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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.

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.

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 %).

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.

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.

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.

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.