Drug reaction with eosinophilia and systemic symptoms (DRESS): an original multisystem adverse drug reaction. Results from the prospective RegiSCAR study

BACKGROUND

Cases of severe drug hypersensitivity, demonstrating a variable spectrum of cutaneous and systemic involvement, are reported under various names, especially drug reaction with eosinophilia and systemic symptoms (DRESS). Case definition and overlap with other severe cutaneous adverse reactions (SCAR) are debated.

OBJECTIVES

To analyse the spectrum of signs and symptoms of DRESS and distribution of causative drugs in a large multicentre series.

PATIENTS AND METHODS

RegiSCAR, a multinational registry of SCAR, prospectively enrolled 201 potential cases from 2003 to mid-2009. Using a standardized scoring system, 117 cases were validated as showing probable or definite DRESS.

RESULTS

The male/female ratio was 0.80; females were borderline significantly younger than males. Next to the ubiquitous exanthema, the main features were eosinophilia (95%), visceral involvement (91%), high fever (90%), atypical lymphocytes (67%), mild mucosal involvement (56%) and lymphadenopathy (54%). The reaction was protracted in all but two patients; two patients died during the acute phase. Drug causality was plausible in 88% of cases. Antiepileptic drugs were involved in 35%, allopurinol in 18%, antimicrobial sulfonamides and dapsone in 12% and other antibiotics in 11%. The median time interval after drug intake was 22 days (interquartile range 17-31) for all drugs with (very) probable causality, with differences between drugs.

CONCLUSION

This prospective observational study supports the hypothesis that DRESS is an original phenotype among SCAR in terms of clinical and biological characteristics, causative drugs, and time relation. The diversity of causative drugs was rather limited, and mortality was lower than that suggested by prior publications.

Toxicity of melamine: the public health concern

Melamine contamination in food has resulted in sickness and deaths of human infants, pets, and farm animals in the past decade. The majority of the victims suffered from acute kidney injury, nephrolithiasis, and urolithiasis. Since then, animal studies have revealed the possible target organs of the melamine toxicity and the extent of the adverse effects of the contaminant. State-of-the-art analytical methods have been developed to achieve the "zero tolerance" aim for such economically motivated adulteration. These studies provide in-depth understanding of the melamine toxicity and promising analytical methods, which can help us safeguard our dairy food source.

Enhancement of anaerobic biohydrogen/methane production from cellulose using heat-treated activated sludge

Anaerobic digestion is an effective technology to convert cellulosic wastes to methane and hydrogen. Heat-treatment is a well known method to inhibit hydrogen-consuming bacteria in using anaerobic mixed cultures for seeding. This study aims to investigate the effects of heat-treatment temperature and time on activated sludge for fermentative hydrogen production from alpha-cellulose by response surface methodology. Hydrogen and methane production was evaluated based on the production rate and yield (the ability of converting cellulose into hydrogen and methane) with heat-treated sludge as the seed at various temperatures (60-97 degrees C) and times (20-60 min). Batch experiments were conducted at 55 degrees C and initial pH of 8.0. The results indicate that hydrogen and methane production yields peaked at 4.3 mmol H2/g cellulose and 11.6 mmol CH4/g cellulose using the seed activated sludge that was thermally treated at 60 degrees C for 40 min. These parameter values are higher than those of no-treatment seed (HY 3.6 mmol H2/g cellulose and MY 10.4 mmol CH4/g cellulose). The maximum hydrogen production rate of 26.0 mmol H2/L/d and methane production rate of 23.2 mmol CH4/L/d were obtained for the seed activated sludge that was thermally treated at 70 degrees C for 50 min and 60 degrees C for 40 min, respectively.

Effects of different inspired oxygen fractions on lipid peroxidation during general anaesthesia for elective Caesarean section

BACKGROUND

During general anaesthesia (GA) for Caesarean section (CS), fetal oxygenation is increased by administering an inspired oxygen fraction (Fi(o(2))) of 1.0. However, it is unclear whether such high Fi(o(2)) will increase oxygen free radical activity.

METHODS

We randomized 39 ASA I-II parturients undergoing elective CS under GA to receive 30% (Gp 30), 50% (Gp 50), or 100% (Gp 100) oxygen with nitrous oxide and sevoflurane adjusted to provide equivalent minimum alveolar concentration. Baseline maternal arterial blood before preoxygenation and maternal arterial, umbilical arterial and venous blood at delivery were sampled for assays of the by-product of lipid peroxidation, isoprostane, and for measurement of blood gases and oxygen content.

RESULTS

Maternal and umbilical isoprostane concentrations were similar among the three groups at delivery, despite significantly increased maternal and fetal oxygenation in Gp 100. However, paired comparisons of maternal delivery vs baseline concentration of isoprostane showed an increase at delivery for all groups [Gp 30: mean 342 (sd 210) vs 154 (65) pg ml(-1), P=0.016; Gp 50: 284 (129) vs 156 (79) pg ml(-1), P=0.009; Gp 100: 332 (126) vs 158 (68) pg ml(-1), P<0.001]. The magnitude of increase was similar in all three groups and independent of the Fi(o(2)) or duration after induction.

CONCLUSIONS

GA for CS is associated with a marked increase in free radical activity in the mother and baby. The mechanism is unclear but it is independent of the inspired oxygen in the anaesthetic mixture. Therefore, when 100% oxygen is administered with sevoflurane for GA, fetal oxygenation can be increased, without inducing an increase in lipid peroxidation.

Identification of hemopexin in tear film

Human tear fluid is a complex mixture of aqueous lipids, proteins, enzymes, and other biochemical and cellular elements. By conventional comparative proteomic approaches, we investigated the proteome in human tear fluid and compared the tear protein profile of normal control subjects with that of patients suffering from the ocular inflammatory disease vernal keratoconjunctivitis (VKC). Collected tear samples were directed to two-dimensional polyacrylamide gel electrophoresis protein separation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry peptide identification. Six differentially expressed proteins-interleukin 4, phospholipase A2, albumin, lactoferrin, hemopexin, and lipocalin-were displayed. Hemopexin had not been reported previously in tear film. Enzyme-linked immunosorbent assay confirmed that hemopexin concentrations were significantly higher in VKC tear samples and increased with disease stages. The results implied clinical interest of hemopexin in the tear proteome and eye diseases.

Anti-angiogenic effects of green tea catechin on an experimental endometriosis mouse model

BACKGROUND

The development of new blood vessels plays an essential role in growth and survival of endometriosis. Epigallocatechin gallate (EGCG) from green tea has powerful anti-angiogenic properties and our aim was to evaluate these properties in experimental endometriosis.

METHODS AND RESULTS

Eutopic endometrium from endometriosis patients was transplanted s.c. to severely compromised immunodeficient mice, randomly treated i.p. with EGCG (anti-angiogenic and -oxidant), Vitamin E (a non-angiogenic antioxidant) or saline for 2 weeks. The endometrial implant, including adjacent host outer skin and subcutaneous layers plus inner abdominal muscle and peritoneum, was collected. New microvessels were determined by species-specific immunohistochemistry. Angiogenic factors in lesions and abdominal muscle were detected by quantitative real-time PCR. Apoptosis was studied by terminal deoxynucleotidyltransferase-mediated dUTP nick-end labelling and quantitative real-time PCR. In saline control, endometrial implants developed new blood vessels with proliferating glandular epithelium and were tightly adhered to host subcutaneous and abdominal muscle layers. After EGCG, endometriotic lesions were smaller than control (P < 0.05), and glandular epithelium was smaller and eccentrically distributed. Angiogenesis in lesions from the implant and adjacent tissues was under-developed, and microvessel size and density were lower (both P < 0.01) than control. mRNA for angiogenic vascular endothelial growth factor A, but not hypoxia inducible factor 1, alpha subunit, was significantly down-regulated in lesions after EGCG (P < 0.05). In addition, apoptosis in the lesions was more obvious, and nuclear factor kappa B and mitogen activated protein kinase 1 mRNA levels were up-regulated (P < 0.05) after EGCG treatment. No differences were observed with Vitamin E treatment.

CONCLUSIONS

EGCG significantly inhibits the development of experimental endometriosis through anti-angiogenic effects.

Higher Bcl-2 levels decrease staphylococcal superantigen-induced apoptosis of CD4+ T cells in atopic dermatitis

BACKGROUND

Staphylococcal superantigens (SsAgs) contribute to the persistence of allergic skin inflammation in atopic dermatitis (AD). The aims of this study were to (1) determine whether there are differences between AD patients and healthy subjects in SsAg-induced caspase-3 activation and SsAg-induced changes of anti-apoptotic protein Bcl-2 and Bcl-2 mRNA levels of CD4+ T cells; (2) investigate the effect of interleukin (IL)-4 on SsAg-induced caspase-3 activation and SsAg-induced changes of Bcl-2 and Bcl-2 mRNA levels of CD4+ T cells.

METHODS

Using immunofluorescence staining followed by flow cytometric analysis and real-time PCR, we analyzed peripheral blood mononuclear cells with or without staphylococcal enterotoxin B (SEB) stimulation in the presence or absence of recombinant IL-4 or anti-IL-4 neutralizing antibodies in 16 AD patients and 14 healthy subjects.

RESULTS

SEB-reactive (TCRVbeta3+, Vbeta12+, and Vbeta17+) CD4+ T cells from AD patients were more resistant to SEB-induced caspase-3 activation and SEB-induced decrease of Bcl-2 and Bcl-2 mRNA than those from healthy subjects. Exogenously added IL-4 inhibited SEB-induced caspase-3 activation and SEB-induced decrease of Bcl-2 and Bcl-2 mRNA in SEB-reactive CD4+ T cells from healthy subjects. Inhibition of endogenous IL-4 by using anti-IL-4 neutralizing antibodies up-regulated SEB-induced caspase-3 activation and SEB-induced decrease of Bcl-2 and Bcl-2 mRNA in SEB-reactive CD4+ T cells from AD patients.

CONCLUSIONS

Following SsAg stimulation, IL-4 produced by T cells in AD patients down-regulates SsAg-induced caspase-3 activation and apoptosis of CD4+ T cells through inhibiting the decrease of Bcl-2. This may impair deletion of SsAg-activated T cells and resolution of allergic skin inflammation.

Uptake and distribution of catechins in fetal organs following in utero exposure in rats

BACKGROUND

Although catechins are known to be powerful antioxidants, no reports have shown their transport to fetal organs. We investigated the distribution of catechins in fetal rat organs after maternal exposure to green tea extract (GTE).

METHODS

GTE (550 mg/kg) or water was fed orally to pregnant dams at 15.5 days of gestation, the dams were sacrificed and fetal organs were dissected 0, 0.5, 1, 2, 3, 5, and 8 h later. Catechins and catechin gallates were determined by high-performance liquid chromatography (HPLC) after solid-phase extraction.

RESULTS

In the GTE-treated group, catechins were detected in most of the fetal organs studied, including the brain, eyes, heart, lungs, kidneys and liver but not in the control group. The first peak times (T(max)) were about 0.5-1 h. The maximum concentrations (C(max)) of catechins in the fetal eye were about 2-10 times higher than in the other organs, ranging from 249 pmol/g for epicatechin (EC) to 831 pmol/g for epigallocatechin gallate (EGCG). Catechin gallates were generally more readily taken up by fetal organs than catechins. EGCG had the highest level of uptake according to area under the curve (AUC) plots and the highest C(max) in all organs.

CONCLUSIONS

Various fetal organs had low but significant levels of catechins after GTE intake by the dams, and organ levels were found to be related to catechin structure. EGCG could be a potential candidate for antioxidant supplementation of the fetus in utero.

Oxidative stress in midpregnancy as a predictor of gestational hypertension and pre-eclampsia

OBJECTIVES

To explore the relationship between the levels of maternal oxidative stress and glycaemia during pregnancy and to compare the predictive values of 8-epimer of prostaglandin F(2alpha) (8-isoPGF(2alpha)) and mean arterial pressure (MAP) in midpregnancy for the development of hypertensive complications in later pregnancy.

DESIGN

Prospective observational study as an ancillary study to the Hyperglycaemia and Adverse Pregnancy Outcome (HAPO) study.

SETTING

Obstetric clinics and wards of a university teaching hospital in Hong Kong.

POPULATION

Selected women with singleton pregnancies attending the antenatal clinic.

METHODS

Pregnant women who met HAPO inclusion criteria were recruited for the study. Glucose tolerance was assessed by a 75-g 2-hour oral glucose tolerance test (OGTT) at 24-32 weeks of gestation. Fasting plasma samples for 8-isoPGF(2alpha) estimation and urine samples for 8-isoPGF(2alpha) and 2,3-dinor 8-isoPGF(2alpha) assays were collected and blood pressures measured during the OGTT visit. Random plasma and urine samples were also obtained at 34-37 weeks. Glucose results were unblinded to the attending obstetrician if limits preset under the HAPO protocol were met.

MAIN OUTCOME MEASURES

Maternal plasma 8-isoPGF(2alpha) and urinary 8-isoPGF(2alpha) and 2,3-dinor 8-isoPGF(2alpha) both at the time of OGTT (24-32 weeks) and at 34-37 weeks of gestation. Incidence of pre-eclampsia and gestational hypertension.

RESULTS

Of the 408 women who attended for OGTT at 24-32 weeks, two met the glucose criteria for unblinding and 25 had missing 8-isoPGF(2alpha) values and thus were excluded from analysis. Of the 381 women, 338 (88.7%) attended for random plasma samples at 34-37 weeks. Significant correlations were observed between maternal fasting plasma isoprostane and both fasting (r= 0.20; P < 0.001) and 2-hour (r= 0.39; P < 0.001) plasma glucose levels at the time of OGTT. Gestational hypertension/pre-eclampsia occurred in 17 (4.2%) women, and at the time of OGTT, they had significantly higher fasting plasma 8-isoPGF(2alpha) (P < 0.001), urine 8-isoPGF(2alpha) (P < 0.005) and urine 2,3-dinor 8-isoPGF(2alpha) to creatinine ratios (P < 0.001), as well as higher MAP (P < 0.001) than women who remained normotensive. At 34-37 weeks, only random plasma 8-isoPGF(2alpha) was significantly higher (P < 0.001) among the women with gestational hypertension/pre-eclampsia.

CONCLUSIONS

Plasma markers of oxidative stress were positively correlated with plasma glucose at the time of OGTT (24-32 weeks). Women who subsequently developed gestational hypertension/pre-eclampsia had significantly higher plasma and urine markers of oxidative stress at the time of OGTT but only higher plasma markers at 34-37 weeks. Plasma 8-isoPGF(2alpha) appears to be a very good predictor of subsequent gestational hypertension/pre-eclampsia when measured at the time of OGTT, but its ability to discriminate deteriorates as pregnancy advances.

The phosphotidyl inositol 3-kinase/Akt signal pathway is involved in interleukin-6-mediated Mcl-1 upregulation and anti-apoptosis activity in basal cell carcinoma cells

Dysregulation of interleukin-6 has been reported to be associated with various types of tumors, and interleukin-6 plays an important part in regulating apoptosis in many types of cells. Previously, Mcl-1 was shown to be significantly increased in interleukin-6-overexpressed basal cell carcinoma cells and conferred on them anti-apoptotic activity. The aim of this study was to investigate which signaling pathway is involved in the anti-apoptotic effect of interleukin-6 on basal cell carcinoma cells. Here we show that the addition of recombinant 100 ng per ml interleukin-6 to basal cell carcinoma cells induced a 2.3-fold increase in the level of Mcl-1 protein in basal cell carcinoma cells. Transfection with dominant-negative STAT3 (STAT3F) into inter-leukin-6-treated basal cell carcinoma cells caused a decrease of phosphotyrosyl STAT3 but did not alter Mcl-1 protein levels; however, AG490, a Janus tyrosine kinase inhibitor, was capable of inhibiting the interleukin-6-induced elevation of Mcl-1 protein. Next, interleukin-6 stimulation elicited extracellular signal-regulated kinase activation in basal cell carcinoma cells, and the mitogen-activated protein kinase inhibitor, PD98059, could affect this response without affecting the interleukin-6-medi-ated Mcl-1 upregulation. Use of the two phosphotidyl inositol 3-kinase inhibitors, LY294002 and wortmannin, to check whether this pathway is involved in Mcl-1 upregulation by interleukin-6, we found that the phosphotidyl inositol 3-kinase inhibitors completely attenuated the interleukin-6-induced Mcl-1 upregulation. Furthermore, in the interleukin-6-overexpressing basal cell carcinoma cell clone, dominant-negative Akt also significantly reduced the increased level of Mcl-1. Interestingly, Janus tyrosine kinase inhibitor, AG490, treatment strongly blocked the phosphotidyl inositol 3-kinase pathway activation, as evidenced by the decrease in phospho-Akt level. Blockage of phosphotidyl inositol 3-kinase/Akt pathway abolished the interleukin-6-mediated anti-apoptotic activity in ultraviolet B treated cells. Unexpectedly, without ultraviolet B irradiation, STAT3F transfection also induced a significant apoptosis in basal cell carcinoma/interleukin-6 cells. Taken together, our data suggest that both the phosphotidyl inositol 3-kinase/Akt and STAT3 pathways are potentially involved in interleukin-6-mediated cell survival activity in basal cell carcinoma cells; however, the upregulation of the anti-apoptotic Mcl-1 protein by interleukin-6 is mainly through the Janus tyrosine kinase/phosphotidyl inositol 3-kinase/Akt, but not the STAT3 pathway.

Genetic variation of the nucleocapsid genes of waterfowl parvovirus

Duck parvovirus (DPV) and Goose parvovirus (GPV) isolated from infected waterfowls with Derzsy's disease in the year 1999 were identified by polymerase chain reaction and sequencing. The nucleotide sequences of their viral capsid proteins (VPs) show that they share 77% similarity at the DNA, and 84.6% at the protein level. The most variable region between DPV and GPV resides in the N-terminal of VP2 before the initiation codon of VP3 with 35% (19/54) amino acids divergence. Viral capsid protein sequences diverge 4.1 to 4.4% among 1990-99 isolated strains. Variant amino acids cluster in the common regions of VP3 at residues 203-266 and 482-534 which overlaps with the regions proposed to expose on the outer surfaces of parvoviral particles, implying that selective pressure from host immune system might play a part. These data provide useful information for antigenic epitope prediction. This study also reveal the presence of conserved strain-specific residues in VPs and these residues seldom vary among different viral isolates, suggesting that they might be functionally important and worth further investigation.

Gemcitabine-induced acute lipodermatosclerosis-like reaction

Gemcitabine is considered to be a well-tolerated and safe cytostatic drug because of the relative lack of side effects. Cutaneous reactions due to gemcitabine treatment, including alopecia and maculopapular eruption, are well known. We report one patient with squamous cell carcinoma of the lung who developed a gemcitabine-induced cutaneous reaction mimicking acute lipodermatosclerosis. This case has never been reported in the literature before.

Overexpression, biophysical characterization, and crystallization of ribonuclease I from Escherichia coli, a broad-specificity enzyme in the RNase T2 family

We have constructed a strain that overproduces ribonuclease I of Escherichia coli and we have purified large quantities of the enzyme. Data from fluorescence, CD, and DSC measurements showed that it was a very stable protein. The conformation energy determined from urea and guanidine hydrochloride denaturation experiments was 11.5 kcal mol(-1) at pH 7.5. Thermal denaturation studies indicated that it had a T(m) of 64 degrees C at pH 4.0. RNase I belongs to the RNase T2/S-RNase group of endoribonucleases, but near the amino terminus it has an unusually long hydrophilic segment. Part of this was removed in the deletion construct, RNase I Delta(26-38). We have obtained crystals of both RNase I and of an enzyme-G2'p5'G complex in the P2(1) space group and oligonucleotide complexes with both wild type and mutant enzymes. The current study lays the groundwork for extensive investigation into the structure, function, and physical properties of this widely distributed group of ribonucleases.

Vaccination with the glycoprotein D gene of pseudorabies virus delivered by nonpathogenic Escherichia coli elicits protective immune responses

Attenuated intracellular bacteria, such as Salmonella and Shigella, have been exploited to act as gene delivery vectors. In this study, we report that nonpathogenic, live Escherichia coli can be used for the delivery of DNA vaccines in vivo, leading to generation of immune responses against plasmid-encoded foreign antigens. The pseudorabies virus (PrV) DNA vaccine carrying the glycoprotein D (gD) gene delivered by E. coli was able to induce protective immune responses in mice against a lethal PrV challenge. Co-delivery of E. coli carrying plasmid DNA encoding prothymosin alpha enhanced cellular immune responses to the PrV DNA vaccine delivered by E. coli. Our results suggest that nonpathogenic E. coli may be used as a vector for DNA vaccines in veterinary uses.

Induction of apoptosis by esculetin in human leukemia cells

Esculetin, a coumarin compound, has been shown to exhibit antioxidant and anti-inflammatory effects. In the present study, esculetin was found to inhibit the survival of human promyelocytic leukemia HL-60 cells in a concentration-dependent and time-dependent manner. HL-60 cells underwent internucleosomal DNA fragmentation and morphological changes characteristic of apoptosis after a 24-h treatment with esculetin (100 microM). Flow cytometric analysis showed that the hypodiploid nuclei of HL-60 cells were increased to 40.93% after a 36-h treatment with esculetin (100 microM). Further investigation showed that esculetin induced the release of cytochrome c from mitochondria into cytosol in a time-dependent and concentration-dependent manner. Moreover, esculetin application reduced Bcl-2 protein expression to 58% after 9 h as compared with that time at 0. Cysteine protease 32 kDa proenzyme (CPP32), a caspase 3, was activated and its substrate, poly (adenosine diphosphate-ribose) polymerase, was cleaved after a 24-h treatment of HL-60 cells with esculetin. These data suggest that esculetin induces apoptosis in human leukemia cells by increasing cytosolic translocation of cytochrome c and activation of CPP32.

Sulfation and attrition of calcium sorbent in a bubbling fluidized bed

A bubbling fluidized bed reactor was used as a desulfurization apparatus in this study. The height of the bed was 2.5m, and the inner diameter was 9cm. The bed materials were calcium sorbent and silica sand. The effects of the operating parameters of the flue gas desulfurization including relative humidity, temperature, superficial gas velocity, and the particle size of calcium sorbent on SO2 removal efficiency and calcium sorbent conversion and attrition rate in the fluidized bed were investigated. It was found that the temperature effect in our system was negligible from 40 to 65 degrees C. A higher relative humidity had a higher calcium conversion and a higher sulfur dioxide removal efficiency. Moreover, a smaller particle size of calcium sorbent had a lower calcium conversion in the cyclone but a higher sulfur dioxide removal efficiency. A lower superficial gas velocity resulted in a higher sulfur dioxide removal efficiency and a higher calcium conversion, thus, the total volume of the flue gas treated was maximum near the minimum fluidization velocity. Finally, an attrition rate model proposed in this study could predict the elutriation rate satisfactorily.

Induction of apoptosis by hibiscus protocatechuic acid in human leukemia cells via reduction of retinoblastoma (RB) phosphorylation and Bcl-2 expression

Hibiscus protocatechuic acid (PCA), a phenolic compound isolated from the dried flower of Hibiscus sabdariffa L. (Malvaceae), demonstrated antioxidant and antitumor promotion effects in our previous study. In the present study, Hibiscus PCA was found to inhibit the survival of human promyelocytic leukemia HL-60 cells in a concentration- and time-dependent manner. The study revealed that HL-60 cells underwent internucleosomal DNA fragmentation and morphological changes characteristic of apoptosis after a 9-hr treatment with Hibiscus PCA (2 mM). Flow cytometric analysis of the DNA content of cells treated with PCA for 12 hr showed that the cells were distributed mainly in the hypodiploid phase (apoptotic peak, 46.7%), less in the G(1) (34.2%) and S phase (14.0%), and few in the G(2)/M phase (5.1%). Moreover, PCA treatment caused an increase in the level of hypophosphorylated retinoblastoma (RB; 180% of control at the 6-hr time point) and, on the contrary, a decline in hyperphosphorylated RB. A rapid loss of RB was observed when the treatment period was extended. Further studies showed that Hibiscus PCA application reduced Bcl-2 protein expression to 47%, and increased Bax protein expression to 181% after 1.5 hr as compared with time 0. Overexpression of Bcl-2 in HL-60 cells delayed the occurrence of Hibiscus PCA-induced apoptosis. These data suggest that Hibiscus PCA is an apoptosis inducer in human leukemia cells, and that RB phosphorylation and Bcl-2 protein may play a crucial role in the early stage.