Evidence for widespread changes in the structure, composition, and fire regimes of western North American forests.

Implementation of wildfire- and climate-adaptation strategies in seasonally dry forests of western North America is impeded by numerous constraints and uncertainties. After more than a century of resource and land use change, some question the need for proactive management, particularly given novel social, ecological, and climatic conditions. To address this question, we first provide a framework for assessing changes in landscape conditions and fire regimes. Using this framework, we then evaluate evidence of change in contemporary conditions relative to those maintained by active fire regimes, i.e., those uninterrupted by a century or more of human-induced fire exclusion. The cumulative results of more than a century of research document a persistent and substantial fire deficit and widespread alterations to ecological structures and functions. These changes are not necessarily apparent at all spatial scales or in all dimensions of fire regimes and forest and nonforest conditions. Nonetheless, loss of the once abundant influence of low- and moderate-severity fires suggests that even the least fire-prone ecosystems may be affected by alteration of the surrounding landscape and, consequently, ecosystem functions. Vegetation spatial patterns in fire-excluded forested landscapes no longer reflect the heterogeneity maintained by interacting fires of active fire regimes. Live and dead vegetation (surface and canopy fuels) is generally more abundant and continuous than before European colonization. As a result, current conditions are more vulnerable to the direct and indirect effects of seasonal and episodic increases in drought and fire, especially under a rapidly warming climate. Long-term fire exclusion and contemporaneous social-ecological influences continue to extensively modify seasonally dry forested landscapes. Management that realigns or adapts fire-excluded conditions to seasonal and episodic increases in drought and fire can moderate ecosystem transitions as forests and human communities adapt to changing climatic and disturbance regimes. As adaptation strategies are developed, evaluated, and implemented, objective scientific evaluation of ongoing research and monitoring can aid differentiation of warranted and unwarranted uncertainties.

Predicting forest floor and woody fuel consumption from prescribed burns in southern and western pine ecosystems of the United States.

We present pre-burn biomass and consumption data from 60 prescribed burns in the southeastern and western United States. The datasets include pre-burn biomass in Mg/ha by fuel category: herbaceous fuels, shrubs, 1-hr, 10-hr, 100-hr, 1000-hr, 10,000-hr, and > 10,000-hr downed wood, litter and duff. Pre-burn depth (cm) and reduction (cm) are provided for litter and duff layers. Day-of-burn fuel moistures and weather are also listed by site.

Hyperapobetalipoproteinemia: the major dyslipoproteinemia in patients with chronic renal failure treated with chronic ambulatory peritoneal dialysis.

In the present study, plasma cholesterol, triglyceride, low density lipoprotein (LDL)-cholesterol, high density lipoprotein (HDL)-cholesterol, and the major protein in LDL, apoB, were measured in 28 patients with chronic renal failure treated with hemodialysis and in 28 patients with chronic renal failure treated with chronic ambulatory peritoneal dialysis (CAPD). Elevated plasma triglycerides and reduced HDL cholesterol were frequent in both the hemodialysis and CAPD patients. However LDL levels were significantly higher in the CAPD patients as evident both by LDL cholesterol and LDL apoB. Even so, only one of the CAPD patients was hypercholesterolemic whereas 14 (or 50%) had hyperapobetalipoproteinemia (HyperapoB). Insulin-dependent diabetes was more frequent in the CAPD group but only 2 of the 9 insulin-dependent diabetics in this group had HyperapoB, and therefore, diabetes mellitus cannot account for the difference between the 2 groups. Thus HyperapoB appears to be a prevalent dyslipoproteinemia in CAPD patients and as such might be another factor which places CAPD patients at particularly increased risk of atherosclerosis.

The Kidney Disease Questionnaire: a test for measuring patient knowledge about end-stage renal disease.

Two studies report on the development of the Kidney Disease Questionnaire (KDQ) as a test for measuring patient knowledge about end-stage renal disease and its treatment. The KDQ is available in a 26-item version or as two parallel 13-item tests. Psychometric evaluations indicate that all versions show high levels of reliability. Initial validity tests are also promising. The KDQ is able to discriminate individuals well informed about kidney disease and its treatment from those who are not so well informed. It is also sensitive to the effects of an experimental education program and to ESRD-related knowledge that is acquired as a result of starting dialysis. Data and issues related to the administration, readability, demographic correlates, and a French translation of the KDQ are also presented and discussed.

A prospective study on the impact of the renal biopsy in clinical management.

A three year prospective study involving 80 patients was conducted to assess the impact of renal biopsy on clinical management. Pre-biopsy predicted histologic diagnosis was changed in 35 (44%) of the patients as a result of the biopsy. Prognosis changed in 45 (57%) of the patients. Therapy changed in 25 (31%) of the patients. These results suggest that, overall, renal biopsy had a marked effect on management. However, we identified subgroups of patients who were unlikely to have their management changed as a result of the biopsy: of 16 patients with a pre-biopsy diagnosis of IgA nephropathy, 1 (6%) had treatment changed because of the biopsy; and of the 50 patients without heavy proteinuria (greater than 3 g/24 h), 10 (20%) had treatment changed because of the biopsy. Although our overall results suggest an important role for renal biopsy in clinical management, renal biopsy has the least apparent impact in patients with a pre-biopsy diagnosis of IgA nephropathy or without heavy proteinuria.

Major and minor risk factors for cardiovascular disease in peritoneal dialysis.

All uremic patients have multiple risk factors for CAD including in many, the conditions that caused their ESRD--for example, diabetes and hypertension. conventional risk factors--for example, dyslipidemia and hyperhomocysteinemia. risk factors that are unique to uremia--for example, calcium and phosphate abnormalities. PD patients have particular risk with respect to their lipid status and hyperinsulinemia. Many of these risks are potentially modifiable, but evidence does not exist to assess the impact of treatment on clinical outcomes. Therefore, current decisions for therapy directed at risk factor modification must be made on an individual basis.

Major and minor risk factors for cardiovascular disease in continuous ambulatory peritoneal dialysis patients.

Uremia in general and peritoneal dialysis in particular bring with them risk factors for the development of cardiovascular disease. These factors include multiple lipid abnormalities, hyperhomocysteinemia, abdominal obesity, chronic inflammation, hypoalbuminemia, oxidative stress, and AGE formation. When these are combined with conventional risk factors, one can appreciate why the incidence of cardiovascular disease is so high in peritoneal dialysis patients. Treatment strategies should address each of these risks appropriately.

Socioeconomic and health-care policies and peritoneal dialysis.

1. All ESRD treatments is expensive and a modality change adds considerably to that expense. 2. Ideally, the cost of ESRD therapy should be reported as the cost incurred for all aspects of the treatment to the health-care system. 3. Most studies show peritoneal dialysis to be less expensive than hemodialysis, but this can vary depending on the local costs of supplies and labor. 4. Strategic decisions with regard to new innovations should be made after a full analysis of all of the involved costs and savings that the innovation might introduce. 5. Economic factors and reimbursement rates appear to have an important impact on modality selection.

Treatment modality selection in 150 consecutive patients starting ESRD therapy.

OBJECTIVE: The purpose of this study was to assess the reasons for treatment modality selection between hemodialysis (HD) and peritoneal dialysis (PD) in 150 consecutive patients in a single center. DESIGN: This study is a retrospective study using chart review as the data collection method. SETTING: A single tertiary care university teaching hospital. PATIENTS: One hundred and fifty consecutive patients starting end-stage renal disease (ESRD) therapy at the Royal Victoria Hospital in Montreal were assessed. Their treatment modality at 6 weeks after starting dialysis was recorded as their treatment modality. Patients transplanted or who died prior to that 6-week period were excluded. MAIN OUTCOME MEASURES: The treatment modality, that is, either HD or PD, at 6 weeks after the initiation of ESRD was the modality assigned to the patient. RESULTS: One hundred and fifty patients started ESRD therapy of whom 83 went to HD and 67 to PD. Thirty-one patients were directed to HD, including 20 for social reasons, 3 with ostomies, and 6 with unsuitable abdomens. Fourteen patients were directed to PD, including 10 with severe cardiovascular disease, 3 with no vascular access, and one for geographical reasons. Of 31 diabetics who were encouraged to do PD, 17 went to PD and 14 to HD (10 for social reasons, 3 refused PD, and one with an inappropriate abdomen). Seventy-four patients were initially eligible for either PD or HD. Fifty percent (37) went to PD and 50% to HD. Of those going to HD, 15 went to self-care HD, of whom 7 had prior exposure to HD. Eleven were not informed regarding PD. There was no gender preference for PD versus HD. CONCLUSION: We conclude that among informed patients, if given a choice of treatment modality, the majority will choose self-care dialysis including continuous ambulatory peritoneal dialysis (CAPD) or self-care HD.

Cardiovascular disease in peritoneal dialysis.

Cardiovascular morbidity and mortality remain high in ESRD patients. Lipid abnormalities in CAPD may be more important than in hemodialysis. Vessel calcification may have a role in atherosclerotic heart disease, but this is only an inference from several clinical observations, and it remains to be defined more clearly as a risk factor. Left ventricular hypertrophy is frequent in this patient population, and is associated with specific clinical patterns and an increased risk of death. Erythropoietin treatment of anemia and tight blood pressure controls have proved to help in reversing severe left ventricular hypertrophy. Finally, we describe a syndrome of the hypertrophic, high cardiac output hemodialysis heart, which is characterized by a high cardiac output in hemodialysis patients. It is associated with left ventricular hypertrophy and eventually right ventricular hypertrophy with tricuspid insufficiency. This may require fistula revision and even a switch peritoneal dialysis.

Successful pregnancy complicated by peritonitis in a 35- year old CAPD patient.

A 35-year old woman conceived six months after initiating continuous ambulatory peritoneal dialysis (CAPD). A medical plan was developed to give the patient adequate dialysis for a 1.5 g/kg/day protein intake. In addition, alterations in calcium, magnesium, and erythropoietin administration were required to reach the objectives set by the obstetrical/renal team. Three weeks prior to delivery, an amniotic leak developed, and vaginal cultures were positive for Escherichia coli. Oral amoxicillin was administered (500 mg per os q.i.d.) until the day of delivery. A 1545-g baby girl was delivered by cesarean section at 32 weeks. Five days postpartum the patient developed severe peritonitis, which subsequently grew E. coli. The patient fully recovered from the peritonitis, but catheter removal was required. Successful pregnancy can be expected on CAPD, and adequacy can be achieved with aggressive dialysis. Cesarean section delivery should probably be accompanied by full peritonitis therapy.

Patients on chronic peritoneal dialysis for ten years or more in North America.

Thirty-six patients on peritoneal dialysis (PD) for more than ten years in six North American centers were analyzed retrospectively. In the six centers, the percentage of patients surviving for more than ten years varied between 0.8% and 7.3%. The study group included 27 females and 9 males aged 38.6 +/- 14.2 years [mean +/- standard deviation (SD)] at the start of treatment. Of the 36 patients, 28 were Caucasian. The most common cause of end-stage renal disease (ESRD), present in 12 patients, was chronic glomerulonephritis. Only 4 patients had diabetes. At the beginning of the study, 19 patients had hypertension (the most common comorbid condition); 11 had no comorbid conditions at the start. Creatinine clearance at the start was 4.12 +/- 3.5 mL per minute, and the mean duration to anuria was 51 +/- 25 months. Mean initial body weight was 55 +/- 9 kg, and mean body surface area was 1.5 +/- 0.2 m2. Serum albumin levels showed an increase from 33.8 +/- 3.6 g/L at the start of the study to 38.2 +/- 3.9 g/L at the end. Hospitalization rate was low at 0.5 +/- 0.3 admissions per patient-year, and duration of hospitalization was 4.8 +/- 3.7 days per patient-year. Peritonitis was the most common cause of hospitalization. The mean peritonitis rate was 1 episode every 52 +/- 48 patient-months. There were 36 catheter changes in 18 patients; 16 patients had a single PD catheter throughout the period of study. Autonomous hyperparathyroidism was the most common long-term complication. At the end of the study period, 11 patients were still on PD, 9 had died, 5 had been transferred to hemodialysis (HD), 1 was alive with a functioning allograft, and 1 was lost to follow-up. We conclude that patients who survive longer than ten years on PD are most likely to be young Caucasian females, small in body size, who are non diabetic, with few comorbid conditions. These long-term survivors have few hospitalizations, and their peritonitis rate is low. In this group of patients, severe autonomous hyperparathyroidism is the most common long-term complication.

Combined hemofiltration and desferrioxamine treatment for aluminum induced osteomalacia.

A 61-year-old male hemodialysis patient developed the syndrome of aluminum intoxication including bone pain, fractures, proximal myopathy, progressive anemia and expressive aphasia. Serum aluminum was 130 micrograms/l and rose to 445 micrograms/l after the administration of 2 grams of desferrioxamine. Bone biopsy of the iliac crest revealed severe osteomalacia, heavy staining for aluminum and a bone aluminum content of 229 mg/kg dry bone. Treatment with combined hemofiltration and desferrioxamine administration led to a marked clinical improvement and a repeat bone biopsy striking healing of the osteomalacia with a bone aluminum content of 11 mg/kg dry bone.

ESRD treatment modality selection: which factors are important in the decision?

UNLABELLED: The purpose of this study was to determine which factors are most important in choosing between ESRD treatments and to assess if patients, R.N.'s and M.D.'s agree or differ as to the level of importance of different factors. METHODS: 22 patients, 11 R.N.'s and 10 M.D.'s were interviewed to determine which factors should be considered. Forty-three factors were identified relevant to CAPD and hemodialysis. Then 14 patients, 8 R.N.'s and M.D.'s were asked to rate each of these factors on a scale of 1-10 (10 being most important) and the average score for each was computed. The factors were then ranked in order of importance (1 being most important). The results revealed that peritonitis ranked as overall the most important factor in determining treatment modality choice. In general, life style considerations ranked higher than medical consequences of a specific therapy. There was concordance amongst the three groups in some areas but there were also differences between patients, R.N.'s and M.D.'s. This raises important issues with regards to the adequacy of patient counselling.

Protection of cattle against heartwater in Botswana: comparative efficacy of different methods against natural and blood-derived challenges.

Five groups of Tswana-cross castrated male cattle between 20 and 30 months of age (a total of 158 animals) were transported from a ranch in a heartwater-free area of south Botswana to a feedlot near Gaborone in the east of Botswana where heartwater is endemic. On arrival, one group was vaccinated intravenously with the Onderstepoort sheep blood heartwater vaccine, one group was vaccinated intravenously with the new Onderstepoort tick-derived heartwater vaccine and a third group was vaccinated subcutaneously with this tick-derived vaccine. Vaccine reactions were blocked with long acting oxytetracycline on the first day of fever. A fourth group had a series of injections of long acting oxytetracycline on days 0, 7, 14 and 21 after arrival, and a fifth served as untreated controls. The animals remained at the feedlot for 65 days during which time they faced a low level of challenge by Amblyomma hebraeum ticks. None contracted heartwater and so they were then challenged, together with a further group of control cattle, with a dose of the sheep blood vaccine. Some animals in all groups had severe heartwater reactions and died despite therapy, but 76.7 per cent, 64.5 per cent and 74.3 per cent of the cattle in the blood vaccine, intravenous tick vaccine and long acting oxytetracycline groups respectively were resistant to challenge, compared with 48.3 per cent of the subcutaneous tick vaccine group and 36.4 per cent of the controls. It was concluded that intravenous vaccination of susceptible adult cattle with either the blood or the tick-derived vaccine needs careful monitoring in the month after vaccination and does not necessarily result in immune animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Decision process about options in renal therapy substitution: selection versus election.

No renal replacement therapy stands alone. Hemodialysis, peritoneal dialysis and transplantation each have a role to play in the care of our patients. When one fails, another can replace that modality. Patients and staff should be counselled accordingly. The responsibility of healthcare workers is to try to best match the medical condition and lifestyle of the patients with the renal replacement therapy available. Furthermore the patients should have sufficient information to be able to make these decisions wisely.

Factor structure of the College Adjustment Scales.

The present study examined the underlying structure of the College Adjustment Scales via principal components analysis. A correlation matrix of the nine subscales showed significant multicolinearity. A subsequent principal components analysis demonstrated that one factor accounted for 57% of the total variance and that the majority of subscales were moderately correlated with this single factor. The results suggest that the College Adjustment Scales may measure the same underlying construct and that the clinical distinctions implied by subscale scores should be regarded with caution. Conclusions are constrained by sample size and demographic characteristics, but the results suggest the need for further empirical validation of the College Adjustment Scales, which may be useful in college counseling centers.