that future model studies on methylation of inorganic tin should include S. alterniflora because it is so prominent in observations of methyltin compounds in the estuary.

Symbiotic fungi's role in providing nitrogen to host plants is well-studied in tundra at Toolik Lake, Alaska, but little-studied in the adjoining boreal forest ecosystem. Along a 570 km north-south transect from the Yukon River to the North Slope of Alaska, the 15N content was strongly reduced in ectomycorrhizal and ericoid mycorrhizal plants including Betula, Salix, Picea mariana (P. Mill.) B.S.P., Picea glauca Moench (Voss), and ericaceous plants. Compared with the 15N content of soil, the foliage of nonmycorrhizal plants (Carex and Eriophorum) was unchanged, whereas content of the ectomycorrhizal fungi was very much higher (e.g., Boletaceae, Leccinum and Cortinarius). It is hypothesized that similar processes operate in tundra and boreal forest, both nitrogen-limited ecosystems: (i) mycorrhizal fungi break down soil polymers and take up amino acids or other nitrogen compounds; (ii) mycorrhizal fungi fractionate against 15N during production of transfer compounds; (iii) host plants are accordingly depleted in 15N; and (iv) mycorrhizal fungi are enriched in 15N. Increased N availability for plant roots or decreased light availability to understory plants may have decreased N allocation to mycorrhizal partners and increased delta15N by 3-4 parts per million for southern populations of Vaccinium vitis-idaea L. and Salix. Fungal biomass, measured as ergosterol, correlated strongly with soil organic matter and attained amounts similar to those in temperate forest soils.

The aim of our study was to evaluate the diagnostic contribution of (18)F-fluoro-deoxyglucose ((18)F-FDG)-positron emission tomography (PET)/computed tomography (CT) in patients with fever of unknown origin (FUO) or unexplained prolonged inflammatory syndrome (UPIS) in real life.We performed a retrospective study including 14 patients with FUO or UPIS hospitalised in our institution (Strasbourg University Hospital, France) between January 2005 and July 2006. (18)F-FDG-PET/CT was considered helpful when abnormal results allowed an accurate diagnosis.(18)F-FDG-PET/CT was helpful in half the patients (7/14) for final diagnosis. A diagnosis was reached in 87.5% of the patients (7/8) with an abnormal (18)F-FDG-PET/CT but only in 50% of the patients (3/6) with a normal (18)F-FDG-PET/CT. Conventional chest and abdominal CT was performed in 13 patients before ordering (18)F-FDG-PET/CT. We considered that (18)F-FDG-PET/CT was essential to establish the final diagnosis in only 23% of the patients (3/13) since neither chest nor abdominal CT identified abnormalities consistent with the final diagnosis. However, among the three patients, two were diagnosed with large vessel vasculitis and one patient with local prosthetic infection.Our study supports the potential interest of (18)F-FDG-PET/CT in the diagnostic workup of FUO and UPIS as it helped establish a fine diagnosis in half of the cases. However, (18)F-FDG-PET/CT appeared to be essential to the final diagnosis in only 23% of the cases. In our opinion, this protocol should be performed as a second level test, especially when conventional CT is normal or is unable to discriminate between active and silent lesions.

Breastfeeding is often contraindicated when drugs are prescribed for a chronic maternal disease. Many of the restrictions are based on theoretical concerns only and may be excessively cautious. An updated review is mandatory. Many antirheumatic drugs can be safely used during lactation: nonsteroidal anti-inflammatory drugs, corticosteroids, sulfasalazine, antimalarial agents. Doubt remains about safety of cochicine or dapsone. Expert opinions still diverge but move on in favor the use of azathioprine, ciclosporin, and even methotrexate. Leflunomide, mycophenolate mofetil and cyclophosphamide are contraindicated. No conclusion can be reached regarding anti-TNF-alpha and rituximab. Current knowledge about drug transfer in breast-milk and cumulative empirical data have expanded the possibilities to allow breastfeeding when the mother is treated with antirheumatic medications. The data provided by pharmaceutical industry should not be the only source of the physician's information in the risk assessment.

This paper highlights our experience of the transfer of hydrodynamic gene therapy (HGT) from the large animal, the pig, into clinical practice. The modification of balloon catheters and the development of a minimally invasive technique to allow selective isolation of liver segments for HGT in the large animal and human are described. Finally, our preliminary results from a phase I clinical study of HGT for thrombopoietin (TPO) in cirrhotic patients with thrombocytopenia are discussed. Based on these provisional data, minimally invasive selective HGT of liver segments appears to be technically safe, but further work is required to optimize the efficiency of gene transfer in order to achieve clinical benefit.

In this paper, we compile the current surface seawater C37 alkenone unsaturation (UK′37) measurements (n = 629, −1 to 30°C temperature range) to derive a global, field-based calibration of UK′37 with alkenone production temperature. A single nonlinear “global” surface water calibration of UK′37 accurately predicts alkenone production temperatures over the diversity of modern-day oceanic environments and alkenone-synthesizing populations (T = −0.957 + 54.293(UK′37) − 52.894(UK′37)2 + 28.321(UK′37)3, r2 = 0.97, n = 567). The mean standard error of estimation is 1.2°C with insignificant bias in estimated production temperature among the different ocean regions sampled. An exception to these trends is regions characterized by strong lateral advection and extreme productivity and temperature gradients (e.g., the Brazil-Malvinas Confluence). In contrast to the surface water data, the calibration of UK′37 in surface sediments with overlying annual mean sea surface temperature (AnnO) is best fit by a linear model (AnnO = 29.876(UK′37) − 1.334, r2 = 0.97, n = 592). The standard error of estimation (1.1°C) is similar to that of the surface water production calibration, but a higher degree of bias is observed among the regional data sets. The sediment calibration differs significantly from the surface water calibration. UK′37 in surface sediments is consistently higher than that predicted from AnnO and the surface water production temperature calibration, and the magnitude of the offset increases as the surface water AnnO decreases. We apply the global production temperature calibration to the coretop UK′37 data to estimate the coretop alkenone integrated production temperature (coretop IPT) and compare this with the overlying annual mean sea surface temperature (AnnO). We use simple models to explore the possible causes of the deviation observed between the coretop temperature signal, as estimated by UK′37, and AnnO. Our results indicate that the deviation can best be explained if seasonality in production and/or thermocline production as well as differential degradation of 37:3 and 37:2 alkenones both affect the sedimentary alkenone signal.

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Laparoscopic liver resection has not yet gained wide acceptance among hepatic surgeons, mainly because of the difficulties encountered in dealing with possible intraoperative bleeding. A new technique of laparoscopic liver resection is presented. A 43-year-old man with a large and symptomatic hemangioma underwent a laparoscopic radiofrequency energy-assisted liver resection. After induction of pneumoperitoneum, four trocars were introduced and intraoperative ultrasonography and coagulative desiccation were performed along a plane of tissue 1 cm away from the edge of the lesion using the Cool-Tip radiofrequency probe and a 500-kHz, radiofrequency generator. The necrosed band of parenchyma then was divided and the specimen removed. The operative time was 300 min with a resection time of 240 min. The intraoperative blood loss was 75 ml. The postoperative course was uneventful and the patient was discharged on postoperative day 6. Laparoscopic radiofrequency-assisted liver resection is feasible, and with greater experience may contribute to the wider use of mini-invasive video-assisted liver surgery.

Agroforestry ecosystems may be an important resource for conservation and sustainable use of tropical trees, but little is known of the genetic diversity they contain. Inga edulis, a widespread indigenous fruit tree in South America, is used as a model to assess the maintenance of genetic diversity in five planted vs. five natural stands in the Peruvian Amazon. Analysis of five SSR (simple sequence repeat) loci indicated lower allelic variation in planted stands [mean corrected allelic richness 31.3 (planted) and 39.3 (natural), P = 0.009]. Concerns regarding genetic erosion in planted Amazonian tree stands appear valid, although allelic variation on-farm is still relatively high.

Surgical resection is the only therapeutic option with curative effect on malignant liver tumours, but in over 70% of cases, this is not a feasible option. A prospective study was performed to assess the short- and long-term effects of intraoperative radiofrequency ablation on unresectable liver metastases. Between 1997 and 2001, 57 patients (mean age 61.9 years; range 31–83 years) with 297 unresectable liver metastases (colorectal adenocarcinoma, n=38; carcinoid tumour, n=4; malignant melanoma, n=3; other metastases, n=12) underwent intraoperative radiofrequency ablation. No mortality was observed in patients managed solely with radiofrequency ablation. Eight postoperative complications occurred in eight patients (14%). Three occurred when radiofrequency ablation was combined with resection. Of the 33 patients completely ablated, 30 patients are still alive and 21 are disease-free after a median follow-up of 18.1 months (range 2–43). Ten patients underwent more than one intraoperative radiofrequency ablation episode. Overall survival was 72.5% at 1 year and 52.5% at 3 years. Complete ablation and the number of lesions were significant independent prognostic factors for survival, with p

The problem of the extraction, representation, and utilization of meaning from English text has been elusive. Semantic parsing permits effective and relevant response to complex questions where the domain is well defined. The semantic net used is a three-row numeric matrix. Each column of the net represents an assertion about the domain. The meanings of each word are contained in associations (pointers to the names of things within the domain). The intersection of these pointers is used to define each phrase. Ambiguity is further reduced, when necessary, by an implementation of common sense-limiting the interpretations to those meanings that may be associated as the subject or object of each verb. Multiply embedded clauses are processed by passing the result of one clause as an argument for the next. By this means, complex expressions can be reduced to a single token. >

Carbon uptake by the oceans and by the terrestrial biosphere can be partitioned using changes in the (12)C/(13)C isotopic ratio (delta(13)C) of atmospheric carbon dioxide, because terrestrial photosynthesis strongly discriminates against (13)CO(2), whereas ocean uptake does not. This approach depends on accurate estimates of the carbon isotopic discrimination of terrestrial photosynthesis (Delta; ref. 5) at large regional scales, yet terrestrial ecosystem heterogeneity makes such estimates problematic. Here we show that ablated plant wax compounds in continental air masses can be used to estimate Delta over large spatial scales and at less than monthly temporal resolution. We measured plant waxes in continental air masses advected to Bermuda, which are mainly of North American origin, and used the wax isotopic composition to estimate Delta simply. Our estimates indicate a large (5 6 per thousand) seasonal variation in Delta of the temperate North American biosphere, with maximum discrimination occurring in late spring, coincident with the onset of production. We suggest that the observed seasonality arises from several factors, including seasonal shifts in the proportions of production by C(3) and C(4) plants, and environmentally controlled adjustments in the photosynthetic discrimination of C(3)-plant-dominated ecosystems.

Persistant hypocalcemia occurring after surgical treatment of severe primary hyperparathyroidism may be due to transient or permanent hypoparathyroidism but also to a bone disease. We report three cases of hypocalcemia after surgery of large parathyroid adenoma or hyperplasia in women. Plasma calcium, phosphate and PTH levels are in accordance with Hungry Bone Syndrome (HBS). HBS is related to both excessive bone demineralization and turn over. It is a major importance to distinguish HBS from surgical hypoparathyroidism in order to start early the appropriate treatment given for a long period.

To analyze the context in which acute colonic pseudo-obstructions occur in a medical practice.Retrospective study of patients with an acute colonic pseudo-obstruction hospitalized in an internal medicine department between November 1992 and December 1999.We found 12 patients including eight men (mean age: 80.2 years). All had abdominal pains. Seven patients presented an occlusive syndrome. A septic shock occurred in two subjects. The average diameter of the cecum was 10 cm. Distention involved the whole colon for nine patients, and only the left part for three. Six subjects were affected by a bronchopneumonia, three had a previous history of recent diarrhea, two had colonic diverticulitis, and two others had a diabetic neuropathy. Ogilvie's syndrome revealed hypothyroidism for one patient. Nine patients were taking one or more medications incriminated in the acute colonic pseudo-obstruction: calcium-channel blockers (n = 6), neuroleptics (n = 5), antidepressant agents (n = 4), dopaminergic drugs (n = 2) and opiates (n = 1). Five patients underwent a colonoscopic decompression. Surgical procedures were undertaken for three patients: one underwent a complete colectomy because of numerous perforation. Except for the colectomized patient, the outcome resulted in either recovery (n = 7), partial improvement (n = 3), or recurrence (n = 1).In a medical environment, acute colonic pseudo-obstruction is a pathology for elderly persons, namely with a masculine predominance and often associated with iatrogenic factors. The outcome is more often than not favorable, but it may result in invasive acts or significant complications at this age.

Retinal vein occlusion has several causes. Cardiovascular risk factors, particularly systemic hypertension; as well as thrombophilia appear to be involved in the development of retinal vein occlusion.In a retrospective study we analyzed these factors in 24 patients, admitted for retinal vein occlusion and isovolaemic hemodilution in an internal medicine unit.In patients over 50 years of age, cardiovascular risk factors predominate; while in patients under 50, one patient out of two has biological features indicating a risk for thrombosis.Serological abnormalities could be involved in the physiopathology of retinal vein occlusion in young patients.

The surgical strategy for the treatment of resectable synchronous hepatic metastases of colorectal cancer remains controversial. The retrospective analysis of our series of resectable synchronous hepatic metastases is focused on the percentage of simultaneous resections, the circumstances, the indications, and the results of the one-step procedure compared to the two-step strategy.From January 1st 1982 to December 31st 1996, 146 patients were operated on for resection of hepatic metastases of colorectal cancer. Fifty-nine (40%) presented with synchronous metastases, 28 (47.5%) of whom underwent simultaneous resection of the primary tumor and of the hepatic metastases (simultaneous resection group: SR). For the other 31 patients (52.5%), the hepatic resection was delayed for a mean interval of 6 +/- 4 months (delayed resection group: DR).The mean age in the two groups was not significantly different (56 years vs. 60 years). The need for blood transfusion and the volume required were not significantly different between the two groups. The duration of each surgical operation was comparable between the two groups (320 +/- 76 min vs. 308 +/- 88 min). Postoperative complications were observed in 18% of patients in the SR group and in 16% of patients in the DR group (no significant difference). There was no postoperative mortality in either group. Survival was 86, 63 and 43% at 1, 2, 3 years respectively in the SR group, and 81, 51 and 36% in the DR group, with no significant difference between the groups.Simultaneous resection of the primary tumor and the hepatic metastases does not increase neither mortality nor morbidity in our series. The best candidate for a one-step procedure is a patient with a right colonic tumor, in a good status, with liver synchronous metastases resectable by mean of a minor hepatectomy.