Associations of the skin, oral and gut microbiome with aging, frailty and infection risk reservoirs in older adults

Older adults represent a vulnerable population with elevated risk for numerous morbidities. To explore the association of the microbiome with aging and age-related susceptibilities including frailty and infectious disease risk, we conducted a longitudinal study of the skin, oral, and gut microbiota in 47 community- or skilled nursing facility-dwelling older adults vs. younger adults. We found that microbiome changes were not associated with chronological age so much as frailty: we identified prominent changes in microbiome features associated with susceptibility to pathogen colonization and disease risk, including diversity, stability, heterogeneity, and biogeographic determinism, which were moreover associated with a loss of Cutibacterium (C.) acnes in the skin microbiome. Strikingly, the skin microbiota were also the primary reservoir for antimicrobial resistance, clinically important pathobionts, and nosocomial strains, suggesting a potential role particularly for the skin microbiome in disease risk and dissemination of multidrug resistant pathogens.

1206. Association of Aging, Frailty and Place of Residence with Skin, Oral and Gut Microbiome Characteristics and Pathogenicity Reservoirs

Background

Despite their elevated risk for morbidity and mortality from infections, the microbiota of older adults remain understudied. While colonization resistance from resident microflora is a promising means to prevent infections, little is known about pathogenicity reservoirs and colonization resistance in this vulnerable population. Here we study the skin, oral, and gut microbiome dynamics of older adults in both community and Skilled Nursing Facility (SNF) settings, investigating relationships between age, frailty, environment, microbiota, and pathogenicity reservoirs.

Methods

We conducted a longitudinal metagenome survey of 47 adults age 65+ years of age; 22 residents of 3 different SNFs and 25 community dwelling individuals. We performed metagenomic whole genome shotgun sequencing on stool, oral, and skin samples from 8 sites, 1421 total. To correlate clinical and behavioral variables, we measured frailty, collected medical records, and interviewed participants on diet and lifestyle. We also draw comparisons with previous younger cohorts.

Results

• Compared to younger adults, the skin microbiota of older adults was characterized by

◦ High heterogeneity

◦ Decreased stability over time, suggesting increased susceptibility to colonization and pathogenicity

◦ Compositional differences including significantly lower levels of Cutibacterium acnes, with reciprocal increases in Staphylococci, Corynebacteria, and Malassezia

• In older adults, Frailty (Rockwood) was found to have linear correlation with relative abundance of species relevant to infection risk including acnes, staphylococci, streptococci, E. coli, Akkermansia mucinophila, and Enterococcus faecalis.

• The skin, oral, and gut microbiota of SNF residents had substantially elevated virulence factor and antibiotic resistance genes.

Conclusion

To the best of our knowledge, this is largest report to date of the skin metagenome in older adults. We demonstrate distinct and significant differences between cohorts with clinically relevant implications. We believe these results may inform infection control and prevention by increasing our understanding of colonization resistance and pathogenicity reservoirs, as well as advance our knowledge of the relationship between aging, the microbiome, and infections.

Disclosures

All Authors: No reported disclosures

Host-Specific Evolutionary and Transmission Dynamics Shape the Functional Diversification of Staphylococcus epidermidis in Human Skin

Metagenomic inferences of bacterial strain diversity and infectious disease transmission studies largely assume a dominant, within-individual haplotype. We hypothesize that within-individual bacterial population diversity is critical for homeostasis of a healthy microbiome and infection risk. We characterized the evolutionary trajectory and functional distribution of Staphylococcus epidermidis-a keystone skin microbe and opportunistic pathogen. Analyzing 1,482 S. epidermidis genomes from 5 healthy individuals, we found that skin S. epidermidis isolates coalesce into multiple founder lineages rather than a single colonizer. Transmission events, natural selection, and pervasive horizontal gene transfer result in population admixture within skin sites and dissemination of antibiotic resistance genes within-individual. We provide experimental evidence for how admixture can modulate virulence and metabolism. Leveraging data on the contextual microbiome, we assess how interspecies interactions can shape genetic diversity and mobile gene elements. Our study provides insights into how within-individual evolution of human skin microbes shapes their functional diversification.

Isolation and Characterization of Mouse Coagulation Factor X – Biophysical and Enzymological Properties

Mouse factor X was highly purified from plasma using barium ion precipitation and chromatography on anion-exchange and heparin- agarose affinity chromatography columns. Intact and reduced patterns of mouse factor X in SDS-PAGE were similar to those of human factor X. The specific absorption E 1%/1 cm at 280 nm of mouse factor X was found to be 11.2. Content of carbohydrate moieties of mouse factor X, determined to be 10% by weight, differs both quantitatively and quantitatively from that of human factor X, while the γ-carboxy- glutamic acid (Gla) and β-hydroxy-aspartic acid (β-OH-Asp) content were essentially the same as for human factor X. The amino-terminal amino acid sequences of the light and heavy chains of mouse factor X separated by SDS-PAGE were ANSFF--FKK and SVALXTSDSE, respectively. Underlined residues are non-identical with those of human factor X. Clotting time-based assays using human factor X- deficient plasma as substrate exhibited the following apparent extents of activation of factor X in mouse plasma, using human plasma as the standard: 195% (intrinsic); 200% (extrinsic); and 190% (RVV-X). Using the purified proteins in the same assay systems, the following apparent activation of mouse factor X was demonstrated, compared with human factor X: 195% (intrinsic); 27% (extrinsic); and 41% (RVV-X). These activity profiles suggest that the human extrinsic coagulation pathway functions less efficiently than the corresponding mouse pathway in the activation of mouse factor X. Furthermore, mouse brain thromboplastin satisfactorily replaced rabbit brain thromboplastin in extrinsic activation of factor X in mouse plasma, but not of human plasma or purified mouse or human factor X, in line with studies by others suggesting that human factor Vila poorly activates factor X in the presence of mouse tissue factor. While fully RVV-X-activated mouse factor X activated human prothrombin at a rate equal to about 117% of that for human factor X, it hydrolyzed the synthetic substrate, S-2222, at a rate of only about 18% of that for human factor X. These results are expected to be useful in making the mouse suitable for study of the mammalian blood coagulation pathways.

Full-length sucrose-formulated recombinant factor VIII for treatment of previously untreated or minimally treated young children with severe haemophilia A

The safety and efficacy of a full-length sucrose-formulated recombinant factor VIII product (rFVIII-FS; KogenateFS; Kogenate Bayer) was evaluated in previously untreated (PUPs) and minimally treated (MTP) patients with severe haemophilia A (FVIII < 2%). Patients (37 PUPs; 24 MTPs) aged 0.1–25.7 months were treated with rFVIII-FS for a cumulative of 9,141 exposure days (EDs), median 114 EDs (range 4–478), on prophylactic or on-demand therapy. Eighty-nine percent of all treated bleeding episodes were successfully treated with 1 (74%) or 2 (15%) infusions. Clinical response to first infusion for each bleeding episode was rated as ‘excellent’ in 58%, or ‘good’ in 33%, of all cases. Recombinant FVIII-FS was used in 27 surgical procedures, mainly catheter implantations, which were all conducted without bleeding complications. FVIII recovery mean values (~2%/kg/ IU) were as expected for any licensed FVIII concentrate. FVIII neutralizing antibody formation was 15% (9/60). Aside from inhibitor formation, three adverse events were rated as ‘at least possibly drug-related’ for a total drug-related adverse event rate of 0.14%. No viral seroconversions were observed. Overall, excellent safety and efficacy were demonstrated with rFVIII-FS for therapy of young children with severe haemophilia A.

Individual and Combined Effects of Peroxisome Proliferator-Activated Receptor α and γ Agonists, Fenofibrate and Rosiglitazone, on Biomarkers of Lipid and Glucose Metabolism in Healthy Nondiabetic Volunteers

This open-label, randomized, placebo-controlled, incomplete-block, 3-period crossover pilot study investigated the effects of peroxisome proliferator-activated receptor alpha- and gamma-agonists on biomarkers of lipid and glucose metabolism in 12 nondiabetic subjects. Plasma samples were collected before and after each 14-day treatment with placebo, fenofibrate (201 mg/d), rosiglitazone (4 mg twice daily), and combined fenofibrate (201 mg/d) plus rosiglitazone (4 mg twice daily). Except for triglycerides (P < .042) and free fatty acids (P < .074), no significant interaction was demonstrated between fenofibrate and rosiglitazone; thus, the effect due to each drug alone was evaluated (presence/absence of drug). Fenofibrate significantly (P < .050) increased lipoprotein lipase activity (35%) and decreased apolipoproteins B (13%) and C-III (20%). Rosiglitazone significantly (P < .050) decreased fasting glucose (7.3%) and increased apolipoprotein C-III (19%) and adiponectin (137%). Fenofibrate and rosiglitazone also produced effects on triglycerides and free fatty acids, but it was not possible to determine if these effects were synergistic in nature.

Role of the gamma-carboxyglutamic acid domain of activated factor X in the presence of calcium during inhibition by antithrombin-heparin

BACKGROUND

Factor (F)Xa has 11 gamma-carboxylated glutamic acid (Gla) residues that are involved in calcium-dependent membrane binding. The serpin antithrombin (AT) is an important physiological regulator of FXa activity in an inhibition reaction that is enhanced by heparin. Recently, Rezaie showed that calcium further enhanced the heparin-catalyzed AT inhibition of FXa by promoting 'ternary complex' formation, and these results showed a role for the gamma-carboxyl-glutamate (Gla)-domain of FXa.

OBJECTIVES

In this study, we used recombinant FXa mutants to assess the role of individual Gla residues in augmenting or antagonizing the AT-heparin inhibition reaction in the presence of calcium.

RESULTS AND CONCLUSIONS

In the absence of heparin, AT inhibition of plasma and the recombinant FXas were essentially equivalent. Similar to plasma-derived FXa, calcium increased about 3-fold the inhibition rate of wild-type recombinant FXa by AT-heparin over that in the presence of EDTA. Interestingly, three different effects were found with the recombinant FXa Gla-mutants for AT-heparin inhibition: (i) Gla-->Asp 14 and 29 were enhanced without calcium; (ii) Gla-->Asp 16 and 26 were not enhanced by calcium; and (iii) Gla-->Asp 19 was essentially the same as wild-type recombinant FXa. These results support a theory that mutating individual Gla residues in FXa alters the calcium-induced conformational changes in the Gla region and affects the antithrombin-heparin inhibition reaction.

Modelling haemophilia epidemiology and treatment modalities to estimate the unconstrained factor VIII demand

The article presents a new method for estimating the unconstrained factor VIII (FVIII) demand based on the principles of decision analysis. Epidemiology and treatment modalities were integrated into a model for unconstrained FVIII demand. Assumptions for each variable with impact on the unconstrained FVIII demand were defined and probability estimates for these variables were obtained from the literature and medical experts. The sensitivity of the unconstrained FVIII demand to each of the variables was determined, and the variables with the greatest impact were modelled probabilistically. The probability-weighted average for the unconstrained FVIII demand model was 6.9 units per capita with a 90% uncertainty interval of 2.7-13.6 units per capita. When compared with FVIII usage in countries, only Luxembourg's use of FVIII (7.7 units per capita) exceeded the probability-weighted average for the modelled unconstrained FVIII demand. As better information becomes available, revision of model variables is easily accomplished allowing for a more accurate and dynamic forecast of demand over time. More accurate modelling of the 'true' demand longitudinally should help prevent shortages of FVIII concentrates such as those that have occurred in the past. In addition, a more accurate forecast of FVIII demand will allow national health care policy makers to better allocate financial and other resources. Sufficient and consistent supply of FVIII concentrates and appropriate financing of haemophilia care will allow the clinical benefits of more aggressive treatment regimens such as prophylaxis to be realized.

AAV-mediated factor IX gene transfer to skeletal muscle in patients with severe hemophilia B

Hemophilia B is an X-linked coagulopathy caused by absence of functional coagulation factor IX (F.IX). Previously, we established an experimental basis for gene transfer as a method of treating the disease in mice and hemophilic dogs through intramuscular injection of a recombinant adeno-associated viral (rAAV) vector expressing F.IX. In this study we investigated the safety of this approach in patients with hemophilia B. In an open-label dose-escalation study, adult men with severe hemophilia B (F.IX < 1%) due to a missense mutation were injected at multiple intramuscular sites with an rAAV vector. At doses ranging from 2 x 10(11) vector genomes (vg)/kg to 1.8 x 10(12) vg/kg, there was no evidence of local or systemic toxicity up to 40 months after injection. Muscle biopsies of injection sites performed 2 to 10 months after vector administration confirmed gene transfer as evidenced by Southern blot and transgene expression as evidenced by immunohistochemical staining. Pre-existing high-titer antibodies to AAV did not prevent gene transfer or expression. Despite strong evidence for gene transfer and expression, circulating levels of F.IX were in all cases less than 2% and most were less than 1%. Although more extensive transduction of muscle fibers will be required to develop a therapy that reliably raises circulating levels to more than 1% in all subjects, these results of the first parenteral administration of rAAV demonstrate that administration of AAV vector by the intramuscular route is safe at the doses tested and effects gene transfer and expression in humans in a manner similar to that seen in animals.

Manufacturing challenges in the commercial production of recombinant coagulation factor VIII

Advances in gene technology have led to the development of a method to manufacture recombinant coagulation Factor VIII (rFVIII) for haemophilia A. Because rFVIII is a large and complex protein, its commercialization has required that many challenges in manufacturing, purification and processing be overcome. In order to license the first generation of rFVIII (Kogenate) in 1993, Bayer Corporation invested over 10 years in research and manufacturing development. Seven additional years were subsequently devoted to research and manufacturing improvements in order to accomplish the recent licensing of a second rFVIII product (KOGENATE Bayer or Kogenate FS). This product differs from its predecessor, in that human albumin is removed from the purification and the formulation steps. In addition, fewer chromatography steps are involved resulting in greater yields per mL of conditioned medium, and a solvent-detergent viral inactivation step replaces the heat-processing step used for the previous product. Despite these changes in the manufacturing, the protein backbone and carbohydrate structure of the final rFVIII molecule are identical. The complexity of the production processes is reflected by over 100 000 manufacturing data entries and by 600 quality control tests for each batch of rFVIII. Manufacturers are continuing to develop the next generation of rFVIII, which will be produced without the addition of any human or animal proteins or byproducts. Investments in research, development and manufacturing technology are expected to result in the development of new products with enhanced safety profiles, and in an increase in the production capacity for products that are chronically in short supply.

Posttranslational modifications of recombinant myotube-synthesized human factor IX

Recent data demonstrate that the introduction into skeletal muscle of an adeno-associated viral (AAV) vector expressing blood coagulation factor IX (F.IX) can result in long-term expression of the transgene product and amelioration of the bleeding diathesis in animals with hemophilia B. These data suggest that biologically active F.IX can be synthesized in skeletal muscle. Factor IX undergoes extensive posttranslational modifications in the liver, the normal site of synthesis. In addition to affecting specific activity, these posttranslational modifications can also affect recovery, half-life in the circulation, and the immunogenicity of the protein. Before initiating a human trial of an AAV-mediated, muscle-directed approach for treating hemophilia B, a detailed biochemical analysis of F.IX synthesized in skeletal muscle was carried out. As a model system, human myotubes transduced with an AAV vector expressing F.IX was used. F.IX was purified from conditioned medium using a novel strategy designed to purify material representative of all species of rF.IX in the medium. Purified F.IX was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), N-terminal sequence analysis, chemical gamma-carboxyglutamyl analysis, carbohydrate analysis, assays for tyrosine sulfation, and serine phosphorylation, and for specific activity. Results show that myotube-synthesized F.IX has specific activity similar to that of liver-synthesized F.IX. Posttranslational modifications critical for specific activity, including removal of the signal sequence and propeptide, and gamma-carboxylation of the N-terminal glutamic acid residues, are also similar, but carbohydrate analysis and assessment of tyrosine sulfation and serine phosphorylation disclose differences. In vivo experiments in mice showed that these differences affect recovery but not half-life of muscle-synthesized F.IX.

Effect of rofecoxib on the pharmacokinetics of digoxin in healthy volunteers

The authors examined the effect of the cyclooxygenase-2 (COX-2) inhibitor, rofecoxib, at steady state on the pharmacokinetics of digoxin following a single dose in healthy subjects. Each healthy subject (N = 10) received rofecoxib (75 mg once daily) or placebo for 11 days in a double-blind, randomized, balanced, two-period crossover study. A single 0.5 mg oral dose of digoxin elixir was administered on the 7th day of each 11-day period. Each treatment period was separated by 14 to 21 days. Samples for plasma and urine immunoreactive digoxin concentrations were collected through 120 hours following the digoxin dose. No statistically significant differences between treatment groups were observed for any of the calculated digoxin pharmacokinetic parameters. For digoxin AUC(0-infinity), AUC(0-24), and Cmax, the geometric mean ratios (90% confidence interval) for (rofecoxib + digoxin/placebo + digoxin) were 1.04 (0.94, 1.14), 1.02 (0.94, 1.09), and 1.00 (0.91, 1.10), respectively. The digoxin median tmax was 0.5 hours for both treatments. The harmonic mean elimination half-life was 45.7 and 43.4 hours for rofecoxib + digoxin and placebo + digoxin treatments, respectively. Digoxin is eliminated renally. The mean (SD) cumulative urinary excretion of immunoreactive digoxin after concurrent treatment with rofecoxib or placebo was 228.2 (+/- 30.8) and 235.1 (+/- 39.1) micrograms/120 hours, respectively. Transient and minor adverse events occurred with similar frequency on placebo and rofecoxib treatments, and no treatment-related pattern was apparent. Rofecoxib did not influence the plasma pharmacokinetics or renal elimination of a single oral dose of digoxin.

The effect of rofecoxib on the pharmacodynamics and pharmcokinetics of warfarin

OBJECTIVE

The objective of this study was to examine the effect of 3 doses of rofecoxib (12.5, 25, and 50 mg) on the pharmacodynamics and pharmacokinetics of warfarin.

METHODS

Two single-dose (12.5 or 50 mg of rofecoxib with 25 mg or 30 mg of oral warfarin, respectively, on day 7 of each period) trials (N = 12 men) and 1 steady-state warfarin trial (25 mg rofecoxib; N = 15, 13 men and 2 women) were completed as two-period, randomized, balanced, crossover, double-blind designs. The prothrombin time international normalized ratio (INR) and S(-) and R(+) warfarin enantiomers were assessed during 144 hours after the single warfarin doses. In the steady-state warfarin trial, after the attainment of a stable INR (1.4-1.7), the stable warfarin dose was co-administered with rofecoxib (25 mg) and placebo over two 21-day periods. After the dose of warfarin on day 21, INR and S(-) and R(+) warfarin were assessed during 24 hours.

RESULTS

Compared with placebo, rofecoxib slightly increased the INR by approximately 5% (90% confidence interval on the geometric ratio, 1.03, 1.08) and 11% (1.04, 1.19) for the two single-dose warfarin trials with 12.5 and 50 mg of rofecoxib, respectively. In the steady-state warfarin study with 25 mg of rofecoxib, the INR was increased by 8% (1.02, 1.15). Rofecoxib had no significant effect (versus placebo) on the pharmacokinetics of S(-) warfarin. However, in the 3 studies, treatment with 12.5, 25, and 50 mg of rofecoxib was associated with a 27%, 38%, and 40% increase in the area under the plasma concentration-time curve of the biologically less active R(+) warfarin.

CONCLUSIONS

Rofecoxib increased plasma concentrations of the biologically less active R(+) warfarin, which accounted for a small increase in INR. The approximately 8% increase in INR at steady state with warfarin co-administered with 25 mg of rofecoxib is not likely to be clinically important in most patients taking warfarin. However, standard monitoring of INR values should be conducted when therapy with rofecoxib is initiated or changed, particularly in the first few days, for patients receiving warfarin.

Enhanced gamma-carboxylation of recombinant factor X using a chimeric construct containing the prothrombin propeptide

Factor Xa is the serine protease component of prothrombinase, the enzymatic complex responsible for thrombin generation. Production of recombinant factor X/Xa has proven to be difficult because of inefficient gamma-carboxylation, a critical post-translational modification. The affinities of the vitamin K-dependent propeptides for the gamma-carboxylase vary over 2 logs, with the propeptide of factor X having the highest affinity followed by the propeptides of factor VII, protein S, factor IX, protein C, and prothrombin [Stanley, T. B. (1999) J. Biol. Chem. 274, 16940-16944]. On the basis of this observation, it was hypothesized that exchanging the propeptide of factor X with one that binds the gamma-carboxylase with a reduced affinity would enhance gamma-carboxylation by allowing greater substrate turnover. A chimeric cDNA consisting of the human prothrombin signal sequence and propeptide followed by mature human factor X was generated and stably transfected into HEK 293 cells, and modified factor X was purified from conditioned medium. The results indicate that on average 85% of the total factor X produced with the prothrombin propeptide was fully gamma-carboxylated, representing a substantial improvement over a system that employs the native factor X propeptide, with which on average only 32% of the protein is fully gamma-carboxylated. These results indicate that the affinity of the gamma-carboxylase for the propeptide greatly influences the extent of gamma-carboxylation. It was also observed that regardless of which propeptide sequence is directing gamma-carboxylation (factor X or prothrombin), two pools of factor X are secreted; one is uncarboxylated and a second is fully gamma-carboxylated, supporting the notion that the gamma-carboxylase is a processive enzyme.

Effect of cyclooxygenase-2 inhibition on renal function in elderly persons receiving a low-salt diet. A randomized, controlled trial

BACKGROUND

Most nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit both cyclooxygenase-1 (COX-1), whose inhibition is associated with gastrointestinal ulceration, and COX-2, whose inhibition is associated with therapeutic benefits. Although agents that do not produce COX-1 activity may have fewer adverse effects, targeted disruption of the COX-2 allele in mice has resulted in severe renal problems, suggesting that COX-2 inhibition may also produce adverse effects.

OBJECTIVE

To determine the effect of rofecoxib, a member of the coxib class of drugs and a specific inhibitor of the COX-2 enzyme, on renal function in elderly patients.

DESIGN

A randomized, three-period, single-dose crossover study and a randomized, parallel-group, multiple-dose study.

SETTING

Clinical research units.

PATIENTS

75 patients 60 to 80 years of age.

INTERVENTION

In the first study, single doses of rofecoxib, 250 mg (about 5-fold to 20-fold the recommended dose); indomethacin, 75 mg; and placebo were administered to 15 patients. In the second study, multiple doses of rofecoxib, 12.5 or 25 mg/d; indomethacin, 50 mg three times daily; or placebo were administered to 60 patients. Patients in both studies received a low-sodium diet

MEASUREMENTS

Glomerular filtration rate, creatinine clearance, and urinary and serum sodium and potassium values.

RESULTS

Compared with placebo, single doses of rofecoxib and indomethacin decreased the glomerular filtration rate by 0.23 m/s (P < 0.001) and 0.18 mL/s (P = 0.003), respectively. In contrast, respective decreases of 0.14, 0.13, and 0.10 mL/s were observed after multiple doses of rofecoxib, 12.5 mg/d (P = 0.019); rofecoxib, 25 mg (P = 0.029), and indomethacin (P = 0.086) were administered. Changes in creatinine clearance and serum and urinary sodium and potassium were less pronounced.

CONCLUSIONS

The effects of COX-2 inhibition on renal function are similar to those observed with nonselective NSAIDs. Thus, COX-2 seems to play an important role in human renal function.

Evidence for gene transfer and expression of factor IX in haemophilia B patients treated with an AAV vector

Pre-clinical studies in mice and haemophilic dogs have shown that introduction of an adeno-associated viral (AAV) vector encoding blood coagulation factor IX (FIX) into skeletal muscle results in sustained expression of F.IX at levels sufficient to correct the haemophilic phenotype. On the basis of these data and additional pre-clinical studies demonstrating an absence of vector-related toxicity, we initiated a clinical study of intramuscular injection of an AAV vector expressing human F.IX in adults with severe haemophilia B. The study has a dose-escalation design, and all patients have now been enrolled in the initial dose cohort (2 x 10(11) vg/kg). Assessment in the first three patients of safety and gene transfer and expression show no evidence of germline transmission of vector sequences or formation of inhibitory antibodies against F.IX. We found that the vector sequences are present in muscle by PCR and Southern-blot analyses of muscle biopsies and we demonstrated expression of F.IX by immunohistochemistry. We observed modest changes in clinical endpoints including circulating levels of F.IX and frequency of FIX protein infusion. The evidence of gene expression at low doses of vector suggests that dose calculations based on animal data may have overestimated the amount of vector required to achieve therapeutic levels in humans, and that the approach offers the possibility of converting severe haemophilia B to a milder form of the disease.

Acute effect of ephedrine on 24-h energy balance

Ephedrine is used to help achieve weight control. Data on its true efficacy and mechanisms in altering energy balance in human subjects are limited. We aimed to determine the acute effect of ephedrine on 24-h energy expenditure, mechanical work and urinary catecholamines in a double-blind, randomized, placebo-controlled, two-period crossover study. Ten healthy volunteers were given ephedrine (50 mg) or placebo thrice daily during each of two 24-h periods (ephedrine and placebo) in a whole-room indirect calorimeter, which accurately measures minute-by-minute energy expenditure and mechanical work. Measurements were taken of 24-h energy expenditure, mechanical work, urinary catecholamines and binding of (+/-)ephedrine in vitro to human beta1-, beta2- and beta3-adrenoreceptors. Twenty-four-hour energy expenditure was 3.6% greater (8965+/-1301 versus 8648+/-1347 kJ, P<0.05) with ephedrine than with placebo, but mechanical work was not different between the ephedrine and placebo periods. Noradrenaline excretion was lower with ephedrine (0.032+/-0.011 microg/mg creatinine) compared with placebo (0.044+/-0.012 microg/mg creatinine) (P<0.05). (+/-)Ephedrine is a relatively weak partial agonist of human beta1- and beta2-adrenoreceptors, and had no detectable activity at human beta3-adrenoreceptors. Ephedrine (50 mg thrice daily) modestly increases energy expenditure in normal human subjects. A lack of binding of ephedrine to beta3-adrenoreceptors and the observed decrease in urinary noradrenaline during ephedrine treatment suggest that the thermogenic effect of ephedrine results from direct beta1-/beta2-adrenoreceptor agonism. An indirect beta3-adrenergic effect through the release of noradrenaline seems unlikely as urinary noradrenaline decreased significantly with ephedrine.

The PRO-SELF Mouth Aware program: an effective approach for reducing chemotherapy-induced mucositis

Many oncology patients receive chemotherapy drugs that have the potential to induce oral mucositis. If mucositis is not prevented, patients will have to manage the problems associated with mucositis: pain, local infection, and decreased ability to take fluids or food. At the time of this writing, clinical approaches for mucositis management are variable and generally ineffective. The mouth care program, PRO-SELF: Mouth Aware (PSMA), presented in this article, was found to be a significant component of a self-care program that may have reduced the incidence of chemotherapy-induced mucositis. The PSMA program has three dimensions: (a) didactic information, (b) development of self-care exercises (skills), and (c) supportive interactions with a nurse in the setting where the patients are receiving their treatment. This program focuses on decreasing the direct (i.e., incidence and severity of mucositis) and indirect morbidities of oral mucositis (i.e., number of local infections, level of discomfort/pain, and disruption in fluid and/or food intake). It provides the critical dimensions (i.e., specific information, self-care exercises, and nurse support) to promote the prevention of mucositis. The PSMA program is designed to provide patients with a definitive self-care repertoire to manage chemotherapy-induced mucositis in the home without the direct supervision of a health care provider.

Structure/function analyses of recombinant variants of human factor Xa: factor Xa incorporation into prothrombinase on the thrombin-activated platelet surface is not mimicked by synthetic phospholipid vesicles

This report describes the expression, purification, and characterization of a series of recombinant factor Xa variants bearing aspartate substitutions for each of the glutamate residues which normally undergo gamma-carboxylation. Factor X was expressed in human embryonic kidney cells and purified from conditioned media by immunoaffinity and hydroxylapatite chromatography. Factor X was activated with Russell's viper venom factor X activator, and single-chain unactivated factor X was removed from activated factor X by size-exclusion chromatography. Recombinant wild-type factor Xa had normal activity in a clotting assay, and mutants with aspartate substitutions for glas residues 16, 26, and 29 had no detectable clotting activity. In purified component assays, these gla variants had essentially no detectable activity in the prothrombinase complex assembled on synthetic phospholipid vesicles but had significant activity when the prothrombinase was assembled on thrombin-activated platelets. In addition, the gla 32 variant had normal activity in the platelet prothrombinase but diminished activity in prothrombinase assembled on synthetic PSPC vesicles. These differences were not accounted for by the total phospholipid composition of the thrombin-activated platelet membrane. We have produced fully active recombinant human factor Xa and demonstrated that gla residues 16, 26, and 29 are critical for normal activity of factor Xa. More importantly, this study provides an extensive characterization of macromolecular enzyme complex formation with gla variants of a vitamin K-dependent coagulation protein and provides evidence that prothrombinase complex assembly on thrombin-activated platelets is not equivalent to assembly on synthetic phospholipid vesicles. The data suggest that thrombin-activated platelets possess some element(s) (other than 30% phosphatidyl serine or factor Va), presumably either protein or phospholipid, that serves as a component of the factor Xa binding site.

Tissue factor regulates plasminogen binding and activation

Tissue factor (TF) has been implicated in several important biologic processes, including fibrin formation, atherogenesis, angiogenesis, and tumor cell migration. In that plasminogen activators have been implicated in the same processes, the potential for interactions between TF and the plasminogen activator system was examined. Plasminogen was found to bind directly to the extracellular domain of TF apoprotein (amino acids 1-219) as determined by optical biosensor interaction analysis. A fragment of plasminogen containing kringles 1 through 3 also bound to TF apoprotein, whereas isolated kringle 4 and miniplasminogen did not. Expression of TF on the surface of a stably transfected Chinese hamster ovary (CHO) cell line stimulated plasminogen binding to the cells by 70% more than to control cells. Plasminogen bound to a site on the TF apoprotein that appears to be distinct from the binding site for factors VII and VIIa as judged by a combination of biosensor and cell assays. TF enhanced two-chain urokinase (tcuPA) activation of Glu-plasminogen, but not of miniplasminogen, in a dose-dependent, saturable manner (half maximal stimulation at 59 pmol/L). TF apoprotein induced an effect similar to that of relipidated TF, but a relatively higher concentration of the apoprotein was required (half maximal stimulation at 3.8 nmol/L). The stimulatory effect of TF on plasminogen activation was confirmed when plasmin formation was examined directly on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In accord with this, TF inhibited fibrinolysis by approximately 74% at a concentration of 14 nmol/L and almost totally inhibited the binding of equimolar concentrations of plasminogen to human umbilical vein endothelial cells and human trophoblasts. Further, CHO cells expressing TF inhibited uPA-mediated fibrinolysis relative to a wild-type control. TF apoprotein and plasminogen were found to colocalize in atherosclerotic plaque. These data suggest that plasminogen localization and activation may be modulated at extravascular sites through a high-affinity interaction between kringles 1 through 3 of plasminogen and the extracellular domain of TF.

A symptom-management program for patients undergoing cancer treatment: the Pro-Self Program

OBJECTIVE

To describe the development, implementation, and refinement of the Pro-Self Program, a self-care intervention used in randomized clinical trials. The program is designed to provide adult patients undergoing cancer treatment with the information, skill, and support needed to engage effectively and consistently in prescribed self-care symptom management. The aim of the program is to enhance patients' self-care abilities to prevent symptoms or to reduce symptom severity and duration associated with disease and treatment. The program is based on work involving self-care during treatment for cancer.

METHODS

Patients were provided the program at the initiation of chemotherapy or radiation therapy and followed to the completion of treatment.

CONCLUSION

The program made an important contribution in teaching these patients self-care during the cancer treatment experience.

Isolation and characterization of mouse coagulation factor X -- biophysical and enzymological properties

Mouse factor X was highly purified from plasma using barium ion precipitation and chromatography on anion-exchange and heparin-agarose affinity chromatography columns. Intact and reduced patterns of mouse factor X in SDS-PAGE were similar to those of human factor X. The specific absorption E 1%/1 cm at 280 nm of mouse factor X was found to be 11.2. Content of carbohydrate moieties of mouse factor X, determined to be 10% by weight, differs both quantitatively and quantitatively from that of human factor X, while the gamma-carboxyglutamic acid (Gla) and beta-hydroxy-aspartic acid (beta-OH-Asp) content were essentially the same as for human factor X. The amino-terminal amino acid sequences of the light and heavy chains of mouse factor X separated by SDS-PAGE were ANSFF--FKK and SVALXTSDSE, respectively. Underlined residues are non-identical with those of human factor X. Clotting time-based assays using human factor X-deficient plasma as substrate exhibited the following apparent extents of activation of factor X in mouse plasma, using human plasma as the standard: 195% (intrinsic); 200% (extrinsic); and 190% (RVV-X). Using the purified proteins in the same assay systems, the following apparent activation of mouse factor X was demonstrated, compared with human factorX: 195% (intrinsic); 27% (extrinsic); and 41% (RVV-X). These activity profiles suggest that the human extrinsic coagulation pathway functions less efficiently than the corresponding mouse pathway in the activation of mouse factor X. Furthermore, mouse brain thromboplastin satisfactorily replaced rabbit brain thromboplastin in extrinsic activation of factor X in mouse plasma, but not of human plasma or purified mouse or human factor X, in line with studies by others suggesting that human factor VIIa poorly activates factor X in the presence of mouse tissue factor. While fully RVV-X-activated mouse factor X activated human prothrombin at a rate equal to about 117% of that for human factor X, it hydrolyzed the synthetic substrate, S-2222, at a rate of only about 18% of that for human factor X. These results are expected to be useful in making the mouse suitable for study of the mammalian blood coagulation pathways.

The presurgical management with erythrocytapheresis of a patient with a high-oxygen-affinity, unstable Hb variant (Hb Bryn Mawr)

BACKGROUND

Hemoglobin (Hb) Bryn Mawr is an unstable Hb variant resulting in congenital hemolytic anemia. This variant Hb also has an increased affinity for oxygen. The perioperative transfusion management of this disorder is described, and the first genomic analysis of this Hb variant is given.

CASE REPORT

An 11-year-old boy, heterozygous for Hb Bryn Mawr, was referred for cholecystectomy. Sequence analysis of genomic DNA confirmed that the patients was heterozygous for a T-->C transition in the codon for amino acid 85, causing a substitution of serine for phenylalanine in the beta-globin chain. On the basis of whole-blood O2 dissociation studies, projected tissue O2 delivery would have been suboptimal during general anesthesia; therefore, a partial red cell exchange transfusion was performed to lower variant Hb and prevent tissue hypoxia during surgery. The red cell mass to be exchanged (50%) was determined from the calculated increase in O2 delivery capacity required to maintain an O2 extraction of 4 to 5 mL of O2 per dL of whole blood. The p50 of whole blood from the patients immediately after the exchange transfusion was 16.0 torr. At the time of surgery, the p50 was normal (25.9 torr). The patient's whole blood 2,3 DPG levels were 4.70 mmol per mL of red cells (before transfusion) (normal range = 4.8 +/- 0.3 mmol/mL red cells), 4.07 mmol per mL of red cells (immediately after transfusion), and 4.55 mmol per mL of red cells (48 hours after transfusion).

CONCLUSION

This patient with Hb Bryn Mawr was prepared for surgery with a partial exchange transfusion to prevent tissue hypoxia during anesthesia. Decreased 2,3 DPG levels immediately after transfusion resulted in increased O2 affinity of whole blood; however, 48 hours after exchange transfusion, a normal p50 (due to both removal of variant Hb and regeneration of 2,3, DPG) was observed. Partial exchange transfusion is useful in the preoperative management of patients with Hb variants characterized by increased O2 affinity.

Antibodies to low-incidence antigens and elimination of the antihuman globulin phase of the crossmatch-case report: anti-Wra

An antibody to a low-incidence antigen was identified in the serum of a nontransfused male patient. The antibody was subsequently identified as anti-Wra and was only detectable at the antihuman globulin (AHG) phase of the crossmatch. Instances of severe hemolytic transfusion reactions have been reported following the transfusion of red blood cells containing low-incidence antigens in patients with antibodies directed toward these antigens (e.g., anti- Wra, -Cob, -Jsa, etc.). Elimination of the AHG phase of the crossmatch can result in either risks or benefits. Since patients seen at this facility primarily have been multitransfused or are multiparous females, the AHG phase of the crossmatch has been maintained.

Delayed hemolytic transfusion reaction due to anti-Go(a), an antibody against the low-prevalence Gonzales antigen

Go(a) (D(Cor)) is a low-frequency antigen in the Rh system found on red cells lacking part of the D mosaic (category IVa). Anti-Go(a) has not been previously reported to cause hemolytic transfusion reactions. A 27-year-old African American male with sickle-cell disease, maintained on chronic transfusion, was noted to have dark plasma during an erythrocytapheresis, procedure, and the pretransfusion hemoglobin was noted to be 1 g/dl lower than 4 weeks before (with hyperbilirubinemia and a significantly increased LDH). Polyspecific direct antiglobulin test (DAT) was weakly positive (C3-weak, IgG-weak), and indirect antiglobulin tests (IATs) performed on the serum (pre- and posttransfusion reaction) and a red blood cell (RBC) eluate from the postreaction sample were negative. A segment from one of the four implicated units from the prior month's transfusion was strongly reactive at 37 degrees C and using anti-human globulin (AHG) when crossmatched with the postreaction serum and the eluate. The postreaction serum, screened with a panel of red cells positive for low-prevalence antigens, reacted with three Go(a+) cells. The implicated unit was reactive with a previously identified anti-Go(a) serum.

Alloimmunization to platelets in heavily transfused patients with sickle cell disease

Bone marrow transplantation (BMT) is now an option for some patients with sickle cell disease (SCD). Many SCD patients are multiply transfused with red blood cells (RBCs), and may be immunized to alloantigens other than erythrocyte antigens. Because platelet refractoriness is a significant complication during BMT, we wished to determine the prevalence of alloimmunization to platelets in transfused SCD patients. Sera collected from 47 transfused and 14 untransfused SCD patients were screened for HLA and platelet-specific antibodies. Transfusion and RBC antibody histories were reviewed. A subset of the patients were rescreened 1 year later. Eighty-five percent of patients with at least 50 RBC transfusions (22 of 26), 48% of patients with less than 50 transfusions (10 of 21), and none of 14 untransfused patients demonstrated platelet alloimmunization (P < .05). Platelet alloimmunization was more prevalent than RBC alloimmunization (20% to 30%). Half of the platelet reactivity was chloroquine-elutable. Eighteen of 22 patients (82%) on chronic RBC transfusion remained platelet-alloimmunized 11 to 22 months after initial testing. In summary, 85% of heavily transfused SCD patients are alloimmunized to HLA and/or platelet-specific antigens. These patients may be refractory to platelet transfusion, a condition that would increase their risk during BMT. Leukodepletion in the transfusion support of SCD patients should be considered to prevent platelet alloimmunization.

Randomized clinical trial of chlorhexidine versus placebo for prevention of oral mucositis in patients receiving chemotherapy

PURPOSE/OBJECTIVES

To test the effectiveness of a nurse-initiated systematic oral hygiene teaching program-PRO-SELF: Mouth Aware (PSMA)-in conjunction with two mouthwashes (0.12% chlorhexidine or sterile water) in preventing chemotherapy-induced oral mucositis.

DESIGN

Randomized, double-blind, placebo-controlled, clinical trial.

SETTINGS

23 outpatient clinics and office practices in California.

SAMPLE

222 patients who were starting a cycle of mucositis-inducing chemotherapy.

METHOD

Participants were followed over three chemotherapy cycles. All patients were provided the PSMA program. Random assignment to a mouthwash occurred prior to the development of oral mucositis. Researchers used the Oral Assessment Guide to assess the patients oral cavities monthly (with the patients cycles of chemotherapy) and when patients reported any oral changes between cycles.

MAIN RESEARCH VARIABLES

Type of mouthwash, incidence, days to onset, and severity of chemotherapy-induced oral mucositis.

FINDINGS

No significant differences existed between the two mouthwashes in regard to incidence, days to onset, and severity of mucositis.

CONCLUSIONS

Because chlorhexidine (S20 per pint) was no more effective than water, a substantial cost savings can be realized by rinsing with water. Interestingly, the PSMA program appeared to reduce the incidence of mucositis from on a prior estimate of 44% to less than 26%.

IMPLICATIONS FOR NURSING PRACTICE

A nursing prescription of a systematic oral hygiene program using water as a mouth rinse is cost efficient and may be effective in preventing oral mucositis.

Differences in nausea, vomiting, and retching between younger and older outpatients receiving cancer chemotherapy

The purpose of this study was to determine whether there were differences in the side effects of nausea, vomiting, and retching (N, V, and R) between younger ( < 65 years, n = 102) and older ( > or = 65 years, n = 25) persons receiving outpatient chemotherapy. A longitudinal 4-month study was used for the 127 participants recruited from 18 settings. Participants completed two questionnaires (Inventory of N, V, and R and Behavior Checklist) over the course of the study. The pattern between the younger and older patients' N, V, and R subscale scores was consistent in that the younger patients' scores were consistently (except on one occasion) higher than the older patients' scores, but this difference was statistically insignificant. This study furthers our understanding of N, V, and R and has several clinical implications.

Structural integrity of the gamma-carboxyglutamic acid domain of human blood coagulation factor IXa Is required for its binding to cofactor VIIIa

This report describes the analysis of a novel mutant human factor IX protein from a patient with hemophilia B (factor IX activity <1%; factor IX antigen 45%). Enzymatic amplification of all eight exons of the factor IX gene followed by direct sequence analysis reveals a single nucleotide change (a guanine --> adenine transition) in exon 2 at nucleotide 6409 which results in a glycine --> arginine substitution at amino acid 12 in the gamma-carboxyglutamic acid rich (Gla) domain of the mature protein. Factor IX was isolated by immunoaffinity chromatography from plasma obtained from the proband. The purified protein is indistinguishable from normal factor IX by polyacrylamide gel electrophoresis. Characterization of the variant in purified component assays reveals that it is activated normally by its physiologic activator factor XIa, but its phospholipid-dependent activation by the factor VIIa-tissue factor complex is diminished. In the presence of phospholipid and 5 mM Ca2+, the activities of variant and normal plasma-derived factor IX are similar; however, in the presence of activated factor VIIIa (intrinsic tenase complex), the normal augmentation of the cleavage of the specific substrate of factor IX, factor X, is not observed. The determination of the association constants for normal and variant factor IXa with factor VIIIa shows that the affinity of the activated variant factor IX for the cofactor factor VIIIa is 172-fold lower than normal. Competition studies using active site-inactivated factor IXas in the intrinsic tenase complex confirm that the defect in the variant protein is in its binding to factor VIIIa. We conclude that the structural integrity of the Gla domain of human factor IX is critical for the normal binding of factor IXa to factor VIIIa in the intrinsic tenase complex. In addition, a glycine at amino acid 12 is necessary for normal activation of factor IX by the factor VIIa-tissue factor complex.

Perceptions of the needs of hospitalized patients undergoing bone marrow transplant

The purpose of this study was to determine patients' (N = 30) needs during the first 4 weeks after bone marrow transplant. These needs were identified during interviews using constant comparative analysis. The first week focused on a team effort toward cure; the second week emphasized symptom management; the third week stressed the work of getting better; and by the fourth week, there was concern about recovery and going home. Patients identified themselves, along with nurses, family, and physicians, as being responsible for meeting these needs. They viewed nurses as being responsible for carrying out the medical orders, managing symptoms, and keeping things in order. Patients wanted their family to be supportive emotionally and attend to their nonmedical needs and physicians to be responsible for the planning and monitoring of their medical care and to verify that satisfactory progress was occurring. For themselves, patients needed to maintain a positive attitude and be involved in their recovery.

The monocyte monolayer assay: a noninvasive technique for predicting the severity of in utero hemolysis

To test the noninvasive monocyte monolayer assay in predicting hemolytic severity in utero, we studied 18 patients from two institutions with significant erythrocyte alloantibodies. Serum samples were obtained from each patient. Each subject donated a serum sample during her pregnancy. Monocytes were harvested from a single healthy donor and grown in monolayer culture. Erythrocytes with the appropriate antigens were sensitized with maternal serum and incubated with the monocyte monolayers. Erythrophagocytosis was scored as a percentage of the positive control. Perinatal outcomes were assessed post hoc and cases were classified as unaffected or mildly, moderately, or severely affected using standard definitions. Prenatal management was conducted without knowledge of the results. Six of the 18 patients had severe disease and one of the 18 had moderately severe disease. At a cutoff level of 20, the assay generated the following results: sensitivity was 7 of 7 (100%), specificity was 10 of 11 (90.9%), positive predictive value was 7 of 8 (87.5%), and negative predictive value was 10 of 10 (100%). The monocyte monolayer assay appears to be a useful, noninvasive modality for predicting the severity of hemolytic disease in utero.

Comorbidity, nutritional intake, social support, weight, and functional status over time in older cancer patients receiving radiotherapy

It is essential that nurses gain insight about the responses of older adults to standard anticancer therapies because there is ongoing concern about whether the elderly are affected adversely by the prescribed therapy. The purpose of this longitudinal prospective study was to describe selected outcomes and their relationships in a sample of 45 elderly (mean age 69.8 years; range 61-86) patients receiving radiotherapy for either breast (42%) or lung (58%) cancer. The outcome variables were weight and multidimensional functional status; moderator variables were co-morbidity, nutritional intake, estimated adequacy of intake, radiation dose, side effects, and social support. Data were collected at the beginning of radiation (T1), the middle of therapy (T2), the conclusion of therapy (T3), and three months post radiation (T4). Although 81.4% had some concurrent condition, those with a comorbid condition did not respond significantly differently from those without a comorbid condition on any of the major variables at any of the four times. At none of the four times was the caloric intake adequate to meet the estimated energy requirements for usual activity (range 67.9-71.5%). However, caloric intake was not significantly related to weight at any of the four times. There was a significant weight decrease from beginning of therapy to the middle of therapy and from the beginning of therapy to conclusion of therapy. The percentage of calories contributed by protein was significantly correlated with weight during radiotherapy, and protein calories consumed at the previous time were correlated with weight at T2 and T3. In contrast, the percentage of calories contributed by carbohydrate intake was significantly negatively correlated with two of the four functional status measures at each time, but was not related to weight. In addition carbohydrate calories consumed at the previous time also were related to one or more functional status measures at succeeding time points. Almost no relationships were found between social support and the outcome measures of weight and functional status. Scores on three of the four functional status measures suggest improvement over time from initiation of radiation to 3 months after therapy. Scores on the fourth measure, Overall Health Rating, suggest a slight decline; however, the average score reflects good overall health. These findings provide evidence that this group of elderly, the great majority of whom had at least one comorbid condition, tolerated the course of radiation with less than adequate intake for usual activity, a slight decrease in mean weight, but without major disruptions in functional status.(ABSTRACT TRUNCATED AT 400 WORDS)

Influence of age on problems experienced by patients with lung cancer undergoing radiation therapy

The purpose of this prospective, longitudinal study was to determine if patients with lung cancer who are 65 years of age or older experience problems differently than do patients younger than age 65 during and following radiation treatment. The moderator and outcome variables selected for study were recognized attendant problems that may develop during lung cancer treatment and that may influence the treatment regimen and response. No statistically significant differences were found between patients age 65 or older and those younger than age 65 on caloric intake, adequacy of energy intake, total radiation dose, concurrent illnesses, and social support at any of four data-collection periods. Similarly, there were no significant differences on weight, body mass index, and multidimensional functional status. The relationship between the social support subscales and functional status measures for the 65-or-older group suggested that those subjects with lower social support perceived themselves to have better functional status. There was no relationship between social support and two functional status measures for the under-65 group. The significant relationships between social support and the overall health rating were in opposite directions for the two age groups. The results suggest that chronologic age alone may not be a sufficient criterion to determine therapeutic regimen or to suggest that unique problems may result.

Comparison of perceived symptoms of patients undergoing bone marrow transplant and the nurses caring for them

This study describes the symptomatology of patients hospitalized for bone marrow transplant (BMT) (n = 30) and compares their perceptions of these symptoms to those of nurses (n = 28). Patients and nurses responded to the Symptom Distress Scale (SDS) four times: within 48 hours of BMT day one (T1); day 7-10 post-BMT (T2); day 20-23 post-BMT (T3); and day 30-34 post-BMT (T4). Patients also completed the Profile of Mood States at T1. Each time, the investigators completed a Karnofsky Performance Status evaluation of each patient. Patients perceived significantly more distress from their symptoms at T1 than their nurses perceived that they were experiencing. Over time, patients' SDS scores did not change significantly. However, nurses' SDS scores indicated significant differences, with their SDS scores at T1 less than those at T2 and T3. The results indicate the importance of nurses exploring the perceived symptom experiences of patients undergoing BMT. Any incongruence between nurses' and patients' perceptions potentially could prevent patients' symptoms from being managed effectively.

Comfort. Immigrant Hispanic cancer patients' views

This study focuses on the meaning of comfort from the perspective of immigrant Hispanic cancer patients undergoing treatment at a large Western medical center. Patients (n = 10), in 30 ethnographical interviews conducted in Spanish by a culturally sensitive interviewer identified characteristics, needs, and sources of comfort. The characteristics of comfort were: feeling integrated, functioning and normalcy, care and nurturing, security and safety, control and "comodo." Comfort needs evolved into 6 categories: nurturing, familiar environment, safety, quality of life, normalcy, and "animo." Providers of comfort, as perceived by these Hispanic patients were: self, family, health care providers, and God. The characteristics of comfort most frequently talked about by the Hispanic participants were feeling integrated and nurtured. Integrated, a seemingly complex characteristic of comfort, reflected a sense of inner peace with oneself that went beyond the physical comfort. Function and normalcy were also perceived to be important aspects of comfort. It is important to note that the Hispanic patients on occasion used culturally relevant terms, such as comodo and animo (neither of which are readily translated into English) to convey their impressions of comfort. The study demonstrates that comfort is important in illness and cancer treatment situations, and that for these Hispanic patients it also had influence from their culture.

Biology of inherited coagulopathies: factor IX

Characterization of the functional domains of FIX and related vitamin K-dependent proteins has been enhanced by the isolation and characterization of the genes encoding these proteins. A better understanding of the interactions between FIX's activators, cofactors, and substrate, FX, has been gained through the study of naturally occurring variants isolated from patients with hemophilia B and genetically engineered recombinant molecules. With the determination of specific mutations in hemophilia B kindreds, and through advances in molecular techniques, especially the polymerase chain reaction, more accurate determination of carrier status and prenatal diagnosis can now be made.

The relationship of visual acuity, tactile sensitivity, and mobility of the upper extremities to proficient breast self-examination in women 65 and older

The purpose of this study was to describe the relationship of visual acuity, tactile sensitivity, and mobility of the upper extremities to the performance of proficient breast self-examination (BSE) in women 65 and older. A convenience sample of 32 women, ages 66-89, met with the investigator to have their visual acuity, tactile sensitivity, and upper extremity mobility tested. Their ability to perform the visual, tactile, and upper extremity components of proficient BSE also was tested by using simulated breast models (SBMs). Thirty of the women had adequate visual acuity (< or = 20/40 Snellen equivalent) but were unable to visually detect the abnormalities on the SBM. Thirty of the women had tactile sensitivity of 10 mm (1 cm) or better on the static two-point discrimination test of the second, third, and fourth digits of each hand. Yet, only 13 of these women were able to locate the 1 cm lump; only 12 were able to locate the 5 mm lumps; and none were able to locate the 3 mm lump. The subjects' ability to pass the upper extremity mobility component of proficient BSE was significantly related to their ability to pass the upper extremity range of motion criteria. Limitations and deficits, mostly of the hands and shoulders, were revealed. When teaching BSE to older women, nurses are responsible for assessing limitations and deficits in their ability to perform proficient BSE and, if necessary, for intervening with alternatives. The need for further research in this area is indicated to improve assessment and education of older women regarding the use of proficient BSE for early detection of breast cancer.

Theory development in a non-university service setting

What is the role of the non-university service setting in theory development research? The authors discuss the importance of nursing theory to professional survival, economic necessity, and the generation of a knowledge base for practice. Motivational and contextual characteristics of the non-university setting that enhance or inhibit the conduct of research are identified. Common problems that arise from differing needs and goals of clinical nursing personnel and theoretical researchers are explicated. Specific strategies to facilitate theoretical research in a service setting are proposed.