Abciximab in the treatment of acute myocardial infarction eligible for primary percutaneous transluminal coronary angioplasty. Results of the Glycoprotein Receptor Antagonist Patency Evaluation (GRAPE) pilot study

OBJECTIVES

We sought to study the effect of early infusion of abciximab on coronary patency before primary angioplasty in patients with acute myocardial infarction.

BACKGROUND

Glycoprotein IIb/IIIa antagonists have proved to be effective in reducing ischemic events associated with coronary angioplasty. The present study explores whether abciximab alone, without administration of thrombolytic therapy, may induce reperfusion in patients with acute myocardial infarction.

METHODS

In the Glycoprotein Receptor Antagonist Patency Evaluation pilot study 60 patients with less than 6 h signs and symptoms of acute myocardial infarction eligible for primary angioplasty received in the emergency room a bolus of abciximab 250 microg/kg followed by a 12-h infusion of 10 microg/min. All patients were also treated with an oral dose of 160 mg aspirin and 5,000 IU of heparin intravenously. As soon as possible a diagnostic angiography was performed to evaluate the patency of the infarct-related artery.

RESULTS

The median time between onset of symptoms and the administration of the abciximab bolus was 150 min (range 45 to 345), and the median time between abciximab bolus and first contrast injection in the infarct-related artery was 45 min (range 10 to 150). In 24 patients (40%, 95% confidence interval 28% to 52%) Thrombolysis in Myocardial Infarction (TIMI) flow grade 2 or 3 was observed at a median time of 45 min (range 10 to 150) after abciximab bolus; TIMI flow grade 3 was observed in 11 patients (18%, 95% confidence interval 9% to 28%). There was no difference in percentage of TIMI flow grade 2 or 3 between patients who received abciximab within 2.5 h after onset of symptoms or thereafter.

CONCLUSIONS

Abciximab therapy given in the emergency room in patients awaiting primary angioplasty is associated with full reperfusion (TIMI flow grade 3) in about 20% and with TIMI flow grade 2 or 3 in about 40% of the patients at a median time of 45 min. These figures are higher than those in primary angioplasty trials without such pretreatment. Randomized controlled trials of very early infusion of abciximab, either prehospital or in-hospital, in patients eligible for angioplasty are warranted.

Clinical and histopathological characteristics in relation to aetiological risk factors in cutaneous melanoma: a population-based study

In this population-based, case-control study from Sweden using data collected from 1988 to 1990, an increased risk of melanoma was associated with the number of sunburns, propensity to freckle, the number of raised naevi and a family history of melanoma. Furthermore, a decreased risk was associated with occupational sun exposure. The purpose of this study was to investigate whether different histopathological features of the melanoma and clinical factors were related to the different aetiological risk factor patterns. All the confirmed primary cutaneous melanomas (n = 366) were included in the study. Both univariate analyses with tests for interaction and multivariate analyses were performed. Patients with melanoma on the trunk and patients with thin melanomas had an excess of close relatives with a history of melanoma (odds ratios [ORs] = 2.7 and 2.3, respectively). A relationship was also seen between melanomas in younger persons and a family history of melanoma (OR = 2.6). The presence of raised naevi on the arm had a tendency to be closer related to melanoma of the nodular type (OR = 4.3) than melanoma of the superficial spreading type (OR = 1.6). Patients with outdoor occupations during summer had a decreased risk of developing melanoma on the extremities. Melanoma diagnosed in patients born before 1939 had an association with sunburns (OR = 1.9) and freckling (OR = 2.0), while melanomas in patients born in 1939 or later were related to a family history of melanoma (OR = 2.2). These results suggest that different histopathological and clinical features of melanoma are associated with different risk factor patterns, which may imply diverging tumour genesis.

Comparison of oral bambuterol and inhaled salmeterol in patients with symptomatic asthma and using inhaled corticosteroids

Salmeterol inhaled twice-daily is now being used more frequently as additional treatment in asthma insufficiently controlled by inhaled corticosteroids. We compared oral bambuterol in a dose of 20 mg taken once daily in the evening with inhaled salmeterol at 50 microgram taken twice daily in 126 asthmatic patients (60 bambuterol, 66 salmeterol) aged 18 to 74 yr who were treated for at least 4 wk with inhaled corticosteroids at a constant dose of 400 to 2,000 microgram/d or with oral corticosteroids at </= 20 mg/d. The patients were able to use a pressurized metered dose inhaler (pMDI) efficiently, and had an FEV1 of 40 to 85% of the predicted normal value. During a run-in period, patients had to show at least one nocturnal or early awakening caused by asthma symptoms that required rescue medication, and a >/= 15% overnight decrease in peak expiratory flow (PEF) on 3 of the preceding 7 d, in order to be randomized into this double-blind, double dummy, multicenter parallel group study (2-wk run-in period and 6 wk of treatment). There was no significant difference between bambuterol and salmeterol in morning change from baseline in PEF (p = 0.53). The median increases in morning PEF were 50 L/min for bambuterol and 55 L/min for salmeterol. Other variables (evening PEF, percent of overnight decrease in PEF, number of awakenings, percent of nights with an awakening, number of puffs of rescue medication, asthma symptoms during the day and night, and mean tremor score) also showed no significant difference between bambuterol and salmeterol. Both treatments, at the doses given, were well tolerated. Once-daily oral bambuterol is a convenient, effective, and less expensive alternative to twice-daily inhaled salmeterol for treating nocturnal asthma.

Immunologic proliferation marker Ki-S2 as prognostic indicator for lymph node-negative breast cancer

BACKGROUND

Proper treatment of lymph node-negative breast cancer depends on an accurate prognosis. To improve prognostic models for this disease, we evaluated whether an immunohistochemical marker for proliferating cells, Ki-S2 (a monoclonal antibody that binds to a 100-kd nuclear protein expressed in S, G2, and M phases of the cell cycle), is an accurate indicator of prognosis.

METHODS

We studied 371 Swedish women with lymph node-negative breast cancer; the median follow-up time was 95 months. The fraction of tumor cells in S phase was assessed by flow cytometry, and tumor cell proliferation was measured immunohistochemically with the monoclonal antibodies Ki-S2 and Ki-S5 (directed against the nuclear antigen Ki-67). A combined prognostic index was calculated on the basis of the S-phase fraction, progesterone receptor content, and tumor size.

RESULTS

In multivariate analyses that did or did not (263 and 332 observations, respectively) include the S-phase fraction and the combined prognostic index, the Ki-S2 labeling index (percentage of antibody-stained tumor cell nuclei) emerged as the most statistically significant predictor of overall survival, disease-specific survival, and disease-free survival (all two-sided P<.0001). In the risk group defined by a Ki-S2 labeling index of 10% or less, life expectancy was not statistically significantly different from that of age-matched women without breast cancer, whereas the group with a high Ki-S2 labeling index had an increased risk of mortality of up to 20-fold.

CONCLUSIONS

Cellular proliferation is a major determinant of the biologic behavior of breast cancer. Prognosis is apparently best indicated by the percentage of cells in S through M phases of the cell cycle. Measurement of the Ki-S2 labeling index of a tumor sample may improve a clinician's ability to make an accurate prognosis and to identify patients with a low risk of recurrence who may not need adjuvant therapy.

Familial and hereditary prostate cancer in southern Sweden. A population-based case-control study

The objectives of this study were to investigate the effect of family history on prostate cancer risk, to estimate the incidence of hereditary prostate cancer in southern Sweden and to assess the reliability of self-reported family history of prostate cancer. The study included consecutive prostate cancer patients and age-matched control subjects from a geographically defined population. The controls consisted of 1 male patient with malignant melanoma or non-Hodgkin's lymphoma and 1 male from the community per prostate cancer case. Family history was assessed with questionnaires, and diagnoses of fathers and brothers of cases were validated by the Southern Swedish Regional Tumour Registry. Among fathers and brothers whose names and birth dates were available, 56 (92%) of the 61 reported prostate cancer diagnoses were verified. Fifteen per cent of 356 cases and 5.0% of 712 controls reported at least 1 case of prostate cancer among their brothers or fathers, giving a relative risk of 3.2 (95% confidence interval 2.1-5.1). The relative risk increased with decreasing age at diagnosis of the patient. Based on the pedigree, 3.1% of the 356 patients were classified as having hereditary prostate cancer. This proportion was significantly higher among patients diagnosed before the age of 60 years (7.1%) than among older patients (2.2%). We conclude that there is a substantially increased risk of prostate cancer for sons and brothers of prostate cancer patients. The risk increases with decreasing age at diagnosis of the patient as an effect of a higher prevalence of hereditary prostate among early onset cases. Furthermore, we found self-reported family history of prostate cancer to be a valid estimate of the true incidence of prostate cancer in fathers and brothers of men with prostate cancer.

Somatic genetic alterations in BRCA2-associated and sporadic male breast cancer

The genetic changes underlying the development and progression of male breast cancer are poorly understood. Germline BRCA2 mutations account for a significant part of male breast cancer, but the majority of patients lack a known inherited predisposition. We recently demonstrated that the progression of breast cancer in female carriers of a germline BRCA1 or BRCA2 mutation follows specific genetic pathways, distinct from each other and from sporadic breast cancer. In the present study, we performed a genome-wide survey by comparative genomic hybridization (CGH) of somatic genetic aberrations in 26 male breast cancers, including five tumors from BRCA2 mutation carriers. BRCA2 tumors exhibited a significantly higher number of chromosomal aberrations than sporadic tumors. The most common alterations in sporadic male breast cancer were +1q (38%), +8q (33%), +17q (33%), -13q (29%), and -8p (24%). In tumors from BRCA2 mutation carriers, the five most common genetic changes were +8q (100%), +20q (100%), +17q (80%), -13q (80%), and -6q (60%). The CGH results in these two groups of male breast cancers are almost identical to those identified in the corresponding sporadic and BRCA2-associated female breast cancers. The results suggest that despite substantial hormonal differences between females and males, similar genetic changes are selected for during tumor progression. Furthermore, the presence of a highly penetrant germline BRCA2 mutation apparently leads to a characteristic somatic tumor progression pathway, again shared between affected male and female mutation carriers.

Guidelines for follow-up of women at high risk for inherited breast cancer: consensus statement from the Biomed 2 Demonstration Programme on Inherited Breast Cancer

Protocols for activity aiming at early diagnosis and treatment of inherited breast or breast-ovarian cancer have been reported. Available reports on outcome of such programmes are considered here. It is concluded that the ongoing activities should continue with minor modifications. Direct evidence of a survival benefit from breast and ovarian screening is not yet available. On the basis of expert opinion and preliminary results from intervention programmes indicating good detection rates for early breast cancers and 5-year survival concordant with early diagnosis, we propose that women at high risk for inherited breast cancer be offered genetic counselling, education in ‘breast awareness’ and annual mammography and clinical expert examination from around 30 years of age. Mammography every second year may be sufficient from 60 years on. BRCA1 mutation carriers may benefit from more frequent examinations and cancer risk may be reduced by oophorectomy before 40–50 years of age. We strongly advocate that all activities should be organized as multicentre studies subjected to continuous evaluation to measure the effects of the interventions on long-term mortality, to match management options more precisely to individual risks and to prepare the ground for studies on chemoprevention.

Correlation between p53, c-erbB-2, and topoisomerase II alpha expression, DNA ploidy, hormonal receptor status and proliferation in 356 node-negative breast carcinomas: prognostic implications

Various new prognostic indicators have been identified for mammary carcinomas, but the issue of their significance remains unsettled. The prognostic impact of p53, c-erbB-2, and topoisomerase II alpha expression was investigated in relation to standard prognostic factors for carcinomas of the breast and to the tumour cell growth fraction. Paraffin-embedded specimens of 356 node-negative infiltrating ductal carcinomas were stained immunohistochemically using a polyclonal antiserum to c-erbB-2, and the monoclonal antibodies DO-1 (p53), Ki-S4 (topoisomerase II alpha), and Ki-S5 (Ki-67). The patients were followed for a median duration of 99 months. Both p53 and c-erbB-2 were significantly associated with high tumour grade, large tumour size, DNA aneuploidy, lack of steroid hormone receptors, young age, and increased topoisomerase II alpha and Ki-67 expression levels. The correlation of p53 and c-erbB-2 was not significant. Topoisomerase II alpha and Ki-67 scores closely paralleled each other, indicating that both reflect the proliferative activity of tumour cells. A univariate analysis of overall (OS), specific (SS), and disease-free survival (DFS) revealed all the above-mentioned parameters to be statistically significant except patient age, which was relevant only to overall survival. Multivariate analysis with inclusion of all covariates selected tumour size and proliferation (topoisomerase II alpha and Ki-67) indices as independent predictors of survival in all three models. No additional information was gained by p53 or c-erbB-2. It is concluded that the proliferative activity, as assessed by topoisomerase II alpha or Ki-67 immunostaining, is the most useful indicator of breast cancer prognosis, except for tumour size.

Cartilage oligomeric matrix protein (COMP)-induced arthritis in rats

In rheumatoid arthritis peripheral cartilaginous joints are inflamed and eroded. One driving factor may be an immune response towards proteins in the cartilage. Here it is shown that cartilage oligomeric matrix protein (COMP), expressed specifically in cartilage, is arthritogenic in the rat. Both native and denatured rat COMP induced severe arthritis in selected rat strains. The arthritis occurred only in peripheral joints which were attacked by an erosive inflammatory process similar to that seen in the human disease. The disease was self-limited and no permanent destruction of joints was seen macroscopically. Disease development appeared to be dependent on an immune response to autologous (rat) COMP and not on cross-reactivity to other cartilage rat collagens (types II, IX and XI). The disease and the immune response to COMP were genetically controlled by the MHC; the RT1u and RT1l haplotypes were more susceptible than the a, c, d, f and n haplotypes. Both LEW and E3 gene backgrounds were highly permissive for disease induction. These findings suggest that the induction of arthritis with rat COMP represents a unique pathogenesis which is controlled by different genes compared with collagen-induced arthritis or adjuvant-induced arthritis.

Oral contraceptives and the risk of hereditary ovarian cancer. Hereditary Ovarian Cancer Clinical Study Group

BACKGROUND

Women with mutations in either the BRCA1 or the BRCA2 gene have a high lifetime risk of ovarian cancer. Oral contraceptives protect against ovarian cancer in general, but it is not known whether they also protect against hereditary forms of ovarian cancer.

METHODS

We enrolled 207 women with hereditary ovarian cancer and 161 of their sisters as controls in a case-control study. All the patients carried a pathogenic mutation in either BRCA1 (179 women) or BRCA2 (28 women). The control women were enrolled regardless of whether or not they had either mutation. Lifetime histories of oral-contraceptive use were obtained by interview or by written questionnaire and were compared between patients and control women, after adjustment for year of birth and parity.

RESULTS

The adjusted odds ratio for ovarian cancer associated with any past use of oral contraceptives was 0.5 (95 percent confidence interval, 0.3 to 0.8). The risk decreased with increasing duration of use (P for trend, <0.001); use for six or more years was associated with a 60 percent reduction in risk. Oral-contraceptive use protected against ovarian cancer both for carriers of the BRCA1 mutation (odds ratio, 0.5; 95 percent confidence interval, 0.3 to 0.9) and for carriers of the BRCA2 mutation (odds ratio, 0.4; 95 percent confidence interval, 0.2 to 1.1).

CONCLUSIONS

Oral-contraceptive use may reduce the risk of ovarian cancer in women with pathogenic mutations in the BRCA1 or BRCA2 gene.

Cartilage oligomeric matrix protein shows high affinity zinc-dependent interaction with triple helical collagen

Cartilage and tendon extracellular matrices are composed of collagens, proteoglycans, and a number of noncollagenous proteins. Cartilage oligomeric matrix protein (COMP) is a prominent such protein, structurally related to the thrombospondins. We found that native COMP binds to collagen I/II and procollagen I/II and that the interaction is dependent on the divalent cations Zn2+ or Ni2+, whereas Ca2+, Mg2+, and Mn2+ did not promote binding. Using a solid phase assay, Scatchard analysis identified one class of binding site with a dissociation constant (Kd) close to 1.5 nM in the presence of Zn2+. The results were confirmed by studies using surface plasmon resonance. Furthermore, metal chelate chromatography demonstrated that COMP bound Zn2+ and Ni2+. Electron microscopy showed that the interaction occurred at four defined sites on the 300-nm collagen and procollagen molecules. Two were located close to each end, and two at 126 and 206 nm, respectively, from the C-terminal. COMP interacted via its C-terminal globular domain and significantly only in the presence of Zn2+.

Purification and characterization of a protein binding to the SP6 kappa promoter. A potential role for CArG-box binding factor-A in kappa transcription

A protein interacting with an A-T-rich region that is a positive control element within the SP6 kappa promoter was purified and identified as CArG-box binding factor-A. The purified protein was shown to interact specifically with the coding strand of single-stranded DNA and, with lower affinity, with double-stranded DNA. A mutation that inhibited binding of the protein to the A-T-rich region also aborted the transcriptional stimulatory effect of the region. Two Ets proteins, PU.1 and elf-1, that have previously been shown to bind to an adjacent DNA element were shown to physically interact with CArG-box binding factor-A. An antiserum raised against the protein recognized two different forms indicating either that different splice-forms of CArG-box binding factor-A are expressed, or that the protein is subject to post-translational modification.

A PET study of D2 dopamine receptor density at different phases of the menstrual cycle

Behavioral and biochemical studies in animals indicate that central dopaminergic neurotransmission may be modulated by sex steroids. This may be the mechanism underlying the suggested association between estrogen and schizophrenia. The aim was to examine if different levels of sex steroids during the menstrual cycle are associated with variations in D2 dopamine receptor density as measured with positron emission tomography (PET) and [11C]raclopride. Five healthy women were examined, one during two subsequent follicular phases and four during two different phases of their menstrual cycle. In none of the women did the difference in putamen to cerebellum (P/C) ratios (-11 to 10%) exceed the difference in P/C ratios previously reported in test-retest analyses in men (-11 to 9%). The findings do not support the conclusion that there is a menstrual-cycle-dependent variation in D2 receptor density detectable with single PET examinations and [11C]raclopride. Furthermore, a stable P/C ratio throughout the menstrual cycle indicated a stable D2 receptor occupancy in schizophrenic women treated with antipsychotic drugs. Repeated PET examinations of schizophrenic women known to deteriorate during particular phases of their menstrual cycle may further contribute to our understanding of the association between schizophrenia and sex steroids.

Steroid receptors in hereditary breast carcinomas associated with BRCA1 or BRCA2 mutations or unknown susceptibility genes

BACKGROUND

The expression of steroid receptors is a common feature of both male and female breast carcinomas and is also one of the most important prognostic factors for patients with this disease. Steroid receptor levels in BRCA1-related breast carcinoma have reportedly been low. Little data on steroid receptor levels have been reported with regard to BRCA2.

METHODS

Steroid receptor levels were analyzed in 27 breast carcinomas associated with BRCA1 mutations, 14 associated with BRCA2 mutations, and 32 from individuals who had hereditary breast carcinoma but no detectable mutations of either BRCA1 or BRCA2. Breast carcinomas from 32 consecutive male patients, 6 of whom had mutations of BRCA2, were also examined for steroid receptors. Estrogen receptor (ER) and progesterone receptor (PgR) analyses were performed with radioligand or enzyme immunoassay techniques on tumor cytosol preparations. Germline mutation screening and detection were performed using the protein truncation test, single strand conformation polymorphism, and direct sequencing on DNA from normal tissue.

RESULTS

The BRCA1-related tumors expressed significantly lower levels of ER than tumors from the other hereditary groups. The PgR levels were significantly lower in the BRCA1-related cases than in the hereditary cases not related to BRCA1 or BRCA2, but not significantly lower than in the BRCA2-related cases. Fourteen of 32 (44%) of the hereditary tumors not related to BRCA1 or BRCA2 had PgR levels exceeding 100 fmol/mg of protein. The tumors from male patients with BRCA2-related disease did not have receptor levels that differed from those in non-BRCA2-related tumors.

CONCLUSIONS

BRCA1- and BRCA2-related breast tumors were distinct in their expression of steroid receptors. Moreover, a subgroup of tumors not related to BRCA1 or BRCA2 manifested a strongly positive PgR phenotype rarely seen in BRCA1- and BRCA2-related tumors. These characteristics may be of relevance to the treatment and follow-up of high risk individuals in these families and may help identify a homogeneous category of hereditary breast carcinomas not related to BRCA1 or BRCA2 in which new susceptibility genes may be sought.

Insulin-like growth factor-1 in relation to adult weight and birth weight in healthy nulliparous women

OBJECTIVE

To study the relationships between plasma insulin-like growth factor-1 (IGF-1) concentrations and birth weight, current weight and other constitutional factors among healthy, nulliparous women aged 19-25 years.

DESIGN AND METHODS

Forty healthy female university students aged 19-25 years volunteered for this study. They had never been pregnant and were not using oral contraceptives (OCs). Blood samples were drawn both in the follicular and luteal cycle phases (08:00-10:00 h) and weight, height, and waist-hip ratio were measured at the same time by one person (H.J). Information regarding age, birth weight, OC use, etc. was obtained from a questionnaire filled out by the women. Plasma IGF-1 concentrations were analyzed by radio immunoassay.

RESULTS

In a multivariate model including birth weight, current weight and age, IGF-1 was significantly inversely associated with birth weight in both cycle phases, while current weight was positively associated with IGF-1 in both cycle phases although only significantly so in the follicular phase. IGF-1 concentrations in both cycle phases showed a non-significant decrease with age.

CONCLUSION

In this group of 19-25-year-old healthy nulliparous women IGF-1 displayed a significant inverse association with birth weight in both cycle phases given that the current weight was adjusted for, while current weight was positively related to IGF-1 concentrations.

Relapse rate, renal survival, and cancer morbidity in patients with Wegener's granulomatosis or microscopic polyangiitis with renal involvement

Wegener's granulomatosis (WG) and microscopic polyangiitis (MPA) are both frequently associated with antineutrophil cytoplasmic autoantibodies (ANCA). Immunosuppressive treatment has dramatically improved outcome for these patients, but today we have to deal with the problems of relapses, cases refractory to treatment, and long-term side effects of therapy. This study comprises a consecutive series of 123 patients with WG (n=56) or MPA (n=67) with biopsy-confirmed renal involvement, followed up for a median of 55 mo (range, 0.1 to 273.2 mo). ANCA was detected by enzyme-linked immunosorbent assay in 97% of patients. Nearly half of the patients (46%) relapsed. There was no statistically significant difference in overall relapse rate according to type of ANCA. Renal survival was 78% in patients alive at the end of follow-up. Three variables seemed important for renal survival: serum creatinine, the titer of proteinase 3-ANCA measured by capture enzyme-linked immunosorbent assay, and B thrombocyte count, at time of referral. Cancer incidence data were obtained from the population-based South Swedish Regional Tumor Registry. Standardized morbidity ratio was calculated using expected values from the health care region. We found an 11-fold increase in risk for bladder cancer in patients treated with cyclophosphamide for at least 12 mo. Skin carcinoma had the strongest relationship with azathioprine use for at least 12 mo and with corticosteroid therapy for at least 48 mo. In addition, four patients developed myelodysplastic syndrome and five had carcinoma in situ of the skin. Because the therapeutic regimen used today is not efficient enough to prevent relapses and is associated with a host of side effects, of which the risk for cancer is by far the most important, improved therapy and medical care are needed for patients with WG and MPA.

[carbonyl-11C]Desmethyl-WAY-100635 (DWAY) is a potent and selective radioligand for central 5-HT1A receptors in vitro and in vivo

[carbonyl-11C]Desmethyl-WAY-100635 (DWAY) is possibly a low-level metabolite appearing in plasma after intravenous administration of [carbonyl-11C]WAY-100635 to human subjects for positron emission tomographic (PET) imaging of brain 5-HT1A receptors. In this study we set out to assess the ability of DWAY to enter brain in vivo and to elucidate its possible interaction with 5-HT1A receptors. Desmethyl-WAY-100635 was labelled efficiently with carbon-11 (t1/2 = 20.4 min) in high specific radioactivity by reaction of its descyclohexanecarbonyl analogue with [carbonyl-11C]cyclohexanecarbonyl chloride. The product was separated in high radiochemical purity by high-performance liquid chromatography (HPLC) and formulated for intravenous injection. Rats were injected intravenously with DWAY, sacrificed at known times and dissected to establish radioactivity content in brain tissues. At 60 min after injection, the ratios of radioactivity concentration in each brain region to that in cerebellum correlated with previous in vitro and in vivo measures of 5-HT1A receptor density. The highest ratio was about 22 in hippocampus. Radioactivity cleared rapidly from plasma; HPLC analysis revealed that DWAY represented 55% of the radioactivity in plasma at 5 min and 33% at 30 min. Only polar radioactive metabolites were detected. Subsequently, a cynomolgus monkey was injected intravenously with DWAY and examined by PET. Maximal whole brain uptake of radioactivity was 5.7% of the administered dose at 5 min after injection. The image acquired between 9 and 90 min showed high radioactivity uptake in brain regions rich in 5-HT1A receptors (e.g. frontal cortex and neocortex), moderate uptake in raphe nuclei and low uptake in cerebellum. A transient equilibrium was achieved in cortical regions at about 60 min, when the ratio of radioactivity concentration in frontal cortex to that in cerebellum reached 6. The corresponding ratio for raphe nuclei was about 3. Radioactive metabolites appeared rapidly in plasma, but these were all more polar than DWAY, which represented 52% of the radioactivity in plasma at 4 min and 20% at 55 min. In a second PET experiment, in which a cynomolgus monkey was pretreated with the selective 5-HT1A receptor antagonist, WAY-100635, at 25 min before DWAY injection, radioactivity in all brain regions was reduced to that in cerebellum. Autoradiography of post mortem human brain cryosections after incubation with DWAY successfully delineated 5-HT1A receptor distribution. Receptor-specific binding was eliminated in the presence of the selective 5-HT1A receptor agonist, 8-OH-DPAT [(+/-)-8-hydroxy-2-dipropylaminotetralin]. These findings show that: (a) intravenously administered DWAY is well able to penetrate brain in rat and monkey, (b) DWAY is a highly effective radioligand for brain 5-HT1A receptors in rat and monkey in vivo and for human brain in vitro, and (c) the metabolism and kinetics of DWAY appear favourable to successful biomathematical modelling of acquired PET data. Thus, DWAY warrants further evaluation as a radioligand for PET studies of 5-HT1A receptors in human brain.

Hemin binding and oxidation of lipoproteins in serum: mechanisms and effect on the interaction of LDL with human macrophages

Most models of lipoprotein oxidation by free radicals have excluded macromolecular plasma components from the system. This limits their biological significance because oxidation of lipoproteins appears to occur in the intima in the presence of a plasma ultrafiltrate. Hemin, a product of in vivo hemoglobin degradation, binds and oxidizes purified lipoproteins. However, it is not known whether this occurs in the presence of plasma components that may sequester hemin. We found that hemin in serum diluted to protein levels of the extracellular fluid (10-30%) binds to low and high density lipoproteins (LDL, HDL) with association constants in the nmol/L range. In the presence of H2O2, hemin oxidizes both lipoproteins in diluted serum with formation of conjugated dienes, thiobarbituric acid reacting substances, and F2-isoprostanes. This appeared to be caused by the high affinity of hemin with LDL and by the Fe3+ liberated that remains associated with the particles after hemin is degraded. Spectrophotometric and fluorescence experiments and electrophoresis of porphyrins complex with LDL indicated that the heme ring is buried in the lipoprotein surface-monolayer with the carboxylic groups in contact with positive regions of the protein and the solvent. Human macrophages associated and degraded 3- to 4-times more hemin-oxidized LDL in diluted serum than native LDL. It is possible then that at sites of LDL, accumulation in the extracellular intima, hemin and H2O2 production could cause oxidation with potential atherogenic consequences for cellular lipoprotein processing. This may occur even when other macromolecules of the extracellular fluid are present.

BRCA2 germ-line mutations are frequent in male breast cancer patients without a family history of the disease

Breast cancer is a rare disease in men, affecting less than 0.1% of the male population. Two heritable gene defects have been associated with a predisposition to male breast cancer development, ie., germ-line mutations in the breast cancer susceptibility gene BRCA2 and the androgen receptor (AR) gene. In this study, the entire coding regions of BRCA2 and AR were screened for mutations in 34 consecutive male breast cancer patients. Five different truncating BRCA2 mutations were identified in 7 (21%) of the 34 cases, with all mutations being of germ-line origin. Three of the mutated cases carried the same mutation (4186delG), which has been found earlier in two Swedish families with multiple female breast cancer cases. Haplotype analysis supported a common ancestry of 4186delG. One mutation, 6503delTT, was found in a male carrying also a previously identified COOH-terminal polymorphic stop codon (Lys3326ter). No differences were seen between mutation carriers and noncarriers with respect to clinical stage and estrogen or progesterone receptor status. Mutation carriers tended to be younger at diagnosis. No germ-line AR mutations were found in the present material, but the number of AR polyglutamine repeats tended to be lower among mutation carriers. Most surprisingly, only one of the seven BRCA2 mutation carriers had a positive family history of breast cancer, suggesting a lower penetrance of some BRCA2 mutations or an influence of modifying factors for disease development in males and females. The present study implies that approximately one-fifth of all male breast cancer cases in the Swedish population are due to germ-line BRCA2 mutations.

Increased serum levels of cartilage oligomeric matrix protein in chronic erosive arthritis in rats

OBJECTIVE

To investigate the utility of serum cartilage oligomeric matrix protein (COMP) for disease monitoring in rats with chronic pristane-induced arthritis, and to examine the influence of age, sex, and genes on COMP concentrations in rat serum.

METHODS

Serum COMP levels were quantified by immunoassay. Sera were obtained from DA, E3, and (E3 x DA)F1 rats each week between the ages of 4 and 30 weeks. The (E3 x DA)F2 (second generation after intercrossing) rats were injected intradermally with the synthetic oil pristane. Arthritis was monitored by a macroscopic scoring system, and serum levels of COMP were measured on days 6, 35, and 49 after immunization.

RESULTS

Serum levels of COMP decreased during growth, and reached a plateau after the age of 12 weeks. The DA rats had higher COMP levels than the E3 rats, and the (E3 x DA)F1 rats had intermediate levels. No differences were observed in these levels when the rats were grouped by sex. Arthritic (E3 x DA)F2 rats had increased serum concentrations of COMP on days 35 and 49 after pristane injection (P < 0.0001 versus the nonarthritic animals). COMP levels correlated with the severity of macroscopically detectable arthritis at both time points (r > 0.9). Rats with a chronic disease course were distinguished by higher serum concentrations of COMP during the acute stage than animals with similar clinical scores but with resolving arthritis (P < 0.01).

CONCLUSION

Serum analyses of COMP offer promise for monitoring tissue involvement in experimental arthritis. Such analyses should be useful for monitoring therapeutic interventions aimed at retarding tissue destruction as well as for studies of the genetically determined regulation of COMP turnover and susceptibility to arthritis. The application of molecular marker measurements to experimental arthritis offers a new possibility for verifying the utility of such measurements in human arthritis.

BRCA1-positive patients are small for gestational age compared with their unaffected relatives

The BRCA1 gene is thought to exert its main function early in life. We, therefore, studied the effects of BRCA1 mutations on birth weight and birth length. This was carried out by comparing 33 women with and without mutations. Birth weight and length were obtained from a self-administered questionnaire. BRCA1 mutations carriers had a significantly lower birth weight (P = 0.0041) compared with non-carriers, after adjustment for gestational age. They were also significantly shorter at birth compared with their unaffected relatives (P = 0.0060), after adjustment for gestational age. The BRCA1 gene thus seems to influence the carriers in utero. The findings could imply that humans heterozygotic for the BRCA1 mutations may be influenced by the mutations during development in utero.