A prospective case-controlled cohort study of endothelial function in patients with moderate to severe psoriasis

BACKGROUND

There is well-documented evidence that patients with moderate and severe psoriasis have a significantly increased risk of cardiovascular disease (CVD). While this risk can, at least in part, be attributed to the high prevalence of traditional risk factors in the population with psoriasis, some epidemiological evidence suggests it may be independent of these.

OBJECTIVES

This prospective, case-controlled study investigates whether psoriasis is a risk factor for CVD using two, validated, sensitive markers of CVD, endothelial dysfunction and high-sensitivity C-reactive protein (hsCRP).

METHODS

Patients were recruited from a tertiary referral psoriasis clinic and exclusion criteria included established CVD and/or conventional risks for CVD. Preclinical CVD was assessed using flow-mediated brachial artery dilatation, which measures endothelial dysfunction, and hsCRP, a serological marker of atherosclerosis.

RESULTS

Sixty-four patients (22%) out of a total of 285 consecutive patients attending the severe psoriasis clinic were entered into the study. One hundred and sixty-one (56%) were excluded following identification of cardiovascular risk; 39 of the 161 (24%) had at least two cardiovascular risk factors. A further 16 (6%) patients were excluded because of established CVD. No statistically significant difference in endothelial dysfunction was observed between patients with psoriasis (n = 60) and healthy controls (n = 117) (P = 0·508). The hsCRP level was, however, significantly elevated in the psoriasis group (2·828 mg L(-1), SEM 0·219; controls 0·728 mg L(-1), SEM 0·142; P < 0·05).

CONCLUSION

This large, investigative study is the first to assess endothelial function in patients with psoriasis after exclusion of traditional risk factors for CVD. These data suggest that psoriasis per se is not a risk factor for CVD and that elevated hsCRP is possibly independent of atheroma risk. There was a high prevalence of traditional risk factors in our population with severe psoriasis.

Antinuclear antibodies associate with loss of response to antitumour necrosis factor-alpha therapy in psoriasis: a retrospective, observational study

BACKGROUND

An increasing number of patients with severe psoriasis are failing to respond to antitumour necrosis factor (TNF)-alpha therapy (etanercept, infliximab and adalimumab).

OBJECTIVES

We observed that many of these patients developed antinuclear antibodies (ANA) and antidouble-stranded DNA (anti-dsDNA) antibodies while on treatment prompting us to investigate whether their development is associated with anti-TNF treatment failure.

METHODS

All patients with psoriasis who had received anti-TNF therapies were identified and their blood results and treatment histories were obtained from electronic patient records and case notes.

RESULTS

A total of 97 patients had been treated with anti-TNF agents (60 were on their first agent, 22 had been on and stopped one agent, nine had been on and stopped two agents and six had been on and stopped all three agents). ANA developed in 17% of patients on their first treatment, 54% of patients who had failed one treatment, 78% of patients who had failed two treatments and 83% of patients who had failed all three treatments. Anti-dsDNA antibodies developed in 2%, 27%, 33% and 83% of patients from the same respective groups. Significantly, the antibodies developed before treatment had failed with all three agents and their development was not related to the total time that patients had been on anti-TNF therapy.

CONCLUSIONS

This study suggests that the development of ANA and anti-dsDNA antibodies on anti-TNF treatment may act as a marker of forthcoming treatment failure. Large-scale prospective studies are required to assess the importance of this observation.

Treatment of severe, recalcitrant, chronic plaque psoriasis with fumaric acid esters: a prospective study

BACKGROUND

Fumaric acid esters (FAE) are used in Germany as a first-line systemic treatment for chronic plaque psoriasis, with proven efficacy and low toxicity. Their use in the U.K. is variable, and they remain unlicensed. Consequently, efficacy and safety data from U.K. patients is limited and their place in the psoriasis treatment armamentarium is unclear.

OBJECTIVES

To examine the efficacy and safety of FAE in a prospective cohort of U.K. patients with severe, treatment-recalcitrant, chronic plaque psoriasis.

METHODS

A single-centre, open, nonrandomized, prospective study was performed in a regional referral centre for patients with severe psoriasis. Outcomes were measured by the Psoriasis Area and Severity Index (PASI), Dermatology Life Quality Index (DLQI), blood investigations and adverse events monitoring.

RESULTS

Eighty patients were recruited. Fifty-nine per cent were taking a concomitant oral antipsoriatic agent; 20% achieved a PASI-50, 8% a PASI-75 and 4% a PASI-90 on intention-to-treat analysis at 3 months with an overall, statistically significant, reduction in PASI from 13.9 + or - 9.0 to 11.3 + or - 9.2 (P < 0.0001). At 3 months, lymphopenia was seen in 33% of the cohort with significantly lower counts in patients responsive to FAE (P = 0.008). In addition, by 3 months, 36% of concomitant antipsoriatic medication had been stopped and 25% of doses had been reduced without loss of disease control. Side-effects (most commonly diarrhoea, abdominal pain and flushing) were reported by 74% of patients resulting in cessation of FAE in 36%.

CONCLUSIONS

FAE is a useful alternative treatment option in patients with severe, treatment-resistant, chronic plaque psoriasis and can allow dose reduction, and subsequent cessation, of other, potentially more toxic agents.

Treatment of severe, recalcitrant, chronic plaque psoriasis with fumaric acid esters: a prospective study

BACKGROUND

Fumaric acid esters (FAE) are used in Germany as a first-line systemic treatment for chronic plaque psoriasis, with proven efficacy and low toxicity. Their use in the U.K. is variable, and they remain unlicensed. Consequently, efficacy and safety data from U.K. patients is limited and their place in the psoriasis treatment armamentarium is unclear.

OBJECTIVES

To examine the efficacy and safety of FAE in a prospective cohort of U.K. patients with severe, treatment-recalcitrant, chronic plaque psoriasis.

METHODS

A single-centre, open, nonrandomized, prospective study was performed in a regional referral centre for patients with severe psoriasis. Outcomes were measured by the Psoriasis Area and Severity Index (PASI), Dermatology Life Quality Index (DLQI), blood investigations and adverse events monitoring.

RESULTS

Eighty patients were recruited. Fifty-nine per cent were taking a concomitant oral antipsoriatic agent; 20% achieved a PASI-50, 8% a PASI-75 and 4% a PASI-90 on intention-to-treat analysis at 3 months with an overall, statistically significant, reduction in PASI from 13.9 + or - 9.0 to 11.3 + or - 9.2 (P < 0.0001). At 3 months, lymphopenia was seen in 33% of the cohort with significantly lower counts in patients responsive to FAE (P = 0.008). In addition, by 3 months, 36% of concomitant antipsoriatic medication had been stopped and 25% of doses had been reduced without loss of disease control. Side-effects (most commonly diarrhoea, abdominal pain and flushing) were reported by 74% of patients resulting in cessation of FAE in 36%.

CONCLUSIONS

FAE is a useful alternative treatment option in patients with severe, treatment-resistant, chronic plaque psoriasis and can allow dose reduction, and subsequent cessation, of other, potentially more toxic agents.

Outcomes of methotrexate therapy for psoriasis and relationship to genetic polymorphisms

Background

The use of methotrexate is limited by interindividual variability in response. Previous studies in patients with either rheumatoid arthritis or psoriasis suggest that genetic variation across the methotrexate metabolic pathway might enable prediction of both efficacy and toxicity of the drug.

Objectives

To assess if single nucleotide polymorphisms (SNPs) across four genes that are relevant to methotrexate metabolism [folypolyglutamate synthase (FPGS), gamma-glutamyl hydrolase (GGH), methylenetetrahydrofolate reductase (MTHFR) and 5-aminoimidazole-4-carboxamide ribonucleotide transformylase (ATIC)] are related to treatment outcomes in patients with psoriasis.

Methods

DNA was collected from 374 patients with psoriasis who had been treated with methotrexate. Data were available on individual outcomes to therapy, namely efficacy and toxicity. Haplotype-tagging SNPs (r² > 0·8) for the four genes with a minor allele frequency of > 5% were selected from the HAPMAP phase II data. Genotyping was undertaken using the MassARRAY spectrometric method (Sequenom®).

Results

There were no significant associations detected between clinical outcomes in patients with psoriasis treated with methotrexate and SNPs in the four genes investigated.

Conclusions

Genetic variation in four key genes relevant to the intracellular metabolism of methotrexate does not appear to predict response to methotrexate therapy in patients with psoriasis.

DRESS syndrome caused by efalizumab

We report a case of drug reaction with eosinophilia and systemic symptoms (DRESS) to efalizumab. A 52-year-old man developed a widespread papulovesicular rash after 4 weeks of treatment with efalizumab (1.0 mg/kg/week) for treatment-resistant severe psoriasis. Histology revealed a subepidermal blister with eosinophil-rich inflammatory cell infiltrate. Subsequently, the patient developed high peripheral eosinophilia, abnormal liver function, malaise and fever, all requiring inpatient admission. Efalizumab was discontinued immediately, but the rash persisted for 4 months and was only controlled by oral prednisolone at a dose of 30 mg/day. To our knowledge, this is the first reported case of DRESS caused by efalizumab.

Polymorphisms in Folate, Pyrimidine, and Purine Metabolism Are Associated with Efficacy and Toxicity of Methotrexate in Psoriasis

Methotrexate is the gold standard therapy for moderate to severe psoriasis, but there is marked interpersonal variation in its efficacy and toxicity. We hypothesized that in psoriasis patients, specific common polymorphisms in folate, pyrimidine, and purine metabolic enzymes are associated with methotrexate efficacy and/or toxicity. DNA from 203 retrospectively recruited psoriasis patients treated with methotrexate was collected and genotyped by restriction endonuclease digestion or length polymorphism assays. The reduced folate carrier (RFC) 80A allele and the thymidylate synthase (TS) 3'-untranslated region (3'-UTR) 6 bp deletion were associated with methotrexate-induced toxicity (P=0.025 and P=0.025, respectively). RFC 80A and 5-aminoimidazole-4-carboxamide ribonucleotide transformylase (ATIC) 347G were associated with methotrexate discontinuation (P=0.048 and P=0.038). The TS 5'-UTR 28 bp 3R polymorphism correlated with poor clinical outcome (P=0.029), however, this was not the case when patients with palmoplantar pustular psoriasis were not included in the analysis. Stronger associations between specific polymorphisms and methotrexate-induced toxicity and discontinuation were found in a subanalysis of patients on methotrexate not receiving folic acid supplementation. We have demonstrated preliminary evidence that specific polymorphisms of enzymes involved in folate, pyrimidine, and purine metabolism could be useful in predicting clinical response to methotrexate in patients with psoriasis.

Long-term Safety and Efficacy of Tacrolimus Ointment for the Treatment of Atopic Dermatitis in Children

Tacrolimus ointment is a topical calcineurin inhibitor for the treatment of atopic dermatitis. The primary objective of this open-label study was to assess the long-term safety of tacrolimus ointment. The primary end-point was the incidence of adverse events. Secondary end-points included the Eczema Area and Severity Index and a modified version of this index. A total of 466 children with atopic dermatitis, aged 2-15 years, applied 0.03% or 0.1% tacrolimus ointment twice daily for up to 29.5 months. Skin burning and pruritus were the most common application site events; their prevalence decreased over time. There was no increase in viral infections or other adverse events over time. Laboratory profiles were consistent with those reported in atopic populations. Substantial improvement in all efficacy end-points was observed by week 2 and maintained throughout the study. Long-term treatment with tacrolimus ointment is safe and effective in these patients with atopic dermatitis.

IGF regulation of neutral amino acid transport in the BeWo choriocarcinoma cell line (b30 clone): evidence for MAP kinase-dependent and MAP kinase-independent mechanisms

OBJECTIVE

IGF-1 and IGF-1 receptors are major determinants of fetal growth and are expressed primarily on the maternal-facing surface of the syncytiotrophoblast cell membrane in the human placenta. IGF-1 regulates fetal growth, in part, by regulating amino acid transport across the placenta. The objective of these studies was to study the role of IGF-1 and its signaling pathway in regulating neutral amino acid transport in a human trophoblast cell culture model.

DESIGN

The regulation of neutral amino acid transport by IGF-1 was studied in cultured BeWo(b30) choriocarcinoma cells using the non-metabolizing amino acid analog, [(3)H]-alpha-aminoisobutyric acid (AIB). Transport in the absence of Na was used to distinguish system L from total AIB transport. Similarly, Na-dependent transport in the presence of excess methyl-AIB (MeAIB) permitted discrimination of systems A (MeAIB-sensitive) and ASC (MeAIB-insensitive). Specific inhibitors of intracellular signaling pathways were then used to determine the signaling pathway utilized by IGFs to regulate each amino acid transport system. Specificity of inhibition was assessed using specific markers of p70 S6 kinase activity and MAP kinase activation.

RESULTS

Maximal stimulating concentrations of IGF-I (100 ng/ml) stimulated AIB transport by 30-40% exclusively through system A. Wortmannin (100 nM), an inhibitor of PI-3-kinase activity, inhibited all IGF-I-stimulated transport. Rapamycin (100 ng/ml), an inhibitor of p70 S6 kinase, and bisindolylmaleimide, an inhibitor of protein kinase C (PKC), had no effect. PD-098059 (50 miccroM), an inhibitor of MAP kinase activation, inhibited 20-30% of basal AIB transport but did not inhibit IGF-I-stimulated transport under the conditions studied. IGF-1 did not increase steady state mRNA levels of the system A transporters, SNAT1 and SNAT2, suggesting IGF-1 stimulates transport via post-transcriptional mechanisms.

CONCLUSIONS

These data demonstrate that IGF-I stimulates neutral amino acid transport system A by a PI3-kinase dependent, post-transcriptional pathway in the BeWo(b30) cell line. Additionally, system A activity appear to be sensitive to MAP kinase-dependent pathways not regulated by IGFs.

Killed Mycobacterium vaccae suspension in children with moderate-to-severe atopic dermatitis: a randomized, double-blind, placebo-controlled trial

BACKGROUND

The hygiene hypothesis is often proposed to explain the high prevalence of atopy in the western world. Dysregulation of the immune system may result from inadequate exposure to micro-organisms such as mycobacteria. A small trial suggested that a killed extract of Mycobacterium vaccae ameliorates atopic dermatitis (AD).

OBJECTIVES

To confirm in a large clinical trial whether killed M. vaccae ameliorates AD in 5-16-year-old children.

METHODS

This was a randomized, placebo-controlled, double-blind, multi-centre study of the effect of intradermal injection of killed M. vaccae (0.1 or 1 mg) on patients, aged 5-16, with moderate-to-severe AD. Patients were followed up for 24 weeks. The primary end point was the change in severity of AD at 12 weeks, assessed using the six area, six-sign, atopic dermatitis (SASSAD) score. Secondary end points included changes in disease extent, patient's global assessment and children's dermatology life quality index.

RESULTS

There were 166 patients randomized. The mean SASSAD score fell to a similar degree at week 12 in all treatment arms: from 33 to 24, (26%) in the high-dose group, from 30 to 23 (25%) in the low-dose group and from 36 to 27 (24%) in the placebo group (P>0.05). Secondary end points followed the same trend. Adverse events were generally those expected to occur in this population. Injection site reactions occurred in 32 patients at week 4.

CONCLUSIONS

M. vaccae was no more effective than the placebo in ameliorating the severity of AD.

Infliximab for severe, treatment-resistant psoriasis: a prospective, open-label study

BACKGROUND

Infliximab, a mouse-human chimeric monoclonal antibody directed against tumour necrosis factor-alpha, has been shown to be effective for moderate to severe psoriasis, but there are few data published on its use in recalcitrant, treatment-resistant disease or in combination with other antipsoriatic therapies.

OBJECTIVES

To report our experience with infliximab in the treatment of patients attending a tertiary referral service with severe recalcitrant disease.

METHODS

All patients attending a tertiary referral service for severe psoriasis who were treated with infliximab between 2002 and July 2005 were entered into a prospective, open-label study. Details on disease phenotype, clinical course and adverse events were recorded together with measures of disease severity [Psoriasis Area and Severity Index (PASI), Dermatology Life Quality Index, clinical photography] at baseline, weeks 2 and 6, and then at 2-monthly intervals throughout the treatment period.

RESULTS

Twenty-three patients were treated with infliximab during the study; one patient had pustular psoriasis and was therefore excluded from statistical analysis. All had severe disease (baseline PASI 26.5+/-6.7, mean+/-SD, n=22) and had received at least two systemic therapies for psoriasis in the past; 16 were taking one or more concomitant therapies at the time of treatment initiation. At week 10, 95% had achieved a 50% or greater improvement in baseline PASI (PASI 50), and 77% had achieved a 75% or greater improvement (PASI 75). Efficacy was sustained in the longer term, with eight of 10 patients on treatment for more than 11 months maintaining at least a PASI 50. Only one patient had treatment withdrawn due to lack of efficacy, two suffered severe systemic infections including extrapulmonary tuberculosis (splenic abscess) and cellulitis, and six have discontinued due to adverse effects including infusion reactions (two), severe thrombocytopenia (one), hepatitis (one) and malignancy (two).

CONCLUSIONS

Data from this open-label study suggest that infliximab is a rapidly effective treatment for patients with severe, treatment-resistant disease, although approximately 25% of patients had to discontinue therapy due to the development of serious adverse effects. Long-term follow-up, continued pharmacovigilance, and further controlled comparative studies will be required to evaluate fully the risks associated with infliximab in the context of this already difficult to treat population.

Interaction between Genetic Control of Vascular Endothelial Growth Factor Production and Retinoid Responsiveness in Psoriasis

Vascular endothelial growth factor (VEGF) promotes angiogenesis, and elevated levels are found in plaques of psoriasis. Two VEGF polymorphisms, +405 and -460, are associated with early-onset psoriasis and are close to the functional activator protein-1 site (+419) through which retinoids, an established systemic therapy for psoriasis, can block production of VEGF. We report that peripheral blood mononuclear cells (PBMCs) and epidermal keratinocytes (KC) from patients with psoriasis demonstrate differential, genotype-dependent, regulation of VEGF. For PBMCs, VEGF genotype distinguishes two groups of patients with psoriasis - "high and low VEGF producers" (P < 0.001). In contrast, KC production of VEGF is not genotype dependent. However, the effects of all-trans retinoic acid (RA) on cellular expression of VEGF are determined by both cell type and genotype. RA inhibits KC production of VEGF in a genotype-dependent manner (P < 0.005) whereas RA stimulates PBMCs production irrespective of VEGF genotype (P < 0.001). We also report that the -460 VEGF polymorphism appears to have a clinical pharmacogenetic role in predicting response or non-response of psoriasis to acitretin (P = 0.01). In future, determination of VEGF gene polymorphisms and thus individual patient VEGF "signatures" may be used as a prognostic factor for psoriasis susceptibility/severity and as a means for optimizing treatment response.

Apolipoprotein E gene polymorphisms are associated with psoriasis but do not determine disease response to acitretin

BACKGROUND

Psoriasis is associated with abnormal plasma lipid metabolism and a high frequency of cardiovascular events. Increased lipid levels are also seen in patients with psoriasis treated with acitretin. Apolipoprotein E (ApoE) variants have been linked to hypertriglyceridaemia and hypercholesterolaemia in normal individuals. Two coding single nucleotide polymorphisms at +3937 and +4075 define the three common ApoE alleles e2, e3 and e4.

OBJECTIVES

To test the hypothesis that particular ApoE polymorphism(s) are associated with psoriasis and that specific ApoE allelic variant(s) may be a marker for predicting disease response to acitretin.

METHODS

DNA was genotyped for ApoE polymorphisms using a radioactive hybridization technique in cohorts of patients with psoriasis, including patients with chronic plaque psoriasis (CPP, n = 212), guttate psoriasis (GP, n = 94), palmoplantar pustulosis (PPP, n = 101), controls (n = 137), acitretin responders (n =106) and acitretin nonresponders (n = 84).

RESULTS

The frequency of the e4 allele (+3937C/+4075C) was significantly higher in patients with CPP and GP than in controls (P = 0.008 and P = 0.02, respectively). There was no significant difference in allele frequencies between patients with PPP and controls. Allelic distribution was similar in acitretin responders and nonresponders.

CONCLUSIONS

These data demonstrate an association between the Apo e4 allele and CPP and GP, suggesting a possible pathogenic role for ApoE in psoriasis. Our results do not support a link between disease response to acitretin and the e2, e3 or e4 allelic variants of ApoE.

Replacement of routine liver biopsy by procollagen III aminopeptide for monitoring patients with psoriasis receiving long-term methotrexate: a multicentre audit and health economic analysis

BACKGROUND

Patients receiving long-term methotrexate for psoriasis are at risk of developing hepatic fibrosis. Repeated liver biopsy has long been regarded as the only reliable method of detecting this and it is still recommended by the American Academy of Dermatology (AAD). More recently, monitoring by serum procollagen III aminopeptide (PIIINP) measurement (Orion Diagnostica, Espoo, Finland) has been advocated as a means of significantly reducing the need for liver biopsy.

OBJECTIVES

To assess the validity of guidelines developed in Manchester for the use of PIIINP to monitor patients with psoriasis receiving long-term methotrexate; to assess the anticipated benefits to patients of introducing this change in practice, including reduction in requirement for liver biopsy; and to determine the impact of its introduction on healthcare costs.

METHODS

A multicentre audit was conducted over a 24-month period to compare the healthcare costs and outcomes of two intervention groups from centres where serial PIIINP measurement was employed with those of two control groups from centres in which AAD guidelines were followed.

RESULTS

A sevenfold reduction in the need for liver biopsy was observed in the two intervention groups (n = 166; 0.04 and 0.02 biopsies/patient/year, respectively) compared with the two control groups (n = 87; 0.26 and 0.30 biopsies/patient/year, respectively). Abnormalities of sufficient severity to influence management were identified in one in five patients biopsied in the main intervention group compared with one in 16 in the control groups. The overwhelming majority of patients surveyed expressed a preference for being monitored by methods that would minimize the need for liver biopsy. The adoption of PIIINP for monitoring would result in significant cost savings.

CONCLUSIONS

This audit has shown that patients managed by the Manchester protocol using serial PIIINP measurement and selective liver biopsy were not disadvantaged in comparison with those managed according to AAD guidelines; they were subjected to sevenfold fewer liver biopsies without evidence that important liver toxicity was missed in the process. If PIIINP monitoring were widely adopted, methotrexate would become a more acceptable option for many patients who are dissuaded from considering it because of the threat of repeated liver biopsy; it would also result in significant savings to the healthcare budget.

Does topical tacrolimus induce lentigines in children with atopic dermatitis? A report of three cases

Three children with severe atopic dermatitis were noted at routine follow-up to have developed multiple small pigmented macules during long-term therapy with topical tacrolimus 0.1% (Protopic, Fujisawa). Representative lesions in two of the three cases were confirmed histologically as simple lentigines. The focal distribution of lentigines to sites of tacrolimus use, and the temporal association between use of tacrolimus and development of lesions, suggest that topical tacrolimus is of direct aetiological relevance to their development. Careful long-term follow-up will be required to assess the clinical implications of these findings and whether they represent an increase in risk for melanocytic neoplasia.

Successful treatment of severe psoriasis and psoriatic arthritis with adalimumab

Adalimumab, a fully human-derived recombinant monoclonal antibody against tumour necrosis factor-alpha, has been shown to be effective for the treatment of patients with moderately to severely active rheumatoid arthritis. We report two patients with long-standing recalcitrant psoriasis and psoriatic arthritis who, after multiple treatment failures with conventional and experimental antipsoriatic medications, both responded to treatment with adalimumab. Significant clinical improvement was noted in both skin and joint disease in the two patients after several weeks of treatment with adalimumab. We are unaware of previous published reports of adalimumab therapy in patients with psoriasis and psoriatic arthritis.

Further additions to the bibliography of Alfred Russel Wallace (1823-1913)

Twenty-one previously unrecorded published writings by the English naturalist Alfred Russel Wallace (1823-1913) are noticed. The writings vary greatly in date, size and importance, and include items pertaining both to Wallace's natural history as well as social and political interests

Isoforms of amino acid transporters in placental syncytiotrophoblast: plasma membrane localization and potential role in maternal/fetal transport

Many cell proteins exist as isoforms arising either from gene duplication or alternate RNA splicing. There is growing evidence that isoforms with different, but closely related, functional characteristics are often directed to discrete cellular locations. Thus, specialized functions may be carried out by proteins of similar evolutionary origin in different membrane compartments. In polarized epithelial cells, this mechanism allows the cell to control amino acid transport independently at each of its specialized apical and basolateral plasma membrane domains. Investigations of isoform localization in these membranes have generally been performed in epithelia other than the placental trophoblast.This review of placental amino acid transporter isoforms first provides an overview of their properties and preliminary plasma membrane localization. We then discuss studies suggesting various roles of isoform localization in trophoblast function. To provide insights into the molecular basis of this localization in trophoblast, we present a review of current knowledge of plasma membrane protein localization as derived from investigations with a widely used epithelial model cell line. Finally, we discuss a potential approach using cultured trophoblast-derived cells for studies of transporter isoform localization and function. We hope that this review will stimulate investigation of the properties of trophoblast transporter isoforms, their membrane localization and their contribution to the cellular mechanism of maternal-fetal nutrient transport.

Hypoxia reduces expression and function of system A amino acid transporters in cultured term human trophoblasts

We tested the hypothesis that hypoxia diminishes the expression and transport of neutral amino acids by system A in full-term human trophoblasts. Cytotrophoblasts from normal human placentas were cultured in standard conditions of 20% O(2) or in 1% and 3% O(2) for 24 h before assay. Neutral amino acid transport for systems A, ASC, and L was assayed at 24 and 72 h by the cluster-tray technique. Hypoxia during the initial 24 h of culture reduced system A transport by 82% in 1% O(2) and by 37% in 3% O(2) (P < 0.01) compared with standard conditions. Hypoxia during the latter 24 h of the 72 h in culture reduced system A transport by 55% in 1% O(2) and by 20% in 3% O(2) (P < 0.05) compared with standard conditions at 72 h. Hypoxia (1% O(2)) also reduced total amino acid transport by 40% in the more differentiated syncytiotrophoblasts present at 72 h. Northern analysis of trophoblasts in standard conditions showed that subtypes of human amino acid transporter A (hATA1 and hATA2) were each expressed in cytotrophoblasts and syncytiotrophoblasts. Hypoxia decreased expression of hATA1 and hATA2 in both trophoblast phenotypes. We conclude that hypoxia downregulates system A transporter expression and activity in cultured human trophoblasts.

Lysine uptake by cloned hCAT-2B: comparison with hCAT-1 and with trophoblast surface membranes

To study the cationic amino-acid transporter hCAT-2B of human placenta, total RNA was harvested from primary cultured trophoblast and from the BeWo choriocarcinoma cell line (b30 clone) and used for reverse transcription (RT) and polymerase chain reaction (PCR). Primers based on published sequences identified expression of mRNA for hCAT-2B. RT-PCR yielded a 2.06 kb hCAT-2B cDNA, which was cloned. hCAT-2B cRNA injection into Xenopus laevis oocytes stimulated saturable lysine uptake (Km approximately 125 mM). In the presence of Na+, uptake was completely inhibited by L-arginine but only partially by neutral amino acids. To compare directly the interaction of hCAT-1 and hCAT-2B with neutral amino acids and sodium, we examined the inhibition of these transporters by L-leucine and L-alanine over a wide concentration range. L-Alanine and L-leucine inhibit uptake by hCAT-2B substantially less completely than uptake by hCAT-1. The interaction of hCAT-2B resembles that of system y+ in the microvillous membrane of human placenta, while that of hCAT-1 is more comparable to that of system y+ in basal membrane. The identification and characterization of the various cationic amino-acid transporters of the human placenta have the potential to increase the understanding of the cellular mechanism of transplacental transfer.

Stable polarized expression of hCAT-1 in an epithelial cell line

Our laboratory has recently identified and cloned three cationic amino-acid transporters of human placenta. We have now examined the plasma membrane domain localization and functional expression of one of these transporters, hCAT-1, in a polarized epithelial cell line (MDCK). To facilitate identification of expressed protein we first transferred the hCAT-1 cDNA to a vector with C-terminal green fluorescent protein (GFP). The resultant hCAT-1-CT-GFP fusion protein stimulated L-[3H] lysine uptake in Xenopus oocytes. In confluent monolayers of stably transfected cells grown on porous nitrocellulose filters, saturable uptake of L-[3H] lysine from the basolateral surface was stimulated 7-fold over that of untransfected cells. Concentration-dependence studies in Na+-free medium at pH 7.4 demonstrated a Km of approximately 68 +/- 13 microM and a Vmax of 970 +/-170 pmol/mg protein/min. Uptake from the apical plasma membrane surface was negligible in both transfected and untransfected cells. Consistent with these results, confocal microscopy of confluent monolayers of hCAT-1-CT-GFP-expressing cells revealed localization of the transporter solely on the basolateral domain of the cell. This is apparently the first report of a cultured polarized epithelial cell model for stable expression of a cationic amino-acid transporter. It has the potential to aid in the identification of targeting signals for transport protein localization.

Pharmacogenetics in clinical dermatology

Systemic therapies are increasingly used in the management of common skin diseases, and drug toxicity and relative lack of efficacy remain significant problems. In addition, we are unable to predict life-threatening adverse reactions such as toxic epidermal necrolysis. Pharmacogenetics, the study of how genetic differences influence the variability of individual patient responses to drugs, aims to distinguish responders from non-responders and predict those in whom toxicity is likely. Successful application of pharmacogenetics should lead to rationalized drug therapy. Recent advances in molecular genetic techniques such as high-throughput genotyping and microarrays have the potential to provide a practicable and economical approach to future pharmacogenetic testing. Pharmacogenetics will change not only the way drugs are selected but will also impact on clinical trial design and the costs of healthcare delivery.

Swallowing and voice effects of Lee Silverman Voice Treatment (LSVT): a pilot study

OBJECTIVE

To define the effects of Lee Silverman Voice Treatment (LSVT on swallowing and voice in eight patients with idiopathic Parkinson's disease.

METHODS

Each patient received a modified barium swallow (MBS) in addition to voice recording before and after 1 month of LSVT. Swallowing motility disorders were defined and temporal measures of the swallow were completed from the MBS. Voice evaluation included measures of vocal intensity, fundamental frequency, and the patient's perception of speech change.

RESULTS

before LSVT, the most prevalent swallowing motility disorders were oral phase problems including reduced tongue control and strength. Reduced tongue base retraction resulting in residue in the vallecula was the most common disorder in the pharyngeal stage of the swallow. Oral transit time (OTT) and pharyngeal transit time (PTT) were prolonged. After LSVT, there was an overall 51% reduction in the number of swallowing motility disorders. Some temporal measures of swallowing were also significantly reduced as was the approximate amount of oral residue after 3 ml and 5 ml liquid swallows. Voice changes after LSVT included a significant increase in vocal intensity during sustained vowel phonation as well as during reading.

CONCLUSIONS

LSVT seemingly improved neuromuscular control of the entire upper aerodigestive tract, improving oral tongue and tongue base function during the oral and pharyngeal phases of swallowing as well as improving vocal intensity.

Effects of xerostomia on perception and performance of swallow function

BACKGROUND

Head and neck cancer treatment with high-dose chemoradiation may cause xerostomia and affect the patient's perception of swallowing ability.

METHOD

Whole saliva production was measured in 36 patients with advanced-stage cancer of the oropharynx before treatment and 3 months after treatment by weighing a 4 x 4 inch gauze before and after a 2-minute chewing period. Presence of multiple eating difficulties was measured by patient interview. Swallowing was examined videofluorographically (VFG).

RESULTS

Saliva weight decreased from a mean (SEM) of 5.1 (0.5) g pretreatment to 1.4 (0.5) g after treatment (p<.0001). At 3 months, significantly more patients perceived difficulty swallowing, dry mouth, needing water while eating, food stuck in the mouth or throat, and change in taste. Saliva weight was not correlated with VFG measures of bolus transit or observations of residue.

CONCLUSIONS

Chemoradiation treatment results in xerostomia and a significant increase in patient perception of swallowing difficulties. Saliva weight in patients who perceive swallowing problems was lower. Xerostomia did not affect the physiologic aspects of bolus transport. Xerostomia affected the sensory process and comfort of eating more than bolus transport.

Differential susceptibility of heart, skin, and islet allografts to T cell-mediated rejection

Although it is widely accepted that there is a hierarchy in the susceptibility of different allografts to rejection, the mechanisms responsible are unknown. We show that the increased susceptibility of H-2K(b+) skin and islet allografts to rejection is not based on their ability to activate more H-2K(b)-specific T cells in vivo; heart allografts stimulate the activation and proliferation of many more H-2K(b)-specific T cells than either skin or islet allografts. Rejection of all three types of graft generate memory cells by 25 days posttransplant. These data provide evidence that neither tissue-specific Ags nor, surprisingly, the number of APCs carried in the graft dictate their susceptibility to T cell-mediated rejection and suggest that the graft microenvironment and size may play a more important role in determining the susceptibility of an allograft to rejection and resistance to tolerance induction.

A randomized comparison of 4 weeks of terbinafine vs. 8 weeks of griseofulvin for the treatment of tinea capitis

BACKGROUND

Tinea capitis is a common childhood infection that has recently become more frequent in urban areas in Europe and the U.S.A. The current licensed treatment in children is griseofulvin 10 mg kg(-1) daily, which is usually given for 6--8 weeks.

OBJECTIVES

To compare this treatment with a 4-week course of oral terbinafine.

METHODS

Terbinafine was given at the following doses: in children weighing < 20 kg, 62.5 mg daily; 20--40 kg, 125 mg daily; > 40 kg, 250 mg daily. Two hundred and ten children aged 2--16 years, with mycologically confirmed tinea capitis, were randomized to 4 weeks treatment with terbinafine or 8 weeks with griseofulvin, and followed for a total of 24 weeks to determine the difference between treatments with respect to short- and long-term efficacy and tolerability.

RESULTS

One hundred and forty-seven patients were evaluable (terbinafine 77, griseofulvin 70). Although the 4-week course of terbinafine resulted in a trend to more rapid clearance of tinea capitis, there were no statistically significant differences between the two drugs in terms of overall outcome or tolerability, apart from in a subgroup of patients with Trichophyton infections, and weighing > 20 kg, who responded better to terbinafine than to griseofulvin at 4 weeks. By contrast, there was a better response to griseofulvin than to terbinafine in patients with Microsporum audouinii infections.

CONCLUSIONS

Overall, the study showed that 4 weeks of treatment with oral terbinafine has similar efficacy to 8 weeks of treatment with griseofulvin for the management of tinea capitis in children.

A double blind, randomized, controlled clinical trial to assess the efficacy of a new coal tar preparation (Exorex) in the treatment of chronic, plaque type psoriasis

Exorex is a new topical formulation for the treatment of psoriasis; it contains 1% coal tar and a synthetic analogue resembling components identified in banana skin (a complex of esterified essential fatty acids). To determine whether the esterified essential fatty acid complex confers any therapeutic advantage over coal tar alone, patients with chronic plaque psoriasis (n = 20) were entered into a double-blind, randomized, right/left comparison of Exorex, and Exorex without the essential fatty acid component (known hereafter as coal tar control) for 8 weeks. Target plaques were scored (0-4) for erythema, desquamation and infiltration at day 0 and at 2 week intervals throughout the study. No significant differences were detected between Exorex and coal tar control with respect to changes in the summed scores at baseline and following 8 weeks of treatment (mean difference in summed score changes from baseline between Exorex and coal tar control 0.2, 95% confidence interval - 0.44 to 0.84; P = 0.52) or in the area under the response-time curve (P = 0.16). Mean percentage improvement in summed scores of target plaques were 53.9% (SE = 4%) and 56.1% (SE = 4.9%) for Exorex and coal tar control, respectively. Results suggest that the complex of esterified essential fatty acids is not exerting any clinically important therapeutic effect in the treatment of chronic plaque psoriasis.

New approaches to topical therapy

Despite the rapid and proven efficacy of topical corticosteroids, side-effects can limit their clinical usefulness. Topically active macrolide immunosuppressants such as ascomycin and tacrolimus appear to provide comparable therapeutic potency without significant local or adverse effects. Data from ongoing studies will be crucial in determining the safety of these agents in the long term, and also their place within the current therapeutic armamentarium available for patients with atopic dermatitis. Enzyme inhibitors of PLA(2) and PDE 4 currently in the very early stages of clinical development also show potential promise as additional alternative strategies to topical treatment and may perhaps act as steroid sparing agents. Having been in the therapeutic doldrums for years, topical management of atopic dermatitis is likely to show great changes in the very near future.

Temporal and biomechanical characteristics of oropharyngeal swallow in younger and older men

As the U.S. population ages, there is increasing need for data on the effects of aging in healthy elderly individuals over age 80. This investigation compared the swallowing ability of 8 healthy younger men between the ages of 21 and 29 and 8 healthy older men between the ages of 80 and 94 during two swallows each of 1 ml and 10 ml liquid. Videofluoroscopic studies of these swallows were analyzed to confirm the absence of swallowing disorders. Biomechanical analysis of each swallow was completed, from which data on temporal, range of motion, and coordination characteristics of the oropharyngeal swallow were taken. Position of the larynx at rest, length of neck, and pattern of hyoid bone movement were also compared between the two groups. None of the younger or older men exhibited any swallowing disorders. The C2 to C4 distance of older men was significantly shorter than that of younger men, and laryngeal position at rest was lower than in younger men but not significantly so. Older men had a significantly longer pharyngeal delay than younger men and significantly faster onset of posterior pharyngeal wall movement in relation to first cricopharyngeal opening. The older men exhibited significantly reduced maximum vertical and anterior hyoid movement as compared to the younger men even when accounting for the difference in C2 to C4 distance in older men. These data support the hypothesis of reduced muscular reserve in the swallows of older men as compared to younger men. Older men also exhibited less width of cricopharyngeal opening than younger men at 10 ml volume, indicating less upper esophageal sphincter flexibility in the swallows of older men. The potential for exercise to improve reserve is discussed. Significant changes in extent of hyoid elevation and duration of cricopharyngeal opening were seen as liquid bolus volume increased.

Guidelines for the management of tinea capitis. British Association of Dermatologists

These guidelines for the management of tinea capitis have been prepared for dermatologists on behalf of the British Association of Dermatologists. They present evidence-based guidance for treatment, with identification of the strength of evidence available at the time of preparation of the guidelines, and a brief overview of epidemiological aspects, diagnosis and investigation.

Transactivation of a target gene through feedforward loop activation in plants

The expression of many genes encoding transcriptional activators in prokaryotes and eukaryotes is upregulated through positive feedback activation. During positive feedback activation, a transcriptional activator binds to its own promoter and thus increases its own expression as well as the expression of its target genes. In the simplest case, increased levels of the transcriptional activator can be directly correlated with increased expression of its target genes. In this study, we present a gene expression system, designated feedforward loop (FFL) system, which makes use of this kind of positive feedback regulation for the expression of plant transgenes. We show in transient and stable transformation experiments that such a system is functional and that it can be used to obtain high level gene expression in plants. We also provide evidence that the transgene is ubiquitously expressed when using the FFL system. Finally, we discuss the possibilities of using FFL gene expression systems for applications in plant molecular genetics and biotechnology.

Laparoscopic repair of a ruptured diaphragm secondary to blunt trauma

The diagnosis of acute diaphragmatic rupture can be a challenge for even the most experienced clinician. The treatment of the rupture and its concomitant injuries, particularly in the elderly, can be associated with significant morbidity and mortality. The advent of laparoscopy for both the diagnosis and repair of this condition has allowed a more minimally invasive approach. We present the case of a 70-year-old woman who was hurt in a motor vehicle crash. On admission, her physical exam showed left upper quadrant tenderness and bruising. The chest radiograph was suggestive of a ruptured diaphragm. She was taken to the operating room and explored laparoscopically. After a thorough exploration of all the abdominal contents, a tear in the diaphragmatic hiatus to the right of the esophagus was noted. The stomach and small intestine were returned to the abdomen, and the diaphragmatic rupture was repaired. We conclude that laparoscopic exploration and repair of a ruptured diaphragm in a bluntly injured patient is a safe and effective option in selected cases.

Polarized distribution of interleukin-1 receptors and their role in regulation of serotonin transporter in placenta

We investigated the expression of interleukin-1 (IL-1) receptors and their involvement in the regulation of the serotonin transporter gene expression in human placenta. IL-1beta is an activator of the serotonin transporter gene expression in JAR human placental choriocarcinoma cells as demonstrated by an increase in the steady-state levels of the transporter mRNA and in serotonin transport activity. This activation is blocked by IL-1 receptor antagonist. Genistein also blocks the effect of IL-1beta, indicating involvement of tyrosine phosphorylation in the process. Treatment of JAR cells with IL-1beta activates mitogen-activated protein kinases and nuclear factor-kappaB. The nuclear factor-kappaB that is responsive to IL-1beta in these cells is the p65 homodimer. Northern blot analysis and reverse transcription-polymerase chain reaction revealed that JAR cells and human placenta express type I and type II IL-1 receptors. The binding sites for (125)I-IL-1beta are localized predominantly in the maternal-facing brush border membrane of the syncytiotrophoblast. These results show that IL-1 in the maternal circulation is likely to play a critical role in the regulation of the serotonin transporter gene expression in the placenta.

Bedside insertion of inferior vena cava filters in the intensive care unit

BACKGROUND

Injured patients are at significant risk for venous thromboembolic complications. Multiple studies have reported a benefit of prophylactic inferior vena cava filter (IVCF) insertion in selected high-risk trauma patients. Often, these high-risk patients reside in the intensive care unit (ICU) and require mechanical ventilation, intracranial pressure monitoring, multiple intravenous infusions, and other invasive monitoring modalities. This puts these patients at risk for transport from the ICU.

METHODS

We prospectively studied a series of consecutive patients undergoing bedside preinsertion contrast cavagram and IVCF insertion in the ICU.

RESULTS

Thirty-two patients received IVCF. There were no failures to insert IVCF. One insertion-site hematoma occurred; however, there were no documented insertion-site deep venous thromboses. One patient death was unrelated to the IVCF, and one potential contrast-related acute renal failure occurred in an unstable patient who underwent IVCF insertion for a pulmonary embolus.

CONCLUSION

Bedside IVCF insertion with a preinsertion cavagram is a percutaneous procedure that can be safely performed in the ICU. Bedside insertion of IVCF avoids the potential complications of transporting critically ill patients and may reduce costs.

Relating speech and swallow function to dropout in a longitudinal study of head and neck cancer

The relation between functional outcome and dropout from a 12-month follow-up period was examined in a longitudinal study whose objective was to define and quantify the functional effects of oral surgical resection and reconstruction on speech and swallowing in patients with head and neck cancer. In a group of 150 patients recruited to a surgical study in the Cancer Control Science Program in Head and Neck Cancer Rehabilitation, dropout from all causes and dropout from specific causes (medical, patient, and administrative specific) were assessed in relation to longitudinal speech and swallow function. In univariate analysis, better speech articulation was associated with decreased risk of dropout from all causes and from medical-specific causes. Better swallow performance was associated with decreased risk of medical-specific dropout. Multivariate analysis revealed the following: (1) only articulation function was associated with dropout from all causes; (2) the association of speech articulation function with medical dropout was diminished after adjusting for advanced age and surgical resection variables; (3) the association of speech articulation function became significant for patient-specific dropout after adjusting for advanced age and surgical resection variables and indicated that better function decreased the risk of this type of dropout; and (4) swallowing function was not related to dropout. Patients treated for oral or oropharyngeal cancer who have poorer speech outcomes are more likely to drop out from a longitudinal study. Basing study results on only patients who complete a longitudinal study will understate the level of dysfunction experienced.

IGF binding protein-1 (IGFBP-1) is preferentially associated with the fetal-facing basal surface of the syncytiotrophoblast in the human placenta

IGF receptors are expressed in a spatially polarized manner on the syncytiotrophoblast cell membrane. We therefore examined the hypothesis that IGFBPs expressed at the maternal-fetal interface interact with distinct surfaces of the syncytiotrophoblast membrane to modulate IGF function. Membrane vesicles were prepared specifically from the maternal-facing, microvillous membrane (MVM) and the fetal-facing, basal membrane (BM) surfaces of the syncytiotrophoblast. The association of IGFBPs with each membrane preparation was determined by ligand blot analysis. A doublet migrating at 38/42 kD was detected in both MVM and BM preparations. Selective immunoprecipitation followed by ligand blot analysis identified this IGF binding species as IGFBP-3. Additionally, a protein migrating at approximately 29 kD was associated primarily with the BM. This protein was identified as IGFBP-1 by both immunoprecipitation and ligandblotting techniques. Non-denaturing PAGE revealed five distinct bands corresponding to different degrees of phosphorylation. The phosphorylation pattern of BM-associated IGFBP-1 was identical to that of native IGFBP-1 in amniotic fluid. Immunohistological analysis of term placenta revealed IGFBP-1-specific staining of the syncytiotrophoblast and the fetal capillary/pericapillary bed. The localization of IGFBP-1 to a distinct compartment within the fetal placenta, not in proximity to the syncytiotrophoblast type I IGF receptor, suggests it may play a role in regulating/targeting IGF activity within the stromal compartment or by exerting IGF-independent effects on the basal surface of the syncytiotrophoblast. The nature of its binding to the BM has not been determined.

Identification of three cationic amino acid transporters in placental trophoblast: cloning, expression, and characterization of hCAT-1

The concentrative transfer of amino acids from maternal to fetal blood is essential to fetal growth and metabolism. Cationic amino acids are transported across the placental microvillous and basal membranes by multiple pathways which act to mediate maternal/fetal transport. To identify the cationic amino acid transporters of human placenta, total RNA was harvested from cultured trophoblast and from the BeWo choriocarcinoma cell line, b30 clone, and used for reverse transcription (RT) and polymerase chain reaction (PCR). Primers based on published sequences identified expression of mRNAs for hCATs-1, -2B, and -4. RT-PCR yielded a 2.1 kb hCAT-1 cDNA which was cloned. hCAT-1 cRNA injection into Xenopus laevis oocytes stimulated saturable lysine uptake (K(m) approximately 100 microM). In the presence of Na(+), uptake was inhibited by leucine, homoserine, and alanine but not by valine and glutamate. These transport characteristics are comparable to those of system y(+) in placental basal membrane, but differ from those of the same system in microvillous membrane. The identification, cloning, and characterization of multiple human placental cationic amino acid transporters has the potential to facilitate molecular investigation of transport by the maternal- and fetal-facing membranes of placental trophoblast and increase understanding of the mechanism of transplacental amino acid transfer.