RPR 106541, a novel, airways-selective glucocorticoid: effects against antigen-induced CD4+ T lymphocyte accumulation and cytokine gene expression in the Brown Norway rat lung

1. The effects of a novel 17-thiosteroid, RPR 106541, were investigated in a rat model of allergic airway inflammation. 2. In sensitized Brown Norway rats, challenge with inhaled antigen (ovalbumin) caused an influx of eosinophils and neutrophils into the lung tissue and airway lumen. In the lung tissue there was also an accumulation of CD4+ T lymphocytes and increased expression of mRNA for interleukin-4 (IL-4) and IL-5, but not interferon-gamma (IFN-gamma). These findings are consistent with an eosinophilia orchestrated by activated Th2-type cells. 3. RPR 106541 (10-300 microg kg[-1]), administered by intratracheal instillation into the airways 24 h and 1 h before antigen challenge, dose-dependently inhibited cell influx into the airway lumen. RPR 106541 (100 microg kg[-1]) caused a significant (P<0.01) (98%) inhibition of eosinophil influx and a significant (P<0.01) (100%) inhibition of neutrophil influx. RPR 106541 was approximately 7 times and 4 times more potent than budesonide and fluticasone propionate, respectively. 4. When tested at a single dose (300 microg kg[-1]), RPR 106541 and fluticasone each caused a significant (P<0.01) (100%) inhibition of CD4+ T cell accumulation in lung tissue. Budesonide (300 microg kg[-1]) had no significant effect. RPR 106541 and fluticasone (300 microg kg[-1]), but not budesonide (300 microg kg[-1]), significantly (P<0.05) inhibited the expression within lung tissue of mRNA for IL-4. RPR 106541 (300 microg kg[-1]) also significantly (P<0.05) inhibited expression of mRNA for IL-5. 5. The high topical potency of RPR 106541 in this model, which mimics important aspects of airway inflammation in human allergic asthmatics, suggests that this glucocorticoid may be useful in the treatment of bronchial asthma.

Molecular interactions between Hb alpha-G Philadelphia, HbC, and HbS: phenotypic implications for SC alpha-G Philadelphia disease

We show here that alpha2(G-Phila.) beta2(C) has an increased rate of crystal nucleation compared to alpha2 beta2(C) (HbC). We conclude from this finding that position alpha68, the mutation site of alpha2(G-Phila.) beta2 (HbG(Philadelphia)), is a contact site in the crystal of HbC. In addition, that HbS enhances HbC crystallization (additive to the effect of alpha(G-Phila.) as shown here) and that alpha(G-Phila.) inhibits polymerization of HbS are pathogenically relevant previously known facts. All of these findings help explain the phenotype of an individual simultaneously heterozygous for the betaS, betaC, and the alpha(G-Phila.) genes (SC alpha-G Philadelphia disease). This disease is characterized by a mild clinical course, abundant circulating intraerythrocytic crystals, and increased folded red cells. This phenotype seems to be the result of increased crystallization and decreased polymerization brought about by the opposite effects of the gene product of the alpha(G-Phila.) gene on the betaC and betaS gene products. Some of the intraerythrocytic crystals in this syndrome are unusually long and thin, resembling sugar canes, unlike those seen in SC disease. The mild clinical course associated with increased crystallization implies that, in SC disease, polymerization of HbS is pathogenically more important than the crystallization induced by betaC chains. The SC alpha-G Philadelphia disease is an example of multiple hemoglobin chain interactions (epistatic effect among globin genes) creating a unique phenotype.

Sudden cardiac death in familial hypertrophic cardiomyopathy: are "benign" mutations really benign?

Familial hypertrophic cardiomyopathy (FHC) is an autosomal dominant disorder characterised predominantly by left ventricular hypertrophy and sudden cardiac death. Mutations in the cardiac beta-myosin heavy chain gene have been identified in several families and designated as "benign" or "malignant". We describe a family (family L) with a "benign" mutation in which early sudden cardiac death has occurred. The family was studied by clinical, electrocardiographic and echocardiographic assessment. DNA analysis involved screening for the six most common cardiac beta-myosin heavy chain gene mutations using allele specific oligonucleotide probes and restriction enzyme analysis. The Val606Met missense mutation was found. This mutation has been described in four families as being "benign" since it was associated with low penetrance and a near normal life span. Sudden cardiac death was an infrequent finding. In contrast, family L has a more malignant clinical picture with one sudden death in three affected individuals. The proband died suddenly at age 14 years during exercise. Designating gene mutations in FHC as benign or malignant has major clinical implications. As these mutations have only been described in a limited number of families, caution needs to be taken when interpreting genotype-phenotype correlations in this disorder.

Anti-inflammatory 17beta-thioalkyl-16alpha,17alpha-ketal and -acetal androstanes: a new class of airway selective steroids for the treatment of asthma

The synthesis and anti-inflammatory potencies of a new class of 17beta-thioalkyl-16alpha,17alpha-ketal and -acetal androstanes are described. This new class of steroids was made by fragmentation of 2-thioxo-1,2-dihydropyrid-1-yl esters of the corresponding 17-acids to the 17-radical. The radical generated was trapped using a variety of radicophilic disulfides, giving a steroidal D-ring having acetal or ketal functionality at C-16 and C-17, together with a sulfide link at C-17. Compounds from this series bind to the glucocorticoid receptor with high potency and are functional agonists as measured by their ability to induce tyrosine aminotransferase activity in a rat hepatic cell line in vitro. These 17beta-thioalkyl androstanes potently inhibit Sephadex-induced rat lung inflammation when administered directly into the airways. The high topical potency, together with a low propensity to induce systemic glucocorticoid-like side effects (rat thymus involution), provides the present compounds with a high degree of airway selectivity compared with currently available inhaled glucocorticoids. The presently described 17beta-thioalkyl-16alpha,17alpha-ketal androstanes may be useful for therapies for inflammatory diseases such as asthma.

Drug management in skin surgery

Lidocaine (lignocaine) 1% with epinephrine (adrenaline) 1:200,000 (maximum dose 40mL) is the agent of choice in skin surgery. It can be used at all sites except the fingers, toes and penis, where epinephrine should be avoided. Epinephrine-induced vasoconstriction delays local anaesthetic clearance, thus prolonging its effect and, by reducing peak blood lidocaine concentrations, enables a higher maximum dose to be used. Adding epinephrine, however, introduces the possibility of a drug interaction with tricyclic antidepressants and nonselective beta-blockers. Also, injection pain is greater because of the acidic sodium metabisulphite that has to be added to prevent epinephrine oxidation. Injection pain can be reduced by buffering the solution using sodium bicarbonate. There are no drug interactions that prevent the use of plain lidocaine: injection pain is least with 0.5% solutions. Injection of large volumes of very dilute lidocaine solutions (tumescent anaesthesia) enables higher maximum doses of lidocaine to be tolerated and large areas to be anaesthetised by infiltration. Amethocaine gel is a faster acting and more effective topical anaesthetic compared with eutectic lidocaine-prilocaine cream, but is a topical sensitiser. In high risk patients, prophylactic antibiotics should be given to prevent bacterial endocarditis when operating on infected lesions and on potentially colonised crusted lesions in high-risk patients (i.e. those with prosthetic heart valves). Wound infections following surgery on infected skin lesions can be prevented by the prophylactic use of mupirocin ointment. Aspirin-induced inhibition of platelet adhesion results in bleeding complications in approximately 15% of skin surgery patients receiving aspirin. Patients whose bleeding time is > 8 minutes are particularly at risk, and aspirin should be stopped at least 7 days prior to surgery in these patients. Aspirin can be continued in other patients without serious bleeding complications.

Prospective, randomized trial of two antiseptic solutions for prevention of central venous or arterial catheter colonization and infection in intensive care unit patients

OBJECTIVES

To compare the efficacy of a newly available antiseptic solution (composed of 0.25% chlorhexidine gluconate, 0.025% benzalkonium chloride, and 4% benzyl alcohol), with 10% povidone iodine, on the prevention of central venous or arterial catheter colonization and infection.

DESIGN

Prospective, randomized clinical trial.

SETTING

Surgical-trauma intensive care unit (ICU) in a university hospital.

PATIENTS

All patients admitted to the ICU and requiring the insertion of a central venous and/or an arterial catheter from July 1, 1992 to October 31, 1993.

INTERVENTIONS

Patients were randomly assigned to one of two groups according to the antiseptic solution used for insertion and catheter care. The same solution was used for skin disinfection from the time of catheter insertion to the time of removal of each catheter.

MEASUREMENTS AND MAIN RESULTS

Catheter distal tips were quantitatively cultured when catheters were no longer necessary, if there was a suspicion of catheter-related infection, and routinely after 7 days of use for arterial catheters, or after 15 days of use for central venous catheters. The rate of significant catheter colonization (i.e., > or = 10(3) colony-forming units [cfu]/mL by quantitative culture), and catheter-related sepsis (as defined by sepsis abating following catheter removal per 1,000 catheter-days), were significantly lower in the chlorhexidine group (12 vs. 31 [relative risk 0.4, 95% confidence interval 0.1 to 0.9, p < .01] and 6 vs. 16 [relative risk 0.4, 95% confidence interval 0.1 to 1, p = 0.5], respectively). The rate of central venous catheter colonization and central venous catheter-related sepsis per 1,000 catheter-days were also significantly lower in the chlorhexidine group (8 vs. 31 [relative risk 0.3, 95% confidence interval 0.1 to 1, p = .03] and 5 vs. 19 [relative risk 0.3, 95% confidence interval 0.1 to 1, p = .02], respectively). Finally, the rate of arterial catheter colonization per 1,000 catheter-days was significantly lower in the chlorhexidine group (15 vs. 32 [relative risk 0.5, 95% confidence interval 0.1 to 1, p = .05]), whereas the rate of arterial catheter-related sepsis per 1,000 catheter-days was similar for the two study groups (8 in the chlorhexidine group vs. 10 in the povidone iodine group [relative risk 0.8, 95% confidence interval 0.1 to 2.2, p = .6]). The 0.25% chlorhexidine solution was superior to the 10% povidone iodine solution in preventing catheter colonizations and catheter-related sepsis due to Gram-positive bacteria (5 vs. 20 [p < .001], and 2 vs. 10 [p < .001], respectively), whereas the activity of the 0.25% chlorhexidine solution was nonsignificantly superior in preventing Gram-negative infections (7 vs. 4 [p = .5], and 4 vs. 2 [p = .8], respectively).

CONCLUSIONS

The 4% alcohol-based solution of 0.25% chlorhexidine gluconate and 0.025% benzalkonium chloride was more effective than 10% povidone iodine for insertion site care of short-term central venous and arterial catheters. This effect appeared related to a more efficacious prevention of infections with Gram-positive bacteria.

Reappraisal of Thomas Lewis's place in the history of electrocardiography

Thomas Lewis is among the most significant figures in the history of electrocardiography. In the late 1920s, he abandoned electrocardiography for other areas that he considered to be clinical science, in spite of the fact that he had made great contributions to the then new technique and that interest in this technique was increasing worldwide. The reasons why Lewis left electrocardiography are discussed further here. Lewis's leaving of electrocardiography had as much influence on the history of electrocardiography as did his practice of it.

Beta-globin gene haplotype in Hb SC disease

We asked the question, is the haplotype found with the sickle hemoglobin gene associated with different hematological characteristics in patients who were combined heterozygotes for sickle hemoglobin and hemoglobin C (Hb SC disease)? In 73 adults with Hb SC disease, a Benin haplotype chromosome was present in 56%, and Bantu (or Central African Republic; CAR), Senegal, and atypical haplotype chromosomes were found in 25%, 6%, and 12%, respectively. No significant difference were found in hematological characteristics or fetal hemoglobin levels of patients with Benin/C, CAR/C, Senegal/C, and atypical/C haplotypes. There were 71% C I, 18% C II, and 11% other beta(c) haplotypes. Fetal hemoglobin levels are lower in Hb SC disease than in sickle-cell anemia. Perhaps because haplotype has no discernible effect on fetal hemoglobin level in Hb SC disease, it does not modulate its hematological features.

Consecutive isolation of homologous strains of methicillin-resistant and methicillin-susceptible Staphylococcus aureus from a hospitalized child

A multiply resistant, methicillin-resistant Staphylococcus aureus was repeatedly isolated from the anterior nares of a premature neonate hospitalized in an intensive-care unit and treated with multiple courses of antibiotics. Two months following cessation of antibiotic therapy, a strain of S. aureus with a similar antibiotic resistance profile, but susceptible to methicillin, was isolated from three consecutive nasal swabs. Total DNA of the methicillin-susceptible and -resistant isolates was digested with SmaI and resolved by pulsed-field gel electrophoresis. The SmaI restriction profile of the susceptible isolate was similar to that of the resistant one except for the replacement of a 207-kb fragment by a 147-kb fragment. In Southern hybridization, a mecA-specific probe hybridized to the 207-kb SmaI fragment of the methicillin-resistant strain but not to DNA of the susceptible strain. These results suggest that loss of the mecA gene can occur in vivo when antibiotic selective pressure is removed.

Use of the coagulase gene typing method for detection of carriers of methicillin-resistant Staphylococcus aureus

Strains of Staphylococcus aureus can be typed on the basis of the polymorphism of the coagulase gene. DNA fragments generated after amplification by polymerase chain reaction (PCR) of the variable region of this gene and digested with the restriction enzyme HaeIII can be compared by their restriction fragment length polymorphism (RFLP). Seventy-nine of 86 (91.8%) methicillin-resistant S. aureus (MRSA) strains isolated in various hospitals had a characteristic RFLP pattern. This pattern differed from those of 32 methicillin-susceptible S. aureus (MSSA). Only one MSSA shared with MRSA the same RFLP pattern. After modification, we applied this method to the rapid detection of MRSA from 255 nasal swabs from patients hospitalized in intensive care units. When screened by plating on Chapman agar, 55 of these samples contained MRSA, whereas 40/55 yielded the expected restriction profile after amplification by PCR. No DNA was amplified by PCR in 9/55 samples and restriction profiles were uninterpretable in six cases. When compared to culture, the positive and negative predictive values of the PCR test were 100% and 93%, respectively. The specificity was 100% and the sensitivity was 72.7%. Since control of spread of MRSA strains in hospitals is based in part on rapid isolation of carriers, this method which allows detection of epidemic MRSA in nasal swabs within a day could be helpful, though culture would still be necessary to confirm the result.

Differential sensitivity of stilbenedisulfonates in their reaction with band 3 HT (Pro-868-->Leu)

Band 3 HT (Pro-868-->Leu) is a mutant anion exchange protein which has several phenotypic characteristics, including a 2- to 3-fold larger Vmax, and reduced covalent binding of the anion transport inhibitor 4,4'-diisothiocyanodihydrostilbene-2,2'-disulfonate (H2DIDS). We have used fluorescence kinetic methods to study inhibitor binding to band 3 to determine if the point mutation in band 3 HT produces localized or wide-spread conformational changes within the membrane-bound domain of this transporter. Our results show that covalent binding of H2DIDS by band 3 HT is slower by a factor of 10 to 20 compared with the wild-type protein. In contrast, no such difference in the kinetics was observed for covalent binding of 4,4'-diisothiocyanostilbene-2,2'-disulfonate (DIDS). In addition, the kinetics of H2DIDS release from band 3 HT was abnormal, while the kinetics of 4,4'-dibenzamidostilbene-2,2'-disulfonate (DBDS) release showed no difference when compared with the wild-type protein. We conclude that substitution of leucine for proline at position 868 does not perturb the structure of "lysine A" in the membrane-bound domain of band 3 but rather produces an apparently localized conformational change in the C-terminal subdomain of the protein which alters H2DIDS affinity. When combined with the observation of an increased Vmax, these results suggest that protein structural changes at position 868 influence a turnover step in the transport cycle.

Fulminating systemic capillary leak syndrome with lymphocytosis and hypogammaglobulinemia

We report a case of fulminating systemic capillary leak syndrome which temporarily responded to verapamil, a calcium channel blocker. We noted two features of the disease not previously reported: a rise in lymphocyte count 2-3 days prior to an attack, and hypogammaglobulinemia. These findings are discussed in relation to the possible etiology of this disease.

Appropriate place of death for cancer patients: views of general practitioners and hospital doctors

BACKGROUND

The majority of cancer patients in the United Kingdom die in a National Health Service hospital, a setting that is contrary to the wishes of those patients expressing a preference to die elsewhere, for example at home or in a hospice.

AIM

A study was undertaken to determine clinicians' views of the appropriate place of death for cancer patients and to examine factors leading to patients being admitted to a hospital specialist services unit where they died.

METHOD

A questionnaire was sent to all general practitioners and hospital doctors who had cared for cancer patients who had died between May 1991 and April 1992 in a single health district. The appropriateness of the place of death, whether the patient was terminally ill, reasons for hospital admission and effect on management had different resources been available were determined.

RESULTS

A total of 1022 deaths attributable to cancer were recorded for patients registered with general practitioners in the study area. Questionnaires were returned by general practitioners for 951 of the deaths (93%); hospital doctors returned questionnaires for 216 out of 268 patients (81%) who had been admitted to hospital under the care of a consultant. For deaths which had occurred at home, in a community hospital, residential/nursing home or Marie Curie hospice, the place of death was considered appropriate by general practitioners in over 92% of cases. For deaths in the hospital specialist services unit the place of death was considered probably or definitely appropriate by general practitioners in 83% of the 212 cases, but not appropriate in 17% of cases (P < 0.001 compared with all other settings). Hospital doctors considered 27% of deaths in the unit inappropriate. Significantly fewer cases fulfilled the criteria for terminal illness (death expected and palliative treatment commenced) according to general practitioners among those dying in the specialist services unit compared with deaths elsewhere (P < 0.001). The most common main reasons for admission to the specialist services unit were for investigation, because of difficult symptom control (apart from pain) and for curative/active treatment. General practitioners reported that management of between a sixth and a quarter of patients admitted to the specialist services unit would have been affected by the availability of 24-hour home cover, community hospital beds and a city-based hospice. Among the group of patients fulfilling the study criteria for terminal illness, the effect of other services on patient management would have been considerably higher.

CONCLUSION

A greater proportion of cases where patients died from cancer in settings other than a specialist services unit were considered appropriate by general practitioners compared with deaths in a specialist services unit. For a considerable minority of patients, death in a specialist services unit was not considered appropriate by the general practitioners or by the hospital doctors. Improvements in local hospice facilities, community hospitals and community support would mean that a substantial proportion of hospital admissions could be avoided and thus cancer patients could die in more appropriate settings.

Can Matrigel substitute for Vero cells in promoting the in-vitro development of mouse embryos?

The influences of Vero cells and the basement membrane substratum for these cells (Matrigel) on the rate of hatched blastocyst formation from mouse zygotes in vitro were compared. Zygotes obtained from C57BL/6 x BALB/c F1 females pretreated with pregnant mare's serum gonadotrophin/human chorionic gonadotrophin mated with BDF1 males were cultured (120 h) in human tubal fluid medium supplemented 0.5% with bovine serum albumin. The rates of early hatching and hatched blastocyst formation at 96 and 120 h of culture were expressed as the percentage of 2-cell embryos visualized after the initial 24 h. The rate of total blastocyst formation did not differ between treatment groups. However, < 10% of embryos cultured for 96 h in medium alone advanced to the hatching stage compared with 35-40% of blastocysts cultured with Vero cells or with Matrigel alone. Similarly, by 120 h of culture, only 20% of embryos cultured in medium alone developed to hatching or hatched blastocysts compared with > 70% for those embryos co-cultured with Vero cells or with Matrigel. In conclusion, Vero cells improved the rate of development of mouse embryos to hatched blastocysts during serum-free culture. Similar improvements were seen in the presence of Matrigel alone; Matrigel is the basement membrane substratum used for the Vero cells. Further studies on the means whereby Matrigel promotes early embryonic development (e.g. appropriate combination of basement membrane-associated growth factors) may lead to a safe, defined medium preparation for the stimulation of in-vitro development of human embryos.

Seronegative chronic relapsing neuroborreliosis

We report an unusual patient with evidence of Borrelia burgdorferi infection who experienced repeated neurologic relapses despite aggressive antibiotic therapy. Each course of therapy was associated with a Jarisch-Herxheimer-like reaction. Although the patient never had detectable free antibodies to B. burgdorferi in serum or spinal fluid, the CSF was positive on multiple occasions for complexed anti-B. burgdorferi antibodies, B. burgdorferi nucleic acids and free antigen.

Prediction of final height in short, normal and tall children

Measurements of final height were made on more than 4000 children in the final grade of school in Gothenburg in 1992; at the same time, mid-parental heights were recorded. These data were combined with other information (sex, length of gestation, size at birth, estimated age at peak height velocity (PHV) and height measurements made before 8 years of age) and used in a multiple regression analysis to assess the strength of the linear relationship between attained final height and these other potentially predictive measures of adult height. The R2 value increased from 0.16 at birth to 0.64 when the child was 8 years old. The inclusion of mid-parental height in the regression analysis contributed significantly to the explained variation in final height, especially at the earlier ages; the further addition of size at birth and age at PHV provides a small increase in the explained variation. The probability that the final height of a child will be below -2 or above +2 standard deviation scores (SDS) was assessed, based on previous SDS values for height when younger and on mid-parental height SDS. As a result of the large sample size included in the analyses, considerable confidence can be placed on the accurate prediction of final height values in the range -2.5 to +2.5 SDS.

Rate of activation and deactivation of K:Cl cotransport by changes in cell volume in hemoglobin SS, CC and AA red cells

Red blood cells (RBC) of subjects homozygous for hemoglobin A (AA), C (CC) and S (SS) exhibit different cell volumes which might be related to differences in cell volume regulation. We have investigated how rapidly K:Cl cotransport is activated and deactivated to regulate the cell volume in these cells. We measured the time course of net K+ efflux after step changes in cell volume and determined two delay times: one for activation by cell swelling and a second for deactivation by cell shrinkage. Cell swelling induced by 220 mOsm media activated K+ efflux to high values (10-20 mmol/liter cell x hr) in CC and SS; normal AA had a threefold lower activity. The delay time for activation was very short in blood with a high percentage of reticulocytes (retics): (SS, 10% retics, 1.7 +/- 0.3 min delay, n = 8; AA, 10% retics, 4 +/- 1.5 min, n = 3; CC, 11.6% retics, 4 +/- 0.3, n = 3) and long in cells with a smaller percentage of reticulocytes: (AA, 1.5% retics, 10 +/- 1.4 min, n = 8; CC whole blood 6% retics, 10 +/- 2.0 min, n = 10, P < 0.02 vs. SS). The delay times for deactivation by cell shrinking were very short in SS (3.6 +/- 0.4 min, n = 8, P < 0.02) and AA cells with high retics (2.7 +/- 1 min, n = 3) and normal retics (2.8 +/- 1 min, n = 3), but 8-15-fold longer in CC cells (29 +/- 2.8 min, n = 9). Density fractionation of CC cells (n = 3) resulted in coenrichment of the top fraction in reticulocytes and in swelling-activated cotransport (fourfold) with short delay time for activation (4 +/- 0.3 min) and long delay for deactivation (14 +/- 4 min). The delay time for activation, but not for deactivation, increased markedly with increasing cell density. These findings indicate that all CC cells do not promptly shut off cotransport with cell shrinkage and high rates of cellular K+ loss persist after return to isotonic conditions. In summary, (i) K:Cl cotransport is not only very active in young cells but it is also very rapidly activated and deactivated in young AA and SS cells by changes in cell volume. (ii) Delay times for cotransport activation markedly increased with RBC age and in mature cells with low cotransport rates, long delay times for activation were observed.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of aspirin and nonsteroidal antiinflammatory drug therapy on bleeding complications in dermatologic surgical patients

BACKGROUND

Aspirin and nonsteroidal antiinflammatory drugs (NSAIDs) inhibit platelet cyclooxygenase activity, resulting in altered platelet function and thus potentially enhanced bleeding.

OBJECTIVE

We examined the frequency of operative bleeding complications in dermatologic surgical patients taking these drugs and the value of template bleeding time estimates in predicting this complication.

METHODS

Bleeding time was measured with and without therapy in 23 patients and was correlated to bleeding complications after skin tumor or benign lesion excision in 40 patients taking aspirin, 21 taking NSAIDs, and 20 taking neither drug.

RESULTS

Bleeding time dropped significantly (p < 0.01) when patients stopped therapy for at least 5 days (median, 7 days), although bleeding time was prolonged in only 6 of 16 patients taking aspirin and 2 of 7 taking NSAID. In patients who continued antiplatelet drugs during surgery, bleeding time was prolonged in 8 of 40 patients taking aspirin and in 1 of 21 treated with NSAIDs. Excessive intraoperative bleeding occurred in three aspirin-treated patients, all of whom had a prolonged bleeding time, compared with none of those with normal bleeding times (p < 0.001, Fisher's exact probability test) and with none of those taking NSAIDs. Postoperative ooze requiring a dressing replacement occurred in one NSAID-treated patient and in three patients taking neither drug.

CONCLUSION

Bleeding time is increased by aspirin and NSAID therapy but is prolonged beyond the normal range in only approximately 25% of aspirin-treated and 10% of NSAID-treated patients. Intraoperative bleeding complications occurred only in patients receiving aspirin who had a prolonged bleeding time. Postoperative oozing occurred only in NSAID-treated and in untreated patients and thus is probably unrelated to antiplatelet therapy. Patients with a normal bleeding time can continue aspirin or NSAID therapy before dermatologic surgery.

Toward the unification of sequence and structural data for identification of structural and functional constraints

The identification and characterization of local residue patterns or conserved segments shared by a set of biopolymers has provided a number of insights in molecular biology. Biopolymer sequences are observations from macro molecules that share common structural or function features. The approach taken here rests on the notion that information may be most efficiently extracted from these observations through the use of a model that faithfully represents macro-molecular characteristics. Accordingly, our efforts are focused on statistical models which attempt to capture central features of protein structure, function, and change. Here the assumptions that underlie two new methods for the analysis of protein sequence data are explicitly delineated. (1) Threading of a sequence through structural motifs seeks to determine if a protein sequence fits a known protein structure. The assumptions delineated here also generally apply to other contact based threading methods that have been recently described. (2) Multiple sequence alignment via the Gibbs sampling algorithm seeks to identify position specific empirical free energy models for residue sites in common motifs and simultaneously the align sequence observations form these motifs.

The RAD6 DNA repair pathway in Saccharomyces cerevisiae: what does it do, and how does it do it?

The RAD6 pathway of budding yeast, Saccharomyces cerevisiae, is responsible for a substantial fraction of this organism's resistance to DNA damage, and also for induced mutagenesis. The pathway appears to incorporate two different recovery processes, both regulated by RAD6. The error-prone recovery process accounts for only a small amount of RAD6-dependent resistance, but probably all induced mutagenesis. The underlying mechanism for error-prone recovery is very likely to be translesion synthesis. The error-free recovery process accounts for most of RAD6-dependent resistance, but its mechanism is less clear; it may entail error-free bypass by template switching and/or DNA gap filling by recombination. RAD6 regulates these activities by ubiquitinating target proteins, but the identities of these target proteins, and the roles they play in error-free and error-prone recovery, have not yet been established.

The influence of general practitioner community hospitals on the place of death of cancer patients

All deaths from cancer were identified from death certificates in the Exeter Health District for a period of one year. Place of death, age, cancer type and access to general practitioner community hospital beds and the domiciliary hospice service were recorded. There were 1022 deaths attributable to cancer (parts 1a, 1b or 1c of the death certificate) who were patients of general practitioners in the health district. The place of death for patients with access to community hospital beds were: home 173/590 (29%), community hospital 232/590 (39%), specialist services unit 102/590 (17%), nursing or residential home 32/590 (5%), Marie Curie hospice 51/590 (9%). For patients without access to community hospital beds the place of death was: home 177/427 (41%), specialist service unit 165/427 (39%), nursing or residential home 42/427 (10%), Marie Curie hospice 43/427 (10%). The presence of community hospital beds was associated with a significant reduction of deaths in the specialist service unit (p < 0.001) and with a smaller reduction in home deaths (p < 0.01). Access to the domiciliary hospice services in areas with community beds was not associated with any significant change in the place of death. General practitioners cared for 74% of cases at the time of death in areas with access to community hospital beds and for 51% of cases without such access, which was a significant difference (p < 0.001). It therefore appears that community hospitals play a major role in the terminal care of cancer patients and access to such beds is associated with a decrease in cancer deaths occurring in specialist services beds.

Band 3 HT, a human red-cell variant associated with acanthocytosis and increased anion transport, carries the mutation Pro-868-->Leu in the membrane domain of band 3

1. We have studied band 3 HT, a human red-cell band 3 variant with increased M(r), which is associated with abnormal red-cell shape (acanthocytosis) and increased anion-transport activity. 2. We have shown that the increased M(r) does not result from the presence of the band 3 Memphis mutation, and that the variant band 3 is covalently labelled by 4,4'-di-isothiocyanato-1,2-diphenylethane-2,2'-disulphonic acid (H2DIDS) less readily than normal. 3. cDNA cloning studies show that band 3 HT results from the mutation Pro-868-->Leu, and the possible significance of the mutation in the altered anion-transport activity and cytoskeleton binding properties of band 3 HT is discussed.

The td intron endonuclease I-TevI makes extensive sequence-tolerant contacts across the minor groove of its DNA target

I-TevI, a double-strand DNA endonuclease encoded by the mobile td intron of phage T4, has specificity for the intronless td allele. Genetic and physical studies indicate that the enzyme makes extensive contacts with its DNA substrate over at least three helical turns and around the circumference of the helix. Remarkably, no single nucleotide within a 48 bp region encompassing this interaction domain is essential for cleavage. Although two subdomains (DI and DII) contain preferred sequences, a third domain (DIII), a primary region of contact with the enzyme, displays much lower sequence preference. While DII and DIII suffice for recognition and binding of I-TevI, all three domains are important for formation of a cleavage-competent complex. Mutational, footprinting and interference studies indicate predominant interactions of I-TevI across the minor groove and phosphate backbone of the DNA. Contacts appear not to be at the single nucleotide level; rather, redundant interactions and/or structural recognition are implied. These unusual properties provide a basis for understanding how I-TevI recognizes T-even phage DNA, which is heavily modified in the major groove. These recognition characteristics may increase the range of natural substrates available to the endonuclease, thereby extending the invasive potential of the mobile intron.

Anabolic steroid abuse and cardiac death

OBJECTIVE

To examine the relationship between anabolic steroid abuse and cardiac death. We report the first two cases in Australia. They are the only reported cases in which the anabolic steroid oxymesterone has been detected. This compound has never been approved for use in Australia.

CLINICAL FEATURES

Two footballers, aged 18 and 24, sustained fatal cardiac arrests while at training sessions. Both were considered fit and healthy.

OUTCOME

Autopsy revealed features of a hypertrophic cardiomyopathy in the 18-year-old; the 24-year-old had findings of a myocarditis. In both cases the coronary arteries were normal and there was no evidence of coronary thrombosis. Urine in both subjects contained the anabolic steroid oxymesterone.

CONCLUSIONS

There are limited clinical uses for anabolic steroids but they are widely abused by athletes in attempts to alter lean body mass and strength. Acute non-fatal myocardial infarction was first reported in 1988 and fatal myocardial infarction in 1990. While a causal relationship is hard to prove, it is possible that the anabolic steroid contributed to the increase in cardiac size in the first subject and may have increased his responsiveness to catecholamines causing an arrhythmogenic event. In the second, the inflammatory changes could have provided the focus for an arrhythmia. It would appear that anabolic steroid abuse should be considered in any athlete presenting with an acute vascular event.

Hematologic changes in massive burn injury

OBJECTIVE

To study and report the striking hematologic changes that occur in patients with massive burn injury.

DESIGN

Case reports and description of hematologic studies.

SETTING

A municipal general hospital burn unit.

PATIENTS

Three severely burned patients who survived, respectively, 45 mins, 22 hrs, and 57 hrs after hospitalization.

METHODS

Routine clinical hematologic laboratory studies.

RESULTS

The patients had intravascular hemolysis, and their RBCs exhibited spherocytosis, fragmentation, and vesiculation. Numerous fragments of red cell membranes were originally present in the blood and cleared within 4 hrs. These fragments may have contributed to the renal failure seen in these patients. The patients also had marked pseudothrombocytosis, presumably owing to "incorrect recognition" by the automatic counter of red cell microvesicles as platelets.

CONCLUSIONS

Pseudothrombocytosis should be anticipated with massive burn injury. Despite high or normal platelet counts reported by the laboratory, evidence of intravascular coagulation should be promptly investigated.

Teenagers and the risks of sexually transmitted diseases: a need for the provision of balanced information

OBJECTIVE

Evaluation of teenagers' knowledge and understanding about sexually transmitted disease, conception and contraception.

DESIGN

A questionnaire study.

SETTING

Schools

SUBJECTS

1025 teenagers aged 15/16 years (mean 16.00).

MAIN OUTCOME MEASURES

Scores attained in response to questions about sexually transmitted disease related to the sources of information given as most helpful.

RESULTS

Teenagers have an incorrect understanding of the risks of sexually transmitted diseases.

CONCLUSIONS

Teenagers may substantially underestimate their personal risk of contracting sexually transmitted diseases following the promotion of information about HIV/AIDS. Apparently simple messages about HIV and AIDS given in mass media advertising programmes may have unwanted results and need to be balanced by appropriate professional interpretation to teenagers.

Elliptocytosis associated with an abnormal alpha glycophorin

A case of elliptocytosis associated with an undescribed abnormal alpha glycophorin (alpha GP) is reported. Using immunoblotting techniques, a clear-cut minor band 6' was detected emerging just behind the monomer of delta GP (band 6) when probed with anti-alpha GP antiserum. It also reacted with anti-peptide C antiserum, suggesting that this new band with a molecular weight of 24 K is related to the structural alteration of alpha GP and not delta GP. The erythrocyte membrane proteins of the patient exhibited a quite normal pattern, with a normal alpha spectrin/beta spectrin ratio, but the reaction with anti-protein 4.1 serum confirmed the increase in proteolytic susceptibility of her protein 4.1. The results of DNA mapping implied that the abnormality may be due to a short deletion of the heterozygote. The significance of deviation involving the alpha GP and protein 4.1 to the elliptocytic change of erythrocyte shape is briefly discussed.

The effect of indomethacin on anthralin inflammation

The effect of prostaglandin inhibition, using topical indomethacin, on anthralin inflammation was studied. Indomethacin gel and gel base were applied to opposite flexor forearm skin sites of 11 volunteers for 2 h and then washed off. Anthralin and UVB were then applied to the gel-treated skin and the anthralin- and UVB-induced erythema and oedema were measured at 2, 6, 24 and 48 h using Harpenden callipers and a reflectance erythrometer. Prostaglandin inhibition was demonstrated by a significant reduction of UVB erythema at the indomethacin-treated sites compared to the gel-base-treated sites. There was a small but significant reduction in anthralin erythema, but not oedema, at the indomethacin-treated sites compared to the gel-base sites. This study demonstrates that prostaglandins, and other inflammatory mediators because the inhibitory effect was small, are involved in anthralin inflammation.

Quantitative PCR with internal controls

We examine the use of internal controls for estimating the expected initial copy number of the target in a polymerase chain reaction (PCR). We base our investigation on an extended branching-process model. In terms of that model, we delineate the necessary assumptions for this methodology to yield approximately unbiased answers, and we provide means for testing some of those assumptions. We show how to design a series of PCRs to attain optimal precision of the estimate. We provide an algorithm for conducting the statistical analysis of the data, including a formula for a confidence interval for the unknown expected initial copy number.

Clinical methods of goniometry: a comparative study

This investigation compared the reliability and interchangeable use of three currently available goniometers--a universal goniometer, a fluid goniometer, and an electrogoniometer. Three consecutive readings of the active range of movement of the right elbow joint were taken from each of 23 healthy female volunteers; three experienced observers each used each type of goniometer on two occasions. A balanced experimental design was used to eliminate order effects with respect to subject, tester, or goniometer, and a rigid protocol was employed to reduce error due to diurnal or methodological variations. The results show that there are significant differences between the goniometers used, the testers, and the replications. Significant interaction effects also exist between the goniometers and the occasion, the goniometers and the testers, and the testers and replications. The data suggest that the interchangeable use of different types of goniometer in a clinical setting is inadvisable.

Polycythemia vera: dental management considerations

This article presents a case of dental treatment in a patient with polycythemia vera. Polycythemia vera is an uncommon myeloproliferative disease that can have hematologic and surgical implications. The concerns and consequences of dental care in these patients are discussed and recommendations for dental treatment are given.

The unique red cell heterogeneity of SC disease: crystal formation, dense reticulocytes, and unusual morphology

Knowledge concerning SS (homozygous for the beta s gene) red blood cell (RBC) heterogeneity has been useful for understanding the pathophysiology of sickle cell anemia. No equivalent information exists for RBCs of the compound heterozygote for the beta s and beta c genes (SC) RBCs. These RBCs are known to be denser than most cells in normal blood and even most cells in SS blood (Fabry et al, J Clin Invest 70:1284, 1981). We have analyzed the characteristics of SC RBC heterogeneity and find that: (1) SC cells exhibit unusual morphologic features, particularly the tendency for membrane "folding" (multifolded, unifolded, and triangular shapes are all common); (2) SC RBCs containing crystals and some containing round hemoglobin (Hb) aggregates (billiard-ball cells) are detectable in circulating SC blood; (3) in contrast to normal reticulocytes, which are found mainly in a low-density RBC fraction, SC reticulocytes are found in the densest SC RBC fraction; and (4) both deoxygenation and replacement of extracellular Cl- by NO3- (both inhibitors of K:Cl cotransport) led to moderate depopulation of the dense fraction and a dramatic shift of the reticulocytes to lower density fractions. We conclude that the RBC heterogeneity of SC disease is very different from that of SS disease. The major contributions of properties introduced by HbC are "folded" RBCs, intracellular crystal formation in circulating SC cells, and apparently a very active K:Cl cotransporter that leads to unusually dense reticulocytes.

A gene deleted in Kallmann's syndrome shares homology with neural cell adhesion and axonal path-finding molecules

Kallmann's syndrome (clinically characterized by hypogonadotropic hypogonadism and inability to smell) is caused by a defect in the migration of olfactory neurons, and neurons producing hypothalamic gonadotropin-releasing hormone. A gene has now been isolated from the critical region on Xp22.3 to which the syndrome locus has been assigned: this gene escapes X inactivation, has a homologue on the Y chromosome, and shows an unusual pattern of conservation across species. The predicted protein has significant similarities with proteins involved in neural cell adhesion and axonal pathfinding, as well as with protein kinases and phosphatases, which suggests that this gene could have a specific role in neuronal migration.

Metastatic tumor: the complementary role of the marrow aspirate and biopsy

To determine whether bone marrow aspiration or biopsy is more sensitive in the detection of nonhematologic metastatic involvement of marrow, all 1569 consecutive paired biopsy and aspirate samples obtained between January 1975 and January 1, 1986 in an 800 bed municipal hospital were reviewed. At least eight aspirate slides and 10 biopsy cross sections were examined for each pair. In 39 samples, both biopsy and aspirate identified metastatic tumor. No biopsies contained tumor that was not also seen on the aspirate. However, five aspirate slides contained metastatic malignancies not identified on biopsy. The hematologist or oncologist viewing individual cells in a monolayer at 1000 x magnification has the advantage of identifying very small clusters of tumor cells. That accounted for three of the five positive aspirate samples in which the biopsies were negative. The other two positive aspirate slides each contained tumor on only one of eight slides. The results of our study indicate that when carefully reviewed, the aspirate is at least as sensitive as the marrow biopsy for identifying metastatic tumor. Our results indicate that marrow aspirates and biopsies are useful and complementary examinations for identifying metastatic malignancy.

Low to moderate maternal alcohol use before and during pregnancy, and neurobehavioural outcome in the newborn infant

Of 2002 randomly selected pregnant women recruited prospectively over a three-year period for an extensive questionnaire survey, a stratified subsample of 665 mothers was selected for mother-infant follow-up on the basis of pre-pregnancy alcohol intake. Infant outcome was assessed by detailed clinical examination and application of a modified Einstein Neonatal Behavioural Assessment Schedule (ENBAS) performed at 24 to 72 hours of age. Of the infant responses to 25 ENBAS items, only tonus showed a small but significant relationship to pre-pregnancy maternal alcohol intake. The authors conclude that low to moderate maternal alcohol intake has no significant effect on newborn neurological status.

An update of the Swedish reference standards for weight, length and head circumference at birth for given gestational age (1977-1981)

An update of the Swedish reference standards for weight, length, and head circumference at birth, for each week of gestational age, is presented. It is based on the total Swedish cohorts of infants born 1977-1981 (n = 475,588). A "healthy population" (79%) was extracted, using prospectively collected data. Weekly (28-42 weeks) grouped data for length and head circumference were well approximated by the normal distribution, but the distributions for birthweight were positively skewed. The original skewed distributions for birthweight were transformed, using the square root, resulting in distributions close to the Gaussian. For smoothing purposes, the weakly values for the mean and the standard deviation were both fitted by a third degree polynomial function. These functions also make possible the calculation of the continuous variable, standard deviation score, for individual newborn infants as well as a comparison of distributions between groups of infants. The reference values and charts presented here have two major advantages over the current Swedish ones: the sample size used is now sufficiently large at the lower gestational ages, so that empirically found variations can be used, and the skewness of the birth weight distribution has been taken into account. The use of the reference standards presented here improves and facilitates evaluation of size deviation at birth.

The distinct pathobiology of sickle cell-hemoglobin C disease. Therapeutic implications

The data available clearly establish that the hyperconcentration of hemoglobin C and S inside SC cells is the main and driving mechanism for the pathologic behavior of these cells. It facilitates the polymerization of Hb S, but it also favors the tendency of Hb C to induce the formation of crystals and aggregates, abnormal morphologic shapes, and abnormally dense reticulocytes, through a particularly active K:Cl cotransport. Why these cells are endowed with a particularly active K:Cl cotransport is still a mystery; it is disproportionate with the extent of the hemolysis and the number of young cells. Is there an abnormal interaction between Hb C and the K:Cl cotransport protein in the inner aspect of the membrane? Are there abnormal interactions between Hb C and the other transport mechanisms that balance the shrinking capacity of K:Cl cotransport (as Na/H exchange)? Only future work will tell. In any case, SC disease is unique among the hemoglobinopathies in that a single intervention could correct all abnormalities: the restitution of the normal MCHC, as proven experimentally by Fabry et al. Hence, effort should be centered on looking for compounds that increase red cell volume, because in SC cells, increases in volume will not distort the cell, but restore it to the normal red cell volume and the normal red cell shape. This luxury is not available for cells with normal MCHC (the majority of the red cells in SS blood), because increasing their volume will progressively turn them into spheres, a rheologically disadvantaged shape.

Characterization of a murine gene expressed from the inactive X chromosome

In mammals, equal dosage of gene products encoded by the X chromosome in male and female cells is achieved by X inactivation. Although X-chromosome inactivation represents the most extensive example known of long range cis gene regulation, the mechanism by which thousands of genes on only one of a pair of identical chromosomes are turned off is poorly understood. We have recently identified a human gene (XIST) exclusively expressed from the inactive X chromosome. Here we report the isolation and characterization of its murine homologue (Xist) which localizes to the mouse X inactivation centre region and is the first murine gene found to be expressed from the inactive X chromosome. Nucleotide sequence analysis indicates that Xist may be associated with a protein product. The similar map positions and expression patterns for Xist in mouse and man suggest that this gene may have a role in X inactivation.