Incidence of end-stage renal disease in medically treated patients with severe bilateral atherosclerotic renovascular disease

Incidence of end-stage renal disease in medically treated patients with severe bilateral atherosclerotic renovascular disease. Atherosclerotic renovascular disease is an important cause of end-stage renal disease (ESRD). The exact incidence of ESRD and the rate of decline in glomerular filtration rate (GFR) in patients with this condition is unknown. We report the mortality, the rate of decline in renal function, and incidence of ESRD in 51 patients with bilateral atherosclerotic renovascular disease followed-up for a median period of 52 months. None of these patients had undergone any surgical or radiological intervention. Renal function was determined by serial measurements of serum creatinine. Bilateral atherosclerotic renovascular disease was associated with a high mortality rate; the crude mortality rate at 60 months was 45%. Assessment of renal function showed impaired renal function at time of angiography and a nonuniform and variable decline in renal function during the period of observation. The median GFR decreased from 39 mL/min (range, 15 to 80 mL/min) at time of angiography to 31 mL/min (range, 10 to 70 mL/min) and 24 mL/min (range, 10 to 40 mL/min) at 24 and 60 months, respectively (P < 0.05). The calculated mean rate of decline in GFR for all patients was 4 mL/min/yr (range, 1 to 16 mL/min/yr). Over the 5 years, there was a progressive increase in the incidence of ESRD. Of the original 51 patients who underwent angiography, six patients reached ESRD. The crude incidence of ESRD was, therefore, 12%. Patients who reached ESRD were characterized by advanced azotemia at the time of angiography (median GFR, 25 mL/min) and a rapid decline in GFR (8 mL/min) compared with patients who did not reach ESRD during the observation period (median GFR, 43 mL/min and an average rate of decline GFR of 3 mL/min).

Previous breast biopsy for benign disease rarely complicates or alters interpretation on screening mammography

OBJECTIVE

It has been suggested that breast screening leads to too many biopsies for benign disease that permanently scar the breast and confuse the interpretation of subsequent mammograms. We undertook retrospective and prospective studies to determine how often an excisional biopsy for benign breast disease complicates or alters interpretation of screening mammograms.

MATERIALS AND METHODS

Retrospective review of our screening center database yielded 31,025 asymptomatic patients who had routine mammographic screening studies between 1993 and 1996. Of the 58,538 examinations of these patients, 53,510 were of patients who had no history of breast biopsy and 5028 were of patients who had a history of breast biopsy for benign disease. Recall rates were compared between the two groups. In the prospective study, radiologists reviewed the mammograms of 1997 consecutive patients presenting to the screening center, 173 of whom reported a prior breast biopsy for benign disease. The radiologist interpreting the images determined how often evidence of the biopsy site was apparent on the mammogram and how often such changes necessitated additional imaging.

RESULTS

In the retrospective study, 3296 (6%) of the 53,510 studies done in patients who did not have a biopsy for benign disease and 360 (7%) of the 5028 studies done in women who had a biopsy for benign disease led to additional imaging. Eight recalls for further imaging (0.16%) among the 5028 studies in women with a prior biopsy for benign disease were related to the biopsy site. In the prospective study, 24 (14%) of the 173 women who had a biopsy for benign disease had mammographic evidence of the biopsy site. Nine (5%) of the 173 women who had previously had a biopsy for benign disease and 86 (5%) of the 1824 patients without a prior biopsy were recalled for additional imaging. No women were recalled because a previous breast biopsy for benign disease led to confusion or diagnostic concern.

CONCLUSION

Changes in patients' breasts due to previous excisional biopsies for benign breast disease rarely pose a diagnostic dilemma in the interpretation of routine screening mammograms.

Long-acting inhaled beta2-agonists in asthma therapy

OBJECTIVE

To review the pharmacology of the long-acting inhaled beta2-agonists, salmeterol and formoterol, summarize results of their clinical trials, evaluate their safety records, and discuss their roles in the treatment of asthma.

DATA SOURCES

Preclinical and clinical studies involving salmeterol or formoterol were identified by a MEDLINE search, weekly computerized literature updates, and manual searches. Studies of satisfactory quality were chosen for review.

DATA SYNTHESIS

Salmeterol and formoterol are potent and selective beta2-adrenoceptor agonists with durations of action >12 h. Their major differences are that formoterol has a rapid onset of action and is a partial agonist of high intrinsic efficacy, whereas salmeterol has a delayed onset and is a partial agonist of low intrinsic efficacy. Twice daily use of either drug results in improved lung function, reduced symptoms, and a better quality of life. These agents protect against exercise-induced asthma for 12 h and eliminate nighttime awakening in most patients. Limited tolerance develops, especially to their bronchoprotective effects, but their improvement of lung function is sustained.

CONCLUSIONS

Regular use of salmeterol or formoterol provides subjective and objective amelioration of asthma in patients experiencing excessive symptoms or physiologic impairment despite the regular administration of low doses of inhaled corticosteroids (equivalent to approximately 500 microg/d of beclomethasone). Intermittent use of either long-acting beta2-agonist can provide prolonged protection against exercise-induced asthma or nighttime symptoms. Patients should be instructed to continue taking inhaled steroids when long-acting beta2-agonists are administered on a regular schedule and to not take long-acting beta2-agonists between regularly scheduled doses. Used properly, they are effective and safe adjunctive agents in the treatment of asthma.

Salmeterol-induced desensitization, internalization and phosphorylation of the human beta2-adrenoceptor

1. Partial agonists of the beta2-adrenoceptor which activate adenylyl cyclase are widely used as bronchodilators for the relief of bronchoconstriction accompanying many disease conditions, including bronchial asthma. The bronchodilator salmeterol has both a prolonged duration of action in bronchial tissue and the ability to reassert this activity following the temporary blockade of human beta2-adrenoceptors with antagonist. 2. We have compared the activation and desensitization of human beta2-adrenoceptor stimulation of adenylyl cyclase induced by salmeterol, adrenaline and salbutamol in a human lung epithelial line, BEAS-2B, expressing beta2-adrenoceptor levels of 40-70 fmol mg(-1), and in human embryonic kidney (HEK) 293 cell lines expressing 2-10 pmol mg(-1). The efficacy observed for the stimulation of adenylyl cyclase by salmeterol was only approximately 10% of that observed for adrenaline in BEAS-2B cells expressing low levels of beta2-adrenoceptor, but similar to adrenaline in HEK 293 cells expressing very high levels of receptors. Salmeterol pretreatment of these cells induced a rapid and stable activation of adenylyl cyclase activity which resisted extensive washing and beta2-adrenoceptor antagonist blockade, consistent with binding to a receptor exosite and/or to partitioning into membrane lipid. 3. The desensitization and internalization of beta2-adrenoceptors induced by the partial agonists salmeterol and salbutamol were considerably reduced relative to the action of adrenaline. Consistent with these observations, the initial rate of phosphorylation of the receptor induced by salmeterol and salbutamol was much reduced in comparison to adrenaline. 4. Our data suggest that the reduction in the rapid phase of desensitization of beta2-adrenoceptors after treatment with salmeterol or salbutamol is caused by a decrease in the rate of beta2-adrenoceptor kinase (betaARK) phosphorylation and internalization. In contrast, the rate of cyclic AMP-dependent protein kinase (PKA)-mediated phosphorylation by these partial agonists appears to be similar to adrenaline.

Screening mammography: effect of national guidelines on current physician practice

PURPOSE

To evaluate the effect of national breast cancer screening guidelines on current physician attitudes toward and practice of screening mammography.

MATERIALS AND METHODS

Questionnaire responses from 278 physicians were analyzed. The questionnaire had four sections: general information on physician practice and experience, current use of breast cancer screening, perceptions of screening mammography, and physician awareness of and response to the controversy in breast cancer screening.

RESULTS

In women aged 40-49 years, 144 (52%) of 278 physicians performed annual clinical breast examination and screening mammography every 2 years; 57 (21%) favored annual mammography and clinical breast examination. In women aged 50 years and older, 232 (83%) physicians screened patients annually with clinical breast examination and mammography. Two hundred seventeen (78%) physicians were aware of the recommended changes in screening guidelines; 54 (19%) were not aware of the changes. Of those aware of the changes, 56 (26%) changed to the new guidelines, 150 (69%) did not change, and six (3%) modified their practice somewhat.

CONCLUSION

Physician practice as regards screening mammography is influenced by national guidelines.

Should women with implants or a history of treatment for breast cancer be excluded from mammography screening programs?

OBJECTIVE

Our objective was to determine whether it is scientifically justified to require that women with implants or a history of treatment for breast cancer be screened in a diagnostic mammography setting and that they be excluded from mammography screening programs.

MATERIALS AND METHODS

The recall rates for women with breast implants or a history of treatment for breast cancer who were screened in a dedicated mammography screening program were compared with those of other women in the screening program. The computerized records for the breast screening program of the Department of Radiology at our institution for January 1, 1990, through December 31, 1995, were reviewed. The recall rates for women who had breast implants and those for women with a history of treatment for breast cancer were compared with the recall rates for the other women who underwent screening. Each recall rate included women who were called back for additional evaluation in addition to those for whom a biopsy was recommended on the basis of the screening study.

RESULTS

Of 45,134 screening examinations done during the review period, 43,454 (96%) were for women who had no history of breast cancer or of breast implants; 590 (1%) were for women who had undergone mastectomy; 991 (2%) were for women who had been treated with lumpectomy and irradiation for breast cancer; and 99 (0.2%) were for women with breast implants. Among the 43,454 examinations of women with no history of breast cancer or implants, 3081 examinations (7%) led to interpretations that produced requests for the patient to return for additional evaluation. Thirty-six women who had been treated for breast cancer by mastectomy were recalled (6%). Seventy-five women who had undergone lumpectomy and irradiation for breast cancer were recalled (8%). Five women with breast implants were recalled (5%). Statistically, these rates were not significantly different.

CONCLUSION

We find no scientific reason to exclude women who have been treated for breast cancer or who have breast implants from dedicated screening programs.

Reduced dose OKT3 prophylaxis in sensitised kidney recipients

Prophylactic use of the monoclonal antibody OKT3 has been studied for the prevention of rejection in sensitised renal transplant recipients. Patients receiving a full dose (FD) regimen were compared to a subsequent consecutive group of patients receiving a reduced dose (RD) regimen. The characteristics of the two groups were not significantly different with regard to age, HLA mismatch and panel-reactive antibody (PRA) status. The number of days that OKT3 was given was 12.9 +/- 1.8 for the FD regimen and 11.3 +/- 2.8 for the RD regimen. The total dose of OKT3 given was 64.4 +/- 9 mg (FD) and 38.3 +/- 8.5 mg (RD). Patient survival at 12 months was 8/8 for FD and 17/17 for RD. Graft survival at 12 months was 7/8 for FD and 17/17 for RD. Creatinine at 24 months was 185 +/- 68 and 201 +/- 81 mumol/l for FD and RD, respectively. A reduced dose regimen of OKT3 produced excellent and comparable results to the standard recommended full-dose regimen. The cost per patient was reduced 40% from 5676 pounds for FD to 3344 pounds for RD.

Foolers: things that look like pneumonia in children

Pulmonary infiltrates on chest radiographs are common findings in the pediatric age group and are generally associated with acute infectious pneumonias. Occasionally, however, these "pneumonias" fail to respond to appropriate antibiotic therapy. Under these circumstances, noninfectious conditions that may be associated with pulmonary infiltrates should be considered. Thus, it is important that physicians who care for children have some knowledge of these potential "mimickers" of childhood pneumonia.

Repetitive endocytosis and recycling of the beta 2-adrenergic receptor during agonist-induced steady state redistribution

The human beta 2-adrenergic receptor (beta 2AR) rapidly internalizes after binding agonist, resulting in a dramatic redistribution of receptors from the plasma membrane and into endocytic vesicles. We sought to determine whether intracellular receptors constitute a static pool or represent a fraction of dynamically internalizing and recycling receptors. Using cells expressing a beta 2AR with an epitope tag at its amino-terminal ectodomain, changes in surface receptor levels were measured by flow cytometry and radioligand binding assays. The addition of a saturating level of a strong agonist (isoproterenol) caused the endocytosis of receptors with first-order kinetics (ke for naive cells, 0.222 min-1). After 10 min, the level of surface receptors remained stable at approximately 20% that of untreated cells, even though endocytosis continued with similar kinetics (ke for pretreated cells, 0.258 min-1), suggesting that internalized receptors were cycling in steady state with surface receptors. This prediction was confirmed directly by showing that internalized beta 2ARs recycled to the cell surface in the continued presence of agonist. The calculated transit times (1/k) in the presence of isoproterenol were 3.9 min for endocytosis and 11.2 min for recycling. The endocytic rate constant and the steady state redistribution to the internal pool were much lower after treatment with the partial agonist albuterol, suggesting a correlation between the efficiency of endocytosis and that of receptor coupling to the downstream signal transduction pathway. These findings indicate that in the presence of agonist, beta 2ARs are in a dynamic steady state between the plasma membrane and endosomes that is regulated principally by agonist efficacy.

Positive predictive value of breast biopsy performed as a result of mammography: there is no abrupt change at age 50 years

PURPOSE

To determine if the positive predictive value (PPV) of a biopsy initiated because of an abnormal mammogram changes abruptly at age 50 years.

MATERIALS AND METHODS

The PPV and its variation with age was analyzed for 4,778 women who underwent biopsy for a clinically occult abnormality detected at mammography. The relationship of the results to the patient's age was analyzed with age represented as a continuous and two-categorized (< 50, > 50) measure. The latter measure represented an abrupt change, which distinguished those aged 49 years and younger from those aged 50 years and over. With this measure, the patients in each of the two age groups were statistically indistinguishable.

RESULTS

The results were consistent with a steady increase in PPV and the yield of cancers with age, and there was no abrupt change at age 50 years. The modeled PPV for all cancers for these 4,778 patients was approximately 12% for women aged 40 years and increased to 46% by age 79 years.

CONCLUSION

The PPV did not change abruptly at any age for women aged 40-79 years but increased steadily, which reflects the prior probability of breast cancer at each age. Inappropriate grouping of data can lead to misinterpretation of results. Screening guidelines should not be predicated on the false assumption that this variable changes at age 50 years.

Physicians' opinions on the delivery of mammographic screening services: immediate interpretation versus double reading

OBJECTIVE

Mammographic services are delivered in many ways. Emphasis has been placed on providing women with immediate reports of their screening mammograms. We believe that double reading of mammograms is more important than an immediate report. We sought to determine physicians' attitudes toward this issue and if education affects their opinions.

MATERIALS AND METHODS

Questionnaires were mailed to 1000 physicians in Massachusetts who were randomly selected from 16,000 members of the state medical society. The questionnaire had four sections, of which two were pertinent to this subject. The first section collected general information on the physician's practice and experience. The second section described two common delivery systems for mammographic screening services and asked physicians to choose the delivery system that would most benefit their patients.

RESULTS

Of the 1000 physicians, 294 returned the questionnaire, giving a response rate of 29%. Of these, 16 physicians returned blank surveys, leaving 278 for analysis. Two hundred forty-nine (90%) valued off-site, delayed interpretation of mammographic screening for their patients over on-site reading by a single radiologist if an off-site, delayed reading made double reading possible.

CONCLUSION

An off-site, double-reading delivery system for mammographic screening services is preferred by many physicians for their patients once they are educated as to the benefits of double reading.

Cytomegalovirus causing acute colonic pseudo-obstruction in a renal transplant recipient

A female patient presented with pyrexia and features of large intestinal obstruction, 10 weeks posttransplantation, with biopsy-proven colitis caused by cytomegalovirus (CMV) and positive CMV antigenaemia and IgM tests. The symptoms resolved after treatment with ganciclovir, nasogastric aspiration and intravenous fluid replacement.

Factors influencing plasma lipid profiles including lipoprotein (a) concentrations in renal transplant recipients

Fasting plasma cholesterol, triglycerides, high-density lipoprotein (HDL) and apoprotein (apo) B were elevated in 214 nondiabetic renal transplant recipients when compared to a reference group. Apo (a) was slightly but not significantly lower in transplant recipients (median 118 mg/dl, range 16-1680 vs 130 mg/dl, 10-1176) and this difference could be predicted from Lp (a) isoform analysis. Cholesterol, triglyceride, apo B and apo (a) concentrations correlated negatively with creatinine clearance but none of these parameters showed a significant association with proteinuria. Patients treated with steroids had higher plasma HDL concentrations than those receiving cyclosporin monotherapy (P < 0.01). The use of diuretics was associated with raised triglycerides (P < 0.001) and cholesterol (P < 0.01) and with reduced HDL (P < 0.01) whilst patients receiving beta-blockers had significantly higher triglycerides (P < 0.01) and lower HDL levels (P < 0.02). In multiple regression analysis, age (P < 0.01), creatinine clearance (P < 0.05) and diuretic therapy (P < 0.005) were independent risk factors for increased cholesterol whilst apo (a) levels correlated negatively with creatinine clearance (P < 0.005). These results suggest that impaired renal function, steroids and non-immunosuppressive drugs contribute to lipid abnormalites in renal transplant recipients.

Cytomegalovirus involving gastrointestinal tract in renal transplant recipients

Infection due to cytomegalovirus (CMV) is a substantial cause of mortality and morbidity among renal transplant recipients but the prognosis of the disease has changed dramatically since the introduction of ganciclovir (GAN). During a period of 5 years we treated 54 patients who developed CMV disease. From this group of patients we identified 7 patients with primary gastrointestinal tract (GIT) CMV disease who received treatment with GAN. Tissue diagnosis was made by endoscopy of the upper GIT (6 patients) or sigmoidoscopy (one patient) and histological examination. All patients improved after treatment with GAN; three patients required additional treatment for recurrent CMV disease and recovered, and 1 patient relapsed without GIT involvement (P = 0.014). Recurrent CMV disease was more severe (mean score of 15 in relapse compared to 7 in the first episode). We believe relapse to be more common and the disease to be more severe in the presence of GIT involvement suggesting that a longer duration of treatment with GAN may be required in this clinical manifestation of CMV disease.

In vitro and in vivo persistence of reticulocytes from donor red cells

BACKGROUND

Reticulocytes are important in the phenotyping of transfused patients. Reticulocytes can persist in blood units for the shelf life of the unit.

STUDY DESIGN AND METHODS

Temperature dependence of reticulocyte persistence was examined in vitro at 4, 24, and 37 degrees C by using thiazole orange staining and flow cytometric analysis. Two-color flow cytometric analysis was used to evaluate the persistence of donor reticulocytes in transfused patients.

RESULTS

Flow cytometric analysis using thiazole orange demonstrated that persistence of reticulocytes in units of stored CPDA-1 blood was temperature-dependent. Reticulocytes disappeared over 13 and 6 days at 24 degrees C and 37 degrees C, respectively, but at 4 degrees C the reticulocyte count changed little over 35 days. Two-color flow cytometric analysis of reticulocyte antigens was used to follow donor reticulocytes in 14 transfusion events in nine different patients. Donor reticulocytes persisted through 24 hours in 75 percent of the patients and were detectable at 48 hours in three patients.

CONCLUSION

This study demonstrates that reticulocytes persist during refrigerated storage; they are detectable in the circulation of most recipients for the first 24 hours after transfusion and in the circulation of a few recipients after 48 hours. These findings may have relevance for separation techniques based on reticulocyte density in samples drawn shortly after transfusion and for evaluation of reticulocyte counts in patients with hematologic abnormalities.

HLA-DQ gene polymorphism in primary IgA nephropathy in three European populations

MHC Class II genes may contribute to susceptibility to IgA nephropathy (IgAN). We have previously identified a restriction fragment length polymorphism (RFLP) of the DQB1 region that associated with IgAN in British Caucasoids. However, another group, while demonstrating a DQB1 association, was unable to confirm our finding. MHC molecules are heterodimers consisting of an alpha and beta chain, and thus polymorphism of the DQA1 alpha chain may also be important to disease pathogenesis in IgAN. Therefore, we have determined DQA1 alleles and re-examined DQB1 alleles in British Caucasoids with IgAN using an approach that can differentiate between the common DQ alleles; we have also extended our studies to Caucasoid populations from Northern and Southern Europe, thereby addressing the possibility of variation in genetic susceptibility between populations. DNA was prepared from IgAN patients (British, N = 105; Italian, N = 71; Finnish, N = 48) and healthy controls (British, N = 111; Italian, N = 63; Finnish, N = 41). DQA1 alleles were identified by TaqI RFLP and Southern blotting; alleles that could not be fully resolved by Taq Southern blotting were identified by PCR-RFLP. DQB1 alleles were identified by polymerase chain reaction (PCR) based technique (PCR-RFLP). No consistent association of DQ alleles were found between the populations studied. In British patients a decreased frequency of DQB1*0201 was observed (P = 0.008), in Finnish patients a decreased frequency of DQB1*0602 was observed (P = 0.01), and in Italian patients no association between DQ markers and IgAn was found. These data demonstrate population variation in disease association, but no strong or consistent association in the DQ region.

UK multicentre study to assess the safety and tolerability of Neoral in stable renal transplant patients. UK Neoral Study Group

The safety and tolerability of transferring maintained renal transplant patients from Sandimmun to Neoral is being assessed in a multicentre, open-label, single-arm study. A total of 250 patients has been enrolled and results are available from 75 patients up to 12 months post-transfer. A slight trend to higher mean cyclosporin trough levels was seen in this cohort, but trough levels were unchanged in the sub-group receiving > or = 1 dose changes. The mean dose fell by 13%. Creatinine levels showed a slight overall upward trend. Blood pressure and uric acid were unchanged and adverse events were typical of those seen with Sandimmun. Neoral was well-tolerated. Data from the full cohort of 250 patients up to 3 months post-transfer support these findings. These results indicate that transfer from Sandimmun to Neoral is safe and well-tolerated and provides appropriate immunosuppression at a lower average dose than Sandimmun. The Neoral dose should be adjusted promptly, as required, to maintain the target trough level.

Ligand-stimulated beta 2-adrenergic receptor internalization via the constitutive endocytic pathway into rab5-containing endosomes

The small GTPase rab5 appears to be rate-limiting for the constitutive internalization of transferrin receptor and for fluid-phase endocytosis. However, it is unknown whether rab5 regulates receptors whose internalization is stimulated by the binding of ligand, and whether such receptors change the underlying rate of the endocytic pathways they utilize. As a model for ligand-stimulated endocytosis, we used transfected HEK293 cells expressing high levels of an epitope-tagged human beta 2-adrenergic receptor. Nearly all receptors were on the cell surface in the absence of agonist, but within ten minutes of agonist addition &gt; 50% of receptors internalized and colocalized extensively with rab5. Hypertonic sucrose blocked beta 2-adrenergic receptor internalization, as well as that of transferrin receptor, suggesting a clathrin-mediated process. In contrast, an inhibitor of potocytosis had little effect upon beta 2-adrenergic receptor internalization, suggesting that this process did not require active caveolae. Consistent with this finding, caveolin was not detectable in the 12 beta 6 line, as assessed by western blotting with a polyclonal anti-caveolin antibody. Stimulated receptor internalization did not affect the rate or capacity of the constitutive endocytic pathway since there was no detectable increase in fluid-phase endocytosis after addition of beta-agonist, nor was there a significant change in the amount of surface transferrin receptor. Altogether, these data suggest that beta 2-adrenergic receptors internalize by a clathrin-mediated and rab5-regulated constitutive endocytic pathway. Further, agonist-stimulated receptor internalization has no detectable effect upon the function of this pathway.

Real-time monitoring of renal function during ischemic injury in the rhesus monkey

The presence of delayed graft function (DGF) following cadaver donor renal transplantation is associated with inferior graft survival as well as decreased patient survival. Delay in onset of function eliminates a valuable indicator of allograft viability, which is not easily replaced by standard diagnostic procedures. The purpose of this study was to demonstrate that a new clearance technique could be used to measure renal function minute to minute and under conditions similar to those observed in humans in the immediate posttransplantation period. A monkey model was used to provide controlled conditions. Increasing levels of ischemic injury were produced in 12 Rhesus monkeys by renal hilum cross-clamping. Real-time measurements of glomerular filtration rate (GFR) were obtained from the rate of clearance of the extracellular fluid of the GFR agent 99mTc-DTPA, as measured with a specially designed external radioactivity counting device called the ambulatory renal monitor, or ARM. GRF was measured every 2-5 min as the slope (k) of the log of activity measured minute to minute versus time. GFR measurements were correlated with blood urea nitrogen (BUN), plasma creatinine (Cr), routine light microscopy, and measurement of proliferating cell nuclear antigen (PCNA), a marker of cell proliferation. Large changes in renal function due to ischemia or ureteral obstruction were observed within minutes. In addition, the rate constant on Day 1 was predictive of peak serum Cr(R =--0.86, R2=.74, p = .0001). Acute tubular necrosis (ATN) resolution was reflected more quickly when using the rate constant (Day 1) than when using either BUN or plasma Cr (Day 3-4). Because of renal functional reserve, BUN and plasma Cr were relatively insensitive indicators of mild to moderate reductions in GFR as compared with the rate constant. We conclude that ARM is a simple method which provide an accurate, near real-time GFR readout with potential applications not only for the clinical management of patients with DGF, but also as a research tool in acute renal failure (ARF).

Blood lead surveys of communities in proximity to lead-containing mill tailings

In former mining communities tailings containing up to 2% (20,000 ppm) lead (Pb), frequently as galena (lead sulfide), may be present in large piles near residences, as landfill under homes, or mixed with residential soils. The impact of tailings on blood lead was assessed by comparing blood lead values obtained from residents and environmental lead measured in soils and tailings piles. Data from 13 communities were compiled. Approximately 2995 blood lead measurements were available from persons residing on or near tailings, with the majority of samples from children. Blood lead levels were compared to 1806 controls from nearby communities, national norms, and communities with active smelters. Data comparisons indicated that blood lead values in tailings residents were usually comparable to controls. These data suggest that lead present in mill tailings is not readily bioavailable, even to children who played in dirt or tailings piles. Consequently, the hazard of lead in soils appears to be site-specific and influenced by bioavailability; the bioavailability of galena tailings to humans is low. When health risks of lead soils are predicted, factors affecting the bioavailability of lead present in tailings need to be taken into account.

Use of a palmtop pocket computer to produce a customised logbook of surgical experience

The use of a pocket palmtop computer for the prospective audit of a basic surgical trainee's operative experience is described. A powerful yet portable system of information storage is shown, which can be used to compile a logbook suitable for examinations and career interviews in clinical surgery.