Comparing phosphorus mobilization strategies using Aspergillus niger for the mineral dissolution of three phosphate rocks.

Phosphorus deficiencies are limiting crop production in agricultural soils worldwide. Locally available sources of raw phosphate rock (PR) are being recognized for their potential role in soil fertility improvement. Phosphorus bioavailability is essential for the efficiency of PRs and can be increased by acid treatments. The utilization of organic acid producing micro-organisms, notably Aspergillus niger, presents a sustainable alternative to the use of strong inorganic acids, but acid production of A. niger strongly depends on the mineral content of the growth media. This study compared the phosphorus mobilization efficiency of two biological treatments, namely addition of acidic cell-free supernatants from A. niger cultivations to PRs and the direct cultivation of A. niger with PRs. The results show that addition of PR to cultivations leads to significant differences in the profile of organic acids produced by A. niger. Additions of PR, especially igneous rocks containing high amounts of iron and manganese, lead to reduced citric acid concentrations. In spite of these differences, phosphorus mobilization was similar between treatments, suggesting that the simpler direct cultivation method was not inferior. In addition to citric acid, it is suggested that oxalic acid contributes to PR solubilization in direct cultivations with A. niger, which would benefit farmers in developing countries where conventional fertilizers are not adequately accessible.

Regional blockade for delivery in women with scoliosis or previous spinal surgery.

We conducted a prospective observational study between 1992 and 2001 identifying obstetric patients with untreated or surgically corrected scoliosis or lumbar-sacral fusion surgery. The regional techniques for labour and delivery that were offered were epidural analgesia, combined spinal epidural anaesthesia (CSE), single shot spinal or continuous spinal anaesthesia (CSA) depending on the degree of scoliosis, previous surgery, cardio-respiratory compromise and planned mode of delivery. Forty women were included in the study, one woman with two separate deliveries, giving 41 cases for analysis. Twenty-four women presented in labour: 11 required no regional technique, seven received effective epidural analgesia and six received CSA. Seventeen women presented for elective caesarean delivery: two received a CSE technique, two received single shot spinal and 13 had CSA. From a total of 19 CSA techniques attempted sixteen catheters were successfully inserted and produced good analgesia or anaesthesia for vaginal or operative delivery in 12 women (63%). There was one case of post dural puncture headache following a CSA for labour and delivery. We discuss the choices available for regional anaesthetic techniques in scoliotic women and the relative merits of each.

JCV-specific cellular immune response correlates with a favorable clinical outcome in HIV-infected individuals with progressive multifocal leukoencephalopathy.

Most immunosuppressed individuals who develop progressive multifocal leukoencephalopathy (PML) have a rapid fatal outcome, whereas some become long-term survivors. We explored the impact of the cellular immune response against JC virus (JCV) on the clinical outcome of 7 HIV+ and 3 HIV- individuals with PML. Of the 4 HIV+/PML survivors, all had detectable cytotoxic T lymphocytes (CTL) specific for JCV T or VP 1 proteins compared to none of the 3 HIV+/PML progressors tested. Of the 3 HIV-/PML patients, 1 was recently diagnosed with PML and showed evidence of neurologic improvement without any treatment. This patient had CTL specific for the VP1 protein of JCV. The other 2 HIV-/PML survivors were stable 3-8 years after the diagnosis of PML. They did not have any detectable CTL against JCV. These findings suggest that JCV-specific immune response is associated with favorable outcome in HIV+ individuals with PML. The lack of detectable JCV-specific CTL in 2 HIV-/PML survivors might indicate a burnt-out disease without sufficient antigenic stimulation to maintain the cellular immune response. The detection of JCV-specific CTL in an HIV- patient recently diagnosed with PML, who was showing evidence of neurological improvement without any treatment, indicates that this finding may be used as a favorable prognostic marker of disease evolution in the clinical management of patients with PML. As the quest for an effective treatment of PML continues, JCV-specific cellular immune response deserves further attention because it appears to play a crucial role in the prevention of disease progression.

The incidence of biopsy-proven glomerulonephritis in Australia.

BACKGROUND: There is limited population-based epidemiological data on renal disease. An insight into the spectrum of clinically significant glomerulonephritis can be obtained from renal biopsy diagnoses. This is a descriptive report of biopsy-proven glomerulonephritis within a defined population. METHODS: A retrospective review of the pathology reports of all native renal biopsies performed in the Australian state of Victoria in 1995 and 1997 was undertaken. Trends in the average annual age- and sex-specific incidence rates for biopsy-proven glomerulonephritis were calculated. Comparisons were made with the incidence of end-stage renal disease due to glomerulonephritis confirmed on renal biopsy. RESULTS: The most common glomerulonephritides in adults are IgA disease, focal glomerulosclerosis, lupus nephritis and vasculitis, and in children are lupus nephritis, focal glomerulosclerosis, IgA disease and minimal change disease. A male predominance is seen for all glomerulonephritides, except lupus nephritis, in both adults and children. An increase in incidence of disease with age, particularly in males, is seen for vasculitis and focal glomerulosclerosis. The most common glomerulonephritides on renal biopsy are reflected in the most common causes of end-stage renal disease due to glomerulonephritis. CONCLUSIONS: This review has provided population-based descriptive epidemiological data on clinically significant glomerulonephritis. This data provides important clues for further studies relating to the identification of risk factors for the various types of glomerulonephritis.

Demonstrating the cost effectiveness of an expert occupational and environmental health nurse: application of AAOHN's success tools. American Association of Occupational Health Nurses.

According to DiBenedetto, "Occupational health nurses enhance and maximize the health, safety, and productivity of the domestic and global work force" (1999b). This project clearly defined the multiple roles and activities provided by an occupational and environmental health nurse and assistant, supported by a part time contract occupational health nurse. A well defined estimate of the personnel costs for each of these roles is helpful both in demonstrating current value and in future strategic planning for this department. The model highlighted both successes and a business cost savings opportunity for integrated disability management. The AAOHN's Success Tools (1998) were invaluable in launching the development of this cost effectiveness model. The three methods were selected from several tools of varying complexities offered. Collecting available data to develop these metrics required internal consultation with finance, human resources, and risk management, as well as communication with external health, safety, and environmental providers in the community. Benchmarks, surveys, and performance indicators can be found readily in the literature and online. The primary motivation for occupational and environmental health nurses to develop cost effectiveness analyses is to demonstrate the value and worth of their programs and services. However, it can be equally important to identify which services are not cost effective so knowledge and skills may be used in ways that continue to provide value to employers (AAOHN, 1996). As evidence based health care challenges the occupational health community to demonstrate business rationale and financial return on investment, occupational and environmental health nurses must meet that challenge if they are to define their preferred future (DiBenedetto, 2000).

Gravity-directed calcium current in germinating spores of Ceratopteris richardii.

Gravity directs the early polar development in single cells of Ceratopteris richardii Brogn. It acts over a limited period of time during which it irreversibly determines the axis of the spore cell's development. A self-referencing calcium selective electrode was utilized to record the net movement of calcium across the cell membrane at different positions around the periphery of the spore during the period in which gravity orients the polarity of the spore. A movement of calcium into the cell along the bottom and out of the cell along the top was detected. This movement was specific, polarized, and strongest in a direction that opposed the vector of gravity. Treatment with nifedipine, a calcium-channel blocker, diminished the calcium current and caused the cell to lose its responsiveness to the orienting influence of gravity. Results shown suggest that calcium plays a crucial role in the ability of a single cell to respond to gravity and in the subsequent establishment of its polarity.

Circadian variation of portal, arterial and venous blood levels of melatonin in pigs and its relationship to food intake and sleep.

Circadian levels of melatonin were determined in the hepatic portal vein, cranial vena cava, and the lower aorta of ten juvenile pigs. Blood was sampled every hour for a total of 24 hr via temporary cannulas introduced into blood vessels under anesthesia. No peak levels of melatonin were found in the mid-scotophase, but hepatic portal concentrations peaked at 06.00 hr. Overall levels of melatonin were highest in the hepatic portal vein (range 35-65 pg/mL), followed by an artery (range 30-55 pg/mL) and the vena cava (range 25-35 pg/mL). Levels of melatonin exhibit strong variation between individual pigs, but generally the average levels from all three sources follow each other's time course. However, on occasion, melatonin levels in the hepatic portal vein varied independently from the levels in the vena cava. Large portal peaks were usually preceded by a feeding period and were associated with a subsequent period of sleep. The data indicate that: 1) there is no clear circadian rhythm of melatonin in the peripheral blood of pigs, 2) relatively little melatonin is metabolized during the first liver passage, 3) food intake may elevate melatonin levels in the hepatic portal vein, and 4) increased levels of melatonin originated in the gastrointestinal tract may induce sleep.

Agreement among three quality of life measures in patients with ALS.

AIM: To determine the concurrent validity of three self-administered health-related quality of life (HRQOL) questionnaires when administered to patients with amyotrophic lateral sclerosis (ALS). BACKGROUND: ALS is the most common motor neuron disease among adults. As a rapidly progressive and fatal disease, ALS has devastating effects on the patient's relationships, functional capacity and mental health. HRQOL measures include information about patients' physical impairments, functional level, and psychosocial status. This study compares a tool designed for the ALS population, the Sickness Impact Profile ALS-19 (SIP/ALS19), and two tools designed to be used in any population, the Quality of Well-being Scale SA (QWB SA), and the SF-36 Health Survey (SF-36). Correlation of the scores would suggest that each tool is valid as a stand-alone measurement of quality of life for this patient population. METHODS: The SIP/ALS-19, the SF-36, and the QWB SA were self-administered to 19 subjects diagnosed with ALS. The scores for each test were ranked and analyzed for agreement using the Spearman rank correlation coefficient. RESULTS: The SIP/ALS-19 demonstrated moderate to good correlation with the QWB SA and fair correlation with the SF-36. The SF-36 had little to no correlation with the QWB SA. CONCLUSIONS: The study did not demonstrate significant correlation among the three quality of life measures. The SIP/ALS-19, SF-36, and QWB SA each have a different focus in measuring HRQOL. The healthcare practitioner should consider the patient's stage of disease, treatment goals, and type of interventions planned when selecting a HRQOL tool for the ALS patient.

Antiangiogenic therapy of a recurrent giant cell tumor of the mandible with interferon alfa-2a.

We report a 5-year-old girl with a large rapidly growing giant cell tumor of the mandible that recurred 2 months after the first surgical excision and 3 months after a second resection. An angiogenic protein, (bFGF), was abnormally elevated in her urine. The patient was treated with interferon alfa-2a for 1 year because this agent inhibits angiogenesis by suppressing bFGF overexpression in infantile hemangiomas and in other human tumors. During this time the bone tumor regressed and disappeared, the urinary bFGF fell to normal levels, and the mandible regenerated. She has remained tumor-free and has been off therapy for 3 years at this writing. This first successful use of interferon alfa-2a to treat a mandibular tumor in a child demonstrates: 1) low grade tumors that overexpress bFGF may respond to interferon alfa-2a, in a manner similar to life-threatening infantile hemangiomas; 2) antiangiogenic therapy, given without interruption for 1 year, was safe and effective in this patient; and 3) treatment may be continued for 1 year without the development of drug resistance.

Management of end-stage renal disease in children.

OBJECTIVE: To review the medical literature on management of end-stage renal disease (ESRD) and its complications in the pediatric patient. DATA SOURCES AND STUDY SELECTION: MEDLINE searches (1970-1997) of the English-language literature. Clinical trials and reviews of drug therapy management were included, and bibliographies were reviewed for relevant articles. DATA SYNTHESIS: Principles of renal replacement therapy in children have been expanded to include maintenance of fluid and electrolyte balance and to manage the complications of ESRD in children. Types of renal replacement and their complications are reviewed. Complications of ESRD are reviewed with emphasis on drug therapy management of anemia of chronic renal failure, growth retardation, and hypertension. A discussion of the use of vitamins and supplements to maintain bone and mineral homeostasis is provided, and specific recommendations for vaccination of children with ESRD are given. CONCLUSIONS: Children with end-stage renal failure present a unique challenge to the pharmacist. Renal replacement therapy for children with ESRD involves some form of dialysis and an intensive medication regimen. Complications must be treated with appropriate drug therapy. Drug therapy must be monitored closely for dosage adjustment, clinical response, drug interactions, and toxicity. Patients and families must receive continuous education and follow-up to encourage compliance. The pharmacist must work closely with the healthcare team to optimize drug therapy and improve patient education and compliance.

Determining whether managed care formularies meet the needs of pediatric patients.

UNLABELLED: This activity is designed for healthcare providers making formulary decisions for managed care organizations. GOAL: To help clinicians determine whether managed care formularies meet the needs of pediatric patients. OBJECTIVES: 1. List general considerations for establishing a pediatric drug formulary. 2. Understand the importance of growth and development when selecting drug therapy for pediatric patients. 3. Discuss potential difficulties with administering medications during school hours. 4. Identify specific medications within the drug classes of antibiotics, asthma medications, endocrine, and gastrointestinal agents that should be available on a pediatric drug formulary.

Melatonin concentrations in serum and tissues of porcine gastrointestinal tract and their relationship to the intake and passage of food.

Melatonin concentrations were determined in serum and 10 segments of the gastrointestinal tract (GIT) of 48 pigs (100 kg weight). The animals were fasted for 30 hr and then sacrificed 0, 1, 2, 5, 10, and 20 hr after refeeding. Peak amount of gastric digesta (2,428 g) and ileum digesta (850 g) were observed 1 hr and 5 hr, after refeeding, respectively. Conversely, colon content reached a minimal weight (726 g) at 2 hr after refeeding. Serum levels of melatonin increased from 3.4 pg/ml to 15.5 pg/ml (peak 5 hr after refeeding). Melatonin levels in GIT tissues before refeeding varied from 23.8 pg/g (stomach-fundus) to 62.1 pg/g (rectum). Increasingly higher levels of melatonin were detected in the distal segments of the GIT. Higher melatonin levels after refeeding were observed in most GIT tissues except the rectum. In most tissues, peak melatonin values were detected 5 hr after refeeding. A significant change in weight of digesta across time (P < 0.05) was detected in the stomach, ileum, and cecum. Similar changes in melatonin levels across time were found in most tissues except the esophagus, stomach (cardia and pylorus), and rectum. Adjacent GIT tissues exhibited similar (P < 0.05) melatonin levels. The GIT melatonin levels correlated best with the variation of digesta weight in the ileum. In addition, the increase of serum melatonin levels correlated best with the increase of GIT melatonin levels in the distal part of the GIT. Our results suggest that melatonin produced in the ileum, cecum, and colon may contribute significantly to the short-term increase of serum melatonin levels observed after refeeding.

Episodic versus prophylactic infusions for hemophilia A: a cost-effectiveness analysis.

OBJECTIVE: To assess the incremental cost-effectiveness of prophylactic compared with episodic care in boys with severe hemophilia A. SETTING: Eleven U.S. hemophilia treatment centers. METHODS: Charge data from a randomly selected cohort of 70 boys receiving episodic infusions for bleeding events and from all 27 boys receiving infusions prophylactically were collected from documents obtained from the hemophilia treatment centers during a period of approximately 2 years. Published and public sources were used for conversion to cost, lifetime earnings, and earnings losses from disability. A model was constructed for a hypothetical patient from ages 3 to 50 years by means of three infusion scenarios. RESULTS: The cohort receiving prophylactic treatment had fewer bleeding events each year (median, 3 vs 31) but used more concentrate (3323 vs 1015 units/kg per year). Factor VIII concentrate accounted for more than 93% of the cost of both episodic and prophylactic care. Compared with episodic infusion, prophylaxis from ages 3 to 20 years costs $1100 per bleeding event prevented, in comparison with $1380 for prophylaxis from ages 3 to 50 years. The total cost of prophylactic care from ages 3 to 50 years would equal the current total cost of episodic care if the price of the concentrate were decreased by 50%. CONCLUSION: Prophylactic care markedly reduces the number of bleeding events and should prevent joint function impairment, but at substantial cost.