Leveraging a Landscape-Level Monitoring and Assessment Program for Developing Resilient Shorelines throughout the Laurentian Great Lakes

Traditionally, ecosystem monitoring, conservation, and restoration have been conducted in a piecemeal manner at the local scale without regional landscape context. However, scientifically driven conservation and restoration decisions benefit greatly when they are based on regionally determined benchmarks and goals. Unfortunately, required data sets rarely exist for regionally important ecosystems. Because of early recognition of the extreme ecological importance of Laurentian Great Lakes coastal wetlands, and the extensive degradation that had already occurred, significant investments in coastal wetland research, protection, and restoration have been made in recent decades and continue today. Continued and refined assessment of wetland condition and trends, and the evaluation of restoration practices are all essential to ensuring the success of these investments. To provide wetland managers and decision makers throughout the Laurentian Great Lakes basin with the optimal tools and data needed to make scientifically-based decisions, our regional team of Great Lakes wetland scientists developed standardized methods and indicators used for assessing wetland condition. From a landscape perspective, at the Laurentian Great Lakes ecosystem scale, we established a stratified random-site-selection process to monitor birds, anurans, fish, macroinvertebrates, vegetation, and physicochemical conditions of coastal wetlands in the US and Canada. Monitoring of approximately 200 wetlands per year began in 2011 as the Great Lakes Coastal Wetland Monitoring Program. In this paper, we describe the development, delivery, and expected results of this ongoing international, multi-disciplinary, multi-stakeholder, landscape-scale monitoring program as a case example of successful application of landscape conservation design.

Global patterns in the metacommunity structuring of lake macrophytes: regional variations and driving factors

We studied community-environment relationships of lake macrophytes at two metacommunity scales using data from 16 regions across the world. More specifically, we examined (a) whether the lake macrophyte communities respond similar to key local environmental factors, major climate variables and lake spatial locations in each of the regions (i.e., within-region approach) and (b) how well can explained variability in the community-environment relationships across multiple lake macrophyte metacommunities be accounted for by elevation range, spatial extent, latitude, longitude, and age of the oldest lake within each metacommunity (i.e., across-region approach). In the within-region approach, we employed partial redundancy analyses together with variation partitioning to investigate the relative importance of local variables, climate variables, and spatial location on lake macrophytes among the study regions. In the across-region approach, we used adjusted R2 values of the variation partitioning to model the community-environment relationships across multiple metacommunities using linear regression and commonality analysis. We found that niche filtering related to local lake-level environmental conditions was the dominant force structuring macrophytes within metacommunities. However, our results also revealed that elevation range associated with climate (increasing temperature amplitude affecting macrophytes) and spatial location (likely due to dispersal limitation) was important for macrophytes based on the findings of the across-metacommunities analysis. These findings suggest that different determinants influence macrophyte metacommunities within different regions, thus showing context dependency. Moreover, our study emphasized that the use of a single metacommunity scale gives incomplete information on the environmental features explaining variation in macrophyte communities.

The science-policy interface of risk-based freshwater and marine management systems: From concepts to practical tools

Maintaining the current state of ecosystem services from freshwater and marine ecosystems around the world is at risk. Cumulative effects of multiple human pressures on ecosystem components and functions are indicative of residual pressures that "fall through" the cracks of current industry sector management practices. Without an understanding of the level of residual pressures generated by these measures, we are unlikely to reconcile the root causes of ecosystem effects to improve these management practices to reduce their residual pressures. In this paper, we present a new modelling framework that combines a qualitative and quantitative assessments of the effectiveness of the measures used in the daily operations of industry sectors to predict their residual pressure that is delivered to the ecosystem. The predicted residual pressure can subsequently be used as an input variable for ecosystem models. We combine the Bow-tie analysis of the measures with a Bayesian belief network to quantify the effectiveness of the measures and predict the residual pressures.

An expanded fish-based index of biotic integrity for Great Lakes coastal wetlands

Biotic indicators are useful for assessing ecosystem health because the structure of resident communities generally reflects abiotic conditions integrated over time. We used fish data collected over 5 years for 470 Great Lakes coastal wetlands to develop multi-metric indices of biotic integrity (IBI). Sampling and IBI development were stratified by vegetation type within each wetland to account for differences in physical habitat. Metrics were evaluated against numerous indices of anthropogenic disturbance derived from water quality and surrounding land-cover variables. Separate datasets were used for IBI development and testing. IBIs were composed of 10-11 metrics for each of four vegetation types (bulrush, cattail, water lily, and submersed aquatic vegetation). Scores of all IBIs correlated well with disturbance indices using the development data, and the accuracy of our IBIs was validated using the testing data. Our fish IBIs can be used to prioritize wetland protection and restoration efforts across the Great Lakes basin. The IBIs will also be useful in monitoring programs mandated by the Agreement between Canada and the United States of America on Great Lakes Water Quality, such as for assessing Beneficial Use Impairments (BUIs) in Great Lakes Areas of Concern, and in other ecosystem management programs in Canada and the USA.

Pathways and places associated with nonindigenous aquatic species introductions in the Laurentian Great Lakes

Propagule pressure (i.e., the frequency and abundance of introductions) is a common indicator of the likelihood of nonindigenous aquatic species (NAS) establishment success. Evaluating propagule pressure associated with multiple introduction pathways relative to present NAS distribution patterns may identify which pathway presents the greatest risk. Our objective was to develop and evaluate three geospatial metrics for the Laurentian Great Lakes as proxies of propagule pressure associated with three major introduction pathways: maritime commerce, organisms in trade, and water recreation. Logistic and linear regression analyses were conducted between NAS presence and introduction pathway intensity (e.g., number of vessel trips received by a port) for 23 NAS over a five-decade period (1970 - 2013). Notably, city population size was the best predictor of NAS presence, even for NAS introduced through ballast water discharge. Moreover, through time, city population size was an increasingly significant predictor of the presence of organisms in trade, signaling a change in both the types of organisms introduced and places where introductions are occurring. Nonetheless, all three metrics are reasonable proxies for propagule pressure and as such are applicable for risk assessment, monitoring, and control strategies.

Pseudosyndactyly and Musculoskeletal Contractures in Inherited Epidermolysis Bullosa: Experience of the National Epidermolysis Bullosa Registry, 1986–2002

Mitten deformities of the hands and feet occur in nearly every patient with the most severe subtype (Hallopeau-Siemens) of recessive dystrophic epidermolysis bullosa, and in at least 40–50% of all other recessive dystrophic epidermolysis bullosa patients. Smaller numbers of patients with dominant dystrophic, junctional, and simplex types of epidermolysis bullosa are also at risk of this complication. Surgical intervention is commonly performed to correct these deformities, but recurrence and the need for repeated surgery are common. Higher numbers of epidermolysis bullosa patients also develop musculoskeletal contractures in other anatomic sites, further impairing overall function. Lifetable analyses not only better project the cumulative risk of mitten deformities and other contractures but also emphasize the need for early surveillance and intervention, since both of these musculoskeletal complications may occur within the first year of life.

Eating disorder professionals' perceptions of oral health knowledge

OBJECTIVE

The aim of this study was to assess the oral health knowledge among professionals who specialize in treating eating disorders, and identify to what extent their education, and training addresses oral health care delivery, and recommendations for individuals with eating disorders.

METHOD

Participants for this study were licensed behavioural and medical providers specializing in eating disorder treatment (n = 107), and recruited through professional eating disorder organizations. Participants completed an anonymous, online questionnaire (33 items) assessing level of oral health-related education, knowledge and treatment recommendations within the participant's respective eating disorder discipline.

RESULTS

The majority of respondents (85%) were formally trained in eating disorders, and of those trained, 64.4% were not satisfied with the level of oral health education during formal education, and 19.5% report no oral health education. Respondents consider their knowledge of risk of oral disease for their clients/patients as average or above (84%), and ranked tooth erosion as the greatest reason for oral care (63%) while dry mouth led in the rankings for least significant reason for oral care (33%). Referral for oral care was found to be more common after reports of complication (55%).

DISCUSSION

According to these findings, eating disorder professionals regard oral health care for their clients as significant, and may be unaware of associated oral risk factors, current oral care standards and long-term oral effects of disordered eating apart from enamel erosion.

Disease risk in a dynamic environment: the spread of tick-borne pathogens in Minnesota, USA

As humans and climate change alter the landscape, novel disease risk scenarios emerge. Understanding the complexities of pathogen emergence and subsequent spread as shaped by landscape heterogeneity is crucial to understanding disease emergence, pinpointing high-risk areas, and mitigating emerging disease threats in a dynamic environment. Tick-borne diseases present an important public health concern and incidence of many of these diseases are increasing in the United States. The complex epidemiology of tick-borne diseases includes strong ties with environmental factors that influence host availability, vector abundance, and pathogen transmission. Here, we used 16 years of case data from the Minnesota Department of Health to report spatial and temporal trends in Lyme disease (LD), human anaplasmosis, and babesiosis. We then used a spatial regression framework to evaluate the impact of landscape and climate factors on the spread of LD. Finally, we use the fitted model, and landscape and climate datasets projected under varying climate change scenarios, to predict future changes in tick-borne pathogen risk. Both forested habitat and temperature were important drivers of LD spread in Minnesota. Dramatic changes in future temperature regimes and forest communities predict rising risk of tick-borne disease.

Autotransplantation of solitary kidney with renal artery aneurysm treated with laparoscopic nephrectomy and ex vivo repair: a case report

INTRODUCTION

Renal artery aneurysms (RAA) are extremely rare clinical entities with associated morbidities including hypertension and rupture. Although most RAA can be treated with in vivo repair or endovascular techniques, these may not be possible in patients with complex RAA beyond the renal artery bifurcation. We report a case of RAA in a patient with a solitary kidney that we treated successfully by extracorporeal repair and autotransplantation and the 2-years follow-up.

CASE REPORT

A 64-year-old woman with a history of right nephrectomy for renal cell carcinoma presented with RAA found on routine computed tomography (CT). Preoperative workup demonstrated a 2.2 × 2.1 × 3-cm aneurysm in the distal left renal artery that was not amendable to in vivo or endovascular repair. The patient underwent a laparoscopic-assisted left nephrectomy, ex vivo renal artery aneurysm repair, and autotransplantation. She did well postoperatively and in clinic follow-up was found to have a creatinine of 1.2 mg/dL at the end of 2 years and stable blood pressure control.

DISCUSSION

This patient with RAA in her solitary kidney was successfully treated with laparoscopic-assisted nephrectomy, ex vivo repair, and autotransplantation. Her creatinine was stable postoperatively despite absence of a second kidney.

Effects of wetland vs. landscape variables on parasite communities of Rana pipiens: links to anthropogenic factors

The emergence of several diseases affecting amphibian populations worldwide has prompted investigations into determinants of the occurrence and abundance of parasites in frogs. To understand the spatial scales and identify specific environmental factors that determine risks of parasitism in frogs, helminth communities in metamorphic frogs of the northern leopard frog (Rana pipiens) were examined in relation to wetland and landscape factors at local (1 km) and regional (10 km) spatial extents in an agricultural region of Minnesota (USA) using regression analyses, ordination, and variance partitioning techniques. Greater amounts of forested and woody wetland habitats, shorter distances between woody wetlands, and smaller-sized open water patches in surrounding landscapes were the most consistently positive correlates with the abundances, richness, and diversity of helminths found in the frogs. Wetland and local landscape variables were suggested as most important for larval trematode abundances, whereas local and regional landscape variables appeared most important for adult helminths. As previously reported, the sum concentration of atrazine and its metabolite desethylatrazine, was the strongest predictor of larval trematode communities. In this report, we highlight the additional influences of landscape factors. In particular, our data suggest that anthropogenic activities that have resulted in the loss of the availability and connectivity of suitable habitats in the surrounding landscapes of wetlands are associated with declines in helminth richness and abundance, but that alteration of wetland water quality through eutrophication or pesticide contamination may facilitate the transmission of certain parasite taxa when they are present at wetlands. Although additional research is needed to quantify the negative effects of parasitism on frog populations, efforts to reduce inputs of agrochemicals into wetlands to limit larval trematode infections may be warranted, given the current high rates of amphibian declines and extinction events.

Liver transplantation in the United States, 1999-2008

Changes in organ allocation policy in 2002 reduced the number of adult patients on the liver transplant waiting list, changed the characteristics of transplant recipients and increased the number of patients receiving simultaneous liver-kidney transplantation (SLK). The number of liver transplants peaked in 2006 and declined marginally in 2007 and 2008. During this period, there was an increase in donor age, the Donor Risk Index, the number of candidates receiving MELD exception scores and the number of recipients with hepatocellular carcinoma. In contrast, there was a decrease in retransplantation rates, and the number of patients receiving grafts from either a living donor or from donation after cardiac death. The proportion of patients with severe obesity, diabetes and renal insufficiency increased during this period. Despite increases in donor and recipient risk factors, there was a trend towards better 1-year graft and patient survival between 1998 and 2007. Of major concern, however, were considerable regional variations in waiting time and posttransplant survival. The current status of liver transplantation in the United States between 1999 and 2008 was analyzed using SRTR data. In addition to a general summary, we have included a more detailed analysis of liver transplantation for hepatitis C, retransplantation and SLK transplantation.

Effect of time after transplantation on microbiology of urinary tract infections among renal transplant recipients

We evaluated the microbiology of renal transplant recipients hospitalized with urinary tract infections over a 10-year period. While gram-negative organisms were seen most frequently (73%), the median time to infection post transplantation was shorter in patients infected with gram-positive organisms (9.0 vs. 44.7 months).

Hepatocellular stem cells

The liver has enormous regenerative capacity. Restitution of the liver in response to different injuries involves proliferation of cells at different levels of liver lineage. Mature hepatocytes, which are normally dormant, could undergo rapid replication with a near infinite capacity to proliferate. When the replication of mature hepatocytes is inhibited, a reserve compartment of bipotential hepatic progenitor/stem cells is activated. The degree of activation appears to correlate with the degree of inflammation and stage of chronic liver disease. Deregulation of key regulatory signaling pathways such as transforming growth factor-beta, Wnt, hepatocyte growth factor, insulin-like growth factor, transforming growth factor-alpha and epidermal growth factor in this progenitor/stem cell population could give rise to HCC. Further understanding of these key signaling pathways and the molecular and genetic alterations associated with HCC could provide major advances in new therapeutic and diagnostic modalities.

Disruption of transforming growth factor-beta signaling through beta-spectrin ELF leads to hepatocellular cancer through cyclin D1 activation

Transforming growth factor-beta (TGF-beta) signaling members, TGF-beta receptor type II (TBRII), Smad2, Smad4 and Smad adaptor, embryonic liver fodrin (ELF), are prominent tumor suppressors in gastrointestinal cancers. Here, we show that 40% of elf(+/-) mice spontaneously develop hepatocellular cancer (HCC) with markedly increased cyclin D1, cyclin-dependent kinase 4 (Cdk4), c-Myc and MDM2 expression. Reduced ELF but not TBRII, or Smad4 was observed in 8 of 9 human HCCs (P<0.017). ELF and TBRII are also markedly decreased in human HCC cell lines SNU-398 and SNU-475. Restoration of ELF and TBRII in SNU-398 cells markedly decreases cyclin D1 as well as hyperphosphorylated-retinoblastoma (hyperphosphorylated-pRb). Thus, we show that TGF-beta signaling and Smad adaptor ELF suppress human hepatocarcinogenesis, potentially through cyclin D1 deregulation. Loss of ELF could serve as a primary event in progression toward a fully transformed phenotype and could hold promise for new therapeutic approaches in human HCCs.

Integrated measures of anthropogenic stress in the U.S. Great lakes basin

Integrated, quantitative expressions of anthropogenic stress over large geographic regions can be valuable tools in environmental research and management. Despite the fundamental appeal of a regional approach, development of regional stress measures remains one of the most important current challenges in environmental science. Using publicly available, pre-existing spatial datasets, we developed a geographic information system database of 86 variables related to five classes of anthropogenic stress in the U.S. Great Lakes basin: agriculture, atmospheric deposition, human population, land cover, and point source pollution. The original variables were quantified by a variety of data types over a broad range of spatial and classification resolutions. We summarized the original data for 762 watershed-based units that comprise the U.S. portion of the basin and then used principal components analysis to develop overall stress measures within each stress category. We developed a cumulative stress index by combining the first principal component from each of the five stress categories. Maps of the stress measures illustrate strong spatial patterns across the basin, with the greatest amount of stress occurring on the western shore of Lake Michigan, southwest Lake Erie, and southeastern Lake Ontario. We found strong relationships between the stress measures and characteristics of bird communities, fish communities, and water chemistry measurements from the coastal region. The stress measures are taken to represent the major threats to coastal ecosystems in the U.S. Great Lakes. Such regional-scale efforts are critical for understanding relationships between human disturbance and ecosystem response, and can be used to guide environmental decision-making at both regional and local scales.

Impact of initial antibiotic choice and delayed appropriate treatment on the outcome of Staphylococcus aureus bacteremia

The study presented here investigated the impact of initial antibiotic choice (beta-lactams vs vancomycin) on the outcome of 342 patients with Staphylococcus aureus bacteremia (50.9% with methicillin-resistant isolates) encountered between 1 January 2002 and 30 June 2003. Initial antibiotics were inappropriate (beta-lactams) in 60 (34.5%) methicillin-resistant cases and suboptimal (vancomycin) in 62 (36.9%) methicillin-susceptible cases. Time to effective antibiotic therapy was longer in methicillin-resistant cases (25.5+/-28.6 vs 9.6+/-16.6 h; p<0.0005). All-cause in-hospital mortality was higher with inappropriate therapy (35.0 vs 20.9%; p=0.02). Initial vancomycin treatment was associated with a higher incidence of delayed clearance (>or=3 days) of methicillin-susceptible bacteremia (56.3 vs 37.0%; p=0.03). The results indicate inappropriate initial therapy is associated with higher in-hospital mortality and initial vancomycin may delay clearance.

Impact of inherited epidermolysis bullosa on parental interpersonal relationships, marital status and family size

BACKGROUND

The presence in a family of a child or children with epidermolysis bullosa (EB) may have profound psychological implications for other family members.

OBJECTIVES

To assess the impact of the presence of EB in one or more children on the personal relationships between their parents.

METHODS

Standardized questionnaires were used.

RESULTS

In general, the presence of a child severely affected with EB had profound effects on many aspects of marriage. This included a lack of interest in participating in activities as couples [junctional EB (JEB), 45%; recessive dystrophic EB (RDEB), 25%], a lack of energy to invest in such pursuits (JEB, 82%; RDEB, 50%), limitations in opportunities for sharing nonintimate physical activities (reported by most parents having children with some type of generalized EB), and negatively altered parental sex life (JEB, 55%; RDEB, 39%). This is consistent with the fact that 10%, 64%, 25% and 36% of parents of an affected child with EB simplex (EBS), JEB, dominant dystrophic EB (DDEB) and RDEB, respectively, characterized their relationships as couples as revolving almost exclusively around the day-to-day care of their affected children. The severity of disease in an affected child clearly influenced parental decisions about having more children: 24% and 64% of parents of children with JEB and RDEB, respectively, chose not to have additional children, compared with 26% and 54% of parents with children having EBS or DDEB. This choice was most often pursued via tubal ligation; less often, alternative means of surgical sterilization were chosen. Divorce was common among parents of children with EB (range: 17% in EBS to 31% in JEB) and, with the exception of parents of children with EBS, was usually directly attributed by one or both parents to the profound impact that this disease had exerted on their marriage.

CONCLUSIONS

Physicians caring for children with EB need to give more consideration to the many psychological factors that may contribute to their patients' well being. They may need to assist these children's parents in seeking support and counselling to prevent destruction of the family unit.

Environmentally stratified sampling design for the development of Great Lakes environmental indicators

Understanding the relationship between human disturbance and ecological response is essential to the process of indicator development. For large-scale observational studies, sites should be selected across gradients of anthropogenic stress, but such gradients are often unknown for apopulation of sites prior to site selection. Stress data available from public sources can be used in a geographic information system (GIS) to partially characterize environmental conditions for large geographic areas without visiting the sites. We divided the U.S. Great Lakes coastal region into 762 units consisting of a shoreline reach and drainage-shed and then summarized over 200 environmental variables in seven categories for the units using a GIS. Redundancy within the categories of environmental variables was reduced using principal components analysis. Environmental strata were generated from cluster analysis using principal component scores as input. To protect against site selection bias, sites were selected in random order from clusters. The site selection process allowed us to exclude sites that were inaccessible and was shown to successfully distribute sites across the range of environmental variation in our GIS data. This design has broad applicability when the goal is to develop ecological indicators using observational data from large-scale surveys.

Assessment of mobility, activities and pain in different subtypes of epidermolysis bullosa

A standardized questionnaire was used to assess mobility, activity and pain in 140 randomly chosen children, who were representative of all major types and subtypes of inherited epidermolysis bullosa (EB). Pain status in these children was compared with 374 randomly selected adults with EB. The level of independence for each of six activities of daily living (ADL) (toileting; feeding; bathing; dressing; grooming; walking) was assessed in these EB children using conventional criteria for scoring. Whereas more than 90% of all EB simplex (EBS) and dominant dystrophic EB (DDEB) children were totally independent for each function (excluding walking), the frequency of similarly totally independent patients with junctional EB (JEB) and recessive dystrophic EB (RDEB) ranged from only 39% to 73%. No DDEB children and only 2% of EBS patients were totally dependent in their individual ADL, in comparison to 8-27% of JEB and 2-27% of RDEB children. Totally independent walking was reported in only 31%, 31%, 67%, and 24% of EBS, JEB, DDEB, and RDEB children, respectively. A daily level of EB-related pain was assessed in children by their parents using a linear scale of 0 (no pain) to 10 (unbearable pain). Whereas 14-19% of all children with EBS, JEB, and DDEB were graded with pain levels of more than 5, 32% of all RDEB children reportedly suffered this much pain. Increased frequencies of pain with scores more than 5 were most often noted in those patients having more clinically extensive or severe EB subtypes. These included JEB-Herlitz (20% vs. 14% in JEB-non-Herlitz) and RDEB-Hallopeau-Siemens (47% vs. 20% in all other RDEB subtypes). Only 5% of all RDEB children reportedly were pain-free, compared to 12-14% of those with EBS, JEB, and DDEB. Collectively, these data provide the first report of the specific impact different forms of EB have on daily living and coping with this genodermatosis.

Prevalence of skeletal and eye malformations in frogs from north-central United States: estimations based on collections from randomly selected sites

Skeletal malformation rates for several frog species were determined in a set of randomly selected wetlands in the north-central USA over three consecutive years. In 1998, 62 sites yielded 389 metamorphic frogs, nine (2.3%) of which had skeletal or eye malformations. A subset of the original sites was surveyed in the following 2 yr. In 1999, 1,085 metamorphic frogs were collected from 36 sites and 17 (1.6%) had skeletal or eye malformations, while in 2000, examination of 1,131 metamorphs yielded 16 (1.4%) with skeletal or eye malformations. Hindlimb malformations predominated in all three years, but other abnormalities, involving forelimb, eye, and pelvis were also found. Northern leopard frogs (Rana pipiens) constituted the majority of collected metamorphs as well as most of the malformed specimens. However, malformations were also noted in mink frogs (R. septentrionalis), wood frogs (R. sylvatica), and gray tree frogs (Hyla spp.). The malformed specimens were found in clustered sites in all three years but the cluster locations were not the same in any year. The malformation rates reported here are higher than the 0.3% rate determined for metamorphic frogs collected from similar sites in Minnesota in the 1960s, and thus, appear to represent an elevation of an earlier baseline malformation rate.

Assessment of the risk of solar ultraviolet radiation to amphibians. II. In situ characterzation of exposure in amphibian habitats

Ultraviolet B (UVB) radiation has been hypothesized as a potential cause of amphibian population declines and increased incidence of malformations. Realistic studies documenting UV irradiance or dose have rarely been conducted in wetlands used by amphibians. Our data indicates that 99% of UVB is attenuated in the top 5-20 cm of wetlands in our study region (northern Minnesota and Wisconsin). Furthermore, vegetation and other habitat features have substantial impacts on local UVB irradiance levels and dose. UVB attenuation in the water columns of our wetlands is controlled by the specific absorption of dissolved organic carbon (DOC), and consequently, UVB attenuation is best predicted by simple laboratory absorbance measurements such as bulk water color (absorbance at 440 nm) or wavelength-specific absorbance coefficients. Seasonal data indicate thatthe UVB absorption by early and mid-season DOC is higher than that of late summer and fall DOC, suggesting increased protection from UVB during the potentially sensitive stages of amphibian development. In addition to dissolved components, our model indicates that suspended solids play a small role in UVB attenuation in our wetlands but apparently only at high concentrations. Models predicting UV attenuation in wetlands should be used cautiously and should consider temporal variability, given the volatility and dynamic nature of water column characteristics in wetlands. Organism behavior is a critical but poorly understood phenomenon that must be addressed for development of an accurate UV exposure risk model for amphibians.

Pharmacokinetics and biochemical effects of hepapoietin in patients with chronic liver disease

BACKGROUND

Hepapoietin is a naturally occurring cytokine that promotes hepatocyte growth. Animal studies have suggested that hepapoietin and hepatocyte growth factor have a potential role in the prevention and management of liver diseases. However, human studies have been lacking.

AIM

To evaluate the safety and pharmacokinetics of single escalating doses of hepapoietin in patients with chronic liver disease.

METHODS

An open-label, single escalating dose trial with five different doses of hepapoietin (1, 3, 10, 30 and 100 mg) was performed. Adults with chronic, compensated, non-viral liver disease were included. Liver function tests were obtained before dosing, 24 h after hepapoietin administration and on days 4, 7, 30 and 45. All patients were followed for 45 days.

RESULTS

Twenty-five subjects received hepapoietin, with five subjects each at 1, 3, 10, 30 and 100 mg of hepapoietin. Significant decreases occurred in total bilirubin, ammonia, partial thromboplastin time and cholesterol levels overall, and both high-density and low-density lipoprotein cholesterol showed a downward trend. An increase in albumin was observed at the 30 mg dose level. Slight decreases in haemoglobin and red blood cell levels were observed at day 4, but returned to normal levels immediately thereafter. Child-Pugh scores from day 0 to day 7 were improved in 24%, stable in 64% and worse in 12% of patients. Hepatic encephalopathy displayed changes from day 0 to day 45 with improvement in 16%, no change in 80% and worsening in 4%.

CONCLUSIONS

Hepapoietin in doses up to 100 mg is safe for use in humans. Potential benefits are suggested by significant decreases in bilirubin, ammonia, partial thromboplastin time and cholesterol levels and an increase in albumin. Further studies with multiple dosing regimens are needed to identify the clinical utility of hepapoietin in the management of chronic liver disease.

Molecular analysis of coagulase-negative Staphylococcus isolates from blood cultures: prevalence of genotypic variation and polyclonal bacteremia

Fifty-seven coagulase-negative Staphylococcus isolates from 22 inpatients who had > or =2 blood cultures that were positive for Staphylococcus within 24 hours were analyzed to determine the frequency of polyclonal bacteremia. Patients were considered to have bacteremia (14 patients) or contamination of sample (8 patients) on the basis of clinical criteria. Nine colonies were randomly selected from each blood culture and genotyped by means of SmaI digestion/pulsed-field gel electrophoresis. Relatedness was determined by calculation of the Dice coefficient of banding-pattern similarity (S(AB)). Analysis of bacteremic isolates demonstrated the presence of a single species in 35 of 41 blood cultures, 1 related variant in 5 blood cultures (87%-92% S(AB)), and an unrelated strain in 1 blood culture (79% S(AB)). Analysis of contaminated samples demonstrated the presence of a single strain in 10 of 16 blood cultures and 1-3 variants (28%-97% S(AB)) in the remainder. Genotype diversity was significantly more common in the contaminated samples (P=.036). Almost all coagulase-negative Staphylococcus bacteremias were monoclonal.

Transplantation of hepatitis C-positive livers in hepatitis C-positive patients is equivalent to transplanting hepatitis C-negative livers

A significant number of patients with end-stage liver disease secondary to hepatitis C die of disease-related complications. Liver transplantation offers the only effective alternative. Unfortunately, organ demand exceeds supply. Consequently, some transplant centers have used hepatitis C virus-positive (HCV(+)) donor livers for HCV(+) recipients. This study reviews the clinical outcome of a large series of HCV(+) recipients of HCV(+) liver allografts and compares their course with that of HCV(+) recipients of HCV-negative (HCV(-)) allografts. The United Network for Organ Sharing Scientific Registry was reviewed for the period from April 1, 1994, to June 30, 1997. All HCV(+) transplant recipients were analyzed. Two groups were identified: a group of HCV(+) recipients of HCV(+) donor livers (n = 96), and a group of HCV(+) recipients of HCV(-) donor livers (n = 2,827). A multivariate logistic regression model was used to determine the odds of graft failure and patient mortality, and unadjusted graft and patient survival were determined using the Kaplan-Meier method. There were no differences in demographic criteria between the groups. A greater percentage of patients with hepatocellular carcinoma received an HCV(+) allograft (8.3% v 3.1%; P =.01). Patient survival showed a significant difference for the HCV(+) group compared with the HCV(-) group (90% v 77%; P =.01). Blood type group A, group B, group O incompatibility was significant, with 4.2% incompatibility in the HCV(+) group and only 1.3% in the HCV(-) group (P =.04). Donor hepatitis C status does not impact on graft or patient survival after liver transplantation for HCV(+) recipients. Their survival was equivalent, if not better, compared with the control group. Using HCV(+) donor livers for transplantation in HCV(+) recipients safely and effectively expands the organ donor pool.

Candida fasciitis following renal transplantation

BACKGROUND

We describe a rare case of necrotizing fasciitis involving Candida albicans, an organism that has been reported to have a minimal potential for invasive soft tissue infection. In this case, immunosuppression, chronic renal failure, and a history of diabetes mellitus were predisposing factors.

METHODS

The medical record and histopathologic material were examined. The clinical literature was reviewed for previous cases of C albicans necrotizing fasciitis.

RESULTS

A review of the literature showed that in solid organ transplant recipients, localized fungal soft tissue infection is infrequent, with only 35 cases reported between 1974 and 1992. Necrotizing fasciitis caused by C albicans is extremely rare in the modern era of solid organ transplantation.

CONCLUSIONS

The management of transplant patients at risk for invasive fungal infection warrants a high index of suspicion for fungal necrotizing fasciitis in the setting of wound infection and merits a thorough investigation for atypical pathogens.

Outcome of extra-anatomic vascular reconstruction in orthotopic liver transplantation

BACKGROUND

Portal venous and hepatic arterial reconstruction are critical to successful outcomes in orthotopic liver transplantation (OLT). With portal vein thrombosis or inadequate hepatic arterial inflow, extra-anatomic vascular reconstruction is required. However, the clinical outcomes following extra-anatomic vascular reconstruction are largely unknown.

METHODS

To determine the outcomes associated with extra-anatomic vascular reconstruction, we performed a retrospective review of 205 OLT recipients transplanted between 1995 and 2000.

RESULTS

Extra-anatomic portal venous inflow was based upon the recipient superior mesenteric vein using donor iliac vein graft in a retrogastric position (n = 12). Extra-anatomic arterial inflow was based on recipient infrarenal aorta using donor iliac artery graft through the transverse mesocolon (n = 25). OLT with routine anatomic vascular construction served as control (n = 168). Extra-anatomic vascular reconstruction was not associated with increased morbidity, mortality, operating room time, length of stay, or thrombosis.

CONCLUSION

We conclude that extra-anatomic vascular conduits are associated with excellent long-term outcomes and provide acceptable alternatives for vascular reconstruction in OLT.

Diastereoselective synthesis of substituted tetrahydroquinoline-4-carboxylic esters by a tandem reduction-reductive amination reaction

A diastereoselective synthesis of 1-methyl-2-alkyl- and 2-alkyl-1,2,3,4-tetrahydroquinoline-4-carboxylic esters has been developed from methyl (2-nitrophenyl)acetate (1). The method involves alkylation of 1 with an allylic halide, ozonolysis of the double bond, and catalytic hydrogenation. The final hydrogenation initiates a tandem sequence involving (1) reduction of the aromatic nitro group, (2) condensation of the aniline or hydroxylamine(8) nitrogen with the side chain carbonyl, (3) reduction of the resulting nitrogen intermediate, and (4) reductive amination of the tetrahydroquinoline with formaldehyde produced in the ozonolysis to give a methyl (+/-)-1-methyl-2-alkyl-1,2,3,4-tetrahydroquinoline-4-carboxylate. Removal of the formaldehyde prior to hydrogenation gives the simple (+/-)-2-alkyl derivatives. The products are isolated in high yield as single diastereomers having the C-2 alkyl group cis to the C-4 carboxylic ester. The reaction has been extended to the synthesis of tricyclic structures with similar high diastereoselection.

Hyperacusis in Williams syndrome

OBJECTIVE

To define hyperacusis in audiologic parameters and to further elucidate central and peripheral auditory pathways.

DESIGN AND SETTING

Theories surrounding hyperacusis have always been highly debated. A group of children with Williams syndrome universally complain of hyperacusis. They have highly reproducible behavioural responses to noise and are thus hampered in their social interactions. Loss of inhibitory modulation to efferent sensory input to the cochlea is thought to be a possible mechanism.

METHODS

Nine patients with Williams syndrome received a complete audiologic work-up, including audiogram, speech reception thresholds, acoustic reflexes, impedance, and transient evoked otoacoustic emissions (TEOAEs).

MAIN OUTCOME MEASURES

Assessment of the efferent system is done by measuring changes in TEOAEs following stimulation of the contralateral ear.

RESULTS

Three patients had high-frequency sensorineural hearing loss (SNHL) and thus, as expected, absent TEOAEs, indicating cochlear damage. Two had normal hearing and normal TEOAEs. However, four patients had normal hearing with absent TEOAEs.

CONCLUSIONS

These findings are suggestive of cochlear disease and may, in fact, support the hypothesis of outer hair cell modulation by the ipsilateral medial olivocochlear system. Behavioural aspects of the syndrome make audiologic testing difficult. Thus, the diagnosis of SNHL may be hampered if it truly exists. The data show a preponderance of SNHL in the older age groups of our study population. This either reflects previously missed diagnoses or underlying cochlear disease, which may manifest later in life. Thus, this finding blurs the boundary between loudness recruitment and hyperacusis.

Use of aerosolized inhaled epoprostenol in the treatment of portopulmonary hypertension

BACKGROUND

Portopulmonary hypertension is a known complication in the liver transplant candidate. Intravenous epoprostenol has been demonstrated to decrease pulmonary artery pressures and possibly remodel right ventricle geometry.

METHODS

In this report, we document the efficacy of inhaled aerosolized epoprostenol in a patient with portopulmonary hypertension. The effect was of rapid onset and offset.

RESULTS

After 10 min of delivery, mean pulmonary artery pressure decreased 26%; cardiac output increased by 22%; pulmonary vascular resistance decreased by 42%; and the transpulmonary gradient decreased by 29%. There were no untoward side effects.

CONCLUSION

The inhaled route of delivery of epoprostenol is potential alternative for the acute therapy of portpulmonary hypertension.

The virulence factor AvrXa7 of Xanthomonas oryzae pv. oryzae is a type III secretion pathway-dependent nuclear-localized double-stranded DNA-binding protein

AvrXa7 is a member of the avrBs3 avirulence gene family, which encodes proteins targeted to plant cells by a type III secretion apparatus. AvrXa7, the product of avrXa7, is also a virulence factor in strain PXO86 of Xanthomonas oryzae pv. oryzae. Avirulence and virulence specificities are associated with the central repeat domain, which, in avrXa7, consists of 25.5 direct repeat units. Mutations in three C-terminal nuclear localization signal motifs eliminated avirulence and virulence activities in rice and severely reduced nuclear localization in a yeast assay system. Both pathogenicity functions and nuclear localization were restored on the addition of the sequence for the nuclear localization signal motif from SV40 T-antigen. The loss of avirulence activity because of mutations in the acidic transcriptional activation domain was restored by addition of the activation domain from the herpes simplex viral protein VP16. The activation domain was also required for virulence activity. However, the VP16 domain could not substitute for the endogenous domain in virulence assays. In gel shift assays, AvrXa7 bound double-stranded DNA with a preference for dA/dT rich sequences. The results indicate that products of the avrBs3-related genes are virulence factors targeted to host cell nuclei and have the potential to interact with the host DNA and transcriptional machinery as part of their mode of action. The results also suggest that the host defensive recognition mechanisms are targeted to the virulence factor site of action.

Prospects for understanding avirulence gene function

Avirulence genes are originally defined by their negative impact on the ability of a pathogen to infect their host plant. Many avirulence genes are now known to represent a subset of virulence factors involved in the mediation of the host-pathogen interaction. Characterization of avirulence genes has revealed that they encode an amazing assortment of proteins and belong to several gene families. Although the biochemical functions of the avirulence gene products are unknown, studies are beginning to reveal the features and interesting relationships between the avirulence and virulence activities of the proteins. Identification of critical virulence factors and elucidation of their functions promises to provide insight into plant defense mechanisms, and new and improved strategies for the control of plant disease.

Laparoscopic donor nephrectomy increases the supply of living donor kidneys: a center-specific microeconomic analysis

BACKGROUND

A tenet of microeconomics is that new technology will shift the supply curve to the right. Laparoscopic donor nephrectomy (LDN) is a new technique for removal of living donor kidneys. Centers performing this procedure have noted an increased number of patients presenting for donor evaluation. This has not been previously studied.

METHODS

The records of all LDN performed from May 1998 to February 1999 were reviewed. The following variables were examined: sex, age, related vs. unrelated donation, estimated blood loss, i.v. analgesia, length of stay, and time out of work. Donors undergoing traditional open donor nephrectomy during January 1997 to May 1998 served as the control group. A composite cost index was constructed.

RESULTS

LDN significantly decreased length of stay, pain, and time out of work; the supply function shifted to the right. Telephone interviews revealed that 47% donated solely because of the LDN procedure.

CONCLUSIONS

LDN increases the supply of living donor kidneys.

Laparoscopic donor nephrectomy with a 23-hour stay: a new standard for transplantation surgery

OBJECTIVE

To determine the outcomes associated with laparoscopic donor nephrectomy (LDN) performed as a 23-hour day surgery protocol.

SUMMARY BACKGROUND DATA

Living donor renal transplantation is associated with immediate graft function and prolonged graft survival. The recent application of laparoscopic technology to living renal donation has refocused attention on the advantages of this donor source. LDN is associated with decreased donor pain, length of stay, time out of work, and opportunity costs. The authors hypothesized that LDN would be a viable 23-hour stay procedure.

METHODS

All living donation procedures since May 1998 have been performed with LDN. The 23-hour protocol was initiated in January 1999. LDNs performed from May 1998 to December 1998 and traditional open donor nephrectomy procedures from May 1996 to May 1998 served as historical controls. The following variables were examined: donor sex, related versus nonrelated donation, operative time, blood loss, length of stay, time out of work, recipient and donor serum creatinine levels, hospital charges, and complications.

RESULTS

The 23-hour LDN protocol was associated with high degrees of donor satisfaction. Thirty-six of the 41 donors were discharged within 23 hours; 1 was readmitted. Time out of work was equivalent to that of the control group; graft function was identical among all three comparison groups. Hospital charges were equivalent between the control group and the open nephrectomy group and were significantly decreased in the 23-hour group.

CONCLUSIONS

Laparoscopic donor nephrectomy can be performed as a 23-hour stay procedure without incurring additional complications or donor dissatisfaction. By further decreasing opportunity costs and disincentives for donation, LDN may increase the number of potential donors appearing for evaluation.

Outcome in recipients of dual kidney transplants: an analysis of the dual registry patients

BACKGROUND

A novel but controversial method to increase the utilization of aged donor kidneys is the transplantation of both kidneys as a dual transplant. Initial single-center reports demonstrated outcomes similar to single kidneys from younger donors. In this report, we compare outcome in recipients of kidneys from donors > or =54 years of age who received a single kidney transplant reported to the United Network for Organ Sharing Scientific Registry versus a dual kidney transplant reported to the Dual Kidney Registry.

METHODS

A retrospective analysis was performed, comparing four donor and nine recipient and outcome variables between recipients of a single versus a dual transplant between March 1993 and March 1999.

RESULTS

Dual versus single transplants from donors > or =54 years of age have a significantly decreased incidence of delayed graft function, and lower serum creatinines up to 2 years after transplant despite having kidneys from significantly older donors with poorer HLA matching.

CONCLUSIONS

Dual kidney transplants improve graft performance and outcome in recipients of kidneys from donors > or =54 years of age.

Outcomes of laparoscopic donor nephrectomy in obese patients

The applicability of laparoscopic donor nephrectomy (LDN) has not been assessed in the obese donor. We hypothesized that obesity is not a technical contraindication to LDN. From May 1998 to February 1999, 40 patients underwent LDN at the Georgetown Transplant Institute with the transperitoneal technique. Prophylaxis against deep venous thrombosis consisted of venous compression stockings, low-molecular weight heparin in obese patients, and early ambulation. The following variables were examined: donor sex, age, weight, height, related versus nonrelated donation, body mass index (BMI; wt/ht2), operating room time, estimated blood loss, length of stay, time out of work, and complications. BMI>31 indicates morbid obesity, BMI>27 indicates >20% over ideal body weight, and normal BMI is 25. The patients were divided into nonobese (BMI< or =31) and obese groups (BMI>31). The two groups do not differ in outcome after LDN. Our data indicate that obesity is not associated with increased morbidity or mortality after LDN.

Retroperitoneal compartment syndrome after renal transplantation

We report the case of a 21-year-old man with end-stage renal disease secondary to systemic lupus erythematosus who underwent living related renal transplantation and developed an extraperitoneal compartment syndrome postoperatively.

Transverse hepatectomy for symptomatic polycystic liver disease

Polycystic liver disease can result in massive enlargement of the liver with resultant debilitating symptoms of abdominal pain, chronic fatigue, and severely compromised functional status. Fenestration of hepatic cysts has been advocated as a treatment for polycystic disease. However, in patients with predominant small cyst replacement, fenestration alone often results in limited hepatic volume reduction without improvement in patient functional status. Liver transplantation has also been previously advocated for polycystic liver disease with predominant small cyst replacement, but, with the severe shortage of donor organs, alternative treatment should be considered. In this report we present a case of massive enlargement of the liver with severe clinical debilitation due to polycystic liver disease. Transverse hepatectomy provided a safe and effective alternative to fenestration or liver transplantation.