Fungal Community Composition as Affected by Litter Chemistry and Weather during Four Years of Litter Decomposition in Rainshadow Coastal Douglas-Fir Forests.

Climate and litter chemistry are major factors influencing litter decay, a process mediated by microbes, such as fungi, nitrogen-fixing bacteria and ammonia-oxidizing bacteria. Increasing atmospheric CO2 concentrations can decrease nitrogen (N) and increase condensed tannin (CT) content in foliar litter, reducing litter quality and slowing decomposition. We hypothesized that reduced litter quality inhibits microbes and is the mechanism causing decomposition to slow. Litterbags of Douglas-fir needles and poplar leaves with a range of N (0.61-1.57%) and CT (2.1-29.1%) treatment and natural acid unhydrolyzable residue (35.3-41.5%) concentrations were placed along climatic gradients in mature Douglas-fir stands of coastal British Columbia rainshadow forests. The structure (diversity, richness and evenness) and composition of microbial communities were analyzed using DGGE profiles of 18S, NifH-universal and AmoA PCR amplicons in foliar litter after 7, 12, 24 and 43 months of decay. High CT and low N concentrations in leaf litter were associated with changes in microbial community composition, especially fungi. Contrary to our hypothesis, high CT and low N treatments did not inhibit microbial colonization or diversity. The joint effects of air temperature and soil moisture on microbial community composition at our sites were more important than the effects of initial litter chemistry.

Achilles Tendon Rip-Stop SpeedBridge Repair.

Achilles tendon injuries have been on the rise secondary to our increased participation in sports, increase in societal obesity rates, and the growing elderly population. There has been disagreement in recent years about whether to treat injuries such as Achilles tendon ruptures operatively or nonoperatively with aggressive functional rehabilitation. For those opting to surgically manage Achilles tendon ruptures, insertional Achilles tendonitis, or augment the described SpeedBridge Achilles tendon repair, we propose a modified rip-stop technique. The goal of this technique is to provide a biomechanical advantage to our current operative interventions for these injuries, a greater load-to-failure and a speedier, more reliable return to sport in our athletic populations.

Responses of Soil Fungal Populations and Communities to the Thinning of Cryptomeria Japonica Forests.

Forest management activities, such as tree thinning, alter forest ecology, including key components of forest ecosystems, including fungal communities. In the present study, we investigate the effects of forest thinning intensity on the populations and structures of fungal soil communities in the Cryptomeria japonica forests of central Taiwan as well as the dynamics of soil fungi communities in these forests after a thinning disturbance. Although the populations of soil fungi significantly increased in the first 6 months after thinning, these increases had subsided by 9 months. This pulse was attributed to a transient increase in the populations of rapid colonizers. A multiple regression analysis positively correlated fungal populations with organic matter content and cellulase activity. Thinning initially provided large amounts of fresh leaves and roots as nutrient-rich substrates for soil fungi. Denaturing gradient gel electrophoresis (DGGE) profiles indicated that soil fungal communities significantly differed among plots with 0% (control), 25%, and 50% tree thinning in the first 21 months post-thinning, with no significant differences being observed after 21 months. The fungal communities of these forest soils also changed with the seasons, and an interactive relationship was detected between seasons and treatments. Seasonal variations in fungal communities were the most pronounced after 50% tree thinning. The results of the present study demonstrate that the soil fungi of Taiwanese C. japonica forests are very sensitive to thinning disturbances, but recover stability after a relatively short period of time.

Nutrient-cycling microbes in coastal Douglas-fir forests: regional-scale correlation between communities, in situ climate, and other factors.

Microbes such as fungi and bacteria play fundamental roles in litter-decay and nutrient-cycling; however, their communities may respond differently than plants to climate change. The structure (diversity, richness, and evenness) and composition of microbial communities in climate transects of mature Douglas-fir stands of coastal British Columbia rainshadow forests was analyzed, in order to assess in situ variability due to different temperature and moisture regimes. We compared denaturing gradient gel electrophoresis profiles of fungi (18S-FF390/FR1), nitrogen-fixing bacteria (NifH-universal) and ammonia-oxidizing bacteria (AmoA) polymerase chain reaction amplicons in forest floor and mineral soil samples from three transects located at different latitudes, each transect spanning the Coastal Western Hemlock and Douglas-fir biogeoclimatic zones. Composition of microbial communities in both soil layers was related to degree days above 0°C (2725-3489), while pH (3.8-5.5) best explained shifts in community structure. At this spatial scale, climatic conditions were likely to directly or indirectly select for different microbial species while local site heterogeneity influenced community structure. Significant changes in microbial community composition and structure were related to differences as small as 2.47% and 2.55°C in mean annual moisture and temperature variables, respectively. The climatic variables best describing microbial composition changed from one functional group to the next; in general they did not alter community structure. Spatial distance, especially associated with latitude, was also important in accounting for community variability (4-23%); but to a lesser extent than the combined influence of climate and soil characteristics (14-25%). Results suggest that in situ climate can independently account for some patterns of microbial biogeography in coastal Douglas-fir forests. The distribution of up to 43% of nutrient-cycling microorganisms detected in forest soils responded to smaller abiotic gradients than host trees.

No difference in 90-day complications between bilateral unicompartmental and total knee arthroplasty.

This study compares the 90-day complication rate of 28 patients who underwent simultaneous bilateral unicompartmental knee arthroplasty (UKA) with a matched control group of 56 patients who underwent simultaneous total knee arthroplasty (TKA.) We matched the groups 2:1 for age, gender, and American Society of Anesthesiologists scores and reviewed their medical records to identify complications, reoperations, and hospital readmission during the first 90 days after surgery as well as the operative times and length of hospital stay. The bilateral UKA group had shorter operative times (P = 0.06) and shorter length of hospital stay (P < 0.001). Ninety-day complications in the UKA group included 1 wound infection and 1 deep vein thrombosis (3.57%). The TKA group had 2 complications including 1 superficial wound infection and 1 pulmonary embolism (1.79%) (P = 0.60). One knee in each group required irrigation and debridement for wound infection. These patients requiring additional surgery for wound infection were the only 2 patients that required readmission within 90 days. Despite being a less invasive procedure, we found that the bilateral UKA group had a similar risk of complications to a matched group of bilateral TKA patients.

The effects of high-tannin leaf litter from transgenic poplars on microbial communities in microcosm soils.

The impacts of leaf litter from genetically modified hybrid poplar accumulating high levels of condensed tannins (proanthocyanidins) were examined in soil microcosms consisting of moss growing on sieved soil. Moss preferentially proliferated in microcosms with lower tannin content; DGGE (denaturing gradient gel electrophoresis) detected increased fungal diversity in microcosms with low-tannin litter. The proportion of cloned rDNA sequences from Actinobacteria decreased with litter addition while Bacteroidetes, Chloroflexi, Cyanobacteria, and α-Proteobacteria significantly increased. ß-Proteobacteria were proportionally more numerous at high-tannin levels. Tannins had no significant impact on overall diversity of bacterial communities analyzed with various estimators. There was an increased proportion of N-fixing bacteria corresponding to the addition of litter with low-tannin levels. The addition of litter increased the proportion of Ascomycota/Basidiomycota. Dothideomycetes, Pucciniomycetes, and Tremellomycetes also increased and Agaricomycetes decreased. Agaricomycetes and Sordariomycetes were significantly more abundant in controls, whereas Pucciniomycetes increased in soil with litter from transformed trees (P = 0.051). Richness estimators and diversity indices revealed no significant difference in the composition of fungal communities; PCoA (principal coordinate analyses) partitioned the fungal communities into three groups: (i) those with higher amounts of added tannin from both transformed and untransformed treatments, (ii) those corresponding to soils without litter, and (iii) those corresponding to microcosms with litter added from trees transformed only with a ß-glucuronidase control vector. While the litter from transformed poplars had significant effects on soil microbe communities, the observed impacts reflected known impacts on soil processes associated with tannins, and were similar to changes that would be expected from natural variation in tannin levels.

Salvage of angioplasty failures and complications in hemodialysis arteriovenous access using the FLUENCY Plus Stent Graft: technical and 180-day patency results.

PURPOSE: To review technical and 180-day clinical outcomes when stent grafts were used to treat dysfunctional arteriovenous (AV) hemodialysis access circuits. MATERIALS AND METHODS: The FLUENCY Plus Stent Graft (Bard Peripheral Vascular, Tempe, Arizona) was used to salvage percutaneous transluminal angioplasty (PTA) technical failures and complications in AV access circuits over 2 years. There were 106 patients treated with 138 stent grafts. Indications for stent graft use included residual stenosis after PTA (n = 81), extravasation after PTA (n = 22), early recurrent stenosis (n = 14), pseudoaneurysms (n = 4), and "other" (n = 4). Data were retrospectively analyzed for complications and outcomes. RESULTS: Technical success was achieved in all patients, and clinical success was achieved in 104 (98%) of 106 patients. At 180 days, postintervention primary patency (PIPP) was 47%, and postintervention secondary patency (PISP) was 79%. PIPP was 62% for autogenous fistulas (AVFs) and 35% for prosthetic grafts (AVGs) (P = .010). The 180-day PIPP for stent grafts 9-10 mm in diameter was 63% versus 38% for stent grafts 6-8 mm in diameter (P = .012). Implants that did not cross the elbow had a 180-day PIPP of 47% compared with 25% for implants across the elbow (P = .032). Technical complications were periprocedure AVG thromboses (n = 2), intraprocedural stent graft dislodgment (n = 1), venospasm (n = 2), and contrast agent-related hives (n = 1). One patient returned at 2 months with an infected AVG and stent graft in the outflow vein. CONCLUSIONS: The FLUENCY Plus Stent Graft was effective for maintenance of hemodialysis access circuit patency and was comparable or better than historical outcomes for PTA and bare stents. Factors that favored improved patency included larger diameter devices, use in AVFs, and avoiding placement across the elbow joint.

Quantification of nitrogen reductase and nitrite reductase genes in soil of thinned and clear-cut Douglas-fir stands by using real-time PCR.

The abundance of nifH, nirS, and nirK gene fragments involved in nitrogen (N) fixation and denitrification in thinned second-growth Douglas-fir (Pseudotsuga menziesii subsp. menziesii [Mirb.] Franco) forest soil was investigated by using quantitative real-time PCR. Prokaryotic N cycling is an important aspect of N availability in forest soil. The abundance of universal nifH, Azotobacter sp.-specific nifH (nifH-g1), nirS, and nirK gene fragments in unthinned control and 30, 90, and 100% thinning treatments were compared at two long-term research sites on Vancouver Island, Canada. The soil was analyzed for organic matter (OM), total carbon (C), total N, NH4-N, NO3-N, and phosphorus (P). The soil horizon accounted for the greatest variation in nutrient status, followed by the site location. The 30% thinning treatment was associated with significantly greater nifH-g1 abundance than the control treatment in one site; at the same site, nirS in the mineral soil horizon was significantly reduced by thinning. The abundance of nirS genes significantly correlated with the abundance of nirK genes. In addition, significant correlations were observed between nifH-g1 abundance and C and N in the organic horizon and between nirS and nirK and N in the mineral horizon. Overall, no clear influence of tree thinning on nifH, nirS, and nirK was observed. However, soil OM, C, and N were found to significantly influence N-cycling gene abundance.

Expanded polytetrafluoroethylene-covered stent treatment of angioplasty-related extravasation during hemodialysis access intervention: technical and 180-day patency.

PURPOSE: To review technical and patency results with expanded polytetrafluoroethylene (ePTFE)-covered stents for treatment of venous rupture encountered during percutaneous hemodialysis intervention. MATERIALS AND METHODS: The Fluency covered stent is a tracheobronchial device that was used in an off-label manner to treat percutaneous transluminal angioplasty (PTA)-induced rupture in hemodialysis circuits. Data were retrospectively reviewed for all patients treated with the stent in 2004-2005 at two medical centers for PTA-related rupture. RESULTS: From a database of 106 procedures, 21 patients (21 procedures) were treated with the ePTFE-covered stent for PTA-related extravasation. Nine patients had arteriovenous (AV) grafts and 12 had AV fistulas. Five extravasations followed angioplasty as part of an AV graft declotting procedure. Location of extravasation was the outflow or cannulation venous segment (n = 11), cephalic arch (n = 3), AV graft venous anastomosis (n = 6), and intragraft (n = 1). All procedures were technically successful at halting extravasation and preserving vascular access. There were no known complications, and all patients underwent a successful first dialysis session. Twenty of the 21 circuits remained patent beyond the first week after intervention. The 180-day primary circuit patency rate was 20% and the 180-day cumulative circuit patency rate was 65%. CONCLUSIONS: In 21 patients, the ePTFE-covered stent successfully treated PTA-induced rupture with no need for acute secondary procedures such as thrombolysis or surgery. There was no instance of pseudoaneurysm formation or delayed bleeding. The ePTFE-covered stent offers advantages compared to prolonged PTA or bare stents when attempting to preserve hemodialysis access after PTA-induced rupture.

Cultural studies of Morchella elata.

The in vitro growth of Morchella elata was characterized with respect to the effects of a variety of substrates, isolates, developmental status of the parental ascoma, temperature, and pH. Optimal substrates for growth included sucrose, mannose and lactose, but the growth of some isolates was substantially reduced in some composite media. Maltose and potato-dextrose media limited growth and caused changes in colony morphology; mycelial pigmentation was black in the case of maltose, and mycelial margins were plumose in potato-dextrose cultures. Rapid growth was most reliably achieved in a composite medium containing 1:1 sucrose:mannose. Isolates derived from single ascospores shortly after ejection from ascomata varied in ability to grow in the various substrates. This may be related to variable maturity or dormancy; increasing growth rates correlated with pileus length in the parental ascomata, and ascomata that initially produced slower-growing or abortive colonies produced faster-growing colonies after storage at 20 degrees C for 96 wk. The growth of M. elata derived from recently ejected ascospores was optimal at 16-24 degrees C or above for a faster-growing isolate, and 20-24 degrees C or above for a slow-growing isolate. Although neither isolate grew at 8 degrees C or below in an initial experiment, spawn cultured on puffed wheat at 28 degrees C produced mycelia that proliferated when transferred to soil media and incubated at 8 degrees C. Growth of M. elata in liquid cultures adjusted with potassium hydroxide was optimal at pH 7.0, and was relatively sensitive to more acidic or alkaline pH. When calcium carbonate was used to adjust pH, optimal growth shifted to pH 7.7 or above, suggesting that wood ash and other calcium compounds may not only stimulate growth in natural settings, but also alter the optimal pH for proliferation of M. elata. Further studies with other substrate combinations and incubation conditions will be necessary to fully understand the connections between in vitro growth and the ecological behaviour of the fungus.