Renal cortical cholesterol accumulation is an integral component of the systemic stress response

BACKGROUND

Direct tubular injury (such as ischemia or myohemoglobinuria) increases renal cortical cholesterol content. This study explored whether systemic forms of stress (such as heat shock or sepsis) can trigger renal cholesterol accumulation, and if so, whether increased 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (HMGCR) expression might be involved.

METHODS

Male CD-1 mice were subjected to glycerol-induced myohemoglobinuria (MH), systemic heat shock (HS), or E. coli sepsis. Free cholesterol (FC), cholesteryl esters (CE), and HMGCR (Western blot) levels were assessed 18 hours later. Statin effects on renal cholesterol levels and on the severity of MH-acute renal failure (ARF) were also determined.

RESULTS

Sepsis and HS each induced dramatic FC and CE increments, comparable to those observed with myohemoglobinuria, and without inducing acute tubular necrosis (ATN). Part of the cholesterol increments was localized within plasma membrane (detergent resistant) microdomains (for example, rafts/caveolae). HS and MH each increased renal HMGCR, as well as HS protein (HSP-72) expression. Oxidant stress (Fe) imposed on cultured proximal tubule (HK-2) cells also enhanced HMGCR content. Conversely, sepsis did not raise renal HMGCR or HSP-72 levels. Statin therapy decreased the severity of MH-ARF and renal cholesterol content. However, this appeared to arise from a statin-mediated decrease in glycerol-induced extrarenal tissue damage (myolysis/LDH release).

CONCLUSIONS

Cholesterol appears to be a renal 'acute phase reactant' with tissue levels increasing with either systemic stress (such as, heat shock, sepsis), or direct tissue damage (such as ATN). Increased HMGCR expression can contribute to this result. Mechanisms other than HMGCR induction also can mediate stress-induced cholesterol increments (for example, in the case of sepsis), and statins can mitigate MH-ARF. However, systemic anti-inflammatory effects, rather than a primary renal action, appear more likely to be involved.

Measuring later health status of high risk infants: randomised comparison of two simple methods of data collection

OBJECTIVE

To test two methods of providing low cost information on the later health status of survivors of neonatal intensive care.

DESIGN

Cluster randomised comparison.

SETTING

Nine hospitals distributed across two UK health regions. Each hospital was randomised to use one of two methods of follow up.

PARTICIPANTS

All infants born

METHOD

Families were recruited at the time of discharge. In one method of follow up families were asked to complete a questionnaire about their child's health at the age of 2 years (corrected for gestation). In the other method the children's progress was followed by clerks in the local community child health department by using sources of routine information.

RESULTS

236 infants were recruited to each method of follow up. Questionnaires were returned by 214 parents (91%; 95% confidence interval 84% to 97%) and 223 clerks (95%; 86% to 100%). Completed questionnaires were returned by 201 parents (85%; 76% to 94%) and 158 clerks (67%; 43% to 91%). Most parents found the forms easy to complete, but some had trouble understanding the concept of "corrected age" and hence when to return the form. Community clerks often had to rely on information that was out of date and difficult to interpret.

CONCLUSION

Neither questionnaires from parents nor routinely collected health data are adequate methods of providing complete follow up data on children who were born preterm and required neonatal intensive care, though both methods show potential.

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MESH Headings

• Community Health Services/methods
• Costs and Cost Analysis
• Data Collection/economics
• Data Collection/methods
• Follow-Up Studies
• Health Status Indicators
• Humans
• Infant, Newborn
• Infant, Premature
• Intensive Care, Neonatal
• Parents
• Prognosis
• Reproducibility of Results
• Surveys and Questionnaires

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Adenotonsillectomy in children: a comparison of morphine and fentanyl for peri-operative analgesia

This study compared the effectiveness and side-effects of intra-operative fentanyl with fentanyl and morphine for elective adenotonsillectomy in a double-blind study, in 60 children randomly allocated to receive either intravenous fentanyl 1 microg x kg(-1) intra-operatively or intramuscular morphine 100 microg x kg(-1) at induction. All children received a standard anaesthetic induction with intravenous fentanyl 1 microg x kg(-1) and propofol 4-5 mg x kg(-1) and maintenance with oxygen, nitrous oxide and isoflurane. Pain scores, emetic episodes and supplemental morphine requirements were recorded for 24 h postoperatively. The overall incidence of postoperative vomiting was high in both groups: 70% in the fentanyl group and 78% in the morphine group. The incidence of postoperative vomiting was lower in the fentanyl group (p < 0.03) in the first 4 h, but similar by 24 h. Children who received morphine at any time in the first 24 h had more median (range) episodes of vomiting [2 (0-7)] than children receiving fentanyl only [l (0-3); p < 0.03]. Administration of rescue anti-emetics, pain scores in recovery and pain scores over the next 24 h were similar between the two groups.

Structures of porcine beta-trypsin-detergent complexes: the stabilization of proteins through hydrophilic binding of polydocanol

Polydocanol has a wide range of medical applications, especially in sclerotherapy of many diseases such as gastrointestinal antiplastia, oesophageal haemangioma etc. It is of interest to study the mode of binding of this medically important detergent and its subsequent action on proteins. Here, three crystal structures of serine protease trypsin are reported in the presence of varying concentrations of polydocanol in order to elucidate its mode of binding and interactions with proteins. Polydocanol binds to the protein with its hydrophilic head rather than the hydrophobic tail as is the case with other detergents such as SDS and MEGA-8. This hydrophilic binding mode results in the binding sites of polydocanol being distributed on the surface of the enzyme. There are at least 11 binding sites for polydocanol in trypsin. Polydocanol forms part of the large-scale water networks which connect distant regions of the enzyme, thereby stabilizing it. The hydrophilic binding of polydocanol also results in cross-linked pairs of trypsin molecules.

Congenital disorders of glycosylation type I leads to altered processing of N-linked glycans, as well as underglycosylation

The N-linked glycans on transferrin and alpha(1)-antitrypsin from patients with congenital disorders of glycosylation type I have increased fucosylation and branching relative to normal controls. The elevated levels of monofucosylated biantennary glycans are probably due to increased alpha-(1-->6) fucosylation. The presence of bi- and trifucosylated triantennary and tetra-antennary glycans indicated that peripheral alpha-(1-->3), as well as core alpha-(1-->6), fucosylation is increased. Altered processing was observed on both the fully and underglycosylated glycoforms.

Magnetic resonance imaging-guided core needle biopsy and needle localized excision of occult breast lesions

BACKGROUND

Breast magnetic resonance imaging (MRI) has been reported to be twice as sensitive and three times more specific in detecting breast cancer. We report a series of MRI-guided stereotactic breast biopsies (SCNBB) and needle localized breast biopsies (NLBB) to evaluate MRI as a localization tool.

METHODS

Forty-one breast lesions were identified in 39 patients who subsequently had SCNBB or NLBB. Suspicious areas of enhancement were stereotactically biopsied with 16-G core biopsy needles or localized with 22-G wires for excision under laser guidance.

RESULTS

Forty-one breast lesions were identified from 1,292 breast MRIs. SCNBB identified three malignancies and two areas of atypia. Two additional cancers were found after NLBB. In patients having NLBB alone, five cancers and two areas of atypia were identified.

CONCLUSIONS

In this initial series, breast MRI-guided SCNBB and NLBB were valuable tools in the management of patients with suspicious abnormalities seen only on MRI.

Antigen, allele, and haplotype frequencies report of the ASHI minority antigens workshops: part 1, African-Americans

HLA typing was performed on 977 African Americans residing throughout most of the United States. Class I and class II antigens and class II alleles were defined for all individuals and class I alleles were determined for a subset of individuals. The occurrence of 854 of the individuals in family groups permitted direct counting of allele and haplotype frequencies. The data were analyzed for antigen, allele, and haplotype frequencies; recombination frequencies; segregation distortion; distribution of haplotype frequencies; linkage disequilibria; and geographic distribution of DR antigens. Tables of the antigen, allele, the most common two and three point haplotypes, and 88 extended haplotypes that include class I and class II alleles are presented. Notable findings include a lower than expected frequency of recombination between the B and DR loci (theta= 0.0013), lower than expected frequency of inheritance (44.5% vs 54.5%) of the DRB1*1503; DQB1*0602 haplotype, lower than anticipated linkage disequilibrium values for DR; DQ haplotypes, and a skewed geographic distribution of DR antigens.

Cerebral palsy, low birthweight and socio-economic deprivation: inequalities in a major cause of childhood disability

There is currently little and conflicting evidence concerning the existence of socio-economic inequalities in cerebral palsy prevalence, or the extent to which this is influenced by socio-economic inequalities in low birthweight, a strong risk factor for cerebral palsy. The study is based on 753 children registered with cerebral palsy, resident in the former Oxford Regional Health Authority area and born in the years 1984-90. Two population definitions were used: 1. Children with cerebral palsy resident at birth in the area, with resident births as denominator, 2. Children with cerebral palsy resident at age 5 in the area, with children of ages 1-7 resident in the area in the 1991 census as denominator. Children with cerebral palsy and all births/children were classified according to the Carstairs area deprivation index (grouped into quintiles) of their ward of residence. The prevalence among residents at birth varied from 2.08 per 1000 births in the most affluent quintile to 3.33 in the most deprived quintile (trend P < 0.001). Although there was a tendency for children to move to more affluent areas during early childhood, the socio-economic gradient was similar at age 5. A greater proportion of births in the more deprived quintiles were of low or very low birthweight, the proportion rising from 5.6% in the most affluent quintile to 8.2% in the most deprived. Within the normal birthweight category there was a trend for higher prevalence of cerebral palsy in more deprived quintiles, from 1.29 per 1000 in the most affluent quintile to 2.42 in the most deprived quintile (trend P < 0.001). Within the low birthweight and very low birthweight groups, separately or combined, there was no evidence of any relationship between cerebral palsy prevalence and deprivation. We estimate that up to 17% of cerebral palsy cases might be "preventable" in terms of the reduction to be expected if the whole population had the rate of cerebral palsy of the most affluent quintile. Although the strong socio-economic gradient for cerebral palsy was restricted to the normal birthweight category, we estimate that two-thirds of the excess cases in the population associated with greater socio-economic deprivation were normal birthweight cases, and one-third were low birthweight cases owing to the greater prevalence of low birthweight in more deprived populations. The pattern of socio-economic inequalities should be further explored in other regions, and should be taken into account in aetiological research, and in the effective delivery and evaluation of services.

Analysis and occurrence of polybrominated diphenyl ethers in Washington state freshwater fish

A method is described for analyzing polybrominated diphenyl ethers (PBDEs) in fish tissue using gas chromatography with atomic emission detection (GC/AED) and quantitation by compound independent calibration (CIC). The method has the advantage of an element-selective response, including selectivity between bromine and chlorine. An analysis of fish tissue samples from selected locations in Washington State showed total PBDE concentrations ranged from 1.4 microg/kg (wet weight) in rainbow trout from a remote spring-fed stream to 1,250 microg/kg in mountain whitefish from the urbanized Spokane River. Tetra and penta isomers were the major compounds present. There appear to be substantial between-species differences in the ability of fish to metabolize PBDEs.

Public health advocacy--determining a role for staff of a public hospital

This study explored the public health advocacy role of staff employed at a major South Australian specialist public hospital that had made an organisational commitment to health promotion. It was concluded that staff did have a role to play in public health advocacy, though the issues pursued primarily related to disease and injury prevention rather than the broader social determinants of health. Staff gained valuable experience in the political processes of public health advocacy. The hospital had to develop organisational infrastructures to support staff so they could undertake public health advocacy on behalf of the hospital. It was also necessary for the hospital to implement other changes in order to 'get its own house in order' before issues could be addressed in the broader community.

Randomized, controlled trial of acetazolamide and furosemide in posthemorrhagic ventricular dilation in infancy: follow-up at 1 year

OBJECTIVE

Posthemorrhagic ventricular dilation (PHVD) is a complication of intraventricular hemorrhage in preterm infants and is associated with a high risk of long-term disability. Furosemide and acetazolamide are used widely in the treatment of PHVD in the hope of avoiding the need for placement of a ventriculoperitoneal shunt, but these drugs have not been evaluated in a controlled trial. This article reports a multicenter, randomized, controlled trial designed to test the hypothesis that these drugs would reduce the rate of shunt placement (or death) and increase survival to 1 year of age without disability.

METHODS

Between 1992 and 1996, 177 infants who were less than 3 months past term and had ventricular width >4 mm above the 97th centile following intraventricular hemorrhage were assigned randomly to either standard therapy or standard therapy plus drug therapy with acetazolamide (100 mg/kg/d) plus furosemide (1 mg/kg/d). Infants who were enrolled in the trial had a median gestational age of 28.6 weeks and were enrolled at a mean postnatal age of 3.6 weeks. Forty-four percent were reported to have a cerebral parenchymal lesion on ultrasound scan at randomization. The primary outcome measure of death or shunt placement (known in all but 1 infant) occurred in 56 of 88 infants who were allocated to drug plus standard therapy compared with 46 of 88 who were allocated to standard therapy. The risk ratio was 1.23 (95% confidence interval: 0.95-1.59). Neurodevelopmental outcome information at a corrected age of 1 year (known in all but 3 of 149 surviving infants) included disability or neuromotor impairment in 54 of 67 infants (81%) who were allocated to drug plus standard therapy and 52 of 69 infants (66%) who were allocated to standard therapy. Seventy-two of 85 infants (85%) who were allocated to drug therapy either died or were disabled or impaired at 1 year compared with 62 of 89 infants (70%) who were treated with standard therapy (risk ratio: 1.22; 95% confidence interval: 1.03-1.4376). The excess risk of these adverse outcomes was greater among infants who did not have a cerebral parenchymal lesion seen on ultrasound examination at trial entry.

CONCLUSIONS

These results suggest that the use of acetazolamide and furosemide in preterm infants with PHVD is ineffective in decreasing the rate of shunt placement and is associated with increased neurologic morbidity. This treatment therefore cannot be recommended.

Health promoting hospitals: a typology of different organizational approaches to health promotion

This paper draws on a review of the literature about the types of health promotion activities conducted by health promoting hospitals and an observation of how some Australian hospitals have structured the organizational arrangements to be more health promoting. This paper also draws on the experiences of one of the authors (A.J.) in managing and evaluating an organizational change process at a major specialist hospital in Adelaide, South Australia, that sought to re-orientate the hospital towards placing more emphasis on health promotion. From these three sources, a typology of four approaches of organizational arrangement to health promotion is presented. These approaches are: 'doing a health promotion project'; 'delegating it to the role of a specific division, department or staff'; 'being a health promotion setting'; and 'being a health promotion setting and improving the health of the community'. For the re-orientation of the specialist hospital to occur and be sustainable, the research indicated that over the case study period of 1994-1998 there had to be strong organizational commitment to change, supported at multiple levels of the organization, and reflected in policy and practice change. The paper concludes that more evaluative research of this type will be important if the rhetoric of healthy settings is to become a reality.

Pulse oximetry in sickle cell anemia

OBJECTIVES

To determine whether pulse oximetry is accurate and if it correlates with arterial blood gas saturation in pediatric patients with sickle cell anemia.

DESIGN

Prospective, comparative study using a convenience sample of patients with sickle cell anemia who had simultaneous arterial blood gas sampling and pulse oximetry.

SETTING

Children's Memorial Hospital, a large tertiary care pediatric hospital in Chicago, IL. Patients selected from the emergency department and the pediatric intensive care unit.

PATIENTS

Twenty-four consecutive patients with sickle cell anemia who had simultaneous arterial blood gas sampling and pulse oximetry.

MEASUREMENTS AND MAIN RESULTS

Twenty-four patients had a total of 70 simultaneous pulse oximeter and blood gas pair samples. Each patient's initial pulse oximeter/blood gas pair was used in the statistical analysis. Three patients had venous samples and were excluded from comparison, leaving 21 arterial blood gas/pulse oximeter pairs for analysis. The pulse oximeter correlated well with the cooximeter-measured arterial saturation (r(2) =.74). The pulse oximeter significantly underestimated saturation by a mean of -1.6% (95% confidence interval, -0.3 to -3; p =.03).

CONCLUSIONS

Pulse oximetry correlates well with cooximeter-measured saturation in patients with sickle cell anemia. Pulse oximetry significantly underestimates true arterial saturation, but the bias is clinically insignificant. Pulse oximetry can be used reliably to estimate the arterial oxygen saturation in patients with sickle cell anemia.

Prospective assessment of tizanidine for spasticity due to acquired brain injury

OBJECTIVE

To determine if orally delivered tizanidine will control spastic hypertonia due to acquired brain injury.

DESIGN

Randomized, double-blind, placebo-controlled, crossover design, with 2 8-week treatment arms separated by a 1-week washout period at baseline. Patients were randomly assigned to receive tizanidine or a matching placebo.

SETTING

Tertiary care outpatient and inpatient rehabilitation center attached to a university hospital.

PARTICIPANTS

Seventeen persons recruited in a consecutive manner, 9 of whom had suffered a stroke and 8 a traumatic brain injury, and had more than 6 months of intractable spastic hypertonia.

INTERVENTION

Over a 6-week period, subjects were slowly titrated up to their maximum tolerated dose (up to 36 mg/d). Following a 1-week drug taper and 1-week period in which no study drug was administered, patients were then crossed over to the other study medication following an identical titration regime.

MAIN OUTCOME MEASURES

Subjects were evaluated for dose and effect throughout the trial as well as for side effects. Data for Ashworth rigidity scores, spasm scores, deep tendon reflex scores, and motor strength were collected on the affected upper extremity (UE) and lower extremity (LE). Differences over time were assessed via descriptive statistics, Friedman's analysis, and Wilcoxon's signed-rank. Data are reported as the mean +/- 1 standard deviation.

RESULTS

Following 4 weeks of treatment when subjects reached their maximal tolerated dosage, the average LE Ashworth score on the affected side decreased from 2.3 +/- 1.4 to 1.7 +/- 1.1 (p <.0001). The spasm score decreased from 1.0 +/- 0.9 to 0.5 +/- 0.8 (p =.0464), while the reflex score was not statistically significant decreasing from 2.2 +/- 1.0 to 2.0 +/- 1.1 (p =.0883). The average UE Ashworth score on the affected side decreased from 1.9 +/- 1.1 to 1.5 +/- 0.9 (p <.0001). There was no significant change in the UE spasm and reflex scores. While there were positive placebo effects on motor tone, the active drug was still significantly better than placebo for decreasing LE tone (p =.0006) and UE tone (p =.0007). With a reduction in motor tone, there was an increase in motor strength (p =.0089). The average dosage at 4 weeks was 25.2mg/d.

CONCLUSION

Tizanidine is effective in decreasing the spastic hypertonia associated with acquired brain injury, which is dose-dependent. There are limitations on its use due to side effects related to drowsiness.

Ethylene glycol-mediated tubular injury: identification of critical metabolites and injury pathways

Ethylene glycol (EG) intoxication produces multisystem organ injury, including acute renal failure. Although EG must be metabolized to toxic intermediates to induce organ damage, the specific metabolite(s) responsible and the underlying pathogenic mechanisms remain poorly defined. To explore these issues, isolated mouse proximal tubular segments (PTSs) were incubated with either varying doses of EG or its prime metabolites (glycolate, glycoaldehyde, glyoxylate, or oxalate for 15 to 60 minutes). Injury was assessed by the percentage of lactate dehydrogenase (LDH) release, LDH destruction, adenosine triphosphate (ATP) depletion, or membrane phospholipid degradation. Toxicities were also assessed in cultured HK-2 cells over 18 hours (by MTT assay). EG, glycolate, and oxalate did not induce overt PTS injury. Conversely, glyoxylate and glycoaldehyde were highly toxic, causing profound ATP depletion and LDH release. Glycoaldehyde also caused enzyme (LDH) and selected phospholipid degradation (phosphatidylethanolamine, phosphatidylserine). These changes were not seen with glyoxylate treatment. Acidosis (pH 6.8) and glycine (2 mmol/L) each blocked glyoxylate, but not glycoaldehyde toxicity, indicating differing injury pathways. Only glycoaldehyde and glyoxylate induced marked HK-2 cell death. We conclude that glycoaldehyde and glyoxylate are the principal metabolites responsible for EG nephrotoxicity and do so by causing ATP depletion and phospholipid and enzyme destruction. Glycine and acidosis, by-products of EG metabolism, can attenuate glyoxylate-mediated injury. This suggests that naturally occurring but incomplete protective pathways may be operative during the evolution of EG cytotoxicity.