The role of aspirin, statins, colchicine, and IL-1 inhibitors in prevention of cardiovascular events: a systematic integrative review

CONTEXT

Cardiovascular disease (CVD) is the leading cause of death in the United States. As such, an unmet need exists in the primary and secondary prevention of adverse cardiovascular events (CVEs). Specifically, identifying drugs that can reduce the progression of CVD and serious adverse events is much needed. Drugs that work by reducing platelet aggregation, blocking cholesterol formation (3-hydroxy-3-methyl-glutaryl-coenzyme A [HMG-CoA] reductase inhibitors), and/or blocking inflammation pathways (mainly interleukin-1b [IL-1b]) have been linked to preventing adverse CVEs, including acetylsalicylic acid (ASA, aspirin), statins, colchicine, and IL-1 inhibitors (interleukin-1 receptor antagonists). This systematic review aims to provide insight into utilizing these four agents for the primary and/or secondary prevention of CVD.

OBJECTIVES

In this systematic review, we opted to review the efficacy of aspirin, statins, colchicine, and IL-1 inhibitors in the primary and secondary prevention of CVE to provide clinical practitioners with evidence-based practice approaches and determine any unmet needs in their utilization.

METHODS

Between October 1 and 12, 2021, a search was conducted and completed on five databases: PubMed, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Web of Science, and Biomedical Reference Collection: Comprehensive. A total of 13 researchers (V.A., A.H., S.B., V.G., D.C., C.C., C.B., C.A., S.K., J.H., A.K., S.F., and S.E.) were involved in the search and screening of the articles. Search terms included "aspirin, statins, colchicine, IL-1 inhibitors, and primary, secondary, myocardial infarction (MI)." Inclusion criteria included clinical study design, English language articles, all genders older than 50 years old, and established patient history of CVD, including MI. In addition, articles were excluded if they were animal models, in vitro studies, pharmacokinetic studies, systematic reviews, literature reviews, and studies exploring therapies other than those listed in the inclusion criteria. First, five individuals independently sorted through abstracts or articles based on the inclusion and exclusion criteria. Then, a team of 13 individuals sorted through full-text articles of selected abstracts based on the same criteria. A separate researcher resolved conflicts between the team.

RESULTS

A total of 725 articles were identified from all databases, from which 256 duplicated articles were removed. Thus, a total of 469 articles abstracts were screened, of which 425 articles either did not meet the inclusion criteria or met the exclusion criteria. A total of 42 articles were retrieved and assessed for full-text review, from which 15 articles were retrieved for analysis.

CONCLUSIONS

Statins may prevent primary CVEs based on their role in preventing cholesterol formation. Aspirin, canakinumab, and colchicine may be helpful in the secondary prevention of CVEs due to their blocking of various steps in the inflammation pathway leading to CVD. Future research should primarily focus on the use of canakinumab and colchicine in preventing CVD due to the limited number of studies on these drugs.

Access to novel cancer medicines in four countries in Central and Eastern Europe in relation to clinical benefit

BACKGROUND

Almost 100 novel cancer medicines have been approved in Europe over the last decade. Limited public health care resources in countries in Central and Eastern Europe (CEE) call for a prioritization of access to effective medicines. We investigated how both reimbursement status and waiting time to reimbursement correlate with the magnitude of clinical benefit provided by novel medicines in four selected countries (Czechia, Hungary, Poland, and Slovakia).

MATERIALS AND METHODS

A total of 124 indications of 51 cancer medicines with marketing authorization by the European Medicines Agency in 2011-2020 were included and followed up until 2022. Data on reimbursement status and waiting time to reimbursement (i.e. time from marketing authorization to national reimbursement approval) were collected for each country. Data were analyzed in relation to clinical benefit status (i.e. substantial versus nonsubstantial clinical benefit) of indications according to the European Society for Medical Oncology Magnitude of Clinical Benefit Scale (ESMO-MCBS).

RESULTS

The degree of reimbursement differed between countries with 64% of indications with reimbursement in Czechia, 40% in Hungary, 51% in Poland, and 19% in Slovakia. In all countries, a significantly greater proportion of indications with a substantial clinical benefit was reimbursed (P < 0.05). The median waiting time to reimbursement ranged from 27 months in Poland to 37 months in Hungary. No significant differences in waiting time in relation to clinical benefit were observed in any country (P = 0.25-0.84).

CONCLUSIONS

Cancer medicines with a substantial clinical benefit are more likely to be reimbursed in all four CEE countries. Waiting times to reimbursement are equally long for medicines with or without a substantial clinical benefit, indicating a lack of prioritization of fast access to medicines delivering a substantial benefit. Incorporation of the ESMO-MCBS in reimbursement assessments and decisions could aid in better utilization of limited resources to deliver more effective cancer care.

Effects of Vitamin D Supplementation on Telomere Length: An Analysis of Data from the Randomised Controlled D-Health Trial

OBJECTIVES

Observational studies have suggested that a higher 25-hydroxyvitamin D concentration may be associated with longer telomere length; however, this has not been investigated in randomised controlled trials. We conducted an ancillary study within a randomised, double-blind, placebo-controlled trial of monthly vitamin D (the D-Health Trial) for the prevention of all-cause mortality, conducted from 2014 to 2020, to assess the effect of vitamin D supplementation on telomere length (measured as the telomere to single copy gene (T/S) ratio).

DESIGN, SETTING, PARTICIPANTS, AND INTERVENTION

Participants were Australians aged 60-84 years and we randomly selected 1,519 D-Health participants (vitamin D: n=744; placebo: n=775) for this analysis. We used quantitative polymerase chain reaction to measure the relative telomere length (T/S ratio) at 4 or 5 years after randomisation. We compared the mean T/S ratio between the vitamin D and placebo groups to assess the effect of vitamin D supplementation on relative telomere length, using a linear regression model with adjustment for age, sex, and state which were used to stratify the randomisation.

RESULTS

The mean T/S ratio was 0.70 for both groups (standard deviation 0.18 and 0.16 for the vitamin D and placebo groups respectively). The adjusted mean difference (vitamin D minus placebo) was -0.001 (95% CI -0.02 to 0.02). There was no effect modification by age, sex, body mass index, or predicted baseline 25-hydroxyvitamin D concentration.

CONCLUSION

In conclusion, routinely supplementing older adults, who are largely vitamin D replete, with monthly doses of vitamin D is unlikely to influence telomere length.

The need for multipurpose prevention technologies in sub-Saharan Africa

Women bear a disproportionate burden of the HIV epidemic in sub-Saharan Africa and account for about 60% of all adults living with HIV in that region. Young women, including adolescent girls, unable to negotiate mutual faithfulness and/or condom use with their male partners are particularly vulnerable. In addition to the high HIV burden, women in Africa also experience high rates of other sexually transmitted infections and unwanted pregnancies. The development of technologies that can simultaneously meet these multiple sexual reproductive health needs would therefore be extremely beneficial in the African setting.

Microbicides and their potential as a catalyst for multipurpose sexual and reproductive health technologies

There is an urgent need for technologies to prevent sexual acquisition of HIV infection in young women in sub-Saharan Africa. After two decades of 11 pivotal trials of seven products, anti-retroviral-based topical microbicides are showing promise. Building on the CAPRISA 004 trial findings, several trials of new anti-viral agents, novel delivery mechanisms and combination/multipurpose products that address challenges of adherence and meet the sexual and reproductive health needs of men and women, including preventing HIV infection, are underway.

Contributions of John Henry Poynting to the understanding of radiation pressure

The name of Poynting is universally recognized for his development of the well-known expression for the flow of electromagnetic energy. Not so well known is Poynting's series of papers on radiation pressure, with 2011 marking the centenary of the last of his 15 publications on this topic. This paper reviews and assesses his radiation-pressure work, with a level of coverage aimed at the reader familiar with the Maxwell electromagnetic theory and interested in the current understanding of radiation pressure. We begin with brief details of Poynting's life, followed by accounts of the relevant publications by others before and during his period of activity in the field from 1903 to 1911. His contributions to the understanding of radiation-pressure effects in the solar system, and the linear and angular momenta of light are discussed, with evaluations from a modern perspective.

Swallows as indicators of environmental pollution of the Rio Grande/Rio Bravo Basin: are persistent organic pollutants a concern?

Swallows from two locations in the Rio Grande/Rio Bravo Basin and one reference site located 500 km away were analyzed for organochlorine pesticides (OCs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). Of the OC pesticides, only p,p'-DDE was observed at levels of concern (carcass geometric mean range 642 to 8511 ng/g wet weight [ww]). DDE residues in carcass were significantly greater at El Paso than at other locations. PCBs were relatively low compared with locations in the northeastern United States and the Great Lakes. Geometric mean PBDE concentrations ranged from 18 to 258 ng/g ww (280 to 3395 ng/g lipid weight). PBDE congeners 47 and 99 comprised approximately 60% of total PBDEs. Concentrations of DDE measured in swallows from El Paso in 2000 and 2005 are among the highest observed in the last 20 years along the United States-Mexico border. The results from this study indicated that swallows are still being exposed to high concentrations of DDE, which could have adverse effects on reproduction or on predators that feed on swallows.

PBDEs, PCBs, and DDE in eggs and their impacts on aplomado falcons (Falco femoralis) from Chihuahua and Veracruz, Mexico

Eggs from aplomado falcons (Falco femoralis septentrionalis) nesting in Chihuahua and Veracruz, Mexico, were analyzed for organochlorine pesticides, PCBs, and PBDEs. p,p'-DDE was the only organochlorine found in all eggs at concentrations ranging from 0.13 to 7.85 μg/g wet weight. PCBs ranged from 0.04 to 2.80 μg/g wet weight and PBDEs from 62 to 798 ng/g lipid weight. DDE concentrations in eggs were not significantly different among regions; however, PCBs were significantly greater (P = 0.015) in Tinaja Verde, Chihuahua than in the other three regions. Also, PBDEs were significantly higher (P < 0.0001) in eggs from Veracruz than in those from Chihuahua. DDE concentrations in eggs were much lower than those associated with eggshell thinning. PBDEs and PCBs were lower than those reported in raptors from industrialized countries. Overall, contaminant concentrations observed suggest no likely impact on hatching success. The PBDE concentrations are among the first to be reported in raptor species in Mexico.

Group cognitive-behavioral therapy for patients with epilepsy and comorbid depression and anxiety

Clinical Practice Guidelines for depression and anxiety recommend cognitive-behavioral therapy (CBT) as an equivalent and sometimes more effective treatment than medication. The limited research investigating CBT for anxiety and depression in epilepsy demonstrates mixed results. Described here is a pilot project using an existing group CBT intervention for symptoms of depression and/or anxiety, CBT Basics II, in patients with epilepsy. Eighteen patients with epilepsy, referred by neurologists to address depression and/or anxiety symptoms, completed the 10-week group. Results demonstrated improvements in depression, anxiety, negative automatic thoughts, and cognitive therapy knowledge and skills. The group was generally acceptable to patients as indicated by good attendance rates and only one dropout. This pilot project demonstrates that group CBT is a feasible, acceptable, and promising intervention for patients with epilepsy and comorbid depression and anxiety symptoms.

Phosphorus bioavailability, growth performance, and nutrient balance in pigs fed high available phosphorus corn and phytase

Three experiments were conducted to evaluate P bioavailability, growth performance, and nutrient balance in pigs fed high available P (HAP) corn with or without phytase. The bioavailability of P in normal and HAP corn relative to monosodiumphosphate (MSP) for pigs was assessed in Exp. 1. In a randomized complete block design, 96 pigs (average initial BW 9.75 kg) were fed eight diets for 28 d. The reference and test diets were formulated by adding P as MSP, HAP, or normal corn at 0, 0.75, or 1.5 g/kg to a corn-starch-soybean meal basal diet (2.5 g/kg P) at the expense of cornstarch. Plasma inorganic P concentration responded linearly (P < 0.05) to supplemental P intake. Estimates of P bioavailability from HAP andnormal corn when plasma P was regressed on supplemental P intake were 46 and 33%, respectively. In Exp. 2 and 3, pigs were fed corn-soybean meal-based diets containing HAP corn or normal corn and 0 or 600 units of phytase per kilogram in a 2 x 2 factorial arrangement (two corn sources and two levels of phytase). In Exp. 2, 48 crossbred pigs (barrow:gilt, 1:1) averaging 9.25 kg were used to evaluate growth performance. There were no detectable interactions between corn source and phytase for any of the performance criteria measured. Pigs receiving normal corn had the lowest (P < 0.05) BW and rate of gain. Feed efficiency was lower (P < 0.05) in pigs fed normal compared with those fed the HAP corn phytase-supplemented diet. In Exp. 3, 24 crossbred barrows averaging 14.0 kg were used to evaluate nutrient digestibility. There were no detectable interactions between corn and phytase for any of the N and Ca balance criteria. Nitrogen and Ca retention were improved in pigs receiving HAP corn with phytase (P < 0.05). Retention and digestibility of P was lowest (P < 0.01) for pigs on normal corn diet without phytase. The percentage of P digested and retained was improved and fecal P excretion lowered (P < 0.05) by feeding HAP corn. The results of this study indicate that the bioavailability and balance of P in HAP corn is superior to that of normal corn. The addition of 600 phytase units (Natuphos 600, BASF) to HAP corn-based diets further improved P digestibility and reduced P excretion in pigs.

Sacral and ischial pressure ulcers: evaluation, treatment, and differentiation

Although the cost of caring for pressure ulcers is enormous, few accepted standards of care exist in the fragmented specialty of wound care. This review attempts to establish a standardized approach to the evaluation and treatment of sacral and ischial wounds, and to describe some important differences. Topics reviewed include important elements of the history, physical, and laboratory studies of patients with wounds. Treatment issues are also addressed including wound care, pressure relief, and nutrition. The authors hope that the principles discussed will stimulate caregivers to examine their practices, and will serve as a starting point for formation of more exacting accepted care. While each patient and wound may require subtle nuances of care in certain areas, a more uniform set of standards will be the first step in creating delivery systems that are geared for large-scale prospective randomized studies that are so desperately needed in most areas of wound care.

A comparison of energy expenditure by a high level trans-femoral amputee using the Intelligent Prosthesis and conventionally damped prosthetic limbs

Comparisons were made between the Intelligent Prosthesis (IP), Mauch and pneumatic swing phase control damping systems on the same prosthesis worn by a high level trans-femoral amputee. Speeds self selected by corridor walking (4.4-5.5 kmh-1) proved not to be sustainable for treadmill walking. Comfortable speeds were attained when the subject walked on a treadmill at 2.0, 2.6 and 3.2 kmh-1 in two tests for each prosthesis type. Oxygen uptake (VO2), cadence and heart rate were measured over 5 minute walks interspersed with rest periods. Spearman's correlation was used to test for differences between prosthesis types at each speed. At the two slower speeds no significant difference was found, but at the higher speed of 3.2 kmh-1, the IP was associated with a significantly lower VO2 (p < 0.05). A two way analysis of variance with replication (ANOVA) demonstrated a significant difference between VO2 for different limb types (p = 0.015). A square law function was fitted to the mean VO2 for each prosthesis type by the method of least squares regression. ANOVA demonstrated a significant difference between velocity coefficients for the different prosthesis types (p < 0.05). Cadence was almost constant during the period of each walk, varying by 1 step min-1 at most. However the test-retest differences in cadence were considerable. It is concluded that there was little difference in energy expenditure between prosthesis types at slower speeds, but at higher speeds (==> 3.2km h-1) the IP gave a lower oxygen uptake by about 10%.

Effect of a bradykinin antagonist on the local inflammatory response following thermal injury

Partial and full thickness burns with intervening zones of stasis were created on the backs on New Zealand White rabbits (n = 23). Either saline or the bradykinin receptor antagonist, NPC 17731, was administered. Skin blood flow was measured hourly using a laser Doppler blood flowmeter. After 4 h skin samples were harvested for assessment of tissue oedema (wet/dry weights) and leucocyte accumulation (immunohistochemistry). Statistical analysis was performed using Analysis of variance (ANOVA) and Mann-Whitney U test with a level of significance at P < 0.05. It was found that blood flow was decreased postburn in all groups. Bradykinin antagonist resulted in increased blood flow in partial thickness burns and zones of stasis compared to saline-treated animals (P < 0.05). Pretreatment with bradykinin antagonist showed reduced tissue oedema in full thickness burns (P < 0.05). No significant difference was observed in leucocyte accumulation between both groups. These data suggest a role for bradykinin in the pathogenesis of postburn microvascular changes which is independent of leucocyte-mediated injury.

Early assessment of pediatric burn wounds by laser Doppler flowmetry

Evaluation of burn wound depth in pediatric patients is often difficult. A Laser Doppler Flowmeter with a temperature-controlled multichannel probe was used to measure burn wound perfusion as a tool to predict wound outcome. The average perfusion levels for wounds that healed spontaneously in fewer than 21 days was significantly higher than the average perfusion levels for wounds that required excision and grafting or were not healed by day 21 after burn injury. Laser Doppler Flowmetry showed high positive predictive values for "nonhealing" wounds on postburn days 1, 2, and 3. These results suggest that Laser Doppler Flowmetry is a useful tool for burn wound assessment in pediatric patients.

Laser Doppler flowmetry in burn wounds

Traditional methods for judgment of burn depth by clinical evaluation of the wound based on appearance and sensation remain in wide use but are subject to individual variation by examiner. In addition to the clinical difficulties with burn wound management, observer dependency of wound assessment complicates clinical trials of burn wound therapy. A laser Doppler flowmeter with a newly designed multichannel probe was used to measure burn wound perfusion as a tool to predict wound outcome. Wounds that healed spontaneously in fewer than 21 days showed higher average perfusion levels than those that required excision and grafting or that were not healed by day 21 after the burn. Laser Doppler flowmetry had a positive predictive value of 100% for nonhealing wounds on postburn days 1 and 3. These data suggest that laser Doppler flowmetry is a potentially useful tool for burn wound assessment.

Thresholds for treatment in cataract surgery

BACKGROUND

The aim of the study was to identify the criteria used by ophthalmologists when assessing patients who may require cataract surgery, examine the extent of variation in their application and explore their relationship with current patterns of supply and demand.

METHODS

This was a descriptive study involving semi-structured interviews with ophthalmologists, examination of hospital clinical records, and analysis of routinely available data on waiting times and hospital activity. The setting was ophthalmology units within the Northern Region of England. The subjects were 27 consultant ophthalmologists and 160 patients undergoing cataract extraction.

RESULTS

There was agreement amongst ophthalmologists on the criteria used to select patients for treatment, and on the visual acuity level at which they would usually recommend surgery. All assess the degree of handicap resulting from cataract; most consider this more important than visual acuity. Over half of the patients were over 75 years old; two-thirds were women. Median visual acuity at listing was 6/36, but over 40 per cent were 6/60 or worse. Visual acuity at treatment was not recorded for 32 per cent of patients. Wide variation in visual acuity at listing existed between both units and consultants, and for both the affected and other eye. Second extractions may be performed at a better level of visual acuity than for first extractions. Median visual acuity at listing was significantly correlated with total waiting times for individual consultants. Lower cataract extraction rates are associated with long waiting times and poorer visual acuity at listing.

CONCLUSIONS

There is considerable unmet need for cataract treatment within the Northern Region and significant variation in the current meeting of needs and demands. It may be that more needs could be met simply by changing referral and treatment patterns without increasing total service activity. Although visual acuity is a reasonably objective measure in routine use, the level of visual handicap is more important, and its assessment is more subjective; development of a standard method to assess this could help in producing guidelines for patient referral and selection. Audit of treatment thresholds could allow a better matching of service provision to population needs.

Effect of inhibiting leukocyte integrin (CD18) and selectin (L-selectin) on susceptibility to infection with Pseudomonas aeruginosa

Leukocyte (WBC) adherence to endothelial cells has been implicated in the pathogenesis of microvascular injury. The process of leukocyte adherence is mediated by both the integrin and selectin families of molecules, and their interaction with specific endothelial ligands. Antibodies directed against the leukocyte integrin CD18 and L-selectin have been developed and functionally inhibit leukocyte adherence in models of inflammatory injury. We asked the question: Does inhibition of leukocyte adherence by administration of monoclonal antibody directed against either CD18, integrins (R15.7, R7.1) or against L-selectin (DREG 200) increase susceptibility to infection? New Zealand white rabbits were shaved and injected subcutaneously on their dorsum with Pseudomonas aeruginosa (ATCC#27853) at two sites each of 10(8) and 10(7) colony forming units. Animals were monitored with daily determination of weight, temperature, WBC counts, hematocrit, and killed at 1 week for determination of abscess formation. There were four blinded experimental groups: (1) Saline (2 mL/kg); (2) DREG 200 (2 mg/kg); (3) R7.1 (2 mg/kg); or (4) R15.7 (2 mg/kg). At the 10(7) and 10(8) injection sites the R15.7 group had an increased rate and size of abscess formation compared with controls. The R7.1 group had an increased rate at the 10(8) injection site. There was no significant difference in the percentage of the abscess formation or mean area between the controls and DREG 200-treated groups. We conclude that giving antibody to CD18 increased susceptibility to infection while giving antibody to L-selectin does not.

Inhibition of leukocyte adherence in a rabbit model of major thermal injury

Leukocytes and the process of leukocyte adherence have been implicated in the pathogenesis of organ dysfunction after ischemic injury and inflammation. We asked the question: Will inhibition of leukocyte adherence by administration of a monoclonal antibody to intercellular adhesion molecule alter the systemic response to major thermal injury? New Zealand white rabbits instrumented to measure mean arterial pressure, cardiac output, urine output, and arterial oxygenation were deeply anesthetized, and 30% total body surface area full-thickness burn was created by applying brass probes heated to 100 degrees C to the animals' backs for 15 seconds. The animals were continuously monitored, resuscitated, and given analgesic for 24 hours. There were three experimental groups: I-controls (n = 7), anesthetized and monitored; II-30% burn (n = 7) given 30% total body surface area + vehicle (saline solution 1.0 ml/kg every 8 hours); III-30% burn + R6.5 (n = 6) animals given a monoclonal antibody (R6.5, 2.0 mg/kg every 8 hours) directed against the intercellular adhesion molecule beginning 30 minutes after burn. This model of a 30% total body surface area burn injury resulted in hypotension and hypoxemia in the burn group. The animals given the antibody R6.5 maintained higher mean arterial pressure and arterial oxygenation at several points. These results suggest that leukocytes and leukocyte adherence may be involved in the pathogenesis of the systemic sequellae of major thermal injury.

Changes in exogenous surfactant in ventilated preterm lamb lungs

Preterm lambs were treated with either a surfactant from bovine lung (Survanta) or three synthetic surfactants (Exosurf), a 69:22:9 mixture of dipalmitoylphosphatidylcholine, phosphatidylglycerol, and palmitic acid prepared by heat annealing (Lipid Mixture 1) or with glass beads (Lipid Mixture 2). After 5 h of ventilation, large and small aggregate surfactant fractions were isolated from alveolar washes by centrifugation. SP-A was used as an indicator for the association of endogenous surfactant components with the treatment surfactants. The large aggregate fraction from Survanta-treated lambs contained more SP-A than did the fractions from the lambs treated with the other surfactants (p < 0.05). The surfactants used to treat the sheep and the large aggregate surfactants from alveolar washes increased compliances when tested in surfactant-deficient, immature rabbits, relative to that in control animals. The large aggregate fractions in alveolar washes from lambs treated with Survanta, Lipid Mixture 1, and Lipid Mixture 2 improved compliances in the preterm rabbits to a greater extent than did the surfactants used to treat the lambs. The small aggregate fractions were inactive as surfactants. The function of exogenous surfactant can be improved after exposure to the preterm lung. The improvement may result from the association of exogenous surfactant with components of endogenous surfactant.

Inhibition of leukocyte adherence and susceptibility to infection

Leukocyte (WBC) adherence to endothelial cells (EC) has been implicated in the pathogenesis of microvascular injury. WBC-EC adherence is largely dependent on interaction between the WBC-CD18 complex and the endothelial ligand, intercellular adhesion molecule-1 (ICAM-1). Administration of monoclonal antibodies directed against CD18 and/or ICAM-1 inhibit WBC-EC adherence and have been reported to modulate ischemia-reperfusion and inflammatory injury. We asked the question, does inhibition of WBC-EC adherence by administration of monoclonal antibody directed against either CD18 (R15.7) or against ICAM-1 (R6.5) increase susceptibility to infection. New Zealand white rabbits were shaved and injected subcutaneously on their dorsum with Staphylococcus aureus (ATCC No. 25923) at two sites each with 10(9), 10(8), 10(7), and 10(6) colony-forming units (CFUs). A second set of rabbits were injected subcutaneously with Pseudomonas aeruginosa (ATCC No. 27853) at two sites each of 10(8) and 10(7) CFUs. Animals were monitored for 1 week with daily determination of weight, temperature, WBC counts, hematocrit, and gross evidence of abscess formation. There were three blinded experimental groups; animals given R15.7 (2.0 mg/kg), animals given R6.5 (2.0 mg/kg), and controls given saline (2.0 ml/kg). Administration of the anti-CD18 antibody, R15.7, resulted in significantly increased rates of abscess formation following innoculation with S. aureus and with P. aeruginosa, compared to controls and to the animals given the antibody to ICAM-1, R6.5. The administration of R6.5 did not increase the incidence or severity of abscess formation.

Structure and functions of a dimeric form of surfactant protein SP-C: a Fourier transform infrared and surfactometry study

Surfactant proteins SP-B (M(r) = 8700, reduced) and SP-C (M(r) = 3000-6000, major form, non-reduced) interact with surfactant phospholipids to enhance their surface active properties. In the present study, we describe the structural and functional characteristics of a novel dimeric form of bovine SP-C (M(r) = 9000, non-reduced), which is identified as [SP-C]2. Dimeric SP-C exhibits surface tension-lowering properties differing from those of monomeric SP-C and enhances the surface properties of bovine SP-B/phospholipid mixtures. Chemical analysis indicated that [SP-C]2 was not acylated at the cysteinyl residues. Fourier transform-infrared spectroscopy (FT-IR) was utilized to determine the secondary structures of [SP-C]2 in DPPC films. Relative percentages of alpha-helical, beta-sheet, beta-turn and random coil structures were calculated by peak fit analysis of the amide I band of the FT-IR spectra indicating that, in contrast to the helical structure of monomeric SP-C, [SP-C]2 exhibits almost exclusively beta-sheet structure. In addition, only 10% of the amide (backbone) hydrogens exchanged with deuterium of D2O, indicating that the remaining 90% of amide hydrogens were not accessible to D2O due to strong hydrogen bonding or their location in a hydrophobic environment. Dimerization of SP-C effects a major change in secondary structure, a factor which may play a role in the interaction of SP-C with phospholipids in pulmonary surfactant.

Inhibition of leukocyte-endothelial adherence following thermal injury

Progressive microvascular damage in the tissue adjacent to a cutaneous burn injury results in extension of burn size. The role of neutrophils (PMNs) in the pathogenesis of microvascular injury was investigated by inhibition of PMN adherence to the microvascular endothelium using monoclonal antibodies directed to the leukocyte CD18 adhesion complex or its endothelial ligand, intercellular adhesion molecule-1 (ICAM-1, CD54). A model of thermal injury was developed using New Zealand White rabbits. Under general anesthesia two sets of three full-thickness burns separated by two 5 x 30-mm zones were produced by applying brass probes heated to 100 degrees C to the animals' backs for 30 sec. Cutaneous blood flow determinations were obtained for 72 hr. Blood flow measurements were performed using a laser doppler blood flowmeter (PF3, Perimed, Piscataway, NJ). There were five experimental groups; controls given saline alone, n = 12; animals given monoclonal antibody to the PMN CD18 complex, R 15.7 prior to burn injury (pre-R15.7, n = 5); animals given R 15.7 30 min after burn injury (post-R 15.7, n = 6); animals given the anti ICAM-1 antibody, R 6.5 prior to burn (pre-R 6.5, n = 6); and animals given the R 6.5 30 min postburn injury (post-R 6.5, n = 6). BF in the marginal "zone of stasis" between burn contact sites was significantly higher in the antibody-treated animals and administration of the antibodies 30 min after injury was as effective as preburn administration in preserving blood flow.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of surfactant-associated protein SP-B synthetic analogs on the structure and surface activity of model membrane bilayers

The effect of several synthetic peptides based on the sequence of human pulmonary surfactant-associated protein B (SPB) on the molecular packing of model membrane lipids (7:1 dipalmitoyl phosphatidylcholine (DPPC)/dipalmitoyl phosphatidylglycerol (DPPG)) was studied using fluorescence anisotropy. This information was then correlated with complementary biophysical data obtained on both a modified Wilhelmy-Langmuir balance and a pulsating bubble surfactometer. The SP-B peptides examined in these studies are synthetic human SP-B Phe1-Ser78 (SP-B 1-78, full-length sequence), synthetic human SP-B Phe1-Thr60 (SP-B 1-60), synthetic human SP-B Phe1-Ala20 (SP-B 1-20), synthetic human SP-B Ala20-Thr60 (SP-B 20-60), synthetic human SP-B Leu27-Ser78 (SP-B 27-78), synthetic human SP-B Leu40-Thr60 (SP-B 40-60) and synthetic human SP-B Tyr53-Ser78 (SP-B 53-78). trans-parinaric acid was utilized to detect changes in ordering of lipids within the interior upon incorporation of synthetic SP-B peptide, whereas 1-hexadecanoyl-2-[N-(7-nitro-2-benzoxa-1,3-diazol-4-yl)-a min ohexanoyl] phosphatidylcholine (6-NBD-PC) and 1-acyl-2-[N-(7-nitro-2-benzoxa-1,3-diazol-4-yl)aminohexanoyl ] phosphatidylglycerol (6-NBD-PG) were utilized to determine alterations in lipid order at the surface of the model membrane bilayer. With the exception of SP-B 40-60, which corresponds to the most hydrophobic segment of the full-length SP-B, none of the other peptide significantly perturbed the interior bilayer as determined by fluorescence anisotropy of trans-parinaric acid. Incorporation of any of the peptides with the exception of SP-B 40-60, resulted in an increase in anisotropy of NBD-PC. The most significant enhancements resulted from the addition of SP-B 1-78, SP-B 1-20, SP-B 27-78 or SP-B 53-78. The magnitude of anisotropy increase with these peptides is similar to that observed with an equivalent molar ratio of native SP-B isolated from a bovine source. These observations suggest that these four synthetic peptides have the structural and compositional characteristics required for surface ordering of the membrane bilayer in a manner similar to that observed with native SP-B, thereby facilitating the surfactant-like properties of phospholipid mixtures.

Race and child abuse

Very little is known about the relationship between race and child abuse. Skills in prevention, detection and family support have not increased at the same pace as for the majority population. This article looks at some of the factors associated with child abuse in black and ethnic minority communities and suggests how health professionals can improve their skills in working with this section of our population.

Brucellosis in an inuit child, probably related to caribou meat consumption

A 9-year-old Inuit boy with brucellosis is presented. The most likely source of his infection was contaminated caribou meat. Brucella suis is enzootic in Canadian caribou herds and this case indicates that natives of the Arctic are a risk group for acquiring brucellosis through the ingestion of raw caribou meat.

Racial inequalities in health: a challenge to the British National Health Service

The existence of racial inequalities in health in the United Kingdom is examined using both indirect and direct data. The evidence strongly supports the view that the health experience of black and other ethnic minority groups is worse than that of the indigenous white population. Ways of improving this situation are outlined; they indicate the need for a coordinated Health service response incorporating planning, training, and equal opportunities in both service provision and employment practices.