Pharmacogenetic and metabolite measurements are associated with clinical status in patients with rheumatoid arthritis treated with methotrexate: results of a multicentred cross sectional observational study

OBJECTIVE

To investigate the contribution of red blood cell (RBC) methotrexate polyglutamates (MTX PGs), RBC folate polyglutamates (folate PGs), and a pharmacogenetic index to the clinical status of patients with rheumatoid arthritis treated with MTX.

METHODS

226 adult patients treated with weekly MTX for more than 3 months were enrolled at three sites in a multicentred cross sectional observational study. Clinical status was assessed by the number of joint counts, physician's global assessment of disease activity, and a modified Health Assessment Questionnaire (mHAQ). RBC MTX PG and folate PG metabolite levels were measured by high performance liquid chromatography fluorometry and radioassay, respectively. A composite pharmacogenetic index comprising low penetrance genetic polymorphisms in reduced folate carrier (RFC-1 G80A), AICAR transformylase (ATIC C347G), and thymidylate synthase (TSER*2/*3) was calculated. Statistical analyses were by multivariate linear regression with clinical measures as dependent variables and metabolite levels and the pharmacogenetic index as independent variables after adjustment for other covariates.

RESULTS

Multivariate analysis showed that lower RBC MTX PG levels (median 40 nmol/l) and a lower pharmacogenetic index (median 2) were associated with a higher number of joint counts, higher disease activity, and higher mHAQ (p<0.09). Multivariate analysis also established that higher RBC folate PG levels (median 1062 nmol/l) were associated with a higher number of tender and swollen joints after adjustment for RBC MTX PG levels and the pharmacogenetic index (p<0.05).

CONCLUSION

Pharmacogenetic and metabolite measurements may be useful in optimising MTX treatment. Prospective studies are warranted to investigate the predictive value of these markers for MTX efficacy.

Deep vein thrombosis associated with distension of the urinary bladder due to benign prostatic hypertrophy--a case report

A 76-year-old man was admitted with a first episode of deep vein thrombosis (DVT) of his left leg. It was associated with a distended urinary bladder, due to benign prostatic hypertrophy. Screening for malignancy was negative. Laboratory testing revealed protein S deficiency. Although a distended bladder may induce venous stasis, it is not a proven risk factor for DVT. Clinical expression possibly depends on the concomitance of other risk factors, such as inherited or acquired thrombophilic defects. However, it is also possible that the association of a distended bladder with DVT of a lower limb has not been recognised yet. As a distended bladder is rather common in elderly men, a proper study is warranted to estimate the prevalence of associated DVT.

[The haematogenous reproduction theory of Aristotle]

From the very beginning, man has been fascinated by the continuous coming into being of new life on Earth. Archeological and anthropological data indicate that in prehistoric times, reproduction was attributed to a fertility goddess that required no sperm for this purpose. In the early historical Middle East it was believed that a godly being brought about pregnancy by using male and female semen. It was the merit of the Greek philosophers of the 6th-3rd century B.C. to realize that reproduction was governed by natural laws. Several theories were developed to understand how reproduction could occur. The haematogenous theory of reproduction, developed by Aristotle, has received the most attention. The essence of this theory is that the male sperm, with a haematogenous origin, causes the development of an embryo from menstrual blood present in the female uterus. The theory survived about 2000 years, with modifications, and was also introduced into Christianity. It was only about 150 years ago that the reproduction theory based on hypotheses was changed into a reproduction science based on facts.

Xylem water content and wood density in spruce and oak trees detected by high-resolution computed tomography

Elucidation of the mechanisms involved in long-distance water transport in trees requires knowledge of the water distribution within the sapwood and heartwood of the stem as well as of the earlywood and latewood of an annual ring. X-ray computed tomography is a powerful tool for measuring density distributions and water contents in the xylem with high spatial resolution. Ten- to 20-year-old spruce (Picea abies L. KARST.) and oak (Quercus robur) trees grown in the field were used throughout the experiments. Stem and branch discs were collected from different tree heights, immediately deep frozen, and used for the tomographic determinations of spatial water distributions. Results are presented for single-tree individuals, demonstrating heartwood and sapwood distribution throughout their entire length as well as the water relations in single annual rings of both types of wood. Tree rings of the sapwood show steep water gradients from latewood to earlywood, whereas those of the heartwood reflect water deficiency in both species. Although only the latest two annual rings of the ringporous species are generally assumed to transport water, we found similar amounts of water and no tyloses in all rings of the oak sapwood, which indicates that at least water storage is important in the whole sapwood.

Starting a disease modifying antirheumatic drug or a biologic agent in rheumatoid arthritis: standards of practice for RA treatment

Our aim was to investigate the practices and standards by which disease modifying antirheumatic drugs (DMARD) and biologics are and have been prescribed. We reviewed the literature and examined data from patients with rheumatoid arthritis (RA) participating in a national cohort: the National Data Bank for Rheumatic Diseases (NDB). Four pathways for DMARD prescription were identified: (1) A time-based pyramidal approach (the RA pyramid); (2) a severity-based pyramid in which the most effective treatment is given to those with more active disease; (3) a cost-based pathway in which the primary goal is cost containment--this pathway intertwines with the severity-based pathway; and (4) a patient preference pathway where treatment is geared to patient needs and wishes regardless of severity. Data show that the time-based and severity-based pathways are not generally used in contemporary expert practice, and that patients with all degrees of severity and disease duration are receiving DMARD and biologic treatment. With the abandonment of the pyramid and the development of effective therapy, rheumatic disease care has swung away from the imperative of time and severity-based treatment to the imperative of care based on patient preference. It is the standard of practice to treat patients with mild and early disease with aggressive therapy, with the goal of limiting subsequent damage and retarding progression, and with the realistic purpose of relieving symptoms. The standard may at times be in conflict with the goals of insurers, but there is no legitimate medical reason for such limitations.

Syndromic validity of apathy in Alzheimer's disease

OBJECTIVE

The study examined the usefulness and clinical correlates of specific diagnostic criteria for apathy in Alzheimer's disease. Whereas apathy is a frequent behavioral change in patients with Alzheimer's disease, the lack of standardized diagnostic criteria may explain the wide discrepancies in estimates of the frequency and demographic and clinical correlates of apathy.

METHOD

A consecutive series of 319 patients who met the criteria for probable Alzheimer's disease established by the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association, 117 patients who met the DSM-IV criteria for depression without dementia, and 36 healthy individuals were assessed with a structured psychiatric interview. On the basis of modified Marin's criteria for apathy, they were classified into groups with or without apathy.

RESULTS

Apathy was diagnosed in 37% of the 319 Alzheimer's disease patients, compared to none of the healthy comparison subjects. In 24% of the Alzheimer's disease sample, apathy coexisted with either dysthymic disorder or major depressive disorder, whereas 13% had apathy without depression. Apathy was diagnosed in 32% of the depressed nondemented patients, mostly in those with major depressive disorder. Apathy in Alzheimer's disease was significantly associated with severe impairments in activities of daily living and cognitive functions, older age, and poor awareness of behavioral and cognitive changes.

CONCLUSIONS

This study provides partial validation of specific clinical criteria for apathy in Alzheimer's disease.

The specificity of depressive symptoms in patients with Alzheimer's disease

OBJECTIVE

This study assessed the specificity of depressive symptoms in patients with Alzheimer's disease and examined the discrepancies between patient and caregiver symptom reports.

METHOD

The study group was composed of a series of 233 patients with Alzheimer's disease, 47 patients with depression but without dementia, and 20 healthy comparison subjects; the latter two groups were comparable in age with the patients with Alzheimer's disease. The patients and comparison subjects received a comprehensive psychiatric evaluation, which included administration of the Hamilton Depression Rating Scale and the Structured Clinical Interview for DSM-IV.

RESULTS

Patients with Alzheimer's disease with a score of 2 or higher on the "depressed mood" item of the Hamilton depression scale, as scored by their respective caregivers, comprised a group with depressed mood (N=92), whereas patients who scored 0 on this item comprised a group without depressed mood (N=62). A statistical comparison of the scores on the remaining Hamilton depression scale items (2-16) between the Alzheimer's disease patients with and without depressed mood revealed significant differences on all items, except "loss of appetite." However, there were no significant differences on any single Hamilton depression scale item between the Alzheimer's disease patients without depressed mood and the age-comparable healthy comparison subjects.

CONCLUSIONS

Depressive symptoms are not widespread among patients with Alzheimer's disease but are significantly related to an underlying depressed mood. Patients with Alzheimer's disease may not be fully aware of the extent of their depressive symptoms.

From prostaglandin replacement to specific COX-2 inhibition: a critical appraisal

Nonsteroidal antiinflammatory drugs (NSAID) are among the most widely prescribed medications worldwide. While these agents are efficacious for the relief of both pain and the signs and symptoms of inflammation, the use of traditional NSAID is associated with a high prevalence of toxic events. It is estimated that 2-4% of traditional NSAID users will have a serious adverse gastrointestinal (GI) event per year, with a point prevalence of GI ulcers at any given time of 10-30%. The mortality rate associated with these NSAID is one of the highest attributed to the use of any agent. Prostaglandin replacement with misoprostol has been shown to significantly reduce the incidence of serious GI toxicity related to the use of conventional NSAID. All conventional NSAID inhibit both cyclooxygenase-1 (COX-1) and COX-2 enzymes. As COX-1 is constitutively expressed in many tissues and contributes to the maintenance of the normal physiologic state in the GI tract, the kidney, and platelets, an agent that specifically inhibits COX-2, an inducible enzyme associated with the inflammatory response, would be highly desirable. Specific COX-2 inhibition would have the advantage of improving the signs and symptoms of inflammation, while avoiding the possibly significant toxicity of traditional NSAID. This article describes the biology of eicosanoids and the effects of NSAID, the toxicity profile of conventional NSAID, and the rationale for the use of gastroprotective agents or agents that specifically inhibit the COX-2 isozyme.

First Mass-resolved Measurement of High-Energy Cosmic-Ray Antiprotons

We report new results for the cosmic-ray antiproton-to-proton ratio from 3 to 50 GeV at the top of the atmosphere. These results represent the first measurements, on an event-by-event basis, of mass-resolved antiprotons above 18 GeV. The results were obtained with the NMSU-WIZARD/CAPRICE98 balloon-borne magnet spectrometer equipped with a gas-RICH (Ring-Imaging Cerenkov) counter and a silicon-tungsten imaging calorimeter. The RICH detector was the first ever flown that is capable of identifying charge-one particles at energies above 5 GeV. The spectrometer was flown on 1998 May 28-29 from Fort Sumner, New Mexico. The measured p&d1;/p ratio is in agreement with a pure secondary interstellar production.

A qualitative investigation of women's perceptions of premenstrual syndrome: implications for general practitioners

BACKGROUND

Many women consult general practitioners each year, seeking treatment for premenstrual syndrome. This qualitative study presents evidence of women's own perceptions of this problem, which may assist in the provision of individualized health care.

AIM

To explore women's constructions of premenstrual syndrome using grounded analysis.

METHOD

A qualitative, semi-structured interview study carried out in Northern Ireland. Thirteen women were interviewed individually. Thereafter, 33 women participated in group discussions. Five health visitors then commented individually on the findings.

RESULTS

Seven themes emerged from the analysis. These themes suggested that women tend to view the menstrual cycle holistically and that premenstrual syndrome is regarded as debilitating by only a small minority of women. Participants indicated an awareness of the intra- and inter-personal variability of menstrual experience. They were ambivalent about menstruation, viewing it as natural but, at the same time, unnatural in terms of day-to-day existence. Talking to other women served two functions, first by providing a yardstick against which to evaluate their own experiences, and secondly by providing support and advice. In contrast, women tended to talk about menstruation only to selected men, mainly partners, primarily in the interests of educating them. Women viewed menstruation as potentially disempowering by virtue of its uncontrollability, and felt that both a positive attitude and the use of a range of remedies were important for women wishing to become empowered with respect to this aspect of their lives.

CONCLUSIONS

Women's own constructions of premenstrual syndrome differ markedly from those as presented in medical textbooks and research literature: secondary sources that have significantly impacted upon general practitioners' attitudes towards this condition. The provision of a range of treatment options, including support groups, is suggested, on the basis of evidence gathered using qualitative methods, as likely to be viewed by women as more appropriate than offering treatment based on the evidence provided by traditional randomized controlled trials.

The population pharmacokinetics of long-term methotrexate in rheumatoid arthritis

AIMS

Methotrexate is considered by many practitioners to be the agent of choice in the treatment of rheumatoid arthritis. The pharmacokinetics of methotrexate have been reported to exhibit significant intersubject variability. Therefore, this study was undertaken to evaluate the population pharmacokinetics of methotrexate during long-term administration in adults with rheumatoid arthritis.

METHODS

Methotrexate pharmacokinetics were evaluated in a 36 month study of 62 adults with rheumatoid arthritis. Patients received oral or intramuscular doses of methotrexate weekly with pharmacokinetic studies performed every 6 months. Data were analyzed with nonlinear mixed effects modeling.

RESULTS

Three thousand two hundred and sixty post oral or intramuscular dose serum methotrexate concentrations comprising 425 individual concentration vs time profiles were modeled using NONMEM. Covariates that significantly (P < 0.005) influenced the disposition of methotrexate were age (AGE, years), body weight (BW, kg), creatinine clearance (CL(CR), 1 h(-1)), gender (GEN; 0 = male, 1 = female), dose (DOSE, micromol), and fed vs fasted state (FED; 0 = fasted, 1 = fed). The final model describing the biexponential disposition of methotrexate was clearance(CL, 1 h(-1)) = (0.0810*BW + 0.257*CL(CR))*(1-(0.167*GEN); central volume (Vc, 1) = 0.311*BW; peripheral volume (Vp, 1) = 0.469*BW-0.169*AGE; intercompartmental clearance (Q, 1 h(-1)) = 4.27*(1-0.355*GEN); oral absorption rate constant (ka(p.o.), h(-1)) = 4.70-0.0439*DOSE*(1-0.507*FED); intramuscular absorption rate constant (ka(i.m.), h(-1)) = 0.122*DOSE; relative bioavailability (F) = 93.4%; and oral absorption lag time (LAG(p.o.), min) = 13.5. Pharmacokinetic parameters (%CV) for a typical fasted male subject in this study were CL, 7.341 h(-1) (27%); Vc, 23.51 (28%); Vp, 25.31 (31%); Q, 4.25 1 h(-1) (41%); ka(p.o.), 3.67 h(-1) (77%); and ka(i.m.), 3.09 h(-1) (44%).

CONCLUSIONS

The population pharmacokinetics of methotrexate in adults with rheumatoid arthritis were well described by this investigation. Substantial interpatient variability was explained by incorporating patient specific data into regression equations predicting pharmacokinetic parameters.

Physical exercise and psychological well being: a critical review

The relation between physical exercise and psychological health has increasingly come under the spotlight over recent years. While the message emanating from physiological research has extolled the general advantages of exercise in terms of physical health, the equivalent psychological literature has revealed a more complex relation. The paper outlines the research evidence, focusing on the relation between physical exercise and depression, anxiety, stress responsivity, mood state, self esteem, premenstrual syndrome, and body image. Consideration is also given to the phenomena of exercise addiction and withdrawal, and implications for exercise prescription are discussed.

[Psychogenic erection and ejaculation disorders in a couple wanting children]

A man aged 40 and his wife aged 29, involuntarily childless due to a psychogenic disturbance of erection and ejaculation, asked for donor insemination. The man had been given psychosexual treatment without success during the preceding 4 years. Before starting donor insemination an ultimate effort to obtain an ejaculate by means of electrovibrator treatment was made, the physician handling the instrument. Two pregnancies were achieved by insemination with semen of the husband. The question is raised whether in a couple with a psychogenic coital disorder who only wish to achieve pregnancy, psychosexual therapy is indicated.

Effect of subchronic 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure on immune system and target gene responses in mice: calculation of benchmark doses for CYP1A1 and CYP1A2 related enzyme activities

The dose-effect relationships were analysed for several noncarcinogenic endpoints, such as immunological and biochemical responses at subchronic, low dose exposure of female C57BL/6 mice to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The animals were treated i.p. with TCDD according to the initial- and maintenance-dose principal for a period of 135 days. The initial doses were 1, 10 and 100 ng TCDD/kg, the weekly maintenance doses were 0.2, 2 and 20 ng TCDD/kg, respectively. At days 23, 79 and 135 of TCDD/kg, treatment 10 animals of each dose group were killed. As immunological parameters the number of thymocytes and the pattern of thymocyte subpopulations were determined. In liver, lung and thymus, mRNA expression of TGF-alpha, TGF-beta(1), TGF-beta(2), TGF-beta(3), TNF-alpha, IL-1 beta and different CYP1 isoforms (CYP1A1, CYP1A2, CYP1B1) was analysed. In the livers, activities of 7-ethoxyresorufin-O-deethylase (EROD) and 7-methoxyresorufin-O-demethylase (MROD) were measured. TCDD content in the liver was determined. The main results are summarized as follows: (1) The TCDD doses were not sufficient to elicit dose-dependent changes of pattern of thymocyte subpopulation. (2) TCDD failed to change the mRNA expression of TGF-alpha, TGF-beta and TNF-alpha, but led to an increase of IL-1 beta mRNA expression in liver, lung and thymus. The results show that the TCDD induced IL-1 beta mRNA increase is at least as sensitive a marker as the induction of CYP1A isoforms. (3) The expression of CYP1B1 mRNA remained unchanged at the doses tested, while CYP1A1 and CYP1A2 mRNA expression was dose-dependently enhanced. EROD and MROD activities in the liver paralleled the increases of CYP1A1 and CYP1A2 mRNA expression. (4) Regression analysis of the data showed that most of the parameters tested fit a linear model. (5) From the data, a benchmark dose for EROD/MROD activities in the livers of female C57BL/6 mice of about 0.03 ng TCDD/kg per day was calculated.

Influence of donor insemination on sexual functions of recipients

This paper presents the results of an investigation by personal interviews by the author, concerning different characteristics of sexual behaviour in 156 women during the period in which donor insemination was performed. The questions concerned sexual desire, orgasm, masturbation, libido alterations during the menstrual cycle, libido of wife compared to libido of husband, influence of sex films and sex books on sexual desire. The conclusion that can be drawn from this study is that donor insemination did not disturb the sexual part of marital life in the interviewed group of women.

Comparative studies on the toxicity of mercury, cadmium, and copper toward the isolated perfused rat liver

The toxic effects of cadmium, mercury, and copper were compared over the over range 0.01, 0.03, and 0.1 mM using the isolated perfused rat liver preparation. All metals caused similar changes in various parameters used to describe general toxicity. Thus reductions in oxygen consumption, perfusion flow, and biliary secretion were found, while lactate dehydrogenase release into the perfusate, as well as liver weight, increased also in a dose-dependent fashion. Each metal caused similar magnitudes of changes and exerted similar potency. Measurement of other parameters indicating more specific injury revealed a number of differences. Although all metals reduced hepatic ATP concentration, mercury and cadmium were more potent than copper in this respect. Cadmium was the most potent at decreasing reduced glutathione levels. Mercury was most effective at increasing tissue calcium content, while copper was less so, and cadmium ineffective. Only copper significantly increased tissue malondialdehyde (MDA) content, while all metals increased its release into perfusate. Furthermore, whereas cadmium seemed the most potent metal in increasing MDA release, it was least efficacious, while copper was the most. Antioxidants such as superoxide dismutase, catalase, and Trolox C only reduced cadmium's influence on MDA in perfusate; however, they did not affect cadmium's ability to alter most other parameters of vitality. Albumin reversed the toxic effects of copper and mercury, but not cadmium. While metal-induced reductions in perfusion flow accounted for some of the toxic effects of the metals investigated, the results as a whole supported the suggestion that all metals exerted toxicity at the mitochondria, since ATP levels were reduced in a manner that could not be reproduced by perfusion flow reduction alone. Lipid peroxidation appears to play little role in determining toxicity induced by any of these metals. Furthermore, albumin may play an important physiological role in preventing hepatic injury that might otherwise be induced through acute metal intoxication.

Murine systemic autoimmune disease induced by mercuric chloride: T helper cells reacting to self proteins

HgCl2 induces a CD4+ T-cell-dependent systemic autoimmune disease in susceptible strains of rats and mice. In rats, autoreactive T cells were shown to be involved, whereas in mice, attention has focussed on the demonstration of 'Hg-specific' T cells. To clarify these seemingly different T cell involvements, T cells from B10.S mice treated with HgCl2 for 1 or 8 weeks were analyzed for their capacity to mount anamnestic responses against various self antigens (Ags) which either contained Hg or did not. T cells from donors short-term treated with HgCl2 failed to mount memory responses to Hg-free Ags, but mounted a significant response to HgCl2 and also reacted with Hg-containing self Ags. Interestingly, T cells from donors long-term treated with HgCl2 showed a different pattern of reactivity. They hardly reacted to HgCl2 and reacted poorly to Hg-containing splenic proteins, but responded vigorously to nuclei and fibrillarin irrespective of whether these self constituents had been treated with HgCl2 or not. Conceivably, the initial activation of T cells that recognize Hg in combination with nuclear self proteins, such as fibrillarin, eventually results in activation of T cells specific for the unaltered self proteins.

Usefulness of follow-up regional cerebral blood flow measurements by single-photon emission computed tomography in the differential diagnosis of dementia

The aim of this study was to evaluate whether follow-up measurements of regional cerebral blood flow (rCBF) by single-photon emission computed tomography (SPECT) provide additional information in the differential diagnosis of dementia. Thirty-six patients (70 +/- 14 yr) with suspected dementia who had two technetium 99m-hexamethylpropyleneamineoxime SPECT scans over 18 +/- 7 months were included in this retrospective study. The patients comprised three groups based on the final clinical diagnosis: (1) neurodegenerative disorder (NDD) including Alzheimer's disease (AD) (n = 13), frontotemporal lobe dementia (n = 2), progressive supranuclear palsy (n = 1), and mixed dementia (AD plus multiinfarct dementia [MID]) (n = 3); (2) MID (n = 8); and (3) psychiatric disorders (depression [n = 7], psychosis [n = 1], and anxiety [n = 1]). Blinded to the clinical diagnosis and using visual analysis, the nuclear medicine physicians compared the second scan with the first scan for each patient to characterize temporal changes in rCBF. SPECT findings were categorized into three patterns of rCBF change: worsened, improved, and unchanged. Of the worsened rCBF group, 17 (85%) belonged to the NDD group whereas 2 (10%) and 1 (5%) belonged to the MID and psychiatric disorders groups, respectively. All 5 (100%) of the improved rCBF patients belonged to the psychiatric disorders group. Thus, worsening of rCBF favors the diagnosis of NDD whereas improvement in rCBF may mitigate against the diagnosis of NDD or MID. Follow-up rCBF measurements by SPECT thus provided additional information on the possible cause of dementia. A prospective study to further evaluate the usefulness of follow-up rCBF measurements by SPECT appears warranted.

Evidence for the promotion of positive selection of thymocytes by Ah receptor agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a ligand for the arylhydrocarbon receptor (Ah receptor), abundant in the murine thymus. In the thymus immunocompetent T cells develop. Upon exposure of murine fetal thymi in organ cultures to TCDD the distribution of mature and immature thymocytes is skewed towards apparently mature, prospective cytotoxic cells of the CD4-CD8+T cell receptor+ phenotype. The normally abundant CD4+ CD8+ cells are decreased. Proliferation of the most immature thymocyte subpopulations is inhibited and maturation of thymocytes appears accelerated by TCDD. Eventually the thymocyte number is significantly decreased. Selective treatment of stroma cells showed them to be the primary target cells of TCDD action. Thymus stroma plays a pivotal role in thymocyte maturation and is indispensable for the selection of thymocytes bearing T cell receptors specific for foreign antigen in the context of self. We tested whether the effects of TCDD on thymocyte differentiation and maturation has further consequences for the selection processes by analysing (a) the repertoire of V beta genes used as a measure for negative selection and (b) the expression of CD69 and bcl-2 by thymocytes as a parameter of positive selection. Our data indicate that TCDD does not cause gross disturbance of negative selection but provide evidence for more cells auditioning for positive selection by TCDD exposure.

Isolation of full-size mRNA from ethanol-fixed cells after cellular immunofluorescence staining and fluorescence-activated cell sorting (FACS)

Preparation of intact, full-size RNA from tissues or cells requires stringent precautions against ubiquitous and rather stable RNases. Fluorescence-activated cell sorting (FACS) usually aims at the isolation of cells according to cell surface markers on living cells, from which RNA can be obtained by standard protocols. The separation of cells according to intracellular immunofluorescence markers, such as intranuclear, intracytoplasmic, or secreted molecules, requires permeation of the cell membrane for the staining antibodies, which is usually achieved by fixation. However, commonly used fixatives such as ethanol, methanol, or formaldehyde do not inactivate RNases completely, thereby hampering the analysis of complete RNA molecules from fixed cells. We report isolation of intact, full-size RNA suitable for Northern blotting from cells that were fixed by 95% ethanol/5% acetic acid containing RNase inhibitors, stained intracellularly, and sorted by FACS.