Continuous Sampling of Hydrothermal Fluids From Loihi Seamount After the 1996 Event

For at least 9 years prior to July 1996, hydrothermal fluids flowed from Pele\u27s Vents on Loihi Seamount, Hawaii. In July–August 1996 a tectonic-volcanic event occurred that destroyed Pele\u27s Vents, creating a pit crater (Pele\u27s Pit) and several sites with hydrothermal venting. In October 1996 we deployed two new continuous water samplers (OsmoSamplers) at two of these hydrothermal sites and collected fluids using traditional sampling techniques to monitor the evolution of crustal and hydrothermal conditions after the event. The samplers were recovered in September 1997, and additional discrete vent fluid samples were collected. The OsmoSampler located along the south rift at Naha Vents captured a change in composition from a low-chlorinity, high-K fluid (relative to bottom seawater) to a high-chlorinity, low-K fluid. These changes are consistent with the fluid cooling during ascent and being derived from several different sources, which include high- (\u3e330°C) and low- (330°C) into which magmatic volatiles were added. During the deployment, thermal and fluid fluxes decreased. At Naha the transport of heat and chemicals was decoupled. The chemical and thermal evolution of hydrothermal fluids after the event on Loihi is consistent with previous models based on events that have occurred along mid-ocean ridges. The event at Loihi clearly had an effect on the local hydrography; however, the integrated effect of chemical fluxes to global budgets from similar events is uncertain. Chemical fluxes from similar events may have a global impact, if ratios of chemical (e.g., CO2, Fe/Mn, Mg, sulfate, and K) to thermal anomalies greatly exceed, or are in the opposite direction to, fluxes from mid-ocean ridge hydrothermal systems

In situ enrichment of ocean crust microbes on igneous minerals and glasses using an osmotic flow-through device

Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 12 (2011): Q06007, doi:10.1029/2010GC003424.The Integrated Ocean Drilling Program (IODP) Hole 1301A on the eastern flank of Juan de Fuca Ridge was used in the first long-term deployment of microbial enrichment flow cells using osmotically driven pumps in a subseafloor borehole. Three novel osmotically driven colonization systems with unidirectional flow were deployed in the borehole and incubated for 4 years to determine the microbial colonization preferences for 12 minerals and glasses present in igneous rocks. Following recovery of the colonization systems, we measured cell density on the minerals and glasses by fluorescent staining and direct counting and found some significant differences between mineral samples. We also determined the abundance of mesophilic and thermophilic culturable organotrophs grown on marine R2A medium and identified isolates by partial 16S or 18S rDNA sequencing. We found that nine distinct phylotypes of culturable mesophilic oligotrophs were present on the minerals and glasses and that eight of the nine can reduce nitrate and oxidize iron. Fe(II)-rich olivine minerals had the highest density of total countable cells and culturable organotrophic mesophiles, as well as the only culturable organotrophic thermophiles. These results suggest that olivine (a common igneous mineral) in seawater-recharged ocean crust is capable of supporting microbial communities, that iron oxidation and nitrate reduction may be important physiological characteristics of ocean crust microbes, and that heterogeneously distributed minerals in marine igneous rocks likely influence the distribution of microbial communities in the ocean crust.The subseafloor flow cell enrichment chambers were funded by a small grant from the Ocean Drilling Program. This work was also funded by NASA grant NNX08AO22G, NSF OCE 0727119 to C.G.W., NSF OCE 0452333 to S.M.S., and OCE‐0550713 and OCE‐0727952 to A.T.F., PSU, and OSU

Video-supported Analysis of Beggiatoa Filament Growth, Breakage, and Movement

A marine Beggiatoa sp. was cultured in semi-solid agar with opposing oxygen-sulfide gradients. Growth pattern, breakage of filaments for multiplication, and movement directions of Beggiatoa filaments in the transparent agar were investigated by time-lapse video recording. The initial doubling time of cells was 15.7 ± 1.3 h (mean ± SD) at room temperature. Filaments grew up to an average length of 1.7 ± 0.2 mm, but filaments of up to approximately 6 mm were also present. First breakages of filaments occurred approximately 19 h after inoculation, and time-lapse movies illustrated that a parent filament could break into several daughter filaments within a few hours. In >20% of the cases, filament breakage occurred at the tip of a former loop. As filament breakage is accomplished by the presence of sacrificial cells, loop formation and the presence of sacrificial cells must coincide. We hypothesize that sacrificial cells enhance the chance of loop formation by interrupting the communication between two parts of one filament. With communication interrupted, these two parts of one filament can randomly move toward each other forming the tip of a loop at the sacrificial cell

Surgical Quality in Rectal Cancer Management: What Can Be Achieved by a Voluntary Observational Study?

Purpose. Countries with nationwide quality programmes in colorectal cancer report an improved outcome. In Germany, a self-organized and self-financed observational quality assurance project exists, based on voluntary participation. The object of the present study was to ascertain whether this nationwide project also improves the outcome of colorectal cancer. Methods. The German Quality Assurance in Colorectal Cancer Project started in 2000 and by 2012 contained 85,000 patients. Inclusion criteria for the study were participation for the entire period of 13 years and treatment of rectal cancer. The following parameters were analysed: (1) patient related: age, gender, ASA classification, T-stage, and N-stage, (2) system related: frequency of preoperative CT and MRI, and (3) outcome related: CRM status, complications, and hospital mortality. Results. Forty-one of the 345 hospitals treating 11,597 patients fulfilled the inclusion criteria. The median age increased from 67 to 69 years (p=0.002). ASA stages III and IV increased from 32.0% to 37.6% (p=0.005) and from 2.0% to 3.3% (p=0.022), respectively. The use of CT rose from 67.2% to 88.8% (p<0.001) and that of MRI from 5.0% to 35.2% (p<0.001). The proportion of patients suffering from complications decreased from 7.9% to 5.3% (p<0.001) for intraoperative and from 28.0% to 18.6% (p<0.001) for postoperative surgical complications, but general postoperative complications increased from 25.8% to 29.5% (p=0.006). The distribution of histopathological stage, anastomotic leakage, and in-hospital mortality did not change significantly. Conclusion. Participation in a quality assurance project improves compliance with treatment standards, especially for diagnostic procedures. An improvement of surgical results will require further investment in training

Comparison of Outcome Between Older and Younger Patients Following Surgery for Primary Hyperparathyroidism

The aim of the study was to compare preoperative findings, serum levels of calcium and parathormone (PTH) and outcome of patients undergoing surgery for primary hyperparathyroidism (pHPT) aged over 70 years with younger patients. Material and methods. Between January 1, 1996 and September 30, 2011 186 patients underwent surgery for pHPT. Patient data were collected from chart reviews and an electronically stored database. Groups were defined as patients aged 70 years or older and patients younger than 70 years. Outcome comparison included operation time, tumor size, pre- and postoperative serum levels of calcium and PTH and length of stay in hospital. Complications were defined as clinical and laboratory signs of hypocalcemia, persistent elevated serum calcium, temporary or persistent recurrent laryngeal nerve paralysis, bleeding with need for reoperation, surgical site infection or need of tracheotomy. Results. Parathyroidectomy alone was performed in 39.2% of patients. In 60.8% partial or total thyroidectomy was conducted simultaneously. More older patients had history of stroke and/or suffered from diabetes. Preoperative serum calcium and PTH did not differ between groups, but older patients displayed higher postoperative serum calcium (p=0.01). No significant differences between the two groups were observed regarding duration of surgery, surgical success rates, postoperative complications and hospitalization time. Conclusions. Even though older patients had more risk factors, our data suggest that there was no difference in surgical management and outcome. Decision for surgical management of pHPT should be done regardless of age

German Bowel Cancer Center: An Attempt to Improve Treatment Quality

Background. Colorectal cancer remains the second most common cause of death from malignancies, but treatment results show high diversity. Certified bowel cancer centres (BCC) are the basis of a German project for improvement of treatment. The aim of this study was to analyze if certification would enhance short-term outcome in rectal cancer surgery. Material and Methods. This quality assurance study included 8197 patients with rectal cancer treated between 1 January 2008 and 31 December 2010. We compared cohorts treated in certified and noncertified hospitals regarding preoperative variables and perioperative outcomes. Outcomes were verified by matched-pair analysis. Results. Patients of noncertified hospitals had higher ASA-scores, higher prevalence of risk factors, more distant metastases, lower tumour localization, lower frequency of pelvic MRI, and higher frequencies of missing values and undetermined TNM classifications (significant differences only). Outcome analysis revealed more general complications in certified hospitals (20.3% versus 17.4%, p=0.03). Both cohorts did not differ significantly in percentage of R0-resections, intraoperative complications, anastomotic leakage, in-hospital death, and abdominal wall dehiscence. Conclusions. The concept of BCC is a step towards improving the structural and procedural quality. This is a good basis for improving outcome quality but cannot replace it. For a primary surgical disease like rectal cancer a specific, surgery-targeted program is still needed