Impact of mitral valve annuloplasty on mortality risk in patients with mitral regurgitation and left ventricular systolic dysfunction

OBJECTIVES

This study was designed to assess effects of mitral valve annuloplasty (MVA) on mortality in patients with mitral regurgitation (MR) and left ventricular (LV) systolic dysfunction.

BACKGROUND

Mitral valve annuloplasty improves hemodynamics and symptoms in these patients, but effects on long-term mortality are not well established.

METHODS

We retrospectively analyzed consecutive patients with significant MR and LV systolic dysfunction on echocardiography between 1995 and 2002. Cox regression analysis, including MVA as a time-dependent covariate and propensity scoring to adjust for differing probabilities of undergoing MVA, was used to identify predictors of death, LV assist device implantation, or United Network for Organ Sharing-1 heart transplantation.

RESULTS

Of 682 patients identified, 419 were deemed surgical candidates; 126 underwent MVA. Propensity score derivation identified age, ejection fraction, and LV dimension to be associated with undergoing MVA. End points were reached in 120 (41%) non-MVA and 62 (49%) MVA patients. Increased risk of end point was associated with coronary artery disease (hazard ratio [HR] 1.80, 95% confidence interval [CI] 1.30 to 2.49), blood urea nitrogen (HR 1.01, 95% CI 1.005 to 1.02), cancer (HR 2.77, 95% CI 1.45 to 5.30), and digoxin (HR 1.66, 95% CI 1.15 to 2.39). Reduced risk was associated with angiotensin-converting enzyme inhibitors (HR 0.65, 95% CI 0.44 to 0.95), beta-blockers (HR 0.59, 95% CI 0.42 to 0.83), mean arterial pressure (HR 0.98, 95% CI 0.97 to 0.99), and serum sodium (HR 0.93, 95% CI 0.90 to 0.96). Mitral valve annuloplasty did not predict clinical outcome.

CONCLUSIONS

In this analysis, there is no clearly demonstrable mortality benefit conferred by MVA for significant MR with severe LV dysfunction. A prospective randomized control trial is warranted for further study of mortality with MVA in this population.

A new method for detection of pfmdr1 mutations in Plasmodium falciparum DNA using real-time PCR

BACKGROUND

Surveillance for drug-resistant Plasmodium falciparum should be a component of malaria control programmes. Real-time PCR methods for the detection of parasite single-nucleotide polymorphisms (SNPs) and gene amplification could be useful survellance tools.

METHODS

A real-time PCR assay has been developed that identifies single nucleotide polymorphisms (SNPs) at amino acids 86, 184, 1034 and 1042 in the P. falciparum multi-drug resistant (pfmdr 1) gene that may be associated with anti-malarial drug resistance.

RESULTS

This assay has a sensitivity and specificity of 94% and 100% when compared to traditional PCR methods for genotyping. Only 54 of 68 (79%) paired pre- and post-culture DNA samples were concordant at all four loci.

CONCLUSION

Real-time PCR is a sensitive and specific method to detect SNP's in pfmdr 1. Genotypes of parasites after in vitro culture may not reflect that seen in vivo.

Incidence of and socio-demographic risk factors for stillbirth, preterm birth and low birthweight among Zimbabwean women

Data on birth outcomes are important for planning maternal and child health care services in developing countries. Only a few studies have examined frequency of birth outcomes in Zimbabwe, none of which has jointly examined the spectrum of poor birth outcomes across important demographic subgroups. We assessed delivery patterns and birth outcomes in 17 174 births over a one-year period from October 1997 to September 1998 at Harare Hospital, Zimbabwe. The annual rate of stillbirth was 61 per 1000 live births, rate of preterm birth (<37 weeks) was 168 per 1000, and low birthweight (LBW) (<2500 g) was 199 per 1000. Not attending antenatal care (prenatal care) was associated with increased risks of stillbirth [relative risk (RR) = 2.54, 95% CI 2.21, 2.92], preterm delivery [RR = 2.43, 95% CI 2.26, 2.61] and LBW births [RR = 2.16, 95% CI 2.02, 2.31]. Preterm births and LBW births were more likely to be stillborn [RR = 7.26, 95% CI 6.28, 8.39 and RR = 6.85, 95% CI 5.94, 7.91]. In conclusion, the rate of stillbirth is high and is predominantly associated with preterm births and to a lesser extent LBW. Reducing the frequency of stillbirth will require a better understanding of the determinants of preterm births and strategies for addressing this particular subset of high-risk births.

Stress and female reproductive function: A study of daily variations in cortisol, gonadotrophins, and gonadal steroids in a rural Mayan population

We report here on a longitudinal study of stress and women's reproduction in a small Kaqchikel Mayan community in rural Guatemala. Current understanding of the effects of stress on the reproductive axis in women is mostly derived from clinical studies of individual stressors. Little is known, however, about the cumulative effects of "real life" stress. Cortisol increases in response to a broad variety of individual stressors (Tilbrook et al., 2002). In this article, we evaluate the association between daily fluctuations in women's urinary cortisol and reproductive hormones: estrone conjugates (E(1)C), pregnandiol glucuronide (PdG), luteinizing hormone (LH), and follicle stimulating hormone (FSH). To assess the association between daily changes in cortisol levels and changes in the profiles of the reproductive hormones, we used a random coefficients model based on polynomial regression. The sample includes 92 menstrual cycles provided by 24 participants over a year-long prospective study. Increases in urinary cortisol levels were associated with significant increases in gonadotrophin and progestin levels during the follicular phase. Also, in a time window between days 4 and 10 after ovulation, increased cortisol levels were associated with significantly lower progestin levels. These results are significant because untimely increases in gonadotrophins and low midluteal progesterone levels have previously been reported to impinge on the ovulatory and luteinization processes and to reduce the chances of successful implantation (Ferin, 1999; Baird et al., 1999). Future research should consider the possibility that stress may affect fecundability and implantation without necessarily causing amenorrhoea or oligomenorrhoea.

Birthweight-adjusted Dubowitz methods: reducing misclassification of assessments of gestational age in a Zimbabwean population

OBJECTIVE

To evaluate the performance and the utility of using birthweight-adjusted scores of the Dubowitz method of estimating gestational age in a Zimbabwean population.

DESIGN

A validation study.

SETTING

Harare Maternity Hospital, from October to December 1999.

SUBJECTS

364 African newborn infants with a known last menstrual period (LMP), within the first 56 hours of life.

MAIN OUTCOME MEASURES

Differences between regression lines and variances explained by Dubowitz scores obtained by examining newborn infants compared to gestational age calculated from the last menstrual period, in models with and without the addition of birthweight.

RESULTS

The Dubowitz method was a good predictor of gestational age, useful in differentiating term from pre-term infants. The beta coefficients from regression lines with and without addition of birthweight differed significantly from each other (z = 2.83, p < 0.01). Our regression line without adding birthweight was Y(LMP gestational age) = 23.814 + 0.301* score. Addition of birthweight to the regression models improved prediction of gestational age, Y(LMP gestational age) = 23.512 + 0.219* score + 0.0015* grams, and accounted for 69% of the variance compared to 66% in models without birthweight.

CONCLUSION

The introduction of birthweight improves estimation of gestational age, correcting for the overestimation reported for the original Dubowitz methods and the error caused by low birthweight. We recommend the use of our birthweight-adjusted Dubowitz maturity scales for studies of prematurity, and for routine clinical practice.

Central serotonergic effects of m-chlorophenylpiperazine (mCPP) among normal control adolescents

Central serotonin function was studied among 21 adolescents (12 males, 9 females), mean age 14.4+/-1.5 years. A placebo-controlled design was used to measure three neuroendocrine hormones (prolactin, cortisol and growth hormone) following a challenge with the central serotonergic agonist m-chlorophenylpiperazine (mCPP). Infusion of mCPP resulted in augmented prolactin, cortisol and growth hormone release. Gender effects were significant for prolactin, cortisol and growth hormone. Females had higher baseline prolactin without significant interactions with infusion or time, cortisol levels were higher in males than in females at all time points without significant interactions with infusion or time, and the augmented growth hormone response to mCPP was limited to males. Systolic and diastolic blood pressure, heart rate and temperature were all mildly elevated following mCPP infusion. Side effects to mCPP infusion were mild and lasted approximately 20 min. We conclude that mCPP is useful in the study of serotonergic neuroendocrine hormones in adolescents, is well tolerated, and the levels of prolactin, cortisol and growth hormone are influenced by gender.

Improving the assessment of gestational age in a Zimbabwean population

OBJECTIVES

To evaluate the performance and the utility of using birthweight-adjusted scores of Dubowitz and Ballard methods of estimating gestational age in a Zimbabwean population.

METHOD

The Dubowitz and the Ballard methods of estimating gestational age were administered to 364 African newborn infants with a known last menstrual period (LMP) at Harare Maternity Hospital.

RESULTS

Both methods were good predictors of gestational age useful in differentiating term from pre-term infants. Our regression line was Y((LMP gestational age))=23.814+0.301*score for the Dubowitz and Y((LMP gestational age))=24.493+0.420*score for the Ballard method. Addition of birthweight to the regression models improved prediction of gestational age; Y((LMP gestational age))=23.512+0.219*score+0.0015*grams for Dubowitz and Y((LMP gestational age))=24.002+0.292*score+0.0016*grams for Ballard method.

CONCLUSIONS

We recommend the use of our birthweight-adjusted maturity scales; the Dubowitz for studies of prematurity, and the Ballard for routine clinical practice.

Body image and the innocent eye

This paper describes the development, content, teaching experience, and impact of the course "The body image in medicine and the arts" which is offered annually in a one-month format for medical students and other upper division students at the University of Missouri-Kansas City (UMKC). Literature, photography, art, anthropology, art history, cultural studies, feminism, modernism, and medicine are all employed in the course as a way of encouraging students to consider the broader cultural interpretations of the human body. Any medical humanities instructor wishing to explore new ideas and themes related to teaching students about past and present body image issues and their impact on contemporary biomedical culture can gain insight through an overview of this course. The purpose of the course is to allow medical students a forum for talking more personally and metaphorically about the body as a cultural concept. The teaching faculty involved in this course believe that the majority of students who participate in this class complete it more acutely aware than before of the fact that no single human being, even a "good, caring" doctor, can see with an "innocent eye". The accomplishment of this goal alone justifies faculty participation in the course.

Ran-binding protein 3 is a cofactor for Crm1-mediated nuclear protein export

Crm1 is a member of the karyopherin family of nucleocytoplasmic transport receptors and mediates the export of proteins from the nucleus by forming a ternary complex with cargo and Ran:GTP. This complex translocates through the nuclear pores and dissociates in the cytosol. The yeast protein Yrb2p participates in this pathway and binds Crm1, but its mechanism of action has not been established. We show that the human orthologue of Yrb2p, Ran-binding protein 3 (RanBP3), acts as a cofactor for Crm1-mediated export in a permeabilized cell assay. RanBP3 binds directly to Crm1, and the complex possesses an enhanced affinity for both Ran:GTP and cargo. RanBP3 shuttles between the nucleus and the cytoplasm by a Crm1-dependent mechanism, and the Crm1--RanBP3-NES-Ran:GTP quarternary complex can associate with nucleoporins. We infer that this complex translocates through the nuclear pore to the cytoplasm where it is disassembled by RanBP1 and Ran GTPase--activating protein.

Recommendations and illustrations for combining hypnosis and EMDR in the treatment of psychological trauma

Three experienced therapists, trained in hypnosis and EMDR, distilled some tentative hypotheses about the use of hypnosis in EMDR from fifteen cases, two presented here. When a therapist uses hypnosis with EMDR, it seems that the client is having difficulty or the therapist anticipates that the client will have difficulty managing the experiences processed with EMDR. Hypnosis initiated either during the introduction to EMDR or within a therapy session prior to the initiation of EMDR seems to have served two functions. The first function is to activate inner work that prepares the client to use EMDR successfully, and the second function is to facilitate overtly the processing of the traumatic experience. Clients might have two kinds of difficulties in managing affect or distress: (1) they may have a long-standing, irrational and strongly held belief that interferes with managing affect or distress, and (2) they may never have developed the capacity to tolerate intense affect, distress or pain. Should a therapist use hypnosis during the closing down phase of a session without preparing the client with hypnosis during the introduction to EMDR, the therapist should seriously reconsider the pace and focus of EMDR and the client's resources to manage affect and distress.

Evaluation of a cerebral oximeter as a monitor of cerebral ischemia during carotid endarterectomy

BACKGROUND

Stroke is an important contributor to perioperative morbidity and mortality associated with carotid endarterectomy (CEA). This investigation was designed to compare the performance of the INVOS-3100 cerebral oximeter to neurologic function, as a means of detecting cerebral ischemia induced by carotid cross-clamping, in patients undergoing carotid endarterectomy with cervical plexus block.

METHODS

Ninety-nine patients undergoing 100 CEAs with regional anesthesia (deep or superficial cervical plexus block) were studied. Bilateral regional cerebrovascular oxygen saturation (rSO2) was monitored using the INVOS-3100 cerebral oximeter. Patients were retrospectively assigned to one of two groups: those in whom a change in mental status or contralateral motor deficit was noted after internal carotid clamping (neurologic symptoms; n = 10) and those who did not show any neurologic change (no neurologic symptoms; n = 90). Data from 94 operations (neurologic symptoms = 10 and no neurologic symptoms = 84) were adequate for statistical analyses for group comparisons. A relative decrease in ipsilateral rSO2 after carotid occlusion (calculated as a percentage of preocclusion value) during all operations (n = 100) was also calculated to determine the critical level of rSO2 decrease associated with a change in neurologic function.

RESULTS

The mean (+/- SD) decrease in rSO2 after carotid occlusion in the neurologic symptoms group (from 63.2 +/- 8.4% to 51.0 +/- 11.6%) was significantly greater (P = 0.0002) than in the no neurologic symptoms group (from 65.8 +/- 8.5% to 61.0 +/- 9.3%). Logistic regression analysis used to determine if a change in rSO2, calculated as a percentage of preclamp value, could be used to predict change in neurologic function was highly significant (likelihood ratio chi-square = 13.7; P = 0.0002). A 20% decrease in rSO2 reading from the preclamp baseline, as a predictor of neurologic compromise, resulted in a sensitivity of 80% and specificity of 82.2%. The false-positive rate using this cutoff point was 66.7%, and the false-negative rate was 2.6%, providing a positive predictive value of 33.3% and a negative predictive value of 97.4%.

CONCLUSION

Monitoring rSO2 with INVOS-3100 to detect cerebral ischemia during CEA has a high negative predictive value, but the positive predictive value is low.

Feeding interactions for children with cerebral palsy: contributions of mothers' psychological state and children's skills and abilities

This study examined the relative importance of children's feeding skills and abilities and mothers' psychological state regarding their child's diagnostic status in predicting the observed quality of mother-child interaction during a naturalistic feeding situation. The study subjects were 69 children with cerebral palsy (CP), aged 14 to 53 months, and their mothers. Functional impairments of the children ranged from mild to severe. Mother-child interaction was observed during 20 minutes of feeding and was scored using global ratings of mothers' and children's socioemotional behavior. In addition, mothers' feeding interactions were dichotomously coded for sensitive and responsive behaviors. Children's feeding skills and abilities were assessed by maternal report and by observation. Mothers' resolution of grief associated with the child's diagnosis was assessed using standardized interview procedures. The findings strongly indicate that, contrary to expectations, the mothers' resolution status was not related to qualities of the feeding interactions (either dyadic or mothers' behavior) and that feeding interactions are best predicted for children with CP by their skills and abilities. The results are discussed in relation to the nature, determinants, and consequences of feeding in children with and without disabilities.

Interleukin-4 augments acetylated LDL-induced cholesterol esterification in macrophages

Activated subpopulations of lymphocytes and mast cells have been detected in atherosclerotic lesions. Interleukin-4 (IL-4) is a prominent cytokine released during activation of both cell types and its transcripts have been detected in both human and mouse atherosclerotic lesions. To define whether this local release of IL-4 influences macrophage lipid metabolism, we examined the effects of this cytokine on intracellular cholesterol esterification during incubation with modified low density lipoprotein (LDL). IL-4 greatly augmented cholesterol esterification induced by acetylated LDL (AcLDL) in both mouse peritoneal macrophages and the murine macrophage cell line, J774. This augmentation was maximal at a concentration of 1 ng/ml after incubation for 48 h. This was not a generalized effect on lipoprotein metabolism as IL-4 had no effect on cholesterol esterification in the presence of either LDL or beta-VLDL. Determination of binding isotherms demonstrated that IL-4 increased the number of cell surface binding sites for AcLDL. The IL-4-augmented AcLDL-induced cholesterol esterification was attenuated by the scavenger receptor class A (SR-A) antagonist, fucoidan, and the anti-mouse SR-A monoclonal antibody, 2F8. These data, combined with the known receptor specificity of AcLDL interactions, imply a role of SR-A in the IL-4 induced responses. Two cytokines that have been demonstrated previously to down-regulate SR-A, TNF-alpha and TGF-beta, antagonized the IL-4-induced augmentation of cholesterol esterification. Therefore, local release of IL-4 within atherosclerotic lesions could have a profound effect on macrophage lipid metabolism and the subsequent atherogenic process.

RanBP3 contains an unusual nuclear localization signal that is imported preferentially by importin-alpha3

The full range of sequences that constitute nuclear localization signals (NLSs) remains to be established. Even though the sequence of the classical NLS contains polybasic residues that are recognized by importin-alpha, this import receptor can also bind cargo that contains no recognizable signal, such as STAT1. The situation is further complicated by the existence of six mammalian importin-alpha family members. We report the identification of an unusual type of NLS in human Ran binding protein 3 (RanBP3) that binds preferentially to importin-alpha3. RanBP3 contains a variant Ran binding domain most similar to that found in the yeast protein Yrb2p. Anti-RanBP3 immunofluorescence is predominantly nuclear. Microinjection of glutathione S-transferase-green fluorescent protein-RanBP3 fusions demonstrated that a region at the N terminus is essential and sufficient for nuclear localization. Deletion analysis further mapped the signal sequence to residues 40 to 57. This signal resembles the NLSs of c-Myc and Pho4p. However, several residues essential for import via the c-Myc NLS are unnecessary in the RanBP3 NLS. RanBP3 NLS-mediated import was blocked by competitive inhibitors of importin-alpha or importin-beta or by the absence of importin-alpha. Binding assays using recombinant importin-alpha1, -alpha3, -alpha4, -alpha5, and -alpha7 revealed a preferential interaction of the RanBP3 NLS with importin-alpha3 and -alpha4, in contrast to the simian virus 40 T-antigen NLS, which interacted to similar extents with all of the isoforms. Nuclear import of the RanBP3 NLS was most efficient in the presence of importin-alpha3. These results demonstrate that members of the importin-alpha family possess distinct preferences for certain NLS sequences and that the NLS consensus sequence is broader than was hitherto suspected.

Absence of T lymphocyte-derived cytokines fails to diminish macrophage 12/15-lipoxygenase expression in vivo

IL-4 and IL-13 are the only known activators of 15-lipoxygenase (LO) expression in cultured macrophages. To determine whether these lymphocyte-derived cytokines regulate 15-LO expression in vivo, the abundance of the murine homologue (12/15-LO) was assessed in peritoneal macrophages from immune-deficient strains of mice. Macrophages were harvested from recombinase activator gene (RAG)-2-/- mice that do not develop mature lymphocytes and cannot secrete activation-dependent cytokines. Unexpectedly, 12/15-LO protein and activity were significantly increased in peritoneal macrophages from RAG-2-/- mice compared with strain-matched controls. This increase was related to phenotypic differences between cells from RAG-2+/+ and RAG-2-/- mice. After 3 h in culture, RAG-2+/+ macrophages were of two distinct sizes, with only the larger cells immunostaining for 12/15-LO. However, all RAG-2-/- cells were distributed in the large size range, and all were immunoreactive for the enzyme. The activation of 12/15-LO expression appears to be related to prolonged residence within the peritoneum, since there were fewer resident peritoneal macrophages in RAG-2-/- than in RAG-2+/+ mice, and newly recruited macrophages elicited by the administration of Sephacryl to RAG-2-/- mice did not immunostain for 12/15-LO. To determine whether 12/15-LO expression was due to IL-4 or IL-13 from nonlymphoid cells, the abundance of the enzyme was quantified in peritoneal macrophages from STAT6-/-mice that have attenuated responses to both cytokines. STAT6 deficiency did not influence the abundance of the protein in macrophages. Therefore, neither IL-4 nor IL-13 secretion is a requirement for macrophage 15-LO expression in vivo.

Efficacy of CI-1020, an endothelin-A receptor antagonist, in hypoxic pulmonary hypertension

We previously showed that CI-1020, an endothelin (ET)-A-selective receptor antagonist, dose-dependently blocked acute hypoxic pulmonary hypertension (PH) in rats. In this study we show that CI-1020 can reverse existing PH and prevent progression of right ventricular hypertrophy (RVH) in rats exposed to chronic hypoxia. Male Sprague-Dawley rats were exposed to 20 days of hypoxia (10% O2) with CI-1020 treatment (20 or 40 mg/kg/day) starting on day 10. On day 20 of hypoxia, the rats were instrumented under anesthesia with a pulmonary artery cannula and allowed to recover to consciousness before measurement of mean pulmonary arterial pressure (MPAP). Blood samples were then collected for plasma ET-1 measurements, the rats killed, and their hearts dissected, dried, and weighed. RV/LV + septum ratio (g/g) was used as an index of RVH (RVHi). Normoxic rats and rats exposed to hypoxia for only 10 days were also evaluated as controls. Normoxic rats had MPAPs of 13 +/- 1 mm Hg, plasma ET-1 levels of 2.1 +/- 0.1 pg/ml, and an average RVHi of 0.29 +/- 0.03. Rats exposed to 10 or 20 days of hypoxia had MPAPs of 33 +/- 2 and 44 +/- 0 mm Hg, plasma ET-1 levels of 4.2 +/- 0.8 and 4.6 +/- 0.8 pg/ml, and average RVHis of 0.47 +/- 0.05 and 0.52 +/- 0.03, respectively. In comparison, rats treated with CI-1020 had MPAPs that were 37% (20 mg/kg/day) and 44% (40 mg/kg/day) lower than untreated 20-day hypoxic rats. Furthermore, rats dosed with 40 mg/kg/day of CI-1020 had MPAPs that were significantly lower (24%) than control 10-day hypoxic rats, indicating a significant reversal of PH. Along with this reversal in PH, their average RVHi was 23% lower (p < 0.05) relative to untreated 20-day hypoxic rats.

Simple and efficient generation in vitro of nested deletions and inversions: Tn5 intramolecular transposition

We have exploited the intramolecular transposition preference of the Tn 5 in vitro transposition system to test its effectiveness as a tool for generation of nested families of deletions and inversions. A synthetic transposon was constructed containing an ori, an ampicillin resistance (Ampr) gene, a multi-cloning site (MCS) and two hyperactive end sequences. The donor DNA that adjoins the transposon contains a kanamycin resistance (Kanr) gene. Any Amprreplicating plasmid that has undergone a transposition event (Kans) will be targeted primarily to any insert in the MCS. Two different size targets were tested in the in vitro system. Synthetic transposon plasmids containing either target were incubated in the presence of purified transposase (Tnp) protein and transformed. Transposition frequencies (Ampr/Kans) for both targets were found to be 30-50%, of which >95% occur within the target sequence, in an apparently random manner. By a conservative estimate 10(5) or more deletions/inversions within a given segment of DNA can be expected from a single one-step 20 microl transposition reaction. These nested deletions can be used for structure-function analysis of proteins and for sequence analysis. The inversions provide nested sequencing templates of the opposite strand from the deletions.

Human apolipoprotein E accelerates microtubule polymerization in vitro

Apolipoprotein E (apoE) is a 34-kDa protein implicated in Alzheimer's disease (AD) that has recently been identified in neuronal cytoplasm. In cultured neurons, the two major isoforms of apoE (E3 and E4) differentially affect neurite extension, microtubule formation, and the ratio of polymerized to depolymerized tubulin. We therefore examined the effects of apoE3 and apoE4 on microtubule assembly in vitro. ApoE3 and apoE4 equally accelerated microtubule polymerization under conditions of slow microtubule assembly. Controls comprising apolipoprotein A1, bovine serum albumin, trypsin inhibitor, and boiled apoE had no effect, demonstrating specificity of the apoE effect. The ability of both apoE isoforms to accelerate microtubule assembly in vitro suggests that isoform-specific differences in neurite extension may result from differences in the uptake, intracytoplasmic transport, or metabolism of these isoforms.

A specific 15-lipoxygenase inhibitor limits the progression and monocyte-macrophage enrichment of hypercholesterolemia-induced atherosclerosis in the rabbit

Oxidant signalling and lipoprotein oxidation may play important roles in atherosclerotic lesion development. Given coincident localization of 15-lipoxygenase (15-LO), stereospecific products of 15-LO and epitopes of modified LDL in atherosclerotic lesions, we hypothesized that inhibition of 15-LO by PD146176, an inhibitor of 15-LO with an IC50 in cells or isolated enzyme of 0.5-0.8 microM, may limit atherosclerotic lesion development through regulation of monocyte-macrophage enrichment. Rabbits exposed to chronic endothelial denudation of the iliac-femoral artery were meal-fed a 0.25% cholesterol (C), 3% peanut oil (PNO), 3% coconut oil (CNO) diet twice daily with and without 175 mg/kg PD146176 for 12 weeks. In a second study, atherosclerotic lesions were pre-established in rabbits through chronic endothelial denudation and meal-fed a 0.5% C, 3% PNO, 3% CNO diet for 9 weeks and a 0% C/fat diet for 6 weeks prior to an 8 week administration of PD146176 at 175 mg/kg, q.d. Plasma total and lipoprotein cholesterol exposure were similar in control and PD146176-treated animals in both studies but PD146176 increased plasma triglyceride exposure 2- to 4-fold. Plasma PD146176 concentrations ranged from 99 to 214 ng/ml at 2 h post-dose. In the progression study, the iliac-femoral monocyte-macrophage area was reduced 71%, cross-sectional lesion area was unchanged and cholesteryl ester (CE) content was reduced 63%. In the regression study, size and macrophage content of iliac-femoral, fibrous plaque-like lesions were decreased 34%, CE content was reduced 19% and gross extent of thoracic aortic lesions were reduced 41%. We conclude that PD146176 can limit monocyte macrophage enrichment of atherosclerotic lesions and can attenuate development of fibrofoamy and fibrous plaque lesions in the absence of changes in plasma total or lipoprotein cholesterol concentrations.

The clinical profile of end-stage AIDS

The purpose of this study was to describe the clinical profile of end-stage AIDS in patients 12 months before death. A cross-sectional examination of HIV-infected patients who attended a public HIV outpatient clinic between 1990 and 1996 and who died was conducted. The prevalence and first-time acquisition of AIDS-defining conditions 12 months before death were evaluated. The AIDS-defining conditions with the highest percentages of first-time acquisition in the last 12 months of life were progressive multifocal leukoencephalopathy (100%), lymphoma (96%), dementia (78.6%), Mycobacterium avium complex (MAC) infection (74.0%), toxoplasmosis (72.6%), and cytomegalovirus (CMV) infection (69.6%). Of the concomitant conditions studied, those with the highest percentages of first-time acquisition in the last 12 months of life were CMV with MAC (99%) and CMV with wasting (88%). Patients who acquire these AIDS-defining conditions may be eligible to receive information about end-stage options, such as hospice care. However, administration of aggressive antiretroviral treatments, such as the protease inhibitors, may affect this profile in the future, as the majority of the patients in this study were receiving the standard antiretroviral treatments of the time, primarily zidovudine.